Linux Audio

Check our new training course

Loading...
v5.9
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * (C) Copyright Linus Torvalds 1999
   4 * (C) Copyright Johannes Erdfelt 1999-2001
   5 * (C) Copyright Andreas Gal 1999
   6 * (C) Copyright Gregory P. Smith 1999
   7 * (C) Copyright Deti Fliegl 1999
   8 * (C) Copyright Randy Dunlap 2000
   9 * (C) Copyright David Brownell 2000-2002
  10 */
  11
  12#include <linux/bcd.h>
  13#include <linux/module.h>
  14#include <linux/version.h>
  15#include <linux/kernel.h>
  16#include <linux/sched/task_stack.h>
  17#include <linux/slab.h>
  18#include <linux/completion.h>
  19#include <linux/utsname.h>
  20#include <linux/mm.h>
  21#include <asm/io.h>
  22#include <linux/device.h>
  23#include <linux/dma-mapping.h>
  24#include <linux/mutex.h>
  25#include <asm/irq.h>
  26#include <asm/byteorder.h>
  27#include <asm/unaligned.h>
  28#include <linux/platform_device.h>
  29#include <linux/workqueue.h>
  30#include <linux/pm_runtime.h>
  31#include <linux/types.h>
  32#include <linux/genalloc.h>
  33#include <linux/io.h>
  34#include <linux/kcov.h>
  35
  36#include <linux/phy/phy.h>
  37#include <linux/usb.h>
  38#include <linux/usb/hcd.h>
  39#include <linux/usb/otg.h>
  40
  41#include "usb.h"
  42#include "phy.h"
  43
  44
  45/*-------------------------------------------------------------------------*/
  46
  47/*
  48 * USB Host Controller Driver framework
  49 *
  50 * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
  51 * HCD-specific behaviors/bugs.
  52 *
  53 * This does error checks, tracks devices and urbs, and delegates to a
  54 * "hc_driver" only for code (and data) that really needs to know about
  55 * hardware differences.  That includes root hub registers, i/o queues,
  56 * and so on ... but as little else as possible.
  57 *
  58 * Shared code includes most of the "root hub" code (these are emulated,
  59 * though each HC's hardware works differently) and PCI glue, plus request
  60 * tracking overhead.  The HCD code should only block on spinlocks or on
  61 * hardware handshaking; blocking on software events (such as other kernel
  62 * threads releasing resources, or completing actions) is all generic.
  63 *
  64 * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
  65 * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
  66 * only by the hub driver ... and that neither should be seen or used by
  67 * usb client device drivers.
  68 *
  69 * Contributors of ideas or unattributed patches include: David Brownell,
  70 * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
  71 *
  72 * HISTORY:
  73 * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
  74 *		associated cleanup.  "usb_hcd" still != "usb_bus".
  75 * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
  76 */
  77
  78/*-------------------------------------------------------------------------*/
  79
  80/* Keep track of which host controller drivers are loaded */
  81unsigned long usb_hcds_loaded;
  82EXPORT_SYMBOL_GPL(usb_hcds_loaded);
  83
  84/* host controllers we manage */
  85DEFINE_IDR (usb_bus_idr);
  86EXPORT_SYMBOL_GPL (usb_bus_idr);
  87
  88/* used when allocating bus numbers */
  89#define USB_MAXBUS		64
  90
  91/* used when updating list of hcds */
  92DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
  93EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
  94
  95/* used for controlling access to virtual root hubs */
  96static DEFINE_SPINLOCK(hcd_root_hub_lock);
  97
  98/* used when updating an endpoint's URB list */
  99static DEFINE_SPINLOCK(hcd_urb_list_lock);
 100
 101/* used to protect against unlinking URBs after the device is gone */
 102static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
 103
 104/* wait queue for synchronous unlinks */
 105DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
 106
 107/*-------------------------------------------------------------------------*/
 108
 109/*
 110 * Sharable chunks of root hub code.
 111 */
 112
 113/*-------------------------------------------------------------------------*/
 114#define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
 115#define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
 116
 117/* usb 3.1 root hub device descriptor */
 118static const u8 usb31_rh_dev_descriptor[18] = {
 119	0x12,       /*  __u8  bLength; */
 120	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 121	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
 122
 123	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
 124	0x00,	    /*  __u8  bDeviceSubClass; */
 125	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
 126	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
 127
 128	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 129	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
 130	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 131
 132	0x03,       /*  __u8  iManufacturer; */
 133	0x02,       /*  __u8  iProduct; */
 134	0x01,       /*  __u8  iSerialNumber; */
 135	0x01        /*  __u8  bNumConfigurations; */
 136};
 137
 138/* usb 3.0 root hub device descriptor */
 139static const u8 usb3_rh_dev_descriptor[18] = {
 140	0x12,       /*  __u8  bLength; */
 141	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 142	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
 143
 144	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
 145	0x00,	    /*  __u8  bDeviceSubClass; */
 146	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
 147	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
 148
 149	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 150	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
 151	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 152
 153	0x03,       /*  __u8  iManufacturer; */
 154	0x02,       /*  __u8  iProduct; */
 155	0x01,       /*  __u8  iSerialNumber; */
 156	0x01        /*  __u8  bNumConfigurations; */
 157};
 158
 159/* usb 2.5 (wireless USB 1.0) root hub device descriptor */
 160static const u8 usb25_rh_dev_descriptor[18] = {
 161	0x12,       /*  __u8  bLength; */
 162	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 163	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
 164
 165	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
 166	0x00,	    /*  __u8  bDeviceSubClass; */
 167	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
 168	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
 169
 170	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 171	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
 172	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 173
 174	0x03,       /*  __u8  iManufacturer; */
 175	0x02,       /*  __u8  iProduct; */
 176	0x01,       /*  __u8  iSerialNumber; */
 177	0x01        /*  __u8  bNumConfigurations; */
 178};
 179
 180/* usb 2.0 root hub device descriptor */
 181static const u8 usb2_rh_dev_descriptor[18] = {
 182	0x12,       /*  __u8  bLength; */
 183	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 184	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
 185
 186	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
 187	0x00,	    /*  __u8  bDeviceSubClass; */
 188	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
 189	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 190
 191	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 192	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
 193	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 194
 195	0x03,       /*  __u8  iManufacturer; */
 196	0x02,       /*  __u8  iProduct; */
 197	0x01,       /*  __u8  iSerialNumber; */
 198	0x01        /*  __u8  bNumConfigurations; */
 199};
 200
 201/* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
 202
 203/* usb 1.1 root hub device descriptor */
 204static const u8 usb11_rh_dev_descriptor[18] = {
 205	0x12,       /*  __u8  bLength; */
 206	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 207	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
 208
 209	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
 210	0x00,	    /*  __u8  bDeviceSubClass; */
 211	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
 212	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 213
 214	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 215	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
 216	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 217
 218	0x03,       /*  __u8  iManufacturer; */
 219	0x02,       /*  __u8  iProduct; */
 220	0x01,       /*  __u8  iSerialNumber; */
 221	0x01        /*  __u8  bNumConfigurations; */
 222};
 223
 224
 225/*-------------------------------------------------------------------------*/
 226
 227/* Configuration descriptors for our root hubs */
 228
 229static const u8 fs_rh_config_descriptor[] = {
 230
 231	/* one configuration */
 232	0x09,       /*  __u8  bLength; */
 233	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 234	0x19, 0x00, /*  __le16 wTotalLength; */
 235	0x01,       /*  __u8  bNumInterfaces; (1) */
 236	0x01,       /*  __u8  bConfigurationValue; */
 237	0x00,       /*  __u8  iConfiguration; */
 238	0xc0,       /*  __u8  bmAttributes;
 239				 Bit 7: must be set,
 240				     6: Self-powered,
 241				     5: Remote wakeup,
 242				     4..0: resvd */
 243	0x00,       /*  __u8  MaxPower; */
 244
 245	/* USB 1.1:
 246	 * USB 2.0, single TT organization (mandatory):
 247	 *	one interface, protocol 0
 248	 *
 249	 * USB 2.0, multiple TT organization (optional):
 250	 *	two interfaces, protocols 1 (like single TT)
 251	 *	and 2 (multiple TT mode) ... config is
 252	 *	sometimes settable
 253	 *	NOT IMPLEMENTED
 254	 */
 255
 256	/* one interface */
 257	0x09,       /*  __u8  if_bLength; */
 258	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
 259	0x00,       /*  __u8  if_bInterfaceNumber; */
 260	0x00,       /*  __u8  if_bAlternateSetting; */
 261	0x01,       /*  __u8  if_bNumEndpoints; */
 262	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 263	0x00,       /*  __u8  if_bInterfaceSubClass; */
 264	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 265	0x00,       /*  __u8  if_iInterface; */
 266
 267	/* one endpoint (status change endpoint) */
 268	0x07,       /*  __u8  ep_bLength; */
 269	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 270	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 271	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 272	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
 273	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
 274};
 275
 276static const u8 hs_rh_config_descriptor[] = {
 277
 278	/* one configuration */
 279	0x09,       /*  __u8  bLength; */
 280	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 281	0x19, 0x00, /*  __le16 wTotalLength; */
 282	0x01,       /*  __u8  bNumInterfaces; (1) */
 283	0x01,       /*  __u8  bConfigurationValue; */
 284	0x00,       /*  __u8  iConfiguration; */
 285	0xc0,       /*  __u8  bmAttributes;
 286				 Bit 7: must be set,
 287				     6: Self-powered,
 288				     5: Remote wakeup,
 289				     4..0: resvd */
 290	0x00,       /*  __u8  MaxPower; */
 291
 292	/* USB 1.1:
 293	 * USB 2.0, single TT organization (mandatory):
 294	 *	one interface, protocol 0
 295	 *
 296	 * USB 2.0, multiple TT organization (optional):
 297	 *	two interfaces, protocols 1 (like single TT)
 298	 *	and 2 (multiple TT mode) ... config is
 299	 *	sometimes settable
 300	 *	NOT IMPLEMENTED
 301	 */
 302
 303	/* one interface */
 304	0x09,       /*  __u8  if_bLength; */
 305	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
 306	0x00,       /*  __u8  if_bInterfaceNumber; */
 307	0x00,       /*  __u8  if_bAlternateSetting; */
 308	0x01,       /*  __u8  if_bNumEndpoints; */
 309	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 310	0x00,       /*  __u8  if_bInterfaceSubClass; */
 311	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 312	0x00,       /*  __u8  if_iInterface; */
 313
 314	/* one endpoint (status change endpoint) */
 315	0x07,       /*  __u8  ep_bLength; */
 316	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 317	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 318	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 319		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 320		     * see hub.c:hub_configure() for details. */
 321	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 322	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 323};
 324
 325static const u8 ss_rh_config_descriptor[] = {
 326	/* one configuration */
 327	0x09,       /*  __u8  bLength; */
 328	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 329	0x1f, 0x00, /*  __le16 wTotalLength; */
 330	0x01,       /*  __u8  bNumInterfaces; (1) */
 331	0x01,       /*  __u8  bConfigurationValue; */
 332	0x00,       /*  __u8  iConfiguration; */
 333	0xc0,       /*  __u8  bmAttributes;
 334				 Bit 7: must be set,
 335				     6: Self-powered,
 336				     5: Remote wakeup,
 337				     4..0: resvd */
 338	0x00,       /*  __u8  MaxPower; */
 339
 340	/* one interface */
 341	0x09,       /*  __u8  if_bLength; */
 342	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
 343	0x00,       /*  __u8  if_bInterfaceNumber; */
 344	0x00,       /*  __u8  if_bAlternateSetting; */
 345	0x01,       /*  __u8  if_bNumEndpoints; */
 346	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 347	0x00,       /*  __u8  if_bInterfaceSubClass; */
 348	0x00,       /*  __u8  if_bInterfaceProtocol; */
 349	0x00,       /*  __u8  if_iInterface; */
 350
 351	/* one endpoint (status change endpoint) */
 352	0x07,       /*  __u8  ep_bLength; */
 353	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 354	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 355	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 356		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 357		     * see hub.c:hub_configure() for details. */
 358	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 359	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 360
 361	/* one SuperSpeed endpoint companion descriptor */
 362	0x06,        /* __u8 ss_bLength */
 363	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
 364		     /* Companion */
 365	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
 366	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
 367	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
 368};
 369
 370/* authorized_default behaviour:
 371 * -1 is authorized for all devices except wireless (old behaviour)
 372 * 0 is unauthorized for all devices
 373 * 1 is authorized for all devices
 374 * 2 is authorized for internal devices
 375 */
 376#define USB_AUTHORIZE_WIRED	-1
 377#define USB_AUTHORIZE_NONE	0
 378#define USB_AUTHORIZE_ALL	1
 379#define USB_AUTHORIZE_INTERNAL	2
 380
 381static int authorized_default = USB_AUTHORIZE_WIRED;
 382module_param(authorized_default, int, S_IRUGO|S_IWUSR);
 383MODULE_PARM_DESC(authorized_default,
 384		"Default USB device authorization: 0 is not authorized, 1 is "
 385		"authorized, 2 is authorized for internal devices, -1 is "
 386		"authorized except for wireless USB (default, old behaviour)");
 387/*-------------------------------------------------------------------------*/
 388
 389/**
 390 * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
 391 * @s: Null-terminated ASCII (actually ISO-8859-1) string
 392 * @buf: Buffer for USB string descriptor (header + UTF-16LE)
 393 * @len: Length (in bytes; may be odd) of descriptor buffer.
 394 *
 395 * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
 396 * whichever is less.
 397 *
 398 * Note:
 399 * USB String descriptors can contain at most 126 characters; input
 400 * strings longer than that are truncated.
 401 */
 402static unsigned
 403ascii2desc(char const *s, u8 *buf, unsigned len)
 404{
 405	unsigned n, t = 2 + 2*strlen(s);
 406
 407	if (t > 254)
 408		t = 254;	/* Longest possible UTF string descriptor */
 409	if (len > t)
 410		len = t;
 411
 412	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
 413
 414	n = len;
 415	while (n--) {
 416		*buf++ = t;
 417		if (!n--)
 418			break;
 419		*buf++ = t >> 8;
 420		t = (unsigned char)*s++;
 421	}
 422	return len;
 423}
 424
 425/**
 426 * rh_string() - provides string descriptors for root hub
 427 * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
 428 * @hcd: the host controller for this root hub
 429 * @data: buffer for output packet
 430 * @len: length of the provided buffer
 431 *
 432 * Produces either a manufacturer, product or serial number string for the
 433 * virtual root hub device.
 434 *
 435 * Return: The number of bytes filled in: the length of the descriptor or
 436 * of the provided buffer, whichever is less.
 437 */
 438static unsigned
 439rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
 440{
 441	char buf[100];
 442	char const *s;
 443	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
 444
 445	/* language ids */
 446	switch (id) {
 447	case 0:
 448		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
 449		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
 450		if (len > 4)
 451			len = 4;
 452		memcpy(data, langids, len);
 453		return len;
 454	case 1:
 455		/* Serial number */
 456		s = hcd->self.bus_name;
 457		break;
 458	case 2:
 459		/* Product name */
 460		s = hcd->product_desc;
 461		break;
 462	case 3:
 463		/* Manufacturer */
 464		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
 465			init_utsname()->release, hcd->driver->description);
 466		s = buf;
 467		break;
 468	default:
 469		/* Can't happen; caller guarantees it */
 470		return 0;
 471	}
 472
 473	return ascii2desc(s, data, len);
 474}
 475
 476
 477/* Root hub control transfers execute synchronously */
 478static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
 479{
 480	struct usb_ctrlrequest *cmd;
 481	u16		typeReq, wValue, wIndex, wLength;
 482	u8		*ubuf = urb->transfer_buffer;
 483	unsigned	len = 0;
 484	int		status;
 485	u8		patch_wakeup = 0;
 486	u8		patch_protocol = 0;
 487	u16		tbuf_size;
 488	u8		*tbuf = NULL;
 489	const u8	*bufp;
 490
 491	might_sleep();
 492
 493	spin_lock_irq(&hcd_root_hub_lock);
 494	status = usb_hcd_link_urb_to_ep(hcd, urb);
 495	spin_unlock_irq(&hcd_root_hub_lock);
 496	if (status)
 497		return status;
 498	urb->hcpriv = hcd;	/* Indicate it's queued */
 499
 500	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
 501	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
 502	wValue   = le16_to_cpu (cmd->wValue);
 503	wIndex   = le16_to_cpu (cmd->wIndex);
 504	wLength  = le16_to_cpu (cmd->wLength);
 505
 506	if (wLength > urb->transfer_buffer_length)
 507		goto error;
 508
 509	/*
 510	 * tbuf should be at least as big as the
 511	 * USB hub descriptor.
 512	 */
 513	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
 514	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
 515	if (!tbuf) {
 516		status = -ENOMEM;
 517		goto err_alloc;
 518	}
 519
 520	bufp = tbuf;
 521
 522
 523	urb->actual_length = 0;
 524	switch (typeReq) {
 525
 526	/* DEVICE REQUESTS */
 527
 528	/* The root hub's remote wakeup enable bit is implemented using
 529	 * driver model wakeup flags.  If this system supports wakeup
 530	 * through USB, userspace may change the default "allow wakeup"
 531	 * policy through sysfs or these calls.
 532	 *
 533	 * Most root hubs support wakeup from downstream devices, for
 534	 * runtime power management (disabling USB clocks and reducing
 535	 * VBUS power usage).  However, not all of them do so; silicon,
 536	 * board, and BIOS bugs here are not uncommon, so these can't
 537	 * be treated quite like external hubs.
 538	 *
 539	 * Likewise, not all root hubs will pass wakeup events upstream,
 540	 * to wake up the whole system.  So don't assume root hub and
 541	 * controller capabilities are identical.
 542	 */
 543
 544	case DeviceRequest | USB_REQ_GET_STATUS:
 545		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
 546					<< USB_DEVICE_REMOTE_WAKEUP)
 547				| (1 << USB_DEVICE_SELF_POWERED);
 548		tbuf[1] = 0;
 549		len = 2;
 550		break;
 551	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
 552		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
 553			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
 554		else
 555			goto error;
 556		break;
 557	case DeviceOutRequest | USB_REQ_SET_FEATURE:
 558		if (device_can_wakeup(&hcd->self.root_hub->dev)
 559				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
 560			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
 561		else
 562			goto error;
 563		break;
 564	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
 565		tbuf[0] = 1;
 566		len = 1;
 567		fallthrough;
 568	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
 569		break;
 570	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 571		switch (wValue & 0xff00) {
 572		case USB_DT_DEVICE << 8:
 573			switch (hcd->speed) {
 574			case HCD_USB32:
 575			case HCD_USB31:
 576				bufp = usb31_rh_dev_descriptor;
 577				break;
 578			case HCD_USB3:
 579				bufp = usb3_rh_dev_descriptor;
 580				break;
 581			case HCD_USB25:
 582				bufp = usb25_rh_dev_descriptor;
 583				break;
 584			case HCD_USB2:
 585				bufp = usb2_rh_dev_descriptor;
 586				break;
 587			case HCD_USB11:
 588				bufp = usb11_rh_dev_descriptor;
 589				break;
 590			default:
 591				goto error;
 592			}
 593			len = 18;
 594			if (hcd->has_tt)
 595				patch_protocol = 1;
 596			break;
 597		case USB_DT_CONFIG << 8:
 598			switch (hcd->speed) {
 599			case HCD_USB32:
 600			case HCD_USB31:
 601			case HCD_USB3:
 602				bufp = ss_rh_config_descriptor;
 603				len = sizeof ss_rh_config_descriptor;
 604				break;
 605			case HCD_USB25:
 606			case HCD_USB2:
 607				bufp = hs_rh_config_descriptor;
 608				len = sizeof hs_rh_config_descriptor;
 609				break;
 610			case HCD_USB11:
 611				bufp = fs_rh_config_descriptor;
 612				len = sizeof fs_rh_config_descriptor;
 613				break;
 614			default:
 615				goto error;
 616			}
 617			if (device_can_wakeup(&hcd->self.root_hub->dev))
 618				patch_wakeup = 1;
 619			break;
 620		case USB_DT_STRING << 8:
 621			if ((wValue & 0xff) < 4)
 622				urb->actual_length = rh_string(wValue & 0xff,
 623						hcd, ubuf, wLength);
 624			else /* unsupported IDs --> "protocol stall" */
 625				goto error;
 626			break;
 627		case USB_DT_BOS << 8:
 628			goto nongeneric;
 629		default:
 630			goto error;
 631		}
 632		break;
 633	case DeviceRequest | USB_REQ_GET_INTERFACE:
 634		tbuf[0] = 0;
 635		len = 1;
 636		fallthrough;
 637	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
 638		break;
 639	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
 640		/* wValue == urb->dev->devaddr */
 641		dev_dbg (hcd->self.controller, "root hub device address %d\n",
 642			wValue);
 643		break;
 644
 645	/* INTERFACE REQUESTS (no defined feature/status flags) */
 646
 647	/* ENDPOINT REQUESTS */
 648
 649	case EndpointRequest | USB_REQ_GET_STATUS:
 650		/* ENDPOINT_HALT flag */
 651		tbuf[0] = 0;
 652		tbuf[1] = 0;
 653		len = 2;
 654		fallthrough;
 655	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
 656	case EndpointOutRequest | USB_REQ_SET_FEATURE:
 657		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
 658		break;
 659
 660	/* CLASS REQUESTS (and errors) */
 661
 662	default:
 663nongeneric:
 664		/* non-generic request */
 665		switch (typeReq) {
 666		case GetHubStatus:
 667			len = 4;
 668			break;
 669		case GetPortStatus:
 670			if (wValue == HUB_PORT_STATUS)
 671				len = 4;
 672			else
 673				/* other port status types return 8 bytes */
 674				len = 8;
 675			break;
 676		case GetHubDescriptor:
 677			len = sizeof (struct usb_hub_descriptor);
 678			break;
 679		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 680			/* len is returned by hub_control */
 681			break;
 682		}
 683		status = hcd->driver->hub_control (hcd,
 684			typeReq, wValue, wIndex,
 685			tbuf, wLength);
 686
 687		if (typeReq == GetHubDescriptor)
 688			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
 689				(struct usb_hub_descriptor *)tbuf);
 690		break;
 691error:
 692		/* "protocol stall" on error */
 693		status = -EPIPE;
 694	}
 695
 696	if (status < 0) {
 697		len = 0;
 698		if (status != -EPIPE) {
 699			dev_dbg (hcd->self.controller,
 700				"CTRL: TypeReq=0x%x val=0x%x "
 701				"idx=0x%x len=%d ==> %d\n",
 702				typeReq, wValue, wIndex,
 703				wLength, status);
 704		}
 705	} else if (status > 0) {
 706		/* hub_control may return the length of data copied. */
 707		len = status;
 708		status = 0;
 709	}
 710	if (len) {
 711		if (urb->transfer_buffer_length < len)
 712			len = urb->transfer_buffer_length;
 713		urb->actual_length = len;
 714		/* always USB_DIR_IN, toward host */
 715		memcpy (ubuf, bufp, len);
 716
 717		/* report whether RH hardware supports remote wakeup */
 718		if (patch_wakeup &&
 719				len > offsetof (struct usb_config_descriptor,
 720						bmAttributes))
 721			((struct usb_config_descriptor *)ubuf)->bmAttributes
 722				|= USB_CONFIG_ATT_WAKEUP;
 723
 724		/* report whether RH hardware has an integrated TT */
 725		if (patch_protocol &&
 726				len > offsetof(struct usb_device_descriptor,
 727						bDeviceProtocol))
 728			((struct usb_device_descriptor *) ubuf)->
 729				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
 730	}
 731
 732	kfree(tbuf);
 733 err_alloc:
 734
 735	/* any errors get returned through the urb completion */
 736	spin_lock_irq(&hcd_root_hub_lock);
 737	usb_hcd_unlink_urb_from_ep(hcd, urb);
 738	usb_hcd_giveback_urb(hcd, urb, status);
 739	spin_unlock_irq(&hcd_root_hub_lock);
 740	return 0;
 741}
 742
 743/*-------------------------------------------------------------------------*/
 744
 745/*
 746 * Root Hub interrupt transfers are polled using a timer if the
 747 * driver requests it; otherwise the driver is responsible for
 748 * calling usb_hcd_poll_rh_status() when an event occurs.
 749 *
 750 * Completions are called in_interrupt(), but they may or may not
 751 * be in_irq().
 752 */
 753void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
 754{
 755	struct urb	*urb;
 756	int		length;
 757	unsigned long	flags;
 758	char		buffer[6];	/* Any root hubs with > 31 ports? */
 759
 760	if (unlikely(!hcd->rh_pollable))
 761		return;
 762	if (!hcd->uses_new_polling && !hcd->status_urb)
 763		return;
 764
 765	length = hcd->driver->hub_status_data(hcd, buffer);
 766	if (length > 0) {
 767
 768		/* try to complete the status urb */
 769		spin_lock_irqsave(&hcd_root_hub_lock, flags);
 770		urb = hcd->status_urb;
 771		if (urb) {
 772			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 773			hcd->status_urb = NULL;
 774			urb->actual_length = length;
 775			memcpy(urb->transfer_buffer, buffer, length);
 776
 777			usb_hcd_unlink_urb_from_ep(hcd, urb);
 778			usb_hcd_giveback_urb(hcd, urb, 0);
 779		} else {
 780			length = 0;
 781			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 782		}
 783		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 784	}
 785
 786	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
 787	 * exceed that limit if HZ is 100. The math is more clunky than
 788	 * maybe expected, this is to make sure that all timers for USB devices
 789	 * fire at the same time to give the CPU a break in between */
 790	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
 791			(length == 0 && hcd->status_urb != NULL))
 792		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 793}
 794EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
 795
 796/* timer callback */
 797static void rh_timer_func (struct timer_list *t)
 798{
 799	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
 800
 801	usb_hcd_poll_rh_status(_hcd);
 802}
 803
 804/*-------------------------------------------------------------------------*/
 805
 806static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
 807{
 808	int		retval;
 809	unsigned long	flags;
 810	unsigned	len = 1 + (urb->dev->maxchild / 8);
 811
 812	spin_lock_irqsave (&hcd_root_hub_lock, flags);
 813	if (hcd->status_urb || urb->transfer_buffer_length < len) {
 814		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
 815		retval = -EINVAL;
 816		goto done;
 817	}
 818
 819	retval = usb_hcd_link_urb_to_ep(hcd, urb);
 820	if (retval)
 821		goto done;
 822
 823	hcd->status_urb = urb;
 824	urb->hcpriv = hcd;	/* indicate it's queued */
 825	if (!hcd->uses_new_polling)
 826		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 827
 828	/* If a status change has already occurred, report it ASAP */
 829	else if (HCD_POLL_PENDING(hcd))
 830		mod_timer(&hcd->rh_timer, jiffies);
 831	retval = 0;
 832 done:
 833	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
 834	return retval;
 835}
 836
 837static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
 838{
 839	if (usb_endpoint_xfer_int(&urb->ep->desc))
 840		return rh_queue_status (hcd, urb);
 841	if (usb_endpoint_xfer_control(&urb->ep->desc))
 842		return rh_call_control (hcd, urb);
 843	return -EINVAL;
 844}
 845
 846/*-------------------------------------------------------------------------*/
 847
 848/* Unlinks of root-hub control URBs are legal, but they don't do anything
 849 * since these URBs always execute synchronously.
 850 */
 851static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 852{
 853	unsigned long	flags;
 854	int		rc;
 855
 856	spin_lock_irqsave(&hcd_root_hub_lock, flags);
 857	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
 858	if (rc)
 859		goto done;
 860
 861	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
 862		;	/* Do nothing */
 863
 864	} else {				/* Status URB */
 865		if (!hcd->uses_new_polling)
 866			del_timer (&hcd->rh_timer);
 867		if (urb == hcd->status_urb) {
 868			hcd->status_urb = NULL;
 869			usb_hcd_unlink_urb_from_ep(hcd, urb);
 870			usb_hcd_giveback_urb(hcd, urb, status);
 871		}
 872	}
 873 done:
 874	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 875	return rc;
 876}
 877
 878
 879/*-------------------------------------------------------------------------*/
 880
 881/**
 882 * usb_bus_init - shared initialization code
 883 * @bus: the bus structure being initialized
 884 *
 885 * This code is used to initialize a usb_bus structure, memory for which is
 886 * separately managed.
 887 */
 888static void usb_bus_init (struct usb_bus *bus)
 889{
 890	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
 891
 892	bus->devnum_next = 1;
 893
 894	bus->root_hub = NULL;
 895	bus->busnum = -1;
 896	bus->bandwidth_allocated = 0;
 897	bus->bandwidth_int_reqs  = 0;
 898	bus->bandwidth_isoc_reqs = 0;
 899	mutex_init(&bus->devnum_next_mutex);
 900}
 901
 902/*-------------------------------------------------------------------------*/
 903
 904/**
 905 * usb_register_bus - registers the USB host controller with the usb core
 906 * @bus: pointer to the bus to register
 907 * Context: !in_interrupt()
 908 *
 909 * Assigns a bus number, and links the controller into usbcore data
 910 * structures so that it can be seen by scanning the bus list.
 911 *
 912 * Return: 0 if successful. A negative error code otherwise.
 913 */
 914static int usb_register_bus(struct usb_bus *bus)
 915{
 916	int result = -E2BIG;
 917	int busnum;
 918
 919	mutex_lock(&usb_bus_idr_lock);
 920	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
 921	if (busnum < 0) {
 922		pr_err("%s: failed to get bus number\n", usbcore_name);
 923		goto error_find_busnum;
 924	}
 925	bus->busnum = busnum;
 926	mutex_unlock(&usb_bus_idr_lock);
 927
 928	usb_notify_add_bus(bus);
 929
 930	dev_info (bus->controller, "new USB bus registered, assigned bus "
 931		  "number %d\n", bus->busnum);
 932	return 0;
 933
 934error_find_busnum:
 935	mutex_unlock(&usb_bus_idr_lock);
 936	return result;
 937}
 938
 939/**
 940 * usb_deregister_bus - deregisters the USB host controller
 941 * @bus: pointer to the bus to deregister
 942 * Context: !in_interrupt()
 943 *
 944 * Recycles the bus number, and unlinks the controller from usbcore data
 945 * structures so that it won't be seen by scanning the bus list.
 946 */
 947static void usb_deregister_bus (struct usb_bus *bus)
 948{
 949	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
 950
 951	/*
 952	 * NOTE: make sure that all the devices are removed by the
 953	 * controller code, as well as having it call this when cleaning
 954	 * itself up
 955	 */
 956	mutex_lock(&usb_bus_idr_lock);
 957	idr_remove(&usb_bus_idr, bus->busnum);
 958	mutex_unlock(&usb_bus_idr_lock);
 959
 960	usb_notify_remove_bus(bus);
 961}
 962
 963/**
 964 * register_root_hub - called by usb_add_hcd() to register a root hub
 965 * @hcd: host controller for this root hub
 966 *
 967 * This function registers the root hub with the USB subsystem.  It sets up
 968 * the device properly in the device tree and then calls usb_new_device()
 969 * to register the usb device.  It also assigns the root hub's USB address
 970 * (always 1).
 971 *
 972 * Return: 0 if successful. A negative error code otherwise.
 973 */
 974static int register_root_hub(struct usb_hcd *hcd)
 975{
 976	struct device *parent_dev = hcd->self.controller;
 977	struct usb_device *usb_dev = hcd->self.root_hub;
 978	const int devnum = 1;
 979	int retval;
 980
 981	usb_dev->devnum = devnum;
 982	usb_dev->bus->devnum_next = devnum + 1;
 983	set_bit (devnum, usb_dev->bus->devmap.devicemap);
 984	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
 985
 986	mutex_lock(&usb_bus_idr_lock);
 987
 988	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
 989	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
 990	if (retval != sizeof usb_dev->descriptor) {
 991		mutex_unlock(&usb_bus_idr_lock);
 992		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
 993				dev_name(&usb_dev->dev), retval);
 994		return (retval < 0) ? retval : -EMSGSIZE;
 995	}
 996
 997	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
 998		retval = usb_get_bos_descriptor(usb_dev);
 999		if (!retval) {
1000			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1001		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1002			mutex_unlock(&usb_bus_idr_lock);
1003			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1004					dev_name(&usb_dev->dev), retval);
1005			return retval;
1006		}
1007	}
1008
1009	retval = usb_new_device (usb_dev);
1010	if (retval) {
1011		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1012				dev_name(&usb_dev->dev), retval);
1013	} else {
1014		spin_lock_irq (&hcd_root_hub_lock);
1015		hcd->rh_registered = 1;
1016		spin_unlock_irq (&hcd_root_hub_lock);
1017
1018		/* Did the HC die before the root hub was registered? */
1019		if (HCD_DEAD(hcd))
1020			usb_hc_died (hcd);	/* This time clean up */
1021	}
1022	mutex_unlock(&usb_bus_idr_lock);
1023
1024	return retval;
1025}
1026
1027/*
1028 * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1029 * @bus: the bus which the root hub belongs to
1030 * @portnum: the port which is being resumed
1031 *
1032 * HCDs should call this function when they know that a resume signal is
1033 * being sent to a root-hub port.  The root hub will be prevented from
1034 * going into autosuspend until usb_hcd_end_port_resume() is called.
1035 *
1036 * The bus's private lock must be held by the caller.
1037 */
1038void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1039{
1040	unsigned bit = 1 << portnum;
1041
1042	if (!(bus->resuming_ports & bit)) {
1043		bus->resuming_ports |= bit;
1044		pm_runtime_get_noresume(&bus->root_hub->dev);
1045	}
1046}
1047EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1048
1049/*
1050 * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1051 * @bus: the bus which the root hub belongs to
1052 * @portnum: the port which is being resumed
1053 *
1054 * HCDs should call this function when they know that a resume signal has
1055 * stopped being sent to a root-hub port.  The root hub will be allowed to
1056 * autosuspend again.
1057 *
1058 * The bus's private lock must be held by the caller.
1059 */
1060void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1061{
1062	unsigned bit = 1 << portnum;
1063
1064	if (bus->resuming_ports & bit) {
1065		bus->resuming_ports &= ~bit;
1066		pm_runtime_put_noidle(&bus->root_hub->dev);
1067	}
1068}
1069EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1070
1071/*-------------------------------------------------------------------------*/
1072
1073/**
1074 * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1075 * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1076 * @is_input: true iff the transaction sends data to the host
1077 * @isoc: true for isochronous transactions, false for interrupt ones
1078 * @bytecount: how many bytes in the transaction.
1079 *
1080 * Return: Approximate bus time in nanoseconds for a periodic transaction.
1081 *
1082 * Note:
1083 * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1084 * scheduled in software, this function is only used for such scheduling.
1085 */
1086long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1087{
1088	unsigned long	tmp;
1089
1090	switch (speed) {
1091	case USB_SPEED_LOW: 	/* INTR only */
1092		if (is_input) {
1093			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1094			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1095		} else {
1096			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1097			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1098		}
1099	case USB_SPEED_FULL:	/* ISOC or INTR */
1100		if (isoc) {
1101			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1102			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1103		} else {
1104			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1105			return 9107L + BW_HOST_DELAY + tmp;
1106		}
1107	case USB_SPEED_HIGH:	/* ISOC or INTR */
1108		/* FIXME adjust for input vs output */
1109		if (isoc)
1110			tmp = HS_NSECS_ISO (bytecount);
1111		else
1112			tmp = HS_NSECS (bytecount);
1113		return tmp;
1114	default:
1115		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1116		return -1;
1117	}
1118}
1119EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1120
1121
1122/*-------------------------------------------------------------------------*/
1123
1124/*
1125 * Generic HC operations.
1126 */
1127
1128/*-------------------------------------------------------------------------*/
1129
1130/**
1131 * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1132 * @hcd: host controller to which @urb was submitted
1133 * @urb: URB being submitted
1134 *
1135 * Host controller drivers should call this routine in their enqueue()
1136 * method.  The HCD's private spinlock must be held and interrupts must
1137 * be disabled.  The actions carried out here are required for URB
1138 * submission, as well as for endpoint shutdown and for usb_kill_urb.
1139 *
1140 * Return: 0 for no error, otherwise a negative error code (in which case
1141 * the enqueue() method must fail).  If no error occurs but enqueue() fails
1142 * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1143 * the private spinlock and returning.
1144 */
1145int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1146{
1147	int		rc = 0;
1148
1149	spin_lock(&hcd_urb_list_lock);
1150
1151	/* Check that the URB isn't being killed */
1152	if (unlikely(atomic_read(&urb->reject))) {
1153		rc = -EPERM;
1154		goto done;
1155	}
1156
1157	if (unlikely(!urb->ep->enabled)) {
1158		rc = -ENOENT;
1159		goto done;
1160	}
1161
1162	if (unlikely(!urb->dev->can_submit)) {
1163		rc = -EHOSTUNREACH;
1164		goto done;
1165	}
1166
1167	/*
1168	 * Check the host controller's state and add the URB to the
1169	 * endpoint's queue.
1170	 */
1171	if (HCD_RH_RUNNING(hcd)) {
1172		urb->unlinked = 0;
1173		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1174	} else {
1175		rc = -ESHUTDOWN;
1176		goto done;
1177	}
1178 done:
1179	spin_unlock(&hcd_urb_list_lock);
1180	return rc;
1181}
1182EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1183
1184/**
1185 * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1186 * @hcd: host controller to which @urb was submitted
1187 * @urb: URB being checked for unlinkability
1188 * @status: error code to store in @urb if the unlink succeeds
1189 *
1190 * Host controller drivers should call this routine in their dequeue()
1191 * method.  The HCD's private spinlock must be held and interrupts must
1192 * be disabled.  The actions carried out here are required for making
1193 * sure than an unlink is valid.
1194 *
1195 * Return: 0 for no error, otherwise a negative error code (in which case
1196 * the dequeue() method must fail).  The possible error codes are:
1197 *
1198 *	-EIDRM: @urb was not submitted or has already completed.
1199 *		The completion function may not have been called yet.
1200 *
1201 *	-EBUSY: @urb has already been unlinked.
1202 */
1203int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1204		int status)
1205{
1206	struct list_head	*tmp;
1207
1208	/* insist the urb is still queued */
1209	list_for_each(tmp, &urb->ep->urb_list) {
1210		if (tmp == &urb->urb_list)
1211			break;
1212	}
1213	if (tmp != &urb->urb_list)
1214		return -EIDRM;
1215
1216	/* Any status except -EINPROGRESS means something already started to
1217	 * unlink this URB from the hardware.  So there's no more work to do.
1218	 */
1219	if (urb->unlinked)
1220		return -EBUSY;
1221	urb->unlinked = status;
1222	return 0;
1223}
1224EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1225
1226/**
1227 * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1228 * @hcd: host controller to which @urb was submitted
1229 * @urb: URB being unlinked
1230 *
1231 * Host controller drivers should call this routine before calling
1232 * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1233 * interrupts must be disabled.  The actions carried out here are required
1234 * for URB completion.
1235 */
1236void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1237{
1238	/* clear all state linking urb to this dev (and hcd) */
1239	spin_lock(&hcd_urb_list_lock);
1240	list_del_init(&urb->urb_list);
1241	spin_unlock(&hcd_urb_list_lock);
1242}
1243EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1244
1245/*
1246 * Some usb host controllers can only perform dma using a small SRAM area.
1247 * The usb core itself is however optimized for host controllers that can dma
1248 * using regular system memory - like pci devices doing bus mastering.
1249 *
1250 * To support host controllers with limited dma capabilities we provide dma
1251 * bounce buffers. This feature can be enabled by initializing
1252 * hcd->localmem_pool using usb_hcd_setup_local_mem().
1253 *
1254 * The initialized hcd->localmem_pool then tells the usb code to allocate all
1255 * data for dma using the genalloc API.
1256 *
1257 * So, to summarize...
1258 *
1259 * - We need "local" memory, canonical example being
1260 *   a small SRAM on a discrete controller being the
1261 *   only memory that the controller can read ...
1262 *   (a) "normal" kernel memory is no good, and
1263 *   (b) there's not enough to share
1264 *
1265 * - So we use that, even though the primary requirement
1266 *   is that the memory be "local" (hence addressable
1267 *   by that device), not "coherent".
1268 *
1269 */
1270
1271static int hcd_alloc_coherent(struct usb_bus *bus,
1272			      gfp_t mem_flags, dma_addr_t *dma_handle,
1273			      void **vaddr_handle, size_t size,
1274			      enum dma_data_direction dir)
1275{
1276	unsigned char *vaddr;
1277
1278	if (*vaddr_handle == NULL) {
1279		WARN_ON_ONCE(1);
1280		return -EFAULT;
1281	}
1282
1283	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1284				 mem_flags, dma_handle);
1285	if (!vaddr)
1286		return -ENOMEM;
1287
1288	/*
1289	 * Store the virtual address of the buffer at the end
1290	 * of the allocated dma buffer. The size of the buffer
1291	 * may be uneven so use unaligned functions instead
1292	 * of just rounding up. It makes sense to optimize for
1293	 * memory footprint over access speed since the amount
1294	 * of memory available for dma may be limited.
1295	 */
1296	put_unaligned((unsigned long)*vaddr_handle,
1297		      (unsigned long *)(vaddr + size));
1298
1299	if (dir == DMA_TO_DEVICE)
1300		memcpy(vaddr, *vaddr_handle, size);
1301
1302	*vaddr_handle = vaddr;
1303	return 0;
1304}
1305
1306static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1307			      void **vaddr_handle, size_t size,
1308			      enum dma_data_direction dir)
1309{
1310	unsigned char *vaddr = *vaddr_handle;
1311
1312	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1313
1314	if (dir == DMA_FROM_DEVICE)
1315		memcpy(vaddr, *vaddr_handle, size);
1316
1317	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1318
1319	*vaddr_handle = vaddr;
1320	*dma_handle = 0;
1321}
1322
1323void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1324{
1325	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1326	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1327		dma_unmap_single(hcd->self.sysdev,
1328				urb->setup_dma,
1329				sizeof(struct usb_ctrlrequest),
1330				DMA_TO_DEVICE);
1331	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1332		hcd_free_coherent(urb->dev->bus,
1333				&urb->setup_dma,
1334				(void **) &urb->setup_packet,
1335				sizeof(struct usb_ctrlrequest),
1336				DMA_TO_DEVICE);
1337
1338	/* Make it safe to call this routine more than once */
1339	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1340}
1341EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1342
1343static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1344{
1345	if (hcd->driver->unmap_urb_for_dma)
1346		hcd->driver->unmap_urb_for_dma(hcd, urb);
1347	else
1348		usb_hcd_unmap_urb_for_dma(hcd, urb);
1349}
1350
1351void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1352{
1353	enum dma_data_direction dir;
1354
1355	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1356
1357	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1358	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1359	    (urb->transfer_flags & URB_DMA_MAP_SG))
1360		dma_unmap_sg(hcd->self.sysdev,
1361				urb->sg,
1362				urb->num_sgs,
1363				dir);
1364	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1365		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1366		dma_unmap_page(hcd->self.sysdev,
1367				urb->transfer_dma,
1368				urb->transfer_buffer_length,
1369				dir);
1370	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1371		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1372		dma_unmap_single(hcd->self.sysdev,
1373				urb->transfer_dma,
1374				urb->transfer_buffer_length,
1375				dir);
1376	else if (urb->transfer_flags & URB_MAP_LOCAL)
1377		hcd_free_coherent(urb->dev->bus,
1378				&urb->transfer_dma,
1379				&urb->transfer_buffer,
1380				urb->transfer_buffer_length,
1381				dir);
1382
1383	/* Make it safe to call this routine more than once */
1384	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1385			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1386}
1387EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1388
1389static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1390			   gfp_t mem_flags)
1391{
1392	if (hcd->driver->map_urb_for_dma)
1393		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1394	else
1395		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1396}
1397
1398int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1399			    gfp_t mem_flags)
1400{
1401	enum dma_data_direction dir;
1402	int ret = 0;
1403
1404	/* Map the URB's buffers for DMA access.
1405	 * Lower level HCD code should use *_dma exclusively,
1406	 * unless it uses pio or talks to another transport,
1407	 * or uses the provided scatter gather list for bulk.
1408	 */
1409
1410	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1411		if (hcd->self.uses_pio_for_control)
1412			return ret;
1413		if (hcd->localmem_pool) {
1414			ret = hcd_alloc_coherent(
1415					urb->dev->bus, mem_flags,
1416					&urb->setup_dma,
1417					(void **)&urb->setup_packet,
1418					sizeof(struct usb_ctrlrequest),
1419					DMA_TO_DEVICE);
1420			if (ret)
1421				return ret;
1422			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1423		} else if (hcd_uses_dma(hcd)) {
1424			if (object_is_on_stack(urb->setup_packet)) {
1425				WARN_ONCE(1, "setup packet is on stack\n");
1426				return -EAGAIN;
1427			}
1428
1429			urb->setup_dma = dma_map_single(
1430					hcd->self.sysdev,
1431					urb->setup_packet,
1432					sizeof(struct usb_ctrlrequest),
1433					DMA_TO_DEVICE);
1434			if (dma_mapping_error(hcd->self.sysdev,
1435						urb->setup_dma))
1436				return -EAGAIN;
1437			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
 
 
 
 
 
 
 
 
 
 
1438		}
1439	}
1440
1441	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1442	if (urb->transfer_buffer_length != 0
1443	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1444		if (hcd->localmem_pool) {
1445			ret = hcd_alloc_coherent(
1446					urb->dev->bus, mem_flags,
1447					&urb->transfer_dma,
1448					&urb->transfer_buffer,
1449					urb->transfer_buffer_length,
1450					dir);
1451			if (ret == 0)
1452				urb->transfer_flags |= URB_MAP_LOCAL;
1453		} else if (hcd_uses_dma(hcd)) {
1454			if (urb->num_sgs) {
1455				int n;
1456
1457				/* We don't support sg for isoc transfers ! */
1458				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1459					WARN_ON(1);
1460					return -EINVAL;
1461				}
1462
1463				n = dma_map_sg(
1464						hcd->self.sysdev,
1465						urb->sg,
1466						urb->num_sgs,
1467						dir);
1468				if (n <= 0)
1469					ret = -EAGAIN;
1470				else
1471					urb->transfer_flags |= URB_DMA_MAP_SG;
1472				urb->num_mapped_sgs = n;
1473				if (n != urb->num_sgs)
1474					urb->transfer_flags |=
1475							URB_DMA_SG_COMBINED;
1476			} else if (urb->sg) {
1477				struct scatterlist *sg = urb->sg;
1478				urb->transfer_dma = dma_map_page(
1479						hcd->self.sysdev,
1480						sg_page(sg),
1481						sg->offset,
1482						urb->transfer_buffer_length,
1483						dir);
1484				if (dma_mapping_error(hcd->self.sysdev,
1485						urb->transfer_dma))
1486					ret = -EAGAIN;
1487				else
1488					urb->transfer_flags |= URB_DMA_MAP_PAGE;
 
 
 
1489			} else if (object_is_on_stack(urb->transfer_buffer)) {
1490				WARN_ONCE(1, "transfer buffer is on stack\n");
1491				ret = -EAGAIN;
1492			} else {
1493				urb->transfer_dma = dma_map_single(
1494						hcd->self.sysdev,
1495						urb->transfer_buffer,
1496						urb->transfer_buffer_length,
1497						dir);
1498				if (dma_mapping_error(hcd->self.sysdev,
1499						urb->transfer_dma))
1500					ret = -EAGAIN;
1501				else
1502					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1503			}
 
 
 
 
 
 
 
 
 
1504		}
1505		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1506				URB_SETUP_MAP_LOCAL)))
1507			usb_hcd_unmap_urb_for_dma(hcd, urb);
1508	}
1509	return ret;
1510}
1511EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1512
1513/*-------------------------------------------------------------------------*/
1514
1515/* may be called in any context with a valid urb->dev usecount
1516 * caller surrenders "ownership" of urb
1517 * expects usb_submit_urb() to have sanity checked and conditioned all
1518 * inputs in the urb
1519 */
1520int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1521{
1522	int			status;
1523	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1524
1525	/* increment urb's reference count as part of giving it to the HCD
1526	 * (which will control it).  HCD guarantees that it either returns
1527	 * an error or calls giveback(), but not both.
1528	 */
1529	usb_get_urb(urb);
1530	atomic_inc(&urb->use_count);
1531	atomic_inc(&urb->dev->urbnum);
1532	usbmon_urb_submit(&hcd->self, urb);
1533
1534	/* NOTE requirements on root-hub callers (usbfs and the hub
1535	 * driver, for now):  URBs' urb->transfer_buffer must be
1536	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1537	 * they could clobber root hub response data.  Also, control
1538	 * URBs must be submitted in process context with interrupts
1539	 * enabled.
1540	 */
1541
1542	if (is_root_hub(urb->dev)) {
1543		status = rh_urb_enqueue(hcd, urb);
1544	} else {
1545		status = map_urb_for_dma(hcd, urb, mem_flags);
1546		if (likely(status == 0)) {
1547			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1548			if (unlikely(status))
1549				unmap_urb_for_dma(hcd, urb);
1550		}
1551	}
1552
1553	if (unlikely(status)) {
1554		usbmon_urb_submit_error(&hcd->self, urb, status);
1555		urb->hcpriv = NULL;
1556		INIT_LIST_HEAD(&urb->urb_list);
1557		atomic_dec(&urb->use_count);
1558		atomic_dec(&urb->dev->urbnum);
1559		if (atomic_read(&urb->reject))
1560			wake_up(&usb_kill_urb_queue);
1561		usb_put_urb(urb);
1562	}
1563	return status;
1564}
1565
1566/*-------------------------------------------------------------------------*/
1567
1568/* this makes the hcd giveback() the urb more quickly, by kicking it
1569 * off hardware queues (which may take a while) and returning it as
1570 * soon as practical.  we've already set up the urb's return status,
1571 * but we can't know if the callback completed already.
1572 */
1573static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1574{
1575	int		value;
1576
1577	if (is_root_hub(urb->dev))
1578		value = usb_rh_urb_dequeue(hcd, urb, status);
1579	else {
1580
1581		/* The only reason an HCD might fail this call is if
1582		 * it has not yet fully queued the urb to begin with.
1583		 * Such failures should be harmless. */
1584		value = hcd->driver->urb_dequeue(hcd, urb, status);
1585	}
1586	return value;
1587}
1588
1589/*
1590 * called in any context
1591 *
1592 * caller guarantees urb won't be recycled till both unlink()
1593 * and the urb's completion function return
1594 */
1595int usb_hcd_unlink_urb (struct urb *urb, int status)
1596{
1597	struct usb_hcd		*hcd;
1598	struct usb_device	*udev = urb->dev;
1599	int			retval = -EIDRM;
1600	unsigned long		flags;
1601
1602	/* Prevent the device and bus from going away while
1603	 * the unlink is carried out.  If they are already gone
1604	 * then urb->use_count must be 0, since disconnected
1605	 * devices can't have any active URBs.
1606	 */
1607	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1608	if (atomic_read(&urb->use_count) > 0) {
1609		retval = 0;
1610		usb_get_dev(udev);
1611	}
1612	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1613	if (retval == 0) {
1614		hcd = bus_to_hcd(urb->dev->bus);
1615		retval = unlink1(hcd, urb, status);
1616		if (retval == 0)
1617			retval = -EINPROGRESS;
1618		else if (retval != -EIDRM && retval != -EBUSY)
1619			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1620					urb, retval);
1621		usb_put_dev(udev);
1622	}
1623	return retval;
1624}
1625
1626/*-------------------------------------------------------------------------*/
1627
1628static void __usb_hcd_giveback_urb(struct urb *urb)
1629{
1630	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1631	struct usb_anchor *anchor = urb->anchor;
1632	int status = urb->unlinked;
1633
1634	urb->hcpriv = NULL;
1635	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1636	    urb->actual_length < urb->transfer_buffer_length &&
1637	    !status))
1638		status = -EREMOTEIO;
1639
1640	unmap_urb_for_dma(hcd, urb);
1641	usbmon_urb_complete(&hcd->self, urb, status);
1642	usb_anchor_suspend_wakeups(anchor);
1643	usb_unanchor_urb(urb);
1644	if (likely(status == 0))
1645		usb_led_activity(USB_LED_EVENT_HOST);
1646
1647	/* pass ownership to the completion handler */
1648	urb->status = status;
1649	kcov_remote_start_usb((u64)urb->dev->bus->busnum);
1650	urb->complete(urb);
1651	kcov_remote_stop();
1652
1653	usb_anchor_resume_wakeups(anchor);
1654	atomic_dec(&urb->use_count);
1655	if (unlikely(atomic_read(&urb->reject)))
1656		wake_up(&usb_kill_urb_queue);
1657	usb_put_urb(urb);
1658}
1659
1660static void usb_giveback_urb_bh(unsigned long param)
1661{
1662	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1663	struct list_head local_list;
1664
1665	spin_lock_irq(&bh->lock);
1666	bh->running = true;
1667 restart:
1668	list_replace_init(&bh->head, &local_list);
1669	spin_unlock_irq(&bh->lock);
1670
1671	while (!list_empty(&local_list)) {
1672		struct urb *urb;
1673
1674		urb = list_entry(local_list.next, struct urb, urb_list);
1675		list_del_init(&urb->urb_list);
1676		bh->completing_ep = urb->ep;
1677		__usb_hcd_giveback_urb(urb);
1678		bh->completing_ep = NULL;
1679	}
1680
1681	/* check if there are new URBs to giveback */
1682	spin_lock_irq(&bh->lock);
1683	if (!list_empty(&bh->head))
1684		goto restart;
1685	bh->running = false;
1686	spin_unlock_irq(&bh->lock);
1687}
1688
1689/**
1690 * usb_hcd_giveback_urb - return URB from HCD to device driver
1691 * @hcd: host controller returning the URB
1692 * @urb: urb being returned to the USB device driver.
1693 * @status: completion status code for the URB.
1694 * Context: in_interrupt()
1695 *
1696 * This hands the URB from HCD to its USB device driver, using its
1697 * completion function.  The HCD has freed all per-urb resources
1698 * (and is done using urb->hcpriv).  It also released all HCD locks;
1699 * the device driver won't cause problems if it frees, modifies,
1700 * or resubmits this URB.
1701 *
1702 * If @urb was unlinked, the value of @status will be overridden by
1703 * @urb->unlinked.  Erroneous short transfers are detected in case
1704 * the HCD hasn't checked for them.
1705 */
1706void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1707{
1708	struct giveback_urb_bh *bh;
1709	bool running, high_prio_bh;
1710
1711	/* pass status to tasklet via unlinked */
1712	if (likely(!urb->unlinked))
1713		urb->unlinked = status;
1714
1715	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1716		__usb_hcd_giveback_urb(urb);
1717		return;
1718	}
1719
1720	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1721		bh = &hcd->high_prio_bh;
1722		high_prio_bh = true;
1723	} else {
1724		bh = &hcd->low_prio_bh;
1725		high_prio_bh = false;
1726	}
1727
1728	spin_lock(&bh->lock);
1729	list_add_tail(&urb->urb_list, &bh->head);
1730	running = bh->running;
1731	spin_unlock(&bh->lock);
1732
1733	if (running)
1734		;
1735	else if (high_prio_bh)
1736		tasklet_hi_schedule(&bh->bh);
1737	else
1738		tasklet_schedule(&bh->bh);
1739}
1740EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1741
1742/*-------------------------------------------------------------------------*/
1743
1744/* Cancel all URBs pending on this endpoint and wait for the endpoint's
1745 * queue to drain completely.  The caller must first insure that no more
1746 * URBs can be submitted for this endpoint.
1747 */
1748void usb_hcd_flush_endpoint(struct usb_device *udev,
1749		struct usb_host_endpoint *ep)
1750{
1751	struct usb_hcd		*hcd;
1752	struct urb		*urb;
1753
1754	if (!ep)
1755		return;
1756	might_sleep();
1757	hcd = bus_to_hcd(udev->bus);
1758
1759	/* No more submits can occur */
1760	spin_lock_irq(&hcd_urb_list_lock);
1761rescan:
1762	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1763		int	is_in;
1764
1765		if (urb->unlinked)
1766			continue;
1767		usb_get_urb (urb);
1768		is_in = usb_urb_dir_in(urb);
1769		spin_unlock(&hcd_urb_list_lock);
1770
1771		/* kick hcd */
1772		unlink1(hcd, urb, -ESHUTDOWN);
1773		dev_dbg (hcd->self.controller,
1774			"shutdown urb %pK ep%d%s-%s\n",
1775			urb, usb_endpoint_num(&ep->desc),
1776			is_in ? "in" : "out",
1777			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1778		usb_put_urb (urb);
1779
1780		/* list contents may have changed */
1781		spin_lock(&hcd_urb_list_lock);
1782		goto rescan;
1783	}
1784	spin_unlock_irq(&hcd_urb_list_lock);
1785
1786	/* Wait until the endpoint queue is completely empty */
1787	while (!list_empty (&ep->urb_list)) {
1788		spin_lock_irq(&hcd_urb_list_lock);
1789
1790		/* The list may have changed while we acquired the spinlock */
1791		urb = NULL;
1792		if (!list_empty (&ep->urb_list)) {
1793			urb = list_entry (ep->urb_list.prev, struct urb,
1794					urb_list);
1795			usb_get_urb (urb);
1796		}
1797		spin_unlock_irq(&hcd_urb_list_lock);
1798
1799		if (urb) {
1800			usb_kill_urb (urb);
1801			usb_put_urb (urb);
1802		}
1803	}
1804}
1805
1806/**
1807 * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1808 *				the bus bandwidth
1809 * @udev: target &usb_device
1810 * @new_config: new configuration to install
1811 * @cur_alt: the current alternate interface setting
1812 * @new_alt: alternate interface setting that is being installed
1813 *
1814 * To change configurations, pass in the new configuration in new_config,
1815 * and pass NULL for cur_alt and new_alt.
1816 *
1817 * To reset a device's configuration (put the device in the ADDRESSED state),
1818 * pass in NULL for new_config, cur_alt, and new_alt.
1819 *
1820 * To change alternate interface settings, pass in NULL for new_config,
1821 * pass in the current alternate interface setting in cur_alt,
1822 * and pass in the new alternate interface setting in new_alt.
1823 *
1824 * Return: An error if the requested bandwidth change exceeds the
1825 * bus bandwidth or host controller internal resources.
1826 */
1827int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1828		struct usb_host_config *new_config,
1829		struct usb_host_interface *cur_alt,
1830		struct usb_host_interface *new_alt)
1831{
1832	int num_intfs, i, j;
1833	struct usb_host_interface *alt = NULL;
1834	int ret = 0;
1835	struct usb_hcd *hcd;
1836	struct usb_host_endpoint *ep;
1837
1838	hcd = bus_to_hcd(udev->bus);
1839	if (!hcd->driver->check_bandwidth)
1840		return 0;
1841
1842	/* Configuration is being removed - set configuration 0 */
1843	if (!new_config && !cur_alt) {
1844		for (i = 1; i < 16; ++i) {
1845			ep = udev->ep_out[i];
1846			if (ep)
1847				hcd->driver->drop_endpoint(hcd, udev, ep);
1848			ep = udev->ep_in[i];
1849			if (ep)
1850				hcd->driver->drop_endpoint(hcd, udev, ep);
1851		}
1852		hcd->driver->check_bandwidth(hcd, udev);
1853		return 0;
1854	}
1855	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1856	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1857	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1858	 * ok to exclude it.
1859	 */
1860	if (new_config) {
1861		num_intfs = new_config->desc.bNumInterfaces;
1862		/* Remove endpoints (except endpoint 0, which is always on the
1863		 * schedule) from the old config from the schedule
1864		 */
1865		for (i = 1; i < 16; ++i) {
1866			ep = udev->ep_out[i];
1867			if (ep) {
1868				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1869				if (ret < 0)
1870					goto reset;
1871			}
1872			ep = udev->ep_in[i];
1873			if (ep) {
1874				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1875				if (ret < 0)
1876					goto reset;
1877			}
1878		}
1879		for (i = 0; i < num_intfs; ++i) {
1880			struct usb_host_interface *first_alt;
1881			int iface_num;
1882
1883			first_alt = &new_config->intf_cache[i]->altsetting[0];
1884			iface_num = first_alt->desc.bInterfaceNumber;
1885			/* Set up endpoints for alternate interface setting 0 */
1886			alt = usb_find_alt_setting(new_config, iface_num, 0);
1887			if (!alt)
1888				/* No alt setting 0? Pick the first setting. */
1889				alt = first_alt;
1890
1891			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1892				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1893				if (ret < 0)
1894					goto reset;
1895			}
1896		}
1897	}
1898	if (cur_alt && new_alt) {
1899		struct usb_interface *iface = usb_ifnum_to_if(udev,
1900				cur_alt->desc.bInterfaceNumber);
1901
1902		if (!iface)
1903			return -EINVAL;
1904		if (iface->resetting_device) {
1905			/*
1906			 * The USB core just reset the device, so the xHCI host
1907			 * and the device will think alt setting 0 is installed.
1908			 * However, the USB core will pass in the alternate
1909			 * setting installed before the reset as cur_alt.  Dig
1910			 * out the alternate setting 0 structure, or the first
1911			 * alternate setting if a broken device doesn't have alt
1912			 * setting 0.
1913			 */
1914			cur_alt = usb_altnum_to_altsetting(iface, 0);
1915			if (!cur_alt)
1916				cur_alt = &iface->altsetting[0];
1917		}
1918
1919		/* Drop all the endpoints in the current alt setting */
1920		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1921			ret = hcd->driver->drop_endpoint(hcd, udev,
1922					&cur_alt->endpoint[i]);
1923			if (ret < 0)
1924				goto reset;
1925		}
1926		/* Add all the endpoints in the new alt setting */
1927		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1928			ret = hcd->driver->add_endpoint(hcd, udev,
1929					&new_alt->endpoint[i]);
1930			if (ret < 0)
1931				goto reset;
1932		}
1933	}
1934	ret = hcd->driver->check_bandwidth(hcd, udev);
1935reset:
1936	if (ret < 0)
1937		hcd->driver->reset_bandwidth(hcd, udev);
1938	return ret;
1939}
1940
1941/* Disables the endpoint: synchronizes with the hcd to make sure all
1942 * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1943 * have been called previously.  Use for set_configuration, set_interface,
1944 * driver removal, physical disconnect.
1945 *
1946 * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1947 * type, maxpacket size, toggle, halt status, and scheduling.
1948 */
1949void usb_hcd_disable_endpoint(struct usb_device *udev,
1950		struct usb_host_endpoint *ep)
1951{
1952	struct usb_hcd		*hcd;
1953
1954	might_sleep();
1955	hcd = bus_to_hcd(udev->bus);
1956	if (hcd->driver->endpoint_disable)
1957		hcd->driver->endpoint_disable(hcd, ep);
1958}
1959
1960/**
1961 * usb_hcd_reset_endpoint - reset host endpoint state
1962 * @udev: USB device.
1963 * @ep:   the endpoint to reset.
1964 *
1965 * Resets any host endpoint state such as the toggle bit, sequence
1966 * number and current window.
1967 */
1968void usb_hcd_reset_endpoint(struct usb_device *udev,
1969			    struct usb_host_endpoint *ep)
1970{
1971	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1972
1973	if (hcd->driver->endpoint_reset)
1974		hcd->driver->endpoint_reset(hcd, ep);
1975	else {
1976		int epnum = usb_endpoint_num(&ep->desc);
1977		int is_out = usb_endpoint_dir_out(&ep->desc);
1978		int is_control = usb_endpoint_xfer_control(&ep->desc);
1979
1980		usb_settoggle(udev, epnum, is_out, 0);
1981		if (is_control)
1982			usb_settoggle(udev, epnum, !is_out, 0);
1983	}
1984}
1985
1986/**
1987 * usb_alloc_streams - allocate bulk endpoint stream IDs.
1988 * @interface:		alternate setting that includes all endpoints.
1989 * @eps:		array of endpoints that need streams.
1990 * @num_eps:		number of endpoints in the array.
1991 * @num_streams:	number of streams to allocate.
1992 * @mem_flags:		flags hcd should use to allocate memory.
1993 *
1994 * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
1995 * Drivers may queue multiple transfers to different stream IDs, which may
1996 * complete in a different order than they were queued.
1997 *
1998 * Return: On success, the number of allocated streams. On failure, a negative
1999 * error code.
2000 */
2001int usb_alloc_streams(struct usb_interface *interface,
2002		struct usb_host_endpoint **eps, unsigned int num_eps,
2003		unsigned int num_streams, gfp_t mem_flags)
2004{
2005	struct usb_hcd *hcd;
2006	struct usb_device *dev;
2007	int i, ret;
2008
2009	dev = interface_to_usbdev(interface);
2010	hcd = bus_to_hcd(dev->bus);
2011	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2012		return -EINVAL;
2013	if (dev->speed < USB_SPEED_SUPER)
2014		return -EINVAL;
2015	if (dev->state < USB_STATE_CONFIGURED)
2016		return -ENODEV;
2017
2018	for (i = 0; i < num_eps; i++) {
2019		/* Streams only apply to bulk endpoints. */
2020		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2021			return -EINVAL;
2022		/* Re-alloc is not allowed */
2023		if (eps[i]->streams)
2024			return -EINVAL;
2025	}
2026
2027	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2028			num_streams, mem_flags);
2029	if (ret < 0)
2030		return ret;
2031
2032	for (i = 0; i < num_eps; i++)
2033		eps[i]->streams = ret;
2034
2035	return ret;
2036}
2037EXPORT_SYMBOL_GPL(usb_alloc_streams);
2038
2039/**
2040 * usb_free_streams - free bulk endpoint stream IDs.
2041 * @interface:	alternate setting that includes all endpoints.
2042 * @eps:	array of endpoints to remove streams from.
2043 * @num_eps:	number of endpoints in the array.
2044 * @mem_flags:	flags hcd should use to allocate memory.
2045 *
2046 * Reverts a group of bulk endpoints back to not using stream IDs.
2047 * Can fail if we are given bad arguments, or HCD is broken.
2048 *
2049 * Return: 0 on success. On failure, a negative error code.
2050 */
2051int usb_free_streams(struct usb_interface *interface,
2052		struct usb_host_endpoint **eps, unsigned int num_eps,
2053		gfp_t mem_flags)
2054{
2055	struct usb_hcd *hcd;
2056	struct usb_device *dev;
2057	int i, ret;
2058
2059	dev = interface_to_usbdev(interface);
2060	hcd = bus_to_hcd(dev->bus);
2061	if (dev->speed < USB_SPEED_SUPER)
2062		return -EINVAL;
2063
2064	/* Double-free is not allowed */
2065	for (i = 0; i < num_eps; i++)
2066		if (!eps[i] || !eps[i]->streams)
2067			return -EINVAL;
2068
2069	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2070	if (ret < 0)
2071		return ret;
2072
2073	for (i = 0; i < num_eps; i++)
2074		eps[i]->streams = 0;
2075
2076	return ret;
2077}
2078EXPORT_SYMBOL_GPL(usb_free_streams);
2079
2080/* Protect against drivers that try to unlink URBs after the device
2081 * is gone, by waiting until all unlinks for @udev are finished.
2082 * Since we don't currently track URBs by device, simply wait until
2083 * nothing is running in the locked region of usb_hcd_unlink_urb().
2084 */
2085void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2086{
2087	spin_lock_irq(&hcd_urb_unlink_lock);
2088	spin_unlock_irq(&hcd_urb_unlink_lock);
2089}
2090
2091/*-------------------------------------------------------------------------*/
2092
2093/* called in any context */
2094int usb_hcd_get_frame_number (struct usb_device *udev)
2095{
2096	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2097
2098	if (!HCD_RH_RUNNING(hcd))
2099		return -ESHUTDOWN;
2100	return hcd->driver->get_frame_number (hcd);
2101}
2102
2103/*-------------------------------------------------------------------------*/
2104
2105#ifdef	CONFIG_PM
2106
2107int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2108{
2109	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2110	int		status;
2111	int		old_state = hcd->state;
2112
2113	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2114			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2115			rhdev->do_remote_wakeup);
2116	if (HCD_DEAD(hcd)) {
2117		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2118		return 0;
2119	}
2120
2121	if (!hcd->driver->bus_suspend) {
2122		status = -ENOENT;
2123	} else {
2124		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2125		hcd->state = HC_STATE_QUIESCING;
2126		status = hcd->driver->bus_suspend(hcd);
2127	}
2128	if (status == 0) {
2129		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2130		hcd->state = HC_STATE_SUSPENDED;
2131
2132		if (!PMSG_IS_AUTO(msg))
2133			usb_phy_roothub_suspend(hcd->self.sysdev,
2134						hcd->phy_roothub);
2135
2136		/* Did we race with a root-hub wakeup event? */
2137		if (rhdev->do_remote_wakeup) {
2138			char	buffer[6];
2139
2140			status = hcd->driver->hub_status_data(hcd, buffer);
2141			if (status != 0) {
2142				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2143				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2144				status = -EBUSY;
2145			}
2146		}
2147	} else {
2148		spin_lock_irq(&hcd_root_hub_lock);
2149		if (!HCD_DEAD(hcd)) {
2150			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2151			hcd->state = old_state;
2152		}
2153		spin_unlock_irq(&hcd_root_hub_lock);
2154		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2155				"suspend", status);
2156	}
2157	return status;
2158}
2159
2160int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2161{
2162	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2163	int		status;
2164	int		old_state = hcd->state;
2165
2166	dev_dbg(&rhdev->dev, "usb %sresume\n",
2167			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2168	if (HCD_DEAD(hcd)) {
2169		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2170		return 0;
2171	}
2172
2173	if (!PMSG_IS_AUTO(msg)) {
2174		status = usb_phy_roothub_resume(hcd->self.sysdev,
2175						hcd->phy_roothub);
2176		if (status)
2177			return status;
2178	}
2179
2180	if (!hcd->driver->bus_resume)
2181		return -ENOENT;
2182	if (HCD_RH_RUNNING(hcd))
2183		return 0;
2184
2185	hcd->state = HC_STATE_RESUMING;
2186	status = hcd->driver->bus_resume(hcd);
2187	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2188	if (status == 0)
2189		status = usb_phy_roothub_calibrate(hcd->phy_roothub);
2190
2191	if (status == 0) {
2192		struct usb_device *udev;
2193		int port1;
2194
2195		spin_lock_irq(&hcd_root_hub_lock);
2196		if (!HCD_DEAD(hcd)) {
2197			usb_set_device_state(rhdev, rhdev->actconfig
2198					? USB_STATE_CONFIGURED
2199					: USB_STATE_ADDRESS);
2200			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2201			hcd->state = HC_STATE_RUNNING;
2202		}
2203		spin_unlock_irq(&hcd_root_hub_lock);
2204
2205		/*
2206		 * Check whether any of the enabled ports on the root hub are
2207		 * unsuspended.  If they are then a TRSMRCY delay is needed
2208		 * (this is what the USB-2 spec calls a "global resume").
2209		 * Otherwise we can skip the delay.
2210		 */
2211		usb_hub_for_each_child(rhdev, port1, udev) {
2212			if (udev->state != USB_STATE_NOTATTACHED &&
2213					!udev->port_is_suspended) {
2214				usleep_range(10000, 11000);	/* TRSMRCY */
2215				break;
2216			}
2217		}
2218	} else {
2219		hcd->state = old_state;
2220		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2221		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2222				"resume", status);
2223		if (status != -ESHUTDOWN)
2224			usb_hc_died(hcd);
2225	}
2226	return status;
2227}
2228
2229/* Workqueue routine for root-hub remote wakeup */
2230static void hcd_resume_work(struct work_struct *work)
2231{
2232	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2233	struct usb_device *udev = hcd->self.root_hub;
2234
2235	usb_remote_wakeup(udev);
2236}
2237
2238/**
2239 * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2240 * @hcd: host controller for this root hub
2241 *
2242 * The USB host controller calls this function when its root hub is
2243 * suspended (with the remote wakeup feature enabled) and a remote
2244 * wakeup request is received.  The routine submits a workqueue request
2245 * to resume the root hub (that is, manage its downstream ports again).
2246 */
2247void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2248{
2249	unsigned long flags;
2250
2251	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2252	if (hcd->rh_registered) {
2253		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2254		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2255		queue_work(pm_wq, &hcd->wakeup_work);
2256	}
2257	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2258}
2259EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2260
2261#endif	/* CONFIG_PM */
2262
2263/*-------------------------------------------------------------------------*/
2264
2265#ifdef	CONFIG_USB_OTG
2266
2267/**
2268 * usb_bus_start_enum - start immediate enumeration (for OTG)
2269 * @bus: the bus (must use hcd framework)
2270 * @port_num: 1-based number of port; usually bus->otg_port
2271 * Context: in_interrupt()
2272 *
2273 * Starts enumeration, with an immediate reset followed later by
2274 * hub_wq identifying and possibly configuring the device.
2275 * This is needed by OTG controller drivers, where it helps meet
2276 * HNP protocol timing requirements for starting a port reset.
2277 *
2278 * Return: 0 if successful.
2279 */
2280int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2281{
2282	struct usb_hcd		*hcd;
2283	int			status = -EOPNOTSUPP;
2284
2285	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2286	 * boards with root hubs hooked up to internal devices (instead of
2287	 * just the OTG port) may need more attention to resetting...
2288	 */
2289	hcd = bus_to_hcd(bus);
2290	if (port_num && hcd->driver->start_port_reset)
2291		status = hcd->driver->start_port_reset(hcd, port_num);
2292
2293	/* allocate hub_wq shortly after (first) root port reset finishes;
2294	 * it may issue others, until at least 50 msecs have passed.
2295	 */
2296	if (status == 0)
2297		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2298	return status;
2299}
2300EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2301
2302#endif
2303
2304/*-------------------------------------------------------------------------*/
2305
2306/**
2307 * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2308 * @irq: the IRQ being raised
2309 * @__hcd: pointer to the HCD whose IRQ is being signaled
2310 *
2311 * If the controller isn't HALTed, calls the driver's irq handler.
2312 * Checks whether the controller is now dead.
2313 *
2314 * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2315 */
2316irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2317{
2318	struct usb_hcd		*hcd = __hcd;
2319	irqreturn_t		rc;
2320
2321	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2322		rc = IRQ_NONE;
2323	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2324		rc = IRQ_NONE;
2325	else
2326		rc = IRQ_HANDLED;
2327
2328	return rc;
2329}
2330EXPORT_SYMBOL_GPL(usb_hcd_irq);
2331
2332/*-------------------------------------------------------------------------*/
2333
2334/* Workqueue routine for when the root-hub has died. */
2335static void hcd_died_work(struct work_struct *work)
2336{
2337	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2338	static char *env[] = {
2339		"ERROR=DEAD",
2340		NULL
2341	};
2342
2343	/* Notify user space that the host controller has died */
2344	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2345}
2346
2347/**
2348 * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2349 * @hcd: pointer to the HCD representing the controller
2350 *
2351 * This is called by bus glue to report a USB host controller that died
2352 * while operations may still have been pending.  It's called automatically
2353 * by the PCI glue, so only glue for non-PCI busses should need to call it.
2354 *
2355 * Only call this function with the primary HCD.
2356 */
2357void usb_hc_died (struct usb_hcd *hcd)
2358{
2359	unsigned long flags;
2360
2361	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2362
2363	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2364	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2365	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2366	if (hcd->rh_registered) {
2367		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2368
2369		/* make hub_wq clean up old urbs and devices */
2370		usb_set_device_state (hcd->self.root_hub,
2371				USB_STATE_NOTATTACHED);
2372		usb_kick_hub_wq(hcd->self.root_hub);
2373	}
2374	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2375		hcd = hcd->shared_hcd;
2376		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2377		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2378		if (hcd->rh_registered) {
2379			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2380
2381			/* make hub_wq clean up old urbs and devices */
2382			usb_set_device_state(hcd->self.root_hub,
2383					USB_STATE_NOTATTACHED);
2384			usb_kick_hub_wq(hcd->self.root_hub);
2385		}
2386	}
2387
2388	/* Handle the case where this function gets called with a shared HCD */
2389	if (usb_hcd_is_primary_hcd(hcd))
2390		schedule_work(&hcd->died_work);
2391	else
2392		schedule_work(&hcd->primary_hcd->died_work);
2393
2394	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2395	/* Make sure that the other roothub is also deallocated. */
2396}
2397EXPORT_SYMBOL_GPL (usb_hc_died);
2398
2399/*-------------------------------------------------------------------------*/
2400
2401static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2402{
2403
2404	spin_lock_init(&bh->lock);
2405	INIT_LIST_HEAD(&bh->head);
2406	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2407}
2408
2409struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2410		struct device *sysdev, struct device *dev, const char *bus_name,
2411		struct usb_hcd *primary_hcd)
2412{
2413	struct usb_hcd *hcd;
2414
2415	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2416	if (!hcd)
2417		return NULL;
2418	if (primary_hcd == NULL) {
2419		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2420				GFP_KERNEL);
2421		if (!hcd->address0_mutex) {
2422			kfree(hcd);
2423			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2424			return NULL;
2425		}
2426		mutex_init(hcd->address0_mutex);
2427		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2428				GFP_KERNEL);
2429		if (!hcd->bandwidth_mutex) {
2430			kfree(hcd->address0_mutex);
2431			kfree(hcd);
2432			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2433			return NULL;
2434		}
2435		mutex_init(hcd->bandwidth_mutex);
2436		dev_set_drvdata(dev, hcd);
2437	} else {
2438		mutex_lock(&usb_port_peer_mutex);
2439		hcd->address0_mutex = primary_hcd->address0_mutex;
2440		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2441		hcd->primary_hcd = primary_hcd;
2442		primary_hcd->primary_hcd = primary_hcd;
2443		hcd->shared_hcd = primary_hcd;
2444		primary_hcd->shared_hcd = hcd;
2445		mutex_unlock(&usb_port_peer_mutex);
2446	}
2447
2448	kref_init(&hcd->kref);
2449
2450	usb_bus_init(&hcd->self);
2451	hcd->self.controller = dev;
2452	hcd->self.sysdev = sysdev;
2453	hcd->self.bus_name = bus_name;
2454
2455	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2456#ifdef CONFIG_PM
2457	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2458#endif
2459
2460	INIT_WORK(&hcd->died_work, hcd_died_work);
2461
2462	hcd->driver = driver;
2463	hcd->speed = driver->flags & HCD_MASK;
2464	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2465			"USB Host Controller";
2466	return hcd;
2467}
2468EXPORT_SYMBOL_GPL(__usb_create_hcd);
2469
2470/**
2471 * usb_create_shared_hcd - create and initialize an HCD structure
2472 * @driver: HC driver that will use this hcd
2473 * @dev: device for this HC, stored in hcd->self.controller
2474 * @bus_name: value to store in hcd->self.bus_name
2475 * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2476 *              PCI device.  Only allocate certain resources for the primary HCD
2477 * Context: !in_interrupt()
2478 *
2479 * Allocate a struct usb_hcd, with extra space at the end for the
2480 * HC driver's private data.  Initialize the generic members of the
2481 * hcd structure.
2482 *
2483 * Return: On success, a pointer to the created and initialized HCD structure.
2484 * On failure (e.g. if memory is unavailable), %NULL.
2485 */
2486struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2487		struct device *dev, const char *bus_name,
2488		struct usb_hcd *primary_hcd)
2489{
2490	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2491}
2492EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2493
2494/**
2495 * usb_create_hcd - create and initialize an HCD structure
2496 * @driver: HC driver that will use this hcd
2497 * @dev: device for this HC, stored in hcd->self.controller
2498 * @bus_name: value to store in hcd->self.bus_name
2499 * Context: !in_interrupt()
2500 *
2501 * Allocate a struct usb_hcd, with extra space at the end for the
2502 * HC driver's private data.  Initialize the generic members of the
2503 * hcd structure.
2504 *
2505 * Return: On success, a pointer to the created and initialized HCD
2506 * structure. On failure (e.g. if memory is unavailable), %NULL.
2507 */
2508struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2509		struct device *dev, const char *bus_name)
2510{
2511	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2512}
2513EXPORT_SYMBOL_GPL(usb_create_hcd);
2514
2515/*
2516 * Roothubs that share one PCI device must also share the bandwidth mutex.
2517 * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2518 * deallocated.
2519 *
2520 * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2521 * freed.  When hcd_release() is called for either hcd in a peer set,
2522 * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2523 */
2524static void hcd_release(struct kref *kref)
2525{
2526	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2527
2528	mutex_lock(&usb_port_peer_mutex);
2529	if (hcd->shared_hcd) {
2530		struct usb_hcd *peer = hcd->shared_hcd;
2531
2532		peer->shared_hcd = NULL;
2533		peer->primary_hcd = NULL;
2534	} else {
2535		kfree(hcd->address0_mutex);
2536		kfree(hcd->bandwidth_mutex);
2537	}
2538	mutex_unlock(&usb_port_peer_mutex);
2539	kfree(hcd);
2540}
2541
2542struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2543{
2544	if (hcd)
2545		kref_get (&hcd->kref);
2546	return hcd;
2547}
2548EXPORT_SYMBOL_GPL(usb_get_hcd);
2549
2550void usb_put_hcd (struct usb_hcd *hcd)
2551{
2552	if (hcd)
2553		kref_put (&hcd->kref, hcd_release);
2554}
2555EXPORT_SYMBOL_GPL(usb_put_hcd);
2556
2557int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2558{
2559	if (!hcd->primary_hcd)
2560		return 1;
2561	return hcd == hcd->primary_hcd;
2562}
2563EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2564
2565int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2566{
2567	if (!hcd->driver->find_raw_port_number)
2568		return port1;
2569
2570	return hcd->driver->find_raw_port_number(hcd, port1);
2571}
2572
2573static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2574		unsigned int irqnum, unsigned long irqflags)
2575{
2576	int retval;
2577
2578	if (hcd->driver->irq) {
2579
2580		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2581				hcd->driver->description, hcd->self.busnum);
2582		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2583				hcd->irq_descr, hcd);
2584		if (retval != 0) {
2585			dev_err(hcd->self.controller,
2586					"request interrupt %d failed\n",
2587					irqnum);
2588			return retval;
2589		}
2590		hcd->irq = irqnum;
2591		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2592				(hcd->driver->flags & HCD_MEMORY) ?
2593					"io mem" : "io base",
2594					(unsigned long long)hcd->rsrc_start);
2595	} else {
2596		hcd->irq = 0;
2597		if (hcd->rsrc_start)
2598			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2599					(hcd->driver->flags & HCD_MEMORY) ?
2600					"io mem" : "io base",
2601					(unsigned long long)hcd->rsrc_start);
2602	}
2603	return 0;
2604}
2605
2606/*
2607 * Before we free this root hub, flush in-flight peering attempts
2608 * and disable peer lookups
2609 */
2610static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2611{
2612	struct usb_device *rhdev;
2613
2614	mutex_lock(&usb_port_peer_mutex);
2615	rhdev = hcd->self.root_hub;
2616	hcd->self.root_hub = NULL;
2617	mutex_unlock(&usb_port_peer_mutex);
2618	usb_put_dev(rhdev);
2619}
2620
2621/**
2622 * usb_add_hcd - finish generic HCD structure initialization and register
2623 * @hcd: the usb_hcd structure to initialize
2624 * @irqnum: Interrupt line to allocate
2625 * @irqflags: Interrupt type flags
2626 *
2627 * Finish the remaining parts of generic HCD initialization: allocate the
2628 * buffers of consistent memory, register the bus, request the IRQ line,
2629 * and call the driver's reset() and start() routines.
2630 */
2631int usb_add_hcd(struct usb_hcd *hcd,
2632		unsigned int irqnum, unsigned long irqflags)
2633{
2634	int retval;
2635	struct usb_device *rhdev;
2636
2637	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2638		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2639		if (IS_ERR(hcd->phy_roothub))
2640			return PTR_ERR(hcd->phy_roothub);
2641
2642		retval = usb_phy_roothub_init(hcd->phy_roothub);
2643		if (retval)
2644			return retval;
2645
2646		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2647						  PHY_MODE_USB_HOST_SS);
2648		if (retval)
2649			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2650							  PHY_MODE_USB_HOST);
2651		if (retval)
2652			goto err_usb_phy_roothub_power_on;
2653
2654		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2655		if (retval)
2656			goto err_usb_phy_roothub_power_on;
2657	}
2658
2659	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2660
2661	switch (authorized_default) {
2662	case USB_AUTHORIZE_NONE:
2663		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2664		break;
2665
2666	case USB_AUTHORIZE_ALL:
2667		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2668		break;
2669
2670	case USB_AUTHORIZE_INTERNAL:
2671		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2672		break;
2673
2674	case USB_AUTHORIZE_WIRED:
2675	default:
2676		hcd->dev_policy = hcd->wireless ?
2677			USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL;
2678		break;
2679	}
2680
2681	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2682
2683	/* per default all interfaces are authorized */
2684	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2685
2686	/* HC is in reset state, but accessible.  Now do the one-time init,
2687	 * bottom up so that hcds can customize the root hubs before hub_wq
2688	 * starts talking to them.  (Note, bus id is assigned early too.)
2689	 */
2690	retval = hcd_buffer_create(hcd);
2691	if (retval != 0) {
2692		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2693		goto err_create_buf;
2694	}
2695
2696	retval = usb_register_bus(&hcd->self);
2697	if (retval < 0)
2698		goto err_register_bus;
2699
2700	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2701	if (rhdev == NULL) {
2702		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2703		retval = -ENOMEM;
2704		goto err_allocate_root_hub;
2705	}
2706	mutex_lock(&usb_port_peer_mutex);
2707	hcd->self.root_hub = rhdev;
2708	mutex_unlock(&usb_port_peer_mutex);
2709
2710	rhdev->rx_lanes = 1;
2711	rhdev->tx_lanes = 1;
2712
2713	switch (hcd->speed) {
2714	case HCD_USB11:
2715		rhdev->speed = USB_SPEED_FULL;
2716		break;
2717	case HCD_USB2:
2718		rhdev->speed = USB_SPEED_HIGH;
2719		break;
2720	case HCD_USB25:
2721		rhdev->speed = USB_SPEED_WIRELESS;
2722		break;
2723	case HCD_USB3:
2724		rhdev->speed = USB_SPEED_SUPER;
2725		break;
2726	case HCD_USB32:
2727		rhdev->rx_lanes = 2;
2728		rhdev->tx_lanes = 2;
2729		fallthrough;
2730	case HCD_USB31:
2731		rhdev->speed = USB_SPEED_SUPER_PLUS;
2732		break;
2733	default:
2734		retval = -EINVAL;
2735		goto err_set_rh_speed;
2736	}
2737
2738	/* wakeup flag init defaults to "everything works" for root hubs,
2739	 * but drivers can override it in reset() if needed, along with
2740	 * recording the overall controller's system wakeup capability.
2741	 */
2742	device_set_wakeup_capable(&rhdev->dev, 1);
2743
2744	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2745	 * registered.  But since the controller can die at any time,
2746	 * let's initialize the flag before touching the hardware.
2747	 */
2748	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2749
2750	/* "reset" is misnamed; its role is now one-time init. the controller
2751	 * should already have been reset (and boot firmware kicked off etc).
2752	 */
2753	if (hcd->driver->reset) {
2754		retval = hcd->driver->reset(hcd);
2755		if (retval < 0) {
2756			dev_err(hcd->self.controller, "can't setup: %d\n",
2757					retval);
2758			goto err_hcd_driver_setup;
2759		}
2760	}
2761	hcd->rh_pollable = 1;
2762
2763	retval = usb_phy_roothub_calibrate(hcd->phy_roothub);
2764	if (retval)
2765		goto err_hcd_driver_setup;
2766
2767	/* NOTE: root hub and controller capabilities may not be the same */
2768	if (device_can_wakeup(hcd->self.controller)
2769			&& device_can_wakeup(&hcd->self.root_hub->dev))
2770		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2771
2772	/* initialize tasklets */
2773	init_giveback_urb_bh(&hcd->high_prio_bh);
2774	init_giveback_urb_bh(&hcd->low_prio_bh);
2775
2776	/* enable irqs just before we start the controller,
2777	 * if the BIOS provides legacy PCI irqs.
2778	 */
2779	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2780		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2781		if (retval)
2782			goto err_request_irq;
2783	}
2784
2785	hcd->state = HC_STATE_RUNNING;
2786	retval = hcd->driver->start(hcd);
2787	if (retval < 0) {
2788		dev_err(hcd->self.controller, "startup error %d\n", retval);
2789		goto err_hcd_driver_start;
2790	}
2791
2792	/* starting here, usbcore will pay attention to this root hub */
2793	retval = register_root_hub(hcd);
2794	if (retval != 0)
2795		goto err_register_root_hub;
2796
2797	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2798		usb_hcd_poll_rh_status(hcd);
2799
2800	return retval;
2801
2802err_register_root_hub:
2803	hcd->rh_pollable = 0;
2804	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2805	del_timer_sync(&hcd->rh_timer);
2806	hcd->driver->stop(hcd);
2807	hcd->state = HC_STATE_HALT;
2808	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2809	del_timer_sync(&hcd->rh_timer);
2810err_hcd_driver_start:
2811	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2812		free_irq(irqnum, hcd);
2813err_request_irq:
2814err_hcd_driver_setup:
2815err_set_rh_speed:
2816	usb_put_invalidate_rhdev(hcd);
2817err_allocate_root_hub:
2818	usb_deregister_bus(&hcd->self);
2819err_register_bus:
2820	hcd_buffer_destroy(hcd);
2821err_create_buf:
2822	usb_phy_roothub_power_off(hcd->phy_roothub);
2823err_usb_phy_roothub_power_on:
2824	usb_phy_roothub_exit(hcd->phy_roothub);
2825
2826	return retval;
2827}
2828EXPORT_SYMBOL_GPL(usb_add_hcd);
2829
2830/**
2831 * usb_remove_hcd - shutdown processing for generic HCDs
2832 * @hcd: the usb_hcd structure to remove
2833 * Context: !in_interrupt()
2834 *
2835 * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2836 * invoking the HCD's stop() method.
2837 */
2838void usb_remove_hcd(struct usb_hcd *hcd)
2839{
2840	struct usb_device *rhdev = hcd->self.root_hub;
2841
2842	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2843
2844	usb_get_dev(rhdev);
2845	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2846	if (HC_IS_RUNNING (hcd->state))
2847		hcd->state = HC_STATE_QUIESCING;
2848
2849	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2850	spin_lock_irq (&hcd_root_hub_lock);
2851	hcd->rh_registered = 0;
2852	spin_unlock_irq (&hcd_root_hub_lock);
2853
2854#ifdef CONFIG_PM
2855	cancel_work_sync(&hcd->wakeup_work);
2856#endif
2857	cancel_work_sync(&hcd->died_work);
2858
2859	mutex_lock(&usb_bus_idr_lock);
2860	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2861	mutex_unlock(&usb_bus_idr_lock);
2862
2863	/*
2864	 * tasklet_kill() isn't needed here because:
2865	 * - driver's disconnect() called from usb_disconnect() should
2866	 *   make sure its URBs are completed during the disconnect()
2867	 *   callback
2868	 *
2869	 * - it is too late to run complete() here since driver may have
2870	 *   been removed already now
2871	 */
2872
2873	/* Prevent any more root-hub status calls from the timer.
2874	 * The HCD might still restart the timer (if a port status change
2875	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2876	 * the hub_status_data() callback.
2877	 */
2878	hcd->rh_pollable = 0;
2879	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2880	del_timer_sync(&hcd->rh_timer);
2881
2882	hcd->driver->stop(hcd);
2883	hcd->state = HC_STATE_HALT;
2884
2885	/* In case the HCD restarted the timer, stop it again. */
2886	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2887	del_timer_sync(&hcd->rh_timer);
2888
2889	if (usb_hcd_is_primary_hcd(hcd)) {
2890		if (hcd->irq > 0)
2891			free_irq(hcd->irq, hcd);
2892	}
2893
2894	usb_deregister_bus(&hcd->self);
2895	hcd_buffer_destroy(hcd);
2896
2897	usb_phy_roothub_power_off(hcd->phy_roothub);
2898	usb_phy_roothub_exit(hcd->phy_roothub);
2899
2900	usb_put_invalidate_rhdev(hcd);
2901	hcd->flags = 0;
2902}
2903EXPORT_SYMBOL_GPL(usb_remove_hcd);
2904
2905void
2906usb_hcd_platform_shutdown(struct platform_device *dev)
2907{
2908	struct usb_hcd *hcd = platform_get_drvdata(dev);
2909
2910	/* No need for pm_runtime_put(), we're shutting down */
2911	pm_runtime_get_sync(&dev->dev);
2912
2913	if (hcd->driver->shutdown)
2914		hcd->driver->shutdown(hcd);
2915}
2916EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2917
2918int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
2919			    dma_addr_t dma, size_t size)
2920{
2921	int err;
2922	void *local_mem;
2923
2924	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
2925						  dev_to_node(hcd->self.sysdev),
2926						  dev_name(hcd->self.sysdev));
2927	if (IS_ERR(hcd->localmem_pool))
2928		return PTR_ERR(hcd->localmem_pool);
2929
2930	local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
2931				  size, MEMREMAP_WC);
2932	if (IS_ERR(local_mem))
2933		return PTR_ERR(local_mem);
2934
2935	/*
2936	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
2937	 * It's not backed by system memory and thus there's no kernel mapping
2938	 * for it.
2939	 */
2940	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
2941				dma, size, dev_to_node(hcd->self.sysdev));
2942	if (err < 0) {
2943		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
2944			err);
2945		return err;
2946	}
2947
2948	return 0;
2949}
2950EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
2951
2952/*-------------------------------------------------------------------------*/
2953
2954#if IS_ENABLED(CONFIG_USB_MON)
2955
2956const struct usb_mon_operations *mon_ops;
2957
2958/*
2959 * The registration is unlocked.
2960 * We do it this way because we do not want to lock in hot paths.
2961 *
2962 * Notice that the code is minimally error-proof. Because usbmon needs
2963 * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2964 */
2965
2966int usb_mon_register(const struct usb_mon_operations *ops)
2967{
2968
2969	if (mon_ops)
2970		return -EBUSY;
2971
2972	mon_ops = ops;
2973	mb();
2974	return 0;
2975}
2976EXPORT_SYMBOL_GPL (usb_mon_register);
2977
2978void usb_mon_deregister (void)
2979{
2980
2981	if (mon_ops == NULL) {
2982		printk(KERN_ERR "USB: monitor was not registered\n");
2983		return;
2984	}
2985	mon_ops = NULL;
2986	mb();
2987}
2988EXPORT_SYMBOL_GPL (usb_mon_deregister);
2989
2990#endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */
v5.4
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * (C) Copyright Linus Torvalds 1999
   4 * (C) Copyright Johannes Erdfelt 1999-2001
   5 * (C) Copyright Andreas Gal 1999
   6 * (C) Copyright Gregory P. Smith 1999
   7 * (C) Copyright Deti Fliegl 1999
   8 * (C) Copyright Randy Dunlap 2000
   9 * (C) Copyright David Brownell 2000-2002
  10 */
  11
  12#include <linux/bcd.h>
  13#include <linux/module.h>
  14#include <linux/version.h>
  15#include <linux/kernel.h>
  16#include <linux/sched/task_stack.h>
  17#include <linux/slab.h>
  18#include <linux/completion.h>
  19#include <linux/utsname.h>
  20#include <linux/mm.h>
  21#include <asm/io.h>
  22#include <linux/device.h>
  23#include <linux/dma-mapping.h>
  24#include <linux/mutex.h>
  25#include <asm/irq.h>
  26#include <asm/byteorder.h>
  27#include <asm/unaligned.h>
  28#include <linux/platform_device.h>
  29#include <linux/workqueue.h>
  30#include <linux/pm_runtime.h>
  31#include <linux/types.h>
  32#include <linux/genalloc.h>
  33#include <linux/io.h>
 
  34
  35#include <linux/phy/phy.h>
  36#include <linux/usb.h>
  37#include <linux/usb/hcd.h>
  38#include <linux/usb/otg.h>
  39
  40#include "usb.h"
  41#include "phy.h"
  42
  43
  44/*-------------------------------------------------------------------------*/
  45
  46/*
  47 * USB Host Controller Driver framework
  48 *
  49 * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing
  50 * HCD-specific behaviors/bugs.
  51 *
  52 * This does error checks, tracks devices and urbs, and delegates to a
  53 * "hc_driver" only for code (and data) that really needs to know about
  54 * hardware differences.  That includes root hub registers, i/o queues,
  55 * and so on ... but as little else as possible.
  56 *
  57 * Shared code includes most of the "root hub" code (these are emulated,
  58 * though each HC's hardware works differently) and PCI glue, plus request
  59 * tracking overhead.  The HCD code should only block on spinlocks or on
  60 * hardware handshaking; blocking on software events (such as other kernel
  61 * threads releasing resources, or completing actions) is all generic.
  62 *
  63 * Happens the USB 2.0 spec says this would be invisible inside the "USBD",
  64 * and includes mostly a "HCDI" (HCD Interface) along with some APIs used
  65 * only by the hub driver ... and that neither should be seen or used by
  66 * usb client device drivers.
  67 *
  68 * Contributors of ideas or unattributed patches include: David Brownell,
  69 * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ...
  70 *
  71 * HISTORY:
  72 * 2002-02-21	Pull in most of the usb_bus support from usb.c; some
  73 *		associated cleanup.  "usb_hcd" still != "usb_bus".
  74 * 2001-12-12	Initial patch version for Linux 2.5.1 kernel.
  75 */
  76
  77/*-------------------------------------------------------------------------*/
  78
  79/* Keep track of which host controller drivers are loaded */
  80unsigned long usb_hcds_loaded;
  81EXPORT_SYMBOL_GPL(usb_hcds_loaded);
  82
  83/* host controllers we manage */
  84DEFINE_IDR (usb_bus_idr);
  85EXPORT_SYMBOL_GPL (usb_bus_idr);
  86
  87/* used when allocating bus numbers */
  88#define USB_MAXBUS		64
  89
  90/* used when updating list of hcds */
  91DEFINE_MUTEX(usb_bus_idr_lock);	/* exported only for usbfs */
  92EXPORT_SYMBOL_GPL (usb_bus_idr_lock);
  93
  94/* used for controlling access to virtual root hubs */
  95static DEFINE_SPINLOCK(hcd_root_hub_lock);
  96
  97/* used when updating an endpoint's URB list */
  98static DEFINE_SPINLOCK(hcd_urb_list_lock);
  99
 100/* used to protect against unlinking URBs after the device is gone */
 101static DEFINE_SPINLOCK(hcd_urb_unlink_lock);
 102
 103/* wait queue for synchronous unlinks */
 104DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue);
 105
 106/*-------------------------------------------------------------------------*/
 107
 108/*
 109 * Sharable chunks of root hub code.
 110 */
 111
 112/*-------------------------------------------------------------------------*/
 113#define KERNEL_REL	bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff))
 114#define KERNEL_VER	bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff))
 115
 116/* usb 3.1 root hub device descriptor */
 117static const u8 usb31_rh_dev_descriptor[18] = {
 118	0x12,       /*  __u8  bLength; */
 119	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 120	0x10, 0x03, /*  __le16 bcdUSB; v3.1 */
 121
 122	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
 123	0x00,	    /*  __u8  bDeviceSubClass; */
 124	0x03,       /*  __u8  bDeviceProtocol; USB 3 hub */
 125	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
 126
 127	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 128	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
 129	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 130
 131	0x03,       /*  __u8  iManufacturer; */
 132	0x02,       /*  __u8  iProduct; */
 133	0x01,       /*  __u8  iSerialNumber; */
 134	0x01        /*  __u8  bNumConfigurations; */
 135};
 136
 137/* usb 3.0 root hub device descriptor */
 138static const u8 usb3_rh_dev_descriptor[18] = {
 139	0x12,       /*  __u8  bLength; */
 140	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 141	0x00, 0x03, /*  __le16 bcdUSB; v3.0 */
 142
 143	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
 144	0x00,	    /*  __u8  bDeviceSubClass; */
 145	0x03,       /*  __u8  bDeviceProtocol; USB 3.0 hub */
 146	0x09,       /*  __u8  bMaxPacketSize0; 2^9 = 512 Bytes */
 147
 148	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 149	0x03, 0x00, /*  __le16 idProduct; device 0x0003 */
 150	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 151
 152	0x03,       /*  __u8  iManufacturer; */
 153	0x02,       /*  __u8  iProduct; */
 154	0x01,       /*  __u8  iSerialNumber; */
 155	0x01        /*  __u8  bNumConfigurations; */
 156};
 157
 158/* usb 2.5 (wireless USB 1.0) root hub device descriptor */
 159static const u8 usb25_rh_dev_descriptor[18] = {
 160	0x12,       /*  __u8  bLength; */
 161	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 162	0x50, 0x02, /*  __le16 bcdUSB; v2.5 */
 163
 164	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
 165	0x00,	    /*  __u8  bDeviceSubClass; */
 166	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
 167	0xFF,       /*  __u8  bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */
 168
 169	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 170	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
 171	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 172
 173	0x03,       /*  __u8  iManufacturer; */
 174	0x02,       /*  __u8  iProduct; */
 175	0x01,       /*  __u8  iSerialNumber; */
 176	0x01        /*  __u8  bNumConfigurations; */
 177};
 178
 179/* usb 2.0 root hub device descriptor */
 180static const u8 usb2_rh_dev_descriptor[18] = {
 181	0x12,       /*  __u8  bLength; */
 182	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 183	0x00, 0x02, /*  __le16 bcdUSB; v2.0 */
 184
 185	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
 186	0x00,	    /*  __u8  bDeviceSubClass; */
 187	0x00,       /*  __u8  bDeviceProtocol; [ usb 2.0 no TT ] */
 188	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 189
 190	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 191	0x02, 0x00, /*  __le16 idProduct; device 0x0002 */
 192	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 193
 194	0x03,       /*  __u8  iManufacturer; */
 195	0x02,       /*  __u8  iProduct; */
 196	0x01,       /*  __u8  iSerialNumber; */
 197	0x01        /*  __u8  bNumConfigurations; */
 198};
 199
 200/* no usb 2.0 root hub "device qualifier" descriptor: one speed only */
 201
 202/* usb 1.1 root hub device descriptor */
 203static const u8 usb11_rh_dev_descriptor[18] = {
 204	0x12,       /*  __u8  bLength; */
 205	USB_DT_DEVICE, /* __u8 bDescriptorType; Device */
 206	0x10, 0x01, /*  __le16 bcdUSB; v1.1 */
 207
 208	0x09,	    /*  __u8  bDeviceClass; HUB_CLASSCODE */
 209	0x00,	    /*  __u8  bDeviceSubClass; */
 210	0x00,       /*  __u8  bDeviceProtocol; [ low/full speeds only ] */
 211	0x40,       /*  __u8  bMaxPacketSize0; 64 Bytes */
 212
 213	0x6b, 0x1d, /*  __le16 idVendor; Linux Foundation 0x1d6b */
 214	0x01, 0x00, /*  __le16 idProduct; device 0x0001 */
 215	KERNEL_VER, KERNEL_REL, /*  __le16 bcdDevice */
 216
 217	0x03,       /*  __u8  iManufacturer; */
 218	0x02,       /*  __u8  iProduct; */
 219	0x01,       /*  __u8  iSerialNumber; */
 220	0x01        /*  __u8  bNumConfigurations; */
 221};
 222
 223
 224/*-------------------------------------------------------------------------*/
 225
 226/* Configuration descriptors for our root hubs */
 227
 228static const u8 fs_rh_config_descriptor[] = {
 229
 230	/* one configuration */
 231	0x09,       /*  __u8  bLength; */
 232	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 233	0x19, 0x00, /*  __le16 wTotalLength; */
 234	0x01,       /*  __u8  bNumInterfaces; (1) */
 235	0x01,       /*  __u8  bConfigurationValue; */
 236	0x00,       /*  __u8  iConfiguration; */
 237	0xc0,       /*  __u8  bmAttributes;
 238				 Bit 7: must be set,
 239				     6: Self-powered,
 240				     5: Remote wakeup,
 241				     4..0: resvd */
 242	0x00,       /*  __u8  MaxPower; */
 243
 244	/* USB 1.1:
 245	 * USB 2.0, single TT organization (mandatory):
 246	 *	one interface, protocol 0
 247	 *
 248	 * USB 2.0, multiple TT organization (optional):
 249	 *	two interfaces, protocols 1 (like single TT)
 250	 *	and 2 (multiple TT mode) ... config is
 251	 *	sometimes settable
 252	 *	NOT IMPLEMENTED
 253	 */
 254
 255	/* one interface */
 256	0x09,       /*  __u8  if_bLength; */
 257	USB_DT_INTERFACE,  /* __u8 if_bDescriptorType; Interface */
 258	0x00,       /*  __u8  if_bInterfaceNumber; */
 259	0x00,       /*  __u8  if_bAlternateSetting; */
 260	0x01,       /*  __u8  if_bNumEndpoints; */
 261	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 262	0x00,       /*  __u8  if_bInterfaceSubClass; */
 263	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 264	0x00,       /*  __u8  if_iInterface; */
 265
 266	/* one endpoint (status change endpoint) */
 267	0x07,       /*  __u8  ep_bLength; */
 268	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 269	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 270	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 271	0x02, 0x00, /*  __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */
 272	0xff        /*  __u8  ep_bInterval; (255ms -- usb 2.0 spec) */
 273};
 274
 275static const u8 hs_rh_config_descriptor[] = {
 276
 277	/* one configuration */
 278	0x09,       /*  __u8  bLength; */
 279	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 280	0x19, 0x00, /*  __le16 wTotalLength; */
 281	0x01,       /*  __u8  bNumInterfaces; (1) */
 282	0x01,       /*  __u8  bConfigurationValue; */
 283	0x00,       /*  __u8  iConfiguration; */
 284	0xc0,       /*  __u8  bmAttributes;
 285				 Bit 7: must be set,
 286				     6: Self-powered,
 287				     5: Remote wakeup,
 288				     4..0: resvd */
 289	0x00,       /*  __u8  MaxPower; */
 290
 291	/* USB 1.1:
 292	 * USB 2.0, single TT organization (mandatory):
 293	 *	one interface, protocol 0
 294	 *
 295	 * USB 2.0, multiple TT organization (optional):
 296	 *	two interfaces, protocols 1 (like single TT)
 297	 *	and 2 (multiple TT mode) ... config is
 298	 *	sometimes settable
 299	 *	NOT IMPLEMENTED
 300	 */
 301
 302	/* one interface */
 303	0x09,       /*  __u8  if_bLength; */
 304	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
 305	0x00,       /*  __u8  if_bInterfaceNumber; */
 306	0x00,       /*  __u8  if_bAlternateSetting; */
 307	0x01,       /*  __u8  if_bNumEndpoints; */
 308	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 309	0x00,       /*  __u8  if_bInterfaceSubClass; */
 310	0x00,       /*  __u8  if_bInterfaceProtocol; [usb1.1 or single tt] */
 311	0x00,       /*  __u8  if_iInterface; */
 312
 313	/* one endpoint (status change endpoint) */
 314	0x07,       /*  __u8  ep_bLength; */
 315	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 316	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 317	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 318		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 319		     * see hub.c:hub_configure() for details. */
 320	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 321	0x0c        /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 322};
 323
 324static const u8 ss_rh_config_descriptor[] = {
 325	/* one configuration */
 326	0x09,       /*  __u8  bLength; */
 327	USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */
 328	0x1f, 0x00, /*  __le16 wTotalLength; */
 329	0x01,       /*  __u8  bNumInterfaces; (1) */
 330	0x01,       /*  __u8  bConfigurationValue; */
 331	0x00,       /*  __u8  iConfiguration; */
 332	0xc0,       /*  __u8  bmAttributes;
 333				 Bit 7: must be set,
 334				     6: Self-powered,
 335				     5: Remote wakeup,
 336				     4..0: resvd */
 337	0x00,       /*  __u8  MaxPower; */
 338
 339	/* one interface */
 340	0x09,       /*  __u8  if_bLength; */
 341	USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */
 342	0x00,       /*  __u8  if_bInterfaceNumber; */
 343	0x00,       /*  __u8  if_bAlternateSetting; */
 344	0x01,       /*  __u8  if_bNumEndpoints; */
 345	0x09,       /*  __u8  if_bInterfaceClass; HUB_CLASSCODE */
 346	0x00,       /*  __u8  if_bInterfaceSubClass; */
 347	0x00,       /*  __u8  if_bInterfaceProtocol; */
 348	0x00,       /*  __u8  if_iInterface; */
 349
 350	/* one endpoint (status change endpoint) */
 351	0x07,       /*  __u8  ep_bLength; */
 352	USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */
 353	0x81,       /*  __u8  ep_bEndpointAddress; IN Endpoint 1 */
 354	0x03,       /*  __u8  ep_bmAttributes; Interrupt */
 355		    /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8)
 356		     * see hub.c:hub_configure() for details. */
 357	(USB_MAXCHILDREN + 1 + 7) / 8, 0x00,
 358	0x0c,       /*  __u8  ep_bInterval; (256ms -- usb 2.0 spec) */
 359
 360	/* one SuperSpeed endpoint companion descriptor */
 361	0x06,        /* __u8 ss_bLength */
 362	USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */
 363		     /* Companion */
 364	0x00,        /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */
 365	0x00,        /* __u8 ss_bmAttributes; 1 packet per service interval */
 366	0x02, 0x00   /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */
 367};
 368
 369/* authorized_default behaviour:
 370 * -1 is authorized for all devices except wireless (old behaviour)
 371 * 0 is unauthorized for all devices
 372 * 1 is authorized for all devices
 373 * 2 is authorized for internal devices
 374 */
 375#define USB_AUTHORIZE_WIRED	-1
 376#define USB_AUTHORIZE_NONE	0
 377#define USB_AUTHORIZE_ALL	1
 378#define USB_AUTHORIZE_INTERNAL	2
 379
 380static int authorized_default = USB_AUTHORIZE_WIRED;
 381module_param(authorized_default, int, S_IRUGO|S_IWUSR);
 382MODULE_PARM_DESC(authorized_default,
 383		"Default USB device authorization: 0 is not authorized, 1 is "
 384		"authorized, 2 is authorized for internal devices, -1 is "
 385		"authorized except for wireless USB (default, old behaviour)");
 386/*-------------------------------------------------------------------------*/
 387
 388/**
 389 * ascii2desc() - Helper routine for producing UTF-16LE string descriptors
 390 * @s: Null-terminated ASCII (actually ISO-8859-1) string
 391 * @buf: Buffer for USB string descriptor (header + UTF-16LE)
 392 * @len: Length (in bytes; may be odd) of descriptor buffer.
 393 *
 394 * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len,
 395 * whichever is less.
 396 *
 397 * Note:
 398 * USB String descriptors can contain at most 126 characters; input
 399 * strings longer than that are truncated.
 400 */
 401static unsigned
 402ascii2desc(char const *s, u8 *buf, unsigned len)
 403{
 404	unsigned n, t = 2 + 2*strlen(s);
 405
 406	if (t > 254)
 407		t = 254;	/* Longest possible UTF string descriptor */
 408	if (len > t)
 409		len = t;
 410
 411	t += USB_DT_STRING << 8;	/* Now t is first 16 bits to store */
 412
 413	n = len;
 414	while (n--) {
 415		*buf++ = t;
 416		if (!n--)
 417			break;
 418		*buf++ = t >> 8;
 419		t = (unsigned char)*s++;
 420	}
 421	return len;
 422}
 423
 424/**
 425 * rh_string() - provides string descriptors for root hub
 426 * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor)
 427 * @hcd: the host controller for this root hub
 428 * @data: buffer for output packet
 429 * @len: length of the provided buffer
 430 *
 431 * Produces either a manufacturer, product or serial number string for the
 432 * virtual root hub device.
 433 *
 434 * Return: The number of bytes filled in: the length of the descriptor or
 435 * of the provided buffer, whichever is less.
 436 */
 437static unsigned
 438rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len)
 439{
 440	char buf[100];
 441	char const *s;
 442	static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04};
 443
 444	/* language ids */
 445	switch (id) {
 446	case 0:
 447		/* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */
 448		/* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */
 449		if (len > 4)
 450			len = 4;
 451		memcpy(data, langids, len);
 452		return len;
 453	case 1:
 454		/* Serial number */
 455		s = hcd->self.bus_name;
 456		break;
 457	case 2:
 458		/* Product name */
 459		s = hcd->product_desc;
 460		break;
 461	case 3:
 462		/* Manufacturer */
 463		snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname,
 464			init_utsname()->release, hcd->driver->description);
 465		s = buf;
 466		break;
 467	default:
 468		/* Can't happen; caller guarantees it */
 469		return 0;
 470	}
 471
 472	return ascii2desc(s, data, len);
 473}
 474
 475
 476/* Root hub control transfers execute synchronously */
 477static int rh_call_control (struct usb_hcd *hcd, struct urb *urb)
 478{
 479	struct usb_ctrlrequest *cmd;
 480	u16		typeReq, wValue, wIndex, wLength;
 481	u8		*ubuf = urb->transfer_buffer;
 482	unsigned	len = 0;
 483	int		status;
 484	u8		patch_wakeup = 0;
 485	u8		patch_protocol = 0;
 486	u16		tbuf_size;
 487	u8		*tbuf = NULL;
 488	const u8	*bufp;
 489
 490	might_sleep();
 491
 492	spin_lock_irq(&hcd_root_hub_lock);
 493	status = usb_hcd_link_urb_to_ep(hcd, urb);
 494	spin_unlock_irq(&hcd_root_hub_lock);
 495	if (status)
 496		return status;
 497	urb->hcpriv = hcd;	/* Indicate it's queued */
 498
 499	cmd = (struct usb_ctrlrequest *) urb->setup_packet;
 500	typeReq  = (cmd->bRequestType << 8) | cmd->bRequest;
 501	wValue   = le16_to_cpu (cmd->wValue);
 502	wIndex   = le16_to_cpu (cmd->wIndex);
 503	wLength  = le16_to_cpu (cmd->wLength);
 504
 505	if (wLength > urb->transfer_buffer_length)
 506		goto error;
 507
 508	/*
 509	 * tbuf should be at least as big as the
 510	 * USB hub descriptor.
 511	 */
 512	tbuf_size =  max_t(u16, sizeof(struct usb_hub_descriptor), wLength);
 513	tbuf = kzalloc(tbuf_size, GFP_KERNEL);
 514	if (!tbuf) {
 515		status = -ENOMEM;
 516		goto err_alloc;
 517	}
 518
 519	bufp = tbuf;
 520
 521
 522	urb->actual_length = 0;
 523	switch (typeReq) {
 524
 525	/* DEVICE REQUESTS */
 526
 527	/* The root hub's remote wakeup enable bit is implemented using
 528	 * driver model wakeup flags.  If this system supports wakeup
 529	 * through USB, userspace may change the default "allow wakeup"
 530	 * policy through sysfs or these calls.
 531	 *
 532	 * Most root hubs support wakeup from downstream devices, for
 533	 * runtime power management (disabling USB clocks and reducing
 534	 * VBUS power usage).  However, not all of them do so; silicon,
 535	 * board, and BIOS bugs here are not uncommon, so these can't
 536	 * be treated quite like external hubs.
 537	 *
 538	 * Likewise, not all root hubs will pass wakeup events upstream,
 539	 * to wake up the whole system.  So don't assume root hub and
 540	 * controller capabilities are identical.
 541	 */
 542
 543	case DeviceRequest | USB_REQ_GET_STATUS:
 544		tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev)
 545					<< USB_DEVICE_REMOTE_WAKEUP)
 546				| (1 << USB_DEVICE_SELF_POWERED);
 547		tbuf[1] = 0;
 548		len = 2;
 549		break;
 550	case DeviceOutRequest | USB_REQ_CLEAR_FEATURE:
 551		if (wValue == USB_DEVICE_REMOTE_WAKEUP)
 552			device_set_wakeup_enable(&hcd->self.root_hub->dev, 0);
 553		else
 554			goto error;
 555		break;
 556	case DeviceOutRequest | USB_REQ_SET_FEATURE:
 557		if (device_can_wakeup(&hcd->self.root_hub->dev)
 558				&& wValue == USB_DEVICE_REMOTE_WAKEUP)
 559			device_set_wakeup_enable(&hcd->self.root_hub->dev, 1);
 560		else
 561			goto error;
 562		break;
 563	case DeviceRequest | USB_REQ_GET_CONFIGURATION:
 564		tbuf[0] = 1;
 565		len = 1;
 566			/* FALLTHROUGH */
 567	case DeviceOutRequest | USB_REQ_SET_CONFIGURATION:
 568		break;
 569	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 570		switch (wValue & 0xff00) {
 571		case USB_DT_DEVICE << 8:
 572			switch (hcd->speed) {
 573			case HCD_USB32:
 574			case HCD_USB31:
 575				bufp = usb31_rh_dev_descriptor;
 576				break;
 577			case HCD_USB3:
 578				bufp = usb3_rh_dev_descriptor;
 579				break;
 580			case HCD_USB25:
 581				bufp = usb25_rh_dev_descriptor;
 582				break;
 583			case HCD_USB2:
 584				bufp = usb2_rh_dev_descriptor;
 585				break;
 586			case HCD_USB11:
 587				bufp = usb11_rh_dev_descriptor;
 588				break;
 589			default:
 590				goto error;
 591			}
 592			len = 18;
 593			if (hcd->has_tt)
 594				patch_protocol = 1;
 595			break;
 596		case USB_DT_CONFIG << 8:
 597			switch (hcd->speed) {
 598			case HCD_USB32:
 599			case HCD_USB31:
 600			case HCD_USB3:
 601				bufp = ss_rh_config_descriptor;
 602				len = sizeof ss_rh_config_descriptor;
 603				break;
 604			case HCD_USB25:
 605			case HCD_USB2:
 606				bufp = hs_rh_config_descriptor;
 607				len = sizeof hs_rh_config_descriptor;
 608				break;
 609			case HCD_USB11:
 610				bufp = fs_rh_config_descriptor;
 611				len = sizeof fs_rh_config_descriptor;
 612				break;
 613			default:
 614				goto error;
 615			}
 616			if (device_can_wakeup(&hcd->self.root_hub->dev))
 617				patch_wakeup = 1;
 618			break;
 619		case USB_DT_STRING << 8:
 620			if ((wValue & 0xff) < 4)
 621				urb->actual_length = rh_string(wValue & 0xff,
 622						hcd, ubuf, wLength);
 623			else /* unsupported IDs --> "protocol stall" */
 624				goto error;
 625			break;
 626		case USB_DT_BOS << 8:
 627			goto nongeneric;
 628		default:
 629			goto error;
 630		}
 631		break;
 632	case DeviceRequest | USB_REQ_GET_INTERFACE:
 633		tbuf[0] = 0;
 634		len = 1;
 635			/* FALLTHROUGH */
 636	case DeviceOutRequest | USB_REQ_SET_INTERFACE:
 637		break;
 638	case DeviceOutRequest | USB_REQ_SET_ADDRESS:
 639		/* wValue == urb->dev->devaddr */
 640		dev_dbg (hcd->self.controller, "root hub device address %d\n",
 641			wValue);
 642		break;
 643
 644	/* INTERFACE REQUESTS (no defined feature/status flags) */
 645
 646	/* ENDPOINT REQUESTS */
 647
 648	case EndpointRequest | USB_REQ_GET_STATUS:
 649		/* ENDPOINT_HALT flag */
 650		tbuf[0] = 0;
 651		tbuf[1] = 0;
 652		len = 2;
 653			/* FALLTHROUGH */
 654	case EndpointOutRequest | USB_REQ_CLEAR_FEATURE:
 655	case EndpointOutRequest | USB_REQ_SET_FEATURE:
 656		dev_dbg (hcd->self.controller, "no endpoint features yet\n");
 657		break;
 658
 659	/* CLASS REQUESTS (and errors) */
 660
 661	default:
 662nongeneric:
 663		/* non-generic request */
 664		switch (typeReq) {
 665		case GetHubStatus:
 666			len = 4;
 667			break;
 668		case GetPortStatus:
 669			if (wValue == HUB_PORT_STATUS)
 670				len = 4;
 671			else
 672				/* other port status types return 8 bytes */
 673				len = 8;
 674			break;
 675		case GetHubDescriptor:
 676			len = sizeof (struct usb_hub_descriptor);
 677			break;
 678		case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
 679			/* len is returned by hub_control */
 680			break;
 681		}
 682		status = hcd->driver->hub_control (hcd,
 683			typeReq, wValue, wIndex,
 684			tbuf, wLength);
 685
 686		if (typeReq == GetHubDescriptor)
 687			usb_hub_adjust_deviceremovable(hcd->self.root_hub,
 688				(struct usb_hub_descriptor *)tbuf);
 689		break;
 690error:
 691		/* "protocol stall" on error */
 692		status = -EPIPE;
 693	}
 694
 695	if (status < 0) {
 696		len = 0;
 697		if (status != -EPIPE) {
 698			dev_dbg (hcd->self.controller,
 699				"CTRL: TypeReq=0x%x val=0x%x "
 700				"idx=0x%x len=%d ==> %d\n",
 701				typeReq, wValue, wIndex,
 702				wLength, status);
 703		}
 704	} else if (status > 0) {
 705		/* hub_control may return the length of data copied. */
 706		len = status;
 707		status = 0;
 708	}
 709	if (len) {
 710		if (urb->transfer_buffer_length < len)
 711			len = urb->transfer_buffer_length;
 712		urb->actual_length = len;
 713		/* always USB_DIR_IN, toward host */
 714		memcpy (ubuf, bufp, len);
 715
 716		/* report whether RH hardware supports remote wakeup */
 717		if (patch_wakeup &&
 718				len > offsetof (struct usb_config_descriptor,
 719						bmAttributes))
 720			((struct usb_config_descriptor *)ubuf)->bmAttributes
 721				|= USB_CONFIG_ATT_WAKEUP;
 722
 723		/* report whether RH hardware has an integrated TT */
 724		if (patch_protocol &&
 725				len > offsetof(struct usb_device_descriptor,
 726						bDeviceProtocol))
 727			((struct usb_device_descriptor *) ubuf)->
 728				bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT;
 729	}
 730
 731	kfree(tbuf);
 732 err_alloc:
 733
 734	/* any errors get returned through the urb completion */
 735	spin_lock_irq(&hcd_root_hub_lock);
 736	usb_hcd_unlink_urb_from_ep(hcd, urb);
 737	usb_hcd_giveback_urb(hcd, urb, status);
 738	spin_unlock_irq(&hcd_root_hub_lock);
 739	return 0;
 740}
 741
 742/*-------------------------------------------------------------------------*/
 743
 744/*
 745 * Root Hub interrupt transfers are polled using a timer if the
 746 * driver requests it; otherwise the driver is responsible for
 747 * calling usb_hcd_poll_rh_status() when an event occurs.
 748 *
 749 * Completions are called in_interrupt(), but they may or may not
 750 * be in_irq().
 751 */
 752void usb_hcd_poll_rh_status(struct usb_hcd *hcd)
 753{
 754	struct urb	*urb;
 755	int		length;
 756	unsigned long	flags;
 757	char		buffer[6];	/* Any root hubs with > 31 ports? */
 758
 759	if (unlikely(!hcd->rh_pollable))
 760		return;
 761	if (!hcd->uses_new_polling && !hcd->status_urb)
 762		return;
 763
 764	length = hcd->driver->hub_status_data(hcd, buffer);
 765	if (length > 0) {
 766
 767		/* try to complete the status urb */
 768		spin_lock_irqsave(&hcd_root_hub_lock, flags);
 769		urb = hcd->status_urb;
 770		if (urb) {
 771			clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 772			hcd->status_urb = NULL;
 773			urb->actual_length = length;
 774			memcpy(urb->transfer_buffer, buffer, length);
 775
 776			usb_hcd_unlink_urb_from_ep(hcd, urb);
 777			usb_hcd_giveback_urb(hcd, urb, 0);
 778		} else {
 779			length = 0;
 780			set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
 781		}
 782		spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 783	}
 784
 785	/* The USB 2.0 spec says 256 ms.  This is close enough and won't
 786	 * exceed that limit if HZ is 100. The math is more clunky than
 787	 * maybe expected, this is to make sure that all timers for USB devices
 788	 * fire at the same time to give the CPU a break in between */
 789	if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
 790			(length == 0 && hcd->status_urb != NULL))
 791		mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 792}
 793EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status);
 794
 795/* timer callback */
 796static void rh_timer_func (struct timer_list *t)
 797{
 798	struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer);
 799
 800	usb_hcd_poll_rh_status(_hcd);
 801}
 802
 803/*-------------------------------------------------------------------------*/
 804
 805static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb)
 806{
 807	int		retval;
 808	unsigned long	flags;
 809	unsigned	len = 1 + (urb->dev->maxchild / 8);
 810
 811	spin_lock_irqsave (&hcd_root_hub_lock, flags);
 812	if (hcd->status_urb || urb->transfer_buffer_length < len) {
 813		dev_dbg (hcd->self.controller, "not queuing rh status urb\n");
 814		retval = -EINVAL;
 815		goto done;
 816	}
 817
 818	retval = usb_hcd_link_urb_to_ep(hcd, urb);
 819	if (retval)
 820		goto done;
 821
 822	hcd->status_urb = urb;
 823	urb->hcpriv = hcd;	/* indicate it's queued */
 824	if (!hcd->uses_new_polling)
 825		mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
 826
 827	/* If a status change has already occurred, report it ASAP */
 828	else if (HCD_POLL_PENDING(hcd))
 829		mod_timer(&hcd->rh_timer, jiffies);
 830	retval = 0;
 831 done:
 832	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
 833	return retval;
 834}
 835
 836static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb)
 837{
 838	if (usb_endpoint_xfer_int(&urb->ep->desc))
 839		return rh_queue_status (hcd, urb);
 840	if (usb_endpoint_xfer_control(&urb->ep->desc))
 841		return rh_call_control (hcd, urb);
 842	return -EINVAL;
 843}
 844
 845/*-------------------------------------------------------------------------*/
 846
 847/* Unlinks of root-hub control URBs are legal, but they don't do anything
 848 * since these URBs always execute synchronously.
 849 */
 850static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 851{
 852	unsigned long	flags;
 853	int		rc;
 854
 855	spin_lock_irqsave(&hcd_root_hub_lock, flags);
 856	rc = usb_hcd_check_unlink_urb(hcd, urb, status);
 857	if (rc)
 858		goto done;
 859
 860	if (usb_endpoint_num(&urb->ep->desc) == 0) {	/* Control URB */
 861		;	/* Do nothing */
 862
 863	} else {				/* Status URB */
 864		if (!hcd->uses_new_polling)
 865			del_timer (&hcd->rh_timer);
 866		if (urb == hcd->status_urb) {
 867			hcd->status_urb = NULL;
 868			usb_hcd_unlink_urb_from_ep(hcd, urb);
 869			usb_hcd_giveback_urb(hcd, urb, status);
 870		}
 871	}
 872 done:
 873	spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
 874	return rc;
 875}
 876
 877
 878/*-------------------------------------------------------------------------*/
 879
 880/**
 881 * usb_bus_init - shared initialization code
 882 * @bus: the bus structure being initialized
 883 *
 884 * This code is used to initialize a usb_bus structure, memory for which is
 885 * separately managed.
 886 */
 887static void usb_bus_init (struct usb_bus *bus)
 888{
 889	memset (&bus->devmap, 0, sizeof(struct usb_devmap));
 890
 891	bus->devnum_next = 1;
 892
 893	bus->root_hub = NULL;
 894	bus->busnum = -1;
 895	bus->bandwidth_allocated = 0;
 896	bus->bandwidth_int_reqs  = 0;
 897	bus->bandwidth_isoc_reqs = 0;
 898	mutex_init(&bus->devnum_next_mutex);
 899}
 900
 901/*-------------------------------------------------------------------------*/
 902
 903/**
 904 * usb_register_bus - registers the USB host controller with the usb core
 905 * @bus: pointer to the bus to register
 906 * Context: !in_interrupt()
 907 *
 908 * Assigns a bus number, and links the controller into usbcore data
 909 * structures so that it can be seen by scanning the bus list.
 910 *
 911 * Return: 0 if successful. A negative error code otherwise.
 912 */
 913static int usb_register_bus(struct usb_bus *bus)
 914{
 915	int result = -E2BIG;
 916	int busnum;
 917
 918	mutex_lock(&usb_bus_idr_lock);
 919	busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL);
 920	if (busnum < 0) {
 921		pr_err("%s: failed to get bus number\n", usbcore_name);
 922		goto error_find_busnum;
 923	}
 924	bus->busnum = busnum;
 925	mutex_unlock(&usb_bus_idr_lock);
 926
 927	usb_notify_add_bus(bus);
 928
 929	dev_info (bus->controller, "new USB bus registered, assigned bus "
 930		  "number %d\n", bus->busnum);
 931	return 0;
 932
 933error_find_busnum:
 934	mutex_unlock(&usb_bus_idr_lock);
 935	return result;
 936}
 937
 938/**
 939 * usb_deregister_bus - deregisters the USB host controller
 940 * @bus: pointer to the bus to deregister
 941 * Context: !in_interrupt()
 942 *
 943 * Recycles the bus number, and unlinks the controller from usbcore data
 944 * structures so that it won't be seen by scanning the bus list.
 945 */
 946static void usb_deregister_bus (struct usb_bus *bus)
 947{
 948	dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum);
 949
 950	/*
 951	 * NOTE: make sure that all the devices are removed by the
 952	 * controller code, as well as having it call this when cleaning
 953	 * itself up
 954	 */
 955	mutex_lock(&usb_bus_idr_lock);
 956	idr_remove(&usb_bus_idr, bus->busnum);
 957	mutex_unlock(&usb_bus_idr_lock);
 958
 959	usb_notify_remove_bus(bus);
 960}
 961
 962/**
 963 * register_root_hub - called by usb_add_hcd() to register a root hub
 964 * @hcd: host controller for this root hub
 965 *
 966 * This function registers the root hub with the USB subsystem.  It sets up
 967 * the device properly in the device tree and then calls usb_new_device()
 968 * to register the usb device.  It also assigns the root hub's USB address
 969 * (always 1).
 970 *
 971 * Return: 0 if successful. A negative error code otherwise.
 972 */
 973static int register_root_hub(struct usb_hcd *hcd)
 974{
 975	struct device *parent_dev = hcd->self.controller;
 976	struct usb_device *usb_dev = hcd->self.root_hub;
 977	const int devnum = 1;
 978	int retval;
 979
 980	usb_dev->devnum = devnum;
 981	usb_dev->bus->devnum_next = devnum + 1;
 982	set_bit (devnum, usb_dev->bus->devmap.devicemap);
 983	usb_set_device_state(usb_dev, USB_STATE_ADDRESS);
 984
 985	mutex_lock(&usb_bus_idr_lock);
 986
 987	usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64);
 988	retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE);
 989	if (retval != sizeof usb_dev->descriptor) {
 990		mutex_unlock(&usb_bus_idr_lock);
 991		dev_dbg (parent_dev, "can't read %s device descriptor %d\n",
 992				dev_name(&usb_dev->dev), retval);
 993		return (retval < 0) ? retval : -EMSGSIZE;
 994	}
 995
 996	if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) {
 997		retval = usb_get_bos_descriptor(usb_dev);
 998		if (!retval) {
 999			usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev);
1000		} else if (usb_dev->speed >= USB_SPEED_SUPER) {
1001			mutex_unlock(&usb_bus_idr_lock);
1002			dev_dbg(parent_dev, "can't read %s bos descriptor %d\n",
1003					dev_name(&usb_dev->dev), retval);
1004			return retval;
1005		}
1006	}
1007
1008	retval = usb_new_device (usb_dev);
1009	if (retval) {
1010		dev_err (parent_dev, "can't register root hub for %s, %d\n",
1011				dev_name(&usb_dev->dev), retval);
1012	} else {
1013		spin_lock_irq (&hcd_root_hub_lock);
1014		hcd->rh_registered = 1;
1015		spin_unlock_irq (&hcd_root_hub_lock);
1016
1017		/* Did the HC die before the root hub was registered? */
1018		if (HCD_DEAD(hcd))
1019			usb_hc_died (hcd);	/* This time clean up */
1020	}
1021	mutex_unlock(&usb_bus_idr_lock);
1022
1023	return retval;
1024}
1025
1026/*
1027 * usb_hcd_start_port_resume - a root-hub port is sending a resume signal
1028 * @bus: the bus which the root hub belongs to
1029 * @portnum: the port which is being resumed
1030 *
1031 * HCDs should call this function when they know that a resume signal is
1032 * being sent to a root-hub port.  The root hub will be prevented from
1033 * going into autosuspend until usb_hcd_end_port_resume() is called.
1034 *
1035 * The bus's private lock must be held by the caller.
1036 */
1037void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum)
1038{
1039	unsigned bit = 1 << portnum;
1040
1041	if (!(bus->resuming_ports & bit)) {
1042		bus->resuming_ports |= bit;
1043		pm_runtime_get_noresume(&bus->root_hub->dev);
1044	}
1045}
1046EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume);
1047
1048/*
1049 * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal
1050 * @bus: the bus which the root hub belongs to
1051 * @portnum: the port which is being resumed
1052 *
1053 * HCDs should call this function when they know that a resume signal has
1054 * stopped being sent to a root-hub port.  The root hub will be allowed to
1055 * autosuspend again.
1056 *
1057 * The bus's private lock must be held by the caller.
1058 */
1059void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum)
1060{
1061	unsigned bit = 1 << portnum;
1062
1063	if (bus->resuming_ports & bit) {
1064		bus->resuming_ports &= ~bit;
1065		pm_runtime_put_noidle(&bus->root_hub->dev);
1066	}
1067}
1068EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume);
1069
1070/*-------------------------------------------------------------------------*/
1071
1072/**
1073 * usb_calc_bus_time - approximate periodic transaction time in nanoseconds
1074 * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH}
1075 * @is_input: true iff the transaction sends data to the host
1076 * @isoc: true for isochronous transactions, false for interrupt ones
1077 * @bytecount: how many bytes in the transaction.
1078 *
1079 * Return: Approximate bus time in nanoseconds for a periodic transaction.
1080 *
1081 * Note:
1082 * See USB 2.0 spec section 5.11.3; only periodic transfers need to be
1083 * scheduled in software, this function is only used for such scheduling.
1084 */
1085long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount)
1086{
1087	unsigned long	tmp;
1088
1089	switch (speed) {
1090	case USB_SPEED_LOW: 	/* INTR only */
1091		if (is_input) {
1092			tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L;
1093			return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1094		} else {
1095			tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L;
1096			return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp;
1097		}
1098	case USB_SPEED_FULL:	/* ISOC or INTR */
1099		if (isoc) {
1100			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1101			return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp;
1102		} else {
1103			tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L;
1104			return 9107L + BW_HOST_DELAY + tmp;
1105		}
1106	case USB_SPEED_HIGH:	/* ISOC or INTR */
1107		/* FIXME adjust for input vs output */
1108		if (isoc)
1109			tmp = HS_NSECS_ISO (bytecount);
1110		else
1111			tmp = HS_NSECS (bytecount);
1112		return tmp;
1113	default:
1114		pr_debug ("%s: bogus device speed!\n", usbcore_name);
1115		return -1;
1116	}
1117}
1118EXPORT_SYMBOL_GPL(usb_calc_bus_time);
1119
1120
1121/*-------------------------------------------------------------------------*/
1122
1123/*
1124 * Generic HC operations.
1125 */
1126
1127/*-------------------------------------------------------------------------*/
1128
1129/**
1130 * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue
1131 * @hcd: host controller to which @urb was submitted
1132 * @urb: URB being submitted
1133 *
1134 * Host controller drivers should call this routine in their enqueue()
1135 * method.  The HCD's private spinlock must be held and interrupts must
1136 * be disabled.  The actions carried out here are required for URB
1137 * submission, as well as for endpoint shutdown and for usb_kill_urb.
1138 *
1139 * Return: 0 for no error, otherwise a negative error code (in which case
1140 * the enqueue() method must fail).  If no error occurs but enqueue() fails
1141 * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing
1142 * the private spinlock and returning.
1143 */
1144int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb)
1145{
1146	int		rc = 0;
1147
1148	spin_lock(&hcd_urb_list_lock);
1149
1150	/* Check that the URB isn't being killed */
1151	if (unlikely(atomic_read(&urb->reject))) {
1152		rc = -EPERM;
1153		goto done;
1154	}
1155
1156	if (unlikely(!urb->ep->enabled)) {
1157		rc = -ENOENT;
1158		goto done;
1159	}
1160
1161	if (unlikely(!urb->dev->can_submit)) {
1162		rc = -EHOSTUNREACH;
1163		goto done;
1164	}
1165
1166	/*
1167	 * Check the host controller's state and add the URB to the
1168	 * endpoint's queue.
1169	 */
1170	if (HCD_RH_RUNNING(hcd)) {
1171		urb->unlinked = 0;
1172		list_add_tail(&urb->urb_list, &urb->ep->urb_list);
1173	} else {
1174		rc = -ESHUTDOWN;
1175		goto done;
1176	}
1177 done:
1178	spin_unlock(&hcd_urb_list_lock);
1179	return rc;
1180}
1181EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep);
1182
1183/**
1184 * usb_hcd_check_unlink_urb - check whether an URB may be unlinked
1185 * @hcd: host controller to which @urb was submitted
1186 * @urb: URB being checked for unlinkability
1187 * @status: error code to store in @urb if the unlink succeeds
1188 *
1189 * Host controller drivers should call this routine in their dequeue()
1190 * method.  The HCD's private spinlock must be held and interrupts must
1191 * be disabled.  The actions carried out here are required for making
1192 * sure than an unlink is valid.
1193 *
1194 * Return: 0 for no error, otherwise a negative error code (in which case
1195 * the dequeue() method must fail).  The possible error codes are:
1196 *
1197 *	-EIDRM: @urb was not submitted or has already completed.
1198 *		The completion function may not have been called yet.
1199 *
1200 *	-EBUSY: @urb has already been unlinked.
1201 */
1202int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb,
1203		int status)
1204{
1205	struct list_head	*tmp;
1206
1207	/* insist the urb is still queued */
1208	list_for_each(tmp, &urb->ep->urb_list) {
1209		if (tmp == &urb->urb_list)
1210			break;
1211	}
1212	if (tmp != &urb->urb_list)
1213		return -EIDRM;
1214
1215	/* Any status except -EINPROGRESS means something already started to
1216	 * unlink this URB from the hardware.  So there's no more work to do.
1217	 */
1218	if (urb->unlinked)
1219		return -EBUSY;
1220	urb->unlinked = status;
1221	return 0;
1222}
1223EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb);
1224
1225/**
1226 * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue
1227 * @hcd: host controller to which @urb was submitted
1228 * @urb: URB being unlinked
1229 *
1230 * Host controller drivers should call this routine before calling
1231 * usb_hcd_giveback_urb().  The HCD's private spinlock must be held and
1232 * interrupts must be disabled.  The actions carried out here are required
1233 * for URB completion.
1234 */
1235void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb)
1236{
1237	/* clear all state linking urb to this dev (and hcd) */
1238	spin_lock(&hcd_urb_list_lock);
1239	list_del_init(&urb->urb_list);
1240	spin_unlock(&hcd_urb_list_lock);
1241}
1242EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep);
1243
1244/*
1245 * Some usb host controllers can only perform dma using a small SRAM area.
1246 * The usb core itself is however optimized for host controllers that can dma
1247 * using regular system memory - like pci devices doing bus mastering.
1248 *
1249 * To support host controllers with limited dma capabilities we provide dma
1250 * bounce buffers. This feature can be enabled by initializing
1251 * hcd->localmem_pool using usb_hcd_setup_local_mem().
1252 *
1253 * The initialized hcd->localmem_pool then tells the usb code to allocate all
1254 * data for dma using the genalloc API.
1255 *
1256 * So, to summarize...
1257 *
1258 * - We need "local" memory, canonical example being
1259 *   a small SRAM on a discrete controller being the
1260 *   only memory that the controller can read ...
1261 *   (a) "normal" kernel memory is no good, and
1262 *   (b) there's not enough to share
1263 *
1264 * - So we use that, even though the primary requirement
1265 *   is that the memory be "local" (hence addressable
1266 *   by that device), not "coherent".
1267 *
1268 */
1269
1270static int hcd_alloc_coherent(struct usb_bus *bus,
1271			      gfp_t mem_flags, dma_addr_t *dma_handle,
1272			      void **vaddr_handle, size_t size,
1273			      enum dma_data_direction dir)
1274{
1275	unsigned char *vaddr;
1276
1277	if (*vaddr_handle == NULL) {
1278		WARN_ON_ONCE(1);
1279		return -EFAULT;
1280	}
1281
1282	vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr),
1283				 mem_flags, dma_handle);
1284	if (!vaddr)
1285		return -ENOMEM;
1286
1287	/*
1288	 * Store the virtual address of the buffer at the end
1289	 * of the allocated dma buffer. The size of the buffer
1290	 * may be uneven so use unaligned functions instead
1291	 * of just rounding up. It makes sense to optimize for
1292	 * memory footprint over access speed since the amount
1293	 * of memory available for dma may be limited.
1294	 */
1295	put_unaligned((unsigned long)*vaddr_handle,
1296		      (unsigned long *)(vaddr + size));
1297
1298	if (dir == DMA_TO_DEVICE)
1299		memcpy(vaddr, *vaddr_handle, size);
1300
1301	*vaddr_handle = vaddr;
1302	return 0;
1303}
1304
1305static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle,
1306			      void **vaddr_handle, size_t size,
1307			      enum dma_data_direction dir)
1308{
1309	unsigned char *vaddr = *vaddr_handle;
1310
1311	vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size));
1312
1313	if (dir == DMA_FROM_DEVICE)
1314		memcpy(vaddr, *vaddr_handle, size);
1315
1316	hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle);
1317
1318	*vaddr_handle = vaddr;
1319	*dma_handle = 0;
1320}
1321
1322void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb)
1323{
1324	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1325	    (urb->transfer_flags & URB_SETUP_MAP_SINGLE))
1326		dma_unmap_single(hcd->self.sysdev,
1327				urb->setup_dma,
1328				sizeof(struct usb_ctrlrequest),
1329				DMA_TO_DEVICE);
1330	else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL)
1331		hcd_free_coherent(urb->dev->bus,
1332				&urb->setup_dma,
1333				(void **) &urb->setup_packet,
1334				sizeof(struct usb_ctrlrequest),
1335				DMA_TO_DEVICE);
1336
1337	/* Make it safe to call this routine more than once */
1338	urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL);
1339}
1340EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma);
1341
1342static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1343{
1344	if (hcd->driver->unmap_urb_for_dma)
1345		hcd->driver->unmap_urb_for_dma(hcd, urb);
1346	else
1347		usb_hcd_unmap_urb_for_dma(hcd, urb);
1348}
1349
1350void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1351{
1352	enum dma_data_direction dir;
1353
1354	usb_hcd_unmap_urb_setup_for_dma(hcd, urb);
1355
1356	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1357	if (IS_ENABLED(CONFIG_HAS_DMA) &&
1358	    (urb->transfer_flags & URB_DMA_MAP_SG))
1359		dma_unmap_sg(hcd->self.sysdev,
1360				urb->sg,
1361				urb->num_sgs,
1362				dir);
1363	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1364		 (urb->transfer_flags & URB_DMA_MAP_PAGE))
1365		dma_unmap_page(hcd->self.sysdev,
1366				urb->transfer_dma,
1367				urb->transfer_buffer_length,
1368				dir);
1369	else if (IS_ENABLED(CONFIG_HAS_DMA) &&
1370		 (urb->transfer_flags & URB_DMA_MAP_SINGLE))
1371		dma_unmap_single(hcd->self.sysdev,
1372				urb->transfer_dma,
1373				urb->transfer_buffer_length,
1374				dir);
1375	else if (urb->transfer_flags & URB_MAP_LOCAL)
1376		hcd_free_coherent(urb->dev->bus,
1377				&urb->transfer_dma,
1378				&urb->transfer_buffer,
1379				urb->transfer_buffer_length,
1380				dir);
1381
1382	/* Make it safe to call this routine more than once */
1383	urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE |
1384			URB_DMA_MAP_SINGLE | URB_MAP_LOCAL);
1385}
1386EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma);
1387
1388static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1389			   gfp_t mem_flags)
1390{
1391	if (hcd->driver->map_urb_for_dma)
1392		return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags);
1393	else
1394		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
1395}
1396
1397int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
1398			    gfp_t mem_flags)
1399{
1400	enum dma_data_direction dir;
1401	int ret = 0;
1402
1403	/* Map the URB's buffers for DMA access.
1404	 * Lower level HCD code should use *_dma exclusively,
1405	 * unless it uses pio or talks to another transport,
1406	 * or uses the provided scatter gather list for bulk.
1407	 */
1408
1409	if (usb_endpoint_xfer_control(&urb->ep->desc)) {
1410		if (hcd->self.uses_pio_for_control)
1411			return ret;
1412		if (hcd_uses_dma(hcd)) {
1413			if (is_vmalloc_addr(urb->setup_packet)) {
1414				WARN_ONCE(1, "setup packet is not dma capable\n");
1415				return -EAGAIN;
1416			} else if (object_is_on_stack(urb->setup_packet)) {
 
 
 
 
 
 
 
1417				WARN_ONCE(1, "setup packet is on stack\n");
1418				return -EAGAIN;
1419			}
1420
1421			urb->setup_dma = dma_map_single(
1422					hcd->self.sysdev,
1423					urb->setup_packet,
1424					sizeof(struct usb_ctrlrequest),
1425					DMA_TO_DEVICE);
1426			if (dma_mapping_error(hcd->self.sysdev,
1427						urb->setup_dma))
1428				return -EAGAIN;
1429			urb->transfer_flags |= URB_SETUP_MAP_SINGLE;
1430		} else if (hcd->localmem_pool) {
1431			ret = hcd_alloc_coherent(
1432					urb->dev->bus, mem_flags,
1433					&urb->setup_dma,
1434					(void **)&urb->setup_packet,
1435					sizeof(struct usb_ctrlrequest),
1436					DMA_TO_DEVICE);
1437			if (ret)
1438				return ret;
1439			urb->transfer_flags |= URB_SETUP_MAP_LOCAL;
1440		}
1441	}
1442
1443	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1444	if (urb->transfer_buffer_length != 0
1445	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
1446		if (hcd_uses_dma(hcd)) {
 
 
 
 
 
 
 
 
 
1447			if (urb->num_sgs) {
1448				int n;
1449
1450				/* We don't support sg for isoc transfers ! */
1451				if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
1452					WARN_ON(1);
1453					return -EINVAL;
1454				}
1455
1456				n = dma_map_sg(
1457						hcd->self.sysdev,
1458						urb->sg,
1459						urb->num_sgs,
1460						dir);
1461				if (n <= 0)
1462					ret = -EAGAIN;
1463				else
1464					urb->transfer_flags |= URB_DMA_MAP_SG;
1465				urb->num_mapped_sgs = n;
1466				if (n != urb->num_sgs)
1467					urb->transfer_flags |=
1468							URB_DMA_SG_COMBINED;
1469			} else if (urb->sg) {
1470				struct scatterlist *sg = urb->sg;
1471				urb->transfer_dma = dma_map_page(
1472						hcd->self.sysdev,
1473						sg_page(sg),
1474						sg->offset,
1475						urb->transfer_buffer_length,
1476						dir);
1477				if (dma_mapping_error(hcd->self.sysdev,
1478						urb->transfer_dma))
1479					ret = -EAGAIN;
1480				else
1481					urb->transfer_flags |= URB_DMA_MAP_PAGE;
1482			} else if (is_vmalloc_addr(urb->transfer_buffer)) {
1483				WARN_ONCE(1, "transfer buffer not dma capable\n");
1484				ret = -EAGAIN;
1485			} else if (object_is_on_stack(urb->transfer_buffer)) {
1486				WARN_ONCE(1, "transfer buffer is on stack\n");
1487				ret = -EAGAIN;
1488			} else {
1489				urb->transfer_dma = dma_map_single(
1490						hcd->self.sysdev,
1491						urb->transfer_buffer,
1492						urb->transfer_buffer_length,
1493						dir);
1494				if (dma_mapping_error(hcd->self.sysdev,
1495						urb->transfer_dma))
1496					ret = -EAGAIN;
1497				else
1498					urb->transfer_flags |= URB_DMA_MAP_SINGLE;
1499			}
1500		} else if (hcd->localmem_pool) {
1501			ret = hcd_alloc_coherent(
1502					urb->dev->bus, mem_flags,
1503					&urb->transfer_dma,
1504					&urb->transfer_buffer,
1505					urb->transfer_buffer_length,
1506					dir);
1507			if (ret == 0)
1508				urb->transfer_flags |= URB_MAP_LOCAL;
1509		}
1510		if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE |
1511				URB_SETUP_MAP_LOCAL)))
1512			usb_hcd_unmap_urb_for_dma(hcd, urb);
1513	}
1514	return ret;
1515}
1516EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma);
1517
1518/*-------------------------------------------------------------------------*/
1519
1520/* may be called in any context with a valid urb->dev usecount
1521 * caller surrenders "ownership" of urb
1522 * expects usb_submit_urb() to have sanity checked and conditioned all
1523 * inputs in the urb
1524 */
1525int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags)
1526{
1527	int			status;
1528	struct usb_hcd		*hcd = bus_to_hcd(urb->dev->bus);
1529
1530	/* increment urb's reference count as part of giving it to the HCD
1531	 * (which will control it).  HCD guarantees that it either returns
1532	 * an error or calls giveback(), but not both.
1533	 */
1534	usb_get_urb(urb);
1535	atomic_inc(&urb->use_count);
1536	atomic_inc(&urb->dev->urbnum);
1537	usbmon_urb_submit(&hcd->self, urb);
1538
1539	/* NOTE requirements on root-hub callers (usbfs and the hub
1540	 * driver, for now):  URBs' urb->transfer_buffer must be
1541	 * valid and usb_buffer_{sync,unmap}() not be needed, since
1542	 * they could clobber root hub response data.  Also, control
1543	 * URBs must be submitted in process context with interrupts
1544	 * enabled.
1545	 */
1546
1547	if (is_root_hub(urb->dev)) {
1548		status = rh_urb_enqueue(hcd, urb);
1549	} else {
1550		status = map_urb_for_dma(hcd, urb, mem_flags);
1551		if (likely(status == 0)) {
1552			status = hcd->driver->urb_enqueue(hcd, urb, mem_flags);
1553			if (unlikely(status))
1554				unmap_urb_for_dma(hcd, urb);
1555		}
1556	}
1557
1558	if (unlikely(status)) {
1559		usbmon_urb_submit_error(&hcd->self, urb, status);
1560		urb->hcpriv = NULL;
1561		INIT_LIST_HEAD(&urb->urb_list);
1562		atomic_dec(&urb->use_count);
1563		atomic_dec(&urb->dev->urbnum);
1564		if (atomic_read(&urb->reject))
1565			wake_up(&usb_kill_urb_queue);
1566		usb_put_urb(urb);
1567	}
1568	return status;
1569}
1570
1571/*-------------------------------------------------------------------------*/
1572
1573/* this makes the hcd giveback() the urb more quickly, by kicking it
1574 * off hardware queues (which may take a while) and returning it as
1575 * soon as practical.  we've already set up the urb's return status,
1576 * but we can't know if the callback completed already.
1577 */
1578static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status)
1579{
1580	int		value;
1581
1582	if (is_root_hub(urb->dev))
1583		value = usb_rh_urb_dequeue(hcd, urb, status);
1584	else {
1585
1586		/* The only reason an HCD might fail this call is if
1587		 * it has not yet fully queued the urb to begin with.
1588		 * Such failures should be harmless. */
1589		value = hcd->driver->urb_dequeue(hcd, urb, status);
1590	}
1591	return value;
1592}
1593
1594/*
1595 * called in any context
1596 *
1597 * caller guarantees urb won't be recycled till both unlink()
1598 * and the urb's completion function return
1599 */
1600int usb_hcd_unlink_urb (struct urb *urb, int status)
1601{
1602	struct usb_hcd		*hcd;
1603	struct usb_device	*udev = urb->dev;
1604	int			retval = -EIDRM;
1605	unsigned long		flags;
1606
1607	/* Prevent the device and bus from going away while
1608	 * the unlink is carried out.  If they are already gone
1609	 * then urb->use_count must be 0, since disconnected
1610	 * devices can't have any active URBs.
1611	 */
1612	spin_lock_irqsave(&hcd_urb_unlink_lock, flags);
1613	if (atomic_read(&urb->use_count) > 0) {
1614		retval = 0;
1615		usb_get_dev(udev);
1616	}
1617	spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags);
1618	if (retval == 0) {
1619		hcd = bus_to_hcd(urb->dev->bus);
1620		retval = unlink1(hcd, urb, status);
1621		if (retval == 0)
1622			retval = -EINPROGRESS;
1623		else if (retval != -EIDRM && retval != -EBUSY)
1624			dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n",
1625					urb, retval);
1626		usb_put_dev(udev);
1627	}
1628	return retval;
1629}
1630
1631/*-------------------------------------------------------------------------*/
1632
1633static void __usb_hcd_giveback_urb(struct urb *urb)
1634{
1635	struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
1636	struct usb_anchor *anchor = urb->anchor;
1637	int status = urb->unlinked;
1638
1639	urb->hcpriv = NULL;
1640	if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) &&
1641	    urb->actual_length < urb->transfer_buffer_length &&
1642	    !status))
1643		status = -EREMOTEIO;
1644
1645	unmap_urb_for_dma(hcd, urb);
1646	usbmon_urb_complete(&hcd->self, urb, status);
1647	usb_anchor_suspend_wakeups(anchor);
1648	usb_unanchor_urb(urb);
1649	if (likely(status == 0))
1650		usb_led_activity(USB_LED_EVENT_HOST);
1651
1652	/* pass ownership to the completion handler */
1653	urb->status = status;
 
1654	urb->complete(urb);
 
1655
1656	usb_anchor_resume_wakeups(anchor);
1657	atomic_dec(&urb->use_count);
1658	if (unlikely(atomic_read(&urb->reject)))
1659		wake_up(&usb_kill_urb_queue);
1660	usb_put_urb(urb);
1661}
1662
1663static void usb_giveback_urb_bh(unsigned long param)
1664{
1665	struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param;
1666	struct list_head local_list;
1667
1668	spin_lock_irq(&bh->lock);
1669	bh->running = true;
1670 restart:
1671	list_replace_init(&bh->head, &local_list);
1672	spin_unlock_irq(&bh->lock);
1673
1674	while (!list_empty(&local_list)) {
1675		struct urb *urb;
1676
1677		urb = list_entry(local_list.next, struct urb, urb_list);
1678		list_del_init(&urb->urb_list);
1679		bh->completing_ep = urb->ep;
1680		__usb_hcd_giveback_urb(urb);
1681		bh->completing_ep = NULL;
1682	}
1683
1684	/* check if there are new URBs to giveback */
1685	spin_lock_irq(&bh->lock);
1686	if (!list_empty(&bh->head))
1687		goto restart;
1688	bh->running = false;
1689	spin_unlock_irq(&bh->lock);
1690}
1691
1692/**
1693 * usb_hcd_giveback_urb - return URB from HCD to device driver
1694 * @hcd: host controller returning the URB
1695 * @urb: urb being returned to the USB device driver.
1696 * @status: completion status code for the URB.
1697 * Context: in_interrupt()
1698 *
1699 * This hands the URB from HCD to its USB device driver, using its
1700 * completion function.  The HCD has freed all per-urb resources
1701 * (and is done using urb->hcpriv).  It also released all HCD locks;
1702 * the device driver won't cause problems if it frees, modifies,
1703 * or resubmits this URB.
1704 *
1705 * If @urb was unlinked, the value of @status will be overridden by
1706 * @urb->unlinked.  Erroneous short transfers are detected in case
1707 * the HCD hasn't checked for them.
1708 */
1709void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status)
1710{
1711	struct giveback_urb_bh *bh;
1712	bool running, high_prio_bh;
1713
1714	/* pass status to tasklet via unlinked */
1715	if (likely(!urb->unlinked))
1716		urb->unlinked = status;
1717
1718	if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) {
1719		__usb_hcd_giveback_urb(urb);
1720		return;
1721	}
1722
1723	if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) {
1724		bh = &hcd->high_prio_bh;
1725		high_prio_bh = true;
1726	} else {
1727		bh = &hcd->low_prio_bh;
1728		high_prio_bh = false;
1729	}
1730
1731	spin_lock(&bh->lock);
1732	list_add_tail(&urb->urb_list, &bh->head);
1733	running = bh->running;
1734	spin_unlock(&bh->lock);
1735
1736	if (running)
1737		;
1738	else if (high_prio_bh)
1739		tasklet_hi_schedule(&bh->bh);
1740	else
1741		tasklet_schedule(&bh->bh);
1742}
1743EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb);
1744
1745/*-------------------------------------------------------------------------*/
1746
1747/* Cancel all URBs pending on this endpoint and wait for the endpoint's
1748 * queue to drain completely.  The caller must first insure that no more
1749 * URBs can be submitted for this endpoint.
1750 */
1751void usb_hcd_flush_endpoint(struct usb_device *udev,
1752		struct usb_host_endpoint *ep)
1753{
1754	struct usb_hcd		*hcd;
1755	struct urb		*urb;
1756
1757	if (!ep)
1758		return;
1759	might_sleep();
1760	hcd = bus_to_hcd(udev->bus);
1761
1762	/* No more submits can occur */
1763	spin_lock_irq(&hcd_urb_list_lock);
1764rescan:
1765	list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) {
1766		int	is_in;
1767
1768		if (urb->unlinked)
1769			continue;
1770		usb_get_urb (urb);
1771		is_in = usb_urb_dir_in(urb);
1772		spin_unlock(&hcd_urb_list_lock);
1773
1774		/* kick hcd */
1775		unlink1(hcd, urb, -ESHUTDOWN);
1776		dev_dbg (hcd->self.controller,
1777			"shutdown urb %pK ep%d%s-%s\n",
1778			urb, usb_endpoint_num(&ep->desc),
1779			is_in ? "in" : "out",
1780			usb_ep_type_string(usb_endpoint_type(&ep->desc)));
1781		usb_put_urb (urb);
1782
1783		/* list contents may have changed */
1784		spin_lock(&hcd_urb_list_lock);
1785		goto rescan;
1786	}
1787	spin_unlock_irq(&hcd_urb_list_lock);
1788
1789	/* Wait until the endpoint queue is completely empty */
1790	while (!list_empty (&ep->urb_list)) {
1791		spin_lock_irq(&hcd_urb_list_lock);
1792
1793		/* The list may have changed while we acquired the spinlock */
1794		urb = NULL;
1795		if (!list_empty (&ep->urb_list)) {
1796			urb = list_entry (ep->urb_list.prev, struct urb,
1797					urb_list);
1798			usb_get_urb (urb);
1799		}
1800		spin_unlock_irq(&hcd_urb_list_lock);
1801
1802		if (urb) {
1803			usb_kill_urb (urb);
1804			usb_put_urb (urb);
1805		}
1806	}
1807}
1808
1809/**
1810 * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds
1811 *				the bus bandwidth
1812 * @udev: target &usb_device
1813 * @new_config: new configuration to install
1814 * @cur_alt: the current alternate interface setting
1815 * @new_alt: alternate interface setting that is being installed
1816 *
1817 * To change configurations, pass in the new configuration in new_config,
1818 * and pass NULL for cur_alt and new_alt.
1819 *
1820 * To reset a device's configuration (put the device in the ADDRESSED state),
1821 * pass in NULL for new_config, cur_alt, and new_alt.
1822 *
1823 * To change alternate interface settings, pass in NULL for new_config,
1824 * pass in the current alternate interface setting in cur_alt,
1825 * and pass in the new alternate interface setting in new_alt.
1826 *
1827 * Return: An error if the requested bandwidth change exceeds the
1828 * bus bandwidth or host controller internal resources.
1829 */
1830int usb_hcd_alloc_bandwidth(struct usb_device *udev,
1831		struct usb_host_config *new_config,
1832		struct usb_host_interface *cur_alt,
1833		struct usb_host_interface *new_alt)
1834{
1835	int num_intfs, i, j;
1836	struct usb_host_interface *alt = NULL;
1837	int ret = 0;
1838	struct usb_hcd *hcd;
1839	struct usb_host_endpoint *ep;
1840
1841	hcd = bus_to_hcd(udev->bus);
1842	if (!hcd->driver->check_bandwidth)
1843		return 0;
1844
1845	/* Configuration is being removed - set configuration 0 */
1846	if (!new_config && !cur_alt) {
1847		for (i = 1; i < 16; ++i) {
1848			ep = udev->ep_out[i];
1849			if (ep)
1850				hcd->driver->drop_endpoint(hcd, udev, ep);
1851			ep = udev->ep_in[i];
1852			if (ep)
1853				hcd->driver->drop_endpoint(hcd, udev, ep);
1854		}
1855		hcd->driver->check_bandwidth(hcd, udev);
1856		return 0;
1857	}
1858	/* Check if the HCD says there's enough bandwidth.  Enable all endpoints
1859	 * each interface's alt setting 0 and ask the HCD to check the bandwidth
1860	 * of the bus.  There will always be bandwidth for endpoint 0, so it's
1861	 * ok to exclude it.
1862	 */
1863	if (new_config) {
1864		num_intfs = new_config->desc.bNumInterfaces;
1865		/* Remove endpoints (except endpoint 0, which is always on the
1866		 * schedule) from the old config from the schedule
1867		 */
1868		for (i = 1; i < 16; ++i) {
1869			ep = udev->ep_out[i];
1870			if (ep) {
1871				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1872				if (ret < 0)
1873					goto reset;
1874			}
1875			ep = udev->ep_in[i];
1876			if (ep) {
1877				ret = hcd->driver->drop_endpoint(hcd, udev, ep);
1878				if (ret < 0)
1879					goto reset;
1880			}
1881		}
1882		for (i = 0; i < num_intfs; ++i) {
1883			struct usb_host_interface *first_alt;
1884			int iface_num;
1885
1886			first_alt = &new_config->intf_cache[i]->altsetting[0];
1887			iface_num = first_alt->desc.bInterfaceNumber;
1888			/* Set up endpoints for alternate interface setting 0 */
1889			alt = usb_find_alt_setting(new_config, iface_num, 0);
1890			if (!alt)
1891				/* No alt setting 0? Pick the first setting. */
1892				alt = first_alt;
1893
1894			for (j = 0; j < alt->desc.bNumEndpoints; j++) {
1895				ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
1896				if (ret < 0)
1897					goto reset;
1898			}
1899		}
1900	}
1901	if (cur_alt && new_alt) {
1902		struct usb_interface *iface = usb_ifnum_to_if(udev,
1903				cur_alt->desc.bInterfaceNumber);
1904
1905		if (!iface)
1906			return -EINVAL;
1907		if (iface->resetting_device) {
1908			/*
1909			 * The USB core just reset the device, so the xHCI host
1910			 * and the device will think alt setting 0 is installed.
1911			 * However, the USB core will pass in the alternate
1912			 * setting installed before the reset as cur_alt.  Dig
1913			 * out the alternate setting 0 structure, or the first
1914			 * alternate setting if a broken device doesn't have alt
1915			 * setting 0.
1916			 */
1917			cur_alt = usb_altnum_to_altsetting(iface, 0);
1918			if (!cur_alt)
1919				cur_alt = &iface->altsetting[0];
1920		}
1921
1922		/* Drop all the endpoints in the current alt setting */
1923		for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
1924			ret = hcd->driver->drop_endpoint(hcd, udev,
1925					&cur_alt->endpoint[i]);
1926			if (ret < 0)
1927				goto reset;
1928		}
1929		/* Add all the endpoints in the new alt setting */
1930		for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
1931			ret = hcd->driver->add_endpoint(hcd, udev,
1932					&new_alt->endpoint[i]);
1933			if (ret < 0)
1934				goto reset;
1935		}
1936	}
1937	ret = hcd->driver->check_bandwidth(hcd, udev);
1938reset:
1939	if (ret < 0)
1940		hcd->driver->reset_bandwidth(hcd, udev);
1941	return ret;
1942}
1943
1944/* Disables the endpoint: synchronizes with the hcd to make sure all
1945 * endpoint state is gone from hardware.  usb_hcd_flush_endpoint() must
1946 * have been called previously.  Use for set_configuration, set_interface,
1947 * driver removal, physical disconnect.
1948 *
1949 * example:  a qh stored in ep->hcpriv, holding state related to endpoint
1950 * type, maxpacket size, toggle, halt status, and scheduling.
1951 */
1952void usb_hcd_disable_endpoint(struct usb_device *udev,
1953		struct usb_host_endpoint *ep)
1954{
1955	struct usb_hcd		*hcd;
1956
1957	might_sleep();
1958	hcd = bus_to_hcd(udev->bus);
1959	if (hcd->driver->endpoint_disable)
1960		hcd->driver->endpoint_disable(hcd, ep);
1961}
1962
1963/**
1964 * usb_hcd_reset_endpoint - reset host endpoint state
1965 * @udev: USB device.
1966 * @ep:   the endpoint to reset.
1967 *
1968 * Resets any host endpoint state such as the toggle bit, sequence
1969 * number and current window.
1970 */
1971void usb_hcd_reset_endpoint(struct usb_device *udev,
1972			    struct usb_host_endpoint *ep)
1973{
1974	struct usb_hcd *hcd = bus_to_hcd(udev->bus);
1975
1976	if (hcd->driver->endpoint_reset)
1977		hcd->driver->endpoint_reset(hcd, ep);
1978	else {
1979		int epnum = usb_endpoint_num(&ep->desc);
1980		int is_out = usb_endpoint_dir_out(&ep->desc);
1981		int is_control = usb_endpoint_xfer_control(&ep->desc);
1982
1983		usb_settoggle(udev, epnum, is_out, 0);
1984		if (is_control)
1985			usb_settoggle(udev, epnum, !is_out, 0);
1986	}
1987}
1988
1989/**
1990 * usb_alloc_streams - allocate bulk endpoint stream IDs.
1991 * @interface:		alternate setting that includes all endpoints.
1992 * @eps:		array of endpoints that need streams.
1993 * @num_eps:		number of endpoints in the array.
1994 * @num_streams:	number of streams to allocate.
1995 * @mem_flags:		flags hcd should use to allocate memory.
1996 *
1997 * Sets up a group of bulk endpoints to have @num_streams stream IDs available.
1998 * Drivers may queue multiple transfers to different stream IDs, which may
1999 * complete in a different order than they were queued.
2000 *
2001 * Return: On success, the number of allocated streams. On failure, a negative
2002 * error code.
2003 */
2004int usb_alloc_streams(struct usb_interface *interface,
2005		struct usb_host_endpoint **eps, unsigned int num_eps,
2006		unsigned int num_streams, gfp_t mem_flags)
2007{
2008	struct usb_hcd *hcd;
2009	struct usb_device *dev;
2010	int i, ret;
2011
2012	dev = interface_to_usbdev(interface);
2013	hcd = bus_to_hcd(dev->bus);
2014	if (!hcd->driver->alloc_streams || !hcd->driver->free_streams)
2015		return -EINVAL;
2016	if (dev->speed < USB_SPEED_SUPER)
2017		return -EINVAL;
2018	if (dev->state < USB_STATE_CONFIGURED)
2019		return -ENODEV;
2020
2021	for (i = 0; i < num_eps; i++) {
2022		/* Streams only apply to bulk endpoints. */
2023		if (!usb_endpoint_xfer_bulk(&eps[i]->desc))
2024			return -EINVAL;
2025		/* Re-alloc is not allowed */
2026		if (eps[i]->streams)
2027			return -EINVAL;
2028	}
2029
2030	ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps,
2031			num_streams, mem_flags);
2032	if (ret < 0)
2033		return ret;
2034
2035	for (i = 0; i < num_eps; i++)
2036		eps[i]->streams = ret;
2037
2038	return ret;
2039}
2040EXPORT_SYMBOL_GPL(usb_alloc_streams);
2041
2042/**
2043 * usb_free_streams - free bulk endpoint stream IDs.
2044 * @interface:	alternate setting that includes all endpoints.
2045 * @eps:	array of endpoints to remove streams from.
2046 * @num_eps:	number of endpoints in the array.
2047 * @mem_flags:	flags hcd should use to allocate memory.
2048 *
2049 * Reverts a group of bulk endpoints back to not using stream IDs.
2050 * Can fail if we are given bad arguments, or HCD is broken.
2051 *
2052 * Return: 0 on success. On failure, a negative error code.
2053 */
2054int usb_free_streams(struct usb_interface *interface,
2055		struct usb_host_endpoint **eps, unsigned int num_eps,
2056		gfp_t mem_flags)
2057{
2058	struct usb_hcd *hcd;
2059	struct usb_device *dev;
2060	int i, ret;
2061
2062	dev = interface_to_usbdev(interface);
2063	hcd = bus_to_hcd(dev->bus);
2064	if (dev->speed < USB_SPEED_SUPER)
2065		return -EINVAL;
2066
2067	/* Double-free is not allowed */
2068	for (i = 0; i < num_eps; i++)
2069		if (!eps[i] || !eps[i]->streams)
2070			return -EINVAL;
2071
2072	ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags);
2073	if (ret < 0)
2074		return ret;
2075
2076	for (i = 0; i < num_eps; i++)
2077		eps[i]->streams = 0;
2078
2079	return ret;
2080}
2081EXPORT_SYMBOL_GPL(usb_free_streams);
2082
2083/* Protect against drivers that try to unlink URBs after the device
2084 * is gone, by waiting until all unlinks for @udev are finished.
2085 * Since we don't currently track URBs by device, simply wait until
2086 * nothing is running in the locked region of usb_hcd_unlink_urb().
2087 */
2088void usb_hcd_synchronize_unlinks(struct usb_device *udev)
2089{
2090	spin_lock_irq(&hcd_urb_unlink_lock);
2091	spin_unlock_irq(&hcd_urb_unlink_lock);
2092}
2093
2094/*-------------------------------------------------------------------------*/
2095
2096/* called in any context */
2097int usb_hcd_get_frame_number (struct usb_device *udev)
2098{
2099	struct usb_hcd	*hcd = bus_to_hcd(udev->bus);
2100
2101	if (!HCD_RH_RUNNING(hcd))
2102		return -ESHUTDOWN;
2103	return hcd->driver->get_frame_number (hcd);
2104}
2105
2106/*-------------------------------------------------------------------------*/
2107
2108#ifdef	CONFIG_PM
2109
2110int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg)
2111{
2112	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2113	int		status;
2114	int		old_state = hcd->state;
2115
2116	dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n",
2117			(PMSG_IS_AUTO(msg) ? "auto-" : ""),
2118			rhdev->do_remote_wakeup);
2119	if (HCD_DEAD(hcd)) {
2120		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend");
2121		return 0;
2122	}
2123
2124	if (!hcd->driver->bus_suspend) {
2125		status = -ENOENT;
2126	} else {
2127		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2128		hcd->state = HC_STATE_QUIESCING;
2129		status = hcd->driver->bus_suspend(hcd);
2130	}
2131	if (status == 0) {
2132		usb_set_device_state(rhdev, USB_STATE_SUSPENDED);
2133		hcd->state = HC_STATE_SUSPENDED;
2134
2135		if (!PMSG_IS_AUTO(msg))
2136			usb_phy_roothub_suspend(hcd->self.sysdev,
2137						hcd->phy_roothub);
2138
2139		/* Did we race with a root-hub wakeup event? */
2140		if (rhdev->do_remote_wakeup) {
2141			char	buffer[6];
2142
2143			status = hcd->driver->hub_status_data(hcd, buffer);
2144			if (status != 0) {
2145				dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n");
2146				hcd_bus_resume(rhdev, PMSG_AUTO_RESUME);
2147				status = -EBUSY;
2148			}
2149		}
2150	} else {
2151		spin_lock_irq(&hcd_root_hub_lock);
2152		if (!HCD_DEAD(hcd)) {
2153			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2154			hcd->state = old_state;
2155		}
2156		spin_unlock_irq(&hcd_root_hub_lock);
2157		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2158				"suspend", status);
2159	}
2160	return status;
2161}
2162
2163int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
2164{
2165	struct usb_hcd	*hcd = bus_to_hcd(rhdev->bus);
2166	int		status;
2167	int		old_state = hcd->state;
2168
2169	dev_dbg(&rhdev->dev, "usb %sresume\n",
2170			(PMSG_IS_AUTO(msg) ? "auto-" : ""));
2171	if (HCD_DEAD(hcd)) {
2172		dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume");
2173		return 0;
2174	}
2175
2176	if (!PMSG_IS_AUTO(msg)) {
2177		status = usb_phy_roothub_resume(hcd->self.sysdev,
2178						hcd->phy_roothub);
2179		if (status)
2180			return status;
2181	}
2182
2183	if (!hcd->driver->bus_resume)
2184		return -ENOENT;
2185	if (HCD_RH_RUNNING(hcd))
2186		return 0;
2187
2188	hcd->state = HC_STATE_RESUMING;
2189	status = hcd->driver->bus_resume(hcd);
2190	clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2191	if (status == 0)
2192		status = usb_phy_roothub_calibrate(hcd->phy_roothub);
2193
2194	if (status == 0) {
2195		struct usb_device *udev;
2196		int port1;
2197
2198		spin_lock_irq(&hcd_root_hub_lock);
2199		if (!HCD_DEAD(hcd)) {
2200			usb_set_device_state(rhdev, rhdev->actconfig
2201					? USB_STATE_CONFIGURED
2202					: USB_STATE_ADDRESS);
2203			set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2204			hcd->state = HC_STATE_RUNNING;
2205		}
2206		spin_unlock_irq(&hcd_root_hub_lock);
2207
2208		/*
2209		 * Check whether any of the enabled ports on the root hub are
2210		 * unsuspended.  If they are then a TRSMRCY delay is needed
2211		 * (this is what the USB-2 spec calls a "global resume").
2212		 * Otherwise we can skip the delay.
2213		 */
2214		usb_hub_for_each_child(rhdev, port1, udev) {
2215			if (udev->state != USB_STATE_NOTATTACHED &&
2216					!udev->port_is_suspended) {
2217				usleep_range(10000, 11000);	/* TRSMRCY */
2218				break;
2219			}
2220		}
2221	} else {
2222		hcd->state = old_state;
2223		usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub);
2224		dev_dbg(&rhdev->dev, "bus %s fail, err %d\n",
2225				"resume", status);
2226		if (status != -ESHUTDOWN)
2227			usb_hc_died(hcd);
2228	}
2229	return status;
2230}
2231
2232/* Workqueue routine for root-hub remote wakeup */
2233static void hcd_resume_work(struct work_struct *work)
2234{
2235	struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work);
2236	struct usb_device *udev = hcd->self.root_hub;
2237
2238	usb_remote_wakeup(udev);
2239}
2240
2241/**
2242 * usb_hcd_resume_root_hub - called by HCD to resume its root hub
2243 * @hcd: host controller for this root hub
2244 *
2245 * The USB host controller calls this function when its root hub is
2246 * suspended (with the remote wakeup feature enabled) and a remote
2247 * wakeup request is received.  The routine submits a workqueue request
2248 * to resume the root hub (that is, manage its downstream ports again).
2249 */
2250void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
2251{
2252	unsigned long flags;
2253
2254	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2255	if (hcd->rh_registered) {
2256		pm_wakeup_event(&hcd->self.root_hub->dev, 0);
2257		set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
2258		queue_work(pm_wq, &hcd->wakeup_work);
2259	}
2260	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2261}
2262EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
2263
2264#endif	/* CONFIG_PM */
2265
2266/*-------------------------------------------------------------------------*/
2267
2268#ifdef	CONFIG_USB_OTG
2269
2270/**
2271 * usb_bus_start_enum - start immediate enumeration (for OTG)
2272 * @bus: the bus (must use hcd framework)
2273 * @port_num: 1-based number of port; usually bus->otg_port
2274 * Context: in_interrupt()
2275 *
2276 * Starts enumeration, with an immediate reset followed later by
2277 * hub_wq identifying and possibly configuring the device.
2278 * This is needed by OTG controller drivers, where it helps meet
2279 * HNP protocol timing requirements for starting a port reset.
2280 *
2281 * Return: 0 if successful.
2282 */
2283int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num)
2284{
2285	struct usb_hcd		*hcd;
2286	int			status = -EOPNOTSUPP;
2287
2288	/* NOTE: since HNP can't start by grabbing the bus's address0_sem,
2289	 * boards with root hubs hooked up to internal devices (instead of
2290	 * just the OTG port) may need more attention to resetting...
2291	 */
2292	hcd = bus_to_hcd(bus);
2293	if (port_num && hcd->driver->start_port_reset)
2294		status = hcd->driver->start_port_reset(hcd, port_num);
2295
2296	/* allocate hub_wq shortly after (first) root port reset finishes;
2297	 * it may issue others, until at least 50 msecs have passed.
2298	 */
2299	if (status == 0)
2300		mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10));
2301	return status;
2302}
2303EXPORT_SYMBOL_GPL(usb_bus_start_enum);
2304
2305#endif
2306
2307/*-------------------------------------------------------------------------*/
2308
2309/**
2310 * usb_hcd_irq - hook IRQs to HCD framework (bus glue)
2311 * @irq: the IRQ being raised
2312 * @__hcd: pointer to the HCD whose IRQ is being signaled
2313 *
2314 * If the controller isn't HALTed, calls the driver's irq handler.
2315 * Checks whether the controller is now dead.
2316 *
2317 * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise.
2318 */
2319irqreturn_t usb_hcd_irq (int irq, void *__hcd)
2320{
2321	struct usb_hcd		*hcd = __hcd;
2322	irqreturn_t		rc;
2323
2324	if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd)))
2325		rc = IRQ_NONE;
2326	else if (hcd->driver->irq(hcd) == IRQ_NONE)
2327		rc = IRQ_NONE;
2328	else
2329		rc = IRQ_HANDLED;
2330
2331	return rc;
2332}
2333EXPORT_SYMBOL_GPL(usb_hcd_irq);
2334
2335/*-------------------------------------------------------------------------*/
2336
2337/* Workqueue routine for when the root-hub has died. */
2338static void hcd_died_work(struct work_struct *work)
2339{
2340	struct usb_hcd *hcd = container_of(work, struct usb_hcd, died_work);
2341	static char *env[] = {
2342		"ERROR=DEAD",
2343		NULL
2344	};
2345
2346	/* Notify user space that the host controller has died */
2347	kobject_uevent_env(&hcd->self.root_hub->dev.kobj, KOBJ_OFFLINE, env);
2348}
2349
2350/**
2351 * usb_hc_died - report abnormal shutdown of a host controller (bus glue)
2352 * @hcd: pointer to the HCD representing the controller
2353 *
2354 * This is called by bus glue to report a USB host controller that died
2355 * while operations may still have been pending.  It's called automatically
2356 * by the PCI glue, so only glue for non-PCI busses should need to call it.
2357 *
2358 * Only call this function with the primary HCD.
2359 */
2360void usb_hc_died (struct usb_hcd *hcd)
2361{
2362	unsigned long flags;
2363
2364	dev_err (hcd->self.controller, "HC died; cleaning up\n");
2365
2366	spin_lock_irqsave (&hcd_root_hub_lock, flags);
2367	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2368	set_bit(HCD_FLAG_DEAD, &hcd->flags);
2369	if (hcd->rh_registered) {
2370		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2371
2372		/* make hub_wq clean up old urbs and devices */
2373		usb_set_device_state (hcd->self.root_hub,
2374				USB_STATE_NOTATTACHED);
2375		usb_kick_hub_wq(hcd->self.root_hub);
2376	}
2377	if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) {
2378		hcd = hcd->shared_hcd;
2379		clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2380		set_bit(HCD_FLAG_DEAD, &hcd->flags);
2381		if (hcd->rh_registered) {
2382			clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2383
2384			/* make hub_wq clean up old urbs and devices */
2385			usb_set_device_state(hcd->self.root_hub,
2386					USB_STATE_NOTATTACHED);
2387			usb_kick_hub_wq(hcd->self.root_hub);
2388		}
2389	}
2390
2391	/* Handle the case where this function gets called with a shared HCD */
2392	if (usb_hcd_is_primary_hcd(hcd))
2393		schedule_work(&hcd->died_work);
2394	else
2395		schedule_work(&hcd->primary_hcd->died_work);
2396
2397	spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
2398	/* Make sure that the other roothub is also deallocated. */
2399}
2400EXPORT_SYMBOL_GPL (usb_hc_died);
2401
2402/*-------------------------------------------------------------------------*/
2403
2404static void init_giveback_urb_bh(struct giveback_urb_bh *bh)
2405{
2406
2407	spin_lock_init(&bh->lock);
2408	INIT_LIST_HEAD(&bh->head);
2409	tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh);
2410}
2411
2412struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver,
2413		struct device *sysdev, struct device *dev, const char *bus_name,
2414		struct usb_hcd *primary_hcd)
2415{
2416	struct usb_hcd *hcd;
2417
2418	hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL);
2419	if (!hcd)
2420		return NULL;
2421	if (primary_hcd == NULL) {
2422		hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex),
2423				GFP_KERNEL);
2424		if (!hcd->address0_mutex) {
2425			kfree(hcd);
2426			dev_dbg(dev, "hcd address0 mutex alloc failed\n");
2427			return NULL;
2428		}
2429		mutex_init(hcd->address0_mutex);
2430		hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex),
2431				GFP_KERNEL);
2432		if (!hcd->bandwidth_mutex) {
2433			kfree(hcd->address0_mutex);
2434			kfree(hcd);
2435			dev_dbg(dev, "hcd bandwidth mutex alloc failed\n");
2436			return NULL;
2437		}
2438		mutex_init(hcd->bandwidth_mutex);
2439		dev_set_drvdata(dev, hcd);
2440	} else {
2441		mutex_lock(&usb_port_peer_mutex);
2442		hcd->address0_mutex = primary_hcd->address0_mutex;
2443		hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex;
2444		hcd->primary_hcd = primary_hcd;
2445		primary_hcd->primary_hcd = primary_hcd;
2446		hcd->shared_hcd = primary_hcd;
2447		primary_hcd->shared_hcd = hcd;
2448		mutex_unlock(&usb_port_peer_mutex);
2449	}
2450
2451	kref_init(&hcd->kref);
2452
2453	usb_bus_init(&hcd->self);
2454	hcd->self.controller = dev;
2455	hcd->self.sysdev = sysdev;
2456	hcd->self.bus_name = bus_name;
2457
2458	timer_setup(&hcd->rh_timer, rh_timer_func, 0);
2459#ifdef CONFIG_PM
2460	INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
2461#endif
2462
2463	INIT_WORK(&hcd->died_work, hcd_died_work);
2464
2465	hcd->driver = driver;
2466	hcd->speed = driver->flags & HCD_MASK;
2467	hcd->product_desc = (driver->product_desc) ? driver->product_desc :
2468			"USB Host Controller";
2469	return hcd;
2470}
2471EXPORT_SYMBOL_GPL(__usb_create_hcd);
2472
2473/**
2474 * usb_create_shared_hcd - create and initialize an HCD structure
2475 * @driver: HC driver that will use this hcd
2476 * @dev: device for this HC, stored in hcd->self.controller
2477 * @bus_name: value to store in hcd->self.bus_name
2478 * @primary_hcd: a pointer to the usb_hcd structure that is sharing the
2479 *              PCI device.  Only allocate certain resources for the primary HCD
2480 * Context: !in_interrupt()
2481 *
2482 * Allocate a struct usb_hcd, with extra space at the end for the
2483 * HC driver's private data.  Initialize the generic members of the
2484 * hcd structure.
2485 *
2486 * Return: On success, a pointer to the created and initialized HCD structure.
2487 * On failure (e.g. if memory is unavailable), %NULL.
2488 */
2489struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver,
2490		struct device *dev, const char *bus_name,
2491		struct usb_hcd *primary_hcd)
2492{
2493	return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd);
2494}
2495EXPORT_SYMBOL_GPL(usb_create_shared_hcd);
2496
2497/**
2498 * usb_create_hcd - create and initialize an HCD structure
2499 * @driver: HC driver that will use this hcd
2500 * @dev: device for this HC, stored in hcd->self.controller
2501 * @bus_name: value to store in hcd->self.bus_name
2502 * Context: !in_interrupt()
2503 *
2504 * Allocate a struct usb_hcd, with extra space at the end for the
2505 * HC driver's private data.  Initialize the generic members of the
2506 * hcd structure.
2507 *
2508 * Return: On success, a pointer to the created and initialized HCD
2509 * structure. On failure (e.g. if memory is unavailable), %NULL.
2510 */
2511struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
2512		struct device *dev, const char *bus_name)
2513{
2514	return __usb_create_hcd(driver, dev, dev, bus_name, NULL);
2515}
2516EXPORT_SYMBOL_GPL(usb_create_hcd);
2517
2518/*
2519 * Roothubs that share one PCI device must also share the bandwidth mutex.
2520 * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is
2521 * deallocated.
2522 *
2523 * Make sure to deallocate the bandwidth_mutex only when the last HCD is
2524 * freed.  When hcd_release() is called for either hcd in a peer set,
2525 * invalidate the peer's ->shared_hcd and ->primary_hcd pointers.
2526 */
2527static void hcd_release(struct kref *kref)
2528{
2529	struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref);
2530
2531	mutex_lock(&usb_port_peer_mutex);
2532	if (hcd->shared_hcd) {
2533		struct usb_hcd *peer = hcd->shared_hcd;
2534
2535		peer->shared_hcd = NULL;
2536		peer->primary_hcd = NULL;
2537	} else {
2538		kfree(hcd->address0_mutex);
2539		kfree(hcd->bandwidth_mutex);
2540	}
2541	mutex_unlock(&usb_port_peer_mutex);
2542	kfree(hcd);
2543}
2544
2545struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd)
2546{
2547	if (hcd)
2548		kref_get (&hcd->kref);
2549	return hcd;
2550}
2551EXPORT_SYMBOL_GPL(usb_get_hcd);
2552
2553void usb_put_hcd (struct usb_hcd *hcd)
2554{
2555	if (hcd)
2556		kref_put (&hcd->kref, hcd_release);
2557}
2558EXPORT_SYMBOL_GPL(usb_put_hcd);
2559
2560int usb_hcd_is_primary_hcd(struct usb_hcd *hcd)
2561{
2562	if (!hcd->primary_hcd)
2563		return 1;
2564	return hcd == hcd->primary_hcd;
2565}
2566EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd);
2567
2568int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1)
2569{
2570	if (!hcd->driver->find_raw_port_number)
2571		return port1;
2572
2573	return hcd->driver->find_raw_port_number(hcd, port1);
2574}
2575
2576static int usb_hcd_request_irqs(struct usb_hcd *hcd,
2577		unsigned int irqnum, unsigned long irqflags)
2578{
2579	int retval;
2580
2581	if (hcd->driver->irq) {
2582
2583		snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d",
2584				hcd->driver->description, hcd->self.busnum);
2585		retval = request_irq(irqnum, &usb_hcd_irq, irqflags,
2586				hcd->irq_descr, hcd);
2587		if (retval != 0) {
2588			dev_err(hcd->self.controller,
2589					"request interrupt %d failed\n",
2590					irqnum);
2591			return retval;
2592		}
2593		hcd->irq = irqnum;
2594		dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum,
2595				(hcd->driver->flags & HCD_MEMORY) ?
2596					"io mem" : "io base",
2597					(unsigned long long)hcd->rsrc_start);
2598	} else {
2599		hcd->irq = 0;
2600		if (hcd->rsrc_start)
2601			dev_info(hcd->self.controller, "%s 0x%08llx\n",
2602					(hcd->driver->flags & HCD_MEMORY) ?
2603					"io mem" : "io base",
2604					(unsigned long long)hcd->rsrc_start);
2605	}
2606	return 0;
2607}
2608
2609/*
2610 * Before we free this root hub, flush in-flight peering attempts
2611 * and disable peer lookups
2612 */
2613static void usb_put_invalidate_rhdev(struct usb_hcd *hcd)
2614{
2615	struct usb_device *rhdev;
2616
2617	mutex_lock(&usb_port_peer_mutex);
2618	rhdev = hcd->self.root_hub;
2619	hcd->self.root_hub = NULL;
2620	mutex_unlock(&usb_port_peer_mutex);
2621	usb_put_dev(rhdev);
2622}
2623
2624/**
2625 * usb_add_hcd - finish generic HCD structure initialization and register
2626 * @hcd: the usb_hcd structure to initialize
2627 * @irqnum: Interrupt line to allocate
2628 * @irqflags: Interrupt type flags
2629 *
2630 * Finish the remaining parts of generic HCD initialization: allocate the
2631 * buffers of consistent memory, register the bus, request the IRQ line,
2632 * and call the driver's reset() and start() routines.
2633 */
2634int usb_add_hcd(struct usb_hcd *hcd,
2635		unsigned int irqnum, unsigned long irqflags)
2636{
2637	int retval;
2638	struct usb_device *rhdev;
2639
2640	if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) {
2641		hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev);
2642		if (IS_ERR(hcd->phy_roothub))
2643			return PTR_ERR(hcd->phy_roothub);
2644
2645		retval = usb_phy_roothub_init(hcd->phy_roothub);
2646		if (retval)
2647			return retval;
2648
2649		retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2650						  PHY_MODE_USB_HOST_SS);
2651		if (retval)
2652			retval = usb_phy_roothub_set_mode(hcd->phy_roothub,
2653							  PHY_MODE_USB_HOST);
2654		if (retval)
2655			goto err_usb_phy_roothub_power_on;
2656
2657		retval = usb_phy_roothub_power_on(hcd->phy_roothub);
2658		if (retval)
2659			goto err_usb_phy_roothub_power_on;
2660	}
2661
2662	dev_info(hcd->self.controller, "%s\n", hcd->product_desc);
2663
2664	switch (authorized_default) {
2665	case USB_AUTHORIZE_NONE:
2666		hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE;
2667		break;
2668
2669	case USB_AUTHORIZE_ALL:
2670		hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL;
2671		break;
2672
2673	case USB_AUTHORIZE_INTERNAL:
2674		hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL;
2675		break;
2676
2677	case USB_AUTHORIZE_WIRED:
2678	default:
2679		hcd->dev_policy = hcd->wireless ?
2680			USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL;
2681		break;
2682	}
2683
2684	set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
2685
2686	/* per default all interfaces are authorized */
2687	set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
2688
2689	/* HC is in reset state, but accessible.  Now do the one-time init,
2690	 * bottom up so that hcds can customize the root hubs before hub_wq
2691	 * starts talking to them.  (Note, bus id is assigned early too.)
2692	 */
2693	retval = hcd_buffer_create(hcd);
2694	if (retval != 0) {
2695		dev_dbg(hcd->self.sysdev, "pool alloc failed\n");
2696		goto err_create_buf;
2697	}
2698
2699	retval = usb_register_bus(&hcd->self);
2700	if (retval < 0)
2701		goto err_register_bus;
2702
2703	rhdev = usb_alloc_dev(NULL, &hcd->self, 0);
2704	if (rhdev == NULL) {
2705		dev_err(hcd->self.sysdev, "unable to allocate root hub\n");
2706		retval = -ENOMEM;
2707		goto err_allocate_root_hub;
2708	}
2709	mutex_lock(&usb_port_peer_mutex);
2710	hcd->self.root_hub = rhdev;
2711	mutex_unlock(&usb_port_peer_mutex);
2712
2713	rhdev->rx_lanes = 1;
2714	rhdev->tx_lanes = 1;
2715
2716	switch (hcd->speed) {
2717	case HCD_USB11:
2718		rhdev->speed = USB_SPEED_FULL;
2719		break;
2720	case HCD_USB2:
2721		rhdev->speed = USB_SPEED_HIGH;
2722		break;
2723	case HCD_USB25:
2724		rhdev->speed = USB_SPEED_WIRELESS;
2725		break;
2726	case HCD_USB3:
2727		rhdev->speed = USB_SPEED_SUPER;
2728		break;
2729	case HCD_USB32:
2730		rhdev->rx_lanes = 2;
2731		rhdev->tx_lanes = 2;
2732		/* fall through */
2733	case HCD_USB31:
2734		rhdev->speed = USB_SPEED_SUPER_PLUS;
2735		break;
2736	default:
2737		retval = -EINVAL;
2738		goto err_set_rh_speed;
2739	}
2740
2741	/* wakeup flag init defaults to "everything works" for root hubs,
2742	 * but drivers can override it in reset() if needed, along with
2743	 * recording the overall controller's system wakeup capability.
2744	 */
2745	device_set_wakeup_capable(&rhdev->dev, 1);
2746
2747	/* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is
2748	 * registered.  But since the controller can die at any time,
2749	 * let's initialize the flag before touching the hardware.
2750	 */
2751	set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2752
2753	/* "reset" is misnamed; its role is now one-time init. the controller
2754	 * should already have been reset (and boot firmware kicked off etc).
2755	 */
2756	if (hcd->driver->reset) {
2757		retval = hcd->driver->reset(hcd);
2758		if (retval < 0) {
2759			dev_err(hcd->self.controller, "can't setup: %d\n",
2760					retval);
2761			goto err_hcd_driver_setup;
2762		}
2763	}
2764	hcd->rh_pollable = 1;
2765
2766	retval = usb_phy_roothub_calibrate(hcd->phy_roothub);
2767	if (retval)
2768		goto err_hcd_driver_setup;
2769
2770	/* NOTE: root hub and controller capabilities may not be the same */
2771	if (device_can_wakeup(hcd->self.controller)
2772			&& device_can_wakeup(&hcd->self.root_hub->dev))
2773		dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
2774
2775	/* initialize tasklets */
2776	init_giveback_urb_bh(&hcd->high_prio_bh);
2777	init_giveback_urb_bh(&hcd->low_prio_bh);
2778
2779	/* enable irqs just before we start the controller,
2780	 * if the BIOS provides legacy PCI irqs.
2781	 */
2782	if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
2783		retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
2784		if (retval)
2785			goto err_request_irq;
2786	}
2787
2788	hcd->state = HC_STATE_RUNNING;
2789	retval = hcd->driver->start(hcd);
2790	if (retval < 0) {
2791		dev_err(hcd->self.controller, "startup error %d\n", retval);
2792		goto err_hcd_driver_start;
2793	}
2794
2795	/* starting here, usbcore will pay attention to this root hub */
2796	retval = register_root_hub(hcd);
2797	if (retval != 0)
2798		goto err_register_root_hub;
2799
2800	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
2801		usb_hcd_poll_rh_status(hcd);
2802
2803	return retval;
2804
2805err_register_root_hub:
2806	hcd->rh_pollable = 0;
2807	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2808	del_timer_sync(&hcd->rh_timer);
2809	hcd->driver->stop(hcd);
2810	hcd->state = HC_STATE_HALT;
2811	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2812	del_timer_sync(&hcd->rh_timer);
2813err_hcd_driver_start:
2814	if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0)
2815		free_irq(irqnum, hcd);
2816err_request_irq:
2817err_hcd_driver_setup:
2818err_set_rh_speed:
2819	usb_put_invalidate_rhdev(hcd);
2820err_allocate_root_hub:
2821	usb_deregister_bus(&hcd->self);
2822err_register_bus:
2823	hcd_buffer_destroy(hcd);
2824err_create_buf:
2825	usb_phy_roothub_power_off(hcd->phy_roothub);
2826err_usb_phy_roothub_power_on:
2827	usb_phy_roothub_exit(hcd->phy_roothub);
2828
2829	return retval;
2830}
2831EXPORT_SYMBOL_GPL(usb_add_hcd);
2832
2833/**
2834 * usb_remove_hcd - shutdown processing for generic HCDs
2835 * @hcd: the usb_hcd structure to remove
2836 * Context: !in_interrupt()
2837 *
2838 * Disconnects the root hub, then reverses the effects of usb_add_hcd(),
2839 * invoking the HCD's stop() method.
2840 */
2841void usb_remove_hcd(struct usb_hcd *hcd)
2842{
2843	struct usb_device *rhdev = hcd->self.root_hub;
2844
2845	dev_info(hcd->self.controller, "remove, state %x\n", hcd->state);
2846
2847	usb_get_dev(rhdev);
2848	clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags);
2849	if (HC_IS_RUNNING (hcd->state))
2850		hcd->state = HC_STATE_QUIESCING;
2851
2852	dev_dbg(hcd->self.controller, "roothub graceful disconnect\n");
2853	spin_lock_irq (&hcd_root_hub_lock);
2854	hcd->rh_registered = 0;
2855	spin_unlock_irq (&hcd_root_hub_lock);
2856
2857#ifdef CONFIG_PM
2858	cancel_work_sync(&hcd->wakeup_work);
2859#endif
2860	cancel_work_sync(&hcd->died_work);
2861
2862	mutex_lock(&usb_bus_idr_lock);
2863	usb_disconnect(&rhdev);		/* Sets rhdev to NULL */
2864	mutex_unlock(&usb_bus_idr_lock);
2865
2866	/*
2867	 * tasklet_kill() isn't needed here because:
2868	 * - driver's disconnect() called from usb_disconnect() should
2869	 *   make sure its URBs are completed during the disconnect()
2870	 *   callback
2871	 *
2872	 * - it is too late to run complete() here since driver may have
2873	 *   been removed already now
2874	 */
2875
2876	/* Prevent any more root-hub status calls from the timer.
2877	 * The HCD might still restart the timer (if a port status change
2878	 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke
2879	 * the hub_status_data() callback.
2880	 */
2881	hcd->rh_pollable = 0;
2882	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2883	del_timer_sync(&hcd->rh_timer);
2884
2885	hcd->driver->stop(hcd);
2886	hcd->state = HC_STATE_HALT;
2887
2888	/* In case the HCD restarted the timer, stop it again. */
2889	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
2890	del_timer_sync(&hcd->rh_timer);
2891
2892	if (usb_hcd_is_primary_hcd(hcd)) {
2893		if (hcd->irq > 0)
2894			free_irq(hcd->irq, hcd);
2895	}
2896
2897	usb_deregister_bus(&hcd->self);
2898	hcd_buffer_destroy(hcd);
2899
2900	usb_phy_roothub_power_off(hcd->phy_roothub);
2901	usb_phy_roothub_exit(hcd->phy_roothub);
2902
2903	usb_put_invalidate_rhdev(hcd);
2904	hcd->flags = 0;
2905}
2906EXPORT_SYMBOL_GPL(usb_remove_hcd);
2907
2908void
2909usb_hcd_platform_shutdown(struct platform_device *dev)
2910{
2911	struct usb_hcd *hcd = platform_get_drvdata(dev);
2912
2913	/* No need for pm_runtime_put(), we're shutting down */
2914	pm_runtime_get_sync(&dev->dev);
2915
2916	if (hcd->driver->shutdown)
2917		hcd->driver->shutdown(hcd);
2918}
2919EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown);
2920
2921int usb_hcd_setup_local_mem(struct usb_hcd *hcd, phys_addr_t phys_addr,
2922			    dma_addr_t dma, size_t size)
2923{
2924	int err;
2925	void *local_mem;
2926
2927	hcd->localmem_pool = devm_gen_pool_create(hcd->self.sysdev, 4,
2928						  dev_to_node(hcd->self.sysdev),
2929						  dev_name(hcd->self.sysdev));
2930	if (IS_ERR(hcd->localmem_pool))
2931		return PTR_ERR(hcd->localmem_pool);
2932
2933	local_mem = devm_memremap(hcd->self.sysdev, phys_addr,
2934				  size, MEMREMAP_WC);
2935	if (IS_ERR(local_mem))
2936		return PTR_ERR(local_mem);
2937
2938	/*
2939	 * Here we pass a dma_addr_t but the arg type is a phys_addr_t.
2940	 * It's not backed by system memory and thus there's no kernel mapping
2941	 * for it.
2942	 */
2943	err = gen_pool_add_virt(hcd->localmem_pool, (unsigned long)local_mem,
2944				dma, size, dev_to_node(hcd->self.sysdev));
2945	if (err < 0) {
2946		dev_err(hcd->self.sysdev, "gen_pool_add_virt failed with %d\n",
2947			err);
2948		return err;
2949	}
2950
2951	return 0;
2952}
2953EXPORT_SYMBOL_GPL(usb_hcd_setup_local_mem);
2954
2955/*-------------------------------------------------------------------------*/
2956
2957#if IS_ENABLED(CONFIG_USB_MON)
2958
2959const struct usb_mon_operations *mon_ops;
2960
2961/*
2962 * The registration is unlocked.
2963 * We do it this way because we do not want to lock in hot paths.
2964 *
2965 * Notice that the code is minimally error-proof. Because usbmon needs
2966 * symbols from usbcore, usbcore gets referenced and cannot be unloaded first.
2967 */
2968
2969int usb_mon_register(const struct usb_mon_operations *ops)
2970{
2971
2972	if (mon_ops)
2973		return -EBUSY;
2974
2975	mon_ops = ops;
2976	mb();
2977	return 0;
2978}
2979EXPORT_SYMBOL_GPL (usb_mon_register);
2980
2981void usb_mon_deregister (void)
2982{
2983
2984	if (mon_ops == NULL) {
2985		printk(KERN_ERR "USB: monitor was not registered\n");
2986		return;
2987	}
2988	mon_ops = NULL;
2989	mb();
2990}
2991EXPORT_SYMBOL_GPL (usb_mon_deregister);
2992
2993#endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */