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 "otg_productlist.h"
  41
  42#define USB_VENDOR_GENESYS_LOGIC		0x05e3
  43#define USB_VENDOR_SMSC				0x0424
  44#define USB_PRODUCT_USB5534B			0x5534
  45#define USB_VENDOR_CYPRESS			0x04b4
  46#define USB_PRODUCT_CY7C65632			0x6570
  47#define USB_VENDOR_TEXAS_INSTRUMENTS		0x0451
  48#define USB_PRODUCT_TUSB8041_USB3		0x8140
  49#define USB_PRODUCT_TUSB8041_USB2		0x8142
  50#define HUB_QUIRK_CHECK_PORT_AUTOSUSPEND	0x01
  51#define HUB_QUIRK_DISABLE_AUTOSUSPEND		0x02
  52
  53#define USB_TP_TRANSMISSION_DELAY	40	/* ns */
  54#define USB_TP_TRANSMISSION_DELAY_MAX	65535	/* ns */
  55#define USB_PING_RESPONSE_TIME		400	/* ns */
  56
  57/* Protect struct usb_device->state and ->children members
  58 * Note: Both are also protected by ->dev.sem, except that ->state can
  59 * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  60static DEFINE_SPINLOCK(device_state_lock);
  61
  62/* workqueue to process hub events */
  63static struct workqueue_struct *hub_wq;
  64static void hub_event(struct work_struct *work);
  65
  66/* synchronize hub-port add/remove and peering operations */
  67DEFINE_MUTEX(usb_port_peer_mutex);
  68
  69/* cycle leds on hubs that aren't blinking for attention */
  70static bool blinkenlights;
  71module_param(blinkenlights, bool, S_IRUGO);
  72MODULE_PARM_DESC(blinkenlights, "true to cycle leds on hubs");
  73
  74/*
  75 * Device SATA8000 FW1.0 from DATAST0R Technology Corp requires about
  76 * 10 seconds to send reply for the initial 64-byte descriptor request.
  77 */
  78/* define initial 64-byte descriptor request timeout in milliseconds */
  79static int initial_descriptor_timeout = USB_CTRL_GET_TIMEOUT;
  80module_param(initial_descriptor_timeout, int, S_IRUGO|S_IWUSR);
  81MODULE_PARM_DESC(initial_descriptor_timeout,
  82		"initial 64-byte descriptor request timeout in milliseconds "
  83		"(default 5000 - 5.0 seconds)");
  84
  85/*
  86 * As of 2.6.10 we introduce a new USB device initialization scheme which
  87 * closely resembles the way Windows works.  Hopefully it will be compatible
  88 * with a wider range of devices than the old scheme.  However some previously
  89 * working devices may start giving rise to "device not accepting address"
  90 * errors; if that happens the user can try the old scheme by adjusting the
  91 * following module parameters.
  92 *
  93 * For maximum flexibility there are two boolean parameters to control the
  94 * hub driver's behavior.  On the first initialization attempt, if the
  95 * "old_scheme_first" parameter is set then the old scheme will be used,
  96 * otherwise the new scheme is used.  If that fails and "use_both_schemes"
  97 * is set, then the driver will make another attempt, using the other scheme.
  98 */
  99static bool old_scheme_first;
 100module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
 101MODULE_PARM_DESC(old_scheme_first,
 102		 "start with the old device initialization scheme");
 103
 104static bool use_both_schemes = true;
 105module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
 106MODULE_PARM_DESC(use_both_schemes,
 107		"try the other device initialization scheme if the "
 108		"first one fails");
 109
 110/* Mutual exclusion for EHCI CF initialization.  This interferes with
 111 * port reset on some companion controllers.
 112 */
 113DECLARE_RWSEM(ehci_cf_port_reset_rwsem);
 114EXPORT_SYMBOL_GPL(ehci_cf_port_reset_rwsem);
 115
 116#define HUB_DEBOUNCE_TIMEOUT	2000
 117#define HUB_DEBOUNCE_STEP	  25
 118#define HUB_DEBOUNCE_STABLE	 100
 119
 120static void hub_release(struct kref *kref);
 121static int usb_reset_and_verify_device(struct usb_device *udev);
 122static int hub_port_disable(struct usb_hub *hub, int port1, int set_state);
 123static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
 124		u16 portstatus);
 125
 126static inline char *portspeed(struct usb_hub *hub, int portstatus)
 127{
 128	if (hub_is_superspeedplus(hub->hdev))
 129		return "10.0 Gb/s";
 130	if (hub_is_superspeed(hub->hdev))
 131		return "5.0 Gb/s";
 132	if (portstatus & USB_PORT_STAT_HIGH_SPEED)
 133		return "480 Mb/s";
 134	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
 135		return "1.5 Mb/s";
 136	else
 137		return "12 Mb/s";
 138}
 139
 140/* Note that hdev or one of its children must be locked! */
 141struct usb_hub *usb_hub_to_struct_hub(struct usb_device *hdev)
 142{
 143	if (!hdev || !hdev->actconfig || !hdev->maxchild)
 144		return NULL;
 145	return usb_get_intfdata(hdev->actconfig->interface[0]);
 146}
 147
 148int usb_device_supports_lpm(struct usb_device *udev)
 149{
 150	/* Some devices have trouble with LPM */
 151	if (udev->quirks & USB_QUIRK_NO_LPM)
 152		return 0;
 153
 154	/* USB 2.1 (and greater) devices indicate LPM support through
 155	 * their USB 2.0 Extended Capabilities BOS descriptor.
 156	 */
 157	if (udev->speed == USB_SPEED_HIGH || udev->speed == USB_SPEED_FULL) {
 158		if (udev->bos->ext_cap &&
 159			(USB_LPM_SUPPORT &
 160			 le32_to_cpu(udev->bos->ext_cap->bmAttributes)))
 161			return 1;
 162		return 0;
 163	}
 164
 165	/*
 166	 * According to the USB 3.0 spec, all USB 3.0 devices must support LPM.
 167	 * However, there are some that don't, and they set the U1/U2 exit
 168	 * latencies to zero.
 169	 */
 170	if (!udev->bos->ss_cap) {
 171		dev_info(&udev->dev, "No LPM exit latency info found, disabling LPM.\n");
 172		return 0;
 173	}
 174
 175	if (udev->bos->ss_cap->bU1devExitLat == 0 &&
 176			udev->bos->ss_cap->bU2DevExitLat == 0) {
 177		if (udev->parent)
 178			dev_info(&udev->dev, "LPM exit latency is zeroed, disabling LPM.\n");
 179		else
 180			dev_info(&udev->dev, "We don't know the algorithms for LPM for this host, disabling LPM.\n");
 181		return 0;
 182	}
 183
 184	if (!udev->parent || udev->parent->lpm_capable)
 185		return 1;
 186	return 0;
 187}
 188
 189/*
 190 * Set the Maximum Exit Latency (MEL) for the host to wakup up the path from
 191 * U1/U2, send a PING to the device and receive a PING_RESPONSE.
 192 * See USB 3.1 section C.1.5.2
 193 */
 194static void usb_set_lpm_mel(struct usb_device *udev,
 195		struct usb3_lpm_parameters *udev_lpm_params,
 196		unsigned int udev_exit_latency,
 197		struct usb_hub *hub,
 198		struct usb3_lpm_parameters *hub_lpm_params,
 199		unsigned int hub_exit_latency)
 200{
 201	unsigned int total_mel;
 
 
 202
 203	/*
 204	 * tMEL1. time to transition path from host to device into U0.
 205	 * MEL for parent already contains the delay up to parent, so only add
 206	 * the exit latency for the last link (pick the slower exit latency),
 207	 * and the hub header decode latency. See USB 3.1 section C 2.2.1
 208	 * Store MEL in nanoseconds
 
 
 209	 */
 210	total_mel = hub_lpm_params->mel +
 211		max(udev_exit_latency, hub_exit_latency) * 1000 +
 212		hub->descriptor->u.ss.bHubHdrDecLat * 100;
 213
 214	/*
 215	 * tMEL2. Time to submit PING packet. Sum of tTPTransmissionDelay for
 216	 * each link + wHubDelay for each hub. Add only for last link.
 217	 * tMEL4, the time for PING_RESPONSE to traverse upstream is similar.
 218	 * Multiply by 2 to include it as well.
 219	 */
 220	total_mel += (__le16_to_cpu(hub->descriptor->u.ss.wHubDelay) +
 221		      USB_TP_TRANSMISSION_DELAY) * 2;
 222
 223	/*
 224	 * tMEL3, tPingResponse. Time taken by device to generate PING_RESPONSE
 225	 * after receiving PING. Also add 2100ns as stated in USB 3.1 C 1.5.2.4
 226	 * to cover the delay if the PING_RESPONSE is queued behind a Max Packet
 227	 * Size DP.
 228	 * Note these delays should be added only once for the entire path, so
 229	 * add them to the MEL of the device connected to the roothub.
 230	 */
 231	if (!hub->hdev->parent)
 232		total_mel += USB_PING_RESPONSE_TIME + 2100;
 
 
 
 
 233
 234	udev_lpm_params->mel = total_mel;
 235}
 236
 237/*
 238 * Set the maximum Device to Host Exit Latency (PEL) for the device to initiate
 239 * a transition from either U1 or U2.
 240 */
 241static void usb_set_lpm_pel(struct usb_device *udev,
 242		struct usb3_lpm_parameters *udev_lpm_params,
 243		unsigned int udev_exit_latency,
 244		struct usb_hub *hub,
 245		struct usb3_lpm_parameters *hub_lpm_params,
 246		unsigned int hub_exit_latency,
 247		unsigned int port_to_port_exit_latency)
 248{
 249	unsigned int first_link_pel;
 250	unsigned int hub_pel;
 251
 252	/*
 253	 * First, the device sends an LFPS to transition the link between the
 254	 * device and the parent hub into U0.  The exit latency is the bigger of
 255	 * the device exit latency or the hub exit latency.
 256	 */
 257	if (udev_exit_latency > hub_exit_latency)
 258		first_link_pel = udev_exit_latency * 1000;
 259	else
 260		first_link_pel = hub_exit_latency * 1000;
 261
 262	/*
 263	 * When the hub starts to receive the LFPS, there is a slight delay for
 264	 * it to figure out that one of the ports is sending an LFPS.  Then it
 265	 * will forward the LFPS to its upstream link.  The exit latency is the
 266	 * delay, plus the PEL that we calculated for this hub.
 267	 */
 268	hub_pel = port_to_port_exit_latency * 1000 + hub_lpm_params->pel;
 269
 270	/*
 271	 * According to figure C-7 in the USB 3.0 spec, the PEL for this device
 272	 * is the greater of the two exit latencies.
 273	 */
 274	if (first_link_pel > hub_pel)
 275		udev_lpm_params->pel = first_link_pel;
 276	else
 277		udev_lpm_params->pel = hub_pel;
 278}
 279
 280/*
 281 * Set the System Exit Latency (SEL) to indicate the total worst-case time from
 282 * when a device initiates a transition to U0, until when it will receive the
 283 * first packet from the host controller.
 284 *
 285 * Section C.1.5.1 describes the four components to this:
 286 *  - t1: device PEL
 287 *  - t2: time for the ERDY to make it from the device to the host.
 288 *  - t3: a host-specific delay to process the ERDY.
 289 *  - t4: time for the packet to make it from the host to the device.
 290 *
 291 * t3 is specific to both the xHCI host and the platform the host is integrated
 292 * into.  The Intel HW folks have said it's negligible, FIXME if a different
 293 * vendor says otherwise.
 294 */
 295static void usb_set_lpm_sel(struct usb_device *udev,
 296		struct usb3_lpm_parameters *udev_lpm_params)
 297{
 298	struct usb_device *parent;
 299	unsigned int num_hubs;
 300	unsigned int total_sel;
 301
 302	/* t1 = device PEL */
 303	total_sel = udev_lpm_params->pel;
 304	/* How many external hubs are in between the device & the root port. */
 305	for (parent = udev->parent, num_hubs = 0; parent->parent;
 306			parent = parent->parent)
 307		num_hubs++;
 308	/* t2 = 2.1us + 250ns * (num_hubs - 1) */
 309	if (num_hubs > 0)
 310		total_sel += 2100 + 250 * (num_hubs - 1);
 311
 312	/* t4 = 250ns * num_hubs */
 313	total_sel += 250 * num_hubs;
 314
 315	udev_lpm_params->sel = total_sel;
 316}
 317
 318static void usb_set_lpm_parameters(struct usb_device *udev)
 319{
 320	struct usb_hub *hub;
 321	unsigned int port_to_port_delay;
 322	unsigned int udev_u1_del;
 323	unsigned int udev_u2_del;
 324	unsigned int hub_u1_del;
 325	unsigned int hub_u2_del;
 326
 327	if (!udev->lpm_capable || udev->speed < USB_SPEED_SUPER)
 328		return;
 329
 330	hub = usb_hub_to_struct_hub(udev->parent);
 331	/* It doesn't take time to transition the roothub into U0, since it
 332	 * doesn't have an upstream link.
 333	 */
 334	if (!hub)
 335		return;
 336
 337	udev_u1_del = udev->bos->ss_cap->bU1devExitLat;
 338	udev_u2_del = le16_to_cpu(udev->bos->ss_cap->bU2DevExitLat);
 339	hub_u1_del = udev->parent->bos->ss_cap->bU1devExitLat;
 340	hub_u2_del = le16_to_cpu(udev->parent->bos->ss_cap->bU2DevExitLat);
 341
 342	usb_set_lpm_mel(udev, &udev->u1_params, udev_u1_del,
 343			hub, &udev->parent->u1_params, hub_u1_del);
 344
 345	usb_set_lpm_mel(udev, &udev->u2_params, udev_u2_del,
 346			hub, &udev->parent->u2_params, hub_u2_del);
 347
 348	/*
 349	 * Appendix C, section C.2.2.2, says that there is a slight delay from
 350	 * when the parent hub notices the downstream port is trying to
 351	 * transition to U0 to when the hub initiates a U0 transition on its
 352	 * upstream port.  The section says the delays are tPort2PortU1EL and
 353	 * tPort2PortU2EL, but it doesn't define what they are.
 354	 *
 355	 * The hub chapter, sections 10.4.2.4 and 10.4.2.5 seem to be talking
 356	 * about the same delays.  Use the maximum delay calculations from those
 357	 * sections.  For U1, it's tHubPort2PortExitLat, which is 1us max.  For
 358	 * U2, it's tHubPort2PortExitLat + U2DevExitLat - U1DevExitLat.  I
 359	 * assume the device exit latencies they are talking about are the hub
 360	 * exit latencies.
 361	 *
 362	 * What do we do if the U2 exit latency is less than the U1 exit
 363	 * latency?  It's possible, although not likely...
 364	 */
 365	port_to_port_delay = 1;
 366
 367	usb_set_lpm_pel(udev, &udev->u1_params, udev_u1_del,
 368			hub, &udev->parent->u1_params, hub_u1_del,
 369			port_to_port_delay);
 370
 371	if (hub_u2_del > hub_u1_del)
 372		port_to_port_delay = 1 + hub_u2_del - hub_u1_del;
 373	else
 374		port_to_port_delay = 1 + hub_u1_del;
 375
 376	usb_set_lpm_pel(udev, &udev->u2_params, udev_u2_del,
 377			hub, &udev->parent->u2_params, hub_u2_del,
 378			port_to_port_delay);
 379
 380	/* Now that we've got PEL, calculate SEL. */
 381	usb_set_lpm_sel(udev, &udev->u1_params);
 382	usb_set_lpm_sel(udev, &udev->u2_params);
 383}
 384
 385/* USB 2.0 spec Section 11.24.4.5 */
 386static int get_hub_descriptor(struct usb_device *hdev,
 387		struct usb_hub_descriptor *desc)
 388{
 389	int i, ret, size;
 390	unsigned dtype;
 391
 392	if (hub_is_superspeed(hdev)) {
 393		dtype = USB_DT_SS_HUB;
 394		size = USB_DT_SS_HUB_SIZE;
 395	} else {
 396		dtype = USB_DT_HUB;
 397		size = sizeof(struct usb_hub_descriptor);
 398	}
 399
 400	for (i = 0; i < 3; i++) {
 401		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 402			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 403			dtype << 8, 0, desc, size,
 404			USB_CTRL_GET_TIMEOUT);
 405		if (hub_is_superspeed(hdev)) {
 406			if (ret == size)
 407				return ret;
 408		} else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {
 409			/* Make sure we have the DeviceRemovable field. */
 410			size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;
 411			if (ret < size)
 412				return -EMSGSIZE;
 413			return ret;
 414		}
 415	}
 416	return -EINVAL;
 417}
 418
 419/*
 420 * USB 2.0 spec Section 11.24.2.1
 421 */
 422static int clear_hub_feature(struct usb_device *hdev, int feature)
 423{
 424	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 425		USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 426}
 427
 428/*
 429 * USB 2.0 spec Section 11.24.2.2
 430 */
 431int usb_clear_port_feature(struct usb_device *hdev, int port1, int feature)
 432{
 433	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 434		USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 435		NULL, 0, 1000);
 436}
 437
 438/*
 439 * USB 2.0 spec Section 11.24.2.13
 440 */
 441static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 442{
 443	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 444		USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 445		NULL, 0, 1000);
 446}
 447
 448static char *to_led_name(int selector)
 449{
 450	switch (selector) {
 451	case HUB_LED_AMBER:
 452		return "amber";
 453	case HUB_LED_GREEN:
 454		return "green";
 455	case HUB_LED_OFF:
 456		return "off";
 457	case HUB_LED_AUTO:
 458		return "auto";
 459	default:
 460		return "??";
 461	}
 462}
 463
 464/*
 465 * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 466 * for info about using port indicators
 467 */
 468static void set_port_led(struct usb_hub *hub, int port1, int selector)
 469{
 470	struct usb_port *port_dev = hub->ports[port1 - 1];
 471	int status;
 472
 473	status = set_port_feature(hub->hdev, (selector << 8) | port1,
 474			USB_PORT_FEAT_INDICATOR);
 475	dev_dbg(&port_dev->dev, "indicator %s status %d\n",
 476		to_led_name(selector), status);
 477}
 478
 479#define	LED_CYCLE_PERIOD	((2*HZ)/3)
 480
 481static void led_work(struct work_struct *work)
 482{
 483	struct usb_hub		*hub =
 484		container_of(work, struct usb_hub, leds.work);
 485	struct usb_device	*hdev = hub->hdev;
 486	unsigned		i;
 487	unsigned		changed = 0;
 488	int			cursor = -1;
 489
 490	if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 491		return;
 492
 493	for (i = 0; i < hdev->maxchild; i++) {
 494		unsigned	selector, mode;
 495
 496		/* 30%-50% duty cycle */
 497
 498		switch (hub->indicator[i]) {
 499		/* cycle marker */
 500		case INDICATOR_CYCLE:
 501			cursor = i;
 502			selector = HUB_LED_AUTO;
 503			mode = INDICATOR_AUTO;
 504			break;
 505		/* blinking green = sw attention */
 506		case INDICATOR_GREEN_BLINK:
 507			selector = HUB_LED_GREEN;
 508			mode = INDICATOR_GREEN_BLINK_OFF;
 509			break;
 510		case INDICATOR_GREEN_BLINK_OFF:
 511			selector = HUB_LED_OFF;
 512			mode = INDICATOR_GREEN_BLINK;
 513			break;
 514		/* blinking amber = hw attention */
 515		case INDICATOR_AMBER_BLINK:
 516			selector = HUB_LED_AMBER;
 517			mode = INDICATOR_AMBER_BLINK_OFF;
 518			break;
 519		case INDICATOR_AMBER_BLINK_OFF:
 520			selector = HUB_LED_OFF;
 521			mode = INDICATOR_AMBER_BLINK;
 522			break;
 523		/* blink green/amber = reserved */
 524		case INDICATOR_ALT_BLINK:
 525			selector = HUB_LED_GREEN;
 526			mode = INDICATOR_ALT_BLINK_OFF;
 527			break;
 528		case INDICATOR_ALT_BLINK_OFF:
 529			selector = HUB_LED_AMBER;
 530			mode = INDICATOR_ALT_BLINK;
 531			break;
 532		default:
 533			continue;
 534		}
 535		if (selector != HUB_LED_AUTO)
 536			changed = 1;
 537		set_port_led(hub, i + 1, selector);
 538		hub->indicator[i] = mode;
 539	}
 540	if (!changed && blinkenlights) {
 541		cursor++;
 542		cursor %= hdev->maxchild;
 543		set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 544		hub->indicator[cursor] = INDICATOR_CYCLE;
 545		changed++;
 546	}
 547	if (changed)
 548		queue_delayed_work(system_power_efficient_wq,
 549				&hub->leds, LED_CYCLE_PERIOD);
 550}
 551
 552/* use a short timeout for hub/port status fetches */
 553#define	USB_STS_TIMEOUT		1000
 554#define	USB_STS_RETRIES		5
 555
 556/*
 557 * USB 2.0 spec Section 11.24.2.6
 558 */
 559static int get_hub_status(struct usb_device *hdev,
 560		struct usb_hub_status *data)
 561{
 562	int i, status = -ETIMEDOUT;
 563
 564	for (i = 0; i < USB_STS_RETRIES &&
 565			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 566		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 567			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 568			data, sizeof(*data), USB_STS_TIMEOUT);
 569	}
 570	return status;
 571}
 572
 573/*
 574 * USB 2.0 spec Section 11.24.2.7
 575 * USB 3.1 takes into use the wValue and wLength fields, spec Section 10.16.2.6
 576 */
 577static int get_port_status(struct usb_device *hdev, int port1,
 578			   void *data, u16 value, u16 length)
 579{
 580	int i, status = -ETIMEDOUT;
 581
 582	for (i = 0; i < USB_STS_RETRIES &&
 583			(status == -ETIMEDOUT || status == -EPIPE); i++) {
 584		status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 585			USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, value,
 586			port1, data, length, USB_STS_TIMEOUT);
 587	}
 588	return status;
 589}
 590
 591static int hub_ext_port_status(struct usb_hub *hub, int port1, int type,
 592			       u16 *status, u16 *change, u32 *ext_status)
 593{
 594	int ret;
 595	int len = 4;
 596
 597	if (type != HUB_PORT_STATUS)
 598		len = 8;
 599
 600	mutex_lock(&hub->status_mutex);
 601	ret = get_port_status(hub->hdev, port1, &hub->status->port, type, len);
 602	if (ret < len) {
 603		if (ret != -ENODEV)
 604			dev_err(hub->intfdev,
 605				"%s failed (err = %d)\n", __func__, ret);
 606		if (ret >= 0)
 607			ret = -EIO;
 608	} else {
 609		*status = le16_to_cpu(hub->status->port.wPortStatus);
 610		*change = le16_to_cpu(hub->status->port.wPortChange);
 611		if (type != HUB_PORT_STATUS && ext_status)
 612			*ext_status = le32_to_cpu(
 613				hub->status->port.dwExtPortStatus);
 614		ret = 0;
 615	}
 616	mutex_unlock(&hub->status_mutex);
 617	return ret;
 618}
 619
 620int usb_hub_port_status(struct usb_hub *hub, int port1,
 621		u16 *status, u16 *change)
 622{
 623	return hub_ext_port_status(hub, port1, HUB_PORT_STATUS,
 624				   status, change, NULL);
 625}
 626
 627static void hub_resubmit_irq_urb(struct usb_hub *hub)
 628{
 629	unsigned long flags;
 630	int status;
 631
 632	spin_lock_irqsave(&hub->irq_urb_lock, flags);
 633
 634	if (hub->quiescing) {
 635		spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 636		return;
 637	}
 638
 639	status = usb_submit_urb(hub->urb, GFP_ATOMIC);
 640	if (status && status != -ENODEV && status != -EPERM &&
 641	    status != -ESHUTDOWN) {
 642		dev_err(hub->intfdev, "resubmit --> %d\n", status);
 643		mod_timer(&hub->irq_urb_retry, jiffies + HZ);
 644	}
 645
 646	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
 647}
 648
 649static void hub_retry_irq_urb(struct timer_list *t)
 650{
 651	struct usb_hub *hub = from_timer(hub, t, irq_urb_retry);
 652
 653	hub_resubmit_irq_urb(hub);
 654}
 655
 656
 657static void kick_hub_wq(struct usb_hub *hub)
 658{
 659	struct usb_interface *intf;
 660
 661	if (hub->disconnected || work_pending(&hub->events))
 662		return;
 663
 664	/*
 665	 * Suppress autosuspend until the event is proceed.
 666	 *
 667	 * Be careful and make sure that the symmetric operation is
 668	 * always called. We are here only when there is no pending
 669	 * work for this hub. Therefore put the interface either when
 670	 * the new work is called or when it is canceled.
 671	 */
 672	intf = to_usb_interface(hub->intfdev);
 673	usb_autopm_get_interface_no_resume(intf);
 674	kref_get(&hub->kref);
 675
 676	if (queue_work(hub_wq, &hub->events))
 677		return;
 678
 679	/* the work has already been scheduled */
 680	usb_autopm_put_interface_async(intf);
 681	kref_put(&hub->kref, hub_release);
 682}
 683
 684void usb_kick_hub_wq(struct usb_device *hdev)
 685{
 686	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
 687
 688	if (hub)
 689		kick_hub_wq(hub);
 690}
 691
 692/*
 693 * Let the USB core know that a USB 3.0 device has sent a Function Wake Device
 694 * Notification, which indicates it had initiated remote wakeup.
 695 *
 696 * USB 3.0 hubs do not report the port link state change from U3 to U0 when the
 697 * device initiates resume, so the USB core will not receive notice of the
 698 * resume through the normal hub interrupt URB.
 699 */
 700void usb_wakeup_notification(struct usb_device *hdev,
 701		unsigned int portnum)
 702{
 703	struct usb_hub *hub;
 704	struct usb_port *port_dev;
 705
 706	if (!hdev)
 707		return;
 708
 709	hub = usb_hub_to_struct_hub(hdev);
 710	if (hub) {
 711		port_dev = hub->ports[portnum - 1];
 712		if (port_dev && port_dev->child)
 713			pm_wakeup_event(&port_dev->child->dev, 0);
 714
 715		set_bit(portnum, hub->wakeup_bits);
 716		kick_hub_wq(hub);
 717	}
 718}
 719EXPORT_SYMBOL_GPL(usb_wakeup_notification);
 720
 721/* completion function, fires on port status changes and various faults */
 722static void hub_irq(struct urb *urb)
 723{
 724	struct usb_hub *hub = urb->context;
 725	int status = urb->status;
 726	unsigned i;
 727	unsigned long bits;
 728
 729	switch (status) {
 730	case -ENOENT:		/* synchronous unlink */
 731	case -ECONNRESET:	/* async unlink */
 732	case -ESHUTDOWN:	/* hardware going away */
 733		return;
 734
 735	default:		/* presumably an error */
 736		/* Cause a hub reset after 10 consecutive errors */
 737		dev_dbg(hub->intfdev, "transfer --> %d\n", status);
 738		if ((++hub->nerrors < 10) || hub->error)
 739			goto resubmit;
 740		hub->error = status;
 741		fallthrough;
 742
 743	/* let hub_wq handle things */
 744	case 0:			/* we got data:  port status changed */
 745		bits = 0;
 746		for (i = 0; i < urb->actual_length; ++i)
 747			bits |= ((unsigned long) ((*hub->buffer)[i]))
 748					<< (i*8);
 749		hub->event_bits[0] = bits;
 750		break;
 751	}
 752
 753	hub->nerrors = 0;
 754
 755	/* Something happened, let hub_wq figure it out */
 756	kick_hub_wq(hub);
 757
 758resubmit:
 759	hub_resubmit_irq_urb(hub);
 
 
 
 
 
 760}
 761
 762/* USB 2.0 spec Section 11.24.2.3 */
 763static inline int
 764hub_clear_tt_buffer(struct usb_device *hdev, u16 devinfo, u16 tt)
 765{
 766	/* Need to clear both directions for control ep */
 767	if (((devinfo >> 11) & USB_ENDPOINT_XFERTYPE_MASK) ==
 768			USB_ENDPOINT_XFER_CONTROL) {
 769		int status = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 770				HUB_CLEAR_TT_BUFFER, USB_RT_PORT,
 771				devinfo ^ 0x8000, tt, NULL, 0, 1000);
 772		if (status)
 773			return status;
 774	}
 775	return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 776			       HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 777			       tt, NULL, 0, 1000);
 778}
 779
 780/*
 781 * enumeration blocks hub_wq for a long time. we use keventd instead, since
 782 * long blocking there is the exception, not the rule.  accordingly, HCDs
 783 * talking to TTs must queue control transfers (not just bulk and iso), so
 784 * both can talk to the same hub concurrently.
 785 */
 786static void hub_tt_work(struct work_struct *work)
 787{
 788	struct usb_hub		*hub =
 789		container_of(work, struct usb_hub, tt.clear_work);
 790	unsigned long		flags;
 791
 792	spin_lock_irqsave(&hub->tt.lock, flags);
 793	while (!list_empty(&hub->tt.clear_list)) {
 794		struct list_head	*next;
 795		struct usb_tt_clear	*clear;
 796		struct usb_device	*hdev = hub->hdev;
 797		const struct hc_driver	*drv;
 798		int			status;
 799
 800		next = hub->tt.clear_list.next;
 801		clear = list_entry(next, struct usb_tt_clear, clear_list);
 802		list_del(&clear->clear_list);
 803
 804		/* drop lock so HCD can concurrently report other TT errors */
 805		spin_unlock_irqrestore(&hub->tt.lock, flags);
 806		status = hub_clear_tt_buffer(hdev, clear->devinfo, clear->tt);
 807		if (status && status != -ENODEV)
 808			dev_err(&hdev->dev,
 809				"clear tt %d (%04x) error %d\n",
 810				clear->tt, clear->devinfo, status);
 811
 812		/* Tell the HCD, even if the operation failed */
 813		drv = clear->hcd->driver;
 814		if (drv->clear_tt_buffer_complete)
 815			(drv->clear_tt_buffer_complete)(clear->hcd, clear->ep);
 816
 817		kfree(clear);
 818		spin_lock_irqsave(&hub->tt.lock, flags);
 819	}
 820	spin_unlock_irqrestore(&hub->tt.lock, flags);
 821}
 822
 823/**
 824 * usb_hub_set_port_power - control hub port's power state
 825 * @hdev: USB device belonging to the usb hub
 826 * @hub: target hub
 827 * @port1: port index
 828 * @set: expected status
 829 *
 830 * call this function to control port's power via setting or
 831 * clearing the port's PORT_POWER feature.
 832 *
 833 * Return: 0 if successful. A negative error code otherwise.
 834 */
 835int usb_hub_set_port_power(struct usb_device *hdev, struct usb_hub *hub,
 836			   int port1, bool set)
 837{
 838	int ret;
 839
 840	if (set)
 841		ret = set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 842	else
 843		ret = usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
 844
 845	if (ret)
 846		return ret;
 847
 848	if (set)
 849		set_bit(port1, hub->power_bits);
 850	else
 851		clear_bit(port1, hub->power_bits);
 852	return 0;
 853}
 854
 855/**
 856 * usb_hub_clear_tt_buffer - clear control/bulk TT state in high speed hub
 857 * @urb: an URB associated with the failed or incomplete split transaction
 858 *
 859 * High speed HCDs use this to tell the hub driver that some split control or
 860 * bulk transaction failed in a way that requires clearing internal state of
 861 * a transaction translator.  This is normally detected (and reported) from
 862 * interrupt context.
 863 *
 864 * It may not be possible for that hub to handle additional full (or low)
 865 * speed transactions until that state is fully cleared out.
 866 *
 867 * Return: 0 if successful. A negative error code otherwise.
 868 */
 869int usb_hub_clear_tt_buffer(struct urb *urb)
 870{
 871	struct usb_device	*udev = urb->dev;
 872	int			pipe = urb->pipe;
 873	struct usb_tt		*tt = udev->tt;
 874	unsigned long		flags;
 875	struct usb_tt_clear	*clear;
 876
 877	/* we've got to cope with an arbitrary number of pending TT clears,
 878	 * since each TT has "at least two" buffers that can need it (and
 879	 * there can be many TTs per hub).  even if they're uncommon.
 880	 */
 881	clear = kmalloc(sizeof *clear, GFP_ATOMIC);
 882	if (clear == NULL) {
 883		dev_err(&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 884		/* FIXME recover somehow ... RESET_TT? */
 885		return -ENOMEM;
 886	}
 887
 888	/* info that CLEAR_TT_BUFFER needs */
 889	clear->tt = tt->multi ? udev->ttport : 1;
 890	clear->devinfo = usb_pipeendpoint (pipe);
 891	clear->devinfo |= ((u16)udev->devaddr) << 4;
 892	clear->devinfo |= usb_pipecontrol(pipe)
 893			? (USB_ENDPOINT_XFER_CONTROL << 11)
 894			: (USB_ENDPOINT_XFER_BULK << 11);
 895	if (usb_pipein(pipe))
 896		clear->devinfo |= 1 << 15;
 897
 898	/* info for completion callback */
 899	clear->hcd = bus_to_hcd(udev->bus);
 900	clear->ep = urb->ep;
 901
 902	/* tell keventd to clear state for this TT */
 903	spin_lock_irqsave(&tt->lock, flags);
 904	list_add_tail(&clear->clear_list, &tt->clear_list);
 905	schedule_work(&tt->clear_work);
 906	spin_unlock_irqrestore(&tt->lock, flags);
 907	return 0;
 908}
 909EXPORT_SYMBOL_GPL(usb_hub_clear_tt_buffer);
 910
 911static void hub_power_on(struct usb_hub *hub, bool do_delay)
 912{
 913	int port1;
 914
 915	/* Enable power on each port.  Some hubs have reserved values
 916	 * of LPSM (> 2) in their descriptors, even though they are
 917	 * USB 2.0 hubs.  Some hubs do not implement port-power switching
 918	 * but only emulate it.  In all cases, the ports won't work
 919	 * unless we send these messages to the hub.
 920	 */
 921	if (hub_is_port_power_switchable(hub))
 922		dev_dbg(hub->intfdev, "enabling power on all ports\n");
 923	else
 924		dev_dbg(hub->intfdev, "trying to enable port power on "
 925				"non-switchable hub\n");
 926	for (port1 = 1; port1 <= hub->hdev->maxchild; port1++)
 927		if (test_bit(port1, hub->power_bits))
 928			set_port_feature(hub->hdev, port1, USB_PORT_FEAT_POWER);
 929		else
 930			usb_clear_port_feature(hub->hdev, port1,
 931						USB_PORT_FEAT_POWER);
 932	if (do_delay)
 933		msleep(hub_power_on_good_delay(hub));
 934}
 935
 936static int hub_hub_status(struct usb_hub *hub,
 937		u16 *status, u16 *change)
 938{
 939	int ret;
 940
 941	mutex_lock(&hub->status_mutex);
 942	ret = get_hub_status(hub->hdev, &hub->status->hub);
 943	if (ret < 0) {
 944		if (ret != -ENODEV)
 945			dev_err(hub->intfdev,
 946				"%s failed (err = %d)\n", __func__, ret);
 947	} else {
 948		*status = le16_to_cpu(hub->status->hub.wHubStatus);
 949		*change = le16_to_cpu(hub->status->hub.wHubChange);
 950		ret = 0;
 951	}
 952	mutex_unlock(&hub->status_mutex);
 953	return ret;
 954}
 955
 956static int hub_set_port_link_state(struct usb_hub *hub, int port1,
 957			unsigned int link_status)
 958{
 959	return set_port_feature(hub->hdev,
 960			port1 | (link_status << 3),
 961			USB_PORT_FEAT_LINK_STATE);
 962}
 963
 964/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 965 * Disable a port and mark a logical connect-change event, so that some
 966 * time later hub_wq will disconnect() any existing usb_device on the port
 967 * and will re-enumerate if there actually is a device attached.
 968 */
 969static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
 970{
 971	dev_dbg(&hub->ports[port1 - 1]->dev, "logical disconnect\n");
 972	hub_port_disable(hub, port1, 1);
 973
 974	/* FIXME let caller ask to power down the port:
 975	 *  - some devices won't enumerate without a VBUS power cycle
 976	 *  - SRP saves power that way
 977	 *  - ... new call, TBD ...
 978	 * That's easy if this hub can switch power per-port, and
 979	 * hub_wq reactivates the port later (timer, SRP, etc).
 980	 * Powerdown must be optional, because of reset/DFU.
 981	 */
 982
 983	set_bit(port1, hub->change_bits);
 984	kick_hub_wq(hub);
 985}
 986
 987/**
 988 * usb_remove_device - disable a device's port on its parent hub
 989 * @udev: device to be disabled and removed
 990 * Context: @udev locked, must be able to sleep.
 991 *
 992 * After @udev's port has been disabled, hub_wq is notified and it will
 993 * see that the device has been disconnected.  When the device is
 994 * physically unplugged and something is plugged in, the events will
 995 * be received and processed normally.
 996 *
 997 * Return: 0 if successful. A negative error code otherwise.
 998 */
 999int usb_remove_device(struct usb_device *udev)
1000{
1001	struct usb_hub *hub;
1002	struct usb_interface *intf;
1003	int ret;
1004
1005	if (!udev->parent)	/* Can't remove a root hub */
1006		return -EINVAL;
1007	hub = usb_hub_to_struct_hub(udev->parent);
1008	intf = to_usb_interface(hub->intfdev);
1009
1010	ret = usb_autopm_get_interface(intf);
1011	if (ret < 0)
1012		return ret;
1013
1014	set_bit(udev->portnum, hub->removed_bits);
1015	hub_port_logical_disconnect(hub, udev->portnum);
1016	usb_autopm_put_interface(intf);
1017	return 0;
1018}
1019
1020enum hub_activation_type {
1021	HUB_INIT, HUB_INIT2, HUB_INIT3,		/* INITs must come first */
1022	HUB_POST_RESET, HUB_RESUME, HUB_RESET_RESUME,
1023};
1024
1025static void hub_init_func2(struct work_struct *ws);
1026static void hub_init_func3(struct work_struct *ws);
1027
1028static void hub_activate(struct usb_hub *hub, enum hub_activation_type type)
1029{
1030	struct usb_device *hdev = hub->hdev;
1031	struct usb_hcd *hcd;
1032	int ret;
1033	int port1;
1034	int status;
1035	bool need_debounce_delay = false;
1036	unsigned delay;
1037
1038	/* Continue a partial initialization */
1039	if (type == HUB_INIT2 || type == HUB_INIT3) {
1040		device_lock(&hdev->dev);
1041
1042		/* Was the hub disconnected while we were waiting? */
1043		if (hub->disconnected)
1044			goto disconnected;
 
 
 
1045		if (type == HUB_INIT2)
1046			goto init2;
1047		goto init3;
1048	}
1049	kref_get(&hub->kref);
1050
1051	/* The superspeed hub except for root hub has to use Hub Depth
1052	 * value as an offset into the route string to locate the bits
1053	 * it uses to determine the downstream port number. So hub driver
1054	 * should send a set hub depth request to superspeed hub after
1055	 * the superspeed hub is set configuration in initialization or
1056	 * reset procedure.
1057	 *
1058	 * After a resume, port power should still be on.
1059	 * For any other type of activation, turn it on.
1060	 */
1061	if (type != HUB_RESUME) {
1062		if (hdev->parent && hub_is_superspeed(hdev)) {
1063			ret = usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
1064					HUB_SET_DEPTH, USB_RT_HUB,
1065					hdev->level - 1, 0, NULL, 0,
1066					USB_CTRL_SET_TIMEOUT);
1067			if (ret < 0)
1068				dev_err(hub->intfdev,
1069						"set hub depth failed\n");
1070		}
1071
1072		/* Speed up system boot by using a delayed_work for the
1073		 * hub's initial power-up delays.  This is pretty awkward
1074		 * and the implementation looks like a home-brewed sort of
1075		 * setjmp/longjmp, but it saves at least 100 ms for each
1076		 * root hub (assuming usbcore is compiled into the kernel
1077		 * rather than as a module).  It adds up.
1078		 *
1079		 * This can't be done for HUB_RESUME or HUB_RESET_RESUME
1080		 * because for those activation types the ports have to be
1081		 * operational when we return.  In theory this could be done
1082		 * for HUB_POST_RESET, but it's easier not to.
1083		 */
1084		if (type == HUB_INIT) {
1085			delay = hub_power_on_good_delay(hub);
1086
1087			hub_power_on(hub, false);
1088			INIT_DELAYED_WORK(&hub->init_work, hub_init_func2);
1089			queue_delayed_work(system_power_efficient_wq,
1090					&hub->init_work,
1091					msecs_to_jiffies(delay));
1092
1093			/* Suppress autosuspend until init is done */
1094			usb_autopm_get_interface_no_resume(
1095					to_usb_interface(hub->intfdev));
1096			return;		/* Continues at init2: below */
1097		} else if (type == HUB_RESET_RESUME) {
1098			/* The internal host controller state for the hub device
1099			 * may be gone after a host power loss on system resume.
1100			 * Update the device's info so the HW knows it's a hub.
1101			 */
1102			hcd = bus_to_hcd(hdev->bus);
1103			if (hcd->driver->update_hub_device) {
1104				ret = hcd->driver->update_hub_device(hcd, hdev,
1105						&hub->tt, GFP_NOIO);
1106				if (ret < 0) {
1107					dev_err(hub->intfdev,
1108						"Host not accepting hub info update\n");
1109					dev_err(hub->intfdev,
1110						"LS/FS devices and hubs may not work under this hub\n");
 
 
1111				}
1112			}
1113			hub_power_on(hub, true);
1114		} else {
1115			hub_power_on(hub, true);
1116		}
1117	/* Give some time on remote wakeup to let links to transit to U0 */
1118	} else if (hub_is_superspeed(hub->hdev))
1119		msleep(20);
1120
1121 init2:
1122
1123	/*
1124	 * Check each port and set hub->change_bits to let hub_wq know
1125	 * which ports need attention.
1126	 */
1127	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
1128		struct usb_port *port_dev = hub->ports[port1 - 1];
1129		struct usb_device *udev = port_dev->child;
1130		u16 portstatus, portchange;
1131
1132		portstatus = portchange = 0;
1133		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
1134		if (status)
1135			goto abort;
1136
1137		if (udev || (portstatus & USB_PORT_STAT_CONNECTION))
1138			dev_dbg(&port_dev->dev, "status %04x change %04x\n",
1139					portstatus, portchange);
1140
1141		/*
1142		 * After anything other than HUB_RESUME (i.e., initialization
1143		 * or any sort of reset), every port should be disabled.
1144		 * Unconnected ports should likewise be disabled (paranoia),
1145		 * and so should ports for which we have no usb_device.
1146		 */
1147		if ((portstatus & USB_PORT_STAT_ENABLE) && (
1148				type != HUB_RESUME ||
1149				!(portstatus & USB_PORT_STAT_CONNECTION) ||
1150				!udev ||
1151				udev->state == USB_STATE_NOTATTACHED)) {
1152			/*
1153			 * USB3 protocol ports will automatically transition
1154			 * to Enabled state when detect an USB3.0 device attach.
1155			 * Do not disable USB3 protocol ports, just pretend
1156			 * power was lost
1157			 */
1158			portstatus &= ~USB_PORT_STAT_ENABLE;
1159			if (!hub_is_superspeed(hdev))
1160				usb_clear_port_feature(hdev, port1,
1161						   USB_PORT_FEAT_ENABLE);
1162		}
1163
1164		/* Make sure a warm-reset request is handled by port_event */
1165		if (type == HUB_RESUME &&
1166		    hub_port_warm_reset_required(hub, port1, portstatus))
1167			set_bit(port1, hub->event_bits);
1168
1169		/*
1170		 * Add debounce if USB3 link is in polling/link training state.
1171		 * Link will automatically transition to Enabled state after
1172		 * link training completes.
1173		 */
1174		if (hub_is_superspeed(hdev) &&
1175		    ((portstatus & USB_PORT_STAT_LINK_STATE) ==
1176						USB_SS_PORT_LS_POLLING))
1177			need_debounce_delay = true;
1178
1179		/* Clear status-change flags; we'll debounce later */
1180		if (portchange & USB_PORT_STAT_C_CONNECTION) {
1181			need_debounce_delay = true;
1182			usb_clear_port_feature(hub->hdev, port1,
1183					USB_PORT_FEAT_C_CONNECTION);
1184		}
1185		if (portchange & USB_PORT_STAT_C_ENABLE) {
1186			need_debounce_delay = true;
1187			usb_clear_port_feature(hub->hdev, port1,
1188					USB_PORT_FEAT_C_ENABLE);
1189		}
1190		if (portchange & USB_PORT_STAT_C_RESET) {
1191			need_debounce_delay = true;
1192			usb_clear_port_feature(hub->hdev, port1,
1193					USB_PORT_FEAT_C_RESET);
1194		}
1195		if ((portchange & USB_PORT_STAT_C_BH_RESET) &&
1196				hub_is_superspeed(hub->hdev)) {
1197			need_debounce_delay = true;
1198			usb_clear_port_feature(hub->hdev, port1,
1199					USB_PORT_FEAT_C_BH_PORT_RESET);
1200		}
1201		/* We can forget about a "removed" device when there's a
1202		 * physical disconnect or the connect status changes.
1203		 */
1204		if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
1205				(portchange & USB_PORT_STAT_C_CONNECTION))
1206			clear_bit(port1, hub->removed_bits);
1207
1208		if (!udev || udev->state == USB_STATE_NOTATTACHED) {
1209			/* Tell hub_wq to disconnect the device or
1210			 * check for a new connection or over current condition.
1211			 * Based on USB2.0 Spec Section 11.12.5,
1212			 * C_PORT_OVER_CURRENT could be set while
1213			 * PORT_OVER_CURRENT is not. So check for any of them.
1214			 */
1215			if (udev || (portstatus & USB_PORT_STAT_CONNECTION) ||
1216			    (portchange & USB_PORT_STAT_C_CONNECTION) ||
1217			    (portstatus & USB_PORT_STAT_OVERCURRENT) ||
1218			    (portchange & USB_PORT_STAT_C_OVERCURRENT))
1219				set_bit(port1, hub->change_bits);
1220
1221		} else if (portstatus & USB_PORT_STAT_ENABLE) {
1222			bool port_resumed = (portstatus &
1223					USB_PORT_STAT_LINK_STATE) ==
1224				USB_SS_PORT_LS_U0;
1225			/* The power session apparently survived the resume.
1226			 * If there was an overcurrent or suspend change
1227			 * (i.e., remote wakeup request), have hub_wq
1228			 * take care of it.  Look at the port link state
1229			 * for USB 3.0 hubs, since they don't have a suspend
1230			 * change bit, and they don't set the port link change
1231			 * bit on device-initiated resume.
1232			 */
1233			if (portchange || (hub_is_superspeed(hub->hdev) &&
1234						port_resumed))
1235				set_bit(port1, hub->event_bits);
1236
1237		} else if (udev->persist_enabled) {
1238#ifdef CONFIG_PM
1239			udev->reset_resume = 1;
1240#endif
1241			/* Don't set the change_bits when the device
1242			 * was powered off.
1243			 */
1244			if (test_bit(port1, hub->power_bits))
1245				set_bit(port1, hub->change_bits);
1246
1247		} else {
1248			/* The power session is gone; tell hub_wq */
1249			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1250			set_bit(port1, hub->change_bits);
1251		}
1252	}
1253
1254	/* If no port-status-change flags were set, we don't need any
1255	 * debouncing.  If flags were set we can try to debounce the
1256	 * ports all at once right now, instead of letting hub_wq do them
1257	 * one at a time later on.
1258	 *
1259	 * If any port-status changes do occur during this delay, hub_wq
1260	 * will see them later and handle them normally.
1261	 */
1262	if (need_debounce_delay) {
1263		delay = HUB_DEBOUNCE_STABLE;
1264
1265		/* Don't do a long sleep inside a workqueue routine */
1266		if (type == HUB_INIT2) {
1267			INIT_DELAYED_WORK(&hub->init_work, hub_init_func3);
1268			queue_delayed_work(system_power_efficient_wq,
1269					&hub->init_work,
1270					msecs_to_jiffies(delay));
1271			device_unlock(&hdev->dev);
1272			return;		/* Continues at init3: below */
1273		} else {
1274			msleep(delay);
1275		}
1276	}
1277 init3:
1278	hub->quiescing = 0;
1279
1280	status = usb_submit_urb(hub->urb, GFP_NOIO);
1281	if (status < 0)
1282		dev_err(hub->intfdev, "activate --> %d\n", status);
1283	if (hub->has_indicators && blinkenlights)
1284		queue_delayed_work(system_power_efficient_wq,
1285				&hub->leds, LED_CYCLE_PERIOD);
1286
1287	/* Scan all ports that need attention */
1288	kick_hub_wq(hub);
1289 abort:
1290	if (type == HUB_INIT2 || type == HUB_INIT3) {
1291		/* Allow autosuspend if it was suppressed */
1292 disconnected:
1293		usb_autopm_put_interface_async(to_usb_interface(hub->intfdev));
1294		device_unlock(&hdev->dev);
1295	}
 
1296
1297	kref_put(&hub->kref, hub_release);
1298}
1299
1300/* Implement the continuations for the delays above */
1301static void hub_init_func2(struct work_struct *ws)
1302{
1303	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1304
1305	hub_activate(hub, HUB_INIT2);
1306}
1307
1308static void hub_init_func3(struct work_struct *ws)
1309{
1310	struct usb_hub *hub = container_of(ws, struct usb_hub, init_work.work);
1311
1312	hub_activate(hub, HUB_INIT3);
1313}
1314
1315enum hub_quiescing_type {
1316	HUB_DISCONNECT, HUB_PRE_RESET, HUB_SUSPEND
1317};
1318
1319static void hub_quiesce(struct usb_hub *hub, enum hub_quiescing_type type)
1320{
1321	struct usb_device *hdev = hub->hdev;
1322	unsigned long flags;
1323	int i;
1324
 
 
1325	/* hub_wq and related activity won't re-trigger */
1326	spin_lock_irqsave(&hub->irq_urb_lock, flags);
1327	hub->quiescing = 1;
1328	spin_unlock_irqrestore(&hub->irq_urb_lock, flags);
1329
1330	if (type != HUB_SUSPEND) {
1331		/* Disconnect all the children */
1332		for (i = 0; i < hdev->maxchild; ++i) {
1333			if (hub->ports[i]->child)
1334				usb_disconnect(&hub->ports[i]->child);
1335		}
1336	}
1337
1338	/* Stop hub_wq and related activity */
1339	del_timer_sync(&hub->irq_urb_retry);
1340	usb_kill_urb(hub->urb);
1341	if (hub->has_indicators)
1342		cancel_delayed_work_sync(&hub->leds);
1343	if (hub->tt.hub)
1344		flush_work(&hub->tt.clear_work);
1345}
1346
1347static void hub_pm_barrier_for_all_ports(struct usb_hub *hub)
1348{
1349	int i;
1350
1351	for (i = 0; i < hub->hdev->maxchild; ++i)
1352		pm_runtime_barrier(&hub->ports[i]->dev);
1353}
1354
1355/* caller has locked the hub device */
1356static int hub_pre_reset(struct usb_interface *intf)
1357{
1358	struct usb_hub *hub = usb_get_intfdata(intf);
1359
1360	hub_quiesce(hub, HUB_PRE_RESET);
1361	hub->in_reset = 1;
1362	hub_pm_barrier_for_all_ports(hub);
1363	return 0;
1364}
1365
1366/* caller has locked the hub device */
1367static int hub_post_reset(struct usb_interface *intf)
1368{
1369	struct usb_hub *hub = usb_get_intfdata(intf);
1370
1371	hub->in_reset = 0;
1372	hub_pm_barrier_for_all_ports(hub);
1373	hub_activate(hub, HUB_POST_RESET);
1374	return 0;
1375}
1376
1377static int hub_configure(struct usb_hub *hub,
1378	struct usb_endpoint_descriptor *endpoint)
1379{
1380	struct usb_hcd *hcd;
1381	struct usb_device *hdev = hub->hdev;
1382	struct device *hub_dev = hub->intfdev;
1383	u16 hubstatus, hubchange;
1384	u16 wHubCharacteristics;
1385	unsigned int pipe;
1386	int maxp, ret, i;
1387	char *message = "out of memory";
1388	unsigned unit_load;
1389	unsigned full_load;
1390	unsigned maxchild;
1391
1392	hub->buffer = kmalloc(sizeof(*hub->buffer), GFP_KERNEL);
1393	if (!hub->buffer) {
1394		ret = -ENOMEM;
1395		goto fail;
1396	}
1397
1398	hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
1399	if (!hub->status) {
1400		ret = -ENOMEM;
1401		goto fail;
1402	}
1403	mutex_init(&hub->status_mutex);
1404
1405	hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);
1406	if (!hub->descriptor) {
1407		ret = -ENOMEM;
1408		goto fail;
1409	}
1410
1411	/* Request the entire hub descriptor.
1412	 * hub->descriptor can handle USB_MAXCHILDREN ports,
1413	 * but a (non-SS) hub can/will return fewer bytes here.
1414	 */
1415	ret = get_hub_descriptor(hdev, hub->descriptor);
1416	if (ret < 0) {
1417		message = "can't read hub descriptor";
1418		goto fail;
1419	}
1420
1421	maxchild = USB_MAXCHILDREN;
1422	if (hub_is_superspeed(hdev))
1423		maxchild = min_t(unsigned, maxchild, USB_SS_MAXPORTS);
1424
1425	if (hub->descriptor->bNbrPorts > maxchild) {
1426		message = "hub has too many ports!";
1427		ret = -ENODEV;
1428		goto fail;
1429	} else if (hub->descriptor->bNbrPorts == 0) {
1430		message = "hub doesn't have any ports!";
1431		ret = -ENODEV;
1432		goto fail;
1433	}
1434
1435	/*
1436	 * Accumulate wHubDelay + 40ns for every hub in the tree of devices.
1437	 * The resulting value will be used for SetIsochDelay() request.
1438	 */
1439	if (hub_is_superspeed(hdev) || hub_is_superspeedplus(hdev)) {
1440		u32 delay = __le16_to_cpu(hub->descriptor->u.ss.wHubDelay);
1441
1442		if (hdev->parent)
1443			delay += hdev->parent->hub_delay;
1444
1445		delay += USB_TP_TRANSMISSION_DELAY;
1446		hdev->hub_delay = min_t(u32, delay, USB_TP_TRANSMISSION_DELAY_MAX);
1447	}
1448
1449	maxchild = hub->descriptor->bNbrPorts;
1450	dev_info(hub_dev, "%d port%s detected\n", maxchild,
1451			(maxchild == 1) ? "" : "s");
1452
1453	hub->ports = kcalloc(maxchild, sizeof(struct usb_port *), GFP_KERNEL);
1454	if (!hub->ports) {
1455		ret = -ENOMEM;
1456		goto fail;
1457	}
1458
1459	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
1460	if (hub_is_superspeed(hdev)) {
1461		unit_load = 150;
1462		full_load = 900;
1463	} else {
1464		unit_load = 100;
1465		full_load = 500;
1466	}
1467
1468	/* FIXME for USB 3.0, skip for now */
1469	if ((wHubCharacteristics & HUB_CHAR_COMPOUND) &&
1470			!(hub_is_superspeed(hdev))) {
1471		char	portstr[USB_MAXCHILDREN + 1];
1472
1473		for (i = 0; i < maxchild; i++)
1474			portstr[i] = hub->descriptor->u.hs.DeviceRemovable
1475				    [((i + 1) / 8)] & (1 << ((i + 1) % 8))
1476				? 'F' : 'R';
1477		portstr[maxchild] = 0;
1478		dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
1479	} else
1480		dev_dbg(hub_dev, "standalone hub\n");
1481
1482	switch (wHubCharacteristics & HUB_CHAR_LPSM) {
1483	case HUB_CHAR_COMMON_LPSM:
1484		dev_dbg(hub_dev, "ganged power switching\n");
1485		break;
1486	case HUB_CHAR_INDV_PORT_LPSM:
1487		dev_dbg(hub_dev, "individual port power switching\n");
1488		break;
1489	case HUB_CHAR_NO_LPSM:
1490	case HUB_CHAR_LPSM:
1491		dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
1492		break;
1493	}
1494
1495	switch (wHubCharacteristics & HUB_CHAR_OCPM) {
1496	case HUB_CHAR_COMMON_OCPM:
1497		dev_dbg(hub_dev, "global over-current protection\n");
1498		break;
1499	case HUB_CHAR_INDV_PORT_OCPM:
1500		dev_dbg(hub_dev, "individual port over-current protection\n");
1501		break;
1502	case HUB_CHAR_NO_OCPM:
1503	case HUB_CHAR_OCPM:
1504		dev_dbg(hub_dev, "no over-current protection\n");
1505		break;
1506	}
1507
1508	spin_lock_init(&hub->tt.lock);
1509	INIT_LIST_HEAD(&hub->tt.clear_list);
1510	INIT_WORK(&hub->tt.clear_work, hub_tt_work);
1511	switch (hdev->descriptor.bDeviceProtocol) {
1512	case USB_HUB_PR_FS:
1513		break;
1514	case USB_HUB_PR_HS_SINGLE_TT:
1515		dev_dbg(hub_dev, "Single TT\n");
1516		hub->tt.hub = hdev;
1517		break;
1518	case USB_HUB_PR_HS_MULTI_TT:
1519		ret = usb_set_interface(hdev, 0, 1);
1520		if (ret == 0) {
1521			dev_dbg(hub_dev, "TT per port\n");
1522			hub->tt.multi = 1;
1523		} else
1524			dev_err(hub_dev, "Using single TT (err %d)\n",
1525				ret);
1526		hub->tt.hub = hdev;
1527		break;
1528	case USB_HUB_PR_SS:
1529		/* USB 3.0 hubs don't have a TT */
1530		break;
1531	default:
1532		dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
1533			hdev->descriptor.bDeviceProtocol);
1534		break;
1535	}
1536
1537	/* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
1538	switch (wHubCharacteristics & HUB_CHAR_TTTT) {
1539	case HUB_TTTT_8_BITS:
1540		if (hdev->descriptor.bDeviceProtocol != 0) {
1541			hub->tt.think_time = 666;
1542			dev_dbg(hub_dev, "TT requires at most %d "
1543					"FS bit times (%d ns)\n",
1544				8, hub->tt.think_time);
1545		}
1546		break;
1547	case HUB_TTTT_16_BITS:
1548		hub->tt.think_time = 666 * 2;
1549		dev_dbg(hub_dev, "TT requires at most %d "
1550				"FS bit times (%d ns)\n",
1551			16, hub->tt.think_time);
1552		break;
1553	case HUB_TTTT_24_BITS:
1554		hub->tt.think_time = 666 * 3;
1555		dev_dbg(hub_dev, "TT requires at most %d "
1556				"FS bit times (%d ns)\n",
1557			24, hub->tt.think_time);
1558		break;
1559	case HUB_TTTT_32_BITS:
1560		hub->tt.think_time = 666 * 4;
1561		dev_dbg(hub_dev, "TT requires at most %d "
1562				"FS bit times (%d ns)\n",
1563			32, hub->tt.think_time);
1564		break;
1565	}
1566
1567	/* probe() zeroes hub->indicator[] */
1568	if (wHubCharacteristics & HUB_CHAR_PORTIND) {
1569		hub->has_indicators = 1;
1570		dev_dbg(hub_dev, "Port indicators are supported\n");
1571	}
1572
1573	dev_dbg(hub_dev, "power on to power good time: %dms\n",
1574		hub->descriptor->bPwrOn2PwrGood * 2);
1575
1576	/* power budgeting mostly matters with bus-powered hubs,
1577	 * and battery-powered root hubs (may provide just 8 mA).
1578	 */
1579	ret = usb_get_std_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
1580	if (ret) {
1581		message = "can't get hub status";
1582		goto fail;
1583	}
1584	hcd = bus_to_hcd(hdev->bus);
1585	if (hdev == hdev->bus->root_hub) {
1586		if (hcd->power_budget > 0)
1587			hdev->bus_mA = hcd->power_budget;
1588		else
1589			hdev->bus_mA = full_load * maxchild;
1590		if (hdev->bus_mA >= full_load)
1591			hub->mA_per_port = full_load;
1592		else {
1593			hub->mA_per_port = hdev->bus_mA;
1594			hub->limited_power = 1;
1595		}
1596	} else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
1597		int remaining = hdev->bus_mA -
1598			hub->descriptor->bHubContrCurrent;
1599
1600		dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
1601			hub->descriptor->bHubContrCurrent);
1602		hub->limited_power = 1;
1603
1604		if (remaining < maxchild * unit_load)
1605			dev_warn(hub_dev,
1606					"insufficient power available "
1607					"to use all downstream ports\n");
1608		hub->mA_per_port = unit_load;	/* 7.2.1 */
1609
1610	} else {	/* Self-powered external hub */
1611		/* FIXME: What about battery-powered external hubs that
1612		 * provide less current per port? */
1613		hub->mA_per_port = full_load;
1614	}
1615	if (hub->mA_per_port < full_load)
1616		dev_dbg(hub_dev, "%umA bus power budget for each child\n",
1617				hub->mA_per_port);
1618
1619	ret = hub_hub_status(hub, &hubstatus, &hubchange);
1620	if (ret < 0) {
1621		message = "can't get hub status";
1622		goto fail;
1623	}
1624
1625	/* local power status reports aren't always correct */
1626	if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
1627		dev_dbg(hub_dev, "local power source is %s\n",
1628			(hubstatus & HUB_STATUS_LOCAL_POWER)
1629			? "lost (inactive)" : "good");
1630
1631	if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
1632		dev_dbg(hub_dev, "%sover-current condition exists\n",
1633			(hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
1634
1635	/* set up the interrupt endpoint
1636	 * We use the EP's maxpacket size instead of (PORTS+1+7)/8
1637	 * bytes as USB2.0[11.12.3] says because some hubs are known
1638	 * to send more data (and thus cause overflow). For root hubs,
1639	 * maxpktsize is defined in hcd.c's fake endpoint descriptors
1640	 * to be big enough for at least USB_MAXCHILDREN ports. */
1641	pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
1642	maxp = usb_maxpacket(hdev, pipe);
1643
1644	if (maxp > sizeof(*hub->buffer))
1645		maxp = sizeof(*hub->buffer);
1646
1647	hub->urb = usb_alloc_urb(0, GFP_KERNEL);
1648	if (!hub->urb) {
1649		ret = -ENOMEM;
1650		goto fail;
1651	}
1652
1653	usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
1654		hub, endpoint->bInterval);
1655
1656	/* maybe cycle the hub leds */
1657	if (hub->has_indicators && blinkenlights)
1658		hub->indicator[0] = INDICATOR_CYCLE;
1659
1660	mutex_lock(&usb_port_peer_mutex);
1661	for (i = 0; i < maxchild; i++) {
1662		ret = usb_hub_create_port_device(hub, i + 1);
1663		if (ret < 0) {
1664			dev_err(hub->intfdev,
1665				"couldn't create port%d device.\n", i + 1);
1666			break;
1667		}
1668	}
1669	hdev->maxchild = i;
1670	for (i = 0; i < hdev->maxchild; i++) {
1671		struct usb_port *port_dev = hub->ports[i];
1672
1673		pm_runtime_put(&port_dev->dev);
1674	}
1675
1676	mutex_unlock(&usb_port_peer_mutex);
1677	if (ret < 0)
1678		goto fail;
1679
1680	/* Update the HCD's internal representation of this hub before hub_wq
1681	 * starts getting port status changes for devices under the hub.
1682	 */
1683	if (hcd->driver->update_hub_device) {
1684		ret = hcd->driver->update_hub_device(hcd, hdev,
1685				&hub->tt, GFP_KERNEL);
1686		if (ret < 0) {
1687			message = "can't update HCD hub info";
1688			goto fail;
1689		}
1690	}
1691
1692	usb_hub_adjust_deviceremovable(hdev, hub->descriptor);
1693
1694	hub_activate(hub, HUB_INIT);
1695	return 0;
1696
1697fail:
1698	dev_err(hub_dev, "config failed, %s (err %d)\n",
1699			message, ret);
1700	/* hub_disconnect() frees urb and descriptor */
1701	return ret;
1702}
1703
1704static void hub_release(struct kref *kref)
1705{
1706	struct usb_hub *hub = container_of(kref, struct usb_hub, kref);
1707
1708	usb_put_dev(hub->hdev);
1709	usb_put_intf(to_usb_interface(hub->intfdev));
1710	kfree(hub);
1711}
1712
1713static unsigned highspeed_hubs;
1714
1715static void hub_disconnect(struct usb_interface *intf)
1716{
1717	struct usb_hub *hub = usb_get_intfdata(intf);
1718	struct usb_device *hdev = interface_to_usbdev(intf);
1719	int port1;
1720
1721	/*
1722	 * Stop adding new hub events. We do not want to block here and thus
1723	 * will not try to remove any pending work item.
1724	 */
1725	hub->disconnected = 1;
1726
1727	/* Disconnect all children and quiesce the hub */
1728	hub->error = 0;
1729	hub_quiesce(hub, HUB_DISCONNECT);
1730
1731	mutex_lock(&usb_port_peer_mutex);
1732
1733	/* Avoid races with recursively_mark_NOTATTACHED() */
1734	spin_lock_irq(&device_state_lock);
1735	port1 = hdev->maxchild;
1736	hdev->maxchild = 0;
1737	usb_set_intfdata(intf, NULL);
1738	spin_unlock_irq(&device_state_lock);
1739
1740	for (; port1 > 0; --port1)
1741		usb_hub_remove_port_device(hub, port1);
1742
1743	mutex_unlock(&usb_port_peer_mutex);
1744
1745	if (hub->hdev->speed == USB_SPEED_HIGH)
1746		highspeed_hubs--;
1747
1748	usb_free_urb(hub->urb);
1749	kfree(hub->ports);
1750	kfree(hub->descriptor);
1751	kfree(hub->status);
1752	kfree(hub->buffer);
1753
1754	pm_suspend_ignore_children(&intf->dev, false);
1755
1756	if (hub->quirk_disable_autosuspend)
1757		usb_autopm_put_interface(intf);
1758
1759	onboard_hub_destroy_pdevs(&hub->onboard_hub_devs);
1760
1761	kref_put(&hub->kref, hub_release);
1762}
1763
1764static bool hub_descriptor_is_sane(struct usb_host_interface *desc)
1765{
1766	/* Some hubs have a subclass of 1, which AFAICT according to the */
1767	/*  specs is not defined, but it works */
1768	if (desc->desc.bInterfaceSubClass != 0 &&
1769	    desc->desc.bInterfaceSubClass != 1)
1770		return false;
1771
1772	/* Multiple endpoints? What kind of mutant ninja-hub is this? */
1773	if (desc->desc.bNumEndpoints != 1)
1774		return false;
1775
1776	/* If the first endpoint is not interrupt IN, we'd better punt! */
1777	if (!usb_endpoint_is_int_in(&desc->endpoint[0].desc))
1778		return false;
1779
1780        return true;
1781}
1782
1783static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
1784{
1785	struct usb_host_interface *desc;
 
1786	struct usb_device *hdev;
1787	struct usb_hub *hub;
1788
1789	desc = intf->cur_altsetting;
1790	hdev = interface_to_usbdev(intf);
1791
1792	/*
1793	 * Set default autosuspend delay as 0 to speedup bus suspend,
1794	 * based on the below considerations:
1795	 *
1796	 * - Unlike other drivers, the hub driver does not rely on the
1797	 *   autosuspend delay to provide enough time to handle a wakeup
1798	 *   event, and the submitted status URB is just to check future
1799	 *   change on hub downstream ports, so it is safe to do it.
1800	 *
1801	 * - The patch might cause one or more auto supend/resume for
1802	 *   below very rare devices when they are plugged into hub
1803	 *   first time:
1804	 *
1805	 *   	devices having trouble initializing, and disconnect
1806	 *   	themselves from the bus and then reconnect a second
1807	 *   	or so later
1808	 *
1809	 *   	devices just for downloading firmware, and disconnects
1810	 *   	themselves after completing it
1811	 *
1812	 *   For these quite rare devices, their drivers may change the
1813	 *   autosuspend delay of their parent hub in the probe() to one
1814	 *   appropriate value to avoid the subtle problem if someone
1815	 *   does care it.
1816	 *
1817	 * - The patch may cause one or more auto suspend/resume on
1818	 *   hub during running 'lsusb', but it is probably too
1819	 *   infrequent to worry about.
1820	 *
1821	 * - Change autosuspend delay of hub can avoid unnecessary auto
1822	 *   suspend timer for hub, also may decrease power consumption
1823	 *   of USB bus.
1824	 *
1825	 * - If user has indicated to prevent autosuspend by passing
1826	 *   usbcore.autosuspend = -1 then keep autosuspend disabled.
1827	 */
1828#ifdef CONFIG_PM
1829	if (hdev->dev.power.autosuspend_delay >= 0)
1830		pm_runtime_set_autosuspend_delay(&hdev->dev, 0);
1831#endif
1832
1833	/*
1834	 * Hubs have proper suspend/resume support, except for root hubs
1835	 * where the controller driver doesn't have bus_suspend and
1836	 * bus_resume methods.
1837	 */
1838	if (hdev->parent) {		/* normal device */
1839		usb_enable_autosuspend(hdev);
1840	} else {			/* root hub */
1841		const struct hc_driver *drv = bus_to_hcd(hdev->bus)->driver;
1842
1843		if (drv->bus_suspend && drv->bus_resume)
1844			usb_enable_autosuspend(hdev);
1845	}
1846
1847	if (hdev->level == MAX_TOPO_LEVEL) {
1848		dev_err(&intf->dev,
1849			"Unsupported bus topology: hub nested too deep\n");
1850		return -E2BIG;
1851	}
1852
1853#ifdef	CONFIG_USB_OTG_DISABLE_EXTERNAL_HUB
1854	if (hdev->parent) {
1855		dev_warn(&intf->dev, "ignoring external hub\n");
1856		return -ENODEV;
1857	}
1858#endif
1859
1860	if (!hub_descriptor_is_sane(desc)) {
 
 
 
 
1861		dev_err(&intf->dev, "bad descriptor, ignoring hub\n");
1862		return -EIO;
1863	}
1864
 
 
 
 
 
 
 
 
 
 
1865	/* We found a hub */
1866	dev_info(&intf->dev, "USB hub found\n");
1867
1868	hub = kzalloc(sizeof(*hub), GFP_KERNEL);
1869	if (!hub)
 
1870		return -ENOMEM;
 
1871
1872	kref_init(&hub->kref);
1873	hub->intfdev = &intf->dev;
1874	hub->hdev = hdev;
1875	INIT_DELAYED_WORK(&hub->leds, led_work);
1876	INIT_DELAYED_WORK(&hub->init_work, NULL);
1877	INIT_WORK(&hub->events, hub_event);
1878	INIT_LIST_HEAD(&hub->onboard_hub_devs);
1879	spin_lock_init(&hub->irq_urb_lock);
1880	timer_setup(&hub->irq_urb_retry, hub_retry_irq_urb, 0);
1881	usb_get_intf(intf);
1882	usb_get_dev(hdev);
1883
1884	usb_set_intfdata(intf, hub);
1885	intf->needs_remote_wakeup = 1;
1886	pm_suspend_ignore_children(&intf->dev, true);
1887
1888	if (hdev->speed == USB_SPEED_HIGH)
1889		highspeed_hubs++;
1890
1891	if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
1892		hub->quirk_check_port_auto_suspend = 1;
1893
1894	if (id->driver_info & HUB_QUIRK_DISABLE_AUTOSUSPEND) {
1895		hub->quirk_disable_autosuspend = 1;
1896		usb_autopm_get_interface_no_resume(intf);
1897	}
1898
1899	if (hub_configure(hub, &desc->endpoint[0].desc) >= 0) {
1900		onboard_hub_create_pdevs(hdev, &hub->onboard_hub_devs);
1901
1902		return 0;
1903	}
1904
1905	hub_disconnect(intf);
1906	return -ENODEV;
1907}
1908
1909static int
1910hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
1911{
1912	struct usb_device *hdev = interface_to_usbdev(intf);
1913	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1914
1915	/* assert ifno == 0 (part of hub spec) */
1916	switch (code) {
1917	case USBDEVFS_HUB_PORTINFO: {
1918		struct usbdevfs_hub_portinfo *info = user_data;
1919		int i;
1920
1921		spin_lock_irq(&device_state_lock);
1922		if (hdev->devnum <= 0)
1923			info->nports = 0;
1924		else {
1925			info->nports = hdev->maxchild;
1926			for (i = 0; i < info->nports; i++) {
1927				if (hub->ports[i]->child == NULL)
1928					info->port[i] = 0;
1929				else
1930					info->port[i] =
1931						hub->ports[i]->child->devnum;
1932			}
1933		}
1934		spin_unlock_irq(&device_state_lock);
1935
1936		return info->nports + 1;
1937		}
1938
1939	default:
1940		return -ENOSYS;
1941	}
1942}
1943
1944/*
1945 * Allow user programs to claim ports on a hub.  When a device is attached
1946 * to one of these "claimed" ports, the program will "own" the device.
1947 */
1948static int find_port_owner(struct usb_device *hdev, unsigned port1,
1949		struct usb_dev_state ***ppowner)
1950{
1951	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
1952
1953	if (hdev->state == USB_STATE_NOTATTACHED)
1954		return -ENODEV;
1955	if (port1 == 0 || port1 > hdev->maxchild)
1956		return -EINVAL;
1957
1958	/* Devices not managed by the hub driver
1959	 * will always have maxchild equal to 0.
1960	 */
1961	*ppowner = &(hub->ports[port1 - 1]->port_owner);
1962	return 0;
1963}
1964
1965/* In the following three functions, the caller must hold hdev's lock */
1966int usb_hub_claim_port(struct usb_device *hdev, unsigned port1,
1967		       struct usb_dev_state *owner)
1968{
1969	int rc;
1970	struct usb_dev_state **powner;
1971
1972	rc = find_port_owner(hdev, port1, &powner);
1973	if (rc)
1974		return rc;
1975	if (*powner)
1976		return -EBUSY;
1977	*powner = owner;
1978	return rc;
1979}
1980EXPORT_SYMBOL_GPL(usb_hub_claim_port);
1981
1982int usb_hub_release_port(struct usb_device *hdev, unsigned port1,
1983			 struct usb_dev_state *owner)
1984{
1985	int rc;
1986	struct usb_dev_state **powner;
1987
1988	rc = find_port_owner(hdev, port1, &powner);
1989	if (rc)
1990		return rc;
1991	if (*powner != owner)
1992		return -ENOENT;
1993	*powner = NULL;
1994	return rc;
1995}
1996EXPORT_SYMBOL_GPL(usb_hub_release_port);
1997
1998void usb_hub_release_all_ports(struct usb_device *hdev, struct usb_dev_state *owner)
1999{
2000	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
2001	int n;
2002
2003	for (n = 0; n < hdev->maxchild; n++) {
2004		if (hub->ports[n]->port_owner == owner)
2005			hub->ports[n]->port_owner = NULL;
2006	}
2007
2008}
2009
2010/* The caller must hold udev's lock */
2011bool usb_device_is_owned(struct usb_device *udev)
2012{
2013	struct usb_hub *hub;
2014
2015	if (udev->state == USB_STATE_NOTATTACHED || !udev->parent)
2016		return false;
2017	hub = usb_hub_to_struct_hub(udev->parent);
2018	return !!hub->ports[udev->portnum - 1]->port_owner;
2019}
2020
2021static void recursively_mark_NOTATTACHED(struct usb_device *udev)
2022{
2023	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2024	int i;
2025
2026	for (i = 0; i < udev->maxchild; ++i) {
2027		if (hub->ports[i]->child)
2028			recursively_mark_NOTATTACHED(hub->ports[i]->child);
2029	}
2030	if (udev->state == USB_STATE_SUSPENDED)
2031		udev->active_duration -= jiffies;
2032	udev->state = USB_STATE_NOTATTACHED;
2033}
2034
2035/**
2036 * usb_set_device_state - change a device's current state (usbcore, hcds)
2037 * @udev: pointer to device whose state should be changed
2038 * @new_state: new state value to be stored
2039 *
2040 * udev->state is _not_ fully protected by the device lock.  Although
2041 * most transitions are made only while holding the lock, the state can
2042 * can change to USB_STATE_NOTATTACHED at almost any time.  This
2043 * is so that devices can be marked as disconnected as soon as possible,
2044 * without having to wait for any semaphores to be released.  As a result,
2045 * all changes to any device's state must be protected by the
2046 * device_state_lock spinlock.
2047 *
2048 * Once a device has been added to the device tree, all changes to its state
2049 * should be made using this routine.  The state should _not_ be set directly.
2050 *
2051 * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
2052 * Otherwise udev->state is set to new_state, and if new_state is
2053 * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
2054 * to USB_STATE_NOTATTACHED.
2055 */
2056void usb_set_device_state(struct usb_device *udev,
2057		enum usb_device_state new_state)
2058{
2059	unsigned long flags;
2060	int wakeup = -1;
2061
2062	spin_lock_irqsave(&device_state_lock, flags);
2063	if (udev->state == USB_STATE_NOTATTACHED)
2064		;	/* do nothing */
2065	else if (new_state != USB_STATE_NOTATTACHED) {
2066
2067		/* root hub wakeup capabilities are managed out-of-band
2068		 * and may involve silicon errata ... ignore them here.
2069		 */
2070		if (udev->parent) {
2071			if (udev->state == USB_STATE_SUSPENDED
2072					|| new_state == USB_STATE_SUSPENDED)
2073				;	/* No change to wakeup settings */
2074			else if (new_state == USB_STATE_CONFIGURED)
2075				wakeup = (udev->quirks &
2076					USB_QUIRK_IGNORE_REMOTE_WAKEUP) ? 0 :
2077					udev->actconfig->desc.bmAttributes &
2078					USB_CONFIG_ATT_WAKEUP;
2079			else
2080				wakeup = 0;
2081		}
2082		if (udev->state == USB_STATE_SUSPENDED &&
2083			new_state != USB_STATE_SUSPENDED)
2084			udev->active_duration -= jiffies;
2085		else if (new_state == USB_STATE_SUSPENDED &&
2086				udev->state != USB_STATE_SUSPENDED)
2087			udev->active_duration += jiffies;
2088		udev->state = new_state;
2089	} else
2090		recursively_mark_NOTATTACHED(udev);
2091	spin_unlock_irqrestore(&device_state_lock, flags);
2092	if (wakeup >= 0)
2093		device_set_wakeup_capable(&udev->dev, wakeup);
2094}
2095EXPORT_SYMBOL_GPL(usb_set_device_state);
2096
2097/*
2098 * Choose a device number.
2099 *
2100 * Device numbers are used as filenames in usbfs.  On USB-1.1 and
2101 * USB-2.0 buses they are also used as device addresses, however on
2102 * USB-3.0 buses the address is assigned by the controller hardware
2103 * and it usually is not the same as the device number.
2104 *
2105 * WUSB devices are simple: they have no hubs behind, so the mapping
2106 * device <-> virtual port number becomes 1:1. Why? to simplify the
2107 * life of the device connection logic in
2108 * drivers/usb/wusbcore/devconnect.c. When we do the initial secret
2109 * handshake we need to assign a temporary address in the unauthorized
2110 * space. For simplicity we use the first virtual port number found to
2111 * be free [drivers/usb/wusbcore/devconnect.c:wusbhc_devconnect_ack()]
2112 * and that becomes it's address [X < 128] or its unauthorized address
2113 * [X | 0x80].
2114 *
2115 * We add 1 as an offset to the one-based USB-stack port number
2116 * (zero-based wusb virtual port index) for two reasons: (a) dev addr
2117 * 0 is reserved by USB for default address; (b) Linux's USB stack
2118 * uses always #1 for the root hub of the controller. So USB stack's
2119 * port #1, which is wusb virtual-port #0 has address #2.
2120 *
2121 * Devices connected under xHCI are not as simple.  The host controller
2122 * supports virtualization, so the hardware assigns device addresses and
2123 * the HCD must setup data structures before issuing a set address
2124 * command to the hardware.
2125 */
2126static void choose_devnum(struct usb_device *udev)
2127{
2128	int		devnum;
2129	struct usb_bus	*bus = udev->bus;
2130
2131	/* be safe when more hub events are proceed in parallel */
2132	mutex_lock(&bus->devnum_next_mutex);
2133	if (udev->wusb) {
2134		devnum = udev->portnum + 1;
2135		BUG_ON(test_bit(devnum, bus->devmap.devicemap));
2136	} else {
2137		/* Try to allocate the next devnum beginning at
2138		 * bus->devnum_next. */
2139		devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
2140					    bus->devnum_next);
2141		if (devnum >= 128)
2142			devnum = find_next_zero_bit(bus->devmap.devicemap,
2143						    128, 1);
2144		bus->devnum_next = (devnum >= 127 ? 1 : devnum + 1);
2145	}
2146	if (devnum < 128) {
2147		set_bit(devnum, bus->devmap.devicemap);
2148		udev->devnum = devnum;
2149	}
2150	mutex_unlock(&bus->devnum_next_mutex);
2151}
2152
2153static void release_devnum(struct usb_device *udev)
2154{
2155	if (udev->devnum > 0) {
2156		clear_bit(udev->devnum, udev->bus->devmap.devicemap);
2157		udev->devnum = -1;
2158	}
2159}
2160
2161static void update_devnum(struct usb_device *udev, int devnum)
2162{
2163	/* The address for a WUSB device is managed by wusbcore. */
2164	if (!udev->wusb)
2165		udev->devnum = devnum;
2166	if (!udev->devaddr)
2167		udev->devaddr = (u8)devnum;
2168}
2169
2170static void hub_free_dev(struct usb_device *udev)
2171{
2172	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2173
2174	/* Root hubs aren't real devices, so don't free HCD resources */
2175	if (hcd->driver->free_dev && udev->parent)
2176		hcd->driver->free_dev(hcd, udev);
2177}
2178
2179static void hub_disconnect_children(struct usb_device *udev)
2180{
2181	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
2182	int i;
2183
2184	/* Free up all the children before we remove this device */
2185	for (i = 0; i < udev->maxchild; i++) {
2186		if (hub->ports[i]->child)
2187			usb_disconnect(&hub->ports[i]->child);
2188	}
2189}
2190
2191/**
2192 * usb_disconnect - disconnect a device (usbcore-internal)
2193 * @pdev: pointer to device being disconnected
2194 *
2195 * Context: task context, might sleep
2196 *
2197 * Something got disconnected. Get rid of it and all of its children.
2198 *
2199 * If *pdev is a normal device then the parent hub must already be locked.
2200 * If *pdev is a root hub then the caller must hold the usb_bus_idr_lock,
2201 * which protects the set of root hubs as well as the list of buses.
2202 *
2203 * Only hub drivers (including virtual root hub drivers for host
2204 * controllers) should ever call this.
2205 *
2206 * This call is synchronous, and may not be used in an interrupt context.
2207 */
2208void usb_disconnect(struct usb_device **pdev)
2209{
2210	struct usb_port *port_dev = NULL;
2211	struct usb_device *udev = *pdev;
2212	struct usb_hub *hub = NULL;
2213	int port1 = 1;
2214
2215	/* mark the device as inactive, so any further urb submissions for
2216	 * this device (and any of its children) will fail immediately.
2217	 * this quiesces everything except pending urbs.
2218	 */
2219	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2220	dev_info(&udev->dev, "USB disconnect, device number %d\n",
2221			udev->devnum);
2222
2223	/*
2224	 * Ensure that the pm runtime code knows that the USB device
2225	 * is in the process of being disconnected.
2226	 */
2227	pm_runtime_barrier(&udev->dev);
2228
2229	usb_lock_device(udev);
2230
2231	hub_disconnect_children(udev);
2232
2233	/* deallocate hcd/hardware state ... nuking all pending urbs and
2234	 * cleaning up all state associated with the current configuration
2235	 * so that the hardware is now fully quiesced.
2236	 */
2237	dev_dbg(&udev->dev, "unregistering device\n");
2238	usb_disable_device(udev, 0);
2239	usb_hcd_synchronize_unlinks(udev);
2240
2241	if (udev->parent) {
2242		port1 = udev->portnum;
2243		hub = usb_hub_to_struct_hub(udev->parent);
2244		port_dev = hub->ports[port1 - 1];
2245
2246		sysfs_remove_link(&udev->dev.kobj, "port");
2247		sysfs_remove_link(&port_dev->dev.kobj, "device");
2248
2249		/*
2250		 * As usb_port_runtime_resume() de-references udev, make
2251		 * sure no resumes occur during removal
2252		 */
2253		if (!test_and_set_bit(port1, hub->child_usage_bits))
2254			pm_runtime_get_sync(&port_dev->dev);
2255	}
2256
2257	usb_remove_ep_devs(&udev->ep0);
2258	usb_unlock_device(udev);
2259
2260	/* Unregister the device.  The device driver is responsible
2261	 * for de-configuring the device and invoking the remove-device
2262	 * notifier chain (used by usbfs and possibly others).
2263	 */
2264	device_del(&udev->dev);
2265
2266	/* Free the device number and delete the parent's children[]
2267	 * (or root_hub) pointer.
2268	 */
2269	release_devnum(udev);
2270
2271	/* Avoid races with recursively_mark_NOTATTACHED() */
2272	spin_lock_irq(&device_state_lock);
2273	*pdev = NULL;
2274	spin_unlock_irq(&device_state_lock);
2275
2276	if (port_dev && test_and_clear_bit(port1, hub->child_usage_bits))
2277		pm_runtime_put(&port_dev->dev);
2278
2279	hub_free_dev(udev);
2280
2281	put_device(&udev->dev);
2282}
2283
2284#ifdef CONFIG_USB_ANNOUNCE_NEW_DEVICES
2285static void show_string(struct usb_device *udev, char *id, char *string)
2286{
2287	if (!string)
2288		return;
2289	dev_info(&udev->dev, "%s: %s\n", id, string);
2290}
2291
2292static void announce_device(struct usb_device *udev)
2293{
2294	u16 bcdDevice = le16_to_cpu(udev->descriptor.bcdDevice);
2295
2296	dev_info(&udev->dev,
2297		"New USB device found, idVendor=%04x, idProduct=%04x, bcdDevice=%2x.%02x\n",
2298		le16_to_cpu(udev->descriptor.idVendor),
2299		le16_to_cpu(udev->descriptor.idProduct),
2300		bcdDevice >> 8, bcdDevice & 0xff);
2301	dev_info(&udev->dev,
2302		"New USB device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
2303		udev->descriptor.iManufacturer,
2304		udev->descriptor.iProduct,
2305		udev->descriptor.iSerialNumber);
2306	show_string(udev, "Product", udev->product);
2307	show_string(udev, "Manufacturer", udev->manufacturer);
2308	show_string(udev, "SerialNumber", udev->serial);
2309}
2310#else
2311static inline void announce_device(struct usb_device *udev) { }
2312#endif
2313
2314
2315/**
2316 * usb_enumerate_device_otg - FIXME (usbcore-internal)
2317 * @udev: newly addressed device (in ADDRESS state)
2318 *
2319 * Finish enumeration for On-The-Go devices
2320 *
2321 * Return: 0 if successful. A negative error code otherwise.
2322 */
2323static int usb_enumerate_device_otg(struct usb_device *udev)
2324{
2325	int err = 0;
2326
2327#ifdef	CONFIG_USB_OTG
2328	/*
2329	 * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
2330	 * to wake us after we've powered off VBUS; and HNP, switching roles
2331	 * "host" to "peripheral".  The OTG descriptor helps figure this out.
2332	 */
2333	if (!udev->bus->is_b_host
2334			&& udev->config
2335			&& udev->parent == udev->bus->root_hub) {
2336		struct usb_otg_descriptor	*desc = NULL;
2337		struct usb_bus			*bus = udev->bus;
2338		unsigned			port1 = udev->portnum;
2339
2340		/* descriptor may appear anywhere in config */
2341		err = __usb_get_extra_descriptor(udev->rawdescriptors[0],
2342				le16_to_cpu(udev->config[0].desc.wTotalLength),
2343				USB_DT_OTG, (void **) &desc, sizeof(*desc));
2344		if (err || !(desc->bmAttributes & USB_OTG_HNP))
2345			return 0;
2346
2347		dev_info(&udev->dev, "Dual-Role OTG device on %sHNP port\n",
2348					(port1 == bus->otg_port) ? "" : "non-");
2349
2350		/* enable HNP before suspend, it's simpler */
2351		if (port1 == bus->otg_port) {
2352			bus->b_hnp_enable = 1;
2353			err = usb_control_msg(udev,
2354				usb_sndctrlpipe(udev, 0),
2355				USB_REQ_SET_FEATURE, 0,
2356				USB_DEVICE_B_HNP_ENABLE,
2357				0, NULL, 0,
2358				USB_CTRL_SET_TIMEOUT);
2359			if (err < 0) {
2360				/*
2361				 * OTG MESSAGE: report errors here,
2362				 * customize to match your product.
2363				 */
2364				dev_err(&udev->dev, "can't set HNP mode: %d\n",
2365									err);
2366				bus->b_hnp_enable = 0;
2367			}
2368		} else if (desc->bLength == sizeof
2369				(struct usb_otg_descriptor)) {
2370			/* Set a_alt_hnp_support for legacy otg device */
2371			err = usb_control_msg(udev,
2372				usb_sndctrlpipe(udev, 0),
2373				USB_REQ_SET_FEATURE, 0,
2374				USB_DEVICE_A_ALT_HNP_SUPPORT,
2375				0, NULL, 0,
2376				USB_CTRL_SET_TIMEOUT);
2377			if (err < 0)
2378				dev_err(&udev->dev,
2379					"set a_alt_hnp_support failed: %d\n",
2380					err);
2381		}
2382	}
2383#endif
2384	return err;
2385}
2386
2387
2388/**
2389 * usb_enumerate_device - Read device configs/intfs/otg (usbcore-internal)
2390 * @udev: newly addressed device (in ADDRESS state)
2391 *
2392 * This is only called by usb_new_device() and usb_authorize_device()
2393 * and FIXME -- all comments that apply to them apply here wrt to
2394 * environment.
2395 *
2396 * If the device is WUSB and not authorized, we don't attempt to read
2397 * the string descriptors, as they will be errored out by the device
2398 * until it has been authorized.
2399 *
2400 * Return: 0 if successful. A negative error code otherwise.
2401 */
2402static int usb_enumerate_device(struct usb_device *udev)
2403{
2404	int err;
2405	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
2406
2407	if (udev->config == NULL) {
2408		err = usb_get_configuration(udev);
2409		if (err < 0) {
2410			if (err != -ENODEV)
2411				dev_err(&udev->dev, "can't read configurations, error %d\n",
2412						err);
2413			return err;
2414		}
2415	}
2416
2417	/* read the standard strings and cache them if present */
2418	udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
2419	udev->manufacturer = usb_cache_string(udev,
2420					      udev->descriptor.iManufacturer);
2421	udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
2422
2423	err = usb_enumerate_device_otg(udev);
2424	if (err < 0)
2425		return err;
2426
2427	if (IS_ENABLED(CONFIG_USB_OTG_PRODUCTLIST) && hcd->tpl_support &&
2428		!is_targeted(udev)) {
2429		/* Maybe it can talk to us, though we can't talk to it.
2430		 * (Includes HNP test device.)
2431		 */
2432		if (IS_ENABLED(CONFIG_USB_OTG) && (udev->bus->b_hnp_enable
2433			|| udev->bus->is_b_host)) {
2434			err = usb_port_suspend(udev, PMSG_AUTO_SUSPEND);
2435			if (err < 0)
2436				dev_dbg(&udev->dev, "HNP fail, %d\n", err);
2437		}
2438		return -ENOTSUPP;
2439	}
2440
2441	usb_detect_interface_quirks(udev);
2442
2443	return 0;
2444}
2445
2446static void set_usb_port_removable(struct usb_device *udev)
2447{
2448	struct usb_device *hdev = udev->parent;
2449	struct usb_hub *hub;
2450	u8 port = udev->portnum;
2451	u16 wHubCharacteristics;
2452	bool removable = true;
2453
2454	dev_set_removable(&udev->dev, DEVICE_REMOVABLE_UNKNOWN);
2455
2456	if (!hdev)
2457		return;
2458
2459	hub = usb_hub_to_struct_hub(udev->parent);
2460
2461	/*
2462	 * If the platform firmware has provided information about a port,
2463	 * use that to determine whether it's removable.
2464	 */
2465	switch (hub->ports[udev->portnum - 1]->connect_type) {
2466	case USB_PORT_CONNECT_TYPE_HOT_PLUG:
2467		dev_set_removable(&udev->dev, DEVICE_REMOVABLE);
2468		return;
2469	case USB_PORT_CONNECT_TYPE_HARD_WIRED:
2470	case USB_PORT_NOT_USED:
2471		dev_set_removable(&udev->dev, DEVICE_FIXED);
2472		return;
2473	default:
2474		break;
2475	}
2476
2477	/*
2478	 * Otherwise, check whether the hub knows whether a port is removable
2479	 * or not
2480	 */
2481	wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2482
2483	if (!(wHubCharacteristics & HUB_CHAR_COMPOUND))
2484		return;
2485
2486	if (hub_is_superspeed(hdev)) {
2487		if (le16_to_cpu(hub->descriptor->u.ss.DeviceRemovable)
2488				& (1 << port))
2489			removable = false;
2490	} else {
2491		if (hub->descriptor->u.hs.DeviceRemovable[port / 8] & (1 << (port % 8)))
2492			removable = false;
2493	}
2494
2495	if (removable)
2496		dev_set_removable(&udev->dev, DEVICE_REMOVABLE);
2497	else
2498		dev_set_removable(&udev->dev, DEVICE_FIXED);
2499
2500}
2501
2502/**
2503 * usb_new_device - perform initial device setup (usbcore-internal)
2504 * @udev: newly addressed device (in ADDRESS state)
2505 *
2506 * This is called with devices which have been detected but not fully
2507 * enumerated.  The device descriptor is available, but not descriptors
2508 * for any device configuration.  The caller must have locked either
2509 * the parent hub (if udev is a normal device) or else the
2510 * usb_bus_idr_lock (if udev is a root hub).  The parent's pointer to
2511 * udev has already been installed, but udev is not yet visible through
2512 * sysfs or other filesystem code.
2513 *
2514 * This call is synchronous, and may not be used in an interrupt context.
2515 *
2516 * Only the hub driver or root-hub registrar should ever call this.
2517 *
2518 * Return: Whether the device is configured properly or not. Zero if the
2519 * interface was registered with the driver core; else a negative errno
2520 * value.
2521 *
2522 */
2523int usb_new_device(struct usb_device *udev)
2524{
2525	int err;
2526
2527	if (udev->parent) {
2528		/* Initialize non-root-hub device wakeup to disabled;
2529		 * device (un)configuration controls wakeup capable
2530		 * sysfs power/wakeup controls wakeup enabled/disabled
2531		 */
2532		device_init_wakeup(&udev->dev, 0);
2533	}
2534
2535	/* Tell the runtime-PM framework the device is active */
2536	pm_runtime_set_active(&udev->dev);
2537	pm_runtime_get_noresume(&udev->dev);
2538	pm_runtime_use_autosuspend(&udev->dev);
2539	pm_runtime_enable(&udev->dev);
2540
2541	/* By default, forbid autosuspend for all devices.  It will be
2542	 * allowed for hubs during binding.
2543	 */
2544	usb_disable_autosuspend(udev);
2545
2546	err = usb_enumerate_device(udev);	/* Read descriptors */
2547	if (err < 0)
2548		goto fail;
2549	dev_dbg(&udev->dev, "udev %d, busnum %d, minor = %d\n",
2550			udev->devnum, udev->bus->busnum,
2551			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2552	/* export the usbdev device-node for libusb */
2553	udev->dev.devt = MKDEV(USB_DEVICE_MAJOR,
2554			(((udev->bus->busnum-1) * 128) + (udev->devnum-1)));
2555
2556	/* Tell the world! */
2557	announce_device(udev);
2558
2559	if (udev->serial)
2560		add_device_randomness(udev->serial, strlen(udev->serial));
2561	if (udev->product)
2562		add_device_randomness(udev->product, strlen(udev->product));
2563	if (udev->manufacturer)
2564		add_device_randomness(udev->manufacturer,
2565				      strlen(udev->manufacturer));
2566
2567	device_enable_async_suspend(&udev->dev);
2568
2569	/* check whether the hub or firmware marks this port as non-removable */
2570	set_usb_port_removable(udev);
 
2571
2572	/* Register the device.  The device driver is responsible
2573	 * for configuring the device and invoking the add-device
2574	 * notifier chain (used by usbfs and possibly others).
2575	 */
2576	err = device_add(&udev->dev);
2577	if (err) {
2578		dev_err(&udev->dev, "can't device_add, error %d\n", err);
2579		goto fail;
2580	}
2581
2582	/* Create link files between child device and usb port device. */
2583	if (udev->parent) {
2584		struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
2585		int port1 = udev->portnum;
2586		struct usb_port	*port_dev = hub->ports[port1 - 1];
2587
2588		err = sysfs_create_link(&udev->dev.kobj,
2589				&port_dev->dev.kobj, "port");
2590		if (err)
2591			goto fail;
2592
2593		err = sysfs_create_link(&port_dev->dev.kobj,
2594				&udev->dev.kobj, "device");
2595		if (err) {
2596			sysfs_remove_link(&udev->dev.kobj, "port");
2597			goto fail;
2598		}
2599
2600		if (!test_and_set_bit(port1, hub->child_usage_bits))
2601			pm_runtime_get_sync(&port_dev->dev);
2602	}
2603
2604	(void) usb_create_ep_devs(&udev->dev, &udev->ep0, udev);
2605	usb_mark_last_busy(udev);
2606	pm_runtime_put_sync_autosuspend(&udev->dev);
2607	return err;
2608
2609fail:
2610	usb_set_device_state(udev, USB_STATE_NOTATTACHED);
2611	pm_runtime_disable(&udev->dev);
2612	pm_runtime_set_suspended(&udev->dev);
2613	return err;
2614}
2615
2616
2617/**
2618 * usb_deauthorize_device - deauthorize a device (usbcore-internal)
2619 * @usb_dev: USB device
2620 *
2621 * Move the USB device to a very basic state where interfaces are disabled
2622 * and the device is in fact unconfigured and unusable.
2623 *
2624 * We share a lock (that we have) with device_del(), so we need to
2625 * defer its call.
2626 *
2627 * Return: 0.
2628 */
2629int usb_deauthorize_device(struct usb_device *usb_dev)
2630{
2631	usb_lock_device(usb_dev);
2632	if (usb_dev->authorized == 0)
2633		goto out_unauthorized;
2634
2635	usb_dev->authorized = 0;
2636	usb_set_configuration(usb_dev, -1);
2637
2638out_unauthorized:
2639	usb_unlock_device(usb_dev);
2640	return 0;
2641}
2642
2643
2644int usb_authorize_device(struct usb_device *usb_dev)
2645{
2646	int result = 0, c;
2647
2648	usb_lock_device(usb_dev);
2649	if (usb_dev->authorized == 1)
2650		goto out_authorized;
2651
2652	result = usb_autoresume_device(usb_dev);
2653	if (result < 0) {
2654		dev_err(&usb_dev->dev,
2655			"can't autoresume for authorization: %d\n", result);
2656		goto error_autoresume;
2657	}
2658
2659	if (usb_dev->wusb) {
2660		result = usb_get_device_descriptor(usb_dev, sizeof(usb_dev->descriptor));
2661		if (result < 0) {
2662			dev_err(&usb_dev->dev, "can't re-read device descriptor for "
2663				"authorization: %d\n", result);
2664			goto error_device_descriptor;
2665		}
2666	}
2667
2668	usb_dev->authorized = 1;
2669	/* Choose and set the configuration.  This registers the interfaces
2670	 * with the driver core and lets interface drivers bind to them.
2671	 */
2672	c = usb_choose_configuration(usb_dev);
2673	if (c >= 0) {
2674		result = usb_set_configuration(usb_dev, c);
2675		if (result) {
2676			dev_err(&usb_dev->dev,
2677				"can't set config #%d, error %d\n", c, result);
2678			/* This need not be fatal.  The user can try to
2679			 * set other configurations. */
2680		}
2681	}
2682	dev_info(&usb_dev->dev, "authorized to connect\n");
2683
2684error_device_descriptor:
2685	usb_autosuspend_device(usb_dev);
2686error_autoresume:
2687out_authorized:
2688	usb_unlock_device(usb_dev);	/* complements locktree */
2689	return result;
2690}
2691
2692/**
2693 * get_port_ssp_rate - Match the extended port status to SSP rate
2694 * @hdev: The hub device
2695 * @ext_portstatus: extended port status
2696 *
2697 * Match the extended port status speed id to the SuperSpeed Plus sublink speed
2698 * capability attributes. Base on the number of connected lanes and speed,
2699 * return the corresponding enum usb_ssp_rate.
2700 */
2701static enum usb_ssp_rate get_port_ssp_rate(struct usb_device *hdev,
2702					   u32 ext_portstatus)
2703{
2704	struct usb_ssp_cap_descriptor *ssp_cap = hdev->bos->ssp_cap;
2705	u32 attr;
2706	u8 speed_id;
2707	u8 ssac;
2708	u8 lanes;
2709	int i;
 
2710
2711	if (!ssp_cap)
2712		goto out;
2713
2714	speed_id = ext_portstatus & USB_EXT_PORT_STAT_RX_SPEED_ID;
2715	lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2716
2717	ssac = le32_to_cpu(ssp_cap->bmAttributes) &
2718		USB_SSP_SUBLINK_SPEED_ATTRIBS;
2719
2720	for (i = 0; i <= ssac; i++) {
2721		u8 ssid;
2722
2723		attr = le32_to_cpu(ssp_cap->bmSublinkSpeedAttr[i]);
2724		ssid = FIELD_GET(USB_SSP_SUBLINK_SPEED_SSID, attr);
2725		if (speed_id == ssid) {
2726			u16 mantissa;
2727			u8 lse;
2728			u8 type;
2729
2730			/*
2731			 * Note: currently asymmetric lane types are only
2732			 * applicable for SSIC operate in SuperSpeed protocol
2733			 */
2734			type = FIELD_GET(USB_SSP_SUBLINK_SPEED_ST, attr);
2735			if (type == USB_SSP_SUBLINK_SPEED_ST_ASYM_RX ||
2736			    type == USB_SSP_SUBLINK_SPEED_ST_ASYM_TX)
2737				goto out;
2738
2739			if (FIELD_GET(USB_SSP_SUBLINK_SPEED_LP, attr) !=
2740			    USB_SSP_SUBLINK_SPEED_LP_SSP)
2741				goto out;
2742
2743			lse = FIELD_GET(USB_SSP_SUBLINK_SPEED_LSE, attr);
2744			mantissa = FIELD_GET(USB_SSP_SUBLINK_SPEED_LSM, attr);
2745
2746			/* Convert to Gbps */
2747			for (; lse < USB_SSP_SUBLINK_SPEED_LSE_GBPS; lse++)
2748				mantissa /= 1000;
2749
2750			if (mantissa >= 10 && lanes == 1)
2751				return USB_SSP_GEN_2x1;
2752
2753			if (mantissa >= 10 && lanes == 2)
2754				return USB_SSP_GEN_2x2;
2755
2756			if (mantissa >= 5 && lanes == 2)
2757				return USB_SSP_GEN_1x2;
2758
2759			goto out;
2760		}
2761	}
2762
2763out:
2764	return USB_SSP_GEN_UNKNOWN;
2765}
2766
2767/* Returns 1 if @hub is a WUSB root hub, 0 otherwise */
2768static unsigned hub_is_wusb(struct usb_hub *hub)
2769{
2770	struct usb_hcd *hcd;
2771	if (hub->hdev->parent != NULL)  /* not a root hub? */
2772		return 0;
2773	hcd = bus_to_hcd(hub->hdev->bus);
2774	return hcd->wireless;
2775}
2776
2777
2778#ifdef CONFIG_USB_FEW_INIT_RETRIES
2779#define PORT_RESET_TRIES	2
2780#define SET_ADDRESS_TRIES	1
2781#define GET_DESCRIPTOR_TRIES	1
2782#define GET_MAXPACKET0_TRIES	1
2783#define PORT_INIT_TRIES		4
2784
2785#else
2786#define PORT_RESET_TRIES	5
2787#define SET_ADDRESS_TRIES	2
2788#define GET_DESCRIPTOR_TRIES	2
2789#define GET_MAXPACKET0_TRIES	3
2790#define PORT_INIT_TRIES		4
2791#endif	/* CONFIG_USB_FEW_INIT_RETRIES */
2792
2793#define DETECT_DISCONNECT_TRIES 5
2794
2795#define HUB_ROOT_RESET_TIME	60	/* times are in msec */
2796#define HUB_SHORT_RESET_TIME	10
2797#define HUB_BH_RESET_TIME	50
2798#define HUB_LONG_RESET_TIME	200
2799#define HUB_RESET_TIMEOUT	800
2800
2801static bool use_new_scheme(struct usb_device *udev, int retry,
2802			   struct usb_port *port_dev)
 
 
 
 
 
 
2803{
2804	int old_scheme_first_port =
2805		(port_dev->quirks & USB_PORT_QUIRK_OLD_SCHEME) ||
2806		old_scheme_first;
2807
2808	/*
2809	 * "New scheme" enumeration causes an extra state transition to be
2810	 * exposed to an xhci host and causes USB3 devices to receive control
2811	 * commands in the default state.  This has been seen to cause
2812	 * enumeration failures, so disable this enumeration scheme for USB3
2813	 * devices.
2814	 */
2815	if (udev->speed >= USB_SPEED_SUPER)
2816		return false;
2817
2818	/*
2819	 * If use_both_schemes is set, use the first scheme (whichever
2820	 * it is) for the larger half of the retries, then use the other
2821	 * scheme.  Otherwise, use the first scheme for all the retries.
2822	 */
2823	if (use_both_schemes && retry >= (PORT_INIT_TRIES + 1) / 2)
2824		return old_scheme_first_port;	/* Second half */
2825	return !old_scheme_first_port;		/* First half or all */
2826}
2827
2828/* Is a USB 3.0 port in the Inactive or Compliance Mode state?
2829 * Port warm reset is required to recover
2830 */
2831static bool hub_port_warm_reset_required(struct usb_hub *hub, int port1,
2832		u16 portstatus)
2833{
2834	u16 link_state;
2835
2836	if (!hub_is_superspeed(hub->hdev))
2837		return false;
2838
2839	if (test_bit(port1, hub->warm_reset_bits))
2840		return true;
2841
2842	link_state = portstatus & USB_PORT_STAT_LINK_STATE;
2843	return link_state == USB_SS_PORT_LS_SS_INACTIVE
2844		|| link_state == USB_SS_PORT_LS_COMP_MOD;
2845}
2846
2847static int hub_port_wait_reset(struct usb_hub *hub, int port1,
2848			struct usb_device *udev, unsigned int delay, bool warm)
2849{
2850	int delay_time, ret;
2851	u16 portstatus;
2852	u16 portchange;
2853	u32 ext_portstatus = 0;
2854
2855	for (delay_time = 0;
2856			delay_time < HUB_RESET_TIMEOUT;
2857			delay_time += delay) {
2858		/* wait to give the device a chance to reset */
2859		msleep(delay);
2860
2861		/* read and decode port status */
2862		if (hub_is_superspeedplus(hub->hdev))
2863			ret = hub_ext_port_status(hub, port1,
2864						  HUB_EXT_PORT_STATUS,
2865						  &portstatus, &portchange,
2866						  &ext_portstatus);
2867		else
2868			ret = usb_hub_port_status(hub, port1, &portstatus,
2869					      &portchange);
2870		if (ret < 0)
2871			return ret;
2872
2873		/*
2874		 * The port state is unknown until the reset completes.
2875		 *
2876		 * On top of that, some chips may require additional time
2877		 * to re-establish a connection after the reset is complete,
2878		 * so also wait for the connection to be re-established.
2879		 */
2880		if (!(portstatus & USB_PORT_STAT_RESET) &&
2881		    (portstatus & USB_PORT_STAT_CONNECTION))
2882			break;
2883
2884		/* switch to the long delay after two short delay failures */
2885		if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
2886			delay = HUB_LONG_RESET_TIME;
2887
2888		dev_dbg(&hub->ports[port1 - 1]->dev,
2889				"not %sreset yet, waiting %dms\n",
2890				warm ? "warm " : "", delay);
2891	}
2892
2893	if ((portstatus & USB_PORT_STAT_RESET))
2894		return -EBUSY;
2895
2896	if (hub_port_warm_reset_required(hub, port1, portstatus))
2897		return -ENOTCONN;
2898
2899	/* Device went away? */
2900	if (!(portstatus & USB_PORT_STAT_CONNECTION))
2901		return -ENOTCONN;
2902
2903	/* Retry if connect change is set but status is still connected.
2904	 * A USB 3.0 connection may bounce if multiple warm resets were issued,
2905	 * but the device may have successfully re-connected. Ignore it.
2906	 */
2907	if (!hub_is_superspeed(hub->hdev) &&
2908	    (portchange & USB_PORT_STAT_C_CONNECTION)) {
2909		usb_clear_port_feature(hub->hdev, port1,
2910				       USB_PORT_FEAT_C_CONNECTION);
2911		return -EAGAIN;
2912	}
2913
2914	if (!(portstatus & USB_PORT_STAT_ENABLE))
2915		return -EBUSY;
2916
2917	if (!udev)
2918		return 0;
2919
2920	if (hub_is_superspeedplus(hub->hdev)) {
2921		/* extended portstatus Rx and Tx lane count are zero based */
2922		udev->rx_lanes = USB_EXT_PORT_RX_LANES(ext_portstatus) + 1;
2923		udev->tx_lanes = USB_EXT_PORT_TX_LANES(ext_portstatus) + 1;
2924		udev->ssp_rate = get_port_ssp_rate(hub->hdev, ext_portstatus);
2925	} else {
2926		udev->rx_lanes = 1;
2927		udev->tx_lanes = 1;
2928		udev->ssp_rate = USB_SSP_GEN_UNKNOWN;
2929	}
2930	if (hub_is_wusb(hub))
2931		udev->speed = USB_SPEED_WIRELESS;
2932	else if (udev->ssp_rate != USB_SSP_GEN_UNKNOWN)
 
 
2933		udev->speed = USB_SPEED_SUPER_PLUS;
2934	else if (hub_is_superspeed(hub->hdev))
2935		udev->speed = USB_SPEED_SUPER;
2936	else if (portstatus & USB_PORT_STAT_HIGH_SPEED)
2937		udev->speed = USB_SPEED_HIGH;
2938	else if (portstatus & USB_PORT_STAT_LOW_SPEED)
2939		udev->speed = USB_SPEED_LOW;
2940	else
2941		udev->speed = USB_SPEED_FULL;
2942	return 0;
2943}
2944
2945/* Handle port reset and port warm(BH) reset (for USB3 protocol ports) */
2946static int hub_port_reset(struct usb_hub *hub, int port1,
2947			struct usb_device *udev, unsigned int delay, bool warm)
2948{
2949	int i, status;
2950	u16 portchange, portstatus;
2951	struct usb_port *port_dev = hub->ports[port1 - 1];
2952	int reset_recovery_time;
2953
2954	if (!hub_is_superspeed(hub->hdev)) {
2955		if (warm) {
2956			dev_err(hub->intfdev, "only USB3 hub support "
2957						"warm reset\n");
2958			return -EINVAL;
2959		}
2960		/* Block EHCI CF initialization during the port reset.
2961		 * Some companion controllers don't like it when they mix.
2962		 */
2963		down_read(&ehci_cf_port_reset_rwsem);
2964	} else if (!warm) {
2965		/*
2966		 * If the caller hasn't explicitly requested a warm reset,
2967		 * double check and see if one is needed.
2968		 */
2969		if (usb_hub_port_status(hub, port1, &portstatus,
2970					&portchange) == 0)
2971			if (hub_port_warm_reset_required(hub, port1,
2972							portstatus))
2973				warm = true;
2974	}
2975	clear_bit(port1, hub->warm_reset_bits);
2976
2977	/* Reset the port */
2978	for (i = 0; i < PORT_RESET_TRIES; i++) {
2979		status = set_port_feature(hub->hdev, port1, (warm ?
2980					USB_PORT_FEAT_BH_PORT_RESET :
2981					USB_PORT_FEAT_RESET));
2982		if (status == -ENODEV) {
2983			;	/* The hub is gone */
2984		} else if (status) {
2985			dev_err(&port_dev->dev,
2986					"cannot %sreset (err = %d)\n",
2987					warm ? "warm " : "", status);
2988		} else {
2989			status = hub_port_wait_reset(hub, port1, udev, delay,
2990								warm);
2991			if (status && status != -ENOTCONN && status != -ENODEV)
2992				dev_dbg(hub->intfdev,
2993						"port_wait_reset: err = %d\n",
2994						status);
2995		}
2996
2997		/*
2998		 * Check for disconnect or reset, and bail out after several
2999		 * reset attempts to avoid warm reset loop.
3000		 */
3001		if (status == 0 || status == -ENOTCONN || status == -ENODEV ||
3002		    (status == -EBUSY && i == PORT_RESET_TRIES - 1)) {
3003			usb_clear_port_feature(hub->hdev, port1,
3004					USB_PORT_FEAT_C_RESET);
3005
3006			if (!hub_is_superspeed(hub->hdev))
3007				goto done;
3008
3009			usb_clear_port_feature(hub->hdev, port1,
3010					USB_PORT_FEAT_C_BH_PORT_RESET);
3011			usb_clear_port_feature(hub->hdev, port1,
3012					USB_PORT_FEAT_C_PORT_LINK_STATE);
3013
3014			if (udev)
3015				usb_clear_port_feature(hub->hdev, port1,
3016					USB_PORT_FEAT_C_CONNECTION);
3017
3018			/*
3019			 * If a USB 3.0 device migrates from reset to an error
3020			 * state, re-issue the warm reset.
3021			 */
3022			if (usb_hub_port_status(hub, port1,
3023					&portstatus, &portchange) < 0)
3024				goto done;
3025
3026			if (!hub_port_warm_reset_required(hub, port1,
3027					portstatus))
3028				goto done;
3029
3030			/*
3031			 * If the port is in SS.Inactive or Compliance Mode, the
3032			 * hot or warm reset failed.  Try another warm reset.
3033			 */
3034			if (!warm) {
3035				dev_dbg(&port_dev->dev,
3036						"hot reset failed, warm reset\n");
3037				warm = true;
3038			}
3039		}
3040
3041		dev_dbg(&port_dev->dev,
3042				"not enabled, trying %sreset again...\n",
3043				warm ? "warm " : "");
3044		delay = HUB_LONG_RESET_TIME;
3045	}
3046
3047	dev_err(&port_dev->dev, "Cannot enable. Maybe the USB cable is bad?\n");
3048
3049done:
3050	if (status == 0) {
3051		if (port_dev->quirks & USB_PORT_QUIRK_FAST_ENUM)
3052			usleep_range(10000, 12000);
3053		else {
3054			/* TRSTRCY = 10 ms; plus some extra */
3055			reset_recovery_time = 10 + 40;
3056
3057			/* Hub needs extra delay after resetting its port. */
3058			if (hub->hdev->quirks & USB_QUIRK_HUB_SLOW_RESET)
3059				reset_recovery_time += 100;
3060
3061			msleep(reset_recovery_time);
3062		}
3063
3064		if (udev) {
3065			struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3066
3067			update_devnum(udev, 0);
3068			/* The xHC may think the device is already reset,
3069			 * so ignore the status.
3070			 */
3071			if (hcd->driver->reset_device)
3072				hcd->driver->reset_device(hcd, udev);
3073
3074			usb_set_device_state(udev, USB_STATE_DEFAULT);
3075		}
3076	} else {
3077		if (udev)
3078			usb_set_device_state(udev, USB_STATE_NOTATTACHED);
3079	}
3080
3081	if (!hub_is_superspeed(hub->hdev))
3082		up_read(&ehci_cf_port_reset_rwsem);
3083
3084	return status;
3085}
3086
3087/*
3088 * hub_port_stop_enumerate - stop USB enumeration or ignore port events
3089 * @hub: target hub
3090 * @port1: port num of the port
3091 * @retries: port retries number of hub_port_init()
3092 *
3093 * Return:
3094 *    true: ignore port actions/events or give up connection attempts.
3095 *    false: keep original behavior.
3096 *
3097 * This function will be based on retries to check whether the port which is
3098 * marked with early_stop attribute would stop enumeration or ignore events.
3099 *
3100 * Note:
3101 * This function didn't change anything if early_stop is not set, and it will
3102 * prevent all connection attempts when early_stop is set and the attempts of
3103 * the port are more than 1.
3104 */
3105static bool hub_port_stop_enumerate(struct usb_hub *hub, int port1, int retries)
3106{
3107	struct usb_port *port_dev = hub->ports[port1 - 1];
3108
3109	if (port_dev->early_stop) {
3110		if (port_dev->ignore_event)
3111			return true;
3112
3113		/*
3114		 * We want unsuccessful attempts to fail quickly.
3115		 * Since some devices may need one failure during
3116		 * port initialization, we allow two tries but no
3117		 * more.
3118		 */
3119		if (retries < 2)
3120			return false;
3121
3122		port_dev->ignore_event = 1;
3123	} else
3124		port_dev->ignore_event = 0;
3125
3126	return port_dev->ignore_event;
3127}
3128
3129/* Check if a port is power on */
3130int usb_port_is_power_on(struct usb_hub *hub, unsigned int portstatus)
3131{
3132	int ret = 0;
3133
3134	if (hub_is_superspeed(hub->hdev)) {
3135		if (portstatus & USB_SS_PORT_STAT_POWER)
3136			ret = 1;
3137	} else {
3138		if (portstatus & USB_PORT_STAT_POWER)
3139			ret = 1;
3140	}
3141
3142	return ret;
3143}
3144
3145static void usb_lock_port(struct usb_port *port_dev)
3146		__acquires(&port_dev->status_lock)
3147{
3148	mutex_lock(&port_dev->status_lock);
3149	__acquire(&port_dev->status_lock);
3150}
3151
3152static void usb_unlock_port(struct usb_port *port_dev)
3153		__releases(&port_dev->status_lock)
3154{
3155	mutex_unlock(&port_dev->status_lock);
3156	__release(&port_dev->status_lock);
3157}
3158
3159#ifdef	CONFIG_PM
3160
3161/* Check if a port is suspended(USB2.0 port) or in U3 state(USB3.0 port) */
3162static int port_is_suspended(struct usb_hub *hub, unsigned portstatus)
3163{
3164	int ret = 0;
3165
3166	if (hub_is_superspeed(hub->hdev)) {
3167		if ((portstatus & USB_PORT_STAT_LINK_STATE)
3168				== USB_SS_PORT_LS_U3)
3169			ret = 1;
3170	} else {
3171		if (portstatus & USB_PORT_STAT_SUSPEND)
3172			ret = 1;
3173	}
3174
3175	return ret;
3176}
3177
3178/* Determine whether the device on a port is ready for a normal resume,
3179 * is ready for a reset-resume, or should be disconnected.
3180 */
3181static int check_port_resume_type(struct usb_device *udev,
3182		struct usb_hub *hub, int port1,
3183		int status, u16 portchange, u16 portstatus)
3184{
3185	struct usb_port *port_dev = hub->ports[port1 - 1];
3186	int retries = 3;
3187
3188 retry:
3189	/* Is a warm reset needed to recover the connection? */
3190	if (status == 0 && udev->reset_resume
3191		&& hub_port_warm_reset_required(hub, port1, portstatus)) {
3192		/* pass */;
3193	}
3194	/* Is the device still present? */
3195	else if (status || port_is_suspended(hub, portstatus) ||
3196			!usb_port_is_power_on(hub, portstatus)) {
3197		if (status >= 0)
3198			status = -ENODEV;
3199	} else if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
3200		if (retries--) {
3201			usleep_range(200, 300);
3202			status = usb_hub_port_status(hub, port1, &portstatus,
3203							     &portchange);
3204			goto retry;
3205		}
3206		status = -ENODEV;
3207	}
3208
3209	/* Can't do a normal resume if the port isn't enabled,
3210	 * so try a reset-resume instead.
3211	 */
3212	else if (!(portstatus & USB_PORT_STAT_ENABLE) && !udev->reset_resume) {
3213		if (udev->persist_enabled)
3214			udev->reset_resume = 1;
3215		else
3216			status = -ENODEV;
3217	}
3218
3219	if (status) {
3220		dev_dbg(&port_dev->dev, "status %04x.%04x after resume, %d\n",
3221				portchange, portstatus, status);
3222	} else if (udev->reset_resume) {
3223
3224		/* Late port handoff can set status-change bits */
3225		if (portchange & USB_PORT_STAT_C_CONNECTION)
3226			usb_clear_port_feature(hub->hdev, port1,
3227					USB_PORT_FEAT_C_CONNECTION);
3228		if (portchange & USB_PORT_STAT_C_ENABLE)
3229			usb_clear_port_feature(hub->hdev, port1,
3230					USB_PORT_FEAT_C_ENABLE);
3231
3232		/*
3233		 * Whatever made this reset-resume necessary may have
3234		 * turned on the port1 bit in hub->change_bits.  But after
3235		 * a successful reset-resume we want the bit to be clear;
3236		 * if it was on it would indicate that something happened
3237		 * following the reset-resume.
3238		 */
3239		clear_bit(port1, hub->change_bits);
3240	}
3241
3242	return status;
3243}
3244
3245int usb_disable_ltm(struct usb_device *udev)
3246{
3247	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3248
3249	/* Check if the roothub and device supports LTM. */
3250	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3251			!usb_device_supports_ltm(udev))
3252		return 0;
3253
3254	/* Clear Feature LTM Enable can only be sent if the device is
3255	 * configured.
3256	 */
3257	if (!udev->actconfig)
3258		return 0;
3259
3260	return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3261			USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3262			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3263			USB_CTRL_SET_TIMEOUT);
3264}
3265EXPORT_SYMBOL_GPL(usb_disable_ltm);
3266
3267void usb_enable_ltm(struct usb_device *udev)
3268{
3269	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
3270
3271	/* Check if the roothub and device supports LTM. */
3272	if (!usb_device_supports_ltm(hcd->self.root_hub) ||
3273			!usb_device_supports_ltm(udev))
3274		return;
3275
3276	/* Set Feature LTM Enable can only be sent if the device is
3277	 * configured.
3278	 */
3279	if (!udev->actconfig)
3280		return;
3281
3282	usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3283			USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3284			USB_DEVICE_LTM_ENABLE, 0, NULL, 0,
3285			USB_CTRL_SET_TIMEOUT);
3286}
3287EXPORT_SYMBOL_GPL(usb_enable_ltm);
3288
3289/*
3290 * usb_enable_remote_wakeup - enable remote wakeup for a device
3291 * @udev: target device
3292 *
3293 * For USB-2 devices: Set the device's remote wakeup feature.
3294 *
3295 * For USB-3 devices: Assume there's only one function on the device and
3296 * enable remote wake for the first interface.  FIXME if the interface
3297 * association descriptor shows there's more than one function.
3298 */
3299static int usb_enable_remote_wakeup(struct usb_device *udev)
3300{
3301	if (udev->speed < USB_SPEED_SUPER)
3302		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3303				USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
3304				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3305				USB_CTRL_SET_TIMEOUT);
3306	else
3307		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3308				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3309				USB_INTRF_FUNC_SUSPEND,
3310				USB_INTRF_FUNC_SUSPEND_RW |
3311					USB_INTRF_FUNC_SUSPEND_LP,
3312				NULL, 0, USB_CTRL_SET_TIMEOUT);
3313}
3314
3315/*
3316 * usb_disable_remote_wakeup - disable remote wakeup for a device
3317 * @udev: target device
3318 *
3319 * For USB-2 devices: Clear the device's remote wakeup feature.
3320 *
3321 * For USB-3 devices: Assume there's only one function on the device and
3322 * disable remote wake for the first interface.  FIXME if the interface
3323 * association descriptor shows there's more than one function.
3324 */
3325static int usb_disable_remote_wakeup(struct usb_device *udev)
3326{
3327	if (udev->speed < USB_SPEED_SUPER)
3328		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3329				USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
3330				USB_DEVICE_REMOTE_WAKEUP, 0, NULL, 0,
3331				USB_CTRL_SET_TIMEOUT);
3332	else
3333		return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3334				USB_REQ_SET_FEATURE, USB_RECIP_INTERFACE,
3335				USB_INTRF_FUNC_SUSPEND,	0, NULL, 0,
3336				USB_CTRL_SET_TIMEOUT);
3337}
3338
3339/* Count of wakeup-enabled devices at or below udev */
3340unsigned usb_wakeup_enabled_descendants(struct usb_device *udev)
3341{
3342	struct usb_hub *hub = usb_hub_to_struct_hub(udev);
3343
3344	return udev->do_remote_wakeup +
3345			(hub ? hub->wakeup_enabled_descendants : 0);
3346}
3347EXPORT_SYMBOL_GPL(usb_wakeup_enabled_descendants);
3348
3349/*
3350 * usb_port_suspend - suspend a usb device's upstream port
3351 * @udev: device that's no longer in active use, not a root hub
3352 * Context: must be able to sleep; device not locked; pm locks held
3353 *
3354 * Suspends a USB device that isn't in active use, conserving power.
3355 * Devices may wake out of a suspend, if anything important happens,
3356 * using the remote wakeup mechanism.  They may also be taken out of
3357 * suspend by the host, using usb_port_resume().  It's also routine
3358 * to disconnect devices while they are suspended.
3359 *
3360 * This only affects the USB hardware for a device; its interfaces
3361 * (and, for hubs, child devices) must already have been suspended.
3362 *
3363 * Selective port suspend reduces power; most suspended devices draw
3364 * less than 500 uA.  It's also used in OTG, along with remote wakeup.
3365 * All devices below the suspended port are also suspended.
3366 *
3367 * Devices leave suspend state when the host wakes them up.  Some devices
3368 * also support "remote wakeup", where the device can activate the USB
3369 * tree above them to deliver data, such as a keypress or packet.  In
3370 * some cases, this wakes the USB host.
3371 *
3372 * Suspending OTG devices may trigger HNP, if that's been enabled
3373 * between a pair of dual-role devices.  That will change roles, such
3374 * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
3375 *
3376 * Devices on USB hub ports have only one "suspend" state, corresponding
3377 * to ACPI D2, "may cause the device to lose some context".
3378 * State transitions include:
3379 *
3380 *   - suspend, resume ... when the VBUS power link stays live
3381 *   - suspend, disconnect ... VBUS lost
3382 *
3383 * Once VBUS drop breaks the circuit, the port it's using has to go through
3384 * normal re-enumeration procedures, starting with enabling VBUS power.
3385 * Other than re-initializing the hub (plug/unplug, except for root hubs),
3386 * Linux (2.6) currently has NO mechanisms to initiate that:  no hub_wq
3387 * timer, no SRP, no requests through sysfs.
3388 *
3389 * If Runtime PM isn't enabled or used, non-SuperSpeed devices may not get
3390 * suspended until their bus goes into global suspend (i.e., the root
3391 * hub is suspended).  Nevertheless, we change @udev->state to
3392 * USB_STATE_SUSPENDED as this is the device's "logical" state.  The actual
3393 * upstream port setting is stored in @udev->port_is_suspended.
3394 *
3395 * Returns 0 on success, else negative errno.
3396 */
3397int usb_port_suspend(struct usb_device *udev, pm_message_t msg)
3398{
3399	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3400	struct usb_port *port_dev = hub->ports[udev->portnum - 1];
3401	int		port1 = udev->portnum;
3402	int		status;
3403	bool		really_suspend = true;
3404
3405	usb_lock_port(port_dev);
3406
3407	/* enable remote wakeup when appropriate; this lets the device
3408	 * wake up the upstream hub (including maybe the root hub).
3409	 *
3410	 * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
3411	 * we don't explicitly enable it here.
3412	 */
3413	if (udev->do_remote_wakeup) {
3414		status = usb_enable_remote_wakeup(udev);
3415		if (status) {
3416			dev_dbg(&udev->dev, "won't remote wakeup, status %d\n",
3417					status);
3418			/* bail if autosuspend is requested */
3419			if (PMSG_IS_AUTO(msg))
3420				goto err_wakeup;
3421		}
3422	}
3423
3424	/* disable USB2 hardware LPM */
3425	usb_disable_usb2_hardware_lpm(udev);
 
3426
3427	if (usb_disable_ltm(udev)) {
3428		dev_err(&udev->dev, "Failed to disable LTM before suspend\n");
3429		status = -ENOMEM;
3430		if (PMSG_IS_AUTO(msg))
3431			goto err_ltm;
3432	}
 
 
 
 
 
 
3433
3434	/* see 7.1.7.6 */
3435	if (hub_is_superspeed(hub->hdev))
3436		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U3);
3437
3438	/*
3439	 * For system suspend, we do not need to enable the suspend feature
3440	 * on individual USB-2 ports.  The devices will automatically go
3441	 * into suspend a few ms after the root hub stops sending packets.
3442	 * The USB 2.0 spec calls this "global suspend".
3443	 *
3444	 * However, many USB hubs have a bug: They don't relay wakeup requests
3445	 * from a downstream port if the port's suspend feature isn't on.
3446	 * Therefore we will turn on the suspend feature if udev or any of its
3447	 * descendants is enabled for remote wakeup.
3448	 */
3449	else if (PMSG_IS_AUTO(msg) || usb_wakeup_enabled_descendants(udev) > 0)
3450		status = set_port_feature(hub->hdev, port1,
3451				USB_PORT_FEAT_SUSPEND);
3452	else {
3453		really_suspend = false;
3454		status = 0;
3455	}
3456	if (status) {
3457		/* Check if the port has been suspended for the timeout case
3458		 * to prevent the suspended port from incorrect handling.
3459		 */
3460		if (status == -ETIMEDOUT) {
3461			int ret;
3462			u16 portstatus, portchange;
3463
3464			portstatus = portchange = 0;
3465			ret = usb_hub_port_status(hub, port1, &portstatus,
3466					&portchange);
3467
3468			dev_dbg(&port_dev->dev,
3469				"suspend timeout, status %04x\n", portstatus);
3470
3471			if (ret == 0 && port_is_suspended(hub, portstatus)) {
3472				status = 0;
3473				goto suspend_done;
3474			}
3475		}
3476
3477		dev_dbg(&port_dev->dev, "can't suspend, status %d\n", status);
3478
3479		/* Try to enable USB3 LTM again */
 
 
3480		usb_enable_ltm(udev);
3481 err_ltm:
3482		/* Try to enable USB2 hardware LPM again */
3483		usb_enable_usb2_hardware_lpm(udev);
 
3484
3485		if (udev->do_remote_wakeup)
3486			(void) usb_disable_remote_wakeup(udev);
3487 err_wakeup:
3488
3489		/* System sleep transitions should never fail */
3490		if (!PMSG_IS_AUTO(msg))
3491			status = 0;
3492	} else {
3493 suspend_done:
3494		dev_dbg(&udev->dev, "usb %ssuspend, wakeup %d\n",
3495				(PMSG_IS_AUTO(msg) ? "auto-" : ""),
3496				udev->do_remote_wakeup);
3497		if (really_suspend) {
3498			udev->port_is_suspended = 1;
3499
3500			/* device has up to 10 msec to fully suspend */
3501			msleep(10);
3502		}
3503		usb_set_device_state(udev, USB_STATE_SUSPENDED);
3504	}
3505
3506	if (status == 0 && !udev->do_remote_wakeup && udev->persist_enabled
3507			&& test_and_clear_bit(port1, hub->child_usage_bits))
3508		pm_runtime_put_sync(&port_dev->dev);
3509
3510	usb_mark_last_busy(hub->hdev);
3511
3512	usb_unlock_port(port_dev);
3513	return status;
3514}
3515
3516/*
3517 * If the USB "suspend" state is in use (rather than "global suspend"),
3518 * many devices will be individually taken out of suspend state using
3519 * special "resume" signaling.  This routine kicks in shortly after
3520 * hardware resume signaling is finished, either because of selective
3521 * resume (by host) or remote wakeup (by device) ... now see what changed
3522 * in the tree that's rooted at this device.
3523 *
3524 * If @udev->reset_resume is set then the device is reset before the
3525 * status check is done.
3526 */
3527static int finish_port_resume(struct usb_device *udev)
3528{
3529	int	status = 0;
3530	u16	devstatus = 0;
3531
3532	/* caller owns the udev device lock */
3533	dev_dbg(&udev->dev, "%s\n",
3534		udev->reset_resume ? "finish reset-resume" : "finish resume");
3535
3536	/* usb ch9 identifies four variants of SUSPENDED, based on what
3537	 * state the device resumes to.  Linux currently won't see the
3538	 * first two on the host side; they'd be inside hub_port_init()
3539	 * during many timeouts, but hub_wq can't suspend until later.
3540	 */
3541	usb_set_device_state(udev, udev->actconfig
3542			? USB_STATE_CONFIGURED
3543			: USB_STATE_ADDRESS);
3544
3545	/* 10.5.4.5 says not to reset a suspended port if the attached
3546	 * device is enabled for remote wakeup.  Hence the reset
3547	 * operation is carried out here, after the port has been
3548	 * resumed.
3549	 */
3550	if (udev->reset_resume) {
3551		/*
3552		 * If the device morphs or switches modes when it is reset,
3553		 * we don't want to perform a reset-resume.  We'll fail the
3554		 * resume, which will cause a logical disconnect, and then
3555		 * the device will be rediscovered.
3556		 */
3557 retry_reset_resume:
3558		if (udev->quirks & USB_QUIRK_RESET)
3559			status = -ENODEV;
3560		else
3561			status = usb_reset_and_verify_device(udev);
3562	}
3563
3564	/* 10.5.4.5 says be sure devices in the tree are still there.
3565	 * For now let's assume the device didn't go crazy on resume,
3566	 * and device drivers will know about any resume quirks.
3567	 */
3568	if (status == 0) {
3569		devstatus = 0;
3570		status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
3571
3572		/* If a normal resume failed, try doing a reset-resume */
3573		if (status && !udev->reset_resume && udev->persist_enabled) {
3574			dev_dbg(&udev->dev, "retry with reset-resume\n");
3575			udev->reset_resume = 1;
3576			goto retry_reset_resume;
3577		}
3578	}
3579
3580	if (status) {
3581		dev_dbg(&udev->dev, "gone after usb resume? status %d\n",
3582				status);
3583	/*
3584	 * There are a few quirky devices which violate the standard
3585	 * by claiming to have remote wakeup enabled after a reset,
3586	 * which crash if the feature is cleared, hence check for
3587	 * udev->reset_resume
3588	 */
3589	} else if (udev->actconfig && !udev->reset_resume) {
3590		if (udev->speed < USB_SPEED_SUPER) {
3591			if (devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
3592				status = usb_disable_remote_wakeup(udev);
3593		} else {
3594			status = usb_get_std_status(udev, USB_RECIP_INTERFACE, 0,
3595					&devstatus);
3596			if (!status && devstatus & (USB_INTRF_STAT_FUNC_RW_CAP
3597					| USB_INTRF_STAT_FUNC_RW))
3598				status = usb_disable_remote_wakeup(udev);
3599		}
3600
3601		if (status)
3602			dev_dbg(&udev->dev,
3603				"disable remote wakeup, status %d\n",
3604				status);
3605		status = 0;
3606	}
3607	return status;
3608}
3609
3610/*
3611 * There are some SS USB devices which take longer time for link training.
3612 * XHCI specs 4.19.4 says that when Link training is successful, port
3613 * sets CCS bit to 1. So if SW reads port status before successful link
3614 * training, then it will not find device to be present.
3615 * USB Analyzer log with such buggy devices show that in some cases
3616 * device switch on the RX termination after long delay of host enabling
3617 * the VBUS. In few other cases it has been seen that device fails to
3618 * negotiate link training in first attempt. It has been
3619 * reported till now that few devices take as long as 2000 ms to train
3620 * the link after host enabling its VBUS and termination. Following
3621 * routine implements a 2000 ms timeout for link training. If in a case
3622 * link trains before timeout, loop will exit earlier.
3623 *
3624 * There are also some 2.0 hard drive based devices and 3.0 thumb
3625 * drives that, when plugged into a 2.0 only port, take a long
3626 * time to set CCS after VBUS enable.
3627 *
3628 * FIXME: If a device was connected before suspend, but was removed
3629 * while system was asleep, then the loop in the following routine will
3630 * only exit at timeout.
3631 *
3632 * This routine should only be called when persist is enabled.
3633 */
3634static int wait_for_connected(struct usb_device *udev,
3635		struct usb_hub *hub, int port1,
3636		u16 *portchange, u16 *portstatus)
3637{
3638	int status = 0, delay_ms = 0;
3639
3640	while (delay_ms < 2000) {
3641		if (status || *portstatus & USB_PORT_STAT_CONNECTION)
3642			break;
3643		if (!usb_port_is_power_on(hub, *portstatus)) {
3644			status = -ENODEV;
3645			break;
3646		}
3647		msleep(20);
3648		delay_ms += 20;
3649		status = usb_hub_port_status(hub, port1, portstatus, portchange);
3650	}
3651	dev_dbg(&udev->dev, "Waited %dms for CONNECT\n", delay_ms);
3652	return status;
3653}
3654
3655/*
3656 * usb_port_resume - re-activate a suspended usb device's upstream port
3657 * @udev: device to re-activate, not a root hub
3658 * Context: must be able to sleep; device not locked; pm locks held
3659 *
3660 * This will re-activate the suspended device, increasing power usage
3661 * while letting drivers communicate again with its endpoints.
3662 * USB resume explicitly guarantees that the power session between
3663 * the host and the device is the same as it was when the device
3664 * suspended.
3665 *
3666 * If @udev->reset_resume is set then this routine won't check that the
3667 * port is still enabled.  Furthermore, finish_port_resume() above will
3668 * reset @udev.  The end result is that a broken power session can be
3669 * recovered and @udev will appear to persist across a loss of VBUS power.
3670 *
3671 * For example, if a host controller doesn't maintain VBUS suspend current
3672 * during a system sleep or is reset when the system wakes up, all the USB
3673 * power sessions below it will be broken.  This is especially troublesome
3674 * for mass-storage devices containing mounted filesystems, since the
3675 * device will appear to have disconnected and all the memory mappings
3676 * to it will be lost.  Using the USB_PERSIST facility, the device can be
3677 * made to appear as if it had not disconnected.
3678 *
3679 * This facility can be dangerous.  Although usb_reset_and_verify_device() makes
3680 * every effort to insure that the same device is present after the
3681 * reset as before, it cannot provide a 100% guarantee.  Furthermore it's
3682 * quite possible for a device to remain unaltered but its media to be
3683 * changed.  If the user replaces a flash memory card while the system is
3684 * asleep, he will have only himself to blame when the filesystem on the
3685 * new card is corrupted and the system crashes.
3686 *
3687 * Returns 0 on success, else negative errno.
3688 */
3689int usb_port_resume(struct usb_device *udev, pm_message_t msg)
3690{
3691	struct usb_hub	*hub = usb_hub_to_struct_hub(udev->parent);
3692	struct usb_port *port_dev = hub->ports[udev->portnum  - 1];
3693	int		port1 = udev->portnum;
3694	int		status;
3695	u16		portchange, portstatus;
3696
3697	if (!test_and_set_bit(port1, hub->child_usage_bits)) {
3698		status = pm_runtime_resume_and_get(&port_dev->dev);
3699		if (status < 0) {
3700			dev_dbg(&udev->dev, "can't resume usb port, status %d\n",
3701					status);
3702			return status;
3703		}
3704	}
3705
3706	usb_lock_port(port_dev);
3707
3708	/* Skip the initial Clear-Suspend step for a remote wakeup */
3709	status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3710	if (status == 0 && !port_is_suspended(hub, portstatus)) {
3711		if (portchange & USB_PORT_STAT_C_SUSPEND)
3712			pm_wakeup_event(&udev->dev, 0);
3713		goto SuspendCleared;
3714	}
3715
3716	/* see 7.1.7.7; affects power usage, but not budgeting */
3717	if (hub_is_superspeed(hub->hdev))
3718		status = hub_set_port_link_state(hub, port1, USB_SS_PORT_LS_U0);
3719	else
3720		status = usb_clear_port_feature(hub->hdev,
3721				port1, USB_PORT_FEAT_SUSPEND);
3722	if (status) {
3723		dev_dbg(&port_dev->dev, "can't resume, status %d\n", status);
3724	} else {
3725		/* drive resume for USB_RESUME_TIMEOUT msec */
3726		dev_dbg(&udev->dev, "usb %sresume\n",
3727				(PMSG_IS_AUTO(msg) ? "auto-" : ""));
3728		msleep(USB_RESUME_TIMEOUT);
3729
3730		/* Virtual root hubs can trigger on GET_PORT_STATUS to
3731		 * stop resume signaling.  Then finish the resume
3732		 * sequence.
3733		 */
3734		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
 
 
 
3735	}
3736
3737 SuspendCleared:
3738	if (status == 0) {
3739		udev->port_is_suspended = 0;
3740		if (hub_is_superspeed(hub->hdev)) {
3741			if (portchange & USB_PORT_STAT_C_LINK_STATE)
3742				usb_clear_port_feature(hub->hdev, port1,
3743					USB_PORT_FEAT_C_PORT_LINK_STATE);
3744		} else {
3745			if (portchange & USB_PORT_STAT_C_SUSPEND)
3746				usb_clear_port_feature(hub->hdev, port1,
3747						USB_PORT_FEAT_C_SUSPEND);
3748		}
3749
3750		/* TRSMRCY = 10 msec */
3751		msleep(10);
3752	}
3753
3754	if (udev->persist_enabled)
3755		status = wait_for_connected(udev, hub, port1, &portchange,
3756				&portstatus);
3757
3758	status = check_port_resume_type(udev,
3759			hub, port1, status, portchange, portstatus);
3760	if (status == 0)
3761		status = finish_port_resume(udev);
3762	if (status < 0) {
3763		dev_dbg(&udev->dev, "can't resume, status %d\n", status);
3764		hub_port_logical_disconnect(hub, port1);
3765	} else  {
3766		/* Try to enable USB2 hardware LPM */
3767		usb_enable_usb2_hardware_lpm(udev);
 
3768
3769		/* Try to enable USB3 LTM */
3770		usb_enable_ltm(udev);
 
3771	}
3772
3773	usb_unlock_port(port_dev);
3774
3775	return status;
3776}
3777
3778int usb_remote_wakeup(struct usb_device *udev)
3779{
3780	int	status = 0;
3781
3782	usb_lock_device(udev);
3783	if (udev->state == USB_STATE_SUSPENDED) {
3784		dev_dbg(&udev->dev, "usb %sresume\n", "wakeup-");
3785		status = usb_autoresume_device(udev);
3786		if (status == 0) {
3787			/* Let the drivers do their thing, then... */
3788			usb_autosuspend_device(udev);
3789		}
3790	}
3791	usb_unlock_device(udev);
3792	return status;
3793}
3794
3795/* Returns 1 if there was a remote wakeup and a connect status change. */
3796static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
3797		u16 portstatus, u16 portchange)
3798		__must_hold(&port_dev->status_lock)
3799{
3800	struct usb_port *port_dev = hub->ports[port - 1];
3801	struct usb_device *hdev;
3802	struct usb_device *udev;
3803	int connect_change = 0;
3804	u16 link_state;
3805	int ret;
3806
3807	hdev = hub->hdev;
3808	udev = port_dev->child;
3809	if (!hub_is_superspeed(hdev)) {
3810		if (!(portchange & USB_PORT_STAT_C_SUSPEND))
3811			return 0;
3812		usb_clear_port_feature(hdev, port, USB_PORT_FEAT_C_SUSPEND);
3813	} else {
3814		link_state = portstatus & USB_PORT_STAT_LINK_STATE;
3815		if (!udev || udev->state != USB_STATE_SUSPENDED ||
3816				(link_state != USB_SS_PORT_LS_U0 &&
3817				 link_state != USB_SS_PORT_LS_U1 &&
3818				 link_state != USB_SS_PORT_LS_U2))
3819			return 0;
3820	}
3821
3822	if (udev) {
3823		/* TRSMRCY = 10 msec */
3824		msleep(10);
3825
3826		usb_unlock_port(port_dev);
3827		ret = usb_remote_wakeup(udev);
3828		usb_lock_port(port_dev);
3829		if (ret < 0)
3830			connect_change = 1;
3831	} else {
3832		ret = -ENODEV;
3833		hub_port_disable(hub, port, 1);
3834	}
3835	dev_dbg(&port_dev->dev, "resume, status %d\n", ret);
3836	return connect_change;
3837}
3838
3839static int check_ports_changed(struct usb_hub *hub)
3840{
3841	int port1;
3842
3843	for (port1 = 1; port1 <= hub->hdev->maxchild; ++port1) {
3844		u16 portstatus, portchange;
3845		int status;
3846
3847		status = usb_hub_port_status(hub, port1, &portstatus, &portchange);
3848		if (!status && portchange)
3849			return 1;
3850	}
3851	return 0;
3852}
3853
3854static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
3855{
3856	struct usb_hub		*hub = usb_get_intfdata(intf);
3857	struct usb_device	*hdev = hub->hdev;
3858	unsigned		port1;
 
3859
3860	/*
3861	 * Warn if children aren't already suspended.
3862	 * Also, add up the number of wakeup-enabled descendants.
3863	 */
3864	hub->wakeup_enabled_descendants = 0;
3865	for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3866		struct usb_port *port_dev = hub->ports[port1 - 1];
3867		struct usb_device *udev = port_dev->child;
3868
3869		if (udev && udev->can_submit) {
3870			dev_warn(&port_dev->dev, "device %s not suspended yet\n",
3871					dev_name(&udev->dev));
3872			if (PMSG_IS_AUTO(msg))
3873				return -EBUSY;
3874		}
3875		if (udev)
3876			hub->wakeup_enabled_descendants +=
3877					usb_wakeup_enabled_descendants(udev);
3878	}
3879
3880	if (hdev->do_remote_wakeup && hub->quirk_check_port_auto_suspend) {
3881		/* check if there are changes pending on hub ports */
3882		if (check_ports_changed(hub)) {
3883			if (PMSG_IS_AUTO(msg))
3884				return -EBUSY;
3885			pm_wakeup_event(&hdev->dev, 2000);
3886		}
3887	}
3888
3889	if (hub_is_superspeed(hdev) && hdev->do_remote_wakeup) {
3890		/* Enable hub to send remote wakeup for all ports. */
3891		for (port1 = 1; port1 <= hdev->maxchild; port1++) {
3892			set_port_feature(hdev,
3893					 port1 |
3894					 USB_PORT_FEAT_REMOTE_WAKE_CONNECT |
3895					 USB_PORT_FEAT_REMOTE_WAKE_DISCONNECT |
3896					 USB_PORT_FEAT_REMOTE_WAKE_OVER_CURRENT,
3897					 USB_PORT_FEAT_REMOTE_WAKE_MASK);
3898		}
3899	}
3900
3901	dev_dbg(&intf->dev, "%s\n", __func__);
3902
3903	/* stop hub_wq and related activity */
3904	hub_quiesce(hub, HUB_SUSPEND);
3905	return 0;
3906}
3907
3908/* Report wakeup requests from the ports of a resuming root hub */
3909static void report_wakeup_requests(struct usb_hub *hub)
3910{
3911	struct usb_device	*hdev = hub->hdev;
3912	struct usb_device	*udev;
3913	struct usb_hcd		*hcd;
3914	unsigned long		resuming_ports;
3915	int			i;
3916
3917	if (hdev->parent)
3918		return;		/* Not a root hub */
3919
3920	hcd = bus_to_hcd(hdev->bus);
3921	if (hcd->driver->get_resuming_ports) {
3922
3923		/*
3924		 * The get_resuming_ports() method returns a bitmap (origin 0)
3925		 * of ports which have started wakeup signaling but have not
3926		 * yet finished resuming.  During system resume we will
3927		 * resume all the enabled ports, regardless of any wakeup
3928		 * signals, which means the wakeup requests would be lost.
3929		 * To prevent this, report them to the PM core here.
3930		 */
3931		resuming_ports = hcd->driver->get_resuming_ports(hcd);
3932		for (i = 0; i < hdev->maxchild; ++i) {
3933			if (test_bit(i, &resuming_ports)) {
3934				udev = hub->ports[i]->child;
3935				if (udev)
3936					pm_wakeup_event(&udev->dev, 0);
3937			}
3938		}
3939	}
3940}
3941
3942static int hub_resume(struct usb_interface *intf)
3943{
3944	struct usb_hub *hub = usb_get_intfdata(intf);
3945
3946	dev_dbg(&intf->dev, "%s\n", __func__);
3947	hub_activate(hub, HUB_RESUME);
3948
3949	/*
3950	 * This should be called only for system resume, not runtime resume.
3951	 * We can't tell the difference here, so some wakeup requests will be
3952	 * reported at the wrong time or more than once.  This shouldn't
3953	 * matter much, so long as they do get reported.
3954	 */
3955	report_wakeup_requests(hub);
3956	return 0;
3957}
3958
3959static int hub_reset_resume(struct usb_interface *intf)
3960{
3961	struct usb_hub *hub = usb_get_intfdata(intf);
3962
3963	dev_dbg(&intf->dev, "%s\n", __func__);
3964	hub_activate(hub, HUB_RESET_RESUME);
3965	return 0;
3966}
3967
3968/**
3969 * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
3970 * @rhdev: struct usb_device for the root hub
3971 *
3972 * The USB host controller driver calls this function when its root hub
3973 * is resumed and Vbus power has been interrupted or the controller
3974 * has been reset.  The routine marks @rhdev as having lost power.
3975 * When the hub driver is resumed it will take notice and carry out
3976 * power-session recovery for all the "USB-PERSIST"-enabled child devices;
3977 * the others will be disconnected.
3978 */
3979void usb_root_hub_lost_power(struct usb_device *rhdev)
3980{
3981	dev_notice(&rhdev->dev, "root hub lost power or was reset\n");
3982	rhdev->reset_resume = 1;
3983}
3984EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
3985
3986static const char * const usb3_lpm_names[]  = {
3987	"U0",
3988	"U1",
3989	"U2",
3990	"U3",
3991};
3992
3993/*
3994 * Send a Set SEL control transfer to the device, prior to enabling
3995 * device-initiated U1 or U2.  This lets the device know the exit latencies from
3996 * the time the device initiates a U1 or U2 exit, to the time it will receive a
3997 * packet from the host.
3998 *
3999 * This function will fail if the SEL or PEL values for udev are greater than
4000 * the maximum allowed values for the link state to be enabled.
4001 */
4002static int usb_req_set_sel(struct usb_device *udev)
4003{
4004	struct usb_set_sel_req *sel_values;
4005	unsigned long long u1_sel;
4006	unsigned long long u1_pel;
4007	unsigned long long u2_sel;
4008	unsigned long long u2_pel;
4009	int ret;
4010
4011	if (!udev->parent || udev->speed < USB_SPEED_SUPER || !udev->lpm_capable)
4012		return 0;
4013
4014	/* Convert SEL and PEL stored in ns to us */
4015	u1_sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
4016	u1_pel = DIV_ROUND_UP(udev->u1_params.pel, 1000);
4017	u2_sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
4018	u2_pel = DIV_ROUND_UP(udev->u2_params.pel, 1000);
4019
4020	/*
4021	 * Make sure that the calculated SEL and PEL values for the link
4022	 * state we're enabling aren't bigger than the max SEL/PEL
4023	 * value that will fit in the SET SEL control transfer.
4024	 * Otherwise the device would get an incorrect idea of the exit
4025	 * latency for the link state, and could start a device-initiated
4026	 * U1/U2 when the exit latencies are too high.
4027	 */
4028	if (u1_sel > USB3_LPM_MAX_U1_SEL_PEL ||
4029	    u1_pel > USB3_LPM_MAX_U1_SEL_PEL ||
4030	    u2_sel > USB3_LPM_MAX_U2_SEL_PEL ||
4031	    u2_pel > USB3_LPM_MAX_U2_SEL_PEL) {
4032		dev_dbg(&udev->dev, "Device-initiated U1/U2 disabled due to long SEL or PEL\n");
 
 
 
4033		return -EINVAL;
4034	}
4035
4036	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4037	 * usb_enable_lpm() can be called as part of a failed device reset,
4038	 * which may be initiated by an error path of a mass storage driver.
4039	 * Therefore, use GFP_NOIO.
4040	 */
4041	sel_values = kmalloc(sizeof *(sel_values), GFP_NOIO);
4042	if (!sel_values)
4043		return -ENOMEM;
4044
4045	sel_values->u1_sel = u1_sel;
4046	sel_values->u1_pel = u1_pel;
4047	sel_values->u2_sel = cpu_to_le16(u2_sel);
4048	sel_values->u2_pel = cpu_to_le16(u2_pel);
4049
4050	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4051			USB_REQ_SET_SEL,
4052			USB_RECIP_DEVICE,
4053			0, 0,
4054			sel_values, sizeof *(sel_values),
4055			USB_CTRL_SET_TIMEOUT);
4056	kfree(sel_values);
4057
4058	if (ret > 0)
4059		udev->lpm_devinit_allow = 1;
4060
4061	return ret;
4062}
4063
4064/*
4065 * Enable or disable device-initiated U1 or U2 transitions.
4066 */
4067static int usb_set_device_initiated_lpm(struct usb_device *udev,
4068		enum usb3_link_state state, bool enable)
4069{
4070	int ret;
4071	int feature;
4072
4073	switch (state) {
4074	case USB3_LPM_U1:
4075		feature = USB_DEVICE_U1_ENABLE;
4076		break;
4077	case USB3_LPM_U2:
4078		feature = USB_DEVICE_U2_ENABLE;
4079		break;
4080	default:
4081		dev_warn(&udev->dev, "%s: Can't %s non-U1 or U2 state.\n",
4082				__func__, enable ? "enable" : "disable");
4083		return -EINVAL;
4084	}
4085
4086	if (udev->state != USB_STATE_CONFIGURED) {
4087		dev_dbg(&udev->dev, "%s: Can't %s %s state "
4088				"for unconfigured device.\n",
4089				__func__, enable ? "enable" : "disable",
4090				usb3_lpm_names[state]);
4091		return 0;
4092	}
4093
4094	if (enable) {
4095		/*
4096		 * Now send the control transfer to enable device-initiated LPM
4097		 * for either U1 or U2.
4098		 */
4099		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4100				USB_REQ_SET_FEATURE,
4101				USB_RECIP_DEVICE,
4102				feature,
4103				0, NULL, 0,
4104				USB_CTRL_SET_TIMEOUT);
4105	} else {
4106		ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
4107				USB_REQ_CLEAR_FEATURE,
4108				USB_RECIP_DEVICE,
4109				feature,
4110				0, NULL, 0,
4111				USB_CTRL_SET_TIMEOUT);
4112	}
4113	if (ret < 0) {
4114		dev_warn(&udev->dev, "%s of device-initiated %s failed.\n",
4115				enable ? "Enable" : "Disable",
4116				usb3_lpm_names[state]);
4117		return -EBUSY;
4118	}
4119	return 0;
4120}
4121
4122static int usb_set_lpm_timeout(struct usb_device *udev,
4123		enum usb3_link_state state, int timeout)
4124{
4125	int ret;
4126	int feature;
4127
4128	switch (state) {
4129	case USB3_LPM_U1:
4130		feature = USB_PORT_FEAT_U1_TIMEOUT;
4131		break;
4132	case USB3_LPM_U2:
4133		feature = USB_PORT_FEAT_U2_TIMEOUT;
4134		break;
4135	default:
4136		dev_warn(&udev->dev, "%s: Can't set timeout for non-U1 or U2 state.\n",
4137				__func__);
4138		return -EINVAL;
4139	}
4140
4141	if (state == USB3_LPM_U1 && timeout > USB3_LPM_U1_MAX_TIMEOUT &&
4142			timeout != USB3_LPM_DEVICE_INITIATED) {
4143		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x, "
4144				"which is a reserved value.\n",
4145				usb3_lpm_names[state], timeout);
4146		return -EINVAL;
4147	}
4148
4149	ret = set_port_feature(udev->parent,
4150			USB_PORT_LPM_TIMEOUT(timeout) | udev->portnum,
4151			feature);
4152	if (ret < 0) {
4153		dev_warn(&udev->dev, "Failed to set %s timeout to 0x%x,"
4154				"error code %i\n", usb3_lpm_names[state],
4155				timeout, ret);
4156		return -EBUSY;
4157	}
4158	if (state == USB3_LPM_U1)
4159		udev->u1_params.timeout = timeout;
4160	else
4161		udev->u2_params.timeout = timeout;
4162	return 0;
4163}
4164
4165/*
4166 * Don't allow device intiated U1/U2 if the system exit latency + one bus
4167 * interval is greater than the minimum service interval of any active
4168 * periodic endpoint. See USB 3.2 section 9.4.9
4169 */
4170static bool usb_device_may_initiate_lpm(struct usb_device *udev,
4171					enum usb3_link_state state)
4172{
4173	unsigned int sel;		/* us */
4174	int i, j;
4175
4176	if (!udev->lpm_devinit_allow)
4177		return false;
4178
4179	if (state == USB3_LPM_U1)
4180		sel = DIV_ROUND_UP(udev->u1_params.sel, 1000);
4181	else if (state == USB3_LPM_U2)
4182		sel = DIV_ROUND_UP(udev->u2_params.sel, 1000);
4183	else
4184		return false;
4185
4186	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
4187		struct usb_interface *intf;
4188		struct usb_endpoint_descriptor *desc;
4189		unsigned int interval;
4190
4191		intf = udev->actconfig->interface[i];
4192		if (!intf)
4193			continue;
4194
4195		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++) {
4196			desc = &intf->cur_altsetting->endpoint[j].desc;
4197
4198			if (usb_endpoint_xfer_int(desc) ||
4199			    usb_endpoint_xfer_isoc(desc)) {
4200				interval = (1 << (desc->bInterval - 1)) * 125;
4201				if (sel + 125 > interval)
4202					return false;
4203			}
4204		}
4205	}
4206	return true;
4207}
4208
4209/*
4210 * Enable the hub-initiated U1/U2 idle timeouts, and enable device-initiated
4211 * U1/U2 entry.
4212 *
4213 * We will attempt to enable U1 or U2, but there are no guarantees that the
4214 * control transfers to set the hub timeout or enable device-initiated U1/U2
4215 * will be successful.
4216 *
4217 * If the control transfer to enable device-initiated U1/U2 entry fails, then
4218 * hub-initiated U1/U2 will be disabled.
4219 *
4220 * If we cannot set the parent hub U1/U2 timeout, we attempt to let the xHCI
4221 * driver know about it.  If that call fails, it should be harmless, and just
4222 * take up more slightly more bus bandwidth for unnecessary U1/U2 exit latency.
4223 */
4224static void usb_enable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4225		enum usb3_link_state state)
4226{
4227	int timeout;
4228	__u8 u1_mel = udev->bos->ss_cap->bU1devExitLat;
4229	__le16 u2_mel = udev->bos->ss_cap->bU2DevExitLat;
4230
4231	/* If the device says it doesn't have *any* exit latency to come out of
4232	 * U1 or U2, it's probably lying.  Assume it doesn't implement that link
4233	 * state.
4234	 */
4235	if ((state == USB3_LPM_U1 && u1_mel == 0) ||
4236			(state == USB3_LPM_U2 && u2_mel == 0))
4237		return;
4238
 
 
 
 
 
 
 
 
 
 
 
4239	/* We allow the host controller to set the U1/U2 timeout internally
4240	 * first, so that it can change its schedule to account for the
4241	 * additional latency to send data to a device in a lower power
4242	 * link state.
4243	 */
4244	timeout = hcd->driver->enable_usb3_lpm_timeout(hcd, udev, state);
4245
4246	/* xHCI host controller doesn't want to enable this LPM state. */
4247	if (timeout == 0)
4248		return;
4249
4250	if (timeout < 0) {
4251		dev_warn(&udev->dev, "Could not enable %s link state, "
4252				"xHCI error %i.\n", usb3_lpm_names[state],
4253				timeout);
4254		return;
4255	}
4256
4257	if (usb_set_lpm_timeout(udev, state, timeout)) {
4258		/* If we can't set the parent hub U1/U2 timeout,
4259		 * device-initiated LPM won't be allowed either, so let the xHCI
4260		 * host know that this link state won't be enabled.
4261		 */
4262		hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4263		return;
4264	}
 
 
 
 
4265
4266	/* Only a configured device will accept the Set Feature
4267	 * U1/U2_ENABLE
4268	 */
4269	if (udev->actconfig &&
4270	    usb_device_may_initiate_lpm(udev, state)) {
4271		if (usb_set_device_initiated_lpm(udev, state, true)) {
4272			/*
4273			 * Request to enable device initiated U1/U2 failed,
4274			 * better to turn off lpm in this case.
4275			 */
4276			usb_set_lpm_timeout(udev, state, 0);
4277			hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state);
4278			return;
4279		}
4280	}
4281
4282	if (state == USB3_LPM_U1)
4283		udev->usb3_lpm_u1_enabled = 1;
4284	else if (state == USB3_LPM_U2)
4285		udev->usb3_lpm_u2_enabled = 1;
4286}
 
4287/*
4288 * Disable the hub-initiated U1/U2 idle timeouts, and disable device-initiated
4289 * U1/U2 entry.
4290 *
4291 * If this function returns -EBUSY, the parent hub will still allow U1/U2 entry.
4292 * If zero is returned, the parent will not allow the link to go into U1/U2.
4293 *
4294 * If zero is returned, device-initiated U1/U2 entry may still be enabled, but
4295 * it won't have an effect on the bus link state because the parent hub will
4296 * still disallow device-initiated U1/U2 entry.
4297 *
4298 * If zero is returned, the xHCI host controller may still think U1/U2 entry is
4299 * possible.  The result will be slightly more bus bandwidth will be taken up
4300 * (to account for U1/U2 exit latency), but it should be harmless.
4301 */
4302static int usb_disable_link_state(struct usb_hcd *hcd, struct usb_device *udev,
4303		enum usb3_link_state state)
4304{
4305	switch (state) {
4306	case USB3_LPM_U1:
4307	case USB3_LPM_U2:
4308		break;
4309	default:
4310		dev_warn(&udev->dev, "%s: Can't disable non-U1 or U2 state.\n",
4311				__func__);
4312		return -EINVAL;
4313	}
4314
4315	if (usb_set_lpm_timeout(udev, state, 0))
4316		return -EBUSY;
4317
4318	usb_set_device_initiated_lpm(udev, state, false);
4319
4320	if (hcd->driver->disable_usb3_lpm_timeout(hcd, udev, state))
4321		dev_warn(&udev->dev, "Could not disable xHCI %s timeout, "
4322				"bus schedule bandwidth may be impacted.\n",
4323				usb3_lpm_names[state]);
4324
4325	/* As soon as usb_set_lpm_timeout(0) return 0, hub initiated LPM
4326	 * is disabled. Hub will disallows link to enter U1/U2 as well,
4327	 * even device is initiating LPM. Hence LPM is disabled if hub LPM
4328	 * timeout set to 0, no matter device-initiated LPM is disabled or
4329	 * not.
4330	 */
4331	if (state == USB3_LPM_U1)
4332		udev->usb3_lpm_u1_enabled = 0;
4333	else if (state == USB3_LPM_U2)
4334		udev->usb3_lpm_u2_enabled = 0;
4335
4336	return 0;
4337}
4338
4339/*
4340 * Disable hub-initiated and device-initiated U1 and U2 entry.
4341 * Caller must own the bandwidth_mutex.
4342 *
4343 * This will call usb_enable_lpm() on failure, which will decrement
4344 * lpm_disable_count, and will re-enable LPM if lpm_disable_count reaches zero.
4345 */
4346int usb_disable_lpm(struct usb_device *udev)
4347{
4348	struct usb_hcd *hcd;
4349
4350	if (!udev || !udev->parent ||
4351			udev->speed < USB_SPEED_SUPER ||
4352			!udev->lpm_capable ||
4353			udev->state < USB_STATE_CONFIGURED)
4354		return 0;
4355
4356	hcd = bus_to_hcd(udev->bus);
4357	if (!hcd || !hcd->driver->disable_usb3_lpm_timeout)
4358		return 0;
4359
4360	udev->lpm_disable_count++;
4361	if ((udev->u1_params.timeout == 0 && udev->u2_params.timeout == 0))
4362		return 0;
4363
4364	/* If LPM is enabled, attempt to disable it. */
4365	if (usb_disable_link_state(hcd, udev, USB3_LPM_U1))
4366		goto enable_lpm;
4367	if (usb_disable_link_state(hcd, udev, USB3_LPM_U2))
4368		goto enable_lpm;
4369
4370	return 0;
4371
4372enable_lpm:
4373	usb_enable_lpm(udev);
4374	return -EBUSY;
4375}
4376EXPORT_SYMBOL_GPL(usb_disable_lpm);
4377
4378/* Grab the bandwidth_mutex before calling usb_disable_lpm() */
4379int usb_unlocked_disable_lpm(struct usb_device *udev)
4380{
4381	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4382	int ret;
4383
4384	if (!hcd)
4385		return -EINVAL;
4386
4387	mutex_lock(hcd->bandwidth_mutex);
4388	ret = usb_disable_lpm(udev);
4389	mutex_unlock(hcd->bandwidth_mutex);
4390
4391	return ret;
4392}
4393EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4394
4395/*
4396 * Attempt to enable device-initiated and hub-initiated U1 and U2 entry.  The
4397 * xHCI host policy may prevent U1 or U2 from being enabled.
4398 *
4399 * Other callers may have disabled link PM, so U1 and U2 entry will be disabled
4400 * until the lpm_disable_count drops to zero.  Caller must own the
4401 * bandwidth_mutex.
4402 */
4403void usb_enable_lpm(struct usb_device *udev)
4404{
4405	struct usb_hcd *hcd;
4406	struct usb_hub *hub;
4407	struct usb_port *port_dev;
4408
4409	if (!udev || !udev->parent ||
4410			udev->speed < USB_SPEED_SUPER ||
4411			!udev->lpm_capable ||
4412			udev->state < USB_STATE_CONFIGURED)
4413		return;
4414
4415	udev->lpm_disable_count--;
4416	hcd = bus_to_hcd(udev->bus);
4417	/* Double check that we can both enable and disable LPM.
4418	 * Device must be configured to accept set feature U1/U2 timeout.
4419	 */
4420	if (!hcd || !hcd->driver->enable_usb3_lpm_timeout ||
4421			!hcd->driver->disable_usb3_lpm_timeout)
4422		return;
4423
4424	if (udev->lpm_disable_count > 0)
4425		return;
4426
4427	hub = usb_hub_to_struct_hub(udev->parent);
4428	if (!hub)
4429		return;
4430
4431	port_dev = hub->ports[udev->portnum - 1];
4432
4433	if (port_dev->usb3_lpm_u1_permit)
4434		usb_enable_link_state(hcd, udev, USB3_LPM_U1);
4435
4436	if (port_dev->usb3_lpm_u2_permit)
4437		usb_enable_link_state(hcd, udev, USB3_LPM_U2);
4438}
4439EXPORT_SYMBOL_GPL(usb_enable_lpm);
4440
4441/* Grab the bandwidth_mutex before calling usb_enable_lpm() */
4442void usb_unlocked_enable_lpm(struct usb_device *udev)
4443{
4444	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4445
4446	if (!hcd)
4447		return;
4448
4449	mutex_lock(hcd->bandwidth_mutex);
4450	usb_enable_lpm(udev);
4451	mutex_unlock(hcd->bandwidth_mutex);
4452}
4453EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4454
4455/* usb3 devices use U3 for disabled, make sure remote wakeup is disabled */
4456static void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4457					  struct usb_port *port_dev)
4458{
4459	struct usb_device *udev = port_dev->child;
4460	int ret;
4461
4462	if (udev && udev->port_is_suspended && udev->do_remote_wakeup) {
4463		ret = hub_set_port_link_state(hub, port_dev->portnum,
4464					      USB_SS_PORT_LS_U0);
4465		if (!ret) {
4466			msleep(USB_RESUME_TIMEOUT);
4467			ret = usb_disable_remote_wakeup(udev);
4468		}
4469		if (ret)
4470			dev_warn(&udev->dev,
4471				 "Port disable: can't disable remote wake\n");
4472		udev->do_remote_wakeup = 0;
4473	}
4474}
4475
4476#else	/* CONFIG_PM */
4477
4478#define hub_suspend		NULL
4479#define hub_resume		NULL
4480#define hub_reset_resume	NULL
4481
4482static inline void hub_usb3_port_prepare_disable(struct usb_hub *hub,
4483						 struct usb_port *port_dev) { }
4484
4485int usb_disable_lpm(struct usb_device *udev)
4486{
4487	return 0;
4488}
4489EXPORT_SYMBOL_GPL(usb_disable_lpm);
4490
4491void usb_enable_lpm(struct usb_device *udev) { }
4492EXPORT_SYMBOL_GPL(usb_enable_lpm);
4493
4494int usb_unlocked_disable_lpm(struct usb_device *udev)
4495{
4496	return 0;
4497}
4498EXPORT_SYMBOL_GPL(usb_unlocked_disable_lpm);
4499
4500void usb_unlocked_enable_lpm(struct usb_device *udev) { }
4501EXPORT_SYMBOL_GPL(usb_unlocked_enable_lpm);
4502
4503int usb_disable_ltm(struct usb_device *udev)
4504{
4505	return 0;
4506}
4507EXPORT_SYMBOL_GPL(usb_disable_ltm);
4508
4509void usb_enable_ltm(struct usb_device *udev) { }
4510EXPORT_SYMBOL_GPL(usb_enable_ltm);
4511
4512static int hub_handle_remote_wakeup(struct usb_hub *hub, unsigned int port,
4513		u16 portstatus, u16 portchange)
4514{
4515	return 0;
4516}
4517
4518static int usb_req_set_sel(struct usb_device *udev)
4519{
4520	return 0;
4521}
4522
4523#endif	/* CONFIG_PM */
4524
4525/*
4526 * USB-3 does not have a similar link state as USB-2 that will avoid negotiating
4527 * a connection with a plugged-in cable but will signal the host when the cable
4528 * is unplugged. Disable remote wake and set link state to U3 for USB-3 devices
4529 */
4530static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
4531{
4532	struct usb_port *port_dev = hub->ports[port1 - 1];
4533	struct usb_device *hdev = hub->hdev;
4534	int ret = 0;
4535
4536	if (!hub->error) {
4537		if (hub_is_superspeed(hub->hdev)) {
4538			hub_usb3_port_prepare_disable(hub, port_dev);
4539			ret = hub_set_port_link_state(hub, port_dev->portnum,
4540						      USB_SS_PORT_LS_U3);
4541		} else {
4542			ret = usb_clear_port_feature(hdev, port1,
4543					USB_PORT_FEAT_ENABLE);
4544		}
4545	}
4546	if (port_dev->child && set_state)
4547		usb_set_device_state(port_dev->child, USB_STATE_NOTATTACHED);
4548	if (ret && ret != -ENODEV)
4549		dev_err(&port_dev->dev, "cannot disable (err = %d)\n", ret);
4550	return ret;
4551}
4552
4553/*
4554 * usb_port_disable - disable a usb device's upstream port
4555 * @udev: device to disable
4556 * Context: @udev locked, must be able to sleep.
4557 *
4558 * Disables a USB device that isn't in active use.
4559 */
4560int usb_port_disable(struct usb_device *udev)
4561{
4562	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4563
4564	return hub_port_disable(hub, udev->portnum, 0);
4565}
4566
4567/* USB 2.0 spec, 7.1.7.3 / fig 7-29:
4568 *
4569 * Between connect detection and reset signaling there must be a delay
4570 * of 100ms at least for debounce and power-settling.  The corresponding
4571 * timer shall restart whenever the downstream port detects a disconnect.
4572 *
4573 * Apparently there are some bluetooth and irda-dongles and a number of
4574 * low-speed devices for which this debounce period may last over a second.
4575 * Not covered by the spec - but easy to deal with.
4576 *
4577 * This implementation uses a 1500ms total debounce timeout; if the
4578 * connection isn't stable by then it returns -ETIMEDOUT.  It checks
4579 * every 25ms for transient disconnects.  When the port status has been
4580 * unchanged for 100ms it returns the port status.
4581 */
4582int hub_port_debounce(struct usb_hub *hub, int port1, bool must_be_connected)
4583{
4584	int ret;
4585	u16 portchange, portstatus;
4586	unsigned connection = 0xffff;
4587	int total_time, stable_time = 0;
4588	struct usb_port *port_dev = hub->ports[port1 - 1];
4589
4590	for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
4591		ret = usb_hub_port_status(hub, port1, &portstatus, &portchange);
4592		if (ret < 0)
4593			return ret;
4594
4595		if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
4596		     (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
4597			if (!must_be_connected ||
4598			     (connection == USB_PORT_STAT_CONNECTION))
4599				stable_time += HUB_DEBOUNCE_STEP;
4600			if (stable_time >= HUB_DEBOUNCE_STABLE)
4601				break;
4602		} else {
4603			stable_time = 0;
4604			connection = portstatus & USB_PORT_STAT_CONNECTION;
4605		}
4606
4607		if (portchange & USB_PORT_STAT_C_CONNECTION) {
4608			usb_clear_port_feature(hub->hdev, port1,
4609					USB_PORT_FEAT_C_CONNECTION);
4610		}
4611
4612		if (total_time >= HUB_DEBOUNCE_TIMEOUT)
4613			break;
4614		msleep(HUB_DEBOUNCE_STEP);
4615	}
4616
4617	dev_dbg(&port_dev->dev, "debounce total %dms stable %dms status 0x%x\n",
4618			total_time, stable_time, portstatus);
4619
4620	if (stable_time < HUB_DEBOUNCE_STABLE)
4621		return -ETIMEDOUT;
4622	return portstatus;
4623}
4624
4625void usb_ep0_reinit(struct usb_device *udev)
4626{
4627	usb_disable_endpoint(udev, 0 + USB_DIR_IN, true);
4628	usb_disable_endpoint(udev, 0 + USB_DIR_OUT, true);
4629	usb_enable_endpoint(udev, &udev->ep0, true);
4630}
4631EXPORT_SYMBOL_GPL(usb_ep0_reinit);
4632
4633#define usb_sndaddr0pipe()	(PIPE_CONTROL << 30)
4634#define usb_rcvaddr0pipe()	((PIPE_CONTROL << 30) | USB_DIR_IN)
4635
4636static int hub_set_address(struct usb_device *udev, int devnum)
4637{
4638	int retval;
4639	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4640
4641	/*
4642	 * The host controller will choose the device address,
4643	 * instead of the core having chosen it earlier
4644	 */
4645	if (!hcd->driver->address_device && devnum <= 1)
4646		return -EINVAL;
4647	if (udev->state == USB_STATE_ADDRESS)
4648		return 0;
4649	if (udev->state != USB_STATE_DEFAULT)
4650		return -EINVAL;
4651	if (hcd->driver->address_device)
4652		retval = hcd->driver->address_device(hcd, udev);
4653	else
4654		retval = usb_control_msg(udev, usb_sndaddr0pipe(),
4655				USB_REQ_SET_ADDRESS, 0, devnum, 0,
4656				NULL, 0, USB_CTRL_SET_TIMEOUT);
4657	if (retval == 0) {
4658		update_devnum(udev, devnum);
4659		/* Device now using proper address. */
4660		usb_set_device_state(udev, USB_STATE_ADDRESS);
4661		usb_ep0_reinit(udev);
4662	}
4663	return retval;
4664}
4665
4666/*
4667 * There are reports of USB 3.0 devices that say they support USB 2.0 Link PM
4668 * when they're plugged into a USB 2.0 port, but they don't work when LPM is
4669 * enabled.
4670 *
4671 * Only enable USB 2.0 Link PM if the port is internal (hardwired), or the
4672 * device says it supports the new USB 2.0 Link PM errata by setting the BESL
4673 * support bit in the BOS descriptor.
4674 */
4675static void hub_set_initial_usb2_lpm_policy(struct usb_device *udev)
4676{
4677	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
4678	int connect_type = USB_PORT_CONNECT_TYPE_UNKNOWN;
4679
4680	if (!udev->usb2_hw_lpm_capable || !udev->bos)
4681		return;
4682
4683	if (hub)
4684		connect_type = hub->ports[udev->portnum - 1]->connect_type;
4685
4686	if ((udev->bos->ext_cap->bmAttributes & cpu_to_le32(USB_BESL_SUPPORT)) ||
4687			connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
4688		udev->usb2_hw_lpm_allowed = 1;
4689		usb_enable_usb2_hardware_lpm(udev);
4690	}
4691}
4692
4693static int hub_enable_device(struct usb_device *udev)
4694{
4695	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
4696
4697	if (!hcd->driver->enable_device)
4698		return 0;
4699	if (udev->state == USB_STATE_ADDRESS)
4700		return 0;
4701	if (udev->state != USB_STATE_DEFAULT)
4702		return -EINVAL;
4703
4704	return hcd->driver->enable_device(hcd, udev);
4705}
4706
4707/* Reset device, (re)assign address, get device descriptor.
4708 * Device connection must be stable, no more debouncing needed.
4709 * Returns device in USB_STATE_ADDRESS, except on error.
4710 *
4711 * If this is called for an already-existing device (as part of
4712 * usb_reset_and_verify_device), the caller must own the device lock and
4713 * the port lock.  For a newly detected device that is not accessible
4714 * through any global pointers, it's not necessary to lock the device,
4715 * but it is still necessary to lock the port.
4716 */
4717static int
4718hub_port_init(struct usb_hub *hub, struct usb_device *udev, int port1,
4719		int retry_counter)
4720{
4721	struct usb_device	*hdev = hub->hdev;
4722	struct usb_hcd		*hcd = bus_to_hcd(hdev->bus);
4723	struct usb_port		*port_dev = hub->ports[port1 - 1];
4724	int			retries, operations, retval, i;
4725	unsigned		delay = HUB_SHORT_RESET_TIME;
4726	enum usb_device_speed	oldspeed = udev->speed;
4727	const char		*speed;
4728	int			devnum = udev->devnum;
4729	const char		*driver_name;
4730	bool			do_new_scheme;
4731
4732	/* root hub ports have a slightly longer reset period
4733	 * (from USB 2.0 spec, section 7.1.7.5)
4734	 */
4735	if (!hdev->parent) {
4736		delay = HUB_ROOT_RESET_TIME;
4737		if (port1 == hdev->bus->otg_port)
4738			hdev->bus->b_hnp_enable = 0;
4739	}
4740
4741	/* Some low speed devices have problems with the quick delay, so */
4742	/*  be a bit pessimistic with those devices. RHbug #23670 */
4743	if (oldspeed == USB_SPEED_LOW)
4744		delay = HUB_LONG_RESET_TIME;
4745
 
 
4746	/* Reset the device; full speed may morph to high speed */
4747	/* FIXME a USB 2.0 device may morph into SuperSpeed on reset. */
4748	retval = hub_port_reset(hub, port1, udev, delay, false);
4749	if (retval < 0)		/* error or disconnect */
4750		goto fail;
4751	/* success, speed is known */
4752
4753	retval = -ENODEV;
4754
4755	/* Don't allow speed changes at reset, except usb 3.0 to faster */
4756	if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed &&
4757	    !(oldspeed == USB_SPEED_SUPER && udev->speed > oldspeed)) {
4758		dev_dbg(&udev->dev, "device reset changed speed!\n");
4759		goto fail;
4760	}
4761	oldspeed = udev->speed;
4762
4763	/* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
4764	 * it's fixed size except for full speed devices.
4765	 * For Wireless USB devices, ep0 max packet is always 512 (tho
4766	 * reported as 0xff in the device descriptor). WUSB1.0[4.8.1].
4767	 */
4768	switch (udev->speed) {
4769	case USB_SPEED_SUPER_PLUS:
4770	case USB_SPEED_SUPER:
4771	case USB_SPEED_WIRELESS:	/* fixed at 512 */
4772		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(512);
4773		break;
4774	case USB_SPEED_HIGH:		/* fixed at 64 */
4775		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4776		break;
4777	case USB_SPEED_FULL:		/* 8, 16, 32, or 64 */
4778		/* to determine the ep0 maxpacket size, try to read
4779		 * the device descriptor to get bMaxPacketSize0 and
4780		 * then correct our initial guess.
4781		 */
4782		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
4783		break;
4784	case USB_SPEED_LOW:		/* fixed at 8 */
4785		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(8);
4786		break;
4787	default:
4788		goto fail;
4789	}
4790
4791	if (udev->speed == USB_SPEED_WIRELESS)
4792		speed = "variable speed Wireless";
4793	else
4794		speed = usb_speed_string(udev->speed);
4795
4796	/*
4797	 * The controller driver may be NULL if the controller device
4798	 * is the middle device between platform device and roothub.
4799	 * This middle device may not need a device driver due to
4800	 * all hardware control can be at platform device driver, this
4801	 * platform device is usually a dual-role USB controller device.
4802	 */
4803	if (udev->bus->controller->driver)
4804		driver_name = udev->bus->controller->driver->name;
4805	else
4806		driver_name = udev->bus->sysdev->driver->name;
4807
4808	if (udev->speed < USB_SPEED_SUPER)
4809		dev_info(&udev->dev,
4810				"%s %s USB device number %d using %s\n",
4811				(udev->config) ? "reset" : "new", speed,
4812				devnum, driver_name);
4813
4814	/* Set up TT records, if needed  */
4815	if (hdev->tt) {
4816		udev->tt = hdev->tt;
4817		udev->ttport = hdev->ttport;
4818	} else if (udev->speed != USB_SPEED_HIGH
4819			&& hdev->speed == USB_SPEED_HIGH) {
4820		if (!hub->tt.hub) {
4821			dev_err(&udev->dev, "parent hub has no TT\n");
4822			retval = -EINVAL;
4823			goto fail;
4824		}
4825		udev->tt = &hub->tt;
4826		udev->ttport = port1;
4827	}
4828
4829	/* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
4830	 * Because device hardware and firmware is sometimes buggy in
4831	 * this area, and this is how Linux has done it for ages.
4832	 * Change it cautiously.
4833	 *
4834	 * NOTE:  If use_new_scheme() is true we will start by issuing
4835	 * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
4836	 * so it may help with some non-standards-compliant devices.
4837	 * Otherwise we start with SET_ADDRESS and then try to read the
4838	 * first 8 bytes of the device descriptor to get the ep0 maxpacket
4839	 * value.
4840	 */
4841	do_new_scheme = use_new_scheme(udev, retry_counter, port_dev);
4842
4843	for (retries = 0; retries < GET_DESCRIPTOR_TRIES; (++retries, msleep(100))) {
4844		if (hub_port_stop_enumerate(hub, port1, retries)) {
4845			retval = -ENODEV;
4846			break;
4847		}
4848
4849		if (do_new_scheme) {
4850			struct usb_device_descriptor *buf;
4851			int r = 0;
4852
 
4853			retval = hub_enable_device(udev);
4854			if (retval < 0) {
4855				dev_err(&udev->dev,
4856					"hub failed to enable device, error %d\n",
4857					retval);
4858				goto fail;
4859			}
4860
4861#define GET_DESCRIPTOR_BUFSIZE	64
4862			buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
4863			if (!buf) {
4864				retval = -ENOMEM;
4865				continue;
4866			}
4867
4868			/* Retry on all errors; some devices are flakey.
4869			 * 255 is for WUSB devices, we actually need to use
4870			 * 512 (WUSB1.0[4.8.1]).
4871			 */
4872			for (operations = 0; operations < GET_MAXPACKET0_TRIES;
4873					++operations) {
4874				buf->bMaxPacketSize0 = 0;
4875				r = usb_control_msg(udev, usb_rcvaddr0pipe(),
4876					USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
4877					USB_DT_DEVICE << 8, 0,
4878					buf, GET_DESCRIPTOR_BUFSIZE,
4879					initial_descriptor_timeout);
4880				switch (buf->bMaxPacketSize0) {
4881				case 8: case 16: case 32: case 64: case 255:
4882					if (buf->bDescriptorType ==
4883							USB_DT_DEVICE) {
4884						r = 0;
4885						break;
4886					}
4887					fallthrough;
4888				default:
4889					if (r == 0)
4890						r = -EPROTO;
4891					break;
4892				}
4893				/*
4894				 * Some devices time out if they are powered on
4895				 * when already connected. They need a second
4896				 * reset. But only on the first attempt,
4897				 * lest we get into a time out/reset loop
4898				 */
4899				if (r == 0 || (r == -ETIMEDOUT &&
4900						retries == 0 &&
4901						udev->speed > USB_SPEED_FULL))
4902					break;
4903			}
4904			udev->descriptor.bMaxPacketSize0 =
4905					buf->bMaxPacketSize0;
4906			kfree(buf);
4907
4908			retval = hub_port_reset(hub, port1, udev, delay, false);
4909			if (retval < 0)		/* error or disconnect */
4910				goto fail;
4911			if (oldspeed != udev->speed) {
4912				dev_dbg(&udev->dev,
4913					"device reset changed speed!\n");
4914				retval = -ENODEV;
4915				goto fail;
4916			}
4917			if (r) {
4918				if (r != -ENODEV)
4919					dev_err(&udev->dev, "device descriptor read/64, error %d\n",
4920							r);
4921				retval = -EMSGSIZE;
4922				continue;
4923			}
4924#undef GET_DESCRIPTOR_BUFSIZE
4925		}
4926
4927		/*
4928		 * If device is WUSB, we already assigned an
4929		 * unauthorized address in the Connect Ack sequence;
4930		 * authorization will assign the final address.
4931		 */
4932		if (udev->wusb == 0) {
4933			for (operations = 0; operations < SET_ADDRESS_TRIES; ++operations) {
4934				retval = hub_set_address(udev, devnum);
4935				if (retval >= 0)
4936					break;
4937				msleep(200);
4938			}
4939			if (retval < 0) {
4940				if (retval != -ENODEV)
4941					dev_err(&udev->dev, "device not accepting address %d, error %d\n",
4942							devnum, retval);
4943				goto fail;
4944			}
4945			if (udev->speed >= USB_SPEED_SUPER) {
4946				devnum = udev->devnum;
4947				dev_info(&udev->dev,
4948						"%s SuperSpeed%s%s USB device number %d using %s\n",
4949						(udev->config) ? "reset" : "new",
4950					 (udev->speed == USB_SPEED_SUPER_PLUS) ?
4951							" Plus" : "",
4952					 (udev->ssp_rate == USB_SSP_GEN_2x2) ?
4953							" Gen 2x2" :
4954					 (udev->ssp_rate == USB_SSP_GEN_2x1) ?
4955							" Gen 2x1" :
4956					 (udev->ssp_rate == USB_SSP_GEN_1x2) ?
4957							" Gen 1x2" : "",
4958					 devnum, driver_name);
4959			}
4960
4961			/* cope with hardware quirkiness:
4962			 *  - let SET_ADDRESS settle, some device hardware wants it
4963			 *  - read ep0 maxpacket even for high and low speed,
4964			 */
4965			msleep(10);
4966			if (do_new_scheme)
 
 
 
 
4967				break;
4968		}
4969
4970		retval = usb_get_device_descriptor(udev, 8);
4971		if (retval < 8) {
4972			if (retval != -ENODEV)
4973				dev_err(&udev->dev,
4974					"device descriptor read/8, error %d\n",
4975					retval);
4976			if (retval >= 0)
4977				retval = -EMSGSIZE;
4978		} else {
4979			u32 delay;
4980
4981			retval = 0;
4982
4983			delay = udev->parent->hub_delay;
4984			udev->hub_delay = min_t(u32, delay,
4985						USB_TP_TRANSMISSION_DELAY_MAX);
4986			retval = usb_set_isoch_delay(udev);
4987			if (retval) {
4988				dev_dbg(&udev->dev,
4989					"Failed set isoch delay, error %d\n",
4990					retval);
4991				retval = 0;
4992			}
4993			break;
4994		}
4995	}
4996	if (retval)
4997		goto fail;
4998
4999	/*
5000	 * Some superspeed devices have finished the link training process
5001	 * and attached to a superspeed hub port, but the device descriptor
5002	 * got from those devices show they aren't superspeed devices. Warm
5003	 * reset the port attached by the devices can fix them.
5004	 */
5005	if ((udev->speed >= USB_SPEED_SUPER) &&
5006			(le16_to_cpu(udev->descriptor.bcdUSB) < 0x0300)) {
5007		dev_err(&udev->dev, "got a wrong device descriptor, "
5008				"warm reset device\n");
5009		hub_port_reset(hub, port1, udev,
5010				HUB_BH_RESET_TIME, true);
5011		retval = -EINVAL;
5012		goto fail;
5013	}
5014
5015	if (udev->descriptor.bMaxPacketSize0 == 0xff ||
5016			udev->speed >= USB_SPEED_SUPER)
5017		i = 512;
5018	else
5019		i = udev->descriptor.bMaxPacketSize0;
5020	if (usb_endpoint_maxp(&udev->ep0.desc) != i) {
5021		if (udev->speed == USB_SPEED_LOW ||
5022				!(i == 8 || i == 16 || i == 32 || i == 64)) {
5023			dev_err(&udev->dev, "Invalid ep0 maxpacket: %d\n", i);
5024			retval = -EMSGSIZE;
5025			goto fail;
5026		}
5027		if (udev->speed == USB_SPEED_FULL)
5028			dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
5029		else
5030			dev_warn(&udev->dev, "Using ep0 maxpacket: %d\n", i);
5031		udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
5032		usb_ep0_reinit(udev);
5033	}
5034
5035	retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
5036	if (retval < (signed)sizeof(udev->descriptor)) {
5037		if (retval != -ENODEV)
5038			dev_err(&udev->dev, "device descriptor read/all, error %d\n",
5039					retval);
5040		if (retval >= 0)
5041			retval = -ENOMSG;
5042		goto fail;
5043	}
5044
5045	usb_detect_quirks(udev);
5046
5047	if (udev->wusb == 0 && le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0201) {
5048		retval = usb_get_bos_descriptor(udev);
5049		if (!retval) {
5050			udev->lpm_capable = usb_device_supports_lpm(udev);
5051			udev->lpm_disable_count = 1;
5052			usb_set_lpm_parameters(udev);
5053			usb_req_set_sel(udev);
5054		}
5055	}
5056
5057	retval = 0;
5058	/* notify HCD that we have a device connected and addressed */
5059	if (hcd->driver->update_device)
5060		hcd->driver->update_device(hcd, udev);
5061	hub_set_initial_usb2_lpm_policy(udev);
5062fail:
5063	if (retval) {
5064		hub_port_disable(hub, port1, 0);
5065		update_devnum(udev, devnum);	/* for disconnect processing */
5066	}
 
5067	return retval;
5068}
5069
5070static void
5071check_highspeed(struct usb_hub *hub, struct usb_device *udev, int port1)
5072{
5073	struct usb_qualifier_descriptor	*qual;
5074	int				status;
5075
5076	if (udev->quirks & USB_QUIRK_DEVICE_QUALIFIER)
5077		return;
5078
5079	qual = kmalloc(sizeof *qual, GFP_KERNEL);
5080	if (qual == NULL)
5081		return;
5082
5083	status = usb_get_descriptor(udev, USB_DT_DEVICE_QUALIFIER, 0,
5084			qual, sizeof *qual);
5085	if (status == sizeof *qual) {
5086		dev_info(&udev->dev, "not running at top speed; "
5087			"connect to a high speed hub\n");
5088		/* hub LEDs are probably harder to miss than syslog */
5089		if (hub->has_indicators) {
5090			hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
5091			queue_delayed_work(system_power_efficient_wq,
5092					&hub->leds, 0);
5093		}
5094	}
5095	kfree(qual);
5096}
5097
5098static unsigned
5099hub_power_remaining(struct usb_hub *hub)
5100{
5101	struct usb_device *hdev = hub->hdev;
5102	int remaining;
5103	int port1;
5104
5105	if (!hub->limited_power)
5106		return 0;
5107
5108	remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
5109	for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
5110		struct usb_port *port_dev = hub->ports[port1 - 1];
5111		struct usb_device *udev = port_dev->child;
5112		unsigned unit_load;
5113		int delta;
5114
5115		if (!udev)
5116			continue;
5117		if (hub_is_superspeed(udev))
5118			unit_load = 150;
5119		else
5120			unit_load = 100;
5121
5122		/*
5123		 * Unconfigured devices may not use more than one unit load,
5124		 * or 8mA for OTG ports
5125		 */
5126		if (udev->actconfig)
5127			delta = usb_get_max_power(udev, udev->actconfig);
5128		else if (port1 != udev->bus->otg_port || hdev->parent)
5129			delta = unit_load;
5130		else
5131			delta = 8;
5132		if (delta > hub->mA_per_port)
5133			dev_warn(&port_dev->dev, "%dmA is over %umA budget!\n",
5134					delta, hub->mA_per_port);
5135		remaining -= delta;
5136	}
5137	if (remaining < 0) {
5138		dev_warn(hub->intfdev, "%dmA over power budget!\n",
5139			-remaining);
5140		remaining = 0;
5141	}
5142	return remaining;
5143}
5144
5145
5146static int descriptors_changed(struct usb_device *udev,
5147		struct usb_device_descriptor *old_device_descriptor,
5148		struct usb_host_bos *old_bos)
5149{
5150	int		changed = 0;
5151	unsigned	index;
5152	unsigned	serial_len = 0;
5153	unsigned	len;
5154	unsigned	old_length;
5155	int		length;
5156	char		*buf;
5157
5158	if (memcmp(&udev->descriptor, old_device_descriptor,
5159			sizeof(*old_device_descriptor)) != 0)
5160		return 1;
5161
5162	if ((old_bos && !udev->bos) || (!old_bos && udev->bos))
5163		return 1;
5164	if (udev->bos) {
5165		len = le16_to_cpu(udev->bos->desc->wTotalLength);
5166		if (len != le16_to_cpu(old_bos->desc->wTotalLength))
5167			return 1;
5168		if (memcmp(udev->bos->desc, old_bos->desc, len))
5169			return 1;
5170	}
5171
5172	/* Since the idVendor, idProduct, and bcdDevice values in the
5173	 * device descriptor haven't changed, we will assume the
5174	 * Manufacturer and Product strings haven't changed either.
5175	 * But the SerialNumber string could be different (e.g., a
5176	 * different flash card of the same brand).
5177	 */
5178	if (udev->serial)
5179		serial_len = strlen(udev->serial) + 1;
5180
5181	len = serial_len;
5182	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5183		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5184		len = max(len, old_length);
5185	}
5186
5187	buf = kmalloc(len, GFP_NOIO);
5188	if (!buf)
5189		/* assume the worst */
5190		return 1;
5191
5192	for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
5193		old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
5194		length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
5195				old_length);
5196		if (length != old_length) {
5197			dev_dbg(&udev->dev, "config index %d, error %d\n",
5198					index, length);
5199			changed = 1;
5200			break;
5201		}
5202		if (memcmp(buf, udev->rawdescriptors[index], old_length)
5203				!= 0) {
5204			dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
5205				index,
5206				((struct usb_config_descriptor *) buf)->
5207					bConfigurationValue);
5208			changed = 1;
5209			break;
5210		}
5211	}
5212
5213	if (!changed && serial_len) {
5214		length = usb_string(udev, udev->descriptor.iSerialNumber,
5215				buf, serial_len);
5216		if (length + 1 != serial_len) {
5217			dev_dbg(&udev->dev, "serial string error %d\n",
5218					length);
5219			changed = 1;
5220		} else if (memcmp(buf, udev->serial, length) != 0) {
5221			dev_dbg(&udev->dev, "serial string changed\n");
5222			changed = 1;
5223		}
5224	}
5225
5226	kfree(buf);
5227	return changed;
5228}
5229
5230static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus,
5231		u16 portchange)
5232{
5233	int status = -ENODEV;
5234	int i;
5235	unsigned unit_load;
5236	struct usb_device *hdev = hub->hdev;
5237	struct usb_hcd *hcd = bus_to_hcd(hdev->bus);
5238	struct usb_port *port_dev = hub->ports[port1 - 1];
5239	struct usb_device *udev = port_dev->child;
5240	static int unreliable_port = -1;
5241	bool retry_locked;
5242
5243	/* Disconnect any existing devices under this port */
5244	if (udev) {
5245		if (hcd->usb_phy && !hdev->parent)
5246			usb_phy_notify_disconnect(hcd->usb_phy, udev->speed);
5247		usb_disconnect(&port_dev->child);
5248	}
5249
5250	/* We can forget about a "removed" device when there's a physical
5251	 * disconnect or the connect status changes.
5252	 */
5253	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5254			(portchange & USB_PORT_STAT_C_CONNECTION))
5255		clear_bit(port1, hub->removed_bits);
5256
5257	if (portchange & (USB_PORT_STAT_C_CONNECTION |
5258				USB_PORT_STAT_C_ENABLE)) {
5259		status = hub_port_debounce_be_stable(hub, port1);
5260		if (status < 0) {
5261			if (status != -ENODEV &&
5262				port1 != unreliable_port &&
5263				printk_ratelimit())
5264				dev_err(&port_dev->dev, "connect-debounce failed\n");
5265			portstatus &= ~USB_PORT_STAT_CONNECTION;
5266			unreliable_port = port1;
5267		} else {
5268			portstatus = status;
5269		}
5270	}
5271
5272	/* Return now if debouncing failed or nothing is connected or
5273	 * the device was "removed".
5274	 */
5275	if (!(portstatus & USB_PORT_STAT_CONNECTION) ||
5276			test_bit(port1, hub->removed_bits)) {
5277
5278		/*
5279		 * maybe switch power back on (e.g. root hub was reset)
5280		 * but only if the port isn't owned by someone else.
5281		 */
5282		if (hub_is_port_power_switchable(hub)
5283				&& !usb_port_is_power_on(hub, portstatus)
5284				&& !port_dev->port_owner)
5285			set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
5286
5287		if (portstatus & USB_PORT_STAT_ENABLE)
5288			goto done;
5289		return;
5290	}
5291	if (hub_is_superspeed(hub->hdev))
5292		unit_load = 150;
5293	else
5294		unit_load = 100;
5295
5296	status = 0;
 
5297
5298	for (i = 0; i < PORT_INIT_TRIES; i++) {
5299		if (hub_port_stop_enumerate(hub, port1, i)) {
5300			status = -ENODEV;
5301			break;
5302		}
5303
5304		usb_lock_port(port_dev);
5305		mutex_lock(hcd->address0_mutex);
5306		retry_locked = true;
5307		/* reallocate for each attempt, since references
5308		 * to the previous one can escape in various ways
5309		 */
5310		udev = usb_alloc_dev(hdev, hdev->bus, port1);
5311		if (!udev) {
5312			dev_err(&port_dev->dev,
5313					"couldn't allocate usb_device\n");
5314			mutex_unlock(hcd->address0_mutex);
5315			usb_unlock_port(port_dev);
5316			goto done;
5317		}
5318
5319		usb_set_device_state(udev, USB_STATE_POWERED);
5320		udev->bus_mA = hub->mA_per_port;
5321		udev->level = hdev->level + 1;
5322		udev->wusb = hub_is_wusb(hub);
5323
5324		/* Devices connected to SuperSpeed hubs are USB 3.0 or later */
5325		if (hub_is_superspeed(hub->hdev))
5326			udev->speed = USB_SPEED_SUPER;
5327		else
5328			udev->speed = USB_SPEED_UNKNOWN;
5329
5330		choose_devnum(udev);
5331		if (udev->devnum <= 0) {
5332			status = -ENOTCONN;	/* Don't retry */
5333			goto loop;
5334		}
5335
5336		/* reset (non-USB 3.0 devices) and get descriptor */
 
5337		status = hub_port_init(hub, udev, port1, i);
 
5338		if (status < 0)
5339			goto loop;
5340
5341		mutex_unlock(hcd->address0_mutex);
5342		usb_unlock_port(port_dev);
5343		retry_locked = false;
5344
5345		if (udev->quirks & USB_QUIRK_DELAY_INIT)
5346			msleep(2000);
5347
5348		/* consecutive bus-powered hubs aren't reliable; they can
5349		 * violate the voltage drop budget.  if the new child has
5350		 * a "powered" LED, users should notice we didn't enable it
5351		 * (without reading syslog), even without per-port LEDs
5352		 * on the parent.
5353		 */
5354		if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
5355				&& udev->bus_mA <= unit_load) {
5356			u16	devstat;
5357
5358			status = usb_get_std_status(udev, USB_RECIP_DEVICE, 0,
5359					&devstat);
5360			if (status) {
5361				dev_dbg(&udev->dev, "get status %d ?\n", status);
5362				goto loop_disable;
5363			}
5364			if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
5365				dev_err(&udev->dev,
5366					"can't connect bus-powered hub "
5367					"to this port\n");
5368				if (hub->has_indicators) {
5369					hub->indicator[port1-1] =
5370						INDICATOR_AMBER_BLINK;
5371					queue_delayed_work(
5372						system_power_efficient_wq,
5373						&hub->leds, 0);
5374				}
5375				status = -ENOTCONN;	/* Don't retry */
5376				goto loop_disable;
5377			}
5378		}
5379
5380		/* check for devices running slower than they could */
5381		if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
5382				&& udev->speed == USB_SPEED_FULL
5383				&& highspeed_hubs != 0)
5384			check_highspeed(hub, udev, port1);
5385
5386		/* Store the parent's children[] pointer.  At this point
5387		 * udev becomes globally accessible, although presumably
5388		 * no one will look at it until hdev is unlocked.
5389		 */
5390		status = 0;
5391
5392		mutex_lock(&usb_port_peer_mutex);
5393
5394		/* We mustn't add new devices if the parent hub has
5395		 * been disconnected; we would race with the
5396		 * recursively_mark_NOTATTACHED() routine.
5397		 */
5398		spin_lock_irq(&device_state_lock);
5399		if (hdev->state == USB_STATE_NOTATTACHED)
5400			status = -ENOTCONN;
5401		else
5402			port_dev->child = udev;
5403		spin_unlock_irq(&device_state_lock);
5404		mutex_unlock(&usb_port_peer_mutex);
5405
5406		/* Run it through the hoops (find a driver, etc) */
5407		if (!status) {
5408			status = usb_new_device(udev);
5409			if (status) {
5410				mutex_lock(&usb_port_peer_mutex);
5411				spin_lock_irq(&device_state_lock);
5412				port_dev->child = NULL;
5413				spin_unlock_irq(&device_state_lock);
5414				mutex_unlock(&usb_port_peer_mutex);
5415			} else {
5416				if (hcd->usb_phy && !hdev->parent)
5417					usb_phy_notify_connect(hcd->usb_phy,
5418							udev->speed);
5419			}
5420		}
5421
5422		if (status)
5423			goto loop_disable;
5424
5425		status = hub_power_remaining(hub);
5426		if (status)
5427			dev_dbg(hub->intfdev, "%dmA power budget left\n", status);
5428
5429		return;
5430
5431loop_disable:
5432		hub_port_disable(hub, port1, 1);
5433loop:
5434		usb_ep0_reinit(udev);
5435		release_devnum(udev);
5436		hub_free_dev(udev);
5437		if (retry_locked) {
5438			mutex_unlock(hcd->address0_mutex);
5439			usb_unlock_port(port_dev);
5440		}
5441		usb_put_dev(udev);
5442		if ((status == -ENOTCONN) || (status == -ENOTSUPP))
5443			break;
5444
5445		/* When halfway through our retry count, power-cycle the port */
5446		if (i == (PORT_INIT_TRIES - 1) / 2) {
5447			dev_info(&port_dev->dev, "attempt power cycle\n");
5448			usb_hub_set_port_power(hdev, hub, port1, false);
5449			msleep(2 * hub_power_on_good_delay(hub));
5450			usb_hub_set_port_power(hdev, hub, port1, true);
5451			msleep(hub_power_on_good_delay(hub));
5452		}
5453	}
5454	if (hub->hdev->parent ||
5455			!hcd->driver->port_handed_over ||
5456			!(hcd->driver->port_handed_over)(hcd, port1)) {
5457		if (status != -ENOTCONN && status != -ENODEV)
5458			dev_err(&port_dev->dev,
5459					"unable to enumerate USB device\n");
5460	}
5461
5462done:
5463	hub_port_disable(hub, port1, 1);
5464	if (hcd->driver->relinquish_port && !hub->hdev->parent) {
5465		if (status != -ENOTCONN && status != -ENODEV)
5466			hcd->driver->relinquish_port(hcd, port1);
5467	}
5468}
5469
5470/* Handle physical or logical connection change events.
5471 * This routine is called when:
5472 *	a port connection-change occurs;
5473 *	a port enable-change occurs (often caused by EMI);
5474 *	usb_reset_and_verify_device() encounters changed descriptors (as from
5475 *		a firmware download)
5476 * caller already locked the hub
5477 */
5478static void hub_port_connect_change(struct usb_hub *hub, int port1,
5479					u16 portstatus, u16 portchange)
5480		__must_hold(&port_dev->status_lock)
5481{
5482	struct usb_port *port_dev = hub->ports[port1 - 1];
5483	struct usb_device *udev = port_dev->child;
5484	struct usb_device_descriptor descriptor;
5485	int status = -ENODEV;
5486	int retval;
5487
5488	dev_dbg(&port_dev->dev, "status %04x, change %04x, %s\n", portstatus,
5489			portchange, portspeed(hub, portstatus));
5490
5491	if (hub->has_indicators) {
5492		set_port_led(hub, port1, HUB_LED_AUTO);
5493		hub->indicator[port1-1] = INDICATOR_AUTO;
5494	}
5495
5496#ifdef	CONFIG_USB_OTG
5497	/* during HNP, don't repeat the debounce */
5498	if (hub->hdev->bus->is_b_host)
5499		portchange &= ~(USB_PORT_STAT_C_CONNECTION |
5500				USB_PORT_STAT_C_ENABLE);
5501#endif
5502
5503	/* Try to resuscitate an existing device */
5504	if ((portstatus & USB_PORT_STAT_CONNECTION) && udev &&
5505			udev->state != USB_STATE_NOTATTACHED) {
5506		if (portstatus & USB_PORT_STAT_ENABLE) {
5507			/*
5508			 * USB-3 connections are initialized automatically by
5509			 * the hostcontroller hardware. Therefore check for
5510			 * changed device descriptors before resuscitating the
5511			 * device.
5512			 */
5513			descriptor = udev->descriptor;
5514			retval = usb_get_device_descriptor(udev,
5515					sizeof(udev->descriptor));
5516			if (retval < 0) {
5517				dev_dbg(&udev->dev,
5518						"can't read device descriptor %d\n",
5519						retval);
5520			} else {
5521				if (descriptors_changed(udev, &descriptor,
5522						udev->bos)) {
5523					dev_dbg(&udev->dev,
5524							"device descriptor has changed\n");
5525					/* for disconnect() calls */
5526					udev->descriptor = descriptor;
5527				} else {
5528					status = 0; /* Nothing to do */
5529				}
5530			}
5531#ifdef CONFIG_PM
5532		} else if (udev->state == USB_STATE_SUSPENDED &&
5533				udev->persist_enabled) {
5534			/* For a suspended device, treat this as a
5535			 * remote wakeup event.
5536			 */
5537			usb_unlock_port(port_dev);
5538			status = usb_remote_wakeup(udev);
5539			usb_lock_port(port_dev);
5540#endif
5541		} else {
5542			/* Don't resuscitate */;
5543		}
5544	}
5545	clear_bit(port1, hub->change_bits);
5546
5547	/* successfully revalidated the connection */
5548	if (status == 0)
5549		return;
5550
5551	usb_unlock_port(port_dev);
5552	hub_port_connect(hub, port1, portstatus, portchange);
5553	usb_lock_port(port_dev);
5554}
5555
5556/* Handle notifying userspace about hub over-current events */
5557static void port_over_current_notify(struct usb_port *port_dev)
5558{
5559	char *envp[3] = { NULL, NULL, NULL };
5560	struct device *hub_dev;
5561	char *port_dev_path;
5562
5563	sysfs_notify(&port_dev->dev.kobj, NULL, "over_current_count");
5564
5565	hub_dev = port_dev->dev.parent;
5566
5567	if (!hub_dev)
5568		return;
5569
5570	port_dev_path = kobject_get_path(&port_dev->dev.kobj, GFP_KERNEL);
5571	if (!port_dev_path)
5572		return;
5573
5574	envp[0] = kasprintf(GFP_KERNEL, "OVER_CURRENT_PORT=%s", port_dev_path);
5575	if (!envp[0])
5576		goto exit;
5577
5578	envp[1] = kasprintf(GFP_KERNEL, "OVER_CURRENT_COUNT=%u",
5579			port_dev->over_current_count);
5580	if (!envp[1])
5581		goto exit;
5582
5583	kobject_uevent_env(&hub_dev->kobj, KOBJ_CHANGE, envp);
5584
5585exit:
5586	kfree(envp[1]);
5587	kfree(envp[0]);
5588	kfree(port_dev_path);
5589}
5590
5591static void port_event(struct usb_hub *hub, int port1)
5592		__must_hold(&port_dev->status_lock)
5593{
5594	int connect_change;
5595	struct usb_port *port_dev = hub->ports[port1 - 1];
5596	struct usb_device *udev = port_dev->child;
5597	struct usb_device *hdev = hub->hdev;
5598	u16 portstatus, portchange;
5599	int i = 0;
5600
5601	connect_change = test_bit(port1, hub->change_bits);
5602	clear_bit(port1, hub->event_bits);
5603	clear_bit(port1, hub->wakeup_bits);
5604
5605	if (usb_hub_port_status(hub, port1, &portstatus, &portchange) < 0)
5606		return;
5607
5608	if (portchange & USB_PORT_STAT_C_CONNECTION) {
5609		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_CONNECTION);
5610		connect_change = 1;
5611	}
5612
5613	if (portchange & USB_PORT_STAT_C_ENABLE) {
5614		if (!connect_change)
5615			dev_dbg(&port_dev->dev, "enable change, status %08x\n",
5616					portstatus);
5617		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_ENABLE);
5618
5619		/*
5620		 * EM interference sometimes causes badly shielded USB devices
5621		 * to be shutdown by the hub, this hack enables them again.
5622		 * Works at least with mouse driver.
5623		 */
5624		if (!(portstatus & USB_PORT_STAT_ENABLE)
5625		    && !connect_change && udev) {
5626			dev_err(&port_dev->dev, "disabled by hub (EMI?), re-enabling...\n");
5627			connect_change = 1;
5628		}
5629	}
5630
5631	if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
5632		u16 status = 0, unused;
5633		port_dev->over_current_count++;
5634		port_over_current_notify(port_dev);
5635
5636		dev_dbg(&port_dev->dev, "over-current change #%u\n",
5637			port_dev->over_current_count);
5638		usb_clear_port_feature(hdev, port1,
5639				USB_PORT_FEAT_C_OVER_CURRENT);
5640		msleep(100);	/* Cool down */
5641		hub_power_on(hub, true);
5642		usb_hub_port_status(hub, port1, &status, &unused);
5643		if (status & USB_PORT_STAT_OVERCURRENT)
5644			dev_err(&port_dev->dev, "over-current condition\n");
5645	}
5646
5647	if (portchange & USB_PORT_STAT_C_RESET) {
5648		dev_dbg(&port_dev->dev, "reset change\n");
5649		usb_clear_port_feature(hdev, port1, USB_PORT_FEAT_C_RESET);
5650	}
5651	if ((portchange & USB_PORT_STAT_C_BH_RESET)
5652	    && hub_is_superspeed(hdev)) {
5653		dev_dbg(&port_dev->dev, "warm reset change\n");
5654		usb_clear_port_feature(hdev, port1,
5655				USB_PORT_FEAT_C_BH_PORT_RESET);
5656	}
5657	if (portchange & USB_PORT_STAT_C_LINK_STATE) {
5658		dev_dbg(&port_dev->dev, "link state change\n");
5659		usb_clear_port_feature(hdev, port1,
5660				USB_PORT_FEAT_C_PORT_LINK_STATE);
5661	}
5662	if (portchange & USB_PORT_STAT_C_CONFIG_ERROR) {
5663		dev_warn(&port_dev->dev, "config error\n");
5664		usb_clear_port_feature(hdev, port1,
5665				USB_PORT_FEAT_C_PORT_CONFIG_ERROR);
5666	}
5667
5668	/* skip port actions that require the port to be powered on */
5669	if (!pm_runtime_active(&port_dev->dev))
5670		return;
5671
5672	/* skip port actions if ignore_event and early_stop are true */
5673	if (port_dev->ignore_event && port_dev->early_stop)
5674		return;
5675
5676	if (hub_handle_remote_wakeup(hub, port1, portstatus, portchange))
5677		connect_change = 1;
5678
5679	/*
5680	 * Avoid trying to recover a USB3 SS.Inactive port with a warm reset if
5681	 * the device was disconnected. A 12ms disconnect detect timer in
5682	 * SS.Inactive state transitions the port to RxDetect automatically.
5683	 * SS.Inactive link error state is common during device disconnect.
5684	 */
5685	while (hub_port_warm_reset_required(hub, port1, portstatus)) {
5686		if ((i++ < DETECT_DISCONNECT_TRIES) && udev) {
5687			u16 unused;
5688
5689			msleep(20);
5690			usb_hub_port_status(hub, port1, &portstatus, &unused);
5691			dev_dbg(&port_dev->dev, "Wait for inactive link disconnect detect\n");
5692			continue;
5693		} else if (!udev || !(portstatus & USB_PORT_STAT_CONNECTION)
5694				|| udev->state == USB_STATE_NOTATTACHED) {
5695			dev_dbg(&port_dev->dev, "do warm reset, port only\n");
5696			if (hub_port_reset(hub, port1, NULL,
5697					HUB_BH_RESET_TIME, true) < 0)
5698				hub_port_disable(hub, port1, 1);
5699		} else {
5700			dev_dbg(&port_dev->dev, "do warm reset, full device\n");
5701			usb_unlock_port(port_dev);
5702			usb_lock_device(udev);
5703			usb_reset_device(udev);
5704			usb_unlock_device(udev);
5705			usb_lock_port(port_dev);
5706			connect_change = 0;
5707		}
5708		break;
5709	}
5710
5711	if (connect_change)
5712		hub_port_connect_change(hub, port1, portstatus, portchange);
5713}
5714
5715static void hub_event(struct work_struct *work)
5716{
5717	struct usb_device *hdev;
5718	struct usb_interface *intf;
5719	struct usb_hub *hub;
5720	struct device *hub_dev;
5721	u16 hubstatus;
5722	u16 hubchange;
5723	int i, ret;
5724
5725	hub = container_of(work, struct usb_hub, events);
5726	hdev = hub->hdev;
5727	hub_dev = hub->intfdev;
5728	intf = to_usb_interface(hub_dev);
5729
5730	kcov_remote_start_usb((u64)hdev->bus->busnum);
5731
5732	dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x\n",
5733			hdev->state, hdev->maxchild,
5734			/* NOTE: expects max 15 ports... */
5735			(u16) hub->change_bits[0],
5736			(u16) hub->event_bits[0]);
5737
5738	/* Lock the device, then check to see if we were
5739	 * disconnected while waiting for the lock to succeed. */
5740	usb_lock_device(hdev);
5741	if (unlikely(hub->disconnected))
5742		goto out_hdev_lock;
5743
5744	/* If the hub has died, clean up after it */
5745	if (hdev->state == USB_STATE_NOTATTACHED) {
5746		hub->error = -ENODEV;
5747		hub_quiesce(hub, HUB_DISCONNECT);
5748		goto out_hdev_lock;
5749	}
5750
5751	/* Autoresume */
5752	ret = usb_autopm_get_interface(intf);
5753	if (ret) {
5754		dev_dbg(hub_dev, "Can't autoresume: %d\n", ret);
5755		goto out_hdev_lock;
5756	}
5757
5758	/* If this is an inactive hub, do nothing */
5759	if (hub->quiescing)
5760		goto out_autopm;
5761
5762	if (hub->error) {
5763		dev_dbg(hub_dev, "resetting for error %d\n", hub->error);
5764
5765		ret = usb_reset_device(hdev);
5766		if (ret) {
5767			dev_dbg(hub_dev, "error resetting hub: %d\n", ret);
5768			goto out_autopm;
5769		}
5770
5771		hub->nerrors = 0;
5772		hub->error = 0;
5773	}
5774
5775	/* deal with port status changes */
5776	for (i = 1; i <= hdev->maxchild; i++) {
5777		struct usb_port *port_dev = hub->ports[i - 1];
5778
5779		if (test_bit(i, hub->event_bits)
5780				|| test_bit(i, hub->change_bits)
5781				|| test_bit(i, hub->wakeup_bits)) {
5782			/*
5783			 * The get_noresume and barrier ensure that if
5784			 * the port was in the process of resuming, we
5785			 * flush that work and keep the port active for
5786			 * the duration of the port_event().  However,
5787			 * if the port is runtime pm suspended
5788			 * (powered-off), we leave it in that state, run
5789			 * an abbreviated port_event(), and move on.
5790			 */
5791			pm_runtime_get_noresume(&port_dev->dev);
5792			pm_runtime_barrier(&port_dev->dev);
5793			usb_lock_port(port_dev);
5794			port_event(hub, i);
5795			usb_unlock_port(port_dev);
5796			pm_runtime_put_sync(&port_dev->dev);
5797		}
5798	}
5799
5800	/* deal with hub status changes */
5801	if (test_and_clear_bit(0, hub->event_bits) == 0)
5802		;	/* do nothing */
5803	else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
5804		dev_err(hub_dev, "get_hub_status failed\n");
5805	else {
5806		if (hubchange & HUB_CHANGE_LOCAL_POWER) {
5807			dev_dbg(hub_dev, "power change\n");
5808			clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
5809			if (hubstatus & HUB_STATUS_LOCAL_POWER)
5810				/* FIXME: Is this always true? */
5811				hub->limited_power = 1;
5812			else
5813				hub->limited_power = 0;
5814		}
5815		if (hubchange & HUB_CHANGE_OVERCURRENT) {
5816			u16 status = 0;
5817			u16 unused;
5818
5819			dev_dbg(hub_dev, "over-current change\n");
5820			clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
5821			msleep(500);	/* Cool down */
5822			hub_power_on(hub, true);
5823			hub_hub_status(hub, &status, &unused);
5824			if (status & HUB_STATUS_OVERCURRENT)
5825				dev_err(hub_dev, "over-current condition\n");
5826		}
5827	}
5828
5829out_autopm:
5830	/* Balance the usb_autopm_get_interface() above */
5831	usb_autopm_put_interface_no_suspend(intf);
5832out_hdev_lock:
5833	usb_unlock_device(hdev);
5834
5835	/* Balance the stuff in kick_hub_wq() and allow autosuspend */
5836	usb_autopm_put_interface(intf);
5837	kref_put(&hub->kref, hub_release);
5838
5839	kcov_remote_stop();
5840}
5841
5842static const struct usb_device_id hub_id_table[] = {
5843    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5844                   | USB_DEVICE_ID_MATCH_PRODUCT
5845                   | USB_DEVICE_ID_MATCH_INT_CLASS,
5846      .idVendor = USB_VENDOR_SMSC,
5847      .idProduct = USB_PRODUCT_USB5534B,
5848      .bInterfaceClass = USB_CLASS_HUB,
5849      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5850    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5851                   | USB_DEVICE_ID_MATCH_PRODUCT,
5852      .idVendor = USB_VENDOR_CYPRESS,
5853      .idProduct = USB_PRODUCT_CY7C65632,
5854      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5855    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5856			| USB_DEVICE_ID_MATCH_INT_CLASS,
5857      .idVendor = USB_VENDOR_GENESYS_LOGIC,
5858      .bInterfaceClass = USB_CLASS_HUB,
5859      .driver_info = HUB_QUIRK_CHECK_PORT_AUTOSUSPEND},
5860    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5861			| USB_DEVICE_ID_MATCH_PRODUCT,
5862      .idVendor = USB_VENDOR_TEXAS_INSTRUMENTS,
5863      .idProduct = USB_PRODUCT_TUSB8041_USB2,
5864      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5865    { .match_flags = USB_DEVICE_ID_MATCH_VENDOR
5866			| USB_DEVICE_ID_MATCH_PRODUCT,
5867      .idVendor = USB_VENDOR_TEXAS_INSTRUMENTS,
5868      .idProduct = USB_PRODUCT_TUSB8041_USB3,
5869      .driver_info = HUB_QUIRK_DISABLE_AUTOSUSPEND},
5870    { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
5871      .bDeviceClass = USB_CLASS_HUB},
5872    { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
5873      .bInterfaceClass = USB_CLASS_HUB},
5874    { }						/* Terminating entry */
5875};
5876
5877MODULE_DEVICE_TABLE(usb, hub_id_table);
5878
5879static struct usb_driver hub_driver = {
5880	.name =		"hub",
5881	.probe =	hub_probe,
5882	.disconnect =	hub_disconnect,
5883	.suspend =	hub_suspend,
5884	.resume =	hub_resume,
5885	.reset_resume =	hub_reset_resume,
5886	.pre_reset =	hub_pre_reset,
5887	.post_reset =	hub_post_reset,
5888	.unlocked_ioctl = hub_ioctl,
5889	.id_table =	hub_id_table,
5890	.supports_autosuspend =	1,
5891};
5892
5893int usb_hub_init(void)
5894{
5895	if (usb_register(&hub_driver) < 0) {
5896		printk(KERN_ERR "%s: can't register hub driver\n",
5897			usbcore_name);
5898		return -1;
5899	}
5900
5901	/*
5902	 * The workqueue needs to be freezable to avoid interfering with
5903	 * USB-PERSIST port handover. Otherwise it might see that a full-speed
5904	 * device was gone before the EHCI controller had handed its port
5905	 * over to the companion full-speed controller.
5906	 */
5907	hub_wq = alloc_workqueue("usb_hub_wq", WQ_FREEZABLE, 0);
5908	if (hub_wq)
5909		return 0;
5910
5911	/* Fall through if kernel_thread failed */
5912	usb_deregister(&hub_driver);
5913	pr_err("%s: can't allocate workqueue for usb hub\n", usbcore_name);
5914
5915	return -1;
5916}
5917
5918void usb_hub_cleanup(void)
5919{
5920	destroy_workqueue(hub_wq);
5921
5922	/*
5923	 * Hub resources are freed for us by usb_deregister. It calls
5924	 * usb_driver_purge on every device which in turn calls that
5925	 * devices disconnect function if it is using this driver.
5926	 * The hub_disconnect function takes care of releasing the
5927	 * individual hub resources. -greg
5928	 */
5929	usb_deregister(&hub_driver);
5930} /* usb_hub_cleanup() */
5931
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5932/**
5933 * usb_reset_and_verify_device - perform a USB port reset to reinitialize a device
5934 * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
5935 *
5936 * WARNING - don't use this routine to reset a composite device
5937 * (one with multiple interfaces owned by separate drivers)!
5938 * Use usb_reset_device() instead.
5939 *
5940 * Do a port reset, reassign the device's address, and establish its
5941 * former operating configuration.  If the reset fails, or the device's
5942 * descriptors change from their values before the reset, or the original
5943 * configuration and altsettings cannot be restored, a flag will be set
5944 * telling hub_wq to pretend the device has been disconnected and then
5945 * re-connected.  All drivers will be unbound, and the device will be
5946 * re-enumerated and probed all over again.
5947 *
5948 * Return: 0 if the reset succeeded, -ENODEV if the device has been
5949 * flagged for logical disconnection, or some other negative error code
5950 * if the reset wasn't even attempted.
5951 *
5952 * Note:
5953 * The caller must own the device lock and the port lock, the latter is
5954 * taken by usb_reset_device().  For example, it's safe to use
5955 * usb_reset_device() from a driver probe() routine after downloading
5956 * new firmware.  For calls that might not occur during probe(), drivers
5957 * should lock the device using usb_lock_device_for_reset().
5958 *
5959 * Locking exception: This routine may also be called from within an
5960 * autoresume handler.  Such usage won't conflict with other tasks
5961 * holding the device lock because these tasks should always call
5962 * usb_autopm_resume_device(), thereby preventing any unwanted
5963 * autoresume.  The autoresume handler is expected to have already
5964 * acquired the port lock before calling this routine.
5965 */
5966static int usb_reset_and_verify_device(struct usb_device *udev)
5967{
5968	struct usb_device		*parent_hdev = udev->parent;
5969	struct usb_hub			*parent_hub;
5970	struct usb_hcd			*hcd = bus_to_hcd(udev->bus);
5971	struct usb_device_descriptor	descriptor = udev->descriptor;
5972	struct usb_host_bos		*bos;
5973	int				i, j, ret = 0;
5974	int				port1 = udev->portnum;
5975
5976	if (udev->state == USB_STATE_NOTATTACHED ||
5977			udev->state == USB_STATE_SUSPENDED) {
5978		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
5979				udev->state);
5980		return -EINVAL;
5981	}
5982
5983	if (!parent_hdev)
5984		return -EISDIR;
5985
5986	parent_hub = usb_hub_to_struct_hub(parent_hdev);
5987
5988	/* Disable USB2 hardware LPM.
5989	 * It will be re-enabled by the enumeration process.
5990	 */
5991	usb_disable_usb2_hardware_lpm(udev);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5992
5993	bos = udev->bos;
5994	udev->bos = NULL;
5995
5996	mutex_lock(hcd->address0_mutex);
5997
5998	for (i = 0; i < PORT_INIT_TRIES; ++i) {
5999		if (hub_port_stop_enumerate(parent_hub, port1, i)) {
6000			ret = -ENODEV;
6001			break;
6002		}
6003
6004		/* ep0 maxpacket size may change; let the HCD know about it.
6005		 * Other endpoints will be handled by re-enumeration. */
6006		usb_ep0_reinit(udev);
6007		ret = hub_port_init(parent_hub, udev, port1, i);
6008		if (ret >= 0 || ret == -ENOTCONN || ret == -ENODEV)
6009			break;
6010	}
6011	mutex_unlock(hcd->address0_mutex);
6012
6013	if (ret < 0)
6014		goto re_enumerate;
6015
6016	/* Device might have changed firmware (DFU or similar) */
6017	if (descriptors_changed(udev, &descriptor, bos)) {
6018		dev_info(&udev->dev, "device firmware changed\n");
6019		udev->descriptor = descriptor;	/* for disconnect() calls */
6020		goto re_enumerate;
6021	}
6022
6023	/* Restore the device's previous configuration */
6024	if (!udev->actconfig)
6025		goto done;
6026
6027	mutex_lock(hcd->bandwidth_mutex);
6028	ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
6029	if (ret < 0) {
6030		dev_warn(&udev->dev,
6031				"Busted HC?  Not enough HCD resources for "
6032				"old configuration.\n");
6033		mutex_unlock(hcd->bandwidth_mutex);
6034		goto re_enumerate;
6035	}
6036	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
6037			USB_REQ_SET_CONFIGURATION, 0,
6038			udev->actconfig->desc.bConfigurationValue, 0,
6039			NULL, 0, USB_CTRL_SET_TIMEOUT);
6040	if (ret < 0) {
6041		dev_err(&udev->dev,
6042			"can't restore configuration #%d (error=%d)\n",
6043			udev->actconfig->desc.bConfigurationValue, ret);
6044		mutex_unlock(hcd->bandwidth_mutex);
6045		goto re_enumerate;
6046	}
6047	mutex_unlock(hcd->bandwidth_mutex);
6048	usb_set_device_state(udev, USB_STATE_CONFIGURED);
6049
6050	/* Put interfaces back into the same altsettings as before.
6051	 * Don't bother to send the Set-Interface request for interfaces
6052	 * that were already in altsetting 0; besides being unnecessary,
6053	 * many devices can't handle it.  Instead just reset the host-side
6054	 * endpoint state.
6055	 */
6056	for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
6057		struct usb_host_config *config = udev->actconfig;
6058		struct usb_interface *intf = config->interface[i];
6059		struct usb_interface_descriptor *desc;
6060
6061		desc = &intf->cur_altsetting->desc;
6062		if (desc->bAlternateSetting == 0) {
6063			usb_disable_interface(udev, intf, true);
6064			usb_enable_interface(udev, intf, true);
6065			ret = 0;
6066		} else {
6067			/* Let the bandwidth allocation function know that this
6068			 * device has been reset, and it will have to use
6069			 * alternate setting 0 as the current alternate setting.
6070			 */
6071			intf->resetting_device = 1;
6072			ret = usb_set_interface(udev, desc->bInterfaceNumber,
6073					desc->bAlternateSetting);
6074			intf->resetting_device = 0;
6075		}
6076		if (ret < 0) {
6077			dev_err(&udev->dev, "failed to restore interface %d "
6078				"altsetting %d (error=%d)\n",
6079				desc->bInterfaceNumber,
6080				desc->bAlternateSetting,
6081				ret);
6082			goto re_enumerate;
6083		}
6084		/* Resetting also frees any allocated streams */
6085		for (j = 0; j < intf->cur_altsetting->desc.bNumEndpoints; j++)
6086			intf->cur_altsetting->endpoint[j].streams = 0;
6087	}
6088
6089done:
6090	/* Now that the alt settings are re-installed, enable LTM and LPM. */
6091	usb_enable_usb2_hardware_lpm(udev);
6092	usb_unlocked_enable_lpm(udev);
6093	usb_enable_ltm(udev);
6094	usb_release_bos_descriptor(udev);
6095	udev->bos = bos;
6096	return 0;
6097
6098re_enumerate:
6099	usb_release_bos_descriptor(udev);
6100	udev->bos = bos;
 
 
6101	hub_port_logical_disconnect(parent_hub, port1);
6102	return -ENODEV;
6103}
6104
6105/**
6106 * usb_reset_device - warn interface drivers and perform a USB port reset
6107 * @udev: device to reset (not in NOTATTACHED state)
6108 *
6109 * Warns all drivers bound to registered interfaces (using their pre_reset
6110 * method), performs the port reset, and then lets the drivers know that
6111 * the reset is over (using their post_reset method).
6112 *
6113 * Return: The same as for usb_reset_and_verify_device().
6114 * However, if a reset is already in progress (for instance, if a
6115 * driver doesn't have pre_reset() or post_reset() callbacks, and while
6116 * being unbound or re-bound during the ongoing reset its disconnect()
6117 * or probe() routine tries to perform a second, nested reset), the
6118 * routine returns -EINPROGRESS.
6119 *
6120 * Note:
6121 * The caller must own the device lock.  For example, it's safe to use
6122 * this from a driver probe() routine after downloading new firmware.
6123 * For calls that might not occur during probe(), drivers should lock
6124 * the device using usb_lock_device_for_reset().
6125 *
6126 * If an interface is currently being probed or disconnected, we assume
6127 * its driver knows how to handle resets.  For all other interfaces,
6128 * if the driver doesn't have pre_reset and post_reset methods then
6129 * we attempt to unbind it and rebind afterward.
6130 */
6131int usb_reset_device(struct usb_device *udev)
6132{
6133	int ret;
6134	int i;
6135	unsigned int noio_flag;
6136	struct usb_port *port_dev;
6137	struct usb_host_config *config = udev->actconfig;
6138	struct usb_hub *hub = usb_hub_to_struct_hub(udev->parent);
6139
6140	if (udev->state == USB_STATE_NOTATTACHED) {
 
6141		dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
6142				udev->state);
6143		return -EINVAL;
6144	}
6145
6146	if (!udev->parent) {
6147		/* this requires hcd-specific logic; see ohci_restart() */
6148		dev_dbg(&udev->dev, "%s for root hub!\n", __func__);
6149		return -EISDIR;
6150	}
6151
6152	if (udev->reset_in_progress)
6153		return -EINPROGRESS;
6154	udev->reset_in_progress = 1;
6155
6156	port_dev = hub->ports[udev->portnum - 1];
6157
6158	/*
6159	 * Don't allocate memory with GFP_KERNEL in current
6160	 * context to avoid possible deadlock if usb mass
6161	 * storage interface or usbnet interface(iSCSI case)
6162	 * is included in current configuration. The easist
6163	 * approach is to do it for every device reset,
6164	 * because the device 'memalloc_noio' flag may have
6165	 * not been set before reseting the usb device.
6166	 */
6167	noio_flag = memalloc_noio_save();
6168
6169	/* Prevent autosuspend during the reset */
6170	usb_autoresume_device(udev);
6171
6172	if (config) {
6173		for (i = 0; i < config->desc.bNumInterfaces; ++i) {
6174			struct usb_interface *cintf = config->interface[i];
6175			struct usb_driver *drv;
6176			int unbind = 0;
6177
6178			if (cintf->dev.driver) {
6179				drv = to_usb_driver(cintf->dev.driver);
6180				if (drv->pre_reset && drv->post_reset)
6181					unbind = (drv->pre_reset)(cintf);
6182				else if (cintf->condition ==
6183						USB_INTERFACE_BOUND)
6184					unbind = 1;
6185				if (unbind)
6186					usb_forced_unbind_intf(cintf);
6187			}
6188		}
6189	}
6190
6191	usb_lock_port(port_dev);
6192	ret = usb_reset_and_verify_device(udev);
6193	usb_unlock_port(port_dev);
6194
6195	if (config) {
6196		for (i = config->desc.bNumInterfaces - 1; i >= 0; --i) {
6197			struct usb_interface *cintf = config->interface[i];
6198			struct usb_driver *drv;
6199			int rebind = cintf->needs_binding;
6200
6201			if (!rebind && cintf->dev.driver) {
6202				drv = to_usb_driver(cintf->dev.driver);
6203				if (drv->post_reset)
6204					rebind = (drv->post_reset)(cintf);
6205				else if (cintf->condition ==
6206						USB_INTERFACE_BOUND)
6207					rebind = 1;
6208				if (rebind)
6209					cintf->needs_binding = 1;
6210			}
6211		}
6212
6213		/* If the reset failed, hub_wq will unbind drivers later */
6214		if (ret == 0)
6215			usb_unbind_and_rebind_marked_interfaces(udev);
6216	}
6217
6218	usb_autosuspend_device(udev);
6219	memalloc_noio_restore(noio_flag);
6220	udev->reset_in_progress = 0;
6221	return ret;
6222}
6223EXPORT_SYMBOL_GPL(usb_reset_device);
6224
6225
6226/**
6227 * usb_queue_reset_device - Reset a USB device from an atomic context
6228 * @iface: USB interface belonging to the device to reset
6229 *
6230 * This function can be used to reset a USB device from an atomic
6231 * context, where usb_reset_device() won't work (as it blocks).
6232 *
6233 * Doing a reset via this method is functionally equivalent to calling
6234 * usb_reset_device(), except for the fact that it is delayed to a
6235 * workqueue. This means that any drivers bound to other interfaces
6236 * might be unbound, as well as users from usbfs in user space.
6237 *
6238 * Corner cases:
6239 *
6240 * - Scheduling two resets at the same time from two different drivers
6241 *   attached to two different interfaces of the same device is
6242 *   possible; depending on how the driver attached to each interface
6243 *   handles ->pre_reset(), the second reset might happen or not.
6244 *
6245 * - If the reset is delayed so long that the interface is unbound from
6246 *   its driver, the reset will be skipped.
6247 *
6248 * - This function can be called during .probe().  It can also be called
6249 *   during .disconnect(), but doing so is pointless because the reset
6250 *   will not occur.  If you really want to reset the device during
6251 *   .disconnect(), call usb_reset_device() directly -- but watch out
6252 *   for nested unbinding issues!
6253 */
6254void usb_queue_reset_device(struct usb_interface *iface)
6255{
6256	if (schedule_work(&iface->reset_ws))
6257		usb_get_intf(iface);
6258}
6259EXPORT_SYMBOL_GPL(usb_queue_reset_device);
6260
6261/**
6262 * usb_hub_find_child - Get the pointer of child device
6263 * attached to the port which is specified by @port1.
6264 * @hdev: USB device belonging to the usb hub
6265 * @port1: port num to indicate which port the child device
6266 *	is attached to.
6267 *
6268 * USB drivers call this function to get hub's child device
6269 * pointer.
6270 *
6271 * Return: %NULL if input param is invalid and
6272 * child's usb_device pointer if non-NULL.
6273 */
6274struct usb_device *usb_hub_find_child(struct usb_device *hdev,
6275		int port1)
6276{
6277	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6278
6279	if (port1 < 1 || port1 > hdev->maxchild)
6280		return NULL;
6281	return hub->ports[port1 - 1]->child;
6282}
6283EXPORT_SYMBOL_GPL(usb_hub_find_child);
6284
6285void usb_hub_adjust_deviceremovable(struct usb_device *hdev,
6286		struct usb_hub_descriptor *desc)
6287{
6288	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6289	enum usb_port_connect_type connect_type;
6290	int i;
6291
6292	if (!hub)
6293		return;
6294
6295	if (!hub_is_superspeed(hdev)) {
6296		for (i = 1; i <= hdev->maxchild; i++) {
6297			struct usb_port *port_dev = hub->ports[i - 1];
6298
6299			connect_type = port_dev->connect_type;
6300			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6301				u8 mask = 1 << (i%8);
6302
6303				if (!(desc->u.hs.DeviceRemovable[i/8] & mask)) {
6304					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6305					desc->u.hs.DeviceRemovable[i/8]	|= mask;
6306				}
6307			}
6308		}
6309	} else {
6310		u16 port_removable = le16_to_cpu(desc->u.ss.DeviceRemovable);
6311
6312		for (i = 1; i <= hdev->maxchild; i++) {
6313			struct usb_port *port_dev = hub->ports[i - 1];
6314
6315			connect_type = port_dev->connect_type;
6316			if (connect_type == USB_PORT_CONNECT_TYPE_HARD_WIRED) {
6317				u16 mask = 1 << i;
6318
6319				if (!(port_removable & mask)) {
6320					dev_dbg(&port_dev->dev, "DeviceRemovable is changed to 1 according to platform information.\n");
6321					port_removable |= mask;
6322				}
6323			}
6324		}
6325
6326		desc->u.ss.DeviceRemovable = cpu_to_le16(port_removable);
6327	}
6328}
6329
6330#ifdef CONFIG_ACPI
6331/**
6332 * usb_get_hub_port_acpi_handle - Get the usb port's acpi handle
6333 * @hdev: USB device belonging to the usb hub
6334 * @port1: port num of the port
6335 *
6336 * Return: Port's acpi handle if successful, %NULL if params are
6337 * invalid.
6338 */
6339acpi_handle usb_get_hub_port_acpi_handle(struct usb_device *hdev,
6340	int port1)
6341{
6342	struct usb_hub *hub = usb_hub_to_struct_hub(hdev);
6343
6344	if (!hub)
6345		return NULL;
6346
6347	return ACPI_HANDLE(&hub->ports[port1 - 1]->dev);
6348}
6349#endif