1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * USB hub driver.
   4 *
   5 * (C) Copyright 1999 Linus Torvalds
   6 * (C) Copyright 1999 Johannes Erdfelt
   7 * (C) Copyright 1999 Gregory P. Smith
   8 * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   9 *
  10 * Released under the GPLv2 only.
  11 */
  12
  13#include <linux/kernel.h>
  14#include <linux/errno.h>
  15#include <linux/module.h>
  16#include <linux/moduleparam.h>
  17#include <linux/completion.h>
  18#include <linux/sched/mm.h>
  19#include <linux/list.h>
  20#include <linux/slab.h>
  21#include <linux/kcov.h>
  22#include <linux/ioctl.h>
  23#include <linux/usb.h>
  24#include <linux/usbdevice_fs.h>
  25#include <linux/usb/hcd.h>
  26#include <linux/usb/onboard_hub.h>
  27#include <linux/usb/otg.h>
  28#include <linux/usb/quirks.h>
  29#include <linux/workqueue.h>
  30#include <linux/mutex.h>
  31#include <linux/random.h>
  32#include <linux/pm_qos.h>
  33#include <linux/kobject.h>
  34
  35#include <linux/bitfield.h>
  36#include <linux/uaccess.h>
  37#include <asm/byteorder.h>
  38
  39#include "hub.h"
  40#include "phy.h"
  41#include "otg_productlist.h"
  42
  43#define USB_VENDOR_GENESYS_LOGIC		0x05e3
  44#define USB_VENDOR_SMSC				0x0424
  45#define USB_PRODUCT_USB5534B			0x5534
  46#define USB_VENDOR_CYPRESS			0x04b4
  47#define USB_PRODUCT_CY7C65632			0x6570
  48#define USB_VENDOR_TEXAS_INSTRUMENTS		0x0451
  49#define USB_PRODUCT_TUSB8041_USB3		0x8140
  50#define USB_PRODUCT_TUSB8041_USB2		0x8142
  51#define USB_VENDOR_MICROCHIP			0x0424
  52#define USB_PRODUCT_USB4913			0x4913
  53#define USB_PRODUCT_USB4914			0x4914
  54#define USB_PRODUCT_USB4915			0x4915
  55#define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND	BIT(0)
  56#define HUB_QUIRK_DISABLE_AUTOSUSPEND		BIT(1)
  57#define HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL	BIT(2)
  58
  59#define USB_TP_TRANSMISSION_DELAY	40	/* ns */
  60#define USB_TP_TRANSMISSION_DELAY_MAX	65535	/* ns */
  61#define USB_PING_RESPONSE_TIME		400	/* ns */
  62#define USB_REDUCE_FRAME_INTR_BINTERVAL	9
  63
  64/*
  65 * The SET_ADDRESS request timeout will be 500 ms when
  66 * USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT quirk flag is set.
  67 */
  68#define USB_SHORT_SET_ADDRESS_REQ_TIMEOUT	500  /* ms */
  69
  70/* Protect struct usb_device->state and ->children members
  71 * Note: Both are also protected by ->dev.sem, except that ->state can
  72 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  73static DEFINE_SPINLOCK(device_state_lock);
  74
  75/* workqueue to process hub events */
  76static struct workqueue_struct *hub_wq;
  77static void hub_event(struct work_struct *work);
  78
  79/* synchronize hub-port add/remove and peering operations */
  80DEFINE_MUTEX(usb_port_peer_mutex);
  81
  82/* cycle leds on hubs that aren't blinking for attention */
  83static bool blinkenlights;
  84module_param(blinkenlights, bool, S_IRUGO);
  85MODULE_PARM_DESC(blinkenlights, "true to cycle leds on hubs");
  86
  87/*
  88 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
  89 * 10 seconds to send reply for the initial 64-byte descriptor request.
  90 */
  91/* define initial 64-byte descriptor request timeout in milliseconds */
  92static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
  93module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
  94MODULE_PARM_DESC(initial_descriptor_timeout,
  95		"initial 64-byte descriptor request timeout in milliseconds "
  96		"(default 5000 - 5.0 seconds)");
  97
  98/*
  99 * As of 2.6.10 we introduce a new USB device initialization scheme which
 100 * closely resembles the way Windows works.  Hopefully it will be compatible
 101 * with a wider range of devices than the old scheme.  However some previously
 102 * working devices may start giving rise to "device not accepting address"
 103 * errors; if that happens the user can try the old scheme by adjusting the
 104 * following module parameters.
 105 *
 106 * For maximum flexibility there are two boolean parameters to control the
 107 * hub driver's behavior.  On the first initialization attempt, if the
 108 * "old_scheme_first" parameter is set then the old scheme will be used,
 109 * otherwise the new scheme is used.  If that fails and "use_both_schemes"
 110 * is set, then the driver will make another attempt, using the other scheme.
 111 */
 112static bool old_scheme_first;
 113module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
 114MODULE_PARM_DESC(old_scheme_first,
 115		 "start with the old device initialization scheme");
 116
 117static bool use_both_schemes = true;
 118module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
 119MODULE_PARM_DESC(use_both_schemes,
 120		"try the other device initialization scheme if the "
 121		"first one fails");
 122
 123/* Mutual exclusion for EHCI CF initialization.  This interferes with
 124 * port reset on some companion controllers.
 125 */
 126DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
 127EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
 128
 129#define HUB_DEBOUNCE_TIMEOUT	2000
 130#define HUB_DEBOUNCE_STEP	  25
 131#define HUB_DEBOUNCE_STABLE	 100
 132
 
 133static int usb_reset_and_verify_device(struct usb_device *udev);
 134static int hub_port_disable(struct usb_hub *hub, int port1, int set_state);
 135static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
 136		u16 portstatus);
 137
 138static inline char *portspeed(struct usb_hub *hub, int portstatus)
 139{
 140	if (hub_is_superspeedplus(hub->hdev))
 141		return "10.0 Gb/s";
 142	if (hub_is_superspeed(hub->hdev))
 143		return "5.0 Gb/s";
 144	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
 145		return "480 Mb/s";
 146	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
 147		return "1.5 Mb/s";
 148	else
 149		return "12 Mb/s";
 150}
 151
 152/* Note that hdev or one of its children must be locked! */
 153struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
 154{
 155	if (!hdev || !hdev->actconfig || !hdev->maxchild)
 156		return NULL;
 157	return usb_get_intfdata(hdev->actconfig->interface[0]);
 158}
 159
 160int usb_device_supports_lpm(struct usb_device *udev)
 161{
 162	/* Some devices have trouble with LPM */
 163	if (udev->quirks & USB_QUIRK_NO_LPM)
 164		return 0;
 165
 166	/* Skip if the device BOS descriptor couldn't be read */
 167	if (!udev->bos)
 168		return 0;
 169
 170	/* USB 2.1 (and greater) devices indicate LPM support through
 171	 * their USB 2.0 Extended Capabilities BOS descriptor.
 172	 */
 173	if (udev->speed == USB_SPEED_HIGH || udev->speed == USB_SPEED_FULL) {
 174		if (udev->bos->ext_cap &&
 175			(USB_LPM_SUPPORT &
 176			 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
 177			return 1;
 178		return 0;
 179	}
 180
 181	/*
 182	 * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
 183	 * However, there are some that don't, and they set the U1/U2 exit
 184	 * latencies to zero.
 185	 */
 186	if (!udev->bos->ss_cap) {
 187		dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
 188		return 0;
 189	}
 190
 191	if (udev->bos->ss_cap->bU1devExitLat == 0 &&
 192			udev->bos->ss_cap->bU2DevExitLat == 0) {
 193		if (udev->parent)
 194			dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
 195		else
 196			dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
 197		return 0;
 198	}
 199
 200	if (!udev->parent || udev->parent->lpm_capable)
 201		return 1;
 202	return 0;
 203}
 204
 205/*
 206 * Set the Maximum Exit Latency (MEL) for the host to wakup up the path from
 207 * U1/U2, send a PING to the device and receive a PING_RESPONSE.
 208 * See USB 3.1 section C.1.5.2
 209 */
 210static void usb_set_lpm_mel(struct usb_device *udev,
 211		struct usb3_lpm_parameters *udev_lpm_params,
 212		unsigned int udev_exit_latency,
 213		struct usb_hub *hub,
 214		struct usb3_lpm_parameters *hub_lpm_params,
 215		unsigned int hub_exit_latency)
 216{
 217	unsigned int total_mel;
 218
 219	/*
 220	 * tMEL1. time to transition path from host to device into U0.
 221	 * MEL for parent already contains the delay up to parent, so only add
 222	 * the exit latency for the last link (pick the slower exit latency),
 223	 * and the hub header decode latency. See USB 3.1 section C 2.2.1
 224	 * Store MEL in nanoseconds
 225	 */
 226	total_mel = hub_lpm_params->mel +
 227		max(udev_exit_latency, hub_exit_latency) * 1000 +
 228		hub->descriptor->u.ss.bHubHdrDecLat * 100;
 229
 230	/*
 231	 * tMEL2. Time to submit PING packet. Sum of tTPTransmissionDelay for
 232	 * each link + wHubDelay for each hub. Add only for last link.
 233	 * tMEL4, the time for PING_RESPONSE to traverse upstream is similar.
 234	 * Multiply by 2 to include it as well.
 235	 */
 236	total_mel += (__le16_to_cpu(hub->descriptor->u.ss.wHubDelay) +
 237		      USB_TP_TRANSMISSION_DELAY) * 2;
 238
 239	/*
 240	 * tMEL3, tPingResponse. Time taken by device to generate PING_RESPONSE
 241	 * after receiving PING. Also add 2100ns as stated in USB 3.1 C 1.5.2.4
 242	 * to cover the delay if the PING_RESPONSE is queued behind a Max Packet
 243	 * Size DP.
 244	 * Note these delays should be added only once for the entire path, so
 245	 * add them to the MEL of the device connected to the roothub.
 246	 */
 247	if (!hub->hdev->parent)
 248		total_mel += USB_PING_RESPONSE_TIME + 2100;
 249
 250	udev_lpm_params->mel = total_mel;
 251}
 252
 253/*
 254 * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
 255 * a transition from either U1 or U2.
 256 */
 257static void usb_set_lpm_pel(struct usb_device *udev,
 258		struct usb3_lpm_parameters *udev_lpm_params,
 259		unsigned int udev_exit_latency,
 260		struct usb_hub *hub,
 261		struct usb3_lpm_parameters *hub_lpm_params,
 262		unsigned int hub_exit_latency,
 263		unsigned int port_to_port_exit_latency)
 264{
 265	unsigned int first_link_pel;
 266	unsigned int hub_pel;
 267
 268	/*
 269	 * First, the device sends an LFPS to transition the link between the
 270	 * device and the parent hub into U0.  The exit latency is the bigger of
 271	 * the device exit latency or the hub exit latency.
 272	 */
 273	if (udev_exit_latency > hub_exit_latency)
 274		first_link_pel = udev_exit_latency * 1000;
 275	else
 276		first_link_pel = hub_exit_latency * 1000;
 277
 278	/*
 279	 * When the hub starts to receive the LFPS, there is a slight delay for
 280	 * it to figure out that one of the ports is sending an LFPS.  Then it
 281	 * will forward the LFPS to its upstream link.  The exit latency is the
 282	 * delay, plus the PEL that we calculated for this hub.
 283	 */
 284	hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;
 285
 286	/*
 287	 * According to figure C-7 in the USB 3.0 spec, the PEL for this device
 288	 * is the greater of the two exit latencies.
 289	 */
 290	if (first_link_pel > hub_pel)
 291		udev_lpm_params->pel = first_link_pel;
 292	else
 293		udev_lpm_params->pel = hub_pel;
 294}
 295
 296/*
 297 * Set the System Exit Latency (SEL) to indicate the total worst-case time from
 298 * when a device initiates a transition to U0, until when it will receive the
 299 * first packet from the host controller.
 300 *
 301 * Section C.1.5.1 describes the four components to this:
 302 *  - t1: device PEL
 303 *  - t2: time for the ERDY to make it from the device to the host.
 304 *  - t3: a host-specific delay to process the ERDY.
 305 *  - t4: time for the packet to make it from the host to the device.
 306 *
 307 * t3 is specific to both the xHCI host and the platform the host is integrated
 308 * into.  The Intel HW folks have said it's negligible, FIXME if a different
 309 * vendor says otherwise.
 310 */
 311static void usb_set_lpm_sel(struct usb_device *udev,
 312		struct usb3_lpm_parameters *udev_lpm_params)
 313{
 314	struct usb_device *parent;
 315	unsigned int num_hubs;
 316	unsigned int total_sel;
 317
 318	/* t1 = device PEL */
 319	total_sel = udev_lpm_params->pel;
 320	/* How many external hubs are in between the device & the root port. */
 321	for (parent = udev->parent, num_hubs = 0; parent->parent;
 322			parent = parent->parent)
 323		num_hubs++;
 324	/* t2 = 2.1us + 250ns * (num_hubs - 1) */
 325	if (num_hubs > 0)
 326		total_sel += 2100 + 250 * (num_hubs - 1);
 327
 328	/* t4 = 250ns * num_hubs */
 329	total_sel += 250 * num_hubs;
 330
 331	udev_lpm_params->sel = total_sel;
 332}
 333
 334static void usb_set_lpm_parameters(struct usb_device *udev)
 335{
 336	struct usb_hub *hub;
 337	unsigned int port_to_port_delay;
 338	unsigned int udev_u1_del;
 339	unsigned int udev_u2_del;
 340	unsigned int hub_u1_del;
 341	unsigned int hub_u2_del;
 342
 343	if (!udev->lpm_capable || udev->speed < USB_SPEED_SUPER)
 344		return;
 345
 346	/* Skip if the device BOS descriptor couldn't be read */
 347	if (!udev->bos)
 348		return;
 349
 350	hub = usb_hub_to_struct_hub(udev->parent);
 351	/* It doesn't take time to transition the roothub into U0, since it
 352	 * doesn't have an upstream link.
 353	 */
 354	if (!hub)
 355		return;
 356
 357	udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
 358	udev_u2_del = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat);
 359	hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
 360	hub_u2_del = le16_to_cpu(udev->parent->bos->ss_cap->bU2DevExitLat);
 361
 362	usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
 363			hub, &udev->parent->u1_params, hub_u1_del);
 364
 365	usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
 366			hub, &udev->parent->u2_params, hub_u2_del);
 367
 368	/*
 369	 * Appendix C, section C.2.2.2, says that there is a slight delay from
 370	 * when the parent hub notices the downstream port is trying to
 371	 * transition to U0 to when the hub initiates a U0 transition on its
 372	 * upstream port.  The section says the delays are tPort2PortU1EL and
 373	 * tPort2PortU2EL, but it doesn't define what they are.
 374	 *
 375	 * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
 376	 * about the same delays.  Use the maximum delay calculations from those
 377	 * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
 378	 * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
 379	 * assume the device exit latencies they are talking about are the hub
 380	 * exit latencies.
 381	 *
 382	 * What do we do if the U2 exit latency is less than the U1 exit
 383	 * latency?  It's possible, although not likely...
 384	 */
 385	port_to_port_delay = 1;
 386
 387	usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
 388			hub, &udev->parent->u1_params, hub_u1_del,
 389			port_to_port_delay);
 390
 391	if (hub_u2_del > hub_u1_del)
 392		port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
 393	else
 394		port_to_port_delay = 1 + hub_u1_del;
 395
 396	usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
 397			hub, &udev->parent->u2_params, hub_u2_del,
 398			port_to_port_delay);
 399
 400	/* Now that we've got PEL, calculate SEL. */
 401	usb_set_lpm_sel(udev, &udev->u1_params);
 402	usb_set_lpm_sel(udev, &udev->u2_params);
 403}
 404
 405/* USB 2.0 spec Section 11.24.4.5 */
 406static int get_hub_descriptor(struct usb_device *hdev,
 407		struct usb_hub_descriptor *desc)
 408{
 409	int i, ret, size;
 410	unsigned dtype;
 411
 412	if (hub_is_superspeed(hdev)) {
 413		dtype = USB_DT_SS_HUB;
 414		size = USB_DT_SS_HUB_SIZE;
 415	} else {
 416		dtype = USB_DT_HUB;
 417		size = sizeof(struct usb_hub_descriptor);
 418	}
 419
 420	for (i = 0; i < 3; i++) {
 421		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 422			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 423			dtype << 8, 0, desc, size,
 424			USB_CTRL_GET_TIMEOUT);
 425		if (hub_is_superspeed(hdev)) {
 426			if (ret == size)
 427				return ret;
 428		} else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {
 429			/* Make sure we have the DeviceRemovable field. */
 430			size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;
 431			if (ret < size)
 432				return -EMSGSIZE;
 433			return ret;
 434		}
 435	}
 436	return -EINVAL;
 437}
 438
 439/*
 440 * USB 2.0 spec Section 11.24.2.1
 441 */
 442static int clear_hub_feature(struct usb_device *hdev, int feature)
 443{
 444	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 445		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 446}
 447
 448/*
 449 * USB 2.0 spec Section 11.24.2.2
 450 */
 451int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
 452{
 453	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 454		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 455		NULL, 0, 1000);
 456}
 457
 458/*
 459 * USB 2.0 spec Section 11.24.2.13
 460 */
 461static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 462{
 463	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 464		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 465		NULL, 0, 1000);
 466}
 467
 468static char *to_led_name(int selector)
 469{
 470	switch (selector) {
 471	case HUB_LED_AMBER:
 472		return "amber";
 473	case HUB_LED_GREEN:
 474		return "green";
 475	case HUB_LED_OFF:
 476		return "off";
 477	case HUB_LED_AUTO:
 478		return "auto";
 479	default:
 480		return "??";
 481	}
 482}
 483
 484/*
 485 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 486 * for info about using port indicators
 487 */
 488static void set_port_led(struct usb_hub *hub, int port1, int selector)
 489{
 490	struct usb_port *port_dev = hub->ports[port1 - 1];
 491	int status;
 492
 493	status = set_port_feature(hub->hdev, (selector << 8) | port1,
 494			USB_PORT_FEAT_INDICATOR);
 495	dev_dbg(&port_dev->dev, "indicator %s status %d\n",
 496		to_led_name(selector), status);
 497}
 498
 499#define	LED_CYCLE_PERIOD	((2*HZ)/3)
 500
 501static void led_work(struct work_struct *work)
 502{
 503	struct usb_hub		*hub =
 504		container_of(work, struct usb_hub, leds.work);
 505	struct usb_device	*hdev = hub->hdev;
 506	unsigned		i;
 507	unsigned		changed = 0;
 508	int			cursor = -1;
 509
 510	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 511		return;
 512
 513	for (i = 0; i < hdev->maxchild; i++) {
 514		unsigned	selector, mode;
 515
 516		/* 30%-50% duty cycle */
 517
 518		switch (hub->indicator[i]) {
 519		/* cycle marker */
 520		case INDICATOR_CYCLE:
 521			cursor = i;
 522			selector = HUB_LED_AUTO;
 523			mode = INDICATOR_AUTO;
 524			break;
 525		/* blinking green = sw attention */
 526		case INDICATOR_GREEN_BLINK:
 527			selector = HUB_LED_GREEN;
 528			mode = INDICATOR_GREEN_BLINK_OFF;
 529			break;
 530		case INDICATOR_GREEN_BLINK_OFF:
 531			selector = HUB_LED_OFF;
 532			mode = INDICATOR_GREEN_BLINK;
 533			break;
 534		/* blinking amber = hw attention */
 535		case INDICATOR_AMBER_BLINK:
 536			selector = HUB_LED_AMBER;
 537			mode = INDICATOR_AMBER_BLINK_OFF;
 538			break;
 539		case INDICATOR_AMBER_BLINK_OFF:
 540			selector = HUB_LED_OFF;
 541			mode = INDICATOR_AMBER_BLINK;
 542			break;
 543		/* blink green/amber = reserved */
 544		case INDICATOR_ALT_BLINK:
 545			selector = HUB_LED_GREEN;
 546			mode = INDICATOR_ALT_BLINK_OFF;
 547			break;
 548		case INDICATOR_ALT_BLINK_OFF:
 549			selector = HUB_LED_AMBER;
 550			mode = INDICATOR_ALT_BLINK;
 551			break;
 552		default:
 553			continue;
 554		}
 555		if (selector != HUB_LED_AUTO)
 556			changed = 1;
 557		set_port_led(hub, i + 1, selector);
 558		hub->indicator[i] = mode;
 559	}
 560	if (!changed && blinkenlights) {
 561		cursor++;
 562		cursor %= hdev->maxchild;
 563		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 564		hub->indicator[cursor] = INDICATOR_CYCLE;
 565		changed++;
 566	}
 567	if (changed)
 568		queue_delayed_work(system_power_efficient_wq,
 569				&hub->leds, LED_CYCLE_PERIOD);
 570}
 571
 572/* use a short timeout for hub/port status fetches */
 573#define	USB_STS_TIMEOUT		1000
 574#define	USB_STS_RETRIES		5
 575
 576/*
 577 * USB 2.0 spec Section 11.24.2.6
 578 */
 579static int get_hub_status(struct usb_device *hdev,
 580		struct usb_hub_status *data)
 581{
 582	int i, status = -ETIMEDOUT;
 583
 584	for (i = 0; i < USB_STS_RETRIES &&
 585			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 586		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 587			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 588			data, sizeof(*data), USB_STS_TIMEOUT);
 589	}
 590	return status;
 591}
 592
 593/*
 594 * USB 2.0 spec Section 11.24.2.7
 595 * USB 3.1 takes into use the wValue and wLength fields, spec Section 10.16.2.6
 596 */
 597static int get_port_status(struct usb_device *hdev, int port1,
 598			   void *data, u16 value, u16 length)
 599{
 600	int i, status = -ETIMEDOUT;
 601
 602	for (i = 0; i < USB_STS_RETRIES &&
 603			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 604		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 605			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, value,
 606			port1, data, length, USB_STS_TIMEOUT);
 607	}
 608	return status;
 609}
 610
 611static int hub_ext_port_status(struct usb_hub *hub, int port1, int type,
 612			       u16 *status, u16 *change, u32 *ext_status)
 613{
 614	int ret;
 615	int len = 4;
 616
 617	if (type != HUB_PORT_STATUS)
 618		len = 8;
 619
 620	mutex_lock(&hub->status_mutex);
 621	ret = get_port_status(hub->hdev, port1, &hub->status->port, type, len);
 622	if (ret < len) {
 623		if (ret != -ENODEV)
 624			dev_err(hub->intfdev,
 625				"%s failed (err = %d)\n", __func__, ret);
 626		if (ret >= 0)
 627			ret = -EIO;
 628	} else {
 629		*status = le16_to_cpu(hub->status->port.wPortStatus);
 630		*change = le16_to_cpu(hub->status->port.wPortChange);
 631		if (type != HUB_PORT_STATUS && ext_status)
 632			*ext_status = le32_to_cpu(
 633				hub->status->port.dwExtPortStatus);
 634		ret = 0;
 635	}
 636	mutex_unlock(&hub->status_mutex);
 637
 638	/*
 639	 * There is no need to lock status_mutex here, because status_mutex
 640	 * protects hub->status, and the phy driver only checks the port
 641	 * status without changing the status.
 642	 */
 643	if (!ret) {
 644		struct usb_device *hdev = hub->hdev;
 645
 646		/*
 647		 * Only roothub will be notified of connection changes,
 648		 * since the USB PHY only cares about changes at the next
 649		 * level.
 650		 */
 651		if (is_root_hub(hdev)) {
 652			struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
 653			bool connect;
 654			bool connect_change;
 655
 656			connect_change = *change & USB_PORT_STAT_C_CONNECTION;
 657			connect = *status & USB_PORT_STAT_CONNECTION;
 658			if (connect_change && connect)
 659				usb_phy_roothub_notify_connect(hcd->phy_roothub, port1 - 1);
 660			else if (connect_change)
 661				usb_phy_roothub_notify_disconnect(hcd->phy_roothub, port1 - 1);
 662		}
 663	}
 664
 665	return ret;
 666}
 667
 668int usb_hub_port_status(struct usb_hub *hub, int port1,
 669		u16 *status, u16 *change)
 670{
 671	return hub_ext_port_status(hub, port1, HUB_PORT_STATUS,
 672				   status, change, NULL);
 673}
 674
 675static void hub_resubmit_irq_urb(struct usb_hub *hub)
 676{
 677	unsigned long flags;
 678	int status;
 679
 680	spin_lock_irqsave(&hub->irq_urb_lock, flags);
 681
 682	if (hub->quiescing) {
 683		spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 684		return;
 685	}
 686
 687	status = usb_submit_urb(hub->urb, GFP_ATOMIC);
 688	if (status && status != -ENODEV && status != -EPERM &&
 689	    status != -ESHUTDOWN) {
 690		dev_err(hub->intfdev, "resubmit --> %d\n", status);
 691		mod_timer(&hub->irq_urb_retry, jiffies + HZ);
 692	}
 693
 694	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 695}
 696
 697static void hub_retry_irq_urb(struct timer_list *t)
 698{
 699	struct usb_hub *hub = from_timer(hub, t, irq_urb_retry);
 700
 701	hub_resubmit_irq_urb(hub);
 702}
 703
 704
 705static void kick_hub_wq(struct usb_hub *hub)
 706{
 707	struct usb_interface *intf;
 708
 709	if (hub->disconnected || work_pending(&hub->events))
 710		return;
 711
 712	/*
 713	 * Suppress autosuspend until the event is proceed.
 714	 *
 715	 * Be careful and make sure that the symmetric operation is
 716	 * always called. We are here only when there is no pending
 717	 * work for this hub. Therefore put the interface either when
 718	 * the new work is called or when it is canceled.
 719	 */
 720	intf = to_usb_interface(hub->intfdev);
 721	usb_autopm_get_interface_no_resume(intf);
 722	hub_get(hub);
 723
 724	if (queue_work(hub_wq, &hub->events))
 725		return;
 726
 727	/* the work has already been scheduled */
 728	usb_autopm_put_interface_async(intf);
 729	hub_put(hub);
 730}
 731
 732void usb_kick_hub_wq(struct usb_device *hdev)
 733{
 734	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 735
 736	if (hub)
 737		kick_hub_wq(hub);
 738}
 739
 740/*
 741 * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
 742 * Notification, which indicates it had initiated remote wakeup.
 743 *
 744 * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
 745 * device initiates resume, so the USB core will not receive notice of the
 746 * resume through the normal hub interrupt URB.
 747 */
 748void usb_wakeup_notification(struct usb_device *hdev,
 749		unsigned int portnum)
 750{
 751	struct usb_hub *hub;
 752	struct usb_port *port_dev;
 753
 754	if (!hdev)
 755		return;
 756
 757	hub = usb_hub_to_struct_hub(hdev);
 758	if (hub) {
 759		port_dev = hub->ports[portnum - 1];
 760		if (port_dev && port_dev->child)
 761			pm_wakeup_event(&port_dev->child->dev, 0);
 762
 763		set_bit(portnum, hub->wakeup_bits);
 764		kick_hub_wq(hub);
 765	}
 766}
 767EXPORT_SYMBOL_GPL(usb_wakeup_notification);
 768
 769/* completion function, fires on port status changes and various faults */
 770static void hub_irq(struct urb *urb)
 771{
 772	struct usb_hub *hub = urb->context;
 773	int status = urb->status;
 774	unsigned i;
 775	unsigned long bits;
 776
 777	switch (status) {
 778	case -ENOENT:		/* synchronous unlink */
 779	case -ECONNRESET:	/* async unlink */
 780	case -ESHUTDOWN:	/* hardware going away */
 781		return;
 782
 783	default:		/* presumably an error */
 784		/* Cause a hub reset after 10 consecutive errors */
 785		dev_dbg(hub->intfdev, "transfer --> %d\n", status);
 786		if ((++hub->nerrors < 10) || hub->error)
 787			goto resubmit;
 788		hub->error = status;
 789		fallthrough;
 790
 791	/* let hub_wq handle things */
 792	case 0:			/* we got data:  port status changed */
 793		bits = 0;
 794		for (i = 0; i < urb->actual_length; ++i)
 795			bits |= ((unsigned long) ((*hub->buffer)[i]))
 796					<< (i*8);
 797		hub->event_bits[0] = bits;
 798		break;
 799	}
 800
 801	hub->nerrors = 0;
 802
 803	/* Something happened, let hub_wq figure it out */
 804	kick_hub_wq(hub);
 805
 806resubmit:
 807	hub_resubmit_irq_urb(hub);
 808}
 809
 810/* USB 2.0 spec Section 11.24.2.3 */
 811static inline int
 812hub_clear_tt_buffer(struct usb_device *hdev, u16 devinfo, u16 tt)
 813{
 814	/* Need to clear both directions for control ep */
 815	if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
 816			USB_ENDPOINT_XFER_CONTROL) {
 817		int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 818				HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
 819				devinfo ^ 0x8000, tt, NULL, 0, 1000);
 820		if (status)
 821			return status;
 822	}
 823	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 824			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 825			       tt, NULL, 0, 1000);
 826}
 827
 828/*
 829 * enumeration blocks hub_wq for a long time. we use keventd instead, since
 830 * long blocking there is the exception, not the rule.  accordingly, HCDs
 831 * talking to TTs must queue control transfers (not just bulk and iso), so
 832 * both can talk to the same hub concurrently.
 833 */
 834static void hub_tt_work(struct work_struct *work)
 835{
 836	struct usb_hub		*hub =
 837		container_of(work, struct usb_hub, tt.clear_work);
 838	unsigned long		flags;
 839
 840	spin_lock_irqsave(&hub->tt.lock, flags);
 841	while (!list_empty(&hub->tt.clear_list)) {
 842		struct list_head	*next;
 843		struct usb_tt_clear	*clear;
 844		struct usb_device	*hdev = hub->hdev;
 845		const struct hc_driver	*drv;
 846		int			status;
 847
 848		next = hub->tt.clear_list.next;
 849		clear = list_entry(next, struct usb_tt_clear, clear_list);
 850		list_del(&clear->clear_list);
 851
 852		/* drop lock so HCD can concurrently report other TT errors */
 853		spin_unlock_irqrestore(&hub->tt.lock, flags);
 854		status = hub_clear_tt_buffer(hdev, clear->devinfo, clear->tt);
 855		if (status && status != -ENODEV)
 856			dev_err(&hdev->dev,
 857				"clear tt %d (%04x) error %d\n",
 858				clear->tt, clear->devinfo, status);
 859
 860		/* Tell the HCD, even if the operation failed */
 861		drv = clear->hcd->driver;
 862		if (drv->clear_tt_buffer_complete)
 863			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 864
 865		kfree(clear);
 866		spin_lock_irqsave(&hub->tt.lock, flags);
 867	}
 868	spin_unlock_irqrestore(&hub->tt.lock, flags);
 869}
 870
 871/**
 872 * usb_hub_set_port_power - control hub port's power state
 873 * @hdev: USB device belonging to the usb hub
 874 * @hub: target hub
 875 * @port1: port index
 876 * @set: expected status
 877 *
 878 * call this function to control port's power via setting or
 879 * clearing the port's PORT_POWER feature.
 880 *
 881 * Return: 0 if successful. A negative error code otherwise.
 882 */
 883int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
 884			   int port1, bool set)
 885{
 886	int ret;
 887
 888	if (set)
 889		ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 890	else
 891		ret = usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 892
 893	if (ret)
 894		return ret;
 895
 896	if (set)
 897		set_bit(port1, hub->power_bits);
 898	else
 899		clear_bit(port1, hub->power_bits);
 900	return 0;
 901}
 902
 903/**
 904 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 905 * @urb: an URB associated with the failed or incomplete split transaction
 906 *
 907 * High speed HCDs use this to tell the hub driver that some split control or
 908 * bulk transaction failed in a way that requires clearing internal state of
 909 * a transaction translator.  This is normally detected (and reported) from
 910 * interrupt context.
 911 *
 912 * It may not be possible for that hub to handle additional full (or low)
 913 * speed transactions until that state is fully cleared out.
 914 *
 915 * Return: 0 if successful. A negative error code otherwise.
 916 */
 917int usb_hub_clear_tt_buffer(struct urb *urb)
 918{
 919	struct usb_device	*udev = urb->dev;
 920	int			pipe = urb->pipe;
 921	struct usb_tt		*tt = udev->tt;
 922	unsigned long		flags;
 923	struct usb_tt_clear	*clear;
 924
 925	/* we've got to cope with an arbitrary number of pending TT clears,
 926	 * since each TT has "at least two" buffers that can need it (and
 927	 * there can be many TTs per hub).  even if they're uncommon.
 928	 */
 929	clear = kmalloc(sizeof *clear, GFP_ATOMIC);
 930	if (clear == NULL) {
 931		dev_err(&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 932		/* FIXME recover somehow ... RESET_TT? */
 933		return -ENOMEM;
 934	}
 935
 936	/* info that CLEAR_TT_BUFFER needs */
 937	clear->tt = tt->multi ? udev->ttport : 1;
 938	clear->devinfo = usb_pipeendpoint (pipe);
 939	clear->devinfo |= ((u16)udev->devaddr) << 4;
 940	clear->devinfo |= usb_pipecontrol(pipe)
 941			? (USB_ENDPOINT_XFER_CONTROL << 11)
 942			: (USB_ENDPOINT_XFER_BULK << 11);
 943	if (usb_pipein(pipe))
 944		clear->devinfo |= 1 << 15;
 945
 946	/* info for completion callback */
 947	clear->hcd = bus_to_hcd(udev->bus);
 948	clear->ep = urb->ep;
 949
 950	/* tell keventd to clear state for this TT */
 951	spin_lock_irqsave(&tt->lock, flags);
 952	list_add_tail(&clear->clear_list, &tt->clear_list);
 953	schedule_work(&tt->clear_work);
 954	spin_unlock_irqrestore(&tt->lock, flags);
 955	return 0;
 956}
 957EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 958
 959static void hub_power_on(struct usb_hub *hub, bool do_delay)
 960{
 961	int port1;
 962
 963	/* Enable power on each port.  Some hubs have reserved values
 964	 * of LPSM (> 2) in their descriptors, even though they are
 965	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
 966	 * but only emulate it.  In all cases, the ports won't work
 967	 * unless we send these messages to the hub.
 968	 */
 969	if (hub_is_port_power_switchable(hub))
 970		dev_dbg(hub->intfdev, "enabling power on all ports\n");
 971	else
 972		dev_dbg(hub->intfdev, "trying to enable port power on "
 973				"non-switchable hub\n");
 974	for (port1 = 1; port1 <= hub->hdev->maxchild; port1++)
 975		if (test_bit(port1, hub->power_bits))
 976			set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 977		else
 978			usb_clear_port_feature(hub->hdev, port1,
 979						USB_PORT_FEAT_POWER);
 980	if (do_delay)
 981		msleep(hub_power_on_good_delay(hub));
 982}
 983
 984static int hub_hub_status(struct usb_hub *hub,
 985		u16 *status, u16 *change)
 986{
 987	int ret;
 988
 989	mutex_lock(&hub->status_mutex);
 990	ret = get_hub_status(hub->hdev, &hub->status->hub);
 991	if (ret < 0) {
 992		if (ret != -ENODEV)
 993			dev_err(hub->intfdev,
 994				"%s failed (err = %d)\n", __func__, ret);
 995	} else {
 996		*status = le16_to_cpu(hub->status->hub.wHubStatus);
 997		*change = le16_to_cpu(hub->status->hub.wHubChange);
 998		ret = 0;
 999	}
1000	mutex_unlock(&hub->status_mutex);
1001	return ret;
1002}
1003
1004static int hub_set_port_link_state(struct usb_hub *hub, int port1,
1005			unsigned int link_status)
1006{
1007	return set_port_feature(hub->hdev,
1008			port1 | (link_status << 3),
1009			USB_PORT_FEAT_LINK_STATE);
1010}
1011
1012/*
1013 * Disable a port and mark a logical connect-change event, so that some
1014 * time later hub_wq will disconnect() any existing usb_device on the port
1015 * and will re-enumerate if there actually is a device attached.
1016 */
1017static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1018{
1019	dev_dbg(&hub->ports[port1 - 1]->dev, "logical disconnect\n");
1020	hub_port_disable(hub, port1, 1);
1021
1022	/* FIXME let caller ask to power down the port:
1023	 *  - some devices won't enumerate without a VBUS power cycle
1024	 *  - SRP saves power that way
1025	 *  - ... new call, TBD ...
1026	 * That's easy if this hub can switch power per-port, and
1027	 * hub_wq reactivates the port later (timer, SRP, etc).
1028	 * Powerdown must be optional, because of reset/DFU.
1029	 */
1030
1031	set_bit(port1, hub->change_bits);
1032	kick_hub_wq(hub);
1033}
1034
1035/**
1036 * usb_remove_device - disable a device's port on its parent hub
1037 * @udev: device to be disabled and removed
1038 * Context: @udev locked, must be able to sleep.
1039 *
1040 * After @udev's port has been disabled, hub_wq is notified and it will
1041 * see that the device has been disconnected.  When the device is
1042 * physically unplugged and something is plugged in, the events will
1043 * be received and processed normally.
1044 *
1045 * Return: 0 if successful. A negative error code otherwise.
1046 */
1047int usb_remove_device(struct usb_device *udev)
1048{
1049	struct usb_hub *hub;
1050	struct usb_interface *intf;
1051	int ret;
1052
1053	if (!udev->parent)	/* Can't remove a root hub */
1054		return -EINVAL;
1055	hub = usb_hub_to_struct_hub(udev->parent);
1056	intf = to_usb_interface(hub->intfdev);
1057
1058	ret = usb_autopm_get_interface(intf);
1059	if (ret < 0)
1060		return ret;
1061
1062	set_bit(udev->portnum, hub->removed_bits);
1063	hub_port_logical_disconnect(hub, udev->portnum);
1064	usb_autopm_put_interface(intf);
1065	return 0;
1066}
1067
1068enum hub_activation_type {
1069	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
1070	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
1071};
1072
1073static void hub_init_func2(struct work_struct *ws);
1074static void hub_init_func3(struct work_struct *ws);
1075
1076static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
1077{
1078	struct usb_device *hdev = hub->hdev;
1079	struct usb_hcd *hcd;
1080	int ret;
1081	int port1;
1082	int status;
1083	bool need_debounce_delay = false;
1084	unsigned delay;
1085
1086	/* Continue a partial initialization */
1087	if (type == HUB_INIT2 || type == HUB_INIT3) {
1088		device_lock(&hdev->dev);
1089
1090		/* Was the hub disconnected while we were waiting? */
1091		if (hub->disconnected)
1092			goto disconnected;
1093		if (type == HUB_INIT2)
1094			goto init2;
1095		goto init3;
1096	}
1097	hub_get(hub);
1098
1099	/* The superspeed hub except for root hub has to use Hub Depth
1100	 * value as an offset into the route string to locate the bits
1101	 * it uses to determine the downstream port number. So hub driver
1102	 * should send a set hub depth request to superspeed hub after
1103	 * the superspeed hub is set configuration in initialization or
1104	 * reset procedure.
1105	 *
1106	 * After a resume, port power should still be on.
1107	 * For any other type of activation, turn it on.
1108	 */
1109	if (type != HUB_RESUME) {
1110		if (hdev->parent && hub_is_superspeed(hdev)) {
1111			ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
1112					HUB_SET_DEPTH, USB_RT_HUB,
1113					hdev->level - 1, 0, NULL, 0,
1114					USB_CTRL_SET_TIMEOUT);
1115			if (ret < 0)
1116				dev_err(hub->intfdev,
1117						"set hub depth failed\n");
1118		}
1119
1120		/* Speed up system boot by using a delayed_work for the
1121		 * hub's initial power-up delays.  This is pretty awkward
1122		 * and the implementation looks like a home-brewed sort of
1123		 * setjmp/longjmp, but it saves at least 100 ms for each
1124		 * root hub (assuming usbcore is compiled into the kernel
1125		 * rather than as a module).  It adds up.
1126		 *
1127		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
1128		 * because for those activation types the ports have to be
1129		 * operational when we return.  In theory this could be done
1130		 * for HUB_POST_RESET, but it's easier not to.
1131		 */
1132		if (type == HUB_INIT) {
1133			delay = hub_power_on_good_delay(hub);
1134
1135			hub_power_on(hub, false);
1136			INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
1137			queue_delayed_work(system_power_efficient_wq,
1138					&hub->init_work,
1139					msecs_to_jiffies(delay));
1140
1141			/* Suppress autosuspend until init is done */
1142			usb_autopm_get_interface_no_resume(
1143					to_usb_interface(hub->intfdev));
1144			return;		/* Continues at init2: below */
1145		} else if (type == HUB_RESET_RESUME) {
1146			/* The internal host controller state for the hub device
1147			 * may be gone after a host power loss on system resume.
1148			 * Update the device's info so the HW knows it's a hub.
1149			 */
1150			hcd = bus_to_hcd(hdev->bus);
1151			if (hcd->driver->update_hub_device) {
1152				ret = hcd->driver->update_hub_device(hcd, hdev,
1153						&hub->tt, GFP_NOIO);
1154				if (ret < 0) {
1155					dev_err(hub->intfdev,
1156						"Host not accepting hub info update\n");
1157					dev_err(hub->intfdev,
1158						"LS/FS devices and hubs may not work under this hub\n");
1159				}
1160			}
1161			hub_power_on(hub, true);
1162		} else {
1163			hub_power_on(hub, true);
1164		}
1165	/* Give some time on remote wakeup to let links to transit to U0 */
1166	} else if (hub_is_superspeed(hub->hdev))
1167		msleep(20);
1168
1169 init2:
1170
1171	/*
1172	 * Check each port and set hub->change_bits to let hub_wq know
1173	 * which ports need attention.
1174	 */
1175	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1176		struct usb_port *port_dev = hub->ports[port1 - 1];
1177		struct usb_device *udev = port_dev->child;
1178		u16 portstatus, portchange;
1179
1180		portstatus = portchange = 0;
1181		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
1182		if (status)
1183			goto abort;
1184
1185		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1186			dev_dbg(&port_dev->dev, "status %04x change %04x\n",
1187					portstatus, portchange);
1188
1189		/*
1190		 * After anything other than HUB_RESUME (i.e., initialization
1191		 * or any sort of reset), every port should be disabled.
1192		 * Unconnected ports should likewise be disabled (paranoia),
1193		 * and so should ports for which we have no usb_device.
1194		 */
1195		if ((portstatus & USB_PORT_STAT_ENABLE) && (
1196				type != HUB_RESUME ||
1197				!(portstatus & USB_PORT_STAT_CONNECTION) ||
1198				!udev ||
1199				udev->state == USB_STATE_NOTATTACHED)) {
1200			/*
1201			 * USB3 protocol ports will automatically transition
1202			 * to Enabled state when detect an USB3.0 device attach.
1203			 * Do not disable USB3 protocol ports, just pretend
1204			 * power was lost
1205			 */
1206			portstatus &= ~USB_PORT_STAT_ENABLE;
1207			if (!hub_is_superspeed(hdev))
1208				usb_clear_port_feature(hdev, port1,
1209						   USB_PORT_FEAT_ENABLE);
1210		}
1211
1212		/* Make sure a warm-reset request is handled by port_event */
1213		if (type == HUB_RESUME &&
1214		    hub_port_warm_reset_required(hub, port1, portstatus))
1215			set_bit(port1, hub->event_bits);
1216
1217		/*
1218		 * Add debounce if USB3 link is in polling/link training state.
1219		 * Link will automatically transition to Enabled state after
1220		 * link training completes.
1221		 */
1222		if (hub_is_superspeed(hdev) &&
1223		    ((portstatus & USB_PORT_STAT_LINK_STATE) ==
1224						USB_SS_PORT_LS_POLLING))
1225			need_debounce_delay = true;
1226
1227		/* Clear status-change flags; we'll debounce later */
1228		if (portchange & USB_PORT_STAT_C_CONNECTION) {
1229			need_debounce_delay = true;
1230			usb_clear_port_feature(hub->hdev, port1,
1231					USB_PORT_FEAT_C_CONNECTION);
1232		}
1233		if (portchange & USB_PORT_STAT_C_ENABLE) {
1234			need_debounce_delay = true;
1235			usb_clear_port_feature(hub->hdev, port1,
1236					USB_PORT_FEAT_C_ENABLE);
1237		}
1238		if (portchange & USB_PORT_STAT_C_RESET) {
1239			need_debounce_delay = true;
1240			usb_clear_port_feature(hub->hdev, port1,
1241					USB_PORT_FEAT_C_RESET);
1242		}
1243		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
1244				hub_is_superspeed(hub->hdev)) {
1245			need_debounce_delay = true;
1246			usb_clear_port_feature(hub->hdev, port1,
1247					USB_PORT_FEAT_C_BH_PORT_RESET);
1248		}
1249		/* We can forget about a "removed" device when there's a
1250		 * physical disconnect or the connect status changes.
1251		 */
1252		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
1253				(portchange & USB_PORT_STAT_C_CONNECTION))
1254			clear_bit(port1, hub->removed_bits);
1255
1256		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
1257			/* Tell hub_wq to disconnect the device or
1258			 * check for a new connection or over current condition.
1259			 * Based on USB2.0 Spec Section 11.12.5,
1260			 * C_PORT_OVER_CURRENT could be set while
1261			 * PORT_OVER_CURRENT is not. So check for any of them.
1262			 */
1263			if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
1264			    (portchange & USB_PORT_STAT_C_CONNECTION) ||
1265			    (portstatus & USB_PORT_STAT_OVERCURRENT) ||
1266			    (portchange & USB_PORT_STAT_C_OVERCURRENT))
1267				set_bit(port1, hub->change_bits);
1268
1269		} else if (portstatus & USB_PORT_STAT_ENABLE) {
1270			bool port_resumed = (portstatus &
1271					USB_PORT_STAT_LINK_STATE) ==
1272				USB_SS_PORT_LS_U0;
1273			/* The power session apparently survived the resume.
1274			 * If there was an overcurrent or suspend change
1275			 * (i.e., remote wakeup request), have hub_wq
1276			 * take care of it.  Look at the port link state
1277			 * for USB 3.0 hubs, since they don't have a suspend
1278			 * change bit, and they don't set the port link change
1279			 * bit on device-initiated resume.
1280			 */
1281			if (portchange || (hub_is_superspeed(hub->hdev) &&
1282						port_resumed))
1283				set_bit(port1, hub->event_bits);
1284
1285		} else if (udev->persist_enabled) {
1286#ifdef CONFIG_PM
1287			udev->reset_resume = 1;
1288#endif
1289			/* Don't set the change_bits when the device
1290			 * was powered off.
1291			 */
1292			if (test_bit(port1, hub->power_bits))
1293				set_bit(port1, hub->change_bits);
1294
1295		} else {
1296			/* The power session is gone; tell hub_wq */
1297			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1298			set_bit(port1, hub->change_bits);
1299		}
1300	}
1301
1302	/* If no port-status-change flags were set, we don't need any
1303	 * debouncing.  If flags were set we can try to debounce the
1304	 * ports all at once right now, instead of letting hub_wq do them
1305	 * one at a time later on.
1306	 *
1307	 * If any port-status changes do occur during this delay, hub_wq
1308	 * will see them later and handle them normally.
1309	 */
1310	if (need_debounce_delay) {
1311		delay = HUB_DEBOUNCE_STABLE;
1312
1313		/* Don't do a long sleep inside a workqueue routine */
1314		if (type == HUB_INIT2) {
1315			INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
1316			queue_delayed_work(system_power_efficient_wq,
1317					&hub->init_work,
1318					msecs_to_jiffies(delay));
1319			device_unlock(&hdev->dev);
1320			return;		/* Continues at init3: below */
1321		} else {
1322			msleep(delay);
1323		}
1324	}
1325 init3:
1326	hub->quiescing = 0;
1327
1328	status = usb_submit_urb(hub->urb, GFP_NOIO);
1329	if (status < 0)
1330		dev_err(hub->intfdev, "activate --> %d\n", status);
1331	if (hub->has_indicators && blinkenlights)
1332		queue_delayed_work(system_power_efficient_wq,
1333				&hub->leds, LED_CYCLE_PERIOD);
1334
1335	/* Scan all ports that need attention */
1336	kick_hub_wq(hub);
1337 abort:
1338	if (type == HUB_INIT2 || type == HUB_INIT3) {
1339		/* Allow autosuspend if it was suppressed */
1340 disconnected:
1341		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1342		device_unlock(&hdev->dev);
1343	}
1344
1345	hub_put(hub);
1346}
1347
1348/* Implement the continuations for the delays above */
1349static void hub_init_func2(struct work_struct *ws)
1350{
1351	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1352
1353	hub_activate(hub, HUB_INIT2);
1354}
1355
1356static void hub_init_func3(struct work_struct *ws)
1357{
1358	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1359
1360	hub_activate(hub, HUB_INIT3);
1361}
1362
1363enum hub_quiescing_type {
1364	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1365};
1366
1367static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1368{
1369	struct usb_device *hdev = hub->hdev;
1370	unsigned long flags;
1371	int i;
1372
1373	/* hub_wq and related activity won't re-trigger */
1374	spin_lock_irqsave(&hub->irq_urb_lock, flags);
1375	hub->quiescing = 1;
1376	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
1377
1378	if (type != HUB_SUSPEND) {
1379		/* Disconnect all the children */
1380		for (i = 0; i < hdev->maxchild; ++i) {
1381			if (hub->ports[i]->child)
1382				usb_disconnect(&hub->ports[i]->child);
1383		}
1384	}
1385
1386	/* Stop hub_wq and related activity */
1387	del_timer_sync(&hub->irq_urb_retry);
1388	usb_kill_urb(hub->urb);
1389	if (hub->has_indicators)
1390		cancel_delayed_work_sync(&hub->leds);
1391	if (hub->tt.hub)
1392		flush_work(&hub->tt.clear_work);
1393}
1394
1395static void hub_pm_barrier_for_all_ports(struct usb_hub *hub)
1396{
1397	int i;
1398
1399	for (i = 0; i < hub->hdev->maxchild; ++i)
1400		pm_runtime_barrier(&hub->ports[i]->dev);
1401}
1402
1403/* caller has locked the hub device */
1404static int hub_pre_reset(struct usb_interface *intf)
1405{
1406	struct usb_hub *hub = usb_get_intfdata(intf);
1407
1408	hub_quiesce(hub, HUB_PRE_RESET);
1409	hub->in_reset = 1;
1410	hub_pm_barrier_for_all_ports(hub);
1411	return 0;
1412}
1413
1414/* caller has locked the hub device */
1415static int hub_post_reset(struct usb_interface *intf)
1416{
1417	struct usb_hub *hub = usb_get_intfdata(intf);
1418
1419	hub->in_reset = 0;
1420	hub_pm_barrier_for_all_ports(hub);
1421	hub_activate(hub, HUB_POST_RESET);
1422	return 0;
1423}
1424
1425static int hub_configure(struct usb_hub *hub,
1426	struct usb_endpoint_descriptor *endpoint)
1427{
1428	struct usb_hcd *hcd;
1429	struct usb_device *hdev = hub->hdev;
1430	struct device *hub_dev = hub->intfdev;
1431	u16 hubstatus, hubchange;
1432	u16 wHubCharacteristics;
1433	unsigned int pipe;
1434	int maxp, ret, i;
1435	char *message = "out of memory";
1436	unsigned unit_load;
1437	unsigned full_load;
1438	unsigned maxchild;
1439
1440	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1441	if (!hub->buffer) {
1442		ret = -ENOMEM;
1443		goto fail;
1444	}
1445
1446	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1447	if (!hub->status) {
1448		ret = -ENOMEM;
1449		goto fail;
1450	}
1451	mutex_init(&hub->status_mutex);
1452
1453	hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1454	if (!hub->descriptor) {
1455		ret = -ENOMEM;
1456		goto fail;
1457	}
1458
1459	/* Request the entire hub descriptor.
1460	 * hub->descriptor can handle USB_MAXCHILDREN ports,
1461	 * but a (non-SS) hub can/will return fewer bytes here.
1462	 */
1463	ret = get_hub_descriptor(hdev, hub->descriptor);
1464	if (ret < 0) {
1465		message = "can't read hub descriptor";
1466		goto fail;
1467	}
1468
1469	maxchild = USB_MAXCHILDREN;
1470	if (hub_is_superspeed(hdev))
1471		maxchild = min_t(unsigned, maxchild, USB_SS_MAXPORTS);
1472
1473	if (hub->descriptor->bNbrPorts > maxchild) {
1474		message = "hub has too many ports!";
1475		ret = -ENODEV;
1476		goto fail;
1477	} else if (hub->descriptor->bNbrPorts == 0) {
1478		message = "hub doesn't have any ports!";
1479		ret = -ENODEV;
1480		goto fail;
1481	}
1482
1483	/*
1484	 * Accumulate wHubDelay + 40ns for every hub in the tree of devices.
1485	 * The resulting value will be used for SetIsochDelay() request.
1486	 */
1487	if (hub_is_superspeed(hdev) || hub_is_superspeedplus(hdev)) {
1488		u32 delay = __le16_to_cpu(hub->descriptor->u.ss.wHubDelay);
1489
1490		if (hdev->parent)
1491			delay += hdev->parent->hub_delay;
1492
1493		delay += USB_TP_TRANSMISSION_DELAY;
1494		hdev->hub_delay = min_t(u32, delay, USB_TP_TRANSMISSION_DELAY_MAX);
1495	}
1496
1497	maxchild = hub->descriptor->bNbrPorts;
1498	dev_info(hub_dev, "%d port%s detected\n", maxchild,
1499			(maxchild == 1) ? "" : "s");
1500
1501	hub->ports = kcalloc(maxchild, sizeof(struct usb_port *), GFP_KERNEL);
1502	if (!hub->ports) {
1503		ret = -ENOMEM;
1504		goto fail;
1505	}
1506
1507	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1508	if (hub_is_superspeed(hdev)) {
1509		unit_load = 150;
1510		full_load = 900;
1511	} else {
1512		unit_load = 100;
1513		full_load = 500;
1514	}
1515
1516	/* FIXME for USB 3.0, skip for now */
1517	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1518			!(hub_is_superspeed(hdev))) {
1519		char	portstr[USB_MAXCHILDREN + 1];
1520
1521		for (i = 0; i < maxchild; i++)
1522			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1523				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1524				? 'F' : 'R';
1525		portstr[maxchild] = 0;
1526		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1527	} else
1528		dev_dbg(hub_dev, "standalone hub\n");
1529
1530	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1531	case HUB_CHAR_COMMON_LPSM:
1532		dev_dbg(hub_dev, "ganged power switching\n");
1533		break;
1534	case HUB_CHAR_INDV_PORT_LPSM:
1535		dev_dbg(hub_dev, "individual port power switching\n");
1536		break;
1537	case HUB_CHAR_NO_LPSM:
1538	case HUB_CHAR_LPSM:
1539		dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1540		break;
1541	}
1542
1543	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1544	case HUB_CHAR_COMMON_OCPM:
1545		dev_dbg(hub_dev, "global over-current protection\n");
1546		break;
1547	case HUB_CHAR_INDV_PORT_OCPM:
1548		dev_dbg(hub_dev, "individual port over-current protection\n");
1549		break;
1550	case HUB_CHAR_NO_OCPM:
1551	case HUB_CHAR_OCPM:
1552		dev_dbg(hub_dev, "no over-current protection\n");
1553		break;
1554	}
1555
1556	spin_lock_init(&hub->tt.lock);
1557	INIT_LIST_HEAD(&hub->tt.clear_list);
1558	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1559	switch (hdev->descriptor.bDeviceProtocol) {
1560	case USB_HUB_PR_FS:
1561		break;
1562	case USB_HUB_PR_HS_SINGLE_TT:
1563		dev_dbg(hub_dev, "Single TT\n");
1564		hub->tt.hub = hdev;
1565		break;
1566	case USB_HUB_PR_HS_MULTI_TT:
1567		ret = usb_set_interface(hdev, 0, 1);
1568		if (ret == 0) {
1569			dev_dbg(hub_dev, "TT per port\n");
1570			hub->tt.multi = 1;
1571		} else
1572			dev_err(hub_dev, "Using single TT (err %d)\n",
1573				ret);
1574		hub->tt.hub = hdev;
1575		break;
1576	case USB_HUB_PR_SS:
1577		/* USB 3.0 hubs don't have a TT */
1578		break;
1579	default:
1580		dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1581			hdev->descriptor.bDeviceProtocol);
1582		break;
1583	}
1584
1585	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1586	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1587	case HUB_TTTT_8_BITS:
1588		if (hdev->descriptor.bDeviceProtocol != 0) {
1589			hub->tt.think_time = 666;
1590			dev_dbg(hub_dev, "TT requires at most %d "
1591					"FS bit times (%d ns)\n",
1592				8, hub->tt.think_time);
1593		}
1594		break;
1595	case HUB_TTTT_16_BITS:
1596		hub->tt.think_time = 666 * 2;
1597		dev_dbg(hub_dev, "TT requires at most %d "
1598				"FS bit times (%d ns)\n",
1599			16, hub->tt.think_time);
1600		break;
1601	case HUB_TTTT_24_BITS:
1602		hub->tt.think_time = 666 * 3;
1603		dev_dbg(hub_dev, "TT requires at most %d "
1604				"FS bit times (%d ns)\n",
1605			24, hub->tt.think_time);
1606		break;
1607	case HUB_TTTT_32_BITS:
1608		hub->tt.think_time = 666 * 4;
1609		dev_dbg(hub_dev, "TT requires at most %d "
1610				"FS bit times (%d ns)\n",
1611			32, hub->tt.think_time);
1612		break;
1613	}
1614
1615	/* probe() zeroes hub->indicator[] */
1616	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1617		hub->has_indicators = 1;
1618		dev_dbg(hub_dev, "Port indicators are supported\n");
1619	}
1620
1621	dev_dbg(hub_dev, "power on to power good time: %dms\n",
1622		hub->descriptor->bPwrOn2PwrGood * 2);
1623
1624	/* power budgeting mostly matters with bus-powered hubs,
1625	 * and battery-powered root hubs (may provide just 8 mA).
1626	 */
1627	ret = usb_get_std_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1628	if (ret) {
1629		message = "can't get hub status";
1630		goto fail;
1631	}
1632	hcd = bus_to_hcd(hdev->bus);
1633	if (hdev == hdev->bus->root_hub) {
1634		if (hcd->power_budget > 0)
1635			hdev->bus_mA = hcd->power_budget;
1636		else
1637			hdev->bus_mA = full_load * maxchild;
1638		if (hdev->bus_mA >= full_load)
1639			hub->mA_per_port = full_load;
1640		else {
1641			hub->mA_per_port = hdev->bus_mA;
1642			hub->limited_power = 1;
1643		}
1644	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1645		int remaining = hdev->bus_mA -
1646			hub->descriptor->bHubContrCurrent;
1647
1648		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1649			hub->descriptor->bHubContrCurrent);
1650		hub->limited_power = 1;
1651
1652		if (remaining < maxchild * unit_load)
1653			dev_warn(hub_dev,
1654					"insufficient power available "
1655					"to use all downstream ports\n");
1656		hub->mA_per_port = unit_load;	/* 7.2.1 */
1657
1658	} else {	/* Self-powered external hub */
1659		/* FIXME: What about battery-powered external hubs that
1660		 * provide less current per port? */
1661		hub->mA_per_port = full_load;
1662	}
1663	if (hub->mA_per_port < full_load)
1664		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1665				hub->mA_per_port);
1666
1667	ret = hub_hub_status(hub, &hubstatus, &hubchange);
1668	if (ret < 0) {
1669		message = "can't get hub status";
1670		goto fail;
1671	}
1672
1673	/* local power status reports aren't always correct */
1674	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1675		dev_dbg(hub_dev, "local power source is %s\n",
1676			(hubstatus & HUB_STATUS_LOCAL_POWER)
1677			? "lost (inactive)" : "good");
1678
1679	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1680		dev_dbg(hub_dev, "%sover-current condition exists\n",
1681			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1682
1683	/* set up the interrupt endpoint
1684	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1685	 * bytes as USB2.0[11.12.3] says because some hubs are known
1686	 * to send more data (and thus cause overflow). For root hubs,
1687	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1688	 * to be big enough for at least USB_MAXCHILDREN ports. */
1689	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1690	maxp = usb_maxpacket(hdev, pipe);
1691
1692	if (maxp > sizeof(*hub->buffer))
1693		maxp = sizeof(*hub->buffer);
1694
1695	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1696	if (!hub->urb) {
1697		ret = -ENOMEM;
1698		goto fail;
1699	}
1700
1701	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1702		hub, endpoint->bInterval);
1703
1704	/* maybe cycle the hub leds */
1705	if (hub->has_indicators && blinkenlights)
1706		hub->indicator[0] = INDICATOR_CYCLE;
1707
1708	mutex_lock(&usb_port_peer_mutex);
1709	for (i = 0; i < maxchild; i++) {
1710		ret = usb_hub_create_port_device(hub, i + 1);
1711		if (ret < 0) {
1712			dev_err(hub->intfdev,
1713				"couldn't create port%d device.\n", i + 1);
1714			break;
1715		}
1716	}
1717	hdev->maxchild = i;
1718	for (i = 0; i < hdev->maxchild; i++) {
1719		struct usb_port *port_dev = hub->ports[i];
1720
1721		pm_runtime_put(&port_dev->dev);
1722	}
1723
1724	mutex_unlock(&usb_port_peer_mutex);
1725	if (ret < 0)
1726		goto fail;
1727
1728	/* Update the HCD's internal representation of this hub before hub_wq
1729	 * starts getting port status changes for devices under the hub.
1730	 */
1731	if (hcd->driver->update_hub_device) {
1732		ret = hcd->driver->update_hub_device(hcd, hdev,
1733				&hub->tt, GFP_KERNEL);
1734		if (ret < 0) {
1735			message = "can't update HCD hub info";
1736			goto fail;
1737		}
1738	}
1739
1740	usb_hub_adjust_deviceremovable(hdev, hub->descriptor);
1741
1742	hub_activate(hub, HUB_INIT);
1743	return 0;
1744
1745fail:
1746	dev_err(hub_dev, "config failed, %s (err %d)\n",
1747			message, ret);
1748	/* hub_disconnect() frees urb and descriptor */
1749	return ret;
1750}
1751
1752static void hub_release(struct kref *kref)
1753{
1754	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1755
1756	usb_put_dev(hub->hdev);
1757	usb_put_intf(to_usb_interface(hub->intfdev));
1758	kfree(hub);
1759}
1760
1761void hub_get(struct usb_hub *hub)
1762{
1763	kref_get(&hub->kref);
1764}
1765
1766void hub_put(struct usb_hub *hub)
1767{
1768	kref_put(&hub->kref, hub_release);
1769}
1770
1771static unsigned highspeed_hubs;
1772
1773static void hub_disconnect(struct usb_interface *intf)
1774{
1775	struct usb_hub *hub = usb_get_intfdata(intf);
1776	struct usb_device *hdev = interface_to_usbdev(intf);
1777	int port1;
1778
1779	/*
1780	 * Stop adding new hub events. We do not want to block here and thus
1781	 * will not try to remove any pending work item.
1782	 */
1783	hub->disconnected = 1;
1784
1785	/* Disconnect all children and quiesce the hub */
1786	hub->error = 0;
1787	hub_quiesce(hub, HUB_DISCONNECT);
1788
1789	mutex_lock(&usb_port_peer_mutex);
1790
1791	/* Avoid races with recursively_mark_NOTATTACHED() */
1792	spin_lock_irq(&device_state_lock);
1793	port1 = hdev->maxchild;
1794	hdev->maxchild = 0;
1795	usb_set_intfdata(intf, NULL);
1796	spin_unlock_irq(&device_state_lock);
1797
1798	for (; port1 > 0; --port1)
1799		usb_hub_remove_port_device(hub, port1);
1800
1801	mutex_unlock(&usb_port_peer_mutex);
1802
1803	if (hub->hdev->speed == USB_SPEED_HIGH)
1804		highspeed_hubs--;
1805
1806	usb_free_urb(hub->urb);
1807	kfree(hub->ports);
1808	kfree(hub->descriptor);
1809	kfree(hub->status);
1810	kfree(hub->buffer);
1811
1812	pm_suspend_ignore_children(&intf->dev, false);
1813
1814	if (hub->quirk_disable_autosuspend)
1815		usb_autopm_put_interface(intf);
1816
1817	onboard_hub_destroy_pdevs(&hub->onboard_hub_devs);
1818
1819	hub_put(hub);
1820}
1821
1822static bool hub_descriptor_is_sane(struct usb_host_interface *desc)
1823{
1824	/* Some hubs have a subclass of 1, which AFAICT according to the */
1825	/*  specs is not defined, but it works */
1826	if (desc->desc.bInterfaceSubClass != 0 &&
1827	    desc->desc.bInterfaceSubClass != 1)
1828		return false;
1829
1830	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
1831	if (desc->desc.bNumEndpoints != 1)
1832		return false;
1833
1834	/* If the first endpoint is not interrupt IN, we'd better punt! */
1835	if (!usb_endpoint_is_int_in(&desc->endpoint[0].desc))
1836		return false;
1837
1838        return true;
1839}
1840
1841static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1842{
1843	struct usb_host_interface *desc;
1844	struct usb_device *hdev;
1845	struct usb_hub *hub;
1846
1847	desc = intf->cur_altsetting;
1848	hdev = interface_to_usbdev(intf);
1849
1850	/*
1851	 * Set default autosuspend delay as 0 to speedup bus suspend,
1852	 * based on the below considerations:
1853	 *
1854	 * - Unlike other drivers, the hub driver does not rely on the
1855	 *   autosuspend delay to provide enough time to handle a wakeup
1856	 *   event, and the submitted status URB is just to check future
1857	 *   change on hub downstream ports, so it is safe to do it.
1858	 *
1859	 * - The patch might cause one or more auto supend/resume for
1860	 *   below very rare devices when they are plugged into hub
1861	 *   first time:
1862	 *
1863	 *   	devices having trouble initializing, and disconnect
1864	 *   	themselves from the bus and then reconnect a second
1865	 *   	or so later
1866	 *
1867	 *   	devices just for downloading firmware, and disconnects
1868	 *   	themselves after completing it
1869	 *
1870	 *   For these quite rare devices, their drivers may change the
1871	 *   autosuspend delay of their parent hub in the probe() to one
1872	 *   appropriate value to avoid the subtle problem if someone
1873	 *   does care it.
1874	 *
1875	 * - The patch may cause one or more auto suspend/resume on
1876	 *   hub during running 'lsusb', but it is probably too
1877	 *   infrequent to worry about.
1878	 *
1879	 * - Change autosuspend delay of hub can avoid unnecessary auto
1880	 *   suspend timer for hub, also may decrease power consumption
1881	 *   of USB bus.
1882	 *
1883	 * - If user has indicated to prevent autosuspend by passing
1884	 *   usbcore.autosuspend = -1 then keep autosuspend disabled.
1885	 */
1886#ifdef CONFIG_PM
1887	if (hdev->dev.power.autosuspend_delay >= 0)
1888		pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
1889#endif
1890
1891	/*
1892	 * Hubs have proper suspend/resume support, except for root hubs
1893	 * where the controller driver doesn't have bus_suspend and
1894	 * bus_resume methods.
1895	 */
1896	if (hdev->parent) {		/* normal device */
1897		usb_enable_autosuspend(hdev);
1898	} else {			/* root hub */
1899		const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
1900
1901		if (drv->bus_suspend && drv->bus_resume)
1902			usb_enable_autosuspend(hdev);
1903	}
1904
1905	if (hdev->level == MAX_TOPO_LEVEL) {
1906		dev_err(&intf->dev,
1907			"Unsupported bus topology: hub nested too deep\n");
1908		return -E2BIG;
1909	}
1910
1911#ifdef	CONFIG_USB_OTG_DISABLE_EXTERNAL_HUB
1912	if (hdev->parent) {
1913		dev_warn(&intf->dev, "ignoring external hub\n");
1914		return -ENODEV;
1915	}
1916#endif
1917
1918	if (!hub_descriptor_is_sane(desc)) {
1919		dev_err(&intf->dev, "bad descriptor, ignoring hub\n");
1920		return -EIO;
1921	}
1922
1923	/* We found a hub */
1924	dev_info(&intf->dev, "USB hub found\n");
1925
1926	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1927	if (!hub)
1928		return -ENOMEM;
1929
1930	kref_init(&hub->kref);
1931	hub->intfdev = &intf->dev;
1932	hub->hdev = hdev;
1933	INIT_DELAYED_WORK(&hub->leds, led_work);
1934	INIT_DELAYED_WORK(&hub->init_work, NULL);
1935	INIT_WORK(&hub->events, hub_event);
1936	INIT_LIST_HEAD(&hub->onboard_hub_devs);
1937	spin_lock_init(&hub->irq_urb_lock);
1938	timer_setup(&hub->irq_urb_retry, hub_retry_irq_urb, 0);
1939	usb_get_intf(intf);
1940	usb_get_dev(hdev);
1941
1942	usb_set_intfdata(intf, hub);
1943	intf->needs_remote_wakeup = 1;
1944	pm_suspend_ignore_children(&intf->dev, true);
1945
1946	if (hdev->speed == USB_SPEED_HIGH)
1947		highspeed_hubs++;
1948
1949	if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
1950		hub->quirk_check_port_auto_suspend = 1;
1951
1952	if (id->driver_info & HUB_QUIRK_DISABLE_AUTOSUSPEND) {
1953		hub->quirk_disable_autosuspend = 1;
1954		usb_autopm_get_interface_no_resume(intf);
1955	}
1956
1957	if ((id->driver_info & HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL) &&
1958	    desc->endpoint[0].desc.bInterval > USB_REDUCE_FRAME_INTR_BINTERVAL) {
1959		desc->endpoint[0].desc.bInterval =
1960			USB_REDUCE_FRAME_INTR_BINTERVAL;
1961		/* Tell the HCD about the interrupt ep's new bInterval */
1962		usb_set_interface(hdev, 0, 0);
1963	}
1964
1965	if (hub_configure(hub, &desc->endpoint[0].desc) >= 0) {
1966		onboard_hub_create_pdevs(hdev, &hub->onboard_hub_devs);
1967
1968		return 0;
1969	}
1970
1971	hub_disconnect(intf);
1972	return -ENODEV;
1973}
1974
1975static int
1976hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1977{
1978	struct usb_device *hdev = interface_to_usbdev(intf);
1979	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1980
1981	/* assert ifno == 0 (part of hub spec) */
1982	switch (code) {
1983	case USBDEVFS_HUB_PORTINFO: {
1984		struct usbdevfs_hub_portinfo *info = user_data;
1985		int i;
1986
1987		spin_lock_irq(&device_state_lock);
1988		if (hdev->devnum <= 0)
1989			info->nports = 0;
1990		else {
1991			info->nports = hdev->maxchild;
1992			for (i = 0; i < info->nports; i++) {
1993				if (hub->ports[i]->child == NULL)
1994					info->port[i] = 0;
1995				else
1996					info->port[i] =
1997						hub->ports[i]->child->devnum;
1998			}
1999		}
2000		spin_unlock_irq(&device_state_lock);
2001
2002		return info->nports + 1;
2003		}
2004
2005	default:
2006		return -ENOSYS;
2007	}
2008}
2009
2010/*
2011 * Allow user programs to claim ports on a hub.  When a device is attached
2012 * to one of these "claimed" ports, the program will "own" the device.
2013 */
2014static int find_port_owner(struct usb_device *hdev, unsigned port1,
2015		struct usb_dev_state ***ppowner)
2016{
2017	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
2018
2019	if (hdev->state == USB_STATE_NOTATTACHED)
2020		return -ENODEV;
2021	if (port1 == 0 || port1 > hdev->maxchild)
2022		return -EINVAL;
2023
2024	/* Devices not managed by the hub driver
2025	 * will always have maxchild equal to 0.
2026	 */
2027	*ppowner = &(hub->ports[port1 - 1]->port_owner);
2028	return 0;
2029}
2030
2031/* In the following three functions, the caller must hold hdev's lock */
2032int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
2033		       struct usb_dev_state *owner)
2034{
2035	int rc;
2036	struct usb_dev_state **powner;
2037
2038	rc = find_port_owner(hdev, port1, &powner);
2039	if (rc)
2040		return rc;
2041	if (*powner)
2042		return -EBUSY;
2043	*powner = owner;
2044	return rc;
2045}
2046EXPORT_SYMBOL_GPL(usb_hub_claim_port);
2047
2048int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
2049			 struct usb_dev_state *owner)
2050{
2051	int rc;
2052	struct usb_dev_state **powner;
2053
2054	rc = find_port_owner(hdev, port1, &powner);
2055	if (rc)
2056		return rc;
2057	if (*powner != owner)
2058		return -ENOENT;
2059	*powner = NULL;
2060	return rc;
2061}
2062EXPORT_SYMBOL_GPL(usb_hub_release_port);
2063
2064void usb_hub_release_all_ports(struct usb_device *hdev, struct usb_dev_state *owner)
2065{
2066	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
2067	int n;
2068
2069	for (n = 0; n < hdev->maxchild; n++) {
2070		if (hub->ports[n]->port_owner == owner)
2071			hub->ports[n]->port_owner = NULL;
2072	}
2073
2074}
2075
2076/* The caller must hold udev's lock */
2077bool usb_device_is_owned(struct usb_device *udev)
2078{
2079	struct usb_hub *hub;
2080
2081	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
2082		return false;
2083	hub = usb_hub_to_struct_hub(udev->parent);
2084	return !!hub->ports[udev->portnum - 1]->port_owner;
2085}
2086
2087static void update_port_device_state(struct usb_device *udev)
2088{
2089	struct usb_hub *hub;
2090	struct usb_port *port_dev;
2091
2092	if (udev->parent) {
2093		hub = usb_hub_to_struct_hub(udev->parent);
2094
2095		/*
2096		 * The Link Layer Validation System Driver (lvstest)
2097		 * has a test step to unbind the hub before running the
2098		 * rest of the procedure. This triggers hub_disconnect
2099		 * which will set the hub's maxchild to 0, further
2100		 * resulting in usb_hub_to_struct_hub returning NULL.
2101		 */
2102		if (hub) {
2103			port_dev = hub->ports[udev->portnum - 1];
2104			WRITE_ONCE(port_dev->state, udev->state);
2105			sysfs_notify_dirent(port_dev->state_kn);
2106		}
2107	}
2108}
2109
2110static void recursively_mark_NOTATTACHED(struct usb_device *udev)
2111{
2112	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2113	int i;
2114
2115	for (i = 0; i < udev->maxchild; ++i) {
2116		if (hub->ports[i]->child)
2117			recursively_mark_NOTATTACHED(hub->ports[i]->child);
2118	}
2119	if (udev->state == USB_STATE_SUSPENDED)
2120		udev->active_duration -= jiffies;
2121	udev->state = USB_STATE_NOTATTACHED;
2122	update_port_device_state(udev);
2123}
2124
2125/**
2126 * usb_set_device_state - change a device's current state (usbcore, hcds)
2127 * @udev: pointer to device whose state should be changed
2128 * @new_state: new state value to be stored
2129 *
2130 * udev->state is _not_ fully protected by the device lock.  Although
2131 * most transitions are made only while holding the lock, the state can
2132 * can change to USB_STATE_NOTATTACHED at almost any time.  This
2133 * is so that devices can be marked as disconnected as soon as possible,
2134 * without having to wait for any semaphores to be released.  As a result,
2135 * all changes to any device's state must be protected by the
2136 * device_state_lock spinlock.
2137 *
2138 * Once a device has been added to the device tree, all changes to its state
2139 * should be made using this routine.  The state should _not_ be set directly.
2140 *
2141 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
2142 * Otherwise udev->state is set to new_state, and if new_state is
2143 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
2144 * to USB_STATE_NOTATTACHED.
2145 */
2146void usb_set_device_state(struct usb_device *udev,
2147		enum usb_device_state new_state)
2148{
2149	unsigned long flags;
2150	int wakeup = -1;
2151
2152	spin_lock_irqsave(&device_state_lock, flags);
2153	if (udev->state == USB_STATE_NOTATTACHED)
2154		;	/* do nothing */
2155	else if (new_state != USB_STATE_NOTATTACHED) {
2156
2157		/* root hub wakeup capabilities are managed out-of-band
2158		 * and may involve silicon errata ... ignore them here.
2159		 */
2160		if (udev->parent) {
2161			if (udev->state == USB_STATE_SUSPENDED
2162					|| new_state == USB_STATE_SUSPENDED)
2163				;	/* No change to wakeup settings */
2164			else if (new_state == USB_STATE_CONFIGURED)
2165				wakeup = (udev->quirks &
2166					USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
2167					udev->actconfig->desc.bmAttributes &
2168					USB_CONFIG_ATT_WAKEUP;
2169			else
2170				wakeup = 0;
2171		}
2172		if (udev->state == USB_STATE_SUSPENDED &&
2173			new_state != USB_STATE_SUSPENDED)
2174			udev->active_duration -= jiffies;
2175		else if (new_state == USB_STATE_SUSPENDED &&
2176				udev->state != USB_STATE_SUSPENDED)
2177			udev->active_duration += jiffies;
2178		udev->state = new_state;
2179		update_port_device_state(udev);
2180	} else
2181		recursively_mark_NOTATTACHED(udev);
2182	spin_unlock_irqrestore(&device_state_lock, flags);
2183	if (wakeup >= 0)
2184		device_set_wakeup_capable(&udev->dev, wakeup);
2185}
2186EXPORT_SYMBOL_GPL(usb_set_device_state);
2187
2188/*
2189 * Choose a device number.
2190 *
2191 * Device numbers are used as filenames in usbfs.  On USB-1.1 and
2192 * USB-2.0 buses they are also used as device addresses, however on
2193 * USB-3.0 buses the address is assigned by the controller hardware
2194 * and it usually is not the same as the device number.
2195 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2196 * Devices connected under xHCI are not as simple.  The host controller
2197 * supports virtualization, so the hardware assigns device addresses and
2198 * the HCD must setup data structures before issuing a set address
2199 * command to the hardware.
2200 */
2201static void choose_devnum(struct usb_device *udev)
2202{
2203	int		devnum;
2204	struct usb_bus	*bus = udev->bus;
2205
2206	/* be safe when more hub events are proceed in parallel */
2207	mutex_lock(&bus->devnum_next_mutex);
2208
2209	/* Try to allocate the next devnum beginning at bus->devnum_next. */
2210	devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
2211			bus->devnum_next);
2212	if (devnum >= 128)
2213		devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
2214	bus->devnum_next = (devnum >= 127 ? 1 : devnum + 1);
 
 
 
 
 
 
2215	if (devnum < 128) {
2216		set_bit(devnum, bus->devmap.devicemap);
2217		udev->devnum = devnum;
2218	}
2219	mutex_unlock(&bus->devnum_next_mutex);
2220}
2221
2222static void release_devnum(struct usb_device *udev)
2223{
2224	if (udev->devnum > 0) {
2225		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
2226		udev->devnum = -1;
2227	}
2228}
2229
2230static void update_devnum(struct usb_device *udev, int devnum)
2231{
2232	udev->devnum = devnum;
 
 
2233	if (!udev->devaddr)
2234		udev->devaddr = (u8)devnum;
2235}
2236
2237static void hub_free_dev(struct usb_device *udev)
2238{
2239	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2240
2241	/* Root hubs aren't real devices, so don't free HCD resources */
2242	if (hcd->driver->free_dev && udev->parent)
2243		hcd->driver->free_dev(hcd, udev);
2244}
2245
2246static void hub_disconnect_children(struct usb_device *udev)
2247{
2248	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2249	int i;
2250
2251	/* Free up all the children before we remove this device */
2252	for (i = 0; i < udev->maxchild; i++) {
2253		if (hub->ports[i]->child)
2254			usb_disconnect(&hub->ports[i]->child);
2255	}
2256}
2257
2258/**
2259 * usb_disconnect - disconnect a device (usbcore-internal)
2260 * @pdev: pointer to device being disconnected
2261 *
2262 * Context: task context, might sleep
2263 *
2264 * Something got disconnected. Get rid of it and all of its children.
2265 *
2266 * If *pdev is a normal device then the parent hub must already be locked.
2267 * If *pdev is a root hub then the caller must hold the usb_bus_idr_lock,
2268 * which protects the set of root hubs as well as the list of buses.
2269 *
2270 * Only hub drivers (including virtual root hub drivers for host
2271 * controllers) should ever call this.
2272 *
2273 * This call is synchronous, and may not be used in an interrupt context.
2274 */
2275void usb_disconnect(struct usb_device **pdev)
2276{
2277	struct usb_port *port_dev = NULL;
2278	struct usb_device *udev = *pdev;
2279	struct usb_hub *hub = NULL;
2280	int port1 = 1;
2281
2282	/* mark the device as inactive, so any further urb submissions for
2283	 * this device (and any of its children) will fail immediately.
2284	 * this quiesces everything except pending urbs.
2285	 */
2286	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2287	dev_info(&udev->dev, "USB disconnect, device number %d\n",
2288			udev->devnum);
2289
2290	/*
2291	 * Ensure that the pm runtime code knows that the USB device
2292	 * is in the process of being disconnected.
2293	 */
2294	pm_runtime_barrier(&udev->dev);
2295
2296	usb_lock_device(udev);
2297
2298	hub_disconnect_children(udev);
2299
2300	/* deallocate hcd/hardware state ... nuking all pending urbs and
2301	 * cleaning up all state associated with the current configuration
2302	 * so that the hardware is now fully quiesced.
2303	 */
2304	dev_dbg(&udev->dev, "unregistering device\n");
2305	usb_disable_device(udev, 0);
2306	usb_hcd_synchronize_unlinks(udev);
2307
2308	if (udev->parent) {
2309		port1 = udev->portnum;
2310		hub = usb_hub_to_struct_hub(udev->parent);
2311		port_dev = hub->ports[port1 - 1];
2312
2313		sysfs_remove_link(&udev->dev.kobj, "port");
2314		sysfs_remove_link(&port_dev->dev.kobj, "device");
2315
2316		/*
2317		 * As usb_port_runtime_resume() de-references udev, make
2318		 * sure no resumes occur during removal
2319		 */
2320		if (!test_and_set_bit(port1, hub->child_usage_bits))
2321			pm_runtime_get_sync(&port_dev->dev);
2322
2323		typec_deattach(port_dev->connector, &udev->dev);
2324	}
2325
2326	usb_remove_ep_devs(&udev->ep0);
2327	usb_unlock_device(udev);
2328
2329	/* Unregister the device.  The device driver is responsible
2330	 * for de-configuring the device and invoking the remove-device
2331	 * notifier chain (used by usbfs and possibly others).
2332	 */
2333	device_del(&udev->dev);
2334
2335	/* Free the device number and delete the parent's children[]
2336	 * (or root_hub) pointer.
2337	 */
2338	release_devnum(udev);
2339
2340	/* Avoid races with recursively_mark_NOTATTACHED() */
2341	spin_lock_irq(&device_state_lock);
2342	*pdev = NULL;
2343	spin_unlock_irq(&device_state_lock);
2344
2345	if (port_dev && test_and_clear_bit(port1, hub->child_usage_bits))
2346		pm_runtime_put(&port_dev->dev);
2347
2348	hub_free_dev(udev);
2349
2350	put_device(&udev->dev);
2351}
2352
2353#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
2354static void show_string(struct usb_device *udev, char *id, char *string)
2355{
2356	if (!string)
2357		return;
2358	dev_info(&udev->dev, "%s: %s\n", id, string);
2359}
2360
2361static void announce_device(struct usb_device *udev)
2362{
2363	u16 bcdDevice = le16_to_cpu(udev->descriptor.bcdDevice);
2364
2365	dev_info(&udev->dev,
2366		"New USB device found, idVendor=%04x, idProduct=%04x, bcdDevice=%2x.%02x\n",
2367		le16_to_cpu(udev->descriptor.idVendor),
2368		le16_to_cpu(udev->descriptor.idProduct),
2369		bcdDevice >> 8, bcdDevice & 0xff);
2370	dev_info(&udev->dev,
2371		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
2372		udev->descriptor.iManufacturer,
2373		udev->descriptor.iProduct,
2374		udev->descriptor.iSerialNumber);
2375	show_string(udev, "Product", udev->product);
2376	show_string(udev, "Manufacturer", udev->manufacturer);
2377	show_string(udev, "SerialNumber", udev->serial);
2378}
2379#else
2380static inline void announce_device(struct usb_device *udev) { }
2381#endif
2382
2383
2384/**
2385 * usb_enumerate_device_otg - FIXME (usbcore-internal)
2386 * @udev: newly addressed device (in ADDRESS state)
2387 *
2388 * Finish enumeration for On-The-Go devices
2389 *
2390 * Return: 0 if successful. A negative error code otherwise.
2391 */
2392static int usb_enumerate_device_otg(struct usb_device *udev)
2393{
2394	int err = 0;
2395
2396#ifdef	CONFIG_USB_OTG
2397	/*
2398	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
2399	 * to wake us after we've powered off VBUS; and HNP, switching roles
2400	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
2401	 */
2402	if (!udev->bus->is_b_host
2403			&& udev->config
2404			&& udev->parent == udev->bus->root_hub) {
2405		struct usb_otg_descriptor	*desc = NULL;
2406		struct usb_bus			*bus = udev->bus;
2407		unsigned			port1 = udev->portnum;
2408
2409		/* descriptor may appear anywhere in config */
2410		err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
2411				le16_to_cpu(udev->config[0].desc.wTotalLength),
2412				USB_DT_OTG, (void **) &desc, sizeof(*desc));
2413		if (err || !(desc->bmAttributes & USB_OTG_HNP))
2414			return 0;
2415
2416		dev_info(&udev->dev, "Dual-Role OTG device on %sHNP port\n",
2417					(port1 == bus->otg_port) ? "" : "non-");
2418
2419		/* enable HNP before suspend, it's simpler */
2420		if (port1 == bus->otg_port) {
2421			bus->b_hnp_enable = 1;
2422			err = usb_control_msg(udev,
2423				usb_sndctrlpipe(udev, 0),
2424				USB_REQ_SET_FEATURE, 0,
2425				USB_DEVICE_B_HNP_ENABLE,
2426				0, NULL, 0,
2427				USB_CTRL_SET_TIMEOUT);
2428			if (err < 0) {
2429				/*
2430				 * OTG MESSAGE: report errors here,
2431				 * customize to match your product.
2432				 */
2433				dev_err(&udev->dev, "can't set HNP mode: %d\n",
2434									err);
2435				bus->b_hnp_enable = 0;
2436			}
2437		} else if (desc->bLength == sizeof
2438				(struct usb_otg_descriptor)) {
2439			/*
2440			 * We are operating on a legacy OTP device
2441			 * These should be told that they are operating
2442			 * on the wrong port if we have another port that does
2443			 * support HNP
2444			 */
2445			if (bus->otg_port != 0) {
2446				/* Set a_alt_hnp_support for legacy otg device */
2447				err = usb_control_msg(udev,
2448					usb_sndctrlpipe(udev, 0),
2449					USB_REQ_SET_FEATURE, 0,
2450					USB_DEVICE_A_ALT_HNP_SUPPORT,
2451					0, NULL, 0,
2452					USB_CTRL_SET_TIMEOUT);
2453				if (err < 0)
2454					dev_err(&udev->dev,
2455						"set a_alt_hnp_support failed: %d\n",
2456						err);
2457			}
2458		}
2459	}
2460#endif
2461	return err;
2462}
2463
2464
2465/**
2466 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
2467 * @udev: newly addressed device (in ADDRESS state)
2468 *
2469 * This is only called by usb_new_device() -- all comments that apply there
2470 * apply here wrt to environment.
 
2471 *
2472 * If the device is WUSB and not authorized, we don't attempt to read
2473 * the string descriptors, as they will be errored out by the device
2474 * until it has been authorized.
2475 *
2476 * Return: 0 if successful. A negative error code otherwise.
2477 */
2478static int usb_enumerate_device(struct usb_device *udev)
2479{
2480	int err;
2481	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2482
2483	if (udev->config == NULL) {
2484		err = usb_get_configuration(udev);
2485		if (err < 0) {
2486			if (err != -ENODEV)
2487				dev_err(&udev->dev, "can't read configurations, error %d\n",
2488						err);
2489			return err;
2490		}
2491	}
2492
2493	/* read the standard strings and cache them if present */
2494	udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
2495	udev->manufacturer = usb_cache_string(udev,
2496					      udev->descriptor.iManufacturer);
2497	udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
2498
2499	err = usb_enumerate_device_otg(udev);
2500	if (err < 0)
2501		return err;
2502
2503	if (IS_ENABLED(CONFIG_USB_OTG_PRODUCTLIST) && hcd->tpl_support &&
2504		!is_targeted(udev)) {
2505		/* Maybe it can talk to us, though we can't talk to it.
2506		 * (Includes HNP test device.)
2507		 */
2508		if (IS_ENABLED(CONFIG_USB_OTG) && (udev->bus->b_hnp_enable
2509			|| udev->bus->is_b_host)) {
2510			err = usb_port_suspend(udev, PMSG_AUTO_SUSPEND);
2511			if (err < 0)
2512				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
2513		}
2514		return -ENOTSUPP;
2515	}
2516
2517	usb_detect_interface_quirks(udev);
2518
2519	return 0;
2520}
2521
2522static void set_usb_port_removable(struct usb_device *udev)
2523{
2524	struct usb_device *hdev = udev->parent;
2525	struct usb_hub *hub;
2526	u8 port = udev->portnum;
2527	u16 wHubCharacteristics;
2528	bool removable = true;
2529
2530	dev_set_removable(&udev->dev, DEVICE_REMOVABLE_UNKNOWN);
2531
2532	if (!hdev)
2533		return;
2534
2535	hub = usb_hub_to_struct_hub(udev->parent);
2536
2537	/*
2538	 * If the platform firmware has provided information about a port,
2539	 * use that to determine whether it's removable.
2540	 */
2541	switch (hub->ports[udev->portnum - 1]->connect_type) {
2542	case USB_PORT_CONNECT_TYPE_HOT_PLUG:
2543		dev_set_removable(&udev->dev, DEVICE_REMOVABLE);
2544		return;
2545	case USB_PORT_CONNECT_TYPE_HARD_WIRED:
2546	case USB_PORT_NOT_USED:
2547		dev_set_removable(&udev->dev, DEVICE_FIXED);
2548		return;
2549	default:
2550		break;
2551	}
2552
2553	/*
2554	 * Otherwise, check whether the hub knows whether a port is removable
2555	 * or not
2556	 */
2557	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2558
2559	if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
2560		return;
2561
2562	if (hub_is_superspeed(hdev)) {
2563		if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
2564				& (1 << port))
2565			removable = false;
2566	} else {
2567		if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
2568			removable = false;
2569	}
2570
2571	if (removable)
2572		dev_set_removable(&udev->dev, DEVICE_REMOVABLE);
2573	else
2574		dev_set_removable(&udev->dev, DEVICE_FIXED);
2575
2576}
2577
2578/**
2579 * usb_new_device - perform initial device setup (usbcore-internal)
2580 * @udev: newly addressed device (in ADDRESS state)
2581 *
2582 * This is called with devices which have been detected but not fully
2583 * enumerated.  The device descriptor is available, but not descriptors
2584 * for any device configuration.  The caller must have locked either
2585 * the parent hub (if udev is a normal device) or else the
2586 * usb_bus_idr_lock (if udev is a root hub).  The parent's pointer to
2587 * udev has already been installed, but udev is not yet visible through
2588 * sysfs or other filesystem code.
2589 *
2590 * This call is synchronous, and may not be used in an interrupt context.
2591 *
2592 * Only the hub driver or root-hub registrar should ever call this.
2593 *
2594 * Return: Whether the device is configured properly or not. Zero if the
2595 * interface was registered with the driver core; else a negative errno
2596 * value.
2597 *
2598 */
2599int usb_new_device(struct usb_device *udev)
2600{
2601	int err;
2602
2603	if (udev->parent) {
2604		/* Initialize non-root-hub device wakeup to disabled;
2605		 * device (un)configuration controls wakeup capable
2606		 * sysfs power/wakeup controls wakeup enabled/disabled
2607		 */
2608		device_init_wakeup(&udev->dev, 0);
2609	}
2610
2611	/* Tell the runtime-PM framework the device is active */
2612	pm_runtime_set_active(&udev->dev);
2613	pm_runtime_get_noresume(&udev->dev);
2614	pm_runtime_use_autosuspend(&udev->dev);
2615	pm_runtime_enable(&udev->dev);
2616
2617	/* By default, forbid autosuspend for all devices.  It will be
2618	 * allowed for hubs during binding.
2619	 */
2620	usb_disable_autosuspend(udev);
2621
2622	err = usb_enumerate_device(udev);	/* Read descriptors */
2623	if (err < 0)
2624		goto fail;
2625	dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2626			udev->devnum, udev->bus->busnum,
2627			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2628	/* export the usbdev device-node for libusb */
2629	udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2630			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2631
2632	/* Tell the world! */
2633	announce_device(udev);
2634
2635	if (udev->serial)
2636		add_device_randomness(udev->serial, strlen(udev->serial));
2637	if (udev->product)
2638		add_device_randomness(udev->product, strlen(udev->product));
2639	if (udev->manufacturer)
2640		add_device_randomness(udev->manufacturer,
2641				      strlen(udev->manufacturer));
2642
2643	device_enable_async_suspend(&udev->dev);
2644
2645	/* check whether the hub or firmware marks this port as non-removable */
2646	set_usb_port_removable(udev);
2647
2648	/* Register the device.  The device driver is responsible
2649	 * for configuring the device and invoking the add-device
2650	 * notifier chain (used by usbfs and possibly others).
2651	 */
2652	err = device_add(&udev->dev);
2653	if (err) {
2654		dev_err(&udev->dev, "can't device_add, error %d\n", err);
2655		goto fail;
2656	}
2657
2658	/* Create link files between child device and usb port device. */
2659	if (udev->parent) {
2660		struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
2661		int port1 = udev->portnum;
2662		struct usb_port	*port_dev = hub->ports[port1 - 1];
2663
2664		err = sysfs_create_link(&udev->dev.kobj,
2665				&port_dev->dev.kobj, "port");
2666		if (err)
2667			goto fail;
2668
2669		err = sysfs_create_link(&port_dev->dev.kobj,
2670				&udev->dev.kobj, "device");
2671		if (err) {
2672			sysfs_remove_link(&udev->dev.kobj, "port");
2673			goto fail;
2674		}
2675
2676		if (!test_and_set_bit(port1, hub->child_usage_bits))
2677			pm_runtime_get_sync(&port_dev->dev);
2678
2679		typec_attach(port_dev->connector, &udev->dev);
2680	}
2681
2682	(void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2683	usb_mark_last_busy(udev);
2684	pm_runtime_put_sync_autosuspend(&udev->dev);
2685	return err;
2686
2687fail:
2688	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2689	pm_runtime_disable(&udev->dev);
2690	pm_runtime_set_suspended(&udev->dev);
2691	return err;
2692}
2693
2694
2695/**
2696 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2697 * @usb_dev: USB device
2698 *
2699 * Move the USB device to a very basic state where interfaces are disabled
2700 * and the device is in fact unconfigured and unusable.
2701 *
2702 * We share a lock (that we have) with device_del(), so we need to
2703 * defer its call.
2704 *
2705 * Return: 0.
2706 */
2707int usb_deauthorize_device(struct usb_device *usb_dev)
2708{
2709	usb_lock_device(usb_dev);
2710	if (usb_dev->authorized == 0)
2711		goto out_unauthorized;
2712
2713	usb_dev->authorized = 0;
2714	usb_set_configuration(usb_dev, -1);
2715
2716out_unauthorized:
2717	usb_unlock_device(usb_dev);
2718	return 0;
2719}
2720
2721
2722int usb_authorize_device(struct usb_device *usb_dev)
2723{
2724	int result = 0, c;
2725
2726	usb_lock_device(usb_dev);
2727	if (usb_dev->authorized == 1)
2728		goto out_authorized;
2729
2730	result = usb_autoresume_device(usb_dev);
2731	if (result < 0) {
2732		dev_err(&usb_dev->dev,
2733			"can't autoresume for authorization: %d\n", result);
2734		goto error_autoresume;
2735	}
2736
 
 
 
 
 
 
 
 
 
2737	usb_dev->authorized = 1;
2738	/* Choose and set the configuration.  This registers the interfaces
2739	 * with the driver core and lets interface drivers bind to them.
2740	 */
2741	c = usb_choose_configuration(usb_dev);
2742	if (c >= 0) {
2743		result = usb_set_configuration(usb_dev, c);
2744		if (result) {
2745			dev_err(&usb_dev->dev,
2746				"can't set config #%d, error %d\n", c, result);
2747			/* This need not be fatal.  The user can try to
2748			 * set other configurations. */
2749		}
2750	}
2751	dev_info(&usb_dev->dev, "authorized to connect\n");
2752
 
2753	usb_autosuspend_device(usb_dev);
2754error_autoresume:
2755out_authorized:
2756	usb_unlock_device(usb_dev);	/* complements locktree */
2757	return result;
2758}
2759
2760/**
2761 * get_port_ssp_rate - Match the extended port status to SSP rate
2762 * @hdev: The hub device
2763 * @ext_portstatus: extended port status
2764 *
2765 * Match the extended port status speed id to the SuperSpeed Plus sublink speed
2766 * capability attributes. Base on the number of connected lanes and speed,
2767 * return the corresponding enum usb_ssp_rate.
2768 */
2769static enum usb_ssp_rate get_port_ssp_rate(struct usb_device *hdev,
2770					   u32 ext_portstatus)
2771{
2772	struct usb_ssp_cap_descriptor *ssp_cap;
2773	u32 attr;
2774	u8 speed_id;
2775	u8 ssac;
2776	u8 lanes;
2777	int i;
2778
2779	if (!hdev->bos)
2780		goto out;
2781
2782	ssp_cap = hdev->bos->ssp_cap;
2783	if (!ssp_cap)
2784		goto out;
2785
2786	speed_id = ext_portstatus & USB_EXT_PORT_STAT_RX_SPEED_ID;
2787	lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2788
2789	ssac = le32_to_cpu(ssp_cap->bmAttributes) &
2790		USB_SSP_SUBLINK_SPEED_ATTRIBS;
2791
2792	for (i = 0; i <= ssac; i++) {
2793		u8 ssid;
2794
2795		attr = le32_to_cpu(ssp_cap->bmSublinkSpeedAttr[i]);
2796		ssid = FIELD_GET(USB_SSP_SUBLINK_SPEED_SSID, attr);
2797		if (speed_id == ssid) {
2798			u16 mantissa;
2799			u8 lse;
2800			u8 type;
2801
2802			/*
2803			 * Note: currently asymmetric lane types are only
2804			 * applicable for SSIC operate in SuperSpeed protocol
2805			 */
2806			type = FIELD_GET(USB_SSP_SUBLINK_SPEED_ST, attr);
2807			if (type == USB_SSP_SUBLINK_SPEED_ST_ASYM_RX ||
2808			    type == USB_SSP_SUBLINK_SPEED_ST_ASYM_TX)
2809				goto out;
2810
2811			if (FIELD_GET(USB_SSP_SUBLINK_SPEED_LP, attr) !=
2812			    USB_SSP_SUBLINK_SPEED_LP_SSP)
2813				goto out;
2814
2815			lse = FIELD_GET(USB_SSP_SUBLINK_SPEED_LSE, attr);
2816			mantissa = FIELD_GET(USB_SSP_SUBLINK_SPEED_LSM, attr);
2817
2818			/* Convert to Gbps */
2819			for (; lse < USB_SSP_SUBLINK_SPEED_LSE_GBPS; lse++)
2820				mantissa /= 1000;
2821
2822			if (mantissa >= 10 && lanes == 1)
2823				return USB_SSP_GEN_2x1;
2824
2825			if (mantissa >= 10 && lanes == 2)
2826				return USB_SSP_GEN_2x2;
2827
2828			if (mantissa >= 5 && lanes == 2)
2829				return USB_SSP_GEN_1x2;
2830
2831			goto out;
2832		}
2833	}
2834
2835out:
2836	return USB_SSP_GEN_UNKNOWN;
2837}
2838
 
 
 
 
 
 
 
 
 
 
 
2839#ifdef CONFIG_USB_FEW_INIT_RETRIES
2840#define PORT_RESET_TRIES	2
2841#define SET_ADDRESS_TRIES	1
2842#define GET_DESCRIPTOR_TRIES	1
2843#define GET_MAXPACKET0_TRIES	1
2844#define PORT_INIT_TRIES		4
2845
2846#else
2847#define PORT_RESET_TRIES	5
2848#define SET_ADDRESS_TRIES	2
2849#define GET_DESCRIPTOR_TRIES	2
2850#define GET_MAXPACKET0_TRIES	3
2851#define PORT_INIT_TRIES		4
2852#endif	/* CONFIG_USB_FEW_INIT_RETRIES */
2853
2854#define DETECT_DISCONNECT_TRIES 5
2855
2856#define HUB_ROOT_RESET_TIME	60	/* times are in msec */
2857#define HUB_SHORT_RESET_TIME	10
2858#define HUB_BH_RESET_TIME	50
2859#define HUB_LONG_RESET_TIME	200
2860#define HUB_RESET_TIMEOUT	800
2861
2862static bool use_new_scheme(struct usb_device *udev, int retry,
2863			   struct usb_port *port_dev)
2864{
2865	int old_scheme_first_port =
2866		(port_dev->quirks & USB_PORT_QUIRK_OLD_SCHEME) ||
2867		old_scheme_first;
2868
2869	/*
2870	 * "New scheme" enumeration causes an extra state transition to be
2871	 * exposed to an xhci host and causes USB3 devices to receive control
2872	 * commands in the default state.  This has been seen to cause
2873	 * enumeration failures, so disable this enumeration scheme for USB3
2874	 * devices.
2875	 */
2876	if (udev->speed >= USB_SPEED_SUPER)
2877		return false;
2878
2879	/*
2880	 * If use_both_schemes is set, use the first scheme (whichever
2881	 * it is) for the larger half of the retries, then use the other
2882	 * scheme.  Otherwise, use the first scheme for all the retries.
2883	 */
2884	if (use_both_schemes && retry >= (PORT_INIT_TRIES + 1) / 2)
2885		return old_scheme_first_port;	/* Second half */
2886	return !old_scheme_first_port;		/* First half or all */
2887}
2888
2889/* Is a USB 3.0 port in the Inactive or Compliance Mode state?
2890 * Port warm reset is required to recover
2891 */
2892static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
2893		u16 portstatus)
2894{
2895	u16 link_state;
2896
2897	if (!hub_is_superspeed(hub->hdev))
2898		return false;
2899
2900	if (test_bit(port1, hub->warm_reset_bits))
2901		return true;
2902
2903	link_state = portstatus & USB_PORT_STAT_LINK_STATE;
2904	return link_state == USB_SS_PORT_LS_SS_INACTIVE
2905		|| link_state == USB_SS_PORT_LS_COMP_MOD;
2906}
2907
2908static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2909			struct usb_device *udev, unsigned int delay, bool warm)
2910{
2911	int delay_time, ret;
2912	u16 portstatus;
2913	u16 portchange;
2914	u32 ext_portstatus = 0;
2915
2916	for (delay_time = 0;
2917			delay_time < HUB_RESET_TIMEOUT;
2918			delay_time += delay) {
2919		/* wait to give the device a chance to reset */
2920		msleep(delay);
2921
2922		/* read and decode port status */
2923		if (hub_is_superspeedplus(hub->hdev))
2924			ret = hub_ext_port_status(hub, port1,
2925						  HUB_EXT_PORT_STATUS,
2926						  &portstatus, &portchange,
2927						  &ext_portstatus);
2928		else
2929			ret = usb_hub_port_status(hub, port1, &portstatus,
2930					      &portchange);
2931		if (ret < 0)
2932			return ret;
2933
2934		/*
2935		 * The port state is unknown until the reset completes.
2936		 *
2937		 * On top of that, some chips may require additional time
2938		 * to re-establish a connection after the reset is complete,
2939		 * so also wait for the connection to be re-established.
2940		 */
2941		if (!(portstatus & USB_PORT_STAT_RESET) &&
2942		    (portstatus & USB_PORT_STAT_CONNECTION))
2943			break;
2944
2945		/* switch to the long delay after two short delay failures */
2946		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2947			delay = HUB_LONG_RESET_TIME;
2948
2949		dev_dbg(&hub->ports[port1 - 1]->dev,
2950				"not %sreset yet, waiting %dms\n",
2951				warm ? "warm " : "", delay);
2952	}
2953
2954	if ((portstatus & USB_PORT_STAT_RESET))
2955		return -EBUSY;
2956
2957	if (hub_port_warm_reset_required(hub, port1, portstatus))
2958		return -ENOTCONN;
2959
2960	/* Device went away? */
2961	if (!(portstatus & USB_PORT_STAT_CONNECTION))
2962		return -ENOTCONN;
2963
2964	/* Retry if connect change is set but status is still connected.
2965	 * A USB 3.0 connection may bounce if multiple warm resets were issued,
2966	 * but the device may have successfully re-connected. Ignore it.
2967	 */
2968	if (!hub_is_superspeed(hub->hdev) &&
2969	    (portchange & USB_PORT_STAT_C_CONNECTION)) {
2970		usb_clear_port_feature(hub->hdev, port1,
2971				       USB_PORT_FEAT_C_CONNECTION);
2972		return -EAGAIN;
2973	}
2974
2975	if (!(portstatus & USB_PORT_STAT_ENABLE))
2976		return -EBUSY;
2977
2978	if (!udev)
2979		return 0;
2980
2981	if (hub_is_superspeedplus(hub->hdev)) {
2982		/* extended portstatus Rx and Tx lane count are zero based */
2983		udev->rx_lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2984		udev->tx_lanes = USB_EXT_PORT_TX_LANES(ext_portstatus) + 1;
2985		udev->ssp_rate = get_port_ssp_rate(hub->hdev, ext_portstatus);
2986	} else {
2987		udev->rx_lanes = 1;
2988		udev->tx_lanes = 1;
2989		udev->ssp_rate = USB_SSP_GEN_UNKNOWN;
2990	}
2991	if (udev->ssp_rate != USB_SSP_GEN_UNKNOWN)
 
 
2992		udev->speed = USB_SPEED_SUPER_PLUS;
2993	else if (hub_is_superspeed(hub->hdev))
2994		udev->speed = USB_SPEED_SUPER;
2995	else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2996		udev->speed = USB_SPEED_HIGH;
2997	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2998		udev->speed = USB_SPEED_LOW;
2999	else
3000		udev->speed = USB_SPEED_FULL;
3001	return 0;
3002}
3003
3004/* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
3005static int hub_port_reset(struct usb_hub *hub, int port1,
3006			struct usb_device *udev, unsigned int delay, bool warm)
3007{
3008	int i, status;
3009	u16 portchange, portstatus;
3010	struct usb_port *port_dev = hub->ports[port1 - 1];
3011	int reset_recovery_time;
3012
3013	if (!hub_is_superspeed(hub->hdev)) {
3014		if (warm) {
3015			dev_err(hub->intfdev, "only USB3 hub support "
3016						"warm reset\n");
3017			return -EINVAL;
3018		}
3019		/* Block EHCI CF initialization during the port reset.
3020		 * Some companion controllers don't like it when they mix.
3021		 */
3022		down_read(&ehci_cf_port_reset_rwsem);
3023	} else if (!warm) {
3024		/*
3025		 * If the caller hasn't explicitly requested a warm reset,
3026		 * double check and see if one is needed.
3027		 */
3028		if (usb_hub_port_status(hub, port1, &portstatus,
3029					&portchange) == 0)
3030			if (hub_port_warm_reset_required(hub, port1,
3031							portstatus))
3032				warm = true;
3033	}
3034	clear_bit(port1, hub->warm_reset_bits);
3035
3036	/* Reset the port */
3037	for (i = 0; i < PORT_RESET_TRIES; i++) {
3038		status = set_port_feature(hub->hdev, port1, (warm ?
3039					USB_PORT_FEAT_BH_PORT_RESET :
3040					USB_PORT_FEAT_RESET));
3041		if (status == -ENODEV) {
3042			;	/* The hub is gone */
3043		} else if (status) {
3044			dev_err(&port_dev->dev,
3045					"cannot %sreset (err = %d)\n",
3046					warm ? "warm " : "", status);
3047		} else {
3048			status = hub_port_wait_reset(hub, port1, udev, delay,
3049								warm);
3050			if (status && status != -ENOTCONN && status != -ENODEV)
3051				dev_dbg(hub->intfdev,
3052						"port_wait_reset: err = %d\n",
3053						status);
3054		}
3055
3056		/*
3057		 * Check for disconnect or reset, and bail out after several
3058		 * reset attempts to avoid warm reset loop.
3059		 */
3060		if (status == 0 || status == -ENOTCONN || status == -ENODEV ||
3061		    (status == -EBUSY && i == PORT_RESET_TRIES - 1)) {
3062			usb_clear_port_feature(hub->hdev, port1,
3063					USB_PORT_FEAT_C_RESET);
3064
3065			if (!hub_is_superspeed(hub->hdev))
3066				goto done;
3067
3068			usb_clear_port_feature(hub->hdev, port1,
3069					USB_PORT_FEAT_C_BH_PORT_RESET);
3070			usb_clear_port_feature(hub->hdev, port1,
3071					USB_PORT_FEAT_C_PORT_LINK_STATE);
3072
3073			if (udev)
3074				usb_clear_port_feature(hub->hdev, port1,
3075					USB_PORT_FEAT_C_CONNECTION);
3076
3077			/*
3078			 * If a USB 3.0 device migrates from reset to an error
3079			 * state, re-issue the warm reset.
3080			 */
3081			if (usb_hub_port_status(hub, port1,
3082					&portstatus, &portchange) < 0)
3083				goto done;
3084
3085			if (!hub_port_warm_reset_required(hub, port1,
3086					portstatus))
3087				goto done;
3088
3089			/*
3090			 * If the port is in SS.Inactive or Compliance Mode, the
3091			 * hot or warm reset failed.  Try another warm reset.
3092			 */
3093			if (!warm) {
3094				dev_dbg(&port_dev->dev,
3095						"hot reset failed, warm reset\n");
3096				warm = true;
3097			}
3098		}
3099
3100		dev_dbg(&port_dev->dev,
3101				"not enabled, trying %sreset again...\n",
3102				warm ? "warm " : "");
3103		delay = HUB_LONG_RESET_TIME;
3104	}
3105
3106	dev_err(&port_dev->dev, "Cannot enable. Maybe the USB cable is bad?\n");
3107
3108done:
3109	if (status == 0) {
3110		if (port_dev->quirks & USB_PORT_QUIRK_FAST_ENUM)
3111			usleep_range(10000, 12000);
3112		else {
3113			/* TRSTRCY = 10 ms; plus some extra */
3114			reset_recovery_time = 10 + 40;
3115
3116			/* Hub needs extra delay after resetting its port. */
3117			if (hub->hdev->quirks & USB_QUIRK_HUB_SLOW_RESET)
3118				reset_recovery_time += 100;
3119
3120			msleep(reset_recovery_time);
3121		}
3122
3123		if (udev) {
3124			struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3125
3126			update_devnum(udev, 0);
3127			/* The xHC may think the device is already reset,
3128			 * so ignore the status.
3129			 */
3130			if (hcd->driver->reset_device)
3131				hcd->driver->reset_device(hcd, udev);
3132
3133			usb_set_device_state(udev, USB_STATE_DEFAULT);
3134		}
3135	} else {
3136		if (udev)
3137			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
3138	}
3139
3140	if (!hub_is_superspeed(hub->hdev))
3141		up_read(&ehci_cf_port_reset_rwsem);
3142
3143	return status;
3144}
3145
3146/*
3147 * hub_port_stop_enumerate - stop USB enumeration or ignore port events
3148 * @hub: target hub
3149 * @port1: port num of the port
3150 * @retries: port retries number of hub_port_init()
3151 *
3152 * Return:
3153 *    true: ignore port actions/events or give up connection attempts.
3154 *    false: keep original behavior.
3155 *
3156 * This function will be based on retries to check whether the port which is
3157 * marked with early_stop attribute would stop enumeration or ignore events.
3158 *
3159 * Note:
3160 * This function didn't change anything if early_stop is not set, and it will
3161 * prevent all connection attempts when early_stop is set and the attempts of
3162 * the port are more than 1.
3163 */
3164static bool hub_port_stop_enumerate(struct usb_hub *hub, int port1, int retries)
3165{
3166	struct usb_port *port_dev = hub->ports[port1 - 1];
3167
3168	if (port_dev->early_stop) {
3169		if (port_dev->ignore_event)
3170			return true;
3171
3172		/*
3173		 * We want unsuccessful attempts to fail quickly.
3174		 * Since some devices may need one failure during
3175		 * port initialization, we allow two tries but no
3176		 * more.
3177		 */
3178		if (retries < 2)
3179			return false;
3180
3181		port_dev->ignore_event = 1;
3182	} else
3183		port_dev->ignore_event = 0;
3184
3185	return port_dev->ignore_event;
3186}
3187
3188/* Check if a port is power on */
3189int usb_port_is_power_on(struct usb_hub *hub, unsigned int portstatus)
3190{
3191	int ret = 0;
3192
3193	if (hub_is_superspeed(hub->hdev)) {
3194		if (portstatus & USB_SS_PORT_STAT_POWER)
3195			ret = 1;
3196	} else {
3197		if (portstatus & USB_PORT_STAT_POWER)
3198			ret = 1;
3199	}
3200
3201	return ret;
3202}
3203
3204static void usb_lock_port(struct usb_port *port_dev)
3205		__acquires(&port_dev->status_lock)
3206{
3207	mutex_lock(&port_dev->status_lock);
3208	__acquire(&port_dev->status_lock);
3209}
3210
3211static void usb_unlock_port(struct usb_port *port_dev)
3212		__releases(&port_dev->status_lock)
3213{
3214	mutex_unlock(&port_dev->status_lock);
3215	__release(&port_dev->status_lock);
3216}
3217
3218#ifdef	CONFIG_PM
3219
3220/* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
3221static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
3222{
3223	int ret = 0;
3224
3225	if (hub_is_superspeed(hub->hdev)) {
3226		if ((portstatus & USB_PORT_STAT_LINK_STATE)
3227				== USB_SS_PORT_LS_U3)
3228			ret = 1;
3229	} else {
3230		if (portstatus & USB_PORT_STAT_SUSPEND)
3231			ret = 1;
3232	}
3233
3234	return ret;
3235}
3236
3237/* Determine whether the device on a port is ready for a normal resume,
3238 * is ready for a reset-resume, or should be disconnected.
3239 */
3240static int check_port_resume_type(struct usb_device *udev,
3241		struct usb_hub *hub, int port1,
3242		int status, u16 portchange, u16 portstatus)
3243{
3244	struct usb_port *port_dev = hub->ports[port1 - 1];
3245	int retries = 3;
3246
3247 retry:
3248	/* Is a warm reset needed to recover the connection? */
3249	if (status == 0 && udev->reset_resume
3250		&& hub_port_warm_reset_required(hub, port1, portstatus)) {
3251		/* pass */;
3252	}
3253	/* Is the device still present? */
3254	else if (status || port_is_suspended(hub, portstatus) ||
3255			!usb_port_is_power_on(hub, portstatus)) {
3256		if (status >= 0)
3257			status = -ENODEV;
3258	} else if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
3259		if (retries--) {
3260			usleep_range(200, 300);
3261			status = usb_hub_port_status(hub, port1, &portstatus,
3262							     &portchange);
3263			goto retry;
3264		}
3265		status = -ENODEV;
3266	}
3267
3268	/* Can't do a normal resume if the port isn't enabled,
3269	 * so try a reset-resume instead.
3270	 */
3271	else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
3272		if (udev->persist_enabled)
3273			udev->reset_resume = 1;
3274		else
3275			status = -ENODEV;
3276	}
3277
3278	if (status) {
3279		dev_dbg(&port_dev->dev, "status %04x.%04x after resume, %d\n",
3280				portchange, portstatus, status);
3281	} else if (udev->reset_resume) {
3282
3283		/* Late port handoff can set status-change bits */
3284		if (portchange & USB_PORT_STAT_C_CONNECTION)
3285			usb_clear_port_feature(hub->hdev, port1,
3286					USB_PORT_FEAT_C_CONNECTION);
3287		if (portchange & USB_PORT_STAT_C_ENABLE)
3288			usb_clear_port_feature(hub->hdev, port1,
3289					USB_PORT_FEAT_C_ENABLE);
3290
3291		/*
3292		 * Whatever made this reset-resume necessary may have
3293		 * turned on the port1 bit in hub->change_bits.  But after
3294		 * a successful reset-resume we want the bit to be clear;
3295		 * if it was on it would indicate that something happened
3296		 * following the reset-resume.
3297		 */
3298		clear_bit(port1, hub->change_bits);
3299	}
3300
3301	return status;
3302}
3303
3304int usb_disable_ltm(struct usb_device *udev)
3305{
3306	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3307
3308	/* Check if the roothub and device supports LTM. */
3309	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3310			!usb_device_supports_ltm(udev))
3311		return 0;
3312
3313	/* Clear Feature LTM Enable can only be sent if the device is
3314	 * configured.
3315	 */
3316	if (!udev->actconfig)
3317		return 0;
3318
3319	return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3320			USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3321			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3322			USB_CTRL_SET_TIMEOUT);
3323}
3324EXPORT_SYMBOL_GPL(usb_disable_ltm);
3325
3326void usb_enable_ltm(struct usb_device *udev)
3327{
3328	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3329
3330	/* Check if the roothub and device supports LTM. */
3331	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3332			!usb_device_supports_ltm(udev))
3333		return;
3334
3335	/* Set Feature LTM Enable can only be sent if the device is
3336	 * configured.
3337	 */
3338	if (!udev->actconfig)
3339		return;
3340
3341	usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3342			USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3343			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3344			USB_CTRL_SET_TIMEOUT);
3345}
3346EXPORT_SYMBOL_GPL(usb_enable_ltm);
3347
3348/*
3349 * usb_enable_remote_wakeup - enable remote wakeup for a device
3350 * @udev: target device
3351 *
3352 * For USB-2 devices: Set the device's remote wakeup feature.
3353 *
3354 * For USB-3 devices: Assume there's only one function on the device and
3355 * enable remote wake for the first interface.  FIXME if the interface
3356 * association descriptor shows there's more than one function.
3357 */
3358static int usb_enable_remote_wakeup(struct usb_device *udev)
3359{
3360	if (udev->speed < USB_SPEED_SUPER)
3361		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3362				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3363				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3364				USB_CTRL_SET_TIMEOUT);
3365	else
3366		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3367				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3368				USB_INTRF_FUNC_SUSPEND,
3369				USB_INTRF_FUNC_SUSPEND_RW |
3370					USB_INTRF_FUNC_SUSPEND_LP,
3371				NULL, 0, USB_CTRL_SET_TIMEOUT);
3372}
3373
3374/*
3375 * usb_disable_remote_wakeup - disable remote wakeup for a device
3376 * @udev: target device
3377 *
3378 * For USB-2 devices: Clear the device's remote wakeup feature.
3379 *
3380 * For USB-3 devices: Assume there's only one function on the device and
3381 * disable remote wake for the first interface.  FIXME if the interface
3382 * association descriptor shows there's more than one function.
3383 */
3384static int usb_disable_remote_wakeup(struct usb_device *udev)
3385{
3386	if (udev->speed < USB_SPEED_SUPER)
3387		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3388				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3389				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3390				USB_CTRL_SET_TIMEOUT);
3391	else
3392		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3393				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3394				USB_INTRF_FUNC_SUSPEND,	0, NULL, 0,
3395				USB_CTRL_SET_TIMEOUT);
3396}
3397
3398/* Count of wakeup-enabled devices at or below udev */
3399unsigned usb_wakeup_enabled_descendants(struct usb_device *udev)
3400{
3401	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
3402
3403	return udev->do_remote_wakeup +
3404			(hub ? hub->wakeup_enabled_descendants : 0);
3405}
3406EXPORT_SYMBOL_GPL(usb_wakeup_enabled_descendants);
3407
3408/*
3409 * usb_port_suspend - suspend a usb device's upstream port
3410 * @udev: device that's no longer in active use, not a root hub
3411 * Context: must be able to sleep; device not locked; pm locks held
3412 *
3413 * Suspends a USB device that isn't in active use, conserving power.
3414 * Devices may wake out of a suspend, if anything important happens,
3415 * using the remote wakeup mechanism.  They may also be taken out of
3416 * suspend by the host, using usb_port_resume().  It's also routine
3417 * to disconnect devices while they are suspended.
3418 *
3419 * This only affects the USB hardware for a device; its interfaces
3420 * (and, for hubs, child devices) must already have been suspended.
3421 *
3422 * Selective port suspend reduces power; most suspended devices draw
3423 * less than 500 uA.  It's also used in OTG, along with remote wakeup.
3424 * All devices below the suspended port are also suspended.
3425 *
3426 * Devices leave suspend state when the host wakes them up.  Some devices
3427 * also support "remote wakeup", where the device can activate the USB
3428 * tree above them to deliver data, such as a keypress or packet.  In
3429 * some cases, this wakes the USB host.
3430 *
3431 * Suspending OTG devices may trigger HNP, if that's been enabled
3432 * between a pair of dual-role devices.  That will change roles, such
3433 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
3434 *
3435 * Devices on USB hub ports have only one "suspend" state, corresponding
3436 * to ACPI D2, "may cause the device to lose some context".
3437 * State transitions include:
3438 *
3439 *   - suspend, resume ... when the VBUS power link stays live
3440 *   - suspend, disconnect ... VBUS lost
3441 *
3442 * Once VBUS drop breaks the circuit, the port it's using has to go through
3443 * normal re-enumeration procedures, starting with enabling VBUS power.
3444 * Other than re-initializing the hub (plug/unplug, except for root hubs),
3445 * Linux (2.6) currently has NO mechanisms to initiate that:  no hub_wq
3446 * timer, no SRP, no requests through sysfs.
3447 *
3448 * If Runtime PM isn't enabled or used, non-SuperSpeed devices may not get
3449 * suspended until their bus goes into global suspend (i.e., the root
3450 * hub is suspended).  Nevertheless, we change @udev->state to
3451 * USB_STATE_SUSPENDED as this is the device's "logical" state.  The actual
3452 * upstream port setting is stored in @udev->port_is_suspended.
3453 *
3454 * Returns 0 on success, else negative errno.
3455 */
3456int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
3457{
3458	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3459	struct usb_port *port_dev = hub->ports[udev->portnum - 1];
3460	int		port1 = udev->portnum;
3461	int		status;
3462	bool		really_suspend = true;
3463
3464	usb_lock_port(port_dev);
3465
3466	/* enable remote wakeup when appropriate; this lets the device
3467	 * wake up the upstream hub (including maybe the root hub).
3468	 *
3469	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
3470	 * we don't explicitly enable it here.
3471	 */
3472	if (udev->do_remote_wakeup) {
3473		status = usb_enable_remote_wakeup(udev);
3474		if (status) {
3475			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
3476					status);
3477			/* bail if autosuspend is requested */
3478			if (PMSG_IS_AUTO(msg))
3479				goto err_wakeup;
3480		}
3481	}
3482
3483	/* disable USB2 hardware LPM */
3484	usb_disable_usb2_hardware_lpm(udev);
3485
3486	if (usb_disable_ltm(udev)) {
3487		dev_err(&udev->dev, "Failed to disable LTM before suspend\n");
3488		status = -ENOMEM;
3489		if (PMSG_IS_AUTO(msg))
3490			goto err_ltm;
3491	}
3492
3493	/* see 7.1.7.6 */
3494	if (hub_is_superspeed(hub->hdev))
3495		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U3);
3496
3497	/*
3498	 * For system suspend, we do not need to enable the suspend feature
3499	 * on individual USB-2 ports.  The devices will automatically go
3500	 * into suspend a few ms after the root hub stops sending packets.
3501	 * The USB 2.0 spec calls this "global suspend".
3502	 *
3503	 * However, many USB hubs have a bug: They don't relay wakeup requests
3504	 * from a downstream port if the port's suspend feature isn't on.
3505	 * Therefore we will turn on the suspend feature if udev or any of its
3506	 * descendants is enabled for remote wakeup.
3507	 */
3508	else if (PMSG_IS_AUTO(msg) || usb_wakeup_enabled_descendants(udev) > 0)
3509		status = set_port_feature(hub->hdev, port1,
3510				USB_PORT_FEAT_SUSPEND);
3511	else {
3512		really_suspend = false;
3513		status = 0;
3514	}
3515	if (status) {
3516		/* Check if the port has been suspended for the timeout case
3517		 * to prevent the suspended port from incorrect handling.
3518		 */
3519		if (status == -ETIMEDOUT) {
3520			int ret;
3521			u16 portstatus, portchange;
3522
3523			portstatus = portchange = 0;
3524			ret = usb_hub_port_status(hub, port1, &portstatus,
3525					&portchange);
3526
3527			dev_dbg(&port_dev->dev,
3528				"suspend timeout, status %04x\n", portstatus);
3529
3530			if (ret == 0 && port_is_suspended(hub, portstatus)) {
3531				status = 0;
3532				goto suspend_done;
3533			}
3534		}
3535
3536		dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
3537
3538		/* Try to enable USB3 LTM again */
3539		usb_enable_ltm(udev);
3540 err_ltm:
3541		/* Try to enable USB2 hardware LPM again */
3542		usb_enable_usb2_hardware_lpm(udev);
3543
3544		if (udev->do_remote_wakeup)
3545			(void) usb_disable_remote_wakeup(udev);
3546 err_wakeup:
3547
3548		/* System sleep transitions should never fail */
3549		if (!PMSG_IS_AUTO(msg))
3550			status = 0;
3551	} else {
3552 suspend_done:
3553		dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
3554				(PMSG_IS_AUTO(msg) ? "auto-" : ""),
3555				udev->do_remote_wakeup);
3556		if (really_suspend) {
3557			udev->port_is_suspended = 1;
3558
3559			/* device has up to 10 msec to fully suspend */
3560			msleep(10);
3561		}
3562		usb_set_device_state(udev, USB_STATE_SUSPENDED);
3563	}
3564
3565	if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled
3566			&& test_and_clear_bit(port1, hub->child_usage_bits))
3567		pm_runtime_put_sync(&port_dev->dev);
3568
3569	usb_mark_last_busy(hub->hdev);
3570
3571	usb_unlock_port(port_dev);
3572	return status;
3573}
3574
3575/*
3576 * If the USB "suspend" state is in use (rather than "global suspend"),
3577 * many devices will be individually taken out of suspend state using
3578 * special "resume" signaling.  This routine kicks in shortly after
3579 * hardware resume signaling is finished, either because of selective
3580 * resume (by host) or remote wakeup (by device) ... now see what changed
3581 * in the tree that's rooted at this device.
3582 *
3583 * If @udev->reset_resume is set then the device is reset before the
3584 * status check is done.
3585 */
3586static int finish_port_resume(struct usb_device *udev)
3587{
3588	int	status = 0;
3589	u16	devstatus = 0;
3590
3591	/* caller owns the udev device lock */
3592	dev_dbg(&udev->dev, "%s\n",
3593		udev->reset_resume ? "finish reset-resume" : "finish resume");
3594
3595	/* usb ch9 identifies four variants of SUSPENDED, based on what
3596	 * state the device resumes to.  Linux currently won't see the
3597	 * first two on the host side; they'd be inside hub_port_init()
3598	 * during many timeouts, but hub_wq can't suspend until later.
3599	 */
3600	usb_set_device_state(udev, udev->actconfig
3601			? USB_STATE_CONFIGURED
3602			: USB_STATE_ADDRESS);
3603
3604	/* 10.5.4.5 says not to reset a suspended port if the attached
3605	 * device is enabled for remote wakeup.  Hence the reset
3606	 * operation is carried out here, after the port has been
3607	 * resumed.
3608	 */
3609	if (udev->reset_resume) {
3610		/*
3611		 * If the device morphs or switches modes when it is reset,
3612		 * we don't want to perform a reset-resume.  We'll fail the
3613		 * resume, which will cause a logical disconnect, and then
3614		 * the device will be rediscovered.
3615		 */
3616 retry_reset_resume:
3617		if (udev->quirks & USB_QUIRK_RESET)
3618			status = -ENODEV;
3619		else
3620			status = usb_reset_and_verify_device(udev);
3621	}
3622
3623	/* 10.5.4.5 says be sure devices in the tree are still there.
3624	 * For now let's assume the device didn't go crazy on resume,
3625	 * and device drivers will know about any resume quirks.
3626	 */
3627	if (status == 0) {
3628		devstatus = 0;
3629		status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
3630
3631		/* If a normal resume failed, try doing a reset-resume */
3632		if (status && !udev->reset_resume && udev->persist_enabled) {
3633			dev_dbg(&udev->dev, "retry with reset-resume\n");
3634			udev->reset_resume = 1;
3635			goto retry_reset_resume;
3636		}
3637	}
3638
3639	if (status) {
3640		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
3641				status);
3642	/*
3643	 * There are a few quirky devices which violate the standard
3644	 * by claiming to have remote wakeup enabled after a reset,
3645	 * which crash if the feature is cleared, hence check for
3646	 * udev->reset_resume
3647	 */
3648	} else if (udev->actconfig && !udev->reset_resume) {
3649		if (udev->speed < USB_SPEED_SUPER) {
3650			if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
3651				status = usb_disable_remote_wakeup(udev);
3652		} else {
3653			status = usb_get_std_status(udev, USB_RECIP_INTERFACE, 0,
3654					&devstatus);
3655			if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
3656					| USB_INTRF_STAT_FUNC_RW))
3657				status = usb_disable_remote_wakeup(udev);
3658		}
3659
3660		if (status)
3661			dev_dbg(&udev->dev,
3662				"disable remote wakeup, status %d\n",
3663				status);
3664		status = 0;
3665	}
3666	return status;
3667}
3668
3669/*
3670 * There are some SS USB devices which take longer time for link training.
3671 * XHCI specs 4.19.4 says that when Link training is successful, port
3672 * sets CCS bit to 1. So if SW reads port status before successful link
3673 * training, then it will not find device to be present.
3674 * USB Analyzer log with such buggy devices show that in some cases
3675 * device switch on the RX termination after long delay of host enabling
3676 * the VBUS. In few other cases it has been seen that device fails to
3677 * negotiate link training in first attempt. It has been
3678 * reported till now that few devices take as long as 2000 ms to train
3679 * the link after host enabling its VBUS and termination. Following
3680 * routine implements a 2000 ms timeout for link training. If in a case
3681 * link trains before timeout, loop will exit earlier.
3682 *
3683 * There are also some 2.0 hard drive based devices and 3.0 thumb
3684 * drives that, when plugged into a 2.0 only port, take a long
3685 * time to set CCS after VBUS enable.
3686 *
3687 * FIXME: If a device was connected before suspend, but was removed
3688 * while system was asleep, then the loop in the following routine will
3689 * only exit at timeout.
3690 *
3691 * This routine should only be called when persist is enabled.
3692 */
3693static int wait_for_connected(struct usb_device *udev,
3694		struct usb_hub *hub, int port1,
3695		u16 *portchange, u16 *portstatus)
3696{
3697	int status = 0, delay_ms = 0;
3698
3699	while (delay_ms < 2000) {
3700		if (status || *portstatus & USB_PORT_STAT_CONNECTION)
3701			break;
3702		if (!usb_port_is_power_on(hub, *portstatus)) {
3703			status = -ENODEV;
3704			break;
3705		}
3706		msleep(20);
3707		delay_ms += 20;
3708		status = usb_hub_port_status(hub, port1, portstatus, portchange);
3709	}
3710	dev_dbg(&udev->dev, "Waited %dms for CONNECT\n", delay_ms);
3711	return status;
3712}
3713
3714/*
3715 * usb_port_resume - re-activate a suspended usb device's upstream port
3716 * @udev: device to re-activate, not a root hub
3717 * Context: must be able to sleep; device not locked; pm locks held
3718 *
3719 * This will re-activate the suspended device, increasing power usage
3720 * while letting drivers communicate again with its endpoints.
3721 * USB resume explicitly guarantees that the power session between
3722 * the host and the device is the same as it was when the device
3723 * suspended.
3724 *
3725 * If @udev->reset_resume is set then this routine won't check that the
3726 * port is still enabled.  Furthermore, finish_port_resume() above will
3727 * reset @udev.  The end result is that a broken power session can be
3728 * recovered and @udev will appear to persist across a loss of VBUS power.
3729 *
3730 * For example, if a host controller doesn't maintain VBUS suspend current
3731 * during a system sleep or is reset when the system wakes up, all the USB
3732 * power sessions below it will be broken.  This is especially troublesome
3733 * for mass-storage devices containing mounted filesystems, since the
3734 * device will appear to have disconnected and all the memory mappings
3735 * to it will be lost.  Using the USB_PERSIST facility, the device can be
3736 * made to appear as if it had not disconnected.
3737 *
3738 * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
3739 * every effort to insure that the same device is present after the
3740 * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
3741 * quite possible for a device to remain unaltered but its media to be
3742 * changed.  If the user replaces a flash memory card while the system is
3743 * asleep, he will have only himself to blame when the filesystem on the
3744 * new card is corrupted and the system crashes.
3745 *
3746 * Returns 0 on success, else negative errno.
3747 */
3748int usb_port_resume(struct usb_device *udev, pm_message_t msg)
3749{
3750	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3751	struct usb_port *port_dev = hub->ports[udev->portnum  - 1];
3752	int		port1 = udev->portnum;
3753	int		status;
3754	u16		portchange, portstatus;
3755
3756	if (!test_and_set_bit(port1, hub->child_usage_bits)) {
3757		status = pm_runtime_resume_and_get(&port_dev->dev);
3758		if (status < 0) {
3759			dev_dbg(&udev->dev, "can't resume usb port, status %d\n",
3760					status);
3761			return status;
3762		}
3763	}
3764
3765	usb_lock_port(port_dev);
3766
3767	/* Skip the initial Clear-Suspend step for a remote wakeup */
3768	status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3769	if (status == 0 && !port_is_suspended(hub, portstatus)) {
3770		if (portchange & USB_PORT_STAT_C_SUSPEND)
3771			pm_wakeup_event(&udev->dev, 0);
3772		goto SuspendCleared;
3773	}
3774
3775	/* see 7.1.7.7; affects power usage, but not budgeting */
3776	if (hub_is_superspeed(hub->hdev))
3777		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U0);
3778	else
3779		status = usb_clear_port_feature(hub->hdev,
3780				port1, USB_PORT_FEAT_SUSPEND);
3781	if (status) {
3782		dev_dbg(&port_dev->dev, "can't resume, status %d\n", status);
3783	} else {
3784		/* drive resume for USB_RESUME_TIMEOUT msec */
3785		dev_dbg(&udev->dev, "usb %sresume\n",
3786				(PMSG_IS_AUTO(msg) ? "auto-" : ""));
3787		msleep(USB_RESUME_TIMEOUT);
3788
3789		/* Virtual root hubs can trigger on GET_PORT_STATUS to
3790		 * stop resume signaling.  Then finish the resume
3791		 * sequence.
3792		 */
3793		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3794	}
3795
3796 SuspendCleared:
3797	if (status == 0) {
3798		udev->port_is_suspended = 0;
3799		if (hub_is_superspeed(hub->hdev)) {
3800			if (portchange & USB_PORT_STAT_C_LINK_STATE)
3801				usb_clear_port_feature(hub->hdev, port1,
3802					USB_PORT_FEAT_C_PORT_LINK_STATE);
3803		} else {
3804			if (portchange & USB_PORT_STAT_C_SUSPEND)
3805				usb_clear_port_feature(hub->hdev, port1,
3806						USB_PORT_FEAT_C_SUSPEND);
3807		}
3808
3809		/* TRSMRCY = 10 msec */
3810		msleep(10);
3811	}
3812
3813	if (udev->persist_enabled)
3814		status = wait_for_connected(udev, hub, port1, &portchange,
3815				&portstatus);
3816
3817	status = check_port_resume_type(udev,
3818			hub, port1, status, portchange, portstatus);
3819	if (status == 0)
3820		status = finish_port_resume(udev);
3821	if (status < 0) {
3822		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
3823		hub_port_logical_disconnect(hub, port1);
3824	} else  {
3825		/* Try to enable USB2 hardware LPM */
3826		usb_enable_usb2_hardware_lpm(udev);
3827
3828		/* Try to enable USB3 LTM */
3829		usb_enable_ltm(udev);
3830	}
3831
3832	usb_unlock_port(port_dev);
3833
3834	return status;
3835}
3836
3837int usb_remote_wakeup(struct usb_device *udev)
3838{
3839	int	status = 0;
3840
3841	usb_lock_device(udev);
3842	if (udev->state == USB_STATE_SUSPENDED) {
3843		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
3844		status = usb_autoresume_device(udev);
3845		if (status == 0) {
3846			/* Let the drivers do their thing, then... */
3847			usb_autosuspend_device(udev);
3848		}
3849	}
3850	usb_unlock_device(udev);
3851	return status;
3852}
3853
3854/* Returns 1 if there was a remote wakeup and a connect status change. */
3855static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
3856		u16 portstatus, u16 portchange)
3857		__must_hold(&port_dev->status_lock)
3858{
3859	struct usb_port *port_dev = hub->ports[port - 1];
3860	struct usb_device *hdev;
3861	struct usb_device *udev;
3862	int connect_change = 0;
3863	u16 link_state;
3864	int ret;
3865
3866	hdev = hub->hdev;
3867	udev = port_dev->child;
3868	if (!hub_is_superspeed(hdev)) {
3869		if (!(portchange & USB_PORT_STAT_C_SUSPEND))
3870			return 0;
3871		usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
3872	} else {
3873		link_state = portstatus & USB_PORT_STAT_LINK_STATE;
3874		if (!udev || udev->state != USB_STATE_SUSPENDED ||
3875				(link_state != USB_SS_PORT_LS_U0 &&
3876				 link_state != USB_SS_PORT_LS_U1 &&
3877				 link_state != USB_SS_PORT_LS_U2))
3878			return 0;
3879	}
3880
3881	if (udev) {
3882		/* TRSMRCY = 10 msec */
3883		msleep(10);
3884
3885		usb_unlock_port(port_dev);
3886		ret = usb_remote_wakeup(udev);
3887		usb_lock_port(port_dev);
3888		if (ret < 0)
3889			connect_change = 1;
3890	} else {
3891		ret = -ENODEV;
3892		hub_port_disable(hub, port, 1);
3893	}
3894	dev_dbg(&port_dev->dev, "resume, status %d\n", ret);
3895	return connect_change;
3896}
3897
3898static int check_ports_changed(struct usb_hub *hub)
3899{
3900	int port1;
3901
3902	for (port1 = 1; port1 <= hub->hdev->maxchild; ++port1) {
3903		u16 portstatus, portchange;
3904		int status;
3905
3906		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3907		if (!status && portchange)
3908			return 1;
3909	}
3910	return 0;
3911}
3912
3913static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
3914{
3915	struct usb_hub		*hub = usb_get_intfdata(intf);
3916	struct usb_device	*hdev = hub->hdev;
3917	unsigned		port1;
3918
3919	/*
3920	 * Warn if children aren't already suspended.
3921	 * Also, add up the number of wakeup-enabled descendants.
3922	 */
3923	hub->wakeup_enabled_descendants = 0;
3924	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3925		struct usb_port *port_dev = hub->ports[port1 - 1];
3926		struct usb_device *udev = port_dev->child;
3927
3928		if (udev && udev->can_submit) {
3929			dev_warn(&port_dev->dev, "device %s not suspended yet\n",
3930					dev_name(&udev->dev));
3931			if (PMSG_IS_AUTO(msg))
3932				return -EBUSY;
3933		}
3934		if (udev)
3935			hub->wakeup_enabled_descendants +=
3936					usb_wakeup_enabled_descendants(udev);
3937	}
3938
3939	if (hdev->do_remote_wakeup && hub->quirk_check_port_auto_suspend) {
3940		/* check if there are changes pending on hub ports */
3941		if (check_ports_changed(hub)) {
3942			if (PMSG_IS_AUTO(msg))
3943				return -EBUSY;
3944			pm_wakeup_event(&hdev->dev, 2000);
3945		}
3946	}
3947
3948	if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
3949		/* Enable hub to send remote wakeup for all ports. */
3950		for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3951			set_port_feature(hdev,
3952					 port1 |
3953					 USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
3954					 USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
3955					 USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
3956					 USB_PORT_FEAT_REMOTE_WAKE_MASK);
3957		}
3958	}
3959
3960	dev_dbg(&intf->dev, "%s\n", __func__);
3961
3962	/* stop hub_wq and related activity */
3963	hub_quiesce(hub, HUB_SUSPEND);
3964	return 0;
3965}
3966
3967/* Report wakeup requests from the ports of a resuming root hub */
3968static void report_wakeup_requests(struct usb_hub *hub)
3969{
3970	struct usb_device	*hdev = hub->hdev;
3971	struct usb_device	*udev;
3972	struct usb_hcd		*hcd;
3973	unsigned long		resuming_ports;
3974	int			i;
3975
3976	if (hdev->parent)
3977		return;		/* Not a root hub */
3978
3979	hcd = bus_to_hcd(hdev->bus);
3980	if (hcd->driver->get_resuming_ports) {
3981
3982		/*
3983		 * The get_resuming_ports() method returns a bitmap (origin 0)
3984		 * of ports which have started wakeup signaling but have not
3985		 * yet finished resuming.  During system resume we will
3986		 * resume all the enabled ports, regardless of any wakeup
3987		 * signals, which means the wakeup requests would be lost.
3988		 * To prevent this, report them to the PM core here.
3989		 */
3990		resuming_ports = hcd->driver->get_resuming_ports(hcd);
3991		for (i = 0; i < hdev->maxchild; ++i) {
3992			if (test_bit(i, &resuming_ports)) {
3993				udev = hub->ports[i]->child;
3994				if (udev)
3995					pm_wakeup_event(&udev->dev, 0);
3996			}
3997		}
3998	}
3999}
4000
4001static int hub_resume(struct usb_interface *intf)
4002{
4003	struct usb_hub *hub = usb_get_intfdata(intf);
4004
4005	dev_dbg(&intf->dev, "%s\n", __func__);
4006	hub_activate(hub, HUB_RESUME);
4007
4008	/*
4009	 * This should be called only for system resume, not runtime resume.
4010	 * We can't tell the difference here, so some wakeup requests will be
4011	 * reported at the wrong time or more than once.  This shouldn't
4012	 * matter much, so long as they do get reported.
4013	 */
4014	report_wakeup_requests(hub);
4015	return 0;
4016}
4017
4018static int hub_reset_resume(struct usb_interface *intf)
4019{
4020	struct usb_hub *hub = usb_get_intfdata(intf);
4021
4022	dev_dbg(&intf->dev, "%s\n", __func__);
4023	hub_activate(hub, HUB_RESET_RESUME);
4024	return 0;
4025}
4026
4027/**
4028 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
4029 * @rhdev: struct usb_device for the root hub
4030 *
4031 * The USB host controller driver calls this function when its root hub
4032 * is resumed and Vbus power has been interrupted or the controller
4033 * has been reset.  The routine marks @rhdev as having lost power.
4034 * When the hub driver is resumed it will take notice and carry out
4035 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
4036 * the others will be disconnected.
4037 */
4038void usb_root_hub_lost_power(struct usb_device *rhdev)
4039{
4040	dev_notice(&rhdev->dev, "root hub lost power or was reset\n");
4041	rhdev->reset_resume = 1;
4042}
4043EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
4044
4045static const char * const usb3_lpm_names[]  = {
4046	"U0",
4047	"U1",
4048	"U2",
4049	"U3",
4050};
4051
4052/*
4053 * Send a Set SEL control transfer to the device, prior to enabling
4054 * device-initiated U1 or U2.  This lets the device know the exit latencies from
4055 * the time the device initiates a U1 or U2 exit, to the time it will receive a
4056 * packet from the host.
4057 *
4058 * This function will fail if the SEL or PEL values for udev are greater than
4059 * the maximum allowed values for the link state to be enabled.
4060 */
4061static int usb_req_set_sel(struct usb_device *udev)
4062{
4063	struct usb_set_sel_req *sel_values;
4064	unsigned long long u1_sel;
4065	unsigned long long u1_pel;
4066	unsigned long long u2_sel;
4067	unsigned long long u2_pel;
4068	int ret;
4069
4070	if (!udev->parent || udev->speed < USB_SPEED_SUPER || !udev->lpm_capable)
4071		return 0;
4072
4073	/* Convert SEL and PEL stored in ns to us */
4074	u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
4075	u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
4076	u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
4077	u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
4078
4079	/*
4080	 * Make sure that the calculated SEL and PEL values for the link
4081	 * state we're enabling aren't bigger than the max SEL/PEL
4082	 * value that will fit in the SET SEL control transfer.
4083	 * Otherwise the device would get an incorrect idea of the exit
4084	 * latency for the link state, and could start a device-initiated
4085	 * U1/U2 when the exit latencies are too high.
4086	 */
4087	if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
4088	    u1_pel > USB3_LPM_MAX_U1_SEL_PEL ||
4089	    u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
4090	    u2_pel > USB3_LPM_MAX_U2_SEL_PEL) {
4091		dev_dbg(&udev->dev, "Device-initiated U1/U2 disabled due to long SEL or PEL\n");
4092		return -EINVAL;
4093	}
4094
4095	/*
4096	 * usb_enable_lpm() can be called as part of a failed device reset,
4097	 * which may be initiated by an error path of a mass storage driver.
4098	 * Therefore, use GFP_NOIO.
4099	 */
4100	sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
4101	if (!sel_values)
4102		return -ENOMEM;
4103
4104	sel_values->u1_sel = u1_sel;
4105	sel_values->u1_pel = u1_pel;
4106	sel_values->u2_sel = cpu_to_le16(u2_sel);
4107	sel_values->u2_pel = cpu_to_le16(u2_pel);
4108
4109	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4110			USB_REQ_SET_SEL,
4111			USB_RECIP_DEVICE,
4112			0, 0,
4113			sel_values, sizeof *(sel_values),
4114			USB_CTRL_SET_TIMEOUT);
4115	kfree(sel_values);
4116
4117	if (ret > 0)
4118		udev->lpm_devinit_allow = 1;
4119
4120	return ret;
4121}
4122
4123/*
4124 * Enable or disable device-initiated U1 or U2 transitions.
4125 */
4126static int usb_set_device_initiated_lpm(struct usb_device *udev,
4127		enum usb3_link_state state, bool enable)
4128{
4129	int ret;
4130	int feature;
4131
4132	switch (state) {
4133	case USB3_LPM_U1:
4134		feature = USB_DEVICE_U1_ENABLE;
4135		break;
4136	case USB3_LPM_U2:
4137		feature = USB_DEVICE_U2_ENABLE;
4138		break;
4139	default:
4140		dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
4141				__func__, enable ? "enable" : "disable");
4142		return -EINVAL;
4143	}
4144
4145	if (udev->state != USB_STATE_CONFIGURED) {
4146		dev_dbg(&udev->dev, "%s: Can't %s %s state "
4147				"for unconfigured device.\n",
4148				__func__, enable ? "enable" : "disable",
4149				usb3_lpm_names[state]);
4150		return 0;
4151	}
4152
4153	if (enable) {
4154		/*
4155		 * Now send the control transfer to enable device-initiated LPM
4156		 * for either U1 or U2.
4157		 */
4158		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4159				USB_REQ_SET_FEATURE,
4160				USB_RECIP_DEVICE,
4161				feature,
4162				0, NULL, 0,
4163				USB_CTRL_SET_TIMEOUT);
4164	} else {
4165		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4166				USB_REQ_CLEAR_FEATURE,
4167				USB_RECIP_DEVICE,
4168				feature,
4169				0, NULL, 0,
4170				USB_CTRL_SET_TIMEOUT);
4171	}
4172	if (ret < 0) {
4173		dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
4174				enable ? "Enable" : "Disable",
4175				usb3_lpm_names[state]);
4176		return -EBUSY;
4177	}
4178	return 0;
4179}
4180
4181static int usb_set_lpm_timeout(struct usb_device *udev,
4182		enum usb3_link_state state, int timeout)
4183{
4184	int ret;
4185	int feature;
4186
4187	switch (state) {
4188	case USB3_LPM_U1:
4189		feature = USB_PORT_FEAT_U1_TIMEOUT;
4190		break;
4191	case USB3_LPM_U2:
4192		feature = USB_PORT_FEAT_U2_TIMEOUT;
4193		break;
4194	default:
4195		dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
4196				__func__);
4197		return -EINVAL;
4198	}
4199
4200	if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
4201			timeout != USB3_LPM_DEVICE_INITIATED) {
4202		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
4203				"which is a reserved value.\n",
4204				usb3_lpm_names[state], timeout);
4205		return -EINVAL;
4206	}
4207
4208	ret = set_port_feature(udev->parent,
4209			USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
4210			feature);
4211	if (ret < 0) {
4212		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
4213				"error code %i\n", usb3_lpm_names[state],
4214				timeout, ret);
4215		return -EBUSY;
4216	}
4217	if (state == USB3_LPM_U1)
4218		udev->u1_params.timeout = timeout;
4219	else
4220		udev->u2_params.timeout = timeout;
4221	return 0;
4222}
4223
4224/*
4225 * Don't allow device intiated U1/U2 if the system exit latency + one bus
4226 * interval is greater than the minimum service interval of any active
4227 * periodic endpoint. See USB 3.2 section 9.4.9
4228 */
4229static bool usb_device_may_initiate_lpm(struct usb_device *udev,
4230					enum usb3_link_state state)
4231{
4232	unsigned int sel;		/* us */
4233	int i, j;
4234
4235	if (!udev->lpm_devinit_allow)
4236		return false;
4237
4238	if (state == USB3_LPM_U1)
4239		sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
4240	else if (state == USB3_LPM_U2)
4241		sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
4242	else
4243		return false;
4244
4245	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
4246		struct usb_interface *intf;
4247		struct usb_endpoint_descriptor *desc;
4248		unsigned int interval;
4249
4250		intf = udev->actconfig->interface[i];
4251		if (!intf)
4252			continue;
4253
4254		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++) {
4255			desc = &intf->cur_altsetting->endpoint[j].desc;
4256
4257			if (usb_endpoint_xfer_int(desc) ||
4258			    usb_endpoint_xfer_isoc(desc)) {
4259				interval = (1 << (desc->bInterval - 1)) * 125;
4260				if (sel + 125 > interval)
4261					return false;
4262			}
4263		}
4264	}
4265	return true;
4266}
4267
4268/*
4269 * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
4270 * U1/U2 entry.
4271 *
4272 * We will attempt to enable U1 or U2, but there are no guarantees that the
4273 * control transfers to set the hub timeout or enable device-initiated U1/U2
4274 * will be successful.
4275 *
4276 * If the control transfer to enable device-initiated U1/U2 entry fails, then
4277 * hub-initiated U1/U2 will be disabled.
4278 *
4279 * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
4280 * driver know about it.  If that call fails, it should be harmless, and just
4281 * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
4282 */
4283static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4284		enum usb3_link_state state)
4285{
4286	int timeout;
4287	__u8 u1_mel;
4288	__le16 u2_mel;
4289
4290	/* Skip if the device BOS descriptor couldn't be read */
4291	if (!udev->bos)
4292		return;
4293
4294	u1_mel = udev->bos->ss_cap->bU1devExitLat;
4295	u2_mel = udev->bos->ss_cap->bU2DevExitLat;
4296
4297	/* If the device says it doesn't have *any* exit latency to come out of
4298	 * U1 or U2, it's probably lying.  Assume it doesn't implement that link
4299	 * state.
4300	 */
4301	if ((state == USB3_LPM_U1 && u1_mel == 0) ||
4302			(state == USB3_LPM_U2 && u2_mel == 0))
4303		return;
4304
4305	/* We allow the host controller to set the U1/U2 timeout internally
4306	 * first, so that it can change its schedule to account for the
4307	 * additional latency to send data to a device in a lower power
4308	 * link state.
4309	 */
4310	timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);
4311
4312	/* xHCI host controller doesn't want to enable this LPM state. */
4313	if (timeout == 0)
4314		return;
4315
4316	if (timeout < 0) {
4317		dev_warn(&udev->dev, "Could not enable %s link state, "
4318				"xHCI error %i.\n", usb3_lpm_names[state],
4319				timeout);
4320		return;
4321	}
4322
4323	if (usb_set_lpm_timeout(udev, state, timeout)) {
4324		/* If we can't set the parent hub U1/U2 timeout,
4325		 * device-initiated LPM won't be allowed either, so let the xHCI
4326		 * host know that this link state won't be enabled.
4327		 */
4328		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4329		return;
4330	}
4331
4332	/* Only a configured device will accept the Set Feature
4333	 * U1/U2_ENABLE
4334	 */
4335	if (udev->actconfig &&
4336	    usb_device_may_initiate_lpm(udev, state)) {
4337		if (usb_set_device_initiated_lpm(udev, state, true)) {
4338			/*
4339			 * Request to enable device initiated U1/U2 failed,
4340			 * better to turn off lpm in this case.
4341			 */
4342			usb_set_lpm_timeout(udev, state, 0);
4343			hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4344			return;
4345		}
4346	}
4347
4348	if (state == USB3_LPM_U1)
4349		udev->usb3_lpm_u1_enabled = 1;
4350	else if (state == USB3_LPM_U2)
4351		udev->usb3_lpm_u2_enabled = 1;
4352}
4353/*
4354 * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
4355 * U1/U2 entry.
4356 *
4357 * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
4358 * If zero is returned, the parent will not allow the link to go into U1/U2.
4359 *
4360 * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
4361 * it won't have an effect on the bus link state because the parent hub will
4362 * still disallow device-initiated U1/U2 entry.
4363 *
4364 * If zero is returned, the xHCI host controller may still think U1/U2 entry is
4365 * possible.  The result will be slightly more bus bandwidth will be taken up
4366 * (to account for U1/U2 exit latency), but it should be harmless.
4367 */
4368static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4369		enum usb3_link_state state)
4370{
4371	switch (state) {
4372	case USB3_LPM_U1:
4373	case USB3_LPM_U2:
4374		break;
4375	default:
4376		dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
4377				__func__);
4378		return -EINVAL;
4379	}
4380
4381	if (usb_set_lpm_timeout(udev, state, 0))
4382		return -EBUSY;
4383
4384	usb_set_device_initiated_lpm(udev, state, false);
4385
4386	if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
4387		dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
4388				"bus schedule bandwidth may be impacted.\n",
4389				usb3_lpm_names[state]);
4390
4391	/* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM
4392	 * is disabled. Hub will disallows link to enter U1/U2 as well,
4393	 * even device is initiating LPM. Hence LPM is disabled if hub LPM
4394	 * timeout set to 0, no matter device-initiated LPM is disabled or
4395	 * not.
4396	 */
4397	if (state == USB3_LPM_U1)
4398		udev->usb3_lpm_u1_enabled = 0;
4399	else if (state == USB3_LPM_U2)
4400		udev->usb3_lpm_u2_enabled = 0;
4401
4402	return 0;
4403}
4404
4405/*
4406 * Disable hub-initiated and device-initiated U1 and U2 entry.
4407 * Caller must own the bandwidth_mutex.
4408 *
4409 * This will call usb_enable_lpm() on failure, which will decrement
4410 * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
4411 */
4412int usb_disable_lpm(struct usb_device *udev)
4413{
4414	struct usb_hcd *hcd;
4415
4416	if (!udev || !udev->parent ||
4417			udev->speed < USB_SPEED_SUPER ||
4418			!udev->lpm_capable ||
4419			udev->state < USB_STATE_CONFIGURED)
4420		return 0;
4421
4422	hcd = bus_to_hcd(udev->bus);
4423	if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
4424		return 0;
4425
4426	udev->lpm_disable_count++;
4427	if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
4428		return 0;
4429
4430	/* If LPM is enabled, attempt to disable it. */
4431	if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
4432		goto enable_lpm;
4433	if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
4434		goto enable_lpm;
4435
4436	return 0;
4437
4438enable_lpm:
4439	usb_enable_lpm(udev);
4440	return -EBUSY;
4441}
4442EXPORT_SYMBOL_GPL(usb_disable_lpm);
4443
4444/* Grab the bandwidth_mutex before calling usb_disable_lpm() */
4445int usb_unlocked_disable_lpm(struct usb_device *udev)
4446{
4447	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4448	int ret;
4449
4450	if (!hcd)
4451		return -EINVAL;
4452
4453	mutex_lock(hcd->bandwidth_mutex);
4454	ret = usb_disable_lpm(udev);
4455	mutex_unlock(hcd->bandwidth_mutex);
4456
4457	return ret;
4458}
4459EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4460
4461/*
4462 * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
4463 * xHCI host policy may prevent U1 or U2 from being enabled.
4464 *
4465 * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
4466 * until the lpm_disable_count drops to zero.  Caller must own the
4467 * bandwidth_mutex.
4468 */
4469void usb_enable_lpm(struct usb_device *udev)
4470{
4471	struct usb_hcd *hcd;
4472	struct usb_hub *hub;
4473	struct usb_port *port_dev;
4474
4475	if (!udev || !udev->parent ||
4476			udev->speed < USB_SPEED_SUPER ||
4477			!udev->lpm_capable ||
4478			udev->state < USB_STATE_CONFIGURED)
4479		return;
4480
4481	udev->lpm_disable_count--;
4482	hcd = bus_to_hcd(udev->bus);
4483	/* Double check that we can both enable and disable LPM.
4484	 * Device must be configured to accept set feature U1/U2 timeout.
4485	 */
4486	if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
4487			!hcd->driver->disable_usb3_lpm_timeout)
4488		return;
4489
4490	if (udev->lpm_disable_count > 0)
4491		return;
4492
4493	hub = usb_hub_to_struct_hub(udev->parent);
4494	if (!hub)
4495		return;
4496
4497	port_dev = hub->ports[udev->portnum - 1];
4498
4499	if (port_dev->usb3_lpm_u1_permit)
4500		usb_enable_link_state(hcd, udev, USB3_LPM_U1);
4501
4502	if (port_dev->usb3_lpm_u2_permit)
4503		usb_enable_link_state(hcd, udev, USB3_LPM_U2);
4504}
4505EXPORT_SYMBOL_GPL(usb_enable_lpm);
4506
4507/* Grab the bandwidth_mutex before calling usb_enable_lpm() */
4508void usb_unlocked_enable_lpm(struct usb_device *udev)
4509{
4510	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4511
4512	if (!hcd)
4513		return;
4514
4515	mutex_lock(hcd->bandwidth_mutex);
4516	usb_enable_lpm(udev);
4517	mutex_unlock(hcd->bandwidth_mutex);
4518}
4519EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4520
4521/* usb3 devices use U3 for disabled, make sure remote wakeup is disabled */
4522static void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4523					  struct usb_port *port_dev)
4524{
4525	struct usb_device *udev = port_dev->child;
4526	int ret;
4527
4528	if (udev && udev->port_is_suspended && udev->do_remote_wakeup) {
4529		ret = hub_set_port_link_state(hub, port_dev->portnum,
4530					      USB_SS_PORT_LS_U0);
4531		if (!ret) {
4532			msleep(USB_RESUME_TIMEOUT);
4533			ret = usb_disable_remote_wakeup(udev);
4534		}
4535		if (ret)
4536			dev_warn(&udev->dev,
4537				 "Port disable: can't disable remote wake\n");
4538		udev->do_remote_wakeup = 0;
4539	}
4540}
4541
4542#else	/* CONFIG_PM */
4543
4544#define hub_suspend		NULL
4545#define hub_resume		NULL
4546#define hub_reset_resume	NULL
4547
4548static inline void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4549						 struct usb_port *port_dev) { }
4550
4551int usb_disable_lpm(struct usb_device *udev)
4552{
4553	return 0;
4554}
4555EXPORT_SYMBOL_GPL(usb_disable_lpm);
4556
4557void usb_enable_lpm(struct usb_device *udev) { }
4558EXPORT_SYMBOL_GPL(usb_enable_lpm);
4559
4560int usb_unlocked_disable_lpm(struct usb_device *udev)
4561{
4562	return 0;
4563}
4564EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4565
4566void usb_unlocked_enable_lpm(struct usb_device *udev) { }
4567EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4568
4569int usb_disable_ltm(struct usb_device *udev)
4570{
4571	return 0;
4572}
4573EXPORT_SYMBOL_GPL(usb_disable_ltm);
4574
4575void usb_enable_ltm(struct usb_device *udev) { }
4576EXPORT_SYMBOL_GPL(usb_enable_ltm);
4577
4578static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
4579		u16 portstatus, u16 portchange)
4580{
4581	return 0;
4582}
4583
4584static int usb_req_set_sel(struct usb_device *udev)
4585{
4586	return 0;
4587}
4588
4589#endif	/* CONFIG_PM */
4590
4591/*
4592 * USB-3 does not have a similar link state as USB-2 that will avoid negotiating
4593 * a connection with a plugged-in cable but will signal the host when the cable
4594 * is unplugged. Disable remote wake and set link state to U3 for USB-3 devices
4595 */
4596static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
4597{
4598	struct usb_port *port_dev = hub->ports[port1 - 1];
4599	struct usb_device *hdev = hub->hdev;
4600	int ret = 0;
4601
4602	if (!hub->error) {
4603		if (hub_is_superspeed(hub->hdev)) {
4604			hub_usb3_port_prepare_disable(hub, port_dev);
4605			ret = hub_set_port_link_state(hub, port_dev->portnum,
4606						      USB_SS_PORT_LS_U3);
4607		} else {
4608			ret = usb_clear_port_feature(hdev, port1,
4609					USB_PORT_FEAT_ENABLE);
4610		}
4611	}
4612	if (port_dev->child && set_state)
4613		usb_set_device_state(port_dev->child, USB_STATE_NOTATTACHED);
4614	if (ret && ret != -ENODEV)
4615		dev_err(&port_dev->dev, "cannot disable (err = %d)\n", ret);
4616	return ret;
4617}
4618
4619/*
4620 * usb_port_disable - disable a usb device's upstream port
4621 * @udev: device to disable
4622 * Context: @udev locked, must be able to sleep.
4623 *
4624 * Disables a USB device that isn't in active use.
4625 */
4626int usb_port_disable(struct usb_device *udev)
4627{
4628	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4629
4630	return hub_port_disable(hub, udev->portnum, 0);
4631}
4632
4633/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
4634 *
4635 * Between connect detection and reset signaling there must be a delay
4636 * of 100ms at least for debounce and power-settling.  The corresponding
4637 * timer shall restart whenever the downstream port detects a disconnect.
4638 *
4639 * Apparently there are some bluetooth and irda-dongles and a number of
4640 * low-speed devices for which this debounce period may last over a second.
4641 * Not covered by the spec - but easy to deal with.
4642 *
4643 * This implementation uses a 1500ms total debounce timeout; if the
4644 * connection isn't stable by then it returns -ETIMEDOUT.  It checks
4645 * every 25ms for transient disconnects.  When the port status has been
4646 * unchanged for 100ms it returns the port status.
4647 */
4648int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
4649{
4650	int ret;
4651	u16 portchange, portstatus;
4652	unsigned connection = 0xffff;
4653	int total_time, stable_time = 0;
4654	struct usb_port *port_dev = hub->ports[port1 - 1];
4655
4656	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
4657		ret = usb_hub_port_status(hub, port1, &portstatus, &portchange);
4658		if (ret < 0)
4659			return ret;
4660
4661		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
4662		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
4663			if (!must_be_connected ||
4664			     (connection == USB_PORT_STAT_CONNECTION))
4665				stable_time += HUB_DEBOUNCE_STEP;
4666			if (stable_time >= HUB_DEBOUNCE_STABLE)
4667				break;
4668		} else {
4669			stable_time = 0;
4670			connection = portstatus & USB_PORT_STAT_CONNECTION;
4671		}
4672
4673		if (portchange & USB_PORT_STAT_C_CONNECTION) {
4674			usb_clear_port_feature(hub->hdev, port1,
4675					USB_PORT_FEAT_C_CONNECTION);
4676		}
4677
4678		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
4679			break;
4680		msleep(HUB_DEBOUNCE_STEP);
4681	}
4682
4683	dev_dbg(&port_dev->dev, "debounce total %dms stable %dms status 0x%x\n",
4684			total_time, stable_time, portstatus);
4685
4686	if (stable_time < HUB_DEBOUNCE_STABLE)
4687		return -ETIMEDOUT;
4688	return portstatus;
4689}
4690
4691void usb_ep0_reinit(struct usb_device *udev)
4692{
4693	usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
4694	usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
4695	usb_enable_endpoint(udev, &udev->ep0, true);
4696}
4697EXPORT_SYMBOL_GPL(usb_ep0_reinit);
4698
4699#define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
4700#define usb_rcvaddr0pipe()	((PIPE_CONTROL << 30) | USB_DIR_IN)
4701
4702static int hub_set_address(struct usb_device *udev, int devnum)
4703{
4704	int retval;
4705	unsigned int timeout_ms = USB_CTRL_SET_TIMEOUT;
4706	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4707	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4708
4709	if (hub->hdev->quirks & USB_QUIRK_SHORT_SET_ADDRESS_REQ_TIMEOUT)
4710		timeout_ms = USB_SHORT_SET_ADDRESS_REQ_TIMEOUT;
4711
4712	/*
4713	 * The host controller will choose the device address,
4714	 * instead of the core having chosen it earlier
4715	 */
4716	if (!hcd->driver->address_device && devnum <= 1)
4717		return -EINVAL;
4718	if (udev->state == USB_STATE_ADDRESS)
4719		return 0;
4720	if (udev->state != USB_STATE_DEFAULT)
4721		return -EINVAL;
4722	if (hcd->driver->address_device)
4723		retval = hcd->driver->address_device(hcd, udev, timeout_ms);
4724	else
4725		retval = usb_control_msg(udev, usb_sndaddr0pipe(),
4726				USB_REQ_SET_ADDRESS, 0, devnum, 0,
4727				NULL, 0, timeout_ms);
4728	if (retval == 0) {
4729		update_devnum(udev, devnum);
4730		/* Device now using proper address. */
4731		usb_set_device_state(udev, USB_STATE_ADDRESS);
4732		usb_ep0_reinit(udev);
4733	}
4734	return retval;
4735}
4736
4737/*
4738 * There are reports of USB 3.0 devices that say they support USB 2.0 Link PM
4739 * when they're plugged into a USB 2.0 port, but they don't work when LPM is
4740 * enabled.
4741 *
4742 * Only enable USB 2.0 Link PM if the port is internal (hardwired), or the
4743 * device says it supports the new USB 2.0 Link PM errata by setting the BESL
4744 * support bit in the BOS descriptor.
4745 */
4746static void hub_set_initial_usb2_lpm_policy(struct usb_device *udev)
4747{
4748	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4749	int connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
4750
4751	if (!udev->usb2_hw_lpm_capable || !udev->bos)
4752		return;
4753
4754	if (hub)
4755		connect_type = hub->ports[udev->portnum - 1]->connect_type;
4756
4757	if ((udev->bos->ext_cap->bmAttributes & cpu_to_le32(USB_BESL_SUPPORT)) ||
4758			connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
4759		udev->usb2_hw_lpm_allowed = 1;
4760		usb_enable_usb2_hardware_lpm(udev);
4761	}
4762}
4763
4764static int hub_enable_device(struct usb_device *udev)
4765{
4766	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4767
4768	if (!hcd->driver->enable_device)
4769		return 0;
4770	if (udev->state == USB_STATE_ADDRESS)
4771		return 0;
4772	if (udev->state != USB_STATE_DEFAULT)
4773		return -EINVAL;
4774
4775	return hcd->driver->enable_device(hcd, udev);
4776}
4777
4778/*
4779 * Get the bMaxPacketSize0 value during initialization by reading the
4780 * device's device descriptor.  Since we don't already know this value,
4781 * the transfer is unsafe and it ignores I/O errors, only testing for
4782 * reasonable received values.
4783 *
4784 * For "old scheme" initialization, size will be 8 so we read just the
4785 * start of the device descriptor, which should work okay regardless of
4786 * the actual bMaxPacketSize0 value.  For "new scheme" initialization,
4787 * size will be 64 (and buf will point to a sufficiently large buffer),
4788 * which might not be kosher according to the USB spec but it's what
4789 * Windows does and what many devices expect.
4790 *
4791 * Returns: bMaxPacketSize0 or a negative error code.
4792 */
4793static int get_bMaxPacketSize0(struct usb_device *udev,
4794		struct usb_device_descriptor *buf, int size, bool first_time)
4795{
4796	int i, rc;
4797
4798	/*
4799	 * Retry on all errors; some devices are flakey.
4800	 * 255 is for WUSB devices, we actually need to use
4801	 * 512 (WUSB1.0[4.8.1]).
4802	 */
4803	for (i = 0; i < GET_MAXPACKET0_TRIES; ++i) {
4804		/* Start with invalid values in case the transfer fails */
4805		buf->bDescriptorType = buf->bMaxPacketSize0 = 0;
4806		rc = usb_control_msg(udev, usb_rcvaddr0pipe(),
4807				USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
4808				USB_DT_DEVICE << 8, 0,
4809				buf, size,
4810				initial_descriptor_timeout);
4811		switch (buf->bMaxPacketSize0) {
4812		case 8: case 16: case 32: case 64: case 9:
4813			if (buf->bDescriptorType == USB_DT_DEVICE) {
4814				rc = buf->bMaxPacketSize0;
4815				break;
4816			}
4817			fallthrough;
4818		default:
4819			if (rc >= 0)
4820				rc = -EPROTO;
4821			break;
4822		}
4823
4824		/*
4825		 * Some devices time out if they are powered on
4826		 * when already connected. They need a second
4827		 * reset, so return early. But only on the first
4828		 * attempt, lest we get into a time-out/reset loop.
4829		 */
4830		if (rc > 0 || (rc == -ETIMEDOUT && first_time &&
4831				udev->speed > USB_SPEED_FULL))
4832			break;
4833	}
4834	return rc;
4835}
4836
4837#define GET_DESCRIPTOR_BUFSIZE	64
4838
4839/* Reset device, (re)assign address, get device descriptor.
4840 * Device connection must be stable, no more debouncing needed.
4841 * Returns device in USB_STATE_ADDRESS, except on error.
4842 *
4843 * If this is called for an already-existing device (as part of
4844 * usb_reset_and_verify_device), the caller must own the device lock and
4845 * the port lock.  For a newly detected device that is not accessible
4846 * through any global pointers, it's not necessary to lock the device,
4847 * but it is still necessary to lock the port.
4848 *
4849 * For a newly detected device, @dev_descr must be NULL.  The device
4850 * descriptor retrieved from the device will then be stored in
4851 * @udev->descriptor.  For an already existing device, @dev_descr
4852 * must be non-NULL.  The device descriptor will be stored there,
4853 * not in @udev->descriptor, because descriptors for registered
4854 * devices are meant to be immutable.
4855 */
4856static int
4857hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
4858		int retry_counter, struct usb_device_descriptor *dev_descr)
4859{
4860	struct usb_device	*hdev = hub->hdev;
4861	struct usb_hcd		*hcd = bus_to_hcd(hdev->bus);
4862	struct usb_port		*port_dev = hub->ports[port1 - 1];
4863	int			retries, operations, retval, i;
4864	unsigned		delay = HUB_SHORT_RESET_TIME;
4865	enum usb_device_speed	oldspeed = udev->speed;
4866	const char		*speed;
4867	int			devnum = udev->devnum;
4868	const char		*driver_name;
4869	bool			do_new_scheme;
4870	const bool		initial = !dev_descr;
4871	int			maxp0;
4872	struct usb_device_descriptor	*buf, *descr;
4873
4874	buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
4875	if (!buf)
4876		return -ENOMEM;
4877
4878	/* root hub ports have a slightly longer reset period
4879	 * (from USB 2.0 spec, section 7.1.7.5)
4880	 */
4881	if (!hdev->parent) {
4882		delay = HUB_ROOT_RESET_TIME;
4883		if (port1 == hdev->bus->otg_port)
4884			hdev->bus->b_hnp_enable = 0;
4885	}
4886
4887	/* Some low speed devices have problems with the quick delay, so */
4888	/*  be a bit pessimistic with those devices. RHbug #23670 */
4889	if (oldspeed == USB_SPEED_LOW)
4890		delay = HUB_LONG_RESET_TIME;
4891
4892	/* Reset the device; full speed may morph to high speed */
4893	/* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
4894	retval = hub_port_reset(hub, port1, udev, delay, false);
4895	if (retval < 0)		/* error or disconnect */
4896		goto fail;
4897	/* success, speed is known */
4898
4899	retval = -ENODEV;
4900
4901	/* Don't allow speed changes at reset, except usb 3.0 to faster */
4902	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed &&
4903	    !(oldspeed == USB_SPEED_SUPER && udev->speed > oldspeed)) {
4904		dev_dbg(&udev->dev, "device reset changed speed!\n");
4905		goto fail;
4906	}
4907	oldspeed = udev->speed;
4908
4909	if (initial) {
4910		/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
4911		 * it's fixed size except for full speed devices.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4912		 */
4913		switch (udev->speed) {
4914		case USB_SPEED_SUPER_PLUS:
4915		case USB_SPEED_SUPER:
4916			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
4917			break;
4918		case USB_SPEED_HIGH:		/* fixed at 64 */
4919			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4920			break;
4921		case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
4922			/* to determine the ep0 maxpacket size, try to read
4923			 * the device descriptor to get bMaxPacketSize0 and
4924			 * then correct our initial guess.
4925			 */
4926			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4927			break;
4928		case USB_SPEED_LOW:		/* fixed at 8 */
4929			udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
4930			break;
4931		default:
4932			goto fail;
4933		}
4934	}
4935
4936	speed = usb_speed_string(udev->speed);
 
 
 
4937
4938	/*
4939	 * The controller driver may be NULL if the controller device
4940	 * is the middle device between platform device and roothub.
4941	 * This middle device may not need a device driver due to
4942	 * all hardware control can be at platform device driver, this
4943	 * platform device is usually a dual-role USB controller device.
4944	 */
4945	if (udev->bus->controller->driver)
4946		driver_name = udev->bus->controller->driver->name;
4947	else
4948		driver_name = udev->bus->sysdev->driver->name;
4949
4950	if (udev->speed < USB_SPEED_SUPER)
4951		dev_info(&udev->dev,
4952				"%s %s USB device number %d using %s\n",
4953				(initial ? "new" : "reset"), speed,
4954				devnum, driver_name);
4955
4956	if (initial) {
4957		/* Set up TT records, if needed  */
4958		if (hdev->tt) {
4959			udev->tt = hdev->tt;
4960			udev->ttport = hdev->ttport;
4961		} else if (udev->speed != USB_SPEED_HIGH
4962				&& hdev->speed == USB_SPEED_HIGH) {
4963			if (!hub->tt.hub) {
4964				dev_err(&udev->dev, "parent hub has no TT\n");
4965				retval = -EINVAL;
4966				goto fail;
4967			}
4968			udev->tt = &hub->tt;
4969			udev->ttport = port1;
4970		}
 
 
4971	}
4972
4973	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
4974	 * Because device hardware and firmware is sometimes buggy in
4975	 * this area, and this is how Linux has done it for ages.
4976	 * Change it cautiously.
4977	 *
4978	 * NOTE:  If use_new_scheme() is true we will start by issuing
4979	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
4980	 * so it may help with some non-standards-compliant devices.
4981	 * Otherwise we start with SET_ADDRESS and then try to read the
4982	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
4983	 * value.
4984	 */
4985	do_new_scheme = use_new_scheme(udev, retry_counter, port_dev);
4986
4987	for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
4988		if (hub_port_stop_enumerate(hub, port1, retries)) {
4989			retval = -ENODEV;
4990			break;
4991		}
4992
4993		if (do_new_scheme) {
 
 
 
4994			retval = hub_enable_device(udev);
4995			if (retval < 0) {
4996				dev_err(&udev->dev,
4997					"hub failed to enable device, error %d\n",
4998					retval);
4999				goto fail;
5000			}
5001
5002			maxp0 = get_bMaxPacketSize0(udev, buf,
5003					GET_DESCRIPTOR_BUFSIZE, retries == 0);
5004			if (maxp0 > 0 && !initial &&
5005					maxp0 != udev->descriptor.bMaxPacketSize0) {
5006				dev_err(&udev->dev, "device reset changed ep0 maxpacket size!\n");
5007				retval = -ENODEV;
5008				goto fail;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5009			}
 
 
 
5010
5011			retval = hub_port_reset(hub, port1, udev, delay, false);
5012			if (retval < 0)		/* error or disconnect */
5013				goto fail;
5014			if (oldspeed != udev->speed) {
5015				dev_dbg(&udev->dev,
5016					"device reset changed speed!\n");
5017				retval = -ENODEV;
5018				goto fail;
5019			}
5020			if (maxp0 < 0) {
5021				if (maxp0 != -ENODEV)
5022					dev_err(&udev->dev, "device descriptor read/64, error %d\n",
5023							maxp0);
5024				retval = maxp0;
5025				continue;
5026			}
5027		}
5028
5029		for (operations = 0; operations < SET_ADDRESS_TRIES; ++operations) {
5030			retval = hub_set_address(udev, devnum);
5031			if (retval >= 0)
5032				break;
5033			msleep(200);
5034		}
5035		if (retval < 0) {
5036			if (retval != -ENODEV)
5037				dev_err(&udev->dev, "device not accepting address %d, error %d\n",
5038						devnum, retval);
5039			goto fail;
5040		}
5041		if (udev->speed >= USB_SPEED_SUPER) {
5042			devnum = udev->devnum;
5043			dev_info(&udev->dev,
5044					"%s SuperSpeed%s%s USB device number %d using %s\n",
5045					(udev->config) ? "reset" : "new",
5046				 (udev->speed == USB_SPEED_SUPER_PLUS) ?
5047						" Plus" : "",
5048				 (udev->ssp_rate == USB_SSP_GEN_2x2) ?
5049						" Gen 2x2" :
5050				 (udev->ssp_rate == USB_SSP_GEN_2x1) ?
5051						" Gen 2x1" :
5052				 (udev->ssp_rate == USB_SSP_GEN_1x2) ?
5053						" Gen 1x2" : "",
5054				 devnum, driver_name);
5055		}
5056
5057		/*
5058		 * cope with hardware quirkiness:
5059		 *  - let SET_ADDRESS settle, some device hardware wants it
5060		 *  - read ep0 maxpacket even for high and low speed,
5061		 */
5062		msleep(10);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5063
5064		if (do_new_scheme)
5065			break;
 
 
 
 
 
 
5066
5067		maxp0 = get_bMaxPacketSize0(udev, buf, 8, retries == 0);
5068		if (maxp0 < 0) {
5069			retval = maxp0;
5070			if (retval != -ENODEV)
5071				dev_err(&udev->dev,
5072					"device descriptor read/8, error %d\n",
5073					retval);
 
 
5074		} else {
5075			u32 delay;
5076
5077			if (!initial && maxp0 != udev->descriptor.bMaxPacketSize0) {
5078				dev_err(&udev->dev, "device reset changed ep0 maxpacket size!\n");
5079				retval = -ENODEV;
5080				goto fail;
5081			}
5082
5083			delay = udev->parent->hub_delay;
5084			udev->hub_delay = min_t(u32, delay,
5085						USB_TP_TRANSMISSION_DELAY_MAX);
5086			retval = usb_set_isoch_delay(udev);
5087			if (retval) {
5088				dev_dbg(&udev->dev,
5089					"Failed set isoch delay, error %d\n",
5090					retval);
5091				retval = 0;
5092			}
5093			break;
5094		}
5095	}
5096	if (retval)
5097		goto fail;
5098
5099	/*
5100	 * Check the ep0 maxpacket guess and correct it if necessary.
5101	 * maxp0 is the value stored in the device descriptor;
5102	 * i is the value it encodes (logarithmic for SuperSpeed or greater).
5103	 */
5104	i = maxp0;
5105	if (udev->speed >= USB_SPEED_SUPER) {
5106		if (maxp0 <= 16)
5107			i = 1 << maxp0;
5108		else
5109			i = 0;		/* Invalid */
 
 
 
5110	}
5111	if (usb_endpoint_maxp(&udev->ep0.desc) == i) {
5112		;	/* Initial ep0 maxpacket guess is right */
5113	} else if (((udev->speed == USB_SPEED_FULL ||
5114				udev->speed == USB_SPEED_HIGH) &&
5115			(i == 8 || i == 16 || i == 32 || i == 64)) ||
5116			(udev->speed >= USB_SPEED_SUPER && i > 0)) {
5117		/* Initial guess is wrong; use the descriptor's value */
 
 
 
 
 
 
5118		if (udev->speed == USB_SPEED_FULL)
5119			dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
5120		else
5121			dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
5122		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
5123		usb_ep0_reinit(udev);
5124	} else {
5125		/* Initial guess is wrong and descriptor's value is invalid */
5126		dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", maxp0);
5127		retval = -EMSGSIZE;
5128		goto fail;
5129	}
5130
5131	descr = usb_get_device_descriptor(udev);
5132	if (IS_ERR(descr)) {
5133		retval = PTR_ERR(descr);
5134		if (retval != -ENODEV)
5135			dev_err(&udev->dev, "device descriptor read/all, error %d\n",
5136					retval);
5137		goto fail;
5138	}
5139	if (initial)
5140		udev->descriptor = *descr;
5141	else
5142		*dev_descr = *descr;
5143	kfree(descr);
5144
5145	/*
5146	 * Some superspeed devices have finished the link training process
5147	 * and attached to a superspeed hub port, but the device descriptor
5148	 * got from those devices show they aren't superspeed devices. Warm
5149	 * reset the port attached by the devices can fix them.
5150	 */
5151	if ((udev->speed >= USB_SPEED_SUPER) &&
5152			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
5153		dev_err(&udev->dev, "got a wrong device descriptor, warm reset device\n");
5154		hub_port_reset(hub, port1, udev, HUB_BH_RESET_TIME, true);
5155		retval = -EINVAL;
5156		goto fail;
5157	}
5158
5159	usb_detect_quirks(udev);
5160
5161	if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
5162		retval = usb_get_bos_descriptor(udev);
5163		if (!retval) {
5164			udev->lpm_capable = usb_device_supports_lpm(udev);
5165			udev->lpm_disable_count = 1;
5166			usb_set_lpm_parameters(udev);
5167			usb_req_set_sel(udev);
5168		}
5169	}
5170
5171	retval = 0;
5172	/* notify HCD that we have a device connected and addressed */
5173	if (hcd->driver->update_device)
5174		hcd->driver->update_device(hcd, udev);
5175	hub_set_initial_usb2_lpm_policy(udev);
5176fail:
5177	if (retval) {
5178		hub_port_disable(hub, port1, 0);
5179		update_devnum(udev, devnum);	/* for disconnect processing */
5180	}
5181	kfree(buf);
5182	return retval;
5183}
5184
5185static void
5186check_highspeed(struct usb_hub *hub, struct usb_device *udev, int port1)
5187{
5188	struct usb_qualifier_descriptor	*qual;
5189	int				status;
5190
5191	if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
5192		return;
5193
5194	qual = kmalloc(sizeof *qual, GFP_KERNEL);
5195	if (qual == NULL)
5196		return;
5197
5198	status = usb_get_descriptor(udev, USB_DT_DEVICE_QUALIFIER, 0,
5199			qual, sizeof *qual);
5200	if (status == sizeof *qual) {
5201		dev_info(&udev->dev, "not running at top speed; "
5202			"connect to a high speed hub\n");
5203		/* hub LEDs are probably harder to miss than syslog */
5204		if (hub->has_indicators) {
5205			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
5206			queue_delayed_work(system_power_efficient_wq,
5207					&hub->leds, 0);
5208		}
5209	}
5210	kfree(qual);
5211}
5212
5213static unsigned
5214hub_power_remaining(struct usb_hub *hub)
5215{
5216	struct usb_device *hdev = hub->hdev;
5217	int remaining;
5218	int port1;
5219
5220	if (!hub->limited_power)
5221		return 0;
5222
5223	remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
5224	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
5225		struct usb_port *port_dev = hub->ports[port1 - 1];
5226		struct usb_device *udev = port_dev->child;
5227		unsigned unit_load;
5228		int delta;
5229
5230		if (!udev)
5231			continue;
5232		if (hub_is_superspeed(udev))
5233			unit_load = 150;
5234		else
5235			unit_load = 100;
5236
5237		/*
5238		 * Unconfigured devices may not use more than one unit load,
5239		 * or 8mA for OTG ports
5240		 */
5241		if (udev->actconfig)
5242			delta = usb_get_max_power(udev, udev->actconfig);
5243		else if (port1 != udev->bus->otg_port || hdev->parent)
5244			delta = unit_load;
5245		else
5246			delta = 8;
5247		if (delta > hub->mA_per_port)
5248			dev_warn(&port_dev->dev, "%dmA is over %umA budget!\n",
5249					delta, hub->mA_per_port);
5250		remaining -= delta;
5251	}
5252	if (remaining < 0) {
5253		dev_warn(hub->intfdev, "%dmA over power budget!\n",
5254			-remaining);
5255		remaining = 0;
5256	}
5257	return remaining;
5258}
5259
5260
5261static int descriptors_changed(struct usb_device *udev,
5262		struct usb_device_descriptor *new_device_descriptor,
5263		struct usb_host_bos *old_bos)
5264{
5265	int		changed = 0;
5266	unsigned	index;
5267	unsigned	serial_len = 0;
5268	unsigned	len;
5269	unsigned	old_length;
5270	int		length;
5271	char		*buf;
5272
5273	if (memcmp(&udev->descriptor, new_device_descriptor,
5274			sizeof(*new_device_descriptor)) != 0)
5275		return 1;
5276
5277	if ((old_bos && !udev->bos) || (!old_bos && udev->bos))
5278		return 1;
5279	if (udev->bos) {
5280		len = le16_to_cpu(udev->bos->desc->wTotalLength);
5281		if (len != le16_to_cpu(old_bos->desc->wTotalLength))
5282			return 1;
5283		if (memcmp(udev->bos->desc, old_bos->desc, len))
5284			return 1;
5285	}
5286
5287	/* Since the idVendor, idProduct, and bcdDevice values in the
5288	 * device descriptor haven't changed, we will assume the
5289	 * Manufacturer and Product strings haven't changed either.
5290	 * But the SerialNumber string could be different (e.g., a
5291	 * different flash card of the same brand).
5292	 */
5293	if (udev->serial)
5294		serial_len = strlen(udev->serial) + 1;
5295
5296	len = serial_len;
5297	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5298		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5299		len = max(len, old_length);
5300	}
5301
5302	buf = kmalloc(len, GFP_NOIO);
5303	if (!buf)
5304		/* assume the worst */
5305		return 1;
5306
5307	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5308		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5309		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
5310				old_length);
5311		if (length != old_length) {
5312			dev_dbg(&udev->dev, "config index %d, error %d\n",
5313					index, length);
5314			changed = 1;
5315			break;
5316		}
5317		if (memcmp(buf, udev->rawdescriptors[index], old_length)
5318				!= 0) {
5319			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
5320				index,
5321				((struct usb_config_descriptor *) buf)->
5322					bConfigurationValue);
5323			changed = 1;
5324			break;
5325		}
5326	}
5327
5328	if (!changed && serial_len) {
5329		length = usb_string(udev, udev->descriptor.iSerialNumber,
5330				buf, serial_len);
5331		if (length + 1 != serial_len) {
5332			dev_dbg(&udev->dev, "serial string error %d\n",
5333					length);
5334			changed = 1;
5335		} else if (memcmp(buf, udev->serial, length) != 0) {
5336			dev_dbg(&udev->dev, "serial string changed\n");
5337			changed = 1;
5338		}
5339	}
5340
5341	kfree(buf);
5342	return changed;
5343}
5344
5345static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
5346		u16 portchange)
5347{
5348	int status = -ENODEV;
5349	int i;
5350	unsigned unit_load;
5351	struct usb_device *hdev = hub->hdev;
5352	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
5353	struct usb_port *port_dev = hub->ports[port1 - 1];
5354	struct usb_device *udev = port_dev->child;
5355	static int unreliable_port = -1;
5356	bool retry_locked;
5357
5358	/* Disconnect any existing devices under this port */
5359	if (udev) {
5360		if (hcd->usb_phy && !hdev->parent)
5361			usb_phy_notify_disconnect(hcd->usb_phy, udev->speed);
5362		usb_disconnect(&port_dev->child);
5363	}
5364
5365	/* We can forget about a "removed" device when there's a physical
5366	 * disconnect or the connect status changes.
5367	 */
5368	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5369			(portchange & USB_PORT_STAT_C_CONNECTION))
5370		clear_bit(port1, hub->removed_bits);
5371
5372	if (portchange & (USB_PORT_STAT_C_CONNECTION |
5373				USB_PORT_STAT_C_ENABLE)) {
5374		status = hub_port_debounce_be_stable(hub, port1);
5375		if (status < 0) {
5376			if (status != -ENODEV &&
5377				port1 != unreliable_port &&
5378				printk_ratelimit())
5379				dev_err(&port_dev->dev, "connect-debounce failed\n");
5380			portstatus &= ~USB_PORT_STAT_CONNECTION;
5381			unreliable_port = port1;
5382		} else {
5383			portstatus = status;
5384		}
5385	}
5386
5387	/* Return now if debouncing failed or nothing is connected or
5388	 * the device was "removed".
5389	 */
5390	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5391			test_bit(port1, hub->removed_bits)) {
5392
5393		/*
5394		 * maybe switch power back on (e.g. root hub was reset)
5395		 * but only if the port isn't owned by someone else.
5396		 */
5397		if (hub_is_port_power_switchable(hub)
5398				&& !usb_port_is_power_on(hub, portstatus)
5399				&& !port_dev->port_owner)
5400			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
5401
5402		if (portstatus & USB_PORT_STAT_ENABLE)
5403			goto done;
5404		return;
5405	}
5406	if (hub_is_superspeed(hub->hdev))
5407		unit_load = 150;
5408	else
5409		unit_load = 100;
5410
5411	status = 0;
5412
5413	for (i = 0; i < PORT_INIT_TRIES; i++) {
5414		if (hub_port_stop_enumerate(hub, port1, i)) {
5415			status = -ENODEV;
5416			break;
5417		}
5418
5419		usb_lock_port(port_dev);
5420		mutex_lock(hcd->address0_mutex);
5421		retry_locked = true;
5422		/* reallocate for each attempt, since references
5423		 * to the previous one can escape in various ways
5424		 */
5425		udev = usb_alloc_dev(hdev, hdev->bus, port1);
5426		if (!udev) {
5427			dev_err(&port_dev->dev,
5428					"couldn't allocate usb_device\n");
5429			mutex_unlock(hcd->address0_mutex);
5430			usb_unlock_port(port_dev);
5431			goto done;
5432		}
5433
5434		usb_set_device_state(udev, USB_STATE_POWERED);
5435		udev->bus_mA = hub->mA_per_port;
5436		udev->level = hdev->level + 1;
 
5437
5438		/* Devices connected to SuperSpeed hubs are USB 3.0 or later */
5439		if (hub_is_superspeed(hub->hdev))
5440			udev->speed = USB_SPEED_SUPER;
5441		else
5442			udev->speed = USB_SPEED_UNKNOWN;
5443
5444		choose_devnum(udev);
5445		if (udev->devnum <= 0) {
5446			status = -ENOTCONN;	/* Don't retry */
5447			goto loop;
5448		}
5449
5450		/* reset (non-USB 3.0 devices) and get descriptor */
5451		status = hub_port_init(hub, udev, port1, i, NULL);
5452		if (status < 0)
5453			goto loop;
5454
5455		mutex_unlock(hcd->address0_mutex);
5456		usb_unlock_port(port_dev);
5457		retry_locked = false;
5458
5459		if (udev->quirks & USB_QUIRK_DELAY_INIT)
5460			msleep(2000);
5461
5462		/* consecutive bus-powered hubs aren't reliable; they can
5463		 * violate the voltage drop budget.  if the new child has
5464		 * a "powered" LED, users should notice we didn't enable it
5465		 * (without reading syslog), even without per-port LEDs
5466		 * on the parent.
5467		 */
5468		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
5469				&& udev->bus_mA <= unit_load) {
5470			u16	devstat;
5471
5472			status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0,
5473					&devstat);
5474			if (status) {
5475				dev_dbg(&udev->dev, "get status %d ?\n", status);
5476				goto loop_disable;
5477			}
5478			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
5479				dev_err(&udev->dev,
5480					"can't connect bus-powered hub "
5481					"to this port\n");
5482				if (hub->has_indicators) {
5483					hub->indicator[port1-1] =
5484						INDICATOR_AMBER_BLINK;
5485					queue_delayed_work(
5486						system_power_efficient_wq,
5487						&hub->leds, 0);
5488				}
5489				status = -ENOTCONN;	/* Don't retry */
5490				goto loop_disable;
5491			}
5492		}
5493
5494		/* check for devices running slower than they could */
5495		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
5496				&& udev->speed == USB_SPEED_FULL
5497				&& highspeed_hubs != 0)
5498			check_highspeed(hub, udev, port1);
5499
5500		/* Store the parent's children[] pointer.  At this point
5501		 * udev becomes globally accessible, although presumably
5502		 * no one will look at it until hdev is unlocked.
5503		 */
5504		status = 0;
5505
5506		mutex_lock(&usb_port_peer_mutex);
5507
5508		/* We mustn't add new devices if the parent hub has
5509		 * been disconnected; we would race with the
5510		 * recursively_mark_NOTATTACHED() routine.
5511		 */
5512		spin_lock_irq(&device_state_lock);
5513		if (hdev->state == USB_STATE_NOTATTACHED)
5514			status = -ENOTCONN;
5515		else
5516			port_dev->child = udev;
5517		spin_unlock_irq(&device_state_lock);
5518		mutex_unlock(&usb_port_peer_mutex);
5519
5520		/* Run it through the hoops (find a driver, etc) */
5521		if (!status) {
5522			status = usb_new_device(udev);
5523			if (status) {
5524				mutex_lock(&usb_port_peer_mutex);
5525				spin_lock_irq(&device_state_lock);
5526				port_dev->child = NULL;
5527				spin_unlock_irq(&device_state_lock);
5528				mutex_unlock(&usb_port_peer_mutex);
5529			} else {
5530				if (hcd->usb_phy && !hdev->parent)
5531					usb_phy_notify_connect(hcd->usb_phy,
5532							udev->speed);
5533			}
5534		}
5535
5536		if (status)
5537			goto loop_disable;
5538
5539		status = hub_power_remaining(hub);
5540		if (status)
5541			dev_dbg(hub->intfdev, "%dmA power budget left\n", status);
5542
5543		return;
5544
5545loop_disable:
5546		hub_port_disable(hub, port1, 1);
5547loop:
5548		usb_ep0_reinit(udev);
5549		release_devnum(udev);
5550		hub_free_dev(udev);
5551		if (retry_locked) {
5552			mutex_unlock(hcd->address0_mutex);
5553			usb_unlock_port(port_dev);
5554		}
5555		usb_put_dev(udev);
5556		if ((status == -ENOTCONN) || (status == -ENOTSUPP))
5557			break;
5558
5559		/* When halfway through our retry count, power-cycle the port */
5560		if (i == (PORT_INIT_TRIES - 1) / 2) {
5561			dev_info(&port_dev->dev, "attempt power cycle\n");
5562			usb_hub_set_port_power(hdev, hub, port1, false);
5563			msleep(2 * hub_power_on_good_delay(hub));
5564			usb_hub_set_port_power(hdev, hub, port1, true);
5565			msleep(hub_power_on_good_delay(hub));
5566		}
5567	}
5568	if (hub->hdev->parent ||
5569			!hcd->driver->port_handed_over ||
5570			!(hcd->driver->port_handed_over)(hcd, port1)) {
5571		if (status != -ENOTCONN && status != -ENODEV)
5572			dev_err(&port_dev->dev,
5573					"unable to enumerate USB device\n");
5574	}
5575
5576done:
5577	hub_port_disable(hub, port1, 1);
5578	if (hcd->driver->relinquish_port && !hub->hdev->parent) {
5579		if (status != -ENOTCONN && status != -ENODEV)
5580			hcd->driver->relinquish_port(hcd, port1);
5581	}
5582}
5583
5584/* Handle physical or logical connection change events.
5585 * This routine is called when:
5586 *	a port connection-change occurs;
5587 *	a port enable-change occurs (often caused by EMI);
5588 *	usb_reset_and_verify_device() encounters changed descriptors (as from
5589 *		a firmware download)
5590 * caller already locked the hub
5591 */
5592static void hub_port_connect_change(struct usb_hub *hub, int port1,
5593					u16 portstatus, u16 portchange)
5594		__must_hold(&port_dev->status_lock)
5595{
5596	struct usb_port *port_dev = hub->ports[port1 - 1];
5597	struct usb_device *udev = port_dev->child;
5598	struct usb_device_descriptor *descr;
5599	int status = -ENODEV;
 
5600
5601	dev_dbg(&port_dev->dev, "status %04x, change %04x, %s\n", portstatus,
5602			portchange, portspeed(hub, portstatus));
5603
5604	if (hub->has_indicators) {
5605		set_port_led(hub, port1, HUB_LED_AUTO);
5606		hub->indicator[port1-1] = INDICATOR_AUTO;
5607	}
5608
5609#ifdef	CONFIG_USB_OTG
5610	/* during HNP, don't repeat the debounce */
5611	if (hub->hdev->bus->is_b_host)
5612		portchange &= ~(USB_PORT_STAT_C_CONNECTION |
5613				USB_PORT_STAT_C_ENABLE);
5614#endif
5615
5616	/* Try to resuscitate an existing device */
5617	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
5618			udev->state != USB_STATE_NOTATTACHED) {
5619		if (portstatus & USB_PORT_STAT_ENABLE) {
5620			/*
5621			 * USB-3 connections are initialized automatically by
5622			 * the hostcontroller hardware. Therefore check for
5623			 * changed device descriptors before resuscitating the
5624			 * device.
5625			 */
5626			descr = usb_get_device_descriptor(udev);
5627			if (IS_ERR(descr)) {
 
 
5628				dev_dbg(&udev->dev,
5629						"can't read device descriptor %ld\n",
5630						PTR_ERR(descr));
5631			} else {
5632				if (descriptors_changed(udev, descr,
5633						udev->bos)) {
5634					dev_dbg(&udev->dev,
5635							"device descriptor has changed\n");
 
 
5636				} else {
5637					status = 0; /* Nothing to do */
5638				}
5639				kfree(descr);
5640			}
5641#ifdef CONFIG_PM
5642		} else if (udev->state == USB_STATE_SUSPENDED &&
5643				udev->persist_enabled) {
5644			/* For a suspended device, treat this as a
5645			 * remote wakeup event.
5646			 */
5647			usb_unlock_port(port_dev);
5648			status = usb_remote_wakeup(udev);
5649			usb_lock_port(port_dev);
5650#endif
5651		} else {
5652			/* Don't resuscitate */;
5653		}
5654	}
5655	clear_bit(port1, hub->change_bits);
5656
5657	/* successfully revalidated the connection */
5658	if (status == 0)
5659		return;
5660
5661	usb_unlock_port(port_dev);
5662	hub_port_connect(hub, port1, portstatus, portchange);
5663	usb_lock_port(port_dev);
5664}
5665
5666/* Handle notifying userspace about hub over-current events */
5667static void port_over_current_notify(struct usb_port *port_dev)
5668{
5669	char *envp[3] = { NULL, NULL, NULL };
5670	struct device *hub_dev;
5671	char *port_dev_path;
5672
5673	sysfs_notify(&port_dev->dev.kobj, NULL, "over_current_count");
5674
5675	hub_dev = port_dev->dev.parent;
5676
5677	if (!hub_dev)
5678		return;
5679
5680	port_dev_path = kobject_get_path(&port_dev->dev.kobj, GFP_KERNEL);
5681	if (!port_dev_path)
5682		return;
5683
5684	envp[0] = kasprintf(GFP_KERNEL, "OVER_CURRENT_PORT=%s", port_dev_path);
5685	if (!envp[0])
5686		goto exit;
5687
5688	envp[1] = kasprintf(GFP_KERNEL, "OVER_CURRENT_COUNT=%u",
5689			port_dev->over_current_count);
5690	if (!envp[1])
5691		goto exit;
5692
5693	kobject_uevent_env(&hub_dev->kobj, KOBJ_CHANGE, envp);
5694
5695exit:
5696	kfree(envp[1]);
5697	kfree(envp[0]);
5698	kfree(port_dev_path);
5699}
5700
5701static void port_event(struct usb_hub *hub, int port1)
5702		__must_hold(&port_dev->status_lock)
5703{
5704	int connect_change;
5705	struct usb_port *port_dev = hub->ports[port1 - 1];
5706	struct usb_device *udev = port_dev->child;
5707	struct usb_device *hdev = hub->hdev;
5708	u16 portstatus, portchange;
5709	int i = 0;
5710
5711	connect_change = test_bit(port1, hub->change_bits);
5712	clear_bit(port1, hub->event_bits);
5713	clear_bit(port1, hub->wakeup_bits);
5714
5715	if (usb_hub_port_status(hub, port1, &portstatus, &portchange) < 0)
5716		return;
5717
5718	if (portchange & USB_PORT_STAT_C_CONNECTION) {
5719		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
5720		connect_change = 1;
5721	}
5722
5723	if (portchange & USB_PORT_STAT_C_ENABLE) {
5724		if (!connect_change)
5725			dev_dbg(&port_dev->dev, "enable change, status %08x\n",
5726					portstatus);
5727		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
5728
5729		/*
5730		 * EM interference sometimes causes badly shielded USB devices
5731		 * to be shutdown by the hub, this hack enables them again.
5732		 * Works at least with mouse driver.
5733		 */
5734		if (!(portstatus & USB_PORT_STAT_ENABLE)
5735		    && !connect_change && udev) {
5736			dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
5737			connect_change = 1;
5738		}
5739	}
5740
5741	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
5742		u16 status = 0, unused;
5743		port_dev->over_current_count++;
5744		port_over_current_notify(port_dev);
5745
5746		dev_dbg(&port_dev->dev, "over-current change #%u\n",
5747			port_dev->over_current_count);
5748		usb_clear_port_feature(hdev, port1,
5749				USB_PORT_FEAT_C_OVER_CURRENT);
5750		msleep(100);	/* Cool down */
5751		hub_power_on(hub, true);
5752		usb_hub_port_status(hub, port1, &status, &unused);
5753		if (status & USB_PORT_STAT_OVERCURRENT)
5754			dev_err(&port_dev->dev, "over-current condition\n");
5755	}
5756
5757	if (portchange & USB_PORT_STAT_C_RESET) {
5758		dev_dbg(&port_dev->dev, "reset change\n");
5759		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_RESET);
5760	}
5761	if ((portchange & USB_PORT_STAT_C_BH_RESET)
5762	    && hub_is_superspeed(hdev)) {
5763		dev_dbg(&port_dev->dev, "warm reset change\n");
5764		usb_clear_port_feature(hdev, port1,
5765				USB_PORT_FEAT_C_BH_PORT_RESET);
5766	}
5767	if (portchange & USB_PORT_STAT_C_LINK_STATE) {
5768		dev_dbg(&port_dev->dev, "link state change\n");
5769		usb_clear_port_feature(hdev, port1,
5770				USB_PORT_FEAT_C_PORT_LINK_STATE);
5771	}
5772	if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
5773		dev_warn(&port_dev->dev, "config error\n");
5774		usb_clear_port_feature(hdev, port1,
5775				USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
5776	}
5777
5778	/* skip port actions that require the port to be powered on */
5779	if (!pm_runtime_active(&port_dev->dev))
5780		return;
5781
5782	/* skip port actions if ignore_event and early_stop are true */
5783	if (port_dev->ignore_event && port_dev->early_stop)
5784		return;
5785
5786	if (hub_handle_remote_wakeup(hub, port1, portstatus, portchange))
5787		connect_change = 1;
5788
5789	/*
5790	 * Avoid trying to recover a USB3 SS.Inactive port with a warm reset if
5791	 * the device was disconnected. A 12ms disconnect detect timer in
5792	 * SS.Inactive state transitions the port to RxDetect automatically.
5793	 * SS.Inactive link error state is common during device disconnect.
5794	 */
5795	while (hub_port_warm_reset_required(hub, port1, portstatus)) {
5796		if ((i++ < DETECT_DISCONNECT_TRIES) && udev) {
5797			u16 unused;
5798
5799			msleep(20);
5800			usb_hub_port_status(hub, port1, &portstatus, &unused);
5801			dev_dbg(&port_dev->dev, "Wait for inactive link disconnect detect\n");
5802			continue;
5803		} else if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION)
5804				|| udev->state == USB_STATE_NOTATTACHED) {
5805			dev_dbg(&port_dev->dev, "do warm reset, port only\n");
5806			if (hub_port_reset(hub, port1, NULL,
5807					HUB_BH_RESET_TIME, true) < 0)
5808				hub_port_disable(hub, port1, 1);
5809		} else {
5810			dev_dbg(&port_dev->dev, "do warm reset, full device\n");
5811			usb_unlock_port(port_dev);
5812			usb_lock_device(udev);
5813			usb_reset_device(udev);
5814			usb_unlock_device(udev);
5815			usb_lock_port(port_dev);
5816			connect_change = 0;
5817		}
5818		break;
5819	}
5820
5821	if (connect_change)
5822		hub_port_connect_change(hub, port1, portstatus, portchange);
5823}
5824
5825static void hub_event(struct work_struct *work)
5826{
5827	struct usb_device *hdev;
5828	struct usb_interface *intf;
5829	struct usb_hub *hub;
5830	struct device *hub_dev;
5831	u16 hubstatus;
5832	u16 hubchange;
5833	int i, ret;
5834
5835	hub = container_of(work, struct usb_hub, events);
5836	hdev = hub->hdev;
5837	hub_dev = hub->intfdev;
5838	intf = to_usb_interface(hub_dev);
5839
5840	kcov_remote_start_usb((u64)hdev->bus->busnum);
5841
5842	dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
5843			hdev->state, hdev->maxchild,
5844			/* NOTE: expects max 15 ports... */
5845			(u16) hub->change_bits[0],
5846			(u16) hub->event_bits[0]);
5847
5848	/* Lock the device, then check to see if we were
5849	 * disconnected while waiting for the lock to succeed. */
5850	usb_lock_device(hdev);
5851	if (unlikely(hub->disconnected))
5852		goto out_hdev_lock;
5853
5854	/* If the hub has died, clean up after it */
5855	if (hdev->state == USB_STATE_NOTATTACHED) {
5856		hub->error = -ENODEV;
5857		hub_quiesce(hub, HUB_DISCONNECT);
5858		goto out_hdev_lock;
5859	}
5860
5861	/* Autoresume */
5862	ret = usb_autopm_get_interface(intf);
5863	if (ret) {
5864		dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
5865		goto out_hdev_lock;
5866	}
5867
5868	/* If this is an inactive hub, do nothing */
5869	if (hub->quiescing)
5870		goto out_autopm;
5871
5872	if (hub->error) {
5873		dev_dbg(hub_dev, "resetting for error %d\n", hub->error);
5874
5875		ret = usb_reset_device(hdev);
5876		if (ret) {
5877			dev_dbg(hub_dev, "error resetting hub: %d\n", ret);
5878			goto out_autopm;
5879		}
5880
5881		hub->nerrors = 0;
5882		hub->error = 0;
5883	}
5884
5885	/* deal with port status changes */
5886	for (i = 1; i <= hdev->maxchild; i++) {
5887		struct usb_port *port_dev = hub->ports[i - 1];
5888
5889		if (test_bit(i, hub->event_bits)
5890				|| test_bit(i, hub->change_bits)
5891				|| test_bit(i, hub->wakeup_bits)) {
5892			/*
5893			 * The get_noresume and barrier ensure that if
5894			 * the port was in the process of resuming, we
5895			 * flush that work and keep the port active for
5896			 * the duration of the port_event().  However,
5897			 * if the port is runtime pm suspended
5898			 * (powered-off), we leave it in that state, run
5899			 * an abbreviated port_event(), and move on.
5900			 */
5901			pm_runtime_get_noresume(&port_dev->dev);
5902			pm_runtime_barrier(&port_dev->dev);
5903			usb_lock_port(port_dev);
5904			port_event(hub, i);
5905			usb_unlock_port(port_dev);
5906			pm_runtime_put_sync(&port_dev->dev);
5907		}
5908	}
5909
5910	/* deal with hub status changes */
5911	if (test_and_clear_bit(0, hub->event_bits) == 0)
5912		;	/* do nothing */
5913	else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
5914		dev_err(hub_dev, "get_hub_status failed\n");
5915	else {
5916		if (hubchange & HUB_CHANGE_LOCAL_POWER) {
5917			dev_dbg(hub_dev, "power change\n");
5918			clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
5919			if (hubstatus & HUB_STATUS_LOCAL_POWER)
5920				/* FIXME: Is this always true? */
5921				hub->limited_power = 1;
5922			else
5923				hub->limited_power = 0;
5924		}
5925		if (hubchange & HUB_CHANGE_OVERCURRENT) {
5926			u16 status = 0;
5927			u16 unused;
5928
5929			dev_dbg(hub_dev, "over-current change\n");
5930			clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
5931			msleep(500);	/* Cool down */
5932			hub_power_on(hub, true);
5933			hub_hub_status(hub, &status, &unused);
5934			if (status & HUB_STATUS_OVERCURRENT)
5935				dev_err(hub_dev, "over-current condition\n");
5936		}
5937	}
5938
5939out_autopm:
5940	/* Balance the usb_autopm_get_interface() above */
5941	usb_autopm_put_interface_no_suspend(intf);
5942out_hdev_lock:
5943	usb_unlock_device(hdev);
5944
5945	/* Balance the stuff in kick_hub_wq() and allow autosuspend */
5946	usb_autopm_put_interface(intf);
5947	hub_put(hub);
5948
5949	kcov_remote_stop();
5950}
5951
5952static const struct usb_device_id hub_id_table[] = {
5953    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5954                   | USB_DEVICE_ID_MATCH_PRODUCT
5955                   | USB_DEVICE_ID_MATCH_INT_CLASS,
5956      .idVendor = USB_VENDOR_SMSC,
5957      .idProduct = USB_PRODUCT_USB5534B,
5958      .bInterfaceClass = USB_CLASS_HUB,
5959      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5960    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5961                   | USB_DEVICE_ID_MATCH_PRODUCT,
5962      .idVendor = USB_VENDOR_CYPRESS,
5963      .idProduct = USB_PRODUCT_CY7C65632,
5964      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5965    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5966			| USB_DEVICE_ID_MATCH_INT_CLASS,
5967      .idVendor = USB_VENDOR_GENESYS_LOGIC,
5968      .bInterfaceClass = USB_CLASS_HUB,
5969      .driver_info = HUB_QUIRK_CHECK_PORT_AUTOSUSPEND},
5970    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5971			| USB_DEVICE_ID_MATCH_PRODUCT,
5972      .idVendor = USB_VENDOR_TEXAS_INSTRUMENTS,
5973      .idProduct = USB_PRODUCT_TUSB8041_USB2,
5974      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5975    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5976			| USB_DEVICE_ID_MATCH_PRODUCT,
5977      .idVendor = USB_VENDOR_TEXAS_INSTRUMENTS,
5978      .idProduct = USB_PRODUCT_TUSB8041_USB3,
5979      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5980	{ .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5981			| USB_DEVICE_ID_MATCH_PRODUCT,
5982	  .idVendor = USB_VENDOR_MICROCHIP,
5983	  .idProduct = USB_PRODUCT_USB4913,
5984	  .driver_info = HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL},
5985	{ .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5986			| USB_DEVICE_ID_MATCH_PRODUCT,
5987	  .idVendor = USB_VENDOR_MICROCHIP,
5988	  .idProduct = USB_PRODUCT_USB4914,
5989	  .driver_info = HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL},
5990	{ .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5991			| USB_DEVICE_ID_MATCH_PRODUCT,
5992	  .idVendor = USB_VENDOR_MICROCHIP,
5993	  .idProduct = USB_PRODUCT_USB4915,
5994	  .driver_info = HUB_QUIRK_REDUCE_FRAME_INTR_BINTERVAL},
5995    { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
5996      .bDeviceClass = USB_CLASS_HUB},
5997    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
5998      .bInterfaceClass = USB_CLASS_HUB},
5999    { }						/* Terminating entry */
6000};
6001
6002MODULE_DEVICE_TABLE(usb, hub_id_table);
6003
6004static struct usb_driver hub_driver = {
6005	.name =		"hub",
6006	.probe =	hub_probe,
6007	.disconnect =	hub_disconnect,
6008	.suspend =	hub_suspend,
6009	.resume =	hub_resume,
6010	.reset_resume =	hub_reset_resume,
6011	.pre_reset =	hub_pre_reset,
6012	.post_reset =	hub_post_reset,
6013	.unlocked_ioctl = hub_ioctl,
6014	.id_table =	hub_id_table,
6015	.supports_autosuspend =	1,
6016};
6017
6018int usb_hub_init(void)
6019{
6020	if (usb_register(&hub_driver) < 0) {
6021		printk(KERN_ERR "%s: can't register hub driver\n",
6022			usbcore_name);
6023		return -1;
6024	}
6025
6026	/*
6027	 * The workqueue needs to be freezable to avoid interfering with
6028	 * USB-PERSIST port handover. Otherwise it might see that a full-speed
6029	 * device was gone before the EHCI controller had handed its port
6030	 * over to the companion full-speed controller.
6031	 */
6032	hub_wq = alloc_workqueue("usb_hub_wq", WQ_FREEZABLE, 0);
6033	if (hub_wq)
6034		return 0;
6035
6036	/* Fall through if kernel_thread failed */
6037	usb_deregister(&hub_driver);
6038	pr_err("%s: can't allocate workqueue for usb hub\n", usbcore_name);
6039
6040	return -1;
6041}
6042
6043void usb_hub_cleanup(void)
6044{
6045	destroy_workqueue(hub_wq);
6046
6047	/*
6048	 * Hub resources are freed for us by usb_deregister. It calls
6049	 * usb_driver_purge on every device which in turn calls that
6050	 * devices disconnect function if it is using this driver.
6051	 * The hub_disconnect function takes care of releasing the
6052	 * individual hub resources. -greg
6053	 */
6054	usb_deregister(&hub_driver);
6055} /* usb_hub_cleanup() */
6056
6057/**
6058 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
6059 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
6060 *
6061 * WARNING - don't use this routine to reset a composite device
6062 * (one with multiple interfaces owned by separate drivers)!
6063 * Use usb_reset_device() instead.
6064 *
6065 * Do a port reset, reassign the device's address, and establish its
6066 * former operating configuration.  If the reset fails, or the device's
6067 * descriptors change from their values before the reset, or the original
6068 * configuration and altsettings cannot be restored, a flag will be set
6069 * telling hub_wq to pretend the device has been disconnected and then
6070 * re-connected.  All drivers will be unbound, and the device will be
6071 * re-enumerated and probed all over again.
6072 *
6073 * Return: 0 if the reset succeeded, -ENODEV if the device has been
6074 * flagged for logical disconnection, or some other negative error code
6075 * if the reset wasn't even attempted.
6076 *
6077 * Note:
6078 * The caller must own the device lock and the port lock, the latter is
6079 * taken by usb_reset_device().  For example, it's safe to use
6080 * usb_reset_device() from a driver probe() routine after downloading
6081 * new firmware.  For calls that might not occur during probe(), drivers
6082 * should lock the device using usb_lock_device_for_reset().
6083 *
6084 * Locking exception: This routine may also be called from within an
6085 * autoresume handler.  Such usage won't conflict with other tasks
6086 * holding the device lock because these tasks should always call
6087 * usb_autopm_resume_device(), thereby preventing any unwanted
6088 * autoresume.  The autoresume handler is expected to have already
6089 * acquired the port lock before calling this routine.
6090 */
6091static int usb_reset_and_verify_device(struct usb_device *udev)
6092{
6093	struct usb_device		*parent_hdev = udev->parent;
6094	struct usb_hub			*parent_hub;
6095	struct usb_hcd			*hcd = bus_to_hcd(udev->bus);
6096	struct usb_device_descriptor	descriptor;
6097	struct usb_host_bos		*bos;
6098	int				i, j, ret = 0;
6099	int				port1 = udev->portnum;
6100
6101	if (udev->state == USB_STATE_NOTATTACHED ||
6102			udev->state == USB_STATE_SUSPENDED) {
6103		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
6104				udev->state);
6105		return -EINVAL;
6106	}
6107
6108	if (!parent_hdev)
6109		return -EISDIR;
6110
6111	parent_hub = usb_hub_to_struct_hub(parent_hdev);
6112
6113	/* Disable USB2 hardware LPM.
6114	 * It will be re-enabled by the enumeration process.
6115	 */
6116	usb_disable_usb2_hardware_lpm(udev);
6117
6118	bos = udev->bos;
6119	udev->bos = NULL;
6120
6121	mutex_lock(hcd->address0_mutex);
6122
6123	for (i = 0; i < PORT_INIT_TRIES; ++i) {
6124		if (hub_port_stop_enumerate(parent_hub, port1, i)) {
6125			ret = -ENODEV;
6126			break;
6127		}
6128
6129		/* ep0 maxpacket size may change; let the HCD know about it.
6130		 * Other endpoints will be handled by re-enumeration. */
6131		usb_ep0_reinit(udev);
6132		ret = hub_port_init(parent_hub, udev, port1, i, &descriptor);
6133		if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
6134			break;
6135	}
6136	mutex_unlock(hcd->address0_mutex);
6137
6138	if (ret < 0)
6139		goto re_enumerate;
6140
6141	/* Device might have changed firmware (DFU or similar) */
6142	if (descriptors_changed(udev, &descriptor, bos)) {
6143		dev_info(&udev->dev, "device firmware changed\n");
 
6144		goto re_enumerate;
6145	}
6146
6147	/* Restore the device's previous configuration */
6148	if (!udev->actconfig)
6149		goto done;
6150
6151	mutex_lock(hcd->bandwidth_mutex);
6152	ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
6153	if (ret < 0) {
6154		dev_warn(&udev->dev,
6155				"Busted HC?  Not enough HCD resources for "
6156				"old configuration.\n");
6157		mutex_unlock(hcd->bandwidth_mutex);
6158		goto re_enumerate;
6159	}
6160	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
6161			USB_REQ_SET_CONFIGURATION, 0,
6162			udev->actconfig->desc.bConfigurationValue, 0,
6163			NULL, 0, USB_CTRL_SET_TIMEOUT);
6164	if (ret < 0) {
6165		dev_err(&udev->dev,
6166			"can't restore configuration #%d (error=%d)\n",
6167			udev->actconfig->desc.bConfigurationValue, ret);
6168		mutex_unlock(hcd->bandwidth_mutex);
6169		goto re_enumerate;
6170	}
6171	mutex_unlock(hcd->bandwidth_mutex);
6172	usb_set_device_state(udev, USB_STATE_CONFIGURED);
6173
6174	/* Put interfaces back into the same altsettings as before.
6175	 * Don't bother to send the Set-Interface request for interfaces
6176	 * that were already in altsetting 0; besides being unnecessary,
6177	 * many devices can't handle it.  Instead just reset the host-side
6178	 * endpoint state.
6179	 */
6180	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
6181		struct usb_host_config *config = udev->actconfig;
6182		struct usb_interface *intf = config->interface[i];
6183		struct usb_interface_descriptor *desc;
6184
6185		desc = &intf->cur_altsetting->desc;
6186		if (desc->bAlternateSetting == 0) {
6187			usb_disable_interface(udev, intf, true);
6188			usb_enable_interface(udev, intf, true);
6189			ret = 0;
6190		} else {
6191			/* Let the bandwidth allocation function know that this
6192			 * device has been reset, and it will have to use
6193			 * alternate setting 0 as the current alternate setting.
6194			 */
6195			intf->resetting_device = 1;
6196			ret = usb_set_interface(udev, desc->bInterfaceNumber,
6197					desc->bAlternateSetting);
6198			intf->resetting_device = 0;
6199		}
6200		if (ret < 0) {
6201			dev_err(&udev->dev, "failed to restore interface %d "
6202				"altsetting %d (error=%d)\n",
6203				desc->bInterfaceNumber,
6204				desc->bAlternateSetting,
6205				ret);
6206			goto re_enumerate;
6207		}
6208		/* Resetting also frees any allocated streams */
6209		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++)
6210			intf->cur_altsetting->endpoint[j].streams = 0;
6211	}
6212
6213done:
6214	/* Now that the alt settings are re-installed, enable LTM and LPM. */
6215	usb_enable_usb2_hardware_lpm(udev);
6216	usb_unlocked_enable_lpm(udev);
6217	usb_enable_ltm(udev);
6218	usb_release_bos_descriptor(udev);
6219	udev->bos = bos;
6220	return 0;
6221
6222re_enumerate:
6223	usb_release_bos_descriptor(udev);
6224	udev->bos = bos;
6225	hub_port_logical_disconnect(parent_hub, port1);
6226	return -ENODEV;
6227}
6228
6229/**
6230 * usb_reset_device - warn interface drivers and perform a USB port reset
6231 * @udev: device to reset (not in NOTATTACHED state)
6232 *
6233 * Warns all drivers bound to registered interfaces (using their pre_reset
6234 * method), performs the port reset, and then lets the drivers know that
6235 * the reset is over (using their post_reset method).
6236 *
6237 * Return: The same as for usb_reset_and_verify_device().
6238 * However, if a reset is already in progress (for instance, if a
6239 * driver doesn't have pre_reset() or post_reset() callbacks, and while
6240 * being unbound or re-bound during the ongoing reset its disconnect()
6241 * or probe() routine tries to perform a second, nested reset), the
6242 * routine returns -EINPROGRESS.
6243 *
6244 * Note:
6245 * The caller must own the device lock.  For example, it's safe to use
6246 * this from a driver probe() routine after downloading new firmware.
6247 * For calls that might not occur during probe(), drivers should lock
6248 * the device using usb_lock_device_for_reset().
6249 *
6250 * If an interface is currently being probed or disconnected, we assume
6251 * its driver knows how to handle resets.  For all other interfaces,
6252 * if the driver doesn't have pre_reset and post_reset methods then
6253 * we attempt to unbind it and rebind afterward.
6254 */
6255int usb_reset_device(struct usb_device *udev)
6256{
6257	int ret;
6258	int i;
6259	unsigned int noio_flag;
6260	struct usb_port *port_dev;
6261	struct usb_host_config *config = udev->actconfig;
6262	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
6263
6264	if (udev->state == USB_STATE_NOTATTACHED) {
6265		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
6266				udev->state);
6267		return -EINVAL;
6268	}
6269
6270	if (!udev->parent) {
6271		/* this requires hcd-specific logic; see ohci_restart() */
6272		dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
6273		return -EISDIR;
6274	}
6275
6276	if (udev->reset_in_progress)
6277		return -EINPROGRESS;
6278	udev->reset_in_progress = 1;
6279
6280	port_dev = hub->ports[udev->portnum - 1];
6281
6282	/*
6283	 * Don't allocate memory with GFP_KERNEL in current
6284	 * context to avoid possible deadlock if usb mass
6285	 * storage interface or usbnet interface(iSCSI case)
6286	 * is included in current configuration. The easist
6287	 * approach is to do it for every device reset,
6288	 * because the device 'memalloc_noio' flag may have
6289	 * not been set before reseting the usb device.
6290	 */
6291	noio_flag = memalloc_noio_save();
6292
6293	/* Prevent autosuspend during the reset */
6294	usb_autoresume_device(udev);
6295
6296	if (config) {
6297		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
6298			struct usb_interface *cintf = config->interface[i];
6299			struct usb_driver *drv;
6300			int unbind = 0;
6301
6302			if (cintf->dev.driver) {
6303				drv = to_usb_driver(cintf->dev.driver);
6304				if (drv->pre_reset && drv->post_reset)
6305					unbind = (drv->pre_reset)(cintf);
6306				else if (cintf->condition ==
6307						USB_INTERFACE_BOUND)
6308					unbind = 1;
6309				if (unbind)
6310					usb_forced_unbind_intf(cintf);
6311			}
6312		}
6313	}
6314
6315	usb_lock_port(port_dev);
6316	ret = usb_reset_and_verify_device(udev);
6317	usb_unlock_port(port_dev);
6318
6319	if (config) {
6320		for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
6321			struct usb_interface *cintf = config->interface[i];
6322			struct usb_driver *drv;
6323			int rebind = cintf->needs_binding;
6324
6325			if (!rebind && cintf->dev.driver) {
6326				drv = to_usb_driver(cintf->dev.driver);
6327				if (drv->post_reset)
6328					rebind = (drv->post_reset)(cintf);
6329				else if (cintf->condition ==
6330						USB_INTERFACE_BOUND)
6331					rebind = 1;
6332				if (rebind)
6333					cintf->needs_binding = 1;
6334			}
6335		}
6336
6337		/* If the reset failed, hub_wq will unbind drivers later */
6338		if (ret == 0)
6339			usb_unbind_and_rebind_marked_interfaces(udev);
6340	}
6341
6342	usb_autosuspend_device(udev);
6343	memalloc_noio_restore(noio_flag);
6344	udev->reset_in_progress = 0;
6345	return ret;
6346}
6347EXPORT_SYMBOL_GPL(usb_reset_device);
6348
6349
6350/**
6351 * usb_queue_reset_device - Reset a USB device from an atomic context
6352 * @iface: USB interface belonging to the device to reset
6353 *
6354 * This function can be used to reset a USB device from an atomic
6355 * context, where usb_reset_device() won't work (as it blocks).
6356 *
6357 * Doing a reset via this method is functionally equivalent to calling
6358 * usb_reset_device(), except for the fact that it is delayed to a
6359 * workqueue. This means that any drivers bound to other interfaces
6360 * might be unbound, as well as users from usbfs in user space.
6361 *
6362 * Corner cases:
6363 *
6364 * - Scheduling two resets at the same time from two different drivers
6365 *   attached to two different interfaces of the same device is
6366 *   possible; depending on how the driver attached to each interface
6367 *   handles ->pre_reset(), the second reset might happen or not.
6368 *
6369 * - If the reset is delayed so long that the interface is unbound from
6370 *   its driver, the reset will be skipped.
6371 *
6372 * - This function can be called during .probe().  It can also be called
6373 *   during .disconnect(), but doing so is pointless because the reset
6374 *   will not occur.  If you really want to reset the device during
6375 *   .disconnect(), call usb_reset_device() directly -- but watch out
6376 *   for nested unbinding issues!
6377 */
6378void usb_queue_reset_device(struct usb_interface *iface)
6379{
6380	if (schedule_work(&iface->reset_ws))
6381		usb_get_intf(iface);
6382}
6383EXPORT_SYMBOL_GPL(usb_queue_reset_device);
6384
6385/**
6386 * usb_hub_find_child - Get the pointer of child device
6387 * attached to the port which is specified by @port1.
6388 * @hdev: USB device belonging to the usb hub
6389 * @port1: port num to indicate which port the child device
6390 *	is attached to.
6391 *
6392 * USB drivers call this function to get hub's child device
6393 * pointer.
6394 *
6395 * Return: %NULL if input param is invalid and
6396 * child's usb_device pointer if non-NULL.
6397 */
6398struct usb_device *usb_hub_find_child(struct usb_device *hdev,
6399		int port1)
6400{
6401	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6402
6403	if (port1 < 1 || port1 > hdev->maxchild)
6404		return NULL;
6405	return hub->ports[port1 - 1]->child;
6406}
6407EXPORT_SYMBOL_GPL(usb_hub_find_child);
6408
6409void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
6410		struct usb_hub_descriptor *desc)
6411{
6412	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6413	enum usb_port_connect_type connect_type;
6414	int i;
6415
6416	if (!hub)
6417		return;
6418
6419	if (!hub_is_superspeed(hdev)) {
6420		for (i = 1; i <= hdev->maxchild; i++) {
6421			struct usb_port *port_dev = hub->ports[i - 1];
6422
6423			connect_type = port_dev->connect_type;
6424			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6425				u8 mask = 1 << (i%8);
6426
6427				if (!(desc->u.hs.DeviceRemovable[i/8] & mask)) {
6428					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6429					desc->u.hs.DeviceRemovable[i/8]	|= mask;
6430				}
6431			}
6432		}
6433	} else {
6434		u16 port_removable = le16_to_cpu(desc->u.ss.DeviceRemovable);
6435
6436		for (i = 1; i <= hdev->maxchild; i++) {
6437			struct usb_port *port_dev = hub->ports[i - 1];
6438
6439			connect_type = port_dev->connect_type;
6440			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6441				u16 mask = 1 << i;
6442
6443				if (!(port_removable & mask)) {
6444					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6445					port_removable |= mask;
6446				}
6447			}
6448		}
6449
6450		desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
6451	}
6452}
6453
6454#ifdef CONFIG_ACPI
6455/**
6456 * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
6457 * @hdev: USB device belonging to the usb hub
6458 * @port1: port num of the port
6459 *
6460 * Return: Port's acpi handle if successful, %NULL if params are
6461 * invalid.
6462 */
6463acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev,
6464	int port1)
6465{
6466	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6467
6468	if (!hub)
6469		return NULL;
6470
6471	return ACPI_HANDLE(&hub->ports[port1 - 1]->dev);
6472}
6473#endif