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 33 #include <linux/phy/phy.h> 34 #include <linux/usb.h> 35 #include <linux/usb/hcd.h> 36 #include <linux/usb/otg.h> 37 38 #include "usb.h" 39 #include "phy.h" 40 41 42 /*-------------------------------------------------------------------------*/ 43 44 /* 45 * USB Host Controller Driver framework 46 * 47 * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing 48 * HCD-specific behaviors/bugs. 49 * 50 * This does error checks, tracks devices and urbs, and delegates to a 51 * "hc_driver" only for code (and data) that really needs to know about 52 * hardware differences. That includes root hub registers, i/o queues, 53 * and so on ... but as little else as possible. 54 * 55 * Shared code includes most of the "root hub" code (these are emulated, 56 * though each HC's hardware works differently) and PCI glue, plus request 57 * tracking overhead. The HCD code should only block on spinlocks or on 58 * hardware handshaking; blocking on software events (such as other kernel 59 * threads releasing resources, or completing actions) is all generic. 60 * 61 * Happens the USB 2.0 spec says this would be invisible inside the "USBD", 62 * and includes mostly a "HCDI" (HCD Interface) along with some APIs used 63 * only by the hub driver ... and that neither should be seen or used by 64 * usb client device drivers. 65 * 66 * Contributors of ideas or unattributed patches include: David Brownell, 67 * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ... 68 * 69 * HISTORY: 70 * 2002-02-21 Pull in most of the usb_bus support from usb.c; some 71 * associated cleanup. "usb_hcd" still != "usb_bus". 72 * 2001-12-12 Initial patch version for Linux 2.5.1 kernel. 73 */ 74 75 /*-------------------------------------------------------------------------*/ 76 77 /* Keep track of which host controller drivers are loaded */ 78 unsigned long usb_hcds_loaded; 79 EXPORT_SYMBOL_GPL(usb_hcds_loaded); 80 81 /* host controllers we manage */ 82 DEFINE_IDR (usb_bus_idr); 83 EXPORT_SYMBOL_GPL (usb_bus_idr); 84 85 /* used when allocating bus numbers */ 86 #define USB_MAXBUS 64 87 88 /* used when updating list of hcds */ 89 DEFINE_MUTEX(usb_bus_idr_lock); /* exported only for usbfs */ 90 EXPORT_SYMBOL_GPL (usb_bus_idr_lock); 91 92 /* used for controlling access to virtual root hubs */ 93 static DEFINE_SPINLOCK(hcd_root_hub_lock); 94 95 /* used when updating an endpoint's URB list */ 96 static DEFINE_SPINLOCK(hcd_urb_list_lock); 97 98 /* used to protect against unlinking URBs after the device is gone */ 99 static DEFINE_SPINLOCK(hcd_urb_unlink_lock); 100 101 /* wait queue for synchronous unlinks */ 102 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue); 103 104 static inline int is_root_hub(struct usb_device *udev) 105 { 106 return (udev->parent == NULL); 107 } 108 109 /*-------------------------------------------------------------------------*/ 110 111 /* 112 * Sharable chunks of root hub code. 113 */ 114 115 /*-------------------------------------------------------------------------*/ 116 #define KERNEL_REL bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff)) 117 #define KERNEL_VER bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff)) 118 119 /* usb 3.1 root hub device descriptor */ 120 static const u8 usb31_rh_dev_descriptor[18] = { 121 0x12, /* __u8 bLength; */ 122 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 123 0x10, 0x03, /* __le16 bcdUSB; v3.1 */ 124 125 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 126 0x00, /* __u8 bDeviceSubClass; */ 127 0x03, /* __u8 bDeviceProtocol; USB 3 hub */ 128 0x09, /* __u8 bMaxPacketSize0; 2^9 = 512 Bytes */ 129 130 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 131 0x03, 0x00, /* __le16 idProduct; device 0x0003 */ 132 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 133 134 0x03, /* __u8 iManufacturer; */ 135 0x02, /* __u8 iProduct; */ 136 0x01, /* __u8 iSerialNumber; */ 137 0x01 /* __u8 bNumConfigurations; */ 138 }; 139 140 /* usb 3.0 root hub device descriptor */ 141 static const u8 usb3_rh_dev_descriptor[18] = { 142 0x12, /* __u8 bLength; */ 143 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 144 0x00, 0x03, /* __le16 bcdUSB; v3.0 */ 145 146 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 147 0x00, /* __u8 bDeviceSubClass; */ 148 0x03, /* __u8 bDeviceProtocol; USB 3.0 hub */ 149 0x09, /* __u8 bMaxPacketSize0; 2^9 = 512 Bytes */ 150 151 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 152 0x03, 0x00, /* __le16 idProduct; device 0x0003 */ 153 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 154 155 0x03, /* __u8 iManufacturer; */ 156 0x02, /* __u8 iProduct; */ 157 0x01, /* __u8 iSerialNumber; */ 158 0x01 /* __u8 bNumConfigurations; */ 159 }; 160 161 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */ 162 static const u8 usb25_rh_dev_descriptor[18] = { 163 0x12, /* __u8 bLength; */ 164 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 165 0x50, 0x02, /* __le16 bcdUSB; v2.5 */ 166 167 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 168 0x00, /* __u8 bDeviceSubClass; */ 169 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */ 170 0xFF, /* __u8 bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */ 171 172 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 173 0x02, 0x00, /* __le16 idProduct; device 0x0002 */ 174 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 175 176 0x03, /* __u8 iManufacturer; */ 177 0x02, /* __u8 iProduct; */ 178 0x01, /* __u8 iSerialNumber; */ 179 0x01 /* __u8 bNumConfigurations; */ 180 }; 181 182 /* usb 2.0 root hub device descriptor */ 183 static const u8 usb2_rh_dev_descriptor[18] = { 184 0x12, /* __u8 bLength; */ 185 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 186 0x00, 0x02, /* __le16 bcdUSB; v2.0 */ 187 188 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 189 0x00, /* __u8 bDeviceSubClass; */ 190 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */ 191 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */ 192 193 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 194 0x02, 0x00, /* __le16 idProduct; device 0x0002 */ 195 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 196 197 0x03, /* __u8 iManufacturer; */ 198 0x02, /* __u8 iProduct; */ 199 0x01, /* __u8 iSerialNumber; */ 200 0x01 /* __u8 bNumConfigurations; */ 201 }; 202 203 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */ 204 205 /* usb 1.1 root hub device descriptor */ 206 static const u8 usb11_rh_dev_descriptor[18] = { 207 0x12, /* __u8 bLength; */ 208 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 209 0x10, 0x01, /* __le16 bcdUSB; v1.1 */ 210 211 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 212 0x00, /* __u8 bDeviceSubClass; */ 213 0x00, /* __u8 bDeviceProtocol; [ low/full speeds only ] */ 214 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */ 215 216 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 217 0x01, 0x00, /* __le16 idProduct; device 0x0001 */ 218 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 219 220 0x03, /* __u8 iManufacturer; */ 221 0x02, /* __u8 iProduct; */ 222 0x01, /* __u8 iSerialNumber; */ 223 0x01 /* __u8 bNumConfigurations; */ 224 }; 225 226 227 /*-------------------------------------------------------------------------*/ 228 229 /* Configuration descriptors for our root hubs */ 230 231 static const u8 fs_rh_config_descriptor[] = { 232 233 /* one configuration */ 234 0x09, /* __u8 bLength; */ 235 USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */ 236 0x19, 0x00, /* __le16 wTotalLength; */ 237 0x01, /* __u8 bNumInterfaces; (1) */ 238 0x01, /* __u8 bConfigurationValue; */ 239 0x00, /* __u8 iConfiguration; */ 240 0xc0, /* __u8 bmAttributes; 241 Bit 7: must be set, 242 6: Self-powered, 243 5: Remote wakeup, 244 4..0: resvd */ 245 0x00, /* __u8 MaxPower; */ 246 247 /* USB 1.1: 248 * USB 2.0, single TT organization (mandatory): 249 * one interface, protocol 0 250 * 251 * USB 2.0, multiple TT organization (optional): 252 * two interfaces, protocols 1 (like single TT) 253 * and 2 (multiple TT mode) ... config is 254 * sometimes settable 255 * NOT IMPLEMENTED 256 */ 257 258 /* one interface */ 259 0x09, /* __u8 if_bLength; */ 260 USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */ 261 0x00, /* __u8 if_bInterfaceNumber; */ 262 0x00, /* __u8 if_bAlternateSetting; */ 263 0x01, /* __u8 if_bNumEndpoints; */ 264 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ 265 0x00, /* __u8 if_bInterfaceSubClass; */ 266 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */ 267 0x00, /* __u8 if_iInterface; */ 268 269 /* one endpoint (status change endpoint) */ 270 0x07, /* __u8 ep_bLength; */ 271 USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 272 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 273 0x03, /* __u8 ep_bmAttributes; Interrupt */ 274 0x02, 0x00, /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */ 275 0xff /* __u8 ep_bInterval; (255ms -- usb 2.0 spec) */ 276 }; 277 278 static const u8 hs_rh_config_descriptor[] = { 279 280 /* one configuration */ 281 0x09, /* __u8 bLength; */ 282 USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */ 283 0x19, 0x00, /* __le16 wTotalLength; */ 284 0x01, /* __u8 bNumInterfaces; (1) */ 285 0x01, /* __u8 bConfigurationValue; */ 286 0x00, /* __u8 iConfiguration; */ 287 0xc0, /* __u8 bmAttributes; 288 Bit 7: must be set, 289 6: Self-powered, 290 5: Remote wakeup, 291 4..0: resvd */ 292 0x00, /* __u8 MaxPower; */ 293 294 /* USB 1.1: 295 * USB 2.0, single TT organization (mandatory): 296 * one interface, protocol 0 297 * 298 * USB 2.0, multiple TT organization (optional): 299 * two interfaces, protocols 1 (like single TT) 300 * and 2 (multiple TT mode) ... config is 301 * sometimes settable 302 * NOT IMPLEMENTED 303 */ 304 305 /* one interface */ 306 0x09, /* __u8 if_bLength; */ 307 USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */ 308 0x00, /* __u8 if_bInterfaceNumber; */ 309 0x00, /* __u8 if_bAlternateSetting; */ 310 0x01, /* __u8 if_bNumEndpoints; */ 311 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ 312 0x00, /* __u8 if_bInterfaceSubClass; */ 313 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */ 314 0x00, /* __u8 if_iInterface; */ 315 316 /* one endpoint (status change endpoint) */ 317 0x07, /* __u8 ep_bLength; */ 318 USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 319 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 320 0x03, /* __u8 ep_bmAttributes; Interrupt */ 321 /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) 322 * see hub.c:hub_configure() for details. */ 323 (USB_MAXCHILDREN + 1 + 7) / 8, 0x00, 324 0x0c /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */ 325 }; 326 327 static const u8 ss_rh_config_descriptor[] = { 328 /* one configuration */ 329 0x09, /* __u8 bLength; */ 330 USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */ 331 0x1f, 0x00, /* __le16 wTotalLength; */ 332 0x01, /* __u8 bNumInterfaces; (1) */ 333 0x01, /* __u8 bConfigurationValue; */ 334 0x00, /* __u8 iConfiguration; */ 335 0xc0, /* __u8 bmAttributes; 336 Bit 7: must be set, 337 6: Self-powered, 338 5: Remote wakeup, 339 4..0: resvd */ 340 0x00, /* __u8 MaxPower; */ 341 342 /* one interface */ 343 0x09, /* __u8 if_bLength; */ 344 USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */ 345 0x00, /* __u8 if_bInterfaceNumber; */ 346 0x00, /* __u8 if_bAlternateSetting; */ 347 0x01, /* __u8 if_bNumEndpoints; */ 348 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ 349 0x00, /* __u8 if_bInterfaceSubClass; */ 350 0x00, /* __u8 if_bInterfaceProtocol; */ 351 0x00, /* __u8 if_iInterface; */ 352 353 /* one endpoint (status change endpoint) */ 354 0x07, /* __u8 ep_bLength; */ 355 USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 356 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 357 0x03, /* __u8 ep_bmAttributes; Interrupt */ 358 /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) 359 * see hub.c:hub_configure() for details. */ 360 (USB_MAXCHILDREN + 1 + 7) / 8, 0x00, 361 0x0c, /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */ 362 363 /* one SuperSpeed endpoint companion descriptor */ 364 0x06, /* __u8 ss_bLength */ 365 USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */ 366 /* Companion */ 367 0x00, /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */ 368 0x00, /* __u8 ss_bmAttributes; 1 packet per service interval */ 369 0x02, 0x00 /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */ 370 }; 371 372 /* authorized_default behaviour: 373 * -1 is authorized for all devices except wireless (old behaviour) 374 * 0 is unauthorized for all devices 375 * 1 is authorized for all devices 376 * 2 is authorized for internal devices 377 */ 378 #define USB_AUTHORIZE_WIRED -1 379 #define USB_AUTHORIZE_NONE 0 380 #define USB_AUTHORIZE_ALL 1 381 #define USB_AUTHORIZE_INTERNAL 2 382 383 static int authorized_default = USB_AUTHORIZE_WIRED; 384 module_param(authorized_default, int, S_IRUGO|S_IWUSR); 385 MODULE_PARM_DESC(authorized_default, 386 "Default USB device authorization: 0 is not authorized, 1 is " 387 "authorized, 2 is authorized for internal devices, -1 is " 388 "authorized except for wireless USB (default, old behaviour)"); 389 /*-------------------------------------------------------------------------*/ 390 391 /** 392 * ascii2desc() - Helper routine for producing UTF-16LE string descriptors 393 * @s: Null-terminated ASCII (actually ISO-8859-1) string 394 * @buf: Buffer for USB string descriptor (header + UTF-16LE) 395 * @len: Length (in bytes; may be odd) of descriptor buffer. 396 * 397 * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len, 398 * whichever is less. 399 * 400 * Note: 401 * USB String descriptors can contain at most 126 characters; input 402 * strings longer than that are truncated. 403 */ 404 static unsigned 405 ascii2desc(char const *s, u8 *buf, unsigned len) 406 { 407 unsigned n, t = 2 + 2*strlen(s); 408 409 if (t > 254) 410 t = 254; /* Longest possible UTF string descriptor */ 411 if (len > t) 412 len = t; 413 414 t += USB_DT_STRING << 8; /* Now t is first 16 bits to store */ 415 416 n = len; 417 while (n--) { 418 *buf++ = t; 419 if (!n--) 420 break; 421 *buf++ = t >> 8; 422 t = (unsigned char)*s++; 423 } 424 return len; 425 } 426 427 /** 428 * rh_string() - provides string descriptors for root hub 429 * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor) 430 * @hcd: the host controller for this root hub 431 * @data: buffer for output packet 432 * @len: length of the provided buffer 433 * 434 * Produces either a manufacturer, product or serial number string for the 435 * virtual root hub device. 436 * 437 * Return: The number of bytes filled in: the length of the descriptor or 438 * of the provided buffer, whichever is less. 439 */ 440 static unsigned 441 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len) 442 { 443 char buf[100]; 444 char const *s; 445 static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04}; 446 447 /* language ids */ 448 switch (id) { 449 case 0: 450 /* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */ 451 /* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */ 452 if (len > 4) 453 len = 4; 454 memcpy(data, langids, len); 455 return len; 456 case 1: 457 /* Serial number */ 458 s = hcd->self.bus_name; 459 break; 460 case 2: 461 /* Product name */ 462 s = hcd->product_desc; 463 break; 464 case 3: 465 /* Manufacturer */ 466 snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname, 467 init_utsname()->release, hcd->driver->description); 468 s = buf; 469 break; 470 default: 471 /* Can't happen; caller guarantees it */ 472 return 0; 473 } 474 475 return ascii2desc(s, data, len); 476 } 477 478 479 /* Root hub control transfers execute synchronously */ 480 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb) 481 { 482 struct usb_ctrlrequest *cmd; 483 u16 typeReq, wValue, wIndex, wLength; 484 u8 *ubuf = urb->transfer_buffer; 485 unsigned len = 0; 486 int status; 487 u8 patch_wakeup = 0; 488 u8 patch_protocol = 0; 489 u16 tbuf_size; 490 u8 *tbuf = NULL; 491 const u8 *bufp; 492 493 might_sleep(); 494 495 spin_lock_irq(&hcd_root_hub_lock); 496 status = usb_hcd_link_urb_to_ep(hcd, urb); 497 spin_unlock_irq(&hcd_root_hub_lock); 498 if (status) 499 return status; 500 urb->hcpriv = hcd; /* Indicate it's queued */ 501 502 cmd = (struct usb_ctrlrequest *) urb->setup_packet; 503 typeReq = (cmd->bRequestType << 8) | cmd->bRequest; 504 wValue = le16_to_cpu (cmd->wValue); 505 wIndex = le16_to_cpu (cmd->wIndex); 506 wLength = le16_to_cpu (cmd->wLength); 507 508 if (wLength > urb->transfer_buffer_length) 509 goto error; 510 511 /* 512 * tbuf should be at least as big as the 513 * USB hub descriptor. 514 */ 515 tbuf_size = max_t(u16, sizeof(struct usb_hub_descriptor), wLength); 516 tbuf = kzalloc(tbuf_size, GFP_KERNEL); 517 if (!tbuf) { 518 status = -ENOMEM; 519 goto err_alloc; 520 } 521 522 bufp = tbuf; 523 524 525 urb->actual_length = 0; 526 switch (typeReq) { 527 528 /* DEVICE REQUESTS */ 529 530 /* The root hub's remote wakeup enable bit is implemented using 531 * driver model wakeup flags. If this system supports wakeup 532 * through USB, userspace may change the default "allow wakeup" 533 * policy through sysfs or these calls. 534 * 535 * Most root hubs support wakeup from downstream devices, for 536 * runtime power management (disabling USB clocks and reducing 537 * VBUS power usage). However, not all of them do so; silicon, 538 * board, and BIOS bugs here are not uncommon, so these can't 539 * be treated quite like external hubs. 540 * 541 * Likewise, not all root hubs will pass wakeup events upstream, 542 * to wake up the whole system. So don't assume root hub and 543 * controller capabilities are identical. 544 */ 545 546 case DeviceRequest | USB_REQ_GET_STATUS: 547 tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev) 548 << USB_DEVICE_REMOTE_WAKEUP) 549 | (1 << USB_DEVICE_SELF_POWERED); 550 tbuf[1] = 0; 551 len = 2; 552 break; 553 case DeviceOutRequest | USB_REQ_CLEAR_FEATURE: 554 if (wValue == USB_DEVICE_REMOTE_WAKEUP) 555 device_set_wakeup_enable(&hcd->self.root_hub->dev, 0); 556 else 557 goto error; 558 break; 559 case DeviceOutRequest | USB_REQ_SET_FEATURE: 560 if (device_can_wakeup(&hcd->self.root_hub->dev) 561 && wValue == USB_DEVICE_REMOTE_WAKEUP) 562 device_set_wakeup_enable(&hcd->self.root_hub->dev, 1); 563 else 564 goto error; 565 break; 566 case DeviceRequest | USB_REQ_GET_CONFIGURATION: 567 tbuf[0] = 1; 568 len = 1; 569 /* FALLTHROUGH */ 570 case DeviceOutRequest | USB_REQ_SET_CONFIGURATION: 571 break; 572 case DeviceRequest | USB_REQ_GET_DESCRIPTOR: 573 switch (wValue & 0xff00) { 574 case USB_DT_DEVICE << 8: 575 switch (hcd->speed) { 576 case HCD_USB32: 577 case HCD_USB31: 578 bufp = usb31_rh_dev_descriptor; 579 break; 580 case HCD_USB3: 581 bufp = usb3_rh_dev_descriptor; 582 break; 583 case HCD_USB25: 584 bufp = usb25_rh_dev_descriptor; 585 break; 586 case HCD_USB2: 587 bufp = usb2_rh_dev_descriptor; 588 break; 589 case HCD_USB11: 590 bufp = usb11_rh_dev_descriptor; 591 break; 592 default: 593 goto error; 594 } 595 len = 18; 596 if (hcd->has_tt) 597 patch_protocol = 1; 598 break; 599 case USB_DT_CONFIG << 8: 600 switch (hcd->speed) { 601 case HCD_USB32: 602 case HCD_USB31: 603 case HCD_USB3: 604 bufp = ss_rh_config_descriptor; 605 len = sizeof ss_rh_config_descriptor; 606 break; 607 case HCD_USB25: 608 case HCD_USB2: 609 bufp = hs_rh_config_descriptor; 610 len = sizeof hs_rh_config_descriptor; 611 break; 612 case HCD_USB11: 613 bufp = fs_rh_config_descriptor; 614 len = sizeof fs_rh_config_descriptor; 615 break; 616 default: 617 goto error; 618 } 619 if (device_can_wakeup(&hcd->self.root_hub->dev)) 620 patch_wakeup = 1; 621 break; 622 case USB_DT_STRING << 8: 623 if ((wValue & 0xff) < 4) 624 urb->actual_length = rh_string(wValue & 0xff, 625 hcd, ubuf, wLength); 626 else /* unsupported IDs --> "protocol stall" */ 627 goto error; 628 break; 629 case USB_DT_BOS << 8: 630 goto nongeneric; 631 default: 632 goto error; 633 } 634 break; 635 case DeviceRequest | USB_REQ_GET_INTERFACE: 636 tbuf[0] = 0; 637 len = 1; 638 /* FALLTHROUGH */ 639 case DeviceOutRequest | USB_REQ_SET_INTERFACE: 640 break; 641 case DeviceOutRequest | USB_REQ_SET_ADDRESS: 642 /* wValue == urb->dev->devaddr */ 643 dev_dbg (hcd->self.controller, "root hub device address %d\n", 644 wValue); 645 break; 646 647 /* INTERFACE REQUESTS (no defined feature/status flags) */ 648 649 /* ENDPOINT REQUESTS */ 650 651 case EndpointRequest | USB_REQ_GET_STATUS: 652 /* ENDPOINT_HALT flag */ 653 tbuf[0] = 0; 654 tbuf[1] = 0; 655 len = 2; 656 /* FALLTHROUGH */ 657 case EndpointOutRequest | USB_REQ_CLEAR_FEATURE: 658 case EndpointOutRequest | USB_REQ_SET_FEATURE: 659 dev_dbg (hcd->self.controller, "no endpoint features yet\n"); 660 break; 661 662 /* CLASS REQUESTS (and errors) */ 663 664 default: 665 nongeneric: 666 /* non-generic request */ 667 switch (typeReq) { 668 case GetHubStatus: 669 len = 4; 670 break; 671 case GetPortStatus: 672 if (wValue == HUB_PORT_STATUS) 673 len = 4; 674 else 675 /* other port status types return 8 bytes */ 676 len = 8; 677 break; 678 case GetHubDescriptor: 679 len = sizeof (struct usb_hub_descriptor); 680 break; 681 case DeviceRequest | USB_REQ_GET_DESCRIPTOR: 682 /* len is returned by hub_control */ 683 break; 684 } 685 status = hcd->driver->hub_control (hcd, 686 typeReq, wValue, wIndex, 687 tbuf, wLength); 688 689 if (typeReq == GetHubDescriptor) 690 usb_hub_adjust_deviceremovable(hcd->self.root_hub, 691 (struct usb_hub_descriptor *)tbuf); 692 break; 693 error: 694 /* "protocol stall" on error */ 695 status = -EPIPE; 696 } 697 698 if (status < 0) { 699 len = 0; 700 if (status != -EPIPE) { 701 dev_dbg (hcd->self.controller, 702 "CTRL: TypeReq=0x%x val=0x%x " 703 "idx=0x%x len=%d ==> %d\n", 704 typeReq, wValue, wIndex, 705 wLength, status); 706 } 707 } else if (status > 0) { 708 /* hub_control may return the length of data copied. */ 709 len = status; 710 status = 0; 711 } 712 if (len) { 713 if (urb->transfer_buffer_length < len) 714 len = urb->transfer_buffer_length; 715 urb->actual_length = len; 716 /* always USB_DIR_IN, toward host */ 717 memcpy (ubuf, bufp, len); 718 719 /* report whether RH hardware supports remote wakeup */ 720 if (patch_wakeup && 721 len > offsetof (struct usb_config_descriptor, 722 bmAttributes)) 723 ((struct usb_config_descriptor *)ubuf)->bmAttributes 724 |= USB_CONFIG_ATT_WAKEUP; 725 726 /* report whether RH hardware has an integrated TT */ 727 if (patch_protocol && 728 len > offsetof(struct usb_device_descriptor, 729 bDeviceProtocol)) 730 ((struct usb_device_descriptor *) ubuf)-> 731 bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT; 732 } 733 734 kfree(tbuf); 735 err_alloc: 736 737 /* any errors get returned through the urb completion */ 738 spin_lock_irq(&hcd_root_hub_lock); 739 usb_hcd_unlink_urb_from_ep(hcd, urb); 740 usb_hcd_giveback_urb(hcd, urb, status); 741 spin_unlock_irq(&hcd_root_hub_lock); 742 return 0; 743 } 744 745 /*-------------------------------------------------------------------------*/ 746 747 /* 748 * Root Hub interrupt transfers are polled using a timer if the 749 * driver requests it; otherwise the driver is responsible for 750 * calling usb_hcd_poll_rh_status() when an event occurs. 751 * 752 * Completions are called in_interrupt(), but they may or may not 753 * be in_irq(). 754 */ 755 void usb_hcd_poll_rh_status(struct usb_hcd *hcd) 756 { 757 struct urb *urb; 758 int length; 759 unsigned long flags; 760 char buffer[6]; /* Any root hubs with > 31 ports? */ 761 762 if (unlikely(!hcd->rh_pollable)) 763 return; 764 if (!hcd->uses_new_polling && !hcd->status_urb) 765 return; 766 767 length = hcd->driver->hub_status_data(hcd, buffer); 768 if (length > 0) { 769 770 /* try to complete the status urb */ 771 spin_lock_irqsave(&hcd_root_hub_lock, flags); 772 urb = hcd->status_urb; 773 if (urb) { 774 clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags); 775 hcd->status_urb = NULL; 776 urb->actual_length = length; 777 memcpy(urb->transfer_buffer, buffer, length); 778 779 usb_hcd_unlink_urb_from_ep(hcd, urb); 780 usb_hcd_giveback_urb(hcd, urb, 0); 781 } else { 782 length = 0; 783 set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags); 784 } 785 spin_unlock_irqrestore(&hcd_root_hub_lock, flags); 786 } 787 788 /* The USB 2.0 spec says 256 ms. This is close enough and won't 789 * exceed that limit if HZ is 100. The math is more clunky than 790 * maybe expected, this is to make sure that all timers for USB devices 791 * fire at the same time to give the CPU a break in between */ 792 if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) : 793 (length == 0 && hcd->status_urb != NULL)) 794 mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4)); 795 } 796 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status); 797 798 /* timer callback */ 799 static void rh_timer_func (struct timer_list *t) 800 { 801 struct usb_hcd *_hcd = from_timer(_hcd, t, rh_timer); 802 803 usb_hcd_poll_rh_status(_hcd); 804 } 805 806 /*-------------------------------------------------------------------------*/ 807 808 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb) 809 { 810 int retval; 811 unsigned long flags; 812 unsigned len = 1 + (urb->dev->maxchild / 8); 813 814 spin_lock_irqsave (&hcd_root_hub_lock, flags); 815 if (hcd->status_urb || urb->transfer_buffer_length < len) { 816 dev_dbg (hcd->self.controller, "not queuing rh status urb\n"); 817 retval = -EINVAL; 818 goto done; 819 } 820 821 retval = usb_hcd_link_urb_to_ep(hcd, urb); 822 if (retval) 823 goto done; 824 825 hcd->status_urb = urb; 826 urb->hcpriv = hcd; /* indicate it's queued */ 827 if (!hcd->uses_new_polling) 828 mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4)); 829 830 /* If a status change has already occurred, report it ASAP */ 831 else if (HCD_POLL_PENDING(hcd)) 832 mod_timer(&hcd->rh_timer, jiffies); 833 retval = 0; 834 done: 835 spin_unlock_irqrestore (&hcd_root_hub_lock, flags); 836 return retval; 837 } 838 839 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb) 840 { 841 if (usb_endpoint_xfer_int(&urb->ep->desc)) 842 return rh_queue_status (hcd, urb); 843 if (usb_endpoint_xfer_control(&urb->ep->desc)) 844 return rh_call_control (hcd, urb); 845 return -EINVAL; 846 } 847 848 /*-------------------------------------------------------------------------*/ 849 850 /* Unlinks of root-hub control URBs are legal, but they don't do anything 851 * since these URBs always execute synchronously. 852 */ 853 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status) 854 { 855 unsigned long flags; 856 int rc; 857 858 spin_lock_irqsave(&hcd_root_hub_lock, flags); 859 rc = usb_hcd_check_unlink_urb(hcd, urb, status); 860 if (rc) 861 goto done; 862 863 if (usb_endpoint_num(&urb->ep->desc) == 0) { /* Control URB */ 864 ; /* Do nothing */ 865 866 } else { /* Status URB */ 867 if (!hcd->uses_new_polling) 868 del_timer (&hcd->rh_timer); 869 if (urb == hcd->status_urb) { 870 hcd->status_urb = NULL; 871 usb_hcd_unlink_urb_from_ep(hcd, urb); 872 usb_hcd_giveback_urb(hcd, urb, status); 873 } 874 } 875 done: 876 spin_unlock_irqrestore(&hcd_root_hub_lock, flags); 877 return rc; 878 } 879 880 881 882 /* 883 * Show & store the current value of authorized_default 884 */ 885 static ssize_t authorized_default_show(struct device *dev, 886 struct device_attribute *attr, char *buf) 887 { 888 struct usb_device *rh_usb_dev = to_usb_device(dev); 889 struct usb_bus *usb_bus = rh_usb_dev->bus; 890 struct usb_hcd *hcd; 891 892 hcd = bus_to_hcd(usb_bus); 893 return snprintf(buf, PAGE_SIZE, "%u\n", hcd->dev_policy); 894 } 895 896 static ssize_t authorized_default_store(struct device *dev, 897 struct device_attribute *attr, 898 const char *buf, size_t size) 899 { 900 ssize_t result; 901 unsigned val; 902 struct usb_device *rh_usb_dev = to_usb_device(dev); 903 struct usb_bus *usb_bus = rh_usb_dev->bus; 904 struct usb_hcd *hcd; 905 906 hcd = bus_to_hcd(usb_bus); 907 result = sscanf(buf, "%u\n", &val); 908 if (result == 1) { 909 hcd->dev_policy = val <= USB_DEVICE_AUTHORIZE_INTERNAL ? 910 val : USB_DEVICE_AUTHORIZE_ALL; 911 result = size; 912 } else { 913 result = -EINVAL; 914 } 915 return result; 916 } 917 static DEVICE_ATTR_RW(authorized_default); 918 919 /* 920 * interface_authorized_default_show - show default authorization status 921 * for USB interfaces 922 * 923 * note: interface_authorized_default is the default value 924 * for initializing the authorized attribute of interfaces 925 */ 926 static ssize_t interface_authorized_default_show(struct device *dev, 927 struct device_attribute *attr, char *buf) 928 { 929 struct usb_device *usb_dev = to_usb_device(dev); 930 struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus); 931 932 return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd)); 933 } 934 935 /* 936 * interface_authorized_default_store - store default authorization status 937 * for USB interfaces 938 * 939 * note: interface_authorized_default is the default value 940 * for initializing the authorized attribute of interfaces 941 */ 942 static ssize_t interface_authorized_default_store(struct device *dev, 943 struct device_attribute *attr, const char *buf, size_t count) 944 { 945 struct usb_device *usb_dev = to_usb_device(dev); 946 struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus); 947 int rc = count; 948 bool val; 949 950 if (strtobool(buf, &val) != 0) 951 return -EINVAL; 952 953 if (val) 954 set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); 955 else 956 clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); 957 958 return rc; 959 } 960 static DEVICE_ATTR_RW(interface_authorized_default); 961 962 /* Group all the USB bus attributes */ 963 static struct attribute *usb_bus_attrs[] = { 964 &dev_attr_authorized_default.attr, 965 &dev_attr_interface_authorized_default.attr, 966 NULL, 967 }; 968 969 static const struct attribute_group usb_bus_attr_group = { 970 .name = NULL, /* we want them in the same directory */ 971 .attrs = usb_bus_attrs, 972 }; 973 974 975 976 /*-------------------------------------------------------------------------*/ 977 978 /** 979 * usb_bus_init - shared initialization code 980 * @bus: the bus structure being initialized 981 * 982 * This code is used to initialize a usb_bus structure, memory for which is 983 * separately managed. 984 */ 985 static void usb_bus_init (struct usb_bus *bus) 986 { 987 memset (&bus->devmap, 0, sizeof(struct usb_devmap)); 988 989 bus->devnum_next = 1; 990 991 bus->root_hub = NULL; 992 bus->busnum = -1; 993 bus->bandwidth_allocated = 0; 994 bus->bandwidth_int_reqs = 0; 995 bus->bandwidth_isoc_reqs = 0; 996 mutex_init(&bus->devnum_next_mutex); 997 } 998 999 /*-------------------------------------------------------------------------*/ 1000 1001 /** 1002 * usb_register_bus - registers the USB host controller with the usb core 1003 * @bus: pointer to the bus to register 1004 * Context: !in_interrupt() 1005 * 1006 * Assigns a bus number, and links the controller into usbcore data 1007 * structures so that it can be seen by scanning the bus list. 1008 * 1009 * Return: 0 if successful. A negative error code otherwise. 1010 */ 1011 static int usb_register_bus(struct usb_bus *bus) 1012 { 1013 int result = -E2BIG; 1014 int busnum; 1015 1016 mutex_lock(&usb_bus_idr_lock); 1017 busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL); 1018 if (busnum < 0) { 1019 pr_err("%s: failed to get bus number\n", usbcore_name); 1020 goto error_find_busnum; 1021 } 1022 bus->busnum = busnum; 1023 mutex_unlock(&usb_bus_idr_lock); 1024 1025 usb_notify_add_bus(bus); 1026 1027 dev_info (bus->controller, "new USB bus registered, assigned bus " 1028 "number %d\n", bus->busnum); 1029 return 0; 1030 1031 error_find_busnum: 1032 mutex_unlock(&usb_bus_idr_lock); 1033 return result; 1034 } 1035 1036 /** 1037 * usb_deregister_bus - deregisters the USB host controller 1038 * @bus: pointer to the bus to deregister 1039 * Context: !in_interrupt() 1040 * 1041 * Recycles the bus number, and unlinks the controller from usbcore data 1042 * structures so that it won't be seen by scanning the bus list. 1043 */ 1044 static void usb_deregister_bus (struct usb_bus *bus) 1045 { 1046 dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum); 1047 1048 /* 1049 * NOTE: make sure that all the devices are removed by the 1050 * controller code, as well as having it call this when cleaning 1051 * itself up 1052 */ 1053 mutex_lock(&usb_bus_idr_lock); 1054 idr_remove(&usb_bus_idr, bus->busnum); 1055 mutex_unlock(&usb_bus_idr_lock); 1056 1057 usb_notify_remove_bus(bus); 1058 } 1059 1060 /** 1061 * register_root_hub - called by usb_add_hcd() to register a root hub 1062 * @hcd: host controller for this root hub 1063 * 1064 * This function registers the root hub with the USB subsystem. It sets up 1065 * the device properly in the device tree and then calls usb_new_device() 1066 * to register the usb device. It also assigns the root hub's USB address 1067 * (always 1). 1068 * 1069 * Return: 0 if successful. A negative error code otherwise. 1070 */ 1071 static int register_root_hub(struct usb_hcd *hcd) 1072 { 1073 struct device *parent_dev = hcd->self.controller; 1074 struct usb_device *usb_dev = hcd->self.root_hub; 1075 const int devnum = 1; 1076 int retval; 1077 1078 usb_dev->devnum = devnum; 1079 usb_dev->bus->devnum_next = devnum + 1; 1080 set_bit (devnum, usb_dev->bus->devmap.devicemap); 1081 usb_set_device_state(usb_dev, USB_STATE_ADDRESS); 1082 1083 mutex_lock(&usb_bus_idr_lock); 1084 1085 usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64); 1086 retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE); 1087 if (retval != sizeof usb_dev->descriptor) { 1088 mutex_unlock(&usb_bus_idr_lock); 1089 dev_dbg (parent_dev, "can't read %s device descriptor %d\n", 1090 dev_name(&usb_dev->dev), retval); 1091 return (retval < 0) ? retval : -EMSGSIZE; 1092 } 1093 1094 if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) { 1095 retval = usb_get_bos_descriptor(usb_dev); 1096 if (!retval) { 1097 usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev); 1098 } else if (usb_dev->speed >= USB_SPEED_SUPER) { 1099 mutex_unlock(&usb_bus_idr_lock); 1100 dev_dbg(parent_dev, "can't read %s bos descriptor %d\n", 1101 dev_name(&usb_dev->dev), retval); 1102 return retval; 1103 } 1104 } 1105 1106 retval = usb_new_device (usb_dev); 1107 if (retval) { 1108 dev_err (parent_dev, "can't register root hub for %s, %d\n", 1109 dev_name(&usb_dev->dev), retval); 1110 } else { 1111 spin_lock_irq (&hcd_root_hub_lock); 1112 hcd->rh_registered = 1; 1113 spin_unlock_irq (&hcd_root_hub_lock); 1114 1115 /* Did the HC die before the root hub was registered? */ 1116 if (HCD_DEAD(hcd)) 1117 usb_hc_died (hcd); /* This time clean up */ 1118 } 1119 mutex_unlock(&usb_bus_idr_lock); 1120 1121 return retval; 1122 } 1123 1124 /* 1125 * usb_hcd_start_port_resume - a root-hub port is sending a resume signal 1126 * @bus: the bus which the root hub belongs to 1127 * @portnum: the port which is being resumed 1128 * 1129 * HCDs should call this function when they know that a resume signal is 1130 * being sent to a root-hub port. The root hub will be prevented from 1131 * going into autosuspend until usb_hcd_end_port_resume() is called. 1132 * 1133 * The bus's private lock must be held by the caller. 1134 */ 1135 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum) 1136 { 1137 unsigned bit = 1 << portnum; 1138 1139 if (!(bus->resuming_ports & bit)) { 1140 bus->resuming_ports |= bit; 1141 pm_runtime_get_noresume(&bus->root_hub->dev); 1142 } 1143 } 1144 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume); 1145 1146 /* 1147 * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal 1148 * @bus: the bus which the root hub belongs to 1149 * @portnum: the port which is being resumed 1150 * 1151 * HCDs should call this function when they know that a resume signal has 1152 * stopped being sent to a root-hub port. The root hub will be allowed to 1153 * autosuspend again. 1154 * 1155 * The bus's private lock must be held by the caller. 1156 */ 1157 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum) 1158 { 1159 unsigned bit = 1 << portnum; 1160 1161 if (bus->resuming_ports & bit) { 1162 bus->resuming_ports &= ~bit; 1163 pm_runtime_put_noidle(&bus->root_hub->dev); 1164 } 1165 } 1166 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume); 1167 1168 /*-------------------------------------------------------------------------*/ 1169 1170 /** 1171 * usb_calc_bus_time - approximate periodic transaction time in nanoseconds 1172 * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH} 1173 * @is_input: true iff the transaction sends data to the host 1174 * @isoc: true for isochronous transactions, false for interrupt ones 1175 * @bytecount: how many bytes in the transaction. 1176 * 1177 * Return: Approximate bus time in nanoseconds for a periodic transaction. 1178 * 1179 * Note: 1180 * See USB 2.0 spec section 5.11.3; only periodic transfers need to be 1181 * scheduled in software, this function is only used for such scheduling. 1182 */ 1183 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount) 1184 { 1185 unsigned long tmp; 1186 1187 switch (speed) { 1188 case USB_SPEED_LOW: /* INTR only */ 1189 if (is_input) { 1190 tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L; 1191 return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp; 1192 } else { 1193 tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L; 1194 return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp; 1195 } 1196 case USB_SPEED_FULL: /* ISOC or INTR */ 1197 if (isoc) { 1198 tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L; 1199 return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp; 1200 } else { 1201 tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L; 1202 return 9107L + BW_HOST_DELAY + tmp; 1203 } 1204 case USB_SPEED_HIGH: /* ISOC or INTR */ 1205 /* FIXME adjust for input vs output */ 1206 if (isoc) 1207 tmp = HS_NSECS_ISO (bytecount); 1208 else 1209 tmp = HS_NSECS (bytecount); 1210 return tmp; 1211 default: 1212 pr_debug ("%s: bogus device speed!\n", usbcore_name); 1213 return -1; 1214 } 1215 } 1216 EXPORT_SYMBOL_GPL(usb_calc_bus_time); 1217 1218 1219 /*-------------------------------------------------------------------------*/ 1220 1221 /* 1222 * Generic HC operations. 1223 */ 1224 1225 /*-------------------------------------------------------------------------*/ 1226 1227 /** 1228 * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue 1229 * @hcd: host controller to which @urb was submitted 1230 * @urb: URB being submitted 1231 * 1232 * Host controller drivers should call this routine in their enqueue() 1233 * method. The HCD's private spinlock must be held and interrupts must 1234 * be disabled. The actions carried out here are required for URB 1235 * submission, as well as for endpoint shutdown and for usb_kill_urb. 1236 * 1237 * Return: 0 for no error, otherwise a negative error code (in which case 1238 * the enqueue() method must fail). If no error occurs but enqueue() fails 1239 * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing 1240 * the private spinlock and returning. 1241 */ 1242 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb) 1243 { 1244 int rc = 0; 1245 1246 spin_lock(&hcd_urb_list_lock); 1247 1248 /* Check that the URB isn't being killed */ 1249 if (unlikely(atomic_read(&urb->reject))) { 1250 rc = -EPERM; 1251 goto done; 1252 } 1253 1254 if (unlikely(!urb->ep->enabled)) { 1255 rc = -ENOENT; 1256 goto done; 1257 } 1258 1259 if (unlikely(!urb->dev->can_submit)) { 1260 rc = -EHOSTUNREACH; 1261 goto done; 1262 } 1263 1264 /* 1265 * Check the host controller's state and add the URB to the 1266 * endpoint's queue. 1267 */ 1268 if (HCD_RH_RUNNING(hcd)) { 1269 urb->unlinked = 0; 1270 list_add_tail(&urb->urb_list, &urb->ep->urb_list); 1271 } else { 1272 rc = -ESHUTDOWN; 1273 goto done; 1274 } 1275 done: 1276 spin_unlock(&hcd_urb_list_lock); 1277 return rc; 1278 } 1279 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep); 1280 1281 /** 1282 * usb_hcd_check_unlink_urb - check whether an URB may be unlinked 1283 * @hcd: host controller to which @urb was submitted 1284 * @urb: URB being checked for unlinkability 1285 * @status: error code to store in @urb if the unlink succeeds 1286 * 1287 * Host controller drivers should call this routine in their dequeue() 1288 * method. The HCD's private spinlock must be held and interrupts must 1289 * be disabled. The actions carried out here are required for making 1290 * sure than an unlink is valid. 1291 * 1292 * Return: 0 for no error, otherwise a negative error code (in which case 1293 * the dequeue() method must fail). The possible error codes are: 1294 * 1295 * -EIDRM: @urb was not submitted or has already completed. 1296 * The completion function may not have been called yet. 1297 * 1298 * -EBUSY: @urb has already been unlinked. 1299 */ 1300 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb, 1301 int status) 1302 { 1303 struct list_head *tmp; 1304 1305 /* insist the urb is still queued */ 1306 list_for_each(tmp, &urb->ep->urb_list) { 1307 if (tmp == &urb->urb_list) 1308 break; 1309 } 1310 if (tmp != &urb->urb_list) 1311 return -EIDRM; 1312 1313 /* Any status except -EINPROGRESS means something already started to 1314 * unlink this URB from the hardware. So there's no more work to do. 1315 */ 1316 if (urb->unlinked) 1317 return -EBUSY; 1318 urb->unlinked = status; 1319 return 0; 1320 } 1321 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb); 1322 1323 /** 1324 * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue 1325 * @hcd: host controller to which @urb was submitted 1326 * @urb: URB being unlinked 1327 * 1328 * Host controller drivers should call this routine before calling 1329 * usb_hcd_giveback_urb(). The HCD's private spinlock must be held and 1330 * interrupts must be disabled. The actions carried out here are required 1331 * for URB completion. 1332 */ 1333 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb) 1334 { 1335 /* clear all state linking urb to this dev (and hcd) */ 1336 spin_lock(&hcd_urb_list_lock); 1337 list_del_init(&urb->urb_list); 1338 spin_unlock(&hcd_urb_list_lock); 1339 } 1340 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep); 1341 1342 /* 1343 * Some usb host controllers can only perform dma using a small SRAM area. 1344 * The usb core itself is however optimized for host controllers that can dma 1345 * using regular system memory - like pci devices doing bus mastering. 1346 * 1347 * To support host controllers with limited dma capabilities we provide dma 1348 * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag. 1349 * For this to work properly the host controller code must first use the 1350 * function dma_declare_coherent_memory() to point out which memory area 1351 * that should be used for dma allocations. 1352 * 1353 * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for 1354 * dma using dma_alloc_coherent() which in turn allocates from the memory 1355 * area pointed out with dma_declare_coherent_memory(). 1356 * 1357 * So, to summarize... 1358 * 1359 * - We need "local" memory, canonical example being 1360 * a small SRAM on a discrete controller being the 1361 * only memory that the controller can read ... 1362 * (a) "normal" kernel memory is no good, and 1363 * (b) there's not enough to share 1364 * 1365 * - The only *portable* hook for such stuff in the 1366 * DMA framework is dma_declare_coherent_memory() 1367 * 1368 * - So we use that, even though the primary requirement 1369 * is that the memory be "local" (hence addressable 1370 * by that device), not "coherent". 1371 * 1372 */ 1373 1374 static int hcd_alloc_coherent(struct usb_bus *bus, 1375 gfp_t mem_flags, dma_addr_t *dma_handle, 1376 void **vaddr_handle, size_t size, 1377 enum dma_data_direction dir) 1378 { 1379 unsigned char *vaddr; 1380 1381 if (*vaddr_handle == NULL) { 1382 WARN_ON_ONCE(1); 1383 return -EFAULT; 1384 } 1385 1386 vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr), 1387 mem_flags, dma_handle); 1388 if (!vaddr) 1389 return -ENOMEM; 1390 1391 /* 1392 * Store the virtual address of the buffer at the end 1393 * of the allocated dma buffer. The size of the buffer 1394 * may be uneven so use unaligned functions instead 1395 * of just rounding up. It makes sense to optimize for 1396 * memory footprint over access speed since the amount 1397 * of memory available for dma may be limited. 1398 */ 1399 put_unaligned((unsigned long)*vaddr_handle, 1400 (unsigned long *)(vaddr + size)); 1401 1402 if (dir == DMA_TO_DEVICE) 1403 memcpy(vaddr, *vaddr_handle, size); 1404 1405 *vaddr_handle = vaddr; 1406 return 0; 1407 } 1408 1409 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle, 1410 void **vaddr_handle, size_t size, 1411 enum dma_data_direction dir) 1412 { 1413 unsigned char *vaddr = *vaddr_handle; 1414 1415 vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size)); 1416 1417 if (dir == DMA_FROM_DEVICE) 1418 memcpy(vaddr, *vaddr_handle, size); 1419 1420 hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle); 1421 1422 *vaddr_handle = vaddr; 1423 *dma_handle = 0; 1424 } 1425 1426 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb) 1427 { 1428 if (IS_ENABLED(CONFIG_HAS_DMA) && 1429 (urb->transfer_flags & URB_SETUP_MAP_SINGLE)) 1430 dma_unmap_single(hcd->self.sysdev, 1431 urb->setup_dma, 1432 sizeof(struct usb_ctrlrequest), 1433 DMA_TO_DEVICE); 1434 else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL) 1435 hcd_free_coherent(urb->dev->bus, 1436 &urb->setup_dma, 1437 (void **) &urb->setup_packet, 1438 sizeof(struct usb_ctrlrequest), 1439 DMA_TO_DEVICE); 1440 1441 /* Make it safe to call this routine more than once */ 1442 urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL); 1443 } 1444 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma); 1445 1446 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) 1447 { 1448 if (hcd->driver->unmap_urb_for_dma) 1449 hcd->driver->unmap_urb_for_dma(hcd, urb); 1450 else 1451 usb_hcd_unmap_urb_for_dma(hcd, urb); 1452 } 1453 1454 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) 1455 { 1456 enum dma_data_direction dir; 1457 1458 usb_hcd_unmap_urb_setup_for_dma(hcd, urb); 1459 1460 dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 1461 if (IS_ENABLED(CONFIG_HAS_DMA) && 1462 (urb->transfer_flags & URB_DMA_MAP_SG)) 1463 dma_unmap_sg(hcd->self.sysdev, 1464 urb->sg, 1465 urb->num_sgs, 1466 dir); 1467 else if (IS_ENABLED(CONFIG_HAS_DMA) && 1468 (urb->transfer_flags & URB_DMA_MAP_PAGE)) 1469 dma_unmap_page(hcd->self.sysdev, 1470 urb->transfer_dma, 1471 urb->transfer_buffer_length, 1472 dir); 1473 else if (IS_ENABLED(CONFIG_HAS_DMA) && 1474 (urb->transfer_flags & URB_DMA_MAP_SINGLE)) 1475 dma_unmap_single(hcd->self.sysdev, 1476 urb->transfer_dma, 1477 urb->transfer_buffer_length, 1478 dir); 1479 else if (urb->transfer_flags & URB_MAP_LOCAL) 1480 hcd_free_coherent(urb->dev->bus, 1481 &urb->transfer_dma, 1482 &urb->transfer_buffer, 1483 urb->transfer_buffer_length, 1484 dir); 1485 1486 /* Make it safe to call this routine more than once */ 1487 urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE | 1488 URB_DMA_MAP_SINGLE | URB_MAP_LOCAL); 1489 } 1490 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma); 1491 1492 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, 1493 gfp_t mem_flags) 1494 { 1495 if (hcd->driver->map_urb_for_dma) 1496 return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags); 1497 else 1498 return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags); 1499 } 1500 1501 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, 1502 gfp_t mem_flags) 1503 { 1504 enum dma_data_direction dir; 1505 int ret = 0; 1506 1507 /* Map the URB's buffers for DMA access. 1508 * Lower level HCD code should use *_dma exclusively, 1509 * unless it uses pio or talks to another transport, 1510 * or uses the provided scatter gather list for bulk. 1511 */ 1512 1513 if (usb_endpoint_xfer_control(&urb->ep->desc)) { 1514 if (hcd->self.uses_pio_for_control) 1515 return ret; 1516 if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) { 1517 if (is_vmalloc_addr(urb->setup_packet)) { 1518 WARN_ONCE(1, "setup packet is not dma capable\n"); 1519 return -EAGAIN; 1520 } else if (object_is_on_stack(urb->setup_packet)) { 1521 WARN_ONCE(1, "setup packet is on stack\n"); 1522 return -EAGAIN; 1523 } 1524 1525 urb->setup_dma = dma_map_single( 1526 hcd->self.sysdev, 1527 urb->setup_packet, 1528 sizeof(struct usb_ctrlrequest), 1529 DMA_TO_DEVICE); 1530 if (dma_mapping_error(hcd->self.sysdev, 1531 urb->setup_dma)) 1532 return -EAGAIN; 1533 urb->transfer_flags |= URB_SETUP_MAP_SINGLE; 1534 } else if (hcd->driver->flags & HCD_LOCAL_MEM) { 1535 ret = hcd_alloc_coherent( 1536 urb->dev->bus, mem_flags, 1537 &urb->setup_dma, 1538 (void **)&urb->setup_packet, 1539 sizeof(struct usb_ctrlrequest), 1540 DMA_TO_DEVICE); 1541 if (ret) 1542 return ret; 1543 urb->transfer_flags |= URB_SETUP_MAP_LOCAL; 1544 } 1545 } 1546 1547 dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 1548 if (urb->transfer_buffer_length != 0 1549 && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) { 1550 if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) { 1551 if (urb->num_sgs) { 1552 int n; 1553 1554 /* We don't support sg for isoc transfers ! */ 1555 if (usb_endpoint_xfer_isoc(&urb->ep->desc)) { 1556 WARN_ON(1); 1557 return -EINVAL; 1558 } 1559 1560 n = dma_map_sg( 1561 hcd->self.sysdev, 1562 urb->sg, 1563 urb->num_sgs, 1564 dir); 1565 if (n <= 0) 1566 ret = -EAGAIN; 1567 else 1568 urb->transfer_flags |= URB_DMA_MAP_SG; 1569 urb->num_mapped_sgs = n; 1570 if (n != urb->num_sgs) 1571 urb->transfer_flags |= 1572 URB_DMA_SG_COMBINED; 1573 } else if (urb->sg) { 1574 struct scatterlist *sg = urb->sg; 1575 urb->transfer_dma = dma_map_page( 1576 hcd->self.sysdev, 1577 sg_page(sg), 1578 sg->offset, 1579 urb->transfer_buffer_length, 1580 dir); 1581 if (dma_mapping_error(hcd->self.sysdev, 1582 urb->transfer_dma)) 1583 ret = -EAGAIN; 1584 else 1585 urb->transfer_flags |= URB_DMA_MAP_PAGE; 1586 } else if (is_vmalloc_addr(urb->transfer_buffer)) { 1587 WARN_ONCE(1, "transfer buffer not dma capable\n"); 1588 ret = -EAGAIN; 1589 } else if (object_is_on_stack(urb->transfer_buffer)) { 1590 WARN_ONCE(1, "transfer buffer is on stack\n"); 1591 ret = -EAGAIN; 1592 } else { 1593 urb->transfer_dma = dma_map_single( 1594 hcd->self.sysdev, 1595 urb->transfer_buffer, 1596 urb->transfer_buffer_length, 1597 dir); 1598 if (dma_mapping_error(hcd->self.sysdev, 1599 urb->transfer_dma)) 1600 ret = -EAGAIN; 1601 else 1602 urb->transfer_flags |= URB_DMA_MAP_SINGLE; 1603 } 1604 } else if (hcd->driver->flags & HCD_LOCAL_MEM) { 1605 ret = hcd_alloc_coherent( 1606 urb->dev->bus, mem_flags, 1607 &urb->transfer_dma, 1608 &urb->transfer_buffer, 1609 urb->transfer_buffer_length, 1610 dir); 1611 if (ret == 0) 1612 urb->transfer_flags |= URB_MAP_LOCAL; 1613 } 1614 if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE | 1615 URB_SETUP_MAP_LOCAL))) 1616 usb_hcd_unmap_urb_for_dma(hcd, urb); 1617 } 1618 return ret; 1619 } 1620 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma); 1621 1622 /*-------------------------------------------------------------------------*/ 1623 1624 /* may be called in any context with a valid urb->dev usecount 1625 * caller surrenders "ownership" of urb 1626 * expects usb_submit_urb() to have sanity checked and conditioned all 1627 * inputs in the urb 1628 */ 1629 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags) 1630 { 1631 int status; 1632 struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); 1633 1634 /* increment urb's reference count as part of giving it to the HCD 1635 * (which will control it). HCD guarantees that it either returns 1636 * an error or calls giveback(), but not both. 1637 */ 1638 usb_get_urb(urb); 1639 atomic_inc(&urb->use_count); 1640 atomic_inc(&urb->dev->urbnum); 1641 usbmon_urb_submit(&hcd->self, urb); 1642 1643 /* NOTE requirements on root-hub callers (usbfs and the hub 1644 * driver, for now): URBs' urb->transfer_buffer must be 1645 * valid and usb_buffer_{sync,unmap}() not be needed, since 1646 * they could clobber root hub response data. Also, control 1647 * URBs must be submitted in process context with interrupts 1648 * enabled. 1649 */ 1650 1651 if (is_root_hub(urb->dev)) { 1652 status = rh_urb_enqueue(hcd, urb); 1653 } else { 1654 status = map_urb_for_dma(hcd, urb, mem_flags); 1655 if (likely(status == 0)) { 1656 status = hcd->driver->urb_enqueue(hcd, urb, mem_flags); 1657 if (unlikely(status)) 1658 unmap_urb_for_dma(hcd, urb); 1659 } 1660 } 1661 1662 if (unlikely(status)) { 1663 usbmon_urb_submit_error(&hcd->self, urb, status); 1664 urb->hcpriv = NULL; 1665 INIT_LIST_HEAD(&urb->urb_list); 1666 atomic_dec(&urb->use_count); 1667 atomic_dec(&urb->dev->urbnum); 1668 if (atomic_read(&urb->reject)) 1669 wake_up(&usb_kill_urb_queue); 1670 usb_put_urb(urb); 1671 } 1672 return status; 1673 } 1674 1675 /*-------------------------------------------------------------------------*/ 1676 1677 /* this makes the hcd giveback() the urb more quickly, by kicking it 1678 * off hardware queues (which may take a while) and returning it as 1679 * soon as practical. we've already set up the urb's return status, 1680 * but we can't know if the callback completed already. 1681 */ 1682 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status) 1683 { 1684 int value; 1685 1686 if (is_root_hub(urb->dev)) 1687 value = usb_rh_urb_dequeue(hcd, urb, status); 1688 else { 1689 1690 /* The only reason an HCD might fail this call is if 1691 * it has not yet fully queued the urb to begin with. 1692 * Such failures should be harmless. */ 1693 value = hcd->driver->urb_dequeue(hcd, urb, status); 1694 } 1695 return value; 1696 } 1697 1698 /* 1699 * called in any context 1700 * 1701 * caller guarantees urb won't be recycled till both unlink() 1702 * and the urb's completion function return 1703 */ 1704 int usb_hcd_unlink_urb (struct urb *urb, int status) 1705 { 1706 struct usb_hcd *hcd; 1707 struct usb_device *udev = urb->dev; 1708 int retval = -EIDRM; 1709 unsigned long flags; 1710 1711 /* Prevent the device and bus from going away while 1712 * the unlink is carried out. If they are already gone 1713 * then urb->use_count must be 0, since disconnected 1714 * devices can't have any active URBs. 1715 */ 1716 spin_lock_irqsave(&hcd_urb_unlink_lock, flags); 1717 if (atomic_read(&urb->use_count) > 0) { 1718 retval = 0; 1719 usb_get_dev(udev); 1720 } 1721 spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags); 1722 if (retval == 0) { 1723 hcd = bus_to_hcd(urb->dev->bus); 1724 retval = unlink1(hcd, urb, status); 1725 if (retval == 0) 1726 retval = -EINPROGRESS; 1727 else if (retval != -EIDRM && retval != -EBUSY) 1728 dev_dbg(&udev->dev, "hcd_unlink_urb %pK fail %d\n", 1729 urb, retval); 1730 usb_put_dev(udev); 1731 } 1732 return retval; 1733 } 1734 1735 /*-------------------------------------------------------------------------*/ 1736 1737 static void __usb_hcd_giveback_urb(struct urb *urb) 1738 { 1739 struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); 1740 struct usb_anchor *anchor = urb->anchor; 1741 int status = urb->unlinked; 1742 1743 urb->hcpriv = NULL; 1744 if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) && 1745 urb->actual_length < urb->transfer_buffer_length && 1746 !status)) 1747 status = -EREMOTEIO; 1748 1749 unmap_urb_for_dma(hcd, urb); 1750 usbmon_urb_complete(&hcd->self, urb, status); 1751 usb_anchor_suspend_wakeups(anchor); 1752 usb_unanchor_urb(urb); 1753 if (likely(status == 0)) 1754 usb_led_activity(USB_LED_EVENT_HOST); 1755 1756 /* pass ownership to the completion handler */ 1757 urb->status = status; 1758 urb->complete(urb); 1759 1760 usb_anchor_resume_wakeups(anchor); 1761 atomic_dec(&urb->use_count); 1762 if (unlikely(atomic_read(&urb->reject))) 1763 wake_up(&usb_kill_urb_queue); 1764 usb_put_urb(urb); 1765 } 1766 1767 static void usb_giveback_urb_bh(unsigned long param) 1768 { 1769 struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param; 1770 struct list_head local_list; 1771 1772 spin_lock_irq(&bh->lock); 1773 bh->running = true; 1774 restart: 1775 list_replace_init(&bh->head, &local_list); 1776 spin_unlock_irq(&bh->lock); 1777 1778 while (!list_empty(&local_list)) { 1779 struct urb *urb; 1780 1781 urb = list_entry(local_list.next, struct urb, urb_list); 1782 list_del_init(&urb->urb_list); 1783 bh->completing_ep = urb->ep; 1784 __usb_hcd_giveback_urb(urb); 1785 bh->completing_ep = NULL; 1786 } 1787 1788 /* check if there are new URBs to giveback */ 1789 spin_lock_irq(&bh->lock); 1790 if (!list_empty(&bh->head)) 1791 goto restart; 1792 bh->running = false; 1793 spin_unlock_irq(&bh->lock); 1794 } 1795 1796 /** 1797 * usb_hcd_giveback_urb - return URB from HCD to device driver 1798 * @hcd: host controller returning the URB 1799 * @urb: urb being returned to the USB device driver. 1800 * @status: completion status code for the URB. 1801 * Context: in_interrupt() 1802 * 1803 * This hands the URB from HCD to its USB device driver, using its 1804 * completion function. The HCD has freed all per-urb resources 1805 * (and is done using urb->hcpriv). It also released all HCD locks; 1806 * the device driver won't cause problems if it frees, modifies, 1807 * or resubmits this URB. 1808 * 1809 * If @urb was unlinked, the value of @status will be overridden by 1810 * @urb->unlinked. Erroneous short transfers are detected in case 1811 * the HCD hasn't checked for them. 1812 */ 1813 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status) 1814 { 1815 struct giveback_urb_bh *bh; 1816 bool running, high_prio_bh; 1817 1818 /* pass status to tasklet via unlinked */ 1819 if (likely(!urb->unlinked)) 1820 urb->unlinked = status; 1821 1822 if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) { 1823 __usb_hcd_giveback_urb(urb); 1824 return; 1825 } 1826 1827 if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) { 1828 bh = &hcd->high_prio_bh; 1829 high_prio_bh = true; 1830 } else { 1831 bh = &hcd->low_prio_bh; 1832 high_prio_bh = false; 1833 } 1834 1835 spin_lock(&bh->lock); 1836 list_add_tail(&urb->urb_list, &bh->head); 1837 running = bh->running; 1838 spin_unlock(&bh->lock); 1839 1840 if (running) 1841 ; 1842 else if (high_prio_bh) 1843 tasklet_hi_schedule(&bh->bh); 1844 else 1845 tasklet_schedule(&bh->bh); 1846 } 1847 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb); 1848 1849 /*-------------------------------------------------------------------------*/ 1850 1851 /* Cancel all URBs pending on this endpoint and wait for the endpoint's 1852 * queue to drain completely. The caller must first insure that no more 1853 * URBs can be submitted for this endpoint. 1854 */ 1855 void usb_hcd_flush_endpoint(struct usb_device *udev, 1856 struct usb_host_endpoint *ep) 1857 { 1858 struct usb_hcd *hcd; 1859 struct urb *urb; 1860 1861 if (!ep) 1862 return; 1863 might_sleep(); 1864 hcd = bus_to_hcd(udev->bus); 1865 1866 /* No more submits can occur */ 1867 spin_lock_irq(&hcd_urb_list_lock); 1868 rescan: 1869 list_for_each_entry_reverse(urb, &ep->urb_list, urb_list) { 1870 int is_in; 1871 1872 if (urb->unlinked) 1873 continue; 1874 usb_get_urb (urb); 1875 is_in = usb_urb_dir_in(urb); 1876 spin_unlock(&hcd_urb_list_lock); 1877 1878 /* kick hcd */ 1879 unlink1(hcd, urb, -ESHUTDOWN); 1880 dev_dbg (hcd->self.controller, 1881 "shutdown urb %pK ep%d%s%s\n", 1882 urb, usb_endpoint_num(&ep->desc), 1883 is_in ? "in" : "out", 1884 ({ char *s; 1885 1886 switch (usb_endpoint_type(&ep->desc)) { 1887 case USB_ENDPOINT_XFER_CONTROL: 1888 s = ""; break; 1889 case USB_ENDPOINT_XFER_BULK: 1890 s = "-bulk"; break; 1891 case USB_ENDPOINT_XFER_INT: 1892 s = "-intr"; break; 1893 default: 1894 s = "-iso"; break; 1895 }; 1896 s; 1897 })); 1898 usb_put_urb (urb); 1899 1900 /* list contents may have changed */ 1901 spin_lock(&hcd_urb_list_lock); 1902 goto rescan; 1903 } 1904 spin_unlock_irq(&hcd_urb_list_lock); 1905 1906 /* Wait until the endpoint queue is completely empty */ 1907 while (!list_empty (&ep->urb_list)) { 1908 spin_lock_irq(&hcd_urb_list_lock); 1909 1910 /* The list may have changed while we acquired the spinlock */ 1911 urb = NULL; 1912 if (!list_empty (&ep->urb_list)) { 1913 urb = list_entry (ep->urb_list.prev, struct urb, 1914 urb_list); 1915 usb_get_urb (urb); 1916 } 1917 spin_unlock_irq(&hcd_urb_list_lock); 1918 1919 if (urb) { 1920 usb_kill_urb (urb); 1921 usb_put_urb (urb); 1922 } 1923 } 1924 } 1925 1926 /** 1927 * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds 1928 * the bus bandwidth 1929 * @udev: target &usb_device 1930 * @new_config: new configuration to install 1931 * @cur_alt: the current alternate interface setting 1932 * @new_alt: alternate interface setting that is being installed 1933 * 1934 * To change configurations, pass in the new configuration in new_config, 1935 * and pass NULL for cur_alt and new_alt. 1936 * 1937 * To reset a device's configuration (put the device in the ADDRESSED state), 1938 * pass in NULL for new_config, cur_alt, and new_alt. 1939 * 1940 * To change alternate interface settings, pass in NULL for new_config, 1941 * pass in the current alternate interface setting in cur_alt, 1942 * and pass in the new alternate interface setting in new_alt. 1943 * 1944 * Return: An error if the requested bandwidth change exceeds the 1945 * bus bandwidth or host controller internal resources. 1946 */ 1947 int usb_hcd_alloc_bandwidth(struct usb_device *udev, 1948 struct usb_host_config *new_config, 1949 struct usb_host_interface *cur_alt, 1950 struct usb_host_interface *new_alt) 1951 { 1952 int num_intfs, i, j; 1953 struct usb_host_interface *alt = NULL; 1954 int ret = 0; 1955 struct usb_hcd *hcd; 1956 struct usb_host_endpoint *ep; 1957 1958 hcd = bus_to_hcd(udev->bus); 1959 if (!hcd->driver->check_bandwidth) 1960 return 0; 1961 1962 /* Configuration is being removed - set configuration 0 */ 1963 if (!new_config && !cur_alt) { 1964 for (i = 1; i < 16; ++i) { 1965 ep = udev->ep_out[i]; 1966 if (ep) 1967 hcd->driver->drop_endpoint(hcd, udev, ep); 1968 ep = udev->ep_in[i]; 1969 if (ep) 1970 hcd->driver->drop_endpoint(hcd, udev, ep); 1971 } 1972 hcd->driver->check_bandwidth(hcd, udev); 1973 return 0; 1974 } 1975 /* Check if the HCD says there's enough bandwidth. Enable all endpoints 1976 * each interface's alt setting 0 and ask the HCD to check the bandwidth 1977 * of the bus. There will always be bandwidth for endpoint 0, so it's 1978 * ok to exclude it. 1979 */ 1980 if (new_config) { 1981 num_intfs = new_config->desc.bNumInterfaces; 1982 /* Remove endpoints (except endpoint 0, which is always on the 1983 * schedule) from the old config from the schedule 1984 */ 1985 for (i = 1; i < 16; ++i) { 1986 ep = udev->ep_out[i]; 1987 if (ep) { 1988 ret = hcd->driver->drop_endpoint(hcd, udev, ep); 1989 if (ret < 0) 1990 goto reset; 1991 } 1992 ep = udev->ep_in[i]; 1993 if (ep) { 1994 ret = hcd->driver->drop_endpoint(hcd, udev, ep); 1995 if (ret < 0) 1996 goto reset; 1997 } 1998 } 1999 for (i = 0; i < num_intfs; ++i) { 2000 struct usb_host_interface *first_alt; 2001 int iface_num; 2002 2003 first_alt = &new_config->intf_cache[i]->altsetting[0]; 2004 iface_num = first_alt->desc.bInterfaceNumber; 2005 /* Set up endpoints for alternate interface setting 0 */ 2006 alt = usb_find_alt_setting(new_config, iface_num, 0); 2007 if (!alt) 2008 /* No alt setting 0? Pick the first setting. */ 2009 alt = first_alt; 2010 2011 for (j = 0; j < alt->desc.bNumEndpoints; j++) { 2012 ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]); 2013 if (ret < 0) 2014 goto reset; 2015 } 2016 } 2017 } 2018 if (cur_alt && new_alt) { 2019 struct usb_interface *iface = usb_ifnum_to_if(udev, 2020 cur_alt->desc.bInterfaceNumber); 2021 2022 if (!iface) 2023 return -EINVAL; 2024 if (iface->resetting_device) { 2025 /* 2026 * The USB core just reset the device, so the xHCI host 2027 * and the device will think alt setting 0 is installed. 2028 * However, the USB core will pass in the alternate 2029 * setting installed before the reset as cur_alt. Dig 2030 * out the alternate setting 0 structure, or the first 2031 * alternate setting if a broken device doesn't have alt 2032 * setting 0. 2033 */ 2034 cur_alt = usb_altnum_to_altsetting(iface, 0); 2035 if (!cur_alt) 2036 cur_alt = &iface->altsetting[0]; 2037 } 2038 2039 /* Drop all the endpoints in the current alt setting */ 2040 for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) { 2041 ret = hcd->driver->drop_endpoint(hcd, udev, 2042 &cur_alt->endpoint[i]); 2043 if (ret < 0) 2044 goto reset; 2045 } 2046 /* Add all the endpoints in the new alt setting */ 2047 for (i = 0; i < new_alt->desc.bNumEndpoints; i++) { 2048 ret = hcd->driver->add_endpoint(hcd, udev, 2049 &new_alt->endpoint[i]); 2050 if (ret < 0) 2051 goto reset; 2052 } 2053 } 2054 ret = hcd->driver->check_bandwidth(hcd, udev); 2055 reset: 2056 if (ret < 0) 2057 hcd->driver->reset_bandwidth(hcd, udev); 2058 return ret; 2059 } 2060 2061 /* Disables the endpoint: synchronizes with the hcd to make sure all 2062 * endpoint state is gone from hardware. usb_hcd_flush_endpoint() must 2063 * have been called previously. Use for set_configuration, set_interface, 2064 * driver removal, physical disconnect. 2065 * 2066 * example: a qh stored in ep->hcpriv, holding state related to endpoint 2067 * type, maxpacket size, toggle, halt status, and scheduling. 2068 */ 2069 void usb_hcd_disable_endpoint(struct usb_device *udev, 2070 struct usb_host_endpoint *ep) 2071 { 2072 struct usb_hcd *hcd; 2073 2074 might_sleep(); 2075 hcd = bus_to_hcd(udev->bus); 2076 if (hcd->driver->endpoint_disable) 2077 hcd->driver->endpoint_disable(hcd, ep); 2078 } 2079 2080 /** 2081 * usb_hcd_reset_endpoint - reset host endpoint state 2082 * @udev: USB device. 2083 * @ep: the endpoint to reset. 2084 * 2085 * Resets any host endpoint state such as the toggle bit, sequence 2086 * number and current window. 2087 */ 2088 void usb_hcd_reset_endpoint(struct usb_device *udev, 2089 struct usb_host_endpoint *ep) 2090 { 2091 struct usb_hcd *hcd = bus_to_hcd(udev->bus); 2092 2093 if (hcd->driver->endpoint_reset) 2094 hcd->driver->endpoint_reset(hcd, ep); 2095 else { 2096 int epnum = usb_endpoint_num(&ep->desc); 2097 int is_out = usb_endpoint_dir_out(&ep->desc); 2098 int is_control = usb_endpoint_xfer_control(&ep->desc); 2099 2100 usb_settoggle(udev, epnum, is_out, 0); 2101 if (is_control) 2102 usb_settoggle(udev, epnum, !is_out, 0); 2103 } 2104 } 2105 2106 /** 2107 * usb_alloc_streams - allocate bulk endpoint stream IDs. 2108 * @interface: alternate setting that includes all endpoints. 2109 * @eps: array of endpoints that need streams. 2110 * @num_eps: number of endpoints in the array. 2111 * @num_streams: number of streams to allocate. 2112 * @mem_flags: flags hcd should use to allocate memory. 2113 * 2114 * Sets up a group of bulk endpoints to have @num_streams stream IDs available. 2115 * Drivers may queue multiple transfers to different stream IDs, which may 2116 * complete in a different order than they were queued. 2117 * 2118 * Return: On success, the number of allocated streams. On failure, a negative 2119 * error code. 2120 */ 2121 int usb_alloc_streams(struct usb_interface *interface, 2122 struct usb_host_endpoint **eps, unsigned int num_eps, 2123 unsigned int num_streams, gfp_t mem_flags) 2124 { 2125 struct usb_hcd *hcd; 2126 struct usb_device *dev; 2127 int i, ret; 2128 2129 dev = interface_to_usbdev(interface); 2130 hcd = bus_to_hcd(dev->bus); 2131 if (!hcd->driver->alloc_streams || !hcd->driver->free_streams) 2132 return -EINVAL; 2133 if (dev->speed < USB_SPEED_SUPER) 2134 return -EINVAL; 2135 if (dev->state < USB_STATE_CONFIGURED) 2136 return -ENODEV; 2137 2138 for (i = 0; i < num_eps; i++) { 2139 /* Streams only apply to bulk endpoints. */ 2140 if (!usb_endpoint_xfer_bulk(&eps[i]->desc)) 2141 return -EINVAL; 2142 /* Re-alloc is not allowed */ 2143 if (eps[i]->streams) 2144 return -EINVAL; 2145 } 2146 2147 ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps, 2148 num_streams, mem_flags); 2149 if (ret < 0) 2150 return ret; 2151 2152 for (i = 0; i < num_eps; i++) 2153 eps[i]->streams = ret; 2154 2155 return ret; 2156 } 2157 EXPORT_SYMBOL_GPL(usb_alloc_streams); 2158 2159 /** 2160 * usb_free_streams - free bulk endpoint stream IDs. 2161 * @interface: alternate setting that includes all endpoints. 2162 * @eps: array of endpoints to remove streams from. 2163 * @num_eps: number of endpoints in the array. 2164 * @mem_flags: flags hcd should use to allocate memory. 2165 * 2166 * Reverts a group of bulk endpoints back to not using stream IDs. 2167 * Can fail if we are given bad arguments, or HCD is broken. 2168 * 2169 * Return: 0 on success. On failure, a negative error code. 2170 */ 2171 int usb_free_streams(struct usb_interface *interface, 2172 struct usb_host_endpoint **eps, unsigned int num_eps, 2173 gfp_t mem_flags) 2174 { 2175 struct usb_hcd *hcd; 2176 struct usb_device *dev; 2177 int i, ret; 2178 2179 dev = interface_to_usbdev(interface); 2180 hcd = bus_to_hcd(dev->bus); 2181 if (dev->speed < USB_SPEED_SUPER) 2182 return -EINVAL; 2183 2184 /* Double-free is not allowed */ 2185 for (i = 0; i < num_eps; i++) 2186 if (!eps[i] || !eps[i]->streams) 2187 return -EINVAL; 2188 2189 ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags); 2190 if (ret < 0) 2191 return ret; 2192 2193 for (i = 0; i < num_eps; i++) 2194 eps[i]->streams = 0; 2195 2196 return ret; 2197 } 2198 EXPORT_SYMBOL_GPL(usb_free_streams); 2199 2200 /* Protect against drivers that try to unlink URBs after the device 2201 * is gone, by waiting until all unlinks for @udev are finished. 2202 * Since we don't currently track URBs by device, simply wait until 2203 * nothing is running in the locked region of usb_hcd_unlink_urb(). 2204 */ 2205 void usb_hcd_synchronize_unlinks(struct usb_device *udev) 2206 { 2207 spin_lock_irq(&hcd_urb_unlink_lock); 2208 spin_unlock_irq(&hcd_urb_unlink_lock); 2209 } 2210 2211 /*-------------------------------------------------------------------------*/ 2212 2213 /* called in any context */ 2214 int usb_hcd_get_frame_number (struct usb_device *udev) 2215 { 2216 struct usb_hcd *hcd = bus_to_hcd(udev->bus); 2217 2218 if (!HCD_RH_RUNNING(hcd)) 2219 return -ESHUTDOWN; 2220 return hcd->driver->get_frame_number (hcd); 2221 } 2222 2223 /*-------------------------------------------------------------------------*/ 2224 2225 #ifdef CONFIG_PM 2226 2227 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg) 2228 { 2229 struct usb_hcd *hcd = bus_to_hcd(rhdev->bus); 2230 int status; 2231 int old_state = hcd->state; 2232 2233 dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n", 2234 (PMSG_IS_AUTO(msg) ? "auto-" : ""), 2235 rhdev->do_remote_wakeup); 2236 if (HCD_DEAD(hcd)) { 2237 dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend"); 2238 return 0; 2239 } 2240 2241 if (!hcd->driver->bus_suspend) { 2242 status = -ENOENT; 2243 } else { 2244 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2245 hcd->state = HC_STATE_QUIESCING; 2246 status = hcd->driver->bus_suspend(hcd); 2247 } 2248 if (status == 0) { 2249 usb_set_device_state(rhdev, USB_STATE_SUSPENDED); 2250 hcd->state = HC_STATE_SUSPENDED; 2251 2252 if (!PMSG_IS_AUTO(msg)) 2253 usb_phy_roothub_suspend(hcd->self.sysdev, 2254 hcd->phy_roothub); 2255 2256 /* Did we race with a root-hub wakeup event? */ 2257 if (rhdev->do_remote_wakeup) { 2258 char buffer[6]; 2259 2260 status = hcd->driver->hub_status_data(hcd, buffer); 2261 if (status != 0) { 2262 dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n"); 2263 hcd_bus_resume(rhdev, PMSG_AUTO_RESUME); 2264 status = -EBUSY; 2265 } 2266 } 2267 } else { 2268 spin_lock_irq(&hcd_root_hub_lock); 2269 if (!HCD_DEAD(hcd)) { 2270 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2271 hcd->state = old_state; 2272 } 2273 spin_unlock_irq(&hcd_root_hub_lock); 2274 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", 2275 "suspend", status); 2276 } 2277 return status; 2278 } 2279 2280 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) 2281 { 2282 struct usb_hcd *hcd = bus_to_hcd(rhdev->bus); 2283 int status; 2284 int old_state = hcd->state; 2285 2286 dev_dbg(&rhdev->dev, "usb %sresume\n", 2287 (PMSG_IS_AUTO(msg) ? "auto-" : "")); 2288 if (HCD_DEAD(hcd)) { 2289 dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume"); 2290 return 0; 2291 } 2292 2293 if (!PMSG_IS_AUTO(msg)) { 2294 status = usb_phy_roothub_resume(hcd->self.sysdev, 2295 hcd->phy_roothub); 2296 if (status) 2297 return status; 2298 } 2299 2300 if (!hcd->driver->bus_resume) 2301 return -ENOENT; 2302 if (HCD_RH_RUNNING(hcd)) 2303 return 0; 2304 2305 hcd->state = HC_STATE_RESUMING; 2306 status = hcd->driver->bus_resume(hcd); 2307 clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); 2308 if (status == 0) { 2309 struct usb_device *udev; 2310 int port1; 2311 2312 spin_lock_irq(&hcd_root_hub_lock); 2313 if (!HCD_DEAD(hcd)) { 2314 usb_set_device_state(rhdev, rhdev->actconfig 2315 ? USB_STATE_CONFIGURED 2316 : USB_STATE_ADDRESS); 2317 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2318 hcd->state = HC_STATE_RUNNING; 2319 } 2320 spin_unlock_irq(&hcd_root_hub_lock); 2321 2322 /* 2323 * Check whether any of the enabled ports on the root hub are 2324 * unsuspended. If they are then a TRSMRCY delay is needed 2325 * (this is what the USB-2 spec calls a "global resume"). 2326 * Otherwise we can skip the delay. 2327 */ 2328 usb_hub_for_each_child(rhdev, port1, udev) { 2329 if (udev->state != USB_STATE_NOTATTACHED && 2330 !udev->port_is_suspended) { 2331 usleep_range(10000, 11000); /* TRSMRCY */ 2332 break; 2333 } 2334 } 2335 } else { 2336 hcd->state = old_state; 2337 usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub); 2338 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", 2339 "resume", status); 2340 if (status != -ESHUTDOWN) 2341 usb_hc_died(hcd); 2342 } 2343 return status; 2344 } 2345 2346 /* Workqueue routine for root-hub remote wakeup */ 2347 static void hcd_resume_work(struct work_struct *work) 2348 { 2349 struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work); 2350 struct usb_device *udev = hcd->self.root_hub; 2351 2352 usb_remote_wakeup(udev); 2353 } 2354 2355 /** 2356 * usb_hcd_resume_root_hub - called by HCD to resume its root hub 2357 * @hcd: host controller for this root hub 2358 * 2359 * The USB host controller calls this function when its root hub is 2360 * suspended (with the remote wakeup feature enabled) and a remote 2361 * wakeup request is received. The routine submits a workqueue request 2362 * to resume the root hub (that is, manage its downstream ports again). 2363 */ 2364 void usb_hcd_resume_root_hub (struct usb_hcd *hcd) 2365 { 2366 unsigned long flags; 2367 2368 spin_lock_irqsave (&hcd_root_hub_lock, flags); 2369 if (hcd->rh_registered) { 2370 pm_wakeup_event(&hcd->self.root_hub->dev, 0); 2371 set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); 2372 queue_work(pm_wq, &hcd->wakeup_work); 2373 } 2374 spin_unlock_irqrestore (&hcd_root_hub_lock, flags); 2375 } 2376 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub); 2377 2378 #endif /* CONFIG_PM */ 2379 2380 /*-------------------------------------------------------------------------*/ 2381 2382 #ifdef CONFIG_USB_OTG 2383 2384 /** 2385 * usb_bus_start_enum - start immediate enumeration (for OTG) 2386 * @bus: the bus (must use hcd framework) 2387 * @port_num: 1-based number of port; usually bus->otg_port 2388 * Context: in_interrupt() 2389 * 2390 * Starts enumeration, with an immediate reset followed later by 2391 * hub_wq identifying and possibly configuring the device. 2392 * This is needed by OTG controller drivers, where it helps meet 2393 * HNP protocol timing requirements for starting a port reset. 2394 * 2395 * Return: 0 if successful. 2396 */ 2397 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num) 2398 { 2399 struct usb_hcd *hcd; 2400 int status = -EOPNOTSUPP; 2401 2402 /* NOTE: since HNP can't start by grabbing the bus's address0_sem, 2403 * boards with root hubs hooked up to internal devices (instead of 2404 * just the OTG port) may need more attention to resetting... 2405 */ 2406 hcd = bus_to_hcd(bus); 2407 if (port_num && hcd->driver->start_port_reset) 2408 status = hcd->driver->start_port_reset(hcd, port_num); 2409 2410 /* allocate hub_wq shortly after (first) root port reset finishes; 2411 * it may issue others, until at least 50 msecs have passed. 2412 */ 2413 if (status == 0) 2414 mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10)); 2415 return status; 2416 } 2417 EXPORT_SYMBOL_GPL(usb_bus_start_enum); 2418 2419 #endif 2420 2421 /*-------------------------------------------------------------------------*/ 2422 2423 /** 2424 * usb_hcd_irq - hook IRQs to HCD framework (bus glue) 2425 * @irq: the IRQ being raised 2426 * @__hcd: pointer to the HCD whose IRQ is being signaled 2427 * 2428 * If the controller isn't HALTed, calls the driver's irq handler. 2429 * Checks whether the controller is now dead. 2430 * 2431 * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise. 2432 */ 2433 irqreturn_t usb_hcd_irq (int irq, void *__hcd) 2434 { 2435 struct usb_hcd *hcd = __hcd; 2436 irqreturn_t rc; 2437 2438 if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd))) 2439 rc = IRQ_NONE; 2440 else if (hcd->driver->irq(hcd) == IRQ_NONE) 2441 rc = IRQ_NONE; 2442 else 2443 rc = IRQ_HANDLED; 2444 2445 return rc; 2446 } 2447 EXPORT_SYMBOL_GPL(usb_hcd_irq); 2448 2449 /*-------------------------------------------------------------------------*/ 2450 2451 /** 2452 * usb_hc_died - report abnormal shutdown of a host controller (bus glue) 2453 * @hcd: pointer to the HCD representing the controller 2454 * 2455 * This is called by bus glue to report a USB host controller that died 2456 * while operations may still have been pending. It's called automatically 2457 * by the PCI glue, so only glue for non-PCI busses should need to call it. 2458 * 2459 * Only call this function with the primary HCD. 2460 */ 2461 void usb_hc_died (struct usb_hcd *hcd) 2462 { 2463 unsigned long flags; 2464 2465 dev_err (hcd->self.controller, "HC died; cleaning up\n"); 2466 2467 spin_lock_irqsave (&hcd_root_hub_lock, flags); 2468 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2469 set_bit(HCD_FLAG_DEAD, &hcd->flags); 2470 if (hcd->rh_registered) { 2471 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2472 2473 /* make hub_wq clean up old urbs and devices */ 2474 usb_set_device_state (hcd->self.root_hub, 2475 USB_STATE_NOTATTACHED); 2476 usb_kick_hub_wq(hcd->self.root_hub); 2477 } 2478 if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) { 2479 hcd = hcd->shared_hcd; 2480 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2481 set_bit(HCD_FLAG_DEAD, &hcd->flags); 2482 if (hcd->rh_registered) { 2483 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2484 2485 /* make hub_wq clean up old urbs and devices */ 2486 usb_set_device_state(hcd->self.root_hub, 2487 USB_STATE_NOTATTACHED); 2488 usb_kick_hub_wq(hcd->self.root_hub); 2489 } 2490 } 2491 spin_unlock_irqrestore (&hcd_root_hub_lock, flags); 2492 /* Make sure that the other roothub is also deallocated. */ 2493 } 2494 EXPORT_SYMBOL_GPL (usb_hc_died); 2495 2496 /*-------------------------------------------------------------------------*/ 2497 2498 static void init_giveback_urb_bh(struct giveback_urb_bh *bh) 2499 { 2500 2501 spin_lock_init(&bh->lock); 2502 INIT_LIST_HEAD(&bh->head); 2503 tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh); 2504 } 2505 2506 struct usb_hcd *__usb_create_hcd(const struct hc_driver *driver, 2507 struct device *sysdev, struct device *dev, const char *bus_name, 2508 struct usb_hcd *primary_hcd) 2509 { 2510 struct usb_hcd *hcd; 2511 2512 hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL); 2513 if (!hcd) 2514 return NULL; 2515 if (primary_hcd == NULL) { 2516 hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex), 2517 GFP_KERNEL); 2518 if (!hcd->address0_mutex) { 2519 kfree(hcd); 2520 dev_dbg(dev, "hcd address0 mutex alloc failed\n"); 2521 return NULL; 2522 } 2523 mutex_init(hcd->address0_mutex); 2524 hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex), 2525 GFP_KERNEL); 2526 if (!hcd->bandwidth_mutex) { 2527 kfree(hcd->address0_mutex); 2528 kfree(hcd); 2529 dev_dbg(dev, "hcd bandwidth mutex alloc failed\n"); 2530 return NULL; 2531 } 2532 mutex_init(hcd->bandwidth_mutex); 2533 dev_set_drvdata(dev, hcd); 2534 } else { 2535 mutex_lock(&usb_port_peer_mutex); 2536 hcd->address0_mutex = primary_hcd->address0_mutex; 2537 hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex; 2538 hcd->primary_hcd = primary_hcd; 2539 primary_hcd->primary_hcd = primary_hcd; 2540 hcd->shared_hcd = primary_hcd; 2541 primary_hcd->shared_hcd = hcd; 2542 mutex_unlock(&usb_port_peer_mutex); 2543 } 2544 2545 kref_init(&hcd->kref); 2546 2547 usb_bus_init(&hcd->self); 2548 hcd->self.controller = dev; 2549 hcd->self.sysdev = sysdev; 2550 hcd->self.bus_name = bus_name; 2551 hcd->self.uses_dma = (sysdev->dma_mask != NULL); 2552 2553 timer_setup(&hcd->rh_timer, rh_timer_func, 0); 2554 #ifdef CONFIG_PM 2555 INIT_WORK(&hcd->wakeup_work, hcd_resume_work); 2556 #endif 2557 2558 hcd->driver = driver; 2559 hcd->speed = driver->flags & HCD_MASK; 2560 hcd->product_desc = (driver->product_desc) ? driver->product_desc : 2561 "USB Host Controller"; 2562 return hcd; 2563 } 2564 EXPORT_SYMBOL_GPL(__usb_create_hcd); 2565 2566 /** 2567 * usb_create_shared_hcd - create and initialize an HCD structure 2568 * @driver: HC driver that will use this hcd 2569 * @dev: device for this HC, stored in hcd->self.controller 2570 * @bus_name: value to store in hcd->self.bus_name 2571 * @primary_hcd: a pointer to the usb_hcd structure that is sharing the 2572 * PCI device. Only allocate certain resources for the primary HCD 2573 * Context: !in_interrupt() 2574 * 2575 * Allocate a struct usb_hcd, with extra space at the end for the 2576 * HC driver's private data. Initialize the generic members of the 2577 * hcd structure. 2578 * 2579 * Return: On success, a pointer to the created and initialized HCD structure. 2580 * On failure (e.g. if memory is unavailable), %NULL. 2581 */ 2582 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver, 2583 struct device *dev, const char *bus_name, 2584 struct usb_hcd *primary_hcd) 2585 { 2586 return __usb_create_hcd(driver, dev, dev, bus_name, primary_hcd); 2587 } 2588 EXPORT_SYMBOL_GPL(usb_create_shared_hcd); 2589 2590 /** 2591 * usb_create_hcd - create and initialize an HCD structure 2592 * @driver: HC driver that will use this hcd 2593 * @dev: device for this HC, stored in hcd->self.controller 2594 * @bus_name: value to store in hcd->self.bus_name 2595 * Context: !in_interrupt() 2596 * 2597 * Allocate a struct usb_hcd, with extra space at the end for the 2598 * HC driver's private data. Initialize the generic members of the 2599 * hcd structure. 2600 * 2601 * Return: On success, a pointer to the created and initialized HCD 2602 * structure. On failure (e.g. if memory is unavailable), %NULL. 2603 */ 2604 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver, 2605 struct device *dev, const char *bus_name) 2606 { 2607 return __usb_create_hcd(driver, dev, dev, bus_name, NULL); 2608 } 2609 EXPORT_SYMBOL_GPL(usb_create_hcd); 2610 2611 /* 2612 * Roothubs that share one PCI device must also share the bandwidth mutex. 2613 * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is 2614 * deallocated. 2615 * 2616 * Make sure to deallocate the bandwidth_mutex only when the last HCD is 2617 * freed. When hcd_release() is called for either hcd in a peer set, 2618 * invalidate the peer's ->shared_hcd and ->primary_hcd pointers. 2619 */ 2620 static void hcd_release(struct kref *kref) 2621 { 2622 struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref); 2623 2624 mutex_lock(&usb_port_peer_mutex); 2625 if (hcd->shared_hcd) { 2626 struct usb_hcd *peer = hcd->shared_hcd; 2627 2628 peer->shared_hcd = NULL; 2629 peer->primary_hcd = NULL; 2630 } else { 2631 kfree(hcd->address0_mutex); 2632 kfree(hcd->bandwidth_mutex); 2633 } 2634 mutex_unlock(&usb_port_peer_mutex); 2635 kfree(hcd); 2636 } 2637 2638 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd) 2639 { 2640 if (hcd) 2641 kref_get (&hcd->kref); 2642 return hcd; 2643 } 2644 EXPORT_SYMBOL_GPL(usb_get_hcd); 2645 2646 void usb_put_hcd (struct usb_hcd *hcd) 2647 { 2648 if (hcd) 2649 kref_put (&hcd->kref, hcd_release); 2650 } 2651 EXPORT_SYMBOL_GPL(usb_put_hcd); 2652 2653 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd) 2654 { 2655 if (!hcd->primary_hcd) 2656 return 1; 2657 return hcd == hcd->primary_hcd; 2658 } 2659 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd); 2660 2661 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1) 2662 { 2663 if (!hcd->driver->find_raw_port_number) 2664 return port1; 2665 2666 return hcd->driver->find_raw_port_number(hcd, port1); 2667 } 2668 2669 static int usb_hcd_request_irqs(struct usb_hcd *hcd, 2670 unsigned int irqnum, unsigned long irqflags) 2671 { 2672 int retval; 2673 2674 if (hcd->driver->irq) { 2675 2676 snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d", 2677 hcd->driver->description, hcd->self.busnum); 2678 retval = request_irq(irqnum, &usb_hcd_irq, irqflags, 2679 hcd->irq_descr, hcd); 2680 if (retval != 0) { 2681 dev_err(hcd->self.controller, 2682 "request interrupt %d failed\n", 2683 irqnum); 2684 return retval; 2685 } 2686 hcd->irq = irqnum; 2687 dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum, 2688 (hcd->driver->flags & HCD_MEMORY) ? 2689 "io mem" : "io base", 2690 (unsigned long long)hcd->rsrc_start); 2691 } else { 2692 hcd->irq = 0; 2693 if (hcd->rsrc_start) 2694 dev_info(hcd->self.controller, "%s 0x%08llx\n", 2695 (hcd->driver->flags & HCD_MEMORY) ? 2696 "io mem" : "io base", 2697 (unsigned long long)hcd->rsrc_start); 2698 } 2699 return 0; 2700 } 2701 2702 /* 2703 * Before we free this root hub, flush in-flight peering attempts 2704 * and disable peer lookups 2705 */ 2706 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd) 2707 { 2708 struct usb_device *rhdev; 2709 2710 mutex_lock(&usb_port_peer_mutex); 2711 rhdev = hcd->self.root_hub; 2712 hcd->self.root_hub = NULL; 2713 mutex_unlock(&usb_port_peer_mutex); 2714 usb_put_dev(rhdev); 2715 } 2716 2717 /** 2718 * usb_add_hcd - finish generic HCD structure initialization and register 2719 * @hcd: the usb_hcd structure to initialize 2720 * @irqnum: Interrupt line to allocate 2721 * @irqflags: Interrupt type flags 2722 * 2723 * Finish the remaining parts of generic HCD initialization: allocate the 2724 * buffers of consistent memory, register the bus, request the IRQ line, 2725 * and call the driver's reset() and start() routines. 2726 */ 2727 int usb_add_hcd(struct usb_hcd *hcd, 2728 unsigned int irqnum, unsigned long irqflags) 2729 { 2730 int retval; 2731 struct usb_device *rhdev; 2732 2733 if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) { 2734 hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev); 2735 if (IS_ERR(hcd->phy_roothub)) 2736 return PTR_ERR(hcd->phy_roothub); 2737 2738 retval = usb_phy_roothub_init(hcd->phy_roothub); 2739 if (retval) 2740 return retval; 2741 2742 retval = usb_phy_roothub_set_mode(hcd->phy_roothub, 2743 PHY_MODE_USB_HOST_SS); 2744 if (retval) 2745 retval = usb_phy_roothub_set_mode(hcd->phy_roothub, 2746 PHY_MODE_USB_HOST); 2747 if (retval) 2748 goto err_usb_phy_roothub_power_on; 2749 2750 retval = usb_phy_roothub_power_on(hcd->phy_roothub); 2751 if (retval) 2752 goto err_usb_phy_roothub_power_on; 2753 } 2754 2755 dev_info(hcd->self.controller, "%s\n", hcd->product_desc); 2756 2757 switch (authorized_default) { 2758 case USB_AUTHORIZE_NONE: 2759 hcd->dev_policy = USB_DEVICE_AUTHORIZE_NONE; 2760 break; 2761 2762 case USB_AUTHORIZE_ALL: 2763 hcd->dev_policy = USB_DEVICE_AUTHORIZE_ALL; 2764 break; 2765 2766 case USB_AUTHORIZE_INTERNAL: 2767 hcd->dev_policy = USB_DEVICE_AUTHORIZE_INTERNAL; 2768 break; 2769 2770 case USB_AUTHORIZE_WIRED: 2771 default: 2772 hcd->dev_policy = hcd->wireless ? 2773 USB_DEVICE_AUTHORIZE_NONE : USB_DEVICE_AUTHORIZE_ALL; 2774 break; 2775 } 2776 2777 set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); 2778 2779 /* per default all interfaces are authorized */ 2780 set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); 2781 2782 /* HC is in reset state, but accessible. Now do the one-time init, 2783 * bottom up so that hcds can customize the root hubs before hub_wq 2784 * starts talking to them. (Note, bus id is assigned early too.) 2785 */ 2786 retval = hcd_buffer_create(hcd); 2787 if (retval != 0) { 2788 dev_dbg(hcd->self.sysdev, "pool alloc failed\n"); 2789 goto err_create_buf; 2790 } 2791 2792 retval = usb_register_bus(&hcd->self); 2793 if (retval < 0) 2794 goto err_register_bus; 2795 2796 rhdev = usb_alloc_dev(NULL, &hcd->self, 0); 2797 if (rhdev == NULL) { 2798 dev_err(hcd->self.sysdev, "unable to allocate root hub\n"); 2799 retval = -ENOMEM; 2800 goto err_allocate_root_hub; 2801 } 2802 mutex_lock(&usb_port_peer_mutex); 2803 hcd->self.root_hub = rhdev; 2804 mutex_unlock(&usb_port_peer_mutex); 2805 2806 rhdev->rx_lanes = 1; 2807 rhdev->tx_lanes = 1; 2808 2809 switch (hcd->speed) { 2810 case HCD_USB11: 2811 rhdev->speed = USB_SPEED_FULL; 2812 break; 2813 case HCD_USB2: 2814 rhdev->speed = USB_SPEED_HIGH; 2815 break; 2816 case HCD_USB25: 2817 rhdev->speed = USB_SPEED_WIRELESS; 2818 break; 2819 case HCD_USB3: 2820 rhdev->speed = USB_SPEED_SUPER; 2821 break; 2822 case HCD_USB32: 2823 rhdev->rx_lanes = 2; 2824 rhdev->tx_lanes = 2; 2825 /* fall through */ 2826 case HCD_USB31: 2827 rhdev->speed = USB_SPEED_SUPER_PLUS; 2828 break; 2829 default: 2830 retval = -EINVAL; 2831 goto err_set_rh_speed; 2832 } 2833 2834 /* wakeup flag init defaults to "everything works" for root hubs, 2835 * but drivers can override it in reset() if needed, along with 2836 * recording the overall controller's system wakeup capability. 2837 */ 2838 device_set_wakeup_capable(&rhdev->dev, 1); 2839 2840 /* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is 2841 * registered. But since the controller can die at any time, 2842 * let's initialize the flag before touching the hardware. 2843 */ 2844 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2845 2846 /* "reset" is misnamed; its role is now one-time init. the controller 2847 * should already have been reset (and boot firmware kicked off etc). 2848 */ 2849 if (hcd->driver->reset) { 2850 retval = hcd->driver->reset(hcd); 2851 if (retval < 0) { 2852 dev_err(hcd->self.controller, "can't setup: %d\n", 2853 retval); 2854 goto err_hcd_driver_setup; 2855 } 2856 } 2857 hcd->rh_pollable = 1; 2858 2859 /* NOTE: root hub and controller capabilities may not be the same */ 2860 if (device_can_wakeup(hcd->self.controller) 2861 && device_can_wakeup(&hcd->self.root_hub->dev)) 2862 dev_dbg(hcd->self.controller, "supports USB remote wakeup\n"); 2863 2864 /* initialize tasklets */ 2865 init_giveback_urb_bh(&hcd->high_prio_bh); 2866 init_giveback_urb_bh(&hcd->low_prio_bh); 2867 2868 /* enable irqs just before we start the controller, 2869 * if the BIOS provides legacy PCI irqs. 2870 */ 2871 if (usb_hcd_is_primary_hcd(hcd) && irqnum) { 2872 retval = usb_hcd_request_irqs(hcd, irqnum, irqflags); 2873 if (retval) 2874 goto err_request_irq; 2875 } 2876 2877 hcd->state = HC_STATE_RUNNING; 2878 retval = hcd->driver->start(hcd); 2879 if (retval < 0) { 2880 dev_err(hcd->self.controller, "startup error %d\n", retval); 2881 goto err_hcd_driver_start; 2882 } 2883 2884 /* starting here, usbcore will pay attention to this root hub */ 2885 retval = register_root_hub(hcd); 2886 if (retval != 0) 2887 goto err_register_root_hub; 2888 2889 retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group); 2890 if (retval < 0) { 2891 printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n", 2892 retval); 2893 goto error_create_attr_group; 2894 } 2895 if (hcd->uses_new_polling && HCD_POLL_RH(hcd)) 2896 usb_hcd_poll_rh_status(hcd); 2897 2898 return retval; 2899 2900 error_create_attr_group: 2901 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2902 if (HC_IS_RUNNING(hcd->state)) 2903 hcd->state = HC_STATE_QUIESCING; 2904 spin_lock_irq(&hcd_root_hub_lock); 2905 hcd->rh_registered = 0; 2906 spin_unlock_irq(&hcd_root_hub_lock); 2907 2908 #ifdef CONFIG_PM 2909 cancel_work_sync(&hcd->wakeup_work); 2910 #endif 2911 mutex_lock(&usb_bus_idr_lock); 2912 usb_disconnect(&rhdev); /* Sets rhdev to NULL */ 2913 mutex_unlock(&usb_bus_idr_lock); 2914 err_register_root_hub: 2915 hcd->rh_pollable = 0; 2916 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2917 del_timer_sync(&hcd->rh_timer); 2918 hcd->driver->stop(hcd); 2919 hcd->state = HC_STATE_HALT; 2920 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2921 del_timer_sync(&hcd->rh_timer); 2922 err_hcd_driver_start: 2923 if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0) 2924 free_irq(irqnum, hcd); 2925 err_request_irq: 2926 err_hcd_driver_setup: 2927 err_set_rh_speed: 2928 usb_put_invalidate_rhdev(hcd); 2929 err_allocate_root_hub: 2930 usb_deregister_bus(&hcd->self); 2931 err_register_bus: 2932 hcd_buffer_destroy(hcd); 2933 err_create_buf: 2934 usb_phy_roothub_power_off(hcd->phy_roothub); 2935 err_usb_phy_roothub_power_on: 2936 usb_phy_roothub_exit(hcd->phy_roothub); 2937 2938 return retval; 2939 } 2940 EXPORT_SYMBOL_GPL(usb_add_hcd); 2941 2942 /** 2943 * usb_remove_hcd - shutdown processing for generic HCDs 2944 * @hcd: the usb_hcd structure to remove 2945 * Context: !in_interrupt() 2946 * 2947 * Disconnects the root hub, then reverses the effects of usb_add_hcd(), 2948 * invoking the HCD's stop() method. 2949 */ 2950 void usb_remove_hcd(struct usb_hcd *hcd) 2951 { 2952 struct usb_device *rhdev = hcd->self.root_hub; 2953 2954 dev_info(hcd->self.controller, "remove, state %x\n", hcd->state); 2955 2956 usb_get_dev(rhdev); 2957 sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group); 2958 2959 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2960 if (HC_IS_RUNNING (hcd->state)) 2961 hcd->state = HC_STATE_QUIESCING; 2962 2963 dev_dbg(hcd->self.controller, "roothub graceful disconnect\n"); 2964 spin_lock_irq (&hcd_root_hub_lock); 2965 hcd->rh_registered = 0; 2966 spin_unlock_irq (&hcd_root_hub_lock); 2967 2968 #ifdef CONFIG_PM 2969 cancel_work_sync(&hcd->wakeup_work); 2970 #endif 2971 2972 mutex_lock(&usb_bus_idr_lock); 2973 usb_disconnect(&rhdev); /* Sets rhdev to NULL */ 2974 mutex_unlock(&usb_bus_idr_lock); 2975 2976 /* 2977 * tasklet_kill() isn't needed here because: 2978 * - driver's disconnect() called from usb_disconnect() should 2979 * make sure its URBs are completed during the disconnect() 2980 * callback 2981 * 2982 * - it is too late to run complete() here since driver may have 2983 * been removed already now 2984 */ 2985 2986 /* Prevent any more root-hub status calls from the timer. 2987 * The HCD might still restart the timer (if a port status change 2988 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke 2989 * the hub_status_data() callback. 2990 */ 2991 hcd->rh_pollable = 0; 2992 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2993 del_timer_sync(&hcd->rh_timer); 2994 2995 hcd->driver->stop(hcd); 2996 hcd->state = HC_STATE_HALT; 2997 2998 /* In case the HCD restarted the timer, stop it again. */ 2999 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 3000 del_timer_sync(&hcd->rh_timer); 3001 3002 if (usb_hcd_is_primary_hcd(hcd)) { 3003 if (hcd->irq > 0) 3004 free_irq(hcd->irq, hcd); 3005 } 3006 3007 usb_deregister_bus(&hcd->self); 3008 hcd_buffer_destroy(hcd); 3009 3010 usb_phy_roothub_power_off(hcd->phy_roothub); 3011 usb_phy_roothub_exit(hcd->phy_roothub); 3012 3013 usb_put_invalidate_rhdev(hcd); 3014 hcd->flags = 0; 3015 } 3016 EXPORT_SYMBOL_GPL(usb_remove_hcd); 3017 3018 void 3019 usb_hcd_platform_shutdown(struct platform_device *dev) 3020 { 3021 struct usb_hcd *hcd = platform_get_drvdata(dev); 3022 3023 if (hcd->driver->shutdown) 3024 hcd->driver->shutdown(hcd); 3025 } 3026 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown); 3027 3028 /*-------------------------------------------------------------------------*/ 3029 3030 #if IS_ENABLED(CONFIG_USB_MON) 3031 3032 const struct usb_mon_operations *mon_ops; 3033 3034 /* 3035 * The registration is unlocked. 3036 * We do it this way because we do not want to lock in hot paths. 3037 * 3038 * Notice that the code is minimally error-proof. Because usbmon needs 3039 * symbols from usbcore, usbcore gets referenced and cannot be unloaded first. 3040 */ 3041 3042 int usb_mon_register(const struct usb_mon_operations *ops) 3043 { 3044 3045 if (mon_ops) 3046 return -EBUSY; 3047 3048 mon_ops = ops; 3049 mb(); 3050 return 0; 3051 } 3052 EXPORT_SYMBOL_GPL (usb_mon_register); 3053 3054 void usb_mon_deregister (void) 3055 { 3056 3057 if (mon_ops == NULL) { 3058 printk(KERN_ERR "USB: monitor was not registered\n"); 3059 return; 3060 } 3061 mon_ops = NULL; 3062 mb(); 3063 } 3064 EXPORT_SYMBOL_GPL (usb_mon_deregister); 3065 3066 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */ 3067