1 /* 2 * (C) Copyright Linus Torvalds 1999 3 * (C) Copyright Johannes Erdfelt 1999-2001 4 * (C) Copyright Andreas Gal 1999 5 * (C) Copyright Gregory P. Smith 1999 6 * (C) Copyright Deti Fliegl 1999 7 * (C) Copyright Randy Dunlap 2000 8 * (C) Copyright David Brownell 2000-2002 9 * 10 * This program is free software; you can redistribute it and/or modify it 11 * under the terms of the GNU General Public License as published by the 12 * Free Software Foundation; either version 2 of the License, or (at your 13 * option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, but 16 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 17 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 18 * for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software Foundation, 22 * Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 23 */ 24 25 #include <linux/bcd.h> 26 #include <linux/module.h> 27 #include <linux/version.h> 28 #include <linux/kernel.h> 29 #include <linux/slab.h> 30 #include <linux/completion.h> 31 #include <linux/utsname.h> 32 #include <linux/mm.h> 33 #include <asm/io.h> 34 #include <linux/device.h> 35 #include <linux/dma-mapping.h> 36 #include <linux/mutex.h> 37 #include <asm/irq.h> 38 #include <asm/byteorder.h> 39 #include <asm/unaligned.h> 40 #include <linux/platform_device.h> 41 #include <linux/workqueue.h> 42 #include <linux/pm_runtime.h> 43 #include <linux/types.h> 44 45 #include <linux/phy/phy.h> 46 #include <linux/usb.h> 47 #include <linux/usb/hcd.h> 48 #include <linux/usb/phy.h> 49 50 #include "usb.h" 51 52 53 /*-------------------------------------------------------------------------*/ 54 55 /* 56 * USB Host Controller Driver framework 57 * 58 * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing 59 * HCD-specific behaviors/bugs. 60 * 61 * This does error checks, tracks devices and urbs, and delegates to a 62 * "hc_driver" only for code (and data) that really needs to know about 63 * hardware differences. That includes root hub registers, i/o queues, 64 * and so on ... but as little else as possible. 65 * 66 * Shared code includes most of the "root hub" code (these are emulated, 67 * though each HC's hardware works differently) and PCI glue, plus request 68 * tracking overhead. The HCD code should only block on spinlocks or on 69 * hardware handshaking; blocking on software events (such as other kernel 70 * threads releasing resources, or completing actions) is all generic. 71 * 72 * Happens the USB 2.0 spec says this would be invisible inside the "USBD", 73 * and includes mostly a "HCDI" (HCD Interface) along with some APIs used 74 * only by the hub driver ... and that neither should be seen or used by 75 * usb client device drivers. 76 * 77 * Contributors of ideas or unattributed patches include: David Brownell, 78 * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ... 79 * 80 * HISTORY: 81 * 2002-02-21 Pull in most of the usb_bus support from usb.c; some 82 * associated cleanup. "usb_hcd" still != "usb_bus". 83 * 2001-12-12 Initial patch version for Linux 2.5.1 kernel. 84 */ 85 86 /*-------------------------------------------------------------------------*/ 87 88 /* Keep track of which host controller drivers are loaded */ 89 unsigned long usb_hcds_loaded; 90 EXPORT_SYMBOL_GPL(usb_hcds_loaded); 91 92 /* host controllers we manage */ 93 DEFINE_IDR (usb_bus_idr); 94 EXPORT_SYMBOL_GPL (usb_bus_idr); 95 96 /* used when allocating bus numbers */ 97 #define USB_MAXBUS 64 98 99 /* used when updating list of hcds */ 100 DEFINE_MUTEX(usb_bus_idr_lock); /* exported only for usbfs */ 101 EXPORT_SYMBOL_GPL (usb_bus_idr_lock); 102 103 /* used for controlling access to virtual root hubs */ 104 static DEFINE_SPINLOCK(hcd_root_hub_lock); 105 106 /* used when updating an endpoint's URB list */ 107 static DEFINE_SPINLOCK(hcd_urb_list_lock); 108 109 /* used to protect against unlinking URBs after the device is gone */ 110 static DEFINE_SPINLOCK(hcd_urb_unlink_lock); 111 112 /* wait queue for synchronous unlinks */ 113 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue); 114 115 static inline int is_root_hub(struct usb_device *udev) 116 { 117 return (udev->parent == NULL); 118 } 119 120 /*-------------------------------------------------------------------------*/ 121 122 /* 123 * Sharable chunks of root hub code. 124 */ 125 126 /*-------------------------------------------------------------------------*/ 127 #define KERNEL_REL bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff)) 128 #define KERNEL_VER bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff)) 129 130 /* usb 3.1 root hub device descriptor */ 131 static const u8 usb31_rh_dev_descriptor[18] = { 132 0x12, /* __u8 bLength; */ 133 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 134 0x10, 0x03, /* __le16 bcdUSB; v3.1 */ 135 136 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 137 0x00, /* __u8 bDeviceSubClass; */ 138 0x03, /* __u8 bDeviceProtocol; USB 3 hub */ 139 0x09, /* __u8 bMaxPacketSize0; 2^9 = 512 Bytes */ 140 141 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 142 0x03, 0x00, /* __le16 idProduct; device 0x0003 */ 143 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 144 145 0x03, /* __u8 iManufacturer; */ 146 0x02, /* __u8 iProduct; */ 147 0x01, /* __u8 iSerialNumber; */ 148 0x01 /* __u8 bNumConfigurations; */ 149 }; 150 151 /* usb 3.0 root hub device descriptor */ 152 static const u8 usb3_rh_dev_descriptor[18] = { 153 0x12, /* __u8 bLength; */ 154 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 155 0x00, 0x03, /* __le16 bcdUSB; v3.0 */ 156 157 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 158 0x00, /* __u8 bDeviceSubClass; */ 159 0x03, /* __u8 bDeviceProtocol; USB 3.0 hub */ 160 0x09, /* __u8 bMaxPacketSize0; 2^9 = 512 Bytes */ 161 162 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 163 0x03, 0x00, /* __le16 idProduct; device 0x0003 */ 164 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 165 166 0x03, /* __u8 iManufacturer; */ 167 0x02, /* __u8 iProduct; */ 168 0x01, /* __u8 iSerialNumber; */ 169 0x01 /* __u8 bNumConfigurations; */ 170 }; 171 172 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */ 173 static const u8 usb25_rh_dev_descriptor[18] = { 174 0x12, /* __u8 bLength; */ 175 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 176 0x50, 0x02, /* __le16 bcdUSB; v2.5 */ 177 178 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 179 0x00, /* __u8 bDeviceSubClass; */ 180 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */ 181 0xFF, /* __u8 bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */ 182 183 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 184 0x02, 0x00, /* __le16 idProduct; device 0x0002 */ 185 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 186 187 0x03, /* __u8 iManufacturer; */ 188 0x02, /* __u8 iProduct; */ 189 0x01, /* __u8 iSerialNumber; */ 190 0x01 /* __u8 bNumConfigurations; */ 191 }; 192 193 /* usb 2.0 root hub device descriptor */ 194 static const u8 usb2_rh_dev_descriptor[18] = { 195 0x12, /* __u8 bLength; */ 196 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 197 0x00, 0x02, /* __le16 bcdUSB; v2.0 */ 198 199 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 200 0x00, /* __u8 bDeviceSubClass; */ 201 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */ 202 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */ 203 204 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 205 0x02, 0x00, /* __le16 idProduct; device 0x0002 */ 206 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 207 208 0x03, /* __u8 iManufacturer; */ 209 0x02, /* __u8 iProduct; */ 210 0x01, /* __u8 iSerialNumber; */ 211 0x01 /* __u8 bNumConfigurations; */ 212 }; 213 214 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */ 215 216 /* usb 1.1 root hub device descriptor */ 217 static const u8 usb11_rh_dev_descriptor[18] = { 218 0x12, /* __u8 bLength; */ 219 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 220 0x10, 0x01, /* __le16 bcdUSB; v1.1 */ 221 222 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 223 0x00, /* __u8 bDeviceSubClass; */ 224 0x00, /* __u8 bDeviceProtocol; [ low/full speeds only ] */ 225 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */ 226 227 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 228 0x01, 0x00, /* __le16 idProduct; device 0x0001 */ 229 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 230 231 0x03, /* __u8 iManufacturer; */ 232 0x02, /* __u8 iProduct; */ 233 0x01, /* __u8 iSerialNumber; */ 234 0x01 /* __u8 bNumConfigurations; */ 235 }; 236 237 238 /*-------------------------------------------------------------------------*/ 239 240 /* Configuration descriptors for our root hubs */ 241 242 static const u8 fs_rh_config_descriptor[] = { 243 244 /* one configuration */ 245 0x09, /* __u8 bLength; */ 246 USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */ 247 0x19, 0x00, /* __le16 wTotalLength; */ 248 0x01, /* __u8 bNumInterfaces; (1) */ 249 0x01, /* __u8 bConfigurationValue; */ 250 0x00, /* __u8 iConfiguration; */ 251 0xc0, /* __u8 bmAttributes; 252 Bit 7: must be set, 253 6: Self-powered, 254 5: Remote wakeup, 255 4..0: resvd */ 256 0x00, /* __u8 MaxPower; */ 257 258 /* USB 1.1: 259 * USB 2.0, single TT organization (mandatory): 260 * one interface, protocol 0 261 * 262 * USB 2.0, multiple TT organization (optional): 263 * two interfaces, protocols 1 (like single TT) 264 * and 2 (multiple TT mode) ... config is 265 * sometimes settable 266 * NOT IMPLEMENTED 267 */ 268 269 /* one interface */ 270 0x09, /* __u8 if_bLength; */ 271 USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */ 272 0x00, /* __u8 if_bInterfaceNumber; */ 273 0x00, /* __u8 if_bAlternateSetting; */ 274 0x01, /* __u8 if_bNumEndpoints; */ 275 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ 276 0x00, /* __u8 if_bInterfaceSubClass; */ 277 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */ 278 0x00, /* __u8 if_iInterface; */ 279 280 /* one endpoint (status change endpoint) */ 281 0x07, /* __u8 ep_bLength; */ 282 USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 283 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 284 0x03, /* __u8 ep_bmAttributes; Interrupt */ 285 0x02, 0x00, /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */ 286 0xff /* __u8 ep_bInterval; (255ms -- usb 2.0 spec) */ 287 }; 288 289 static const u8 hs_rh_config_descriptor[] = { 290 291 /* one configuration */ 292 0x09, /* __u8 bLength; */ 293 USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */ 294 0x19, 0x00, /* __le16 wTotalLength; */ 295 0x01, /* __u8 bNumInterfaces; (1) */ 296 0x01, /* __u8 bConfigurationValue; */ 297 0x00, /* __u8 iConfiguration; */ 298 0xc0, /* __u8 bmAttributes; 299 Bit 7: must be set, 300 6: Self-powered, 301 5: Remote wakeup, 302 4..0: resvd */ 303 0x00, /* __u8 MaxPower; */ 304 305 /* USB 1.1: 306 * USB 2.0, single TT organization (mandatory): 307 * one interface, protocol 0 308 * 309 * USB 2.0, multiple TT organization (optional): 310 * two interfaces, protocols 1 (like single TT) 311 * and 2 (multiple TT mode) ... config is 312 * sometimes settable 313 * NOT IMPLEMENTED 314 */ 315 316 /* one interface */ 317 0x09, /* __u8 if_bLength; */ 318 USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */ 319 0x00, /* __u8 if_bInterfaceNumber; */ 320 0x00, /* __u8 if_bAlternateSetting; */ 321 0x01, /* __u8 if_bNumEndpoints; */ 322 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ 323 0x00, /* __u8 if_bInterfaceSubClass; */ 324 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */ 325 0x00, /* __u8 if_iInterface; */ 326 327 /* one endpoint (status change endpoint) */ 328 0x07, /* __u8 ep_bLength; */ 329 USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 330 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 331 0x03, /* __u8 ep_bmAttributes; Interrupt */ 332 /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) 333 * see hub.c:hub_configure() for details. */ 334 (USB_MAXCHILDREN + 1 + 7) / 8, 0x00, 335 0x0c /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */ 336 }; 337 338 static const u8 ss_rh_config_descriptor[] = { 339 /* one configuration */ 340 0x09, /* __u8 bLength; */ 341 USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */ 342 0x1f, 0x00, /* __le16 wTotalLength; */ 343 0x01, /* __u8 bNumInterfaces; (1) */ 344 0x01, /* __u8 bConfigurationValue; */ 345 0x00, /* __u8 iConfiguration; */ 346 0xc0, /* __u8 bmAttributes; 347 Bit 7: must be set, 348 6: Self-powered, 349 5: Remote wakeup, 350 4..0: resvd */ 351 0x00, /* __u8 MaxPower; */ 352 353 /* one interface */ 354 0x09, /* __u8 if_bLength; */ 355 USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */ 356 0x00, /* __u8 if_bInterfaceNumber; */ 357 0x00, /* __u8 if_bAlternateSetting; */ 358 0x01, /* __u8 if_bNumEndpoints; */ 359 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ 360 0x00, /* __u8 if_bInterfaceSubClass; */ 361 0x00, /* __u8 if_bInterfaceProtocol; */ 362 0x00, /* __u8 if_iInterface; */ 363 364 /* one endpoint (status change endpoint) */ 365 0x07, /* __u8 ep_bLength; */ 366 USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 367 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 368 0x03, /* __u8 ep_bmAttributes; Interrupt */ 369 /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) 370 * see hub.c:hub_configure() for details. */ 371 (USB_MAXCHILDREN + 1 + 7) / 8, 0x00, 372 0x0c, /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */ 373 374 /* one SuperSpeed endpoint companion descriptor */ 375 0x06, /* __u8 ss_bLength */ 376 USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */ 377 /* Companion */ 378 0x00, /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */ 379 0x00, /* __u8 ss_bmAttributes; 1 packet per service interval */ 380 0x02, 0x00 /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */ 381 }; 382 383 /* authorized_default behaviour: 384 * -1 is authorized for all devices except wireless (old behaviour) 385 * 0 is unauthorized for all devices 386 * 1 is authorized for all devices 387 */ 388 static int authorized_default = -1; 389 module_param(authorized_default, int, S_IRUGO|S_IWUSR); 390 MODULE_PARM_DESC(authorized_default, 391 "Default USB device authorization: 0 is not authorized, 1 is " 392 "authorized, -1 is authorized except for wireless USB (default, " 393 "old behaviour"); 394 /*-------------------------------------------------------------------------*/ 395 396 /** 397 * ascii2desc() - Helper routine for producing UTF-16LE string descriptors 398 * @s: Null-terminated ASCII (actually ISO-8859-1) string 399 * @buf: Buffer for USB string descriptor (header + UTF-16LE) 400 * @len: Length (in bytes; may be odd) of descriptor buffer. 401 * 402 * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len, 403 * whichever is less. 404 * 405 * Note: 406 * USB String descriptors can contain at most 126 characters; input 407 * strings longer than that are truncated. 408 */ 409 static unsigned 410 ascii2desc(char const *s, u8 *buf, unsigned len) 411 { 412 unsigned n, t = 2 + 2*strlen(s); 413 414 if (t > 254) 415 t = 254; /* Longest possible UTF string descriptor */ 416 if (len > t) 417 len = t; 418 419 t += USB_DT_STRING << 8; /* Now t is first 16 bits to store */ 420 421 n = len; 422 while (n--) { 423 *buf++ = t; 424 if (!n--) 425 break; 426 *buf++ = t >> 8; 427 t = (unsigned char)*s++; 428 } 429 return len; 430 } 431 432 /** 433 * rh_string() - provides string descriptors for root hub 434 * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor) 435 * @hcd: the host controller for this root hub 436 * @data: buffer for output packet 437 * @len: length of the provided buffer 438 * 439 * Produces either a manufacturer, product or serial number string for the 440 * virtual root hub device. 441 * 442 * Return: The number of bytes filled in: the length of the descriptor or 443 * of the provided buffer, whichever is less. 444 */ 445 static unsigned 446 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len) 447 { 448 char buf[100]; 449 char const *s; 450 static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04}; 451 452 /* language ids */ 453 switch (id) { 454 case 0: 455 /* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */ 456 /* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */ 457 if (len > 4) 458 len = 4; 459 memcpy(data, langids, len); 460 return len; 461 case 1: 462 /* Serial number */ 463 s = hcd->self.bus_name; 464 break; 465 case 2: 466 /* Product name */ 467 s = hcd->product_desc; 468 break; 469 case 3: 470 /* Manufacturer */ 471 snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname, 472 init_utsname()->release, hcd->driver->description); 473 s = buf; 474 break; 475 default: 476 /* Can't happen; caller guarantees it */ 477 return 0; 478 } 479 480 return ascii2desc(s, data, len); 481 } 482 483 484 /* Root hub control transfers execute synchronously */ 485 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb) 486 { 487 struct usb_ctrlrequest *cmd; 488 u16 typeReq, wValue, wIndex, wLength; 489 u8 *ubuf = urb->transfer_buffer; 490 unsigned len = 0; 491 int status; 492 u8 patch_wakeup = 0; 493 u8 patch_protocol = 0; 494 u16 tbuf_size; 495 u8 *tbuf = NULL; 496 const u8 *bufp; 497 498 might_sleep(); 499 500 spin_lock_irq(&hcd_root_hub_lock); 501 status = usb_hcd_link_urb_to_ep(hcd, urb); 502 spin_unlock_irq(&hcd_root_hub_lock); 503 if (status) 504 return status; 505 urb->hcpriv = hcd; /* Indicate it's queued */ 506 507 cmd = (struct usb_ctrlrequest *) urb->setup_packet; 508 typeReq = (cmd->bRequestType << 8) | cmd->bRequest; 509 wValue = le16_to_cpu (cmd->wValue); 510 wIndex = le16_to_cpu (cmd->wIndex); 511 wLength = le16_to_cpu (cmd->wLength); 512 513 if (wLength > urb->transfer_buffer_length) 514 goto error; 515 516 /* 517 * tbuf should be at least as big as the 518 * USB hub descriptor. 519 */ 520 tbuf_size = max_t(u16, sizeof(struct usb_hub_descriptor), wLength); 521 tbuf = kzalloc(tbuf_size, GFP_KERNEL); 522 if (!tbuf) 523 return -ENOMEM; 524 525 bufp = tbuf; 526 527 528 urb->actual_length = 0; 529 switch (typeReq) { 530 531 /* DEVICE REQUESTS */ 532 533 /* The root hub's remote wakeup enable bit is implemented using 534 * driver model wakeup flags. If this system supports wakeup 535 * through USB, userspace may change the default "allow wakeup" 536 * policy through sysfs or these calls. 537 * 538 * Most root hubs support wakeup from downstream devices, for 539 * runtime power management (disabling USB clocks and reducing 540 * VBUS power usage). However, not all of them do so; silicon, 541 * board, and BIOS bugs here are not uncommon, so these can't 542 * be treated quite like external hubs. 543 * 544 * Likewise, not all root hubs will pass wakeup events upstream, 545 * to wake up the whole system. So don't assume root hub and 546 * controller capabilities are identical. 547 */ 548 549 case DeviceRequest | USB_REQ_GET_STATUS: 550 tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev) 551 << USB_DEVICE_REMOTE_WAKEUP) 552 | (1 << USB_DEVICE_SELF_POWERED); 553 tbuf[1] = 0; 554 len = 2; 555 break; 556 case DeviceOutRequest | USB_REQ_CLEAR_FEATURE: 557 if (wValue == USB_DEVICE_REMOTE_WAKEUP) 558 device_set_wakeup_enable(&hcd->self.root_hub->dev, 0); 559 else 560 goto error; 561 break; 562 case DeviceOutRequest | USB_REQ_SET_FEATURE: 563 if (device_can_wakeup(&hcd->self.root_hub->dev) 564 && wValue == USB_DEVICE_REMOTE_WAKEUP) 565 device_set_wakeup_enable(&hcd->self.root_hub->dev, 1); 566 else 567 goto error; 568 break; 569 case DeviceRequest | USB_REQ_GET_CONFIGURATION: 570 tbuf[0] = 1; 571 len = 1; 572 /* FALLTHROUGH */ 573 case DeviceOutRequest | USB_REQ_SET_CONFIGURATION: 574 break; 575 case DeviceRequest | USB_REQ_GET_DESCRIPTOR: 576 switch (wValue & 0xff00) { 577 case USB_DT_DEVICE << 8: 578 switch (hcd->speed) { 579 case HCD_USB31: 580 bufp = usb31_rh_dev_descriptor; 581 break; 582 case HCD_USB3: 583 bufp = usb3_rh_dev_descriptor; 584 break; 585 case HCD_USB25: 586 bufp = usb25_rh_dev_descriptor; 587 break; 588 case HCD_USB2: 589 bufp = usb2_rh_dev_descriptor; 590 break; 591 case HCD_USB11: 592 bufp = usb11_rh_dev_descriptor; 593 break; 594 default: 595 goto error; 596 } 597 len = 18; 598 if (hcd->has_tt) 599 patch_protocol = 1; 600 break; 601 case USB_DT_CONFIG << 8: 602 switch (hcd->speed) { 603 case HCD_USB31: 604 case HCD_USB3: 605 bufp = ss_rh_config_descriptor; 606 len = sizeof ss_rh_config_descriptor; 607 break; 608 case HCD_USB25: 609 case HCD_USB2: 610 bufp = hs_rh_config_descriptor; 611 len = sizeof hs_rh_config_descriptor; 612 break; 613 case HCD_USB11: 614 bufp = fs_rh_config_descriptor; 615 len = sizeof fs_rh_config_descriptor; 616 break; 617 default: 618 goto error; 619 } 620 if (device_can_wakeup(&hcd->self.root_hub->dev)) 621 patch_wakeup = 1; 622 break; 623 case USB_DT_STRING << 8: 624 if ((wValue & 0xff) < 4) 625 urb->actual_length = rh_string(wValue & 0xff, 626 hcd, ubuf, wLength); 627 else /* unsupported IDs --> "protocol stall" */ 628 goto error; 629 break; 630 case USB_DT_BOS << 8: 631 goto nongeneric; 632 default: 633 goto error; 634 } 635 break; 636 case DeviceRequest | USB_REQ_GET_INTERFACE: 637 tbuf[0] = 0; 638 len = 1; 639 /* FALLTHROUGH */ 640 case DeviceOutRequest | USB_REQ_SET_INTERFACE: 641 break; 642 case DeviceOutRequest | USB_REQ_SET_ADDRESS: 643 /* wValue == urb->dev->devaddr */ 644 dev_dbg (hcd->self.controller, "root hub device address %d\n", 645 wValue); 646 break; 647 648 /* INTERFACE REQUESTS (no defined feature/status flags) */ 649 650 /* ENDPOINT REQUESTS */ 651 652 case EndpointRequest | USB_REQ_GET_STATUS: 653 /* ENDPOINT_HALT flag */ 654 tbuf[0] = 0; 655 tbuf[1] = 0; 656 len = 2; 657 /* FALLTHROUGH */ 658 case EndpointOutRequest | USB_REQ_CLEAR_FEATURE: 659 case EndpointOutRequest | USB_REQ_SET_FEATURE: 660 dev_dbg (hcd->self.controller, "no endpoint features yet\n"); 661 break; 662 663 /* CLASS REQUESTS (and errors) */ 664 665 default: 666 nongeneric: 667 /* non-generic request */ 668 switch (typeReq) { 669 case GetHubStatus: 670 len = 4; 671 break; 672 case GetPortStatus: 673 if (wValue == HUB_PORT_STATUS) 674 len = 4; 675 else 676 /* other port status types return 8 bytes */ 677 len = 8; 678 break; 679 case GetHubDescriptor: 680 len = sizeof (struct usb_hub_descriptor); 681 break; 682 case DeviceRequest | USB_REQ_GET_DESCRIPTOR: 683 /* len is returned by hub_control */ 684 break; 685 } 686 status = hcd->driver->hub_control (hcd, 687 typeReq, wValue, wIndex, 688 tbuf, wLength); 689 690 if (typeReq == GetHubDescriptor) 691 usb_hub_adjust_deviceremovable(hcd->self.root_hub, 692 (struct usb_hub_descriptor *)tbuf); 693 break; 694 error: 695 /* "protocol stall" on error */ 696 status = -EPIPE; 697 } 698 699 if (status < 0) { 700 len = 0; 701 if (status != -EPIPE) { 702 dev_dbg (hcd->self.controller, 703 "CTRL: TypeReq=0x%x val=0x%x " 704 "idx=0x%x len=%d ==> %d\n", 705 typeReq, wValue, wIndex, 706 wLength, status); 707 } 708 } else if (status > 0) { 709 /* hub_control may return the length of data copied. */ 710 len = status; 711 status = 0; 712 } 713 if (len) { 714 if (urb->transfer_buffer_length < len) 715 len = urb->transfer_buffer_length; 716 urb->actual_length = len; 717 /* always USB_DIR_IN, toward host */ 718 memcpy (ubuf, bufp, len); 719 720 /* report whether RH hardware supports remote wakeup */ 721 if (patch_wakeup && 722 len > offsetof (struct usb_config_descriptor, 723 bmAttributes)) 724 ((struct usb_config_descriptor *)ubuf)->bmAttributes 725 |= USB_CONFIG_ATT_WAKEUP; 726 727 /* report whether RH hardware has an integrated TT */ 728 if (patch_protocol && 729 len > offsetof(struct usb_device_descriptor, 730 bDeviceProtocol)) 731 ((struct usb_device_descriptor *) ubuf)-> 732 bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT; 733 } 734 735 kfree(tbuf); 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 (unsigned long _hcd) 800 { 801 usb_hcd_poll_rh_status((struct usb_hcd *) _hcd); 802 } 803 804 /*-------------------------------------------------------------------------*/ 805 806 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb) 807 { 808 int retval; 809 unsigned long flags; 810 unsigned len = 1 + (urb->dev->maxchild / 8); 811 812 spin_lock_irqsave (&hcd_root_hub_lock, flags); 813 if (hcd->status_urb || urb->transfer_buffer_length < len) { 814 dev_dbg (hcd->self.controller, "not queuing rh status urb\n"); 815 retval = -EINVAL; 816 goto done; 817 } 818 819 retval = usb_hcd_link_urb_to_ep(hcd, urb); 820 if (retval) 821 goto done; 822 823 hcd->status_urb = urb; 824 urb->hcpriv = hcd; /* indicate it's queued */ 825 if (!hcd->uses_new_polling) 826 mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4)); 827 828 /* If a status change has already occurred, report it ASAP */ 829 else if (HCD_POLL_PENDING(hcd)) 830 mod_timer(&hcd->rh_timer, jiffies); 831 retval = 0; 832 done: 833 spin_unlock_irqrestore (&hcd_root_hub_lock, flags); 834 return retval; 835 } 836 837 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb) 838 { 839 if (usb_endpoint_xfer_int(&urb->ep->desc)) 840 return rh_queue_status (hcd, urb); 841 if (usb_endpoint_xfer_control(&urb->ep->desc)) 842 return rh_call_control (hcd, urb); 843 return -EINVAL; 844 } 845 846 /*-------------------------------------------------------------------------*/ 847 848 /* Unlinks of root-hub control URBs are legal, but they don't do anything 849 * since these URBs always execute synchronously. 850 */ 851 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status) 852 { 853 unsigned long flags; 854 int rc; 855 856 spin_lock_irqsave(&hcd_root_hub_lock, flags); 857 rc = usb_hcd_check_unlink_urb(hcd, urb, status); 858 if (rc) 859 goto done; 860 861 if (usb_endpoint_num(&urb->ep->desc) == 0) { /* Control URB */ 862 ; /* Do nothing */ 863 864 } else { /* Status URB */ 865 if (!hcd->uses_new_polling) 866 del_timer (&hcd->rh_timer); 867 if (urb == hcd->status_urb) { 868 hcd->status_urb = NULL; 869 usb_hcd_unlink_urb_from_ep(hcd, urb); 870 usb_hcd_giveback_urb(hcd, urb, status); 871 } 872 } 873 done: 874 spin_unlock_irqrestore(&hcd_root_hub_lock, flags); 875 return rc; 876 } 877 878 879 880 /* 881 * Show & store the current value of authorized_default 882 */ 883 static ssize_t authorized_default_show(struct device *dev, 884 struct device_attribute *attr, char *buf) 885 { 886 struct usb_device *rh_usb_dev = to_usb_device(dev); 887 struct usb_bus *usb_bus = rh_usb_dev->bus; 888 struct usb_hcd *hcd; 889 890 hcd = bus_to_hcd(usb_bus); 891 return snprintf(buf, PAGE_SIZE, "%u\n", !!HCD_DEV_AUTHORIZED(hcd)); 892 } 893 894 static ssize_t authorized_default_store(struct device *dev, 895 struct device_attribute *attr, 896 const char *buf, size_t size) 897 { 898 ssize_t result; 899 unsigned val; 900 struct usb_device *rh_usb_dev = to_usb_device(dev); 901 struct usb_bus *usb_bus = rh_usb_dev->bus; 902 struct usb_hcd *hcd; 903 904 hcd = bus_to_hcd(usb_bus); 905 result = sscanf(buf, "%u\n", &val); 906 if (result == 1) { 907 if (val) 908 set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 909 else 910 clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 911 912 result = size; 913 } else { 914 result = -EINVAL; 915 } 916 return result; 917 } 918 static DEVICE_ATTR_RW(authorized_default); 919 920 /* 921 * interface_authorized_default_show - show default authorization status 922 * for USB interfaces 923 * 924 * note: interface_authorized_default is the default value 925 * for initializing the authorized attribute of interfaces 926 */ 927 static ssize_t interface_authorized_default_show(struct device *dev, 928 struct device_attribute *attr, char *buf) 929 { 930 struct usb_device *usb_dev = to_usb_device(dev); 931 struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus); 932 933 return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd)); 934 } 935 936 /* 937 * interface_authorized_default_store - store default authorization status 938 * for USB interfaces 939 * 940 * note: interface_authorized_default is the default value 941 * for initializing the authorized attribute of interfaces 942 */ 943 static ssize_t interface_authorized_default_store(struct device *dev, 944 struct device_attribute *attr, const char *buf, size_t count) 945 { 946 struct usb_device *usb_dev = to_usb_device(dev); 947 struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus); 948 int rc = count; 949 bool val; 950 951 if (strtobool(buf, &val) != 0) 952 return -EINVAL; 953 954 if (val) 955 set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); 956 else 957 clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); 958 959 return rc; 960 } 961 static DEVICE_ATTR_RW(interface_authorized_default); 962 963 /* Group all the USB bus attributes */ 964 static struct attribute *usb_bus_attrs[] = { 965 &dev_attr_authorized_default.attr, 966 &dev_attr_interface_authorized_default.attr, 967 NULL, 968 }; 969 970 static struct attribute_group usb_bus_attr_group = { 971 .name = NULL, /* we want them in the same directory */ 972 .attrs = usb_bus_attrs, 973 }; 974 975 976 977 /*-------------------------------------------------------------------------*/ 978 979 /** 980 * usb_bus_init - shared initialization code 981 * @bus: the bus structure being initialized 982 * 983 * This code is used to initialize a usb_bus structure, memory for which is 984 * separately managed. 985 */ 986 static void usb_bus_init (struct usb_bus *bus) 987 { 988 memset (&bus->devmap, 0, sizeof(struct usb_devmap)); 989 990 bus->devnum_next = 1; 991 992 bus->root_hub = NULL; 993 bus->busnum = -1; 994 bus->bandwidth_allocated = 0; 995 bus->bandwidth_int_reqs = 0; 996 bus->bandwidth_isoc_reqs = 0; 997 mutex_init(&bus->devnum_next_mutex); 998 } 999 1000 /*-------------------------------------------------------------------------*/ 1001 1002 /** 1003 * usb_register_bus - registers the USB host controller with the usb core 1004 * @bus: pointer to the bus to register 1005 * Context: !in_interrupt() 1006 * 1007 * Assigns a bus number, and links the controller into usbcore data 1008 * structures so that it can be seen by scanning the bus list. 1009 * 1010 * Return: 0 if successful. A negative error code otherwise. 1011 */ 1012 static int usb_register_bus(struct usb_bus *bus) 1013 { 1014 int result = -E2BIG; 1015 int busnum; 1016 1017 mutex_lock(&usb_bus_idr_lock); 1018 busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL); 1019 if (busnum < 0) { 1020 pr_err("%s: failed to get bus number\n", usbcore_name); 1021 goto error_find_busnum; 1022 } 1023 bus->busnum = busnum; 1024 mutex_unlock(&usb_bus_idr_lock); 1025 1026 usb_notify_add_bus(bus); 1027 1028 dev_info (bus->controller, "new USB bus registered, assigned bus " 1029 "number %d\n", bus->busnum); 1030 return 0; 1031 1032 error_find_busnum: 1033 mutex_unlock(&usb_bus_idr_lock); 1034 return result; 1035 } 1036 1037 /** 1038 * usb_deregister_bus - deregisters the USB host controller 1039 * @bus: pointer to the bus to deregister 1040 * Context: !in_interrupt() 1041 * 1042 * Recycles the bus number, and unlinks the controller from usbcore data 1043 * structures so that it won't be seen by scanning the bus list. 1044 */ 1045 static void usb_deregister_bus (struct usb_bus *bus) 1046 { 1047 dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum); 1048 1049 /* 1050 * NOTE: make sure that all the devices are removed by the 1051 * controller code, as well as having it call this when cleaning 1052 * itself up 1053 */ 1054 mutex_lock(&usb_bus_idr_lock); 1055 idr_remove(&usb_bus_idr, bus->busnum); 1056 mutex_unlock(&usb_bus_idr_lock); 1057 1058 usb_notify_remove_bus(bus); 1059 } 1060 1061 /** 1062 * register_root_hub - called by usb_add_hcd() to register a root hub 1063 * @hcd: host controller for this root hub 1064 * 1065 * This function registers the root hub with the USB subsystem. It sets up 1066 * the device properly in the device tree and then calls usb_new_device() 1067 * to register the usb device. It also assigns the root hub's USB address 1068 * (always 1). 1069 * 1070 * Return: 0 if successful. A negative error code otherwise. 1071 */ 1072 static int register_root_hub(struct usb_hcd *hcd) 1073 { 1074 struct device *parent_dev = hcd->self.controller; 1075 struct usb_device *usb_dev = hcd->self.root_hub; 1076 const int devnum = 1; 1077 int retval; 1078 1079 usb_dev->devnum = devnum; 1080 usb_dev->bus->devnum_next = devnum + 1; 1081 memset (&usb_dev->bus->devmap.devicemap, 0, 1082 sizeof usb_dev->bus->devmap.devicemap); 1083 set_bit (devnum, usb_dev->bus->devmap.devicemap); 1084 usb_set_device_state(usb_dev, USB_STATE_ADDRESS); 1085 1086 mutex_lock(&usb_bus_idr_lock); 1087 1088 usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64); 1089 retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE); 1090 if (retval != sizeof usb_dev->descriptor) { 1091 mutex_unlock(&usb_bus_idr_lock); 1092 dev_dbg (parent_dev, "can't read %s device descriptor %d\n", 1093 dev_name(&usb_dev->dev), retval); 1094 return (retval < 0) ? retval : -EMSGSIZE; 1095 } 1096 1097 if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) { 1098 retval = usb_get_bos_descriptor(usb_dev); 1099 if (!retval) { 1100 usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev); 1101 } else if (usb_dev->speed >= USB_SPEED_SUPER) { 1102 mutex_unlock(&usb_bus_idr_lock); 1103 dev_dbg(parent_dev, "can't read %s bos descriptor %d\n", 1104 dev_name(&usb_dev->dev), retval); 1105 return retval; 1106 } 1107 } 1108 1109 retval = usb_new_device (usb_dev); 1110 if (retval) { 1111 dev_err (parent_dev, "can't register root hub for %s, %d\n", 1112 dev_name(&usb_dev->dev), retval); 1113 } else { 1114 spin_lock_irq (&hcd_root_hub_lock); 1115 hcd->rh_registered = 1; 1116 spin_unlock_irq (&hcd_root_hub_lock); 1117 1118 /* Did the HC die before the root hub was registered? */ 1119 if (HCD_DEAD(hcd)) 1120 usb_hc_died (hcd); /* This time clean up */ 1121 usb_dev->dev.of_node = parent_dev->of_node; 1122 } 1123 mutex_unlock(&usb_bus_idr_lock); 1124 1125 return retval; 1126 } 1127 1128 /* 1129 * usb_hcd_start_port_resume - a root-hub port is sending a resume signal 1130 * @bus: the bus which the root hub belongs to 1131 * @portnum: the port which is being resumed 1132 * 1133 * HCDs should call this function when they know that a resume signal is 1134 * being sent to a root-hub port. The root hub will be prevented from 1135 * going into autosuspend until usb_hcd_end_port_resume() is called. 1136 * 1137 * The bus's private lock must be held by the caller. 1138 */ 1139 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum) 1140 { 1141 unsigned bit = 1 << portnum; 1142 1143 if (!(bus->resuming_ports & bit)) { 1144 bus->resuming_ports |= bit; 1145 pm_runtime_get_noresume(&bus->root_hub->dev); 1146 } 1147 } 1148 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume); 1149 1150 /* 1151 * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal 1152 * @bus: the bus which the root hub belongs to 1153 * @portnum: the port which is being resumed 1154 * 1155 * HCDs should call this function when they know that a resume signal has 1156 * stopped being sent to a root-hub port. The root hub will be allowed to 1157 * autosuspend again. 1158 * 1159 * The bus's private lock must be held by the caller. 1160 */ 1161 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum) 1162 { 1163 unsigned bit = 1 << portnum; 1164 1165 if (bus->resuming_ports & bit) { 1166 bus->resuming_ports &= ~bit; 1167 pm_runtime_put_noidle(&bus->root_hub->dev); 1168 } 1169 } 1170 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume); 1171 1172 /*-------------------------------------------------------------------------*/ 1173 1174 /** 1175 * usb_calc_bus_time - approximate periodic transaction time in nanoseconds 1176 * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH} 1177 * @is_input: true iff the transaction sends data to the host 1178 * @isoc: true for isochronous transactions, false for interrupt ones 1179 * @bytecount: how many bytes in the transaction. 1180 * 1181 * Return: Approximate bus time in nanoseconds for a periodic transaction. 1182 * 1183 * Note: 1184 * See USB 2.0 spec section 5.11.3; only periodic transfers need to be 1185 * scheduled in software, this function is only used for such scheduling. 1186 */ 1187 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount) 1188 { 1189 unsigned long tmp; 1190 1191 switch (speed) { 1192 case USB_SPEED_LOW: /* INTR only */ 1193 if (is_input) { 1194 tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L; 1195 return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp; 1196 } else { 1197 tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L; 1198 return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp; 1199 } 1200 case USB_SPEED_FULL: /* ISOC or INTR */ 1201 if (isoc) { 1202 tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L; 1203 return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp; 1204 } else { 1205 tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L; 1206 return 9107L + BW_HOST_DELAY + tmp; 1207 } 1208 case USB_SPEED_HIGH: /* ISOC or INTR */ 1209 /* FIXME adjust for input vs output */ 1210 if (isoc) 1211 tmp = HS_NSECS_ISO (bytecount); 1212 else 1213 tmp = HS_NSECS (bytecount); 1214 return tmp; 1215 default: 1216 pr_debug ("%s: bogus device speed!\n", usbcore_name); 1217 return -1; 1218 } 1219 } 1220 EXPORT_SYMBOL_GPL(usb_calc_bus_time); 1221 1222 1223 /*-------------------------------------------------------------------------*/ 1224 1225 /* 1226 * Generic HC operations. 1227 */ 1228 1229 /*-------------------------------------------------------------------------*/ 1230 1231 /** 1232 * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue 1233 * @hcd: host controller to which @urb was submitted 1234 * @urb: URB being submitted 1235 * 1236 * Host controller drivers should call this routine in their enqueue() 1237 * method. The HCD's private spinlock must be held and interrupts must 1238 * be disabled. The actions carried out here are required for URB 1239 * submission, as well as for endpoint shutdown and for usb_kill_urb. 1240 * 1241 * Return: 0 for no error, otherwise a negative error code (in which case 1242 * the enqueue() method must fail). If no error occurs but enqueue() fails 1243 * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing 1244 * the private spinlock and returning. 1245 */ 1246 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb) 1247 { 1248 int rc = 0; 1249 1250 spin_lock(&hcd_urb_list_lock); 1251 1252 /* Check that the URB isn't being killed */ 1253 if (unlikely(atomic_read(&urb->reject))) { 1254 rc = -EPERM; 1255 goto done; 1256 } 1257 1258 if (unlikely(!urb->ep->enabled)) { 1259 rc = -ENOENT; 1260 goto done; 1261 } 1262 1263 if (unlikely(!urb->dev->can_submit)) { 1264 rc = -EHOSTUNREACH; 1265 goto done; 1266 } 1267 1268 /* 1269 * Check the host controller's state and add the URB to the 1270 * endpoint's queue. 1271 */ 1272 if (HCD_RH_RUNNING(hcd)) { 1273 urb->unlinked = 0; 1274 list_add_tail(&urb->urb_list, &urb->ep->urb_list); 1275 } else { 1276 rc = -ESHUTDOWN; 1277 goto done; 1278 } 1279 done: 1280 spin_unlock(&hcd_urb_list_lock); 1281 return rc; 1282 } 1283 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep); 1284 1285 /** 1286 * usb_hcd_check_unlink_urb - check whether an URB may be unlinked 1287 * @hcd: host controller to which @urb was submitted 1288 * @urb: URB being checked for unlinkability 1289 * @status: error code to store in @urb if the unlink succeeds 1290 * 1291 * Host controller drivers should call this routine in their dequeue() 1292 * method. The HCD's private spinlock must be held and interrupts must 1293 * be disabled. The actions carried out here are required for making 1294 * sure than an unlink is valid. 1295 * 1296 * Return: 0 for no error, otherwise a negative error code (in which case 1297 * the dequeue() method must fail). The possible error codes are: 1298 * 1299 * -EIDRM: @urb was not submitted or has already completed. 1300 * The completion function may not have been called yet. 1301 * 1302 * -EBUSY: @urb has already been unlinked. 1303 */ 1304 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb, 1305 int status) 1306 { 1307 struct list_head *tmp; 1308 1309 /* insist the urb is still queued */ 1310 list_for_each(tmp, &urb->ep->urb_list) { 1311 if (tmp == &urb->urb_list) 1312 break; 1313 } 1314 if (tmp != &urb->urb_list) 1315 return -EIDRM; 1316 1317 /* Any status except -EINPROGRESS means something already started to 1318 * unlink this URB from the hardware. So there's no more work to do. 1319 */ 1320 if (urb->unlinked) 1321 return -EBUSY; 1322 urb->unlinked = status; 1323 return 0; 1324 } 1325 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb); 1326 1327 /** 1328 * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue 1329 * @hcd: host controller to which @urb was submitted 1330 * @urb: URB being unlinked 1331 * 1332 * Host controller drivers should call this routine before calling 1333 * usb_hcd_giveback_urb(). The HCD's private spinlock must be held and 1334 * interrupts must be disabled. The actions carried out here are required 1335 * for URB completion. 1336 */ 1337 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb) 1338 { 1339 /* clear all state linking urb to this dev (and hcd) */ 1340 spin_lock(&hcd_urb_list_lock); 1341 list_del_init(&urb->urb_list); 1342 spin_unlock(&hcd_urb_list_lock); 1343 } 1344 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep); 1345 1346 /* 1347 * Some usb host controllers can only perform dma using a small SRAM area. 1348 * The usb core itself is however optimized for host controllers that can dma 1349 * using regular system memory - like pci devices doing bus mastering. 1350 * 1351 * To support host controllers with limited dma capabilities we provide dma 1352 * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag. 1353 * For this to work properly the host controller code must first use the 1354 * function dma_declare_coherent_memory() to point out which memory area 1355 * that should be used for dma allocations. 1356 * 1357 * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for 1358 * dma using dma_alloc_coherent() which in turn allocates from the memory 1359 * area pointed out with dma_declare_coherent_memory(). 1360 * 1361 * So, to summarize... 1362 * 1363 * - We need "local" memory, canonical example being 1364 * a small SRAM on a discrete controller being the 1365 * only memory that the controller can read ... 1366 * (a) "normal" kernel memory is no good, and 1367 * (b) there's not enough to share 1368 * 1369 * - The only *portable* hook for such stuff in the 1370 * DMA framework is dma_declare_coherent_memory() 1371 * 1372 * - So we use that, even though the primary requirement 1373 * is that the memory be "local" (hence addressable 1374 * by that device), not "coherent". 1375 * 1376 */ 1377 1378 static int hcd_alloc_coherent(struct usb_bus *bus, 1379 gfp_t mem_flags, dma_addr_t *dma_handle, 1380 void **vaddr_handle, size_t size, 1381 enum dma_data_direction dir) 1382 { 1383 unsigned char *vaddr; 1384 1385 if (*vaddr_handle == NULL) { 1386 WARN_ON_ONCE(1); 1387 return -EFAULT; 1388 } 1389 1390 vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr), 1391 mem_flags, dma_handle); 1392 if (!vaddr) 1393 return -ENOMEM; 1394 1395 /* 1396 * Store the virtual address of the buffer at the end 1397 * of the allocated dma buffer. The size of the buffer 1398 * may be uneven so use unaligned functions instead 1399 * of just rounding up. It makes sense to optimize for 1400 * memory footprint over access speed since the amount 1401 * of memory available for dma may be limited. 1402 */ 1403 put_unaligned((unsigned long)*vaddr_handle, 1404 (unsigned long *)(vaddr + size)); 1405 1406 if (dir == DMA_TO_DEVICE) 1407 memcpy(vaddr, *vaddr_handle, size); 1408 1409 *vaddr_handle = vaddr; 1410 return 0; 1411 } 1412 1413 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle, 1414 void **vaddr_handle, size_t size, 1415 enum dma_data_direction dir) 1416 { 1417 unsigned char *vaddr = *vaddr_handle; 1418 1419 vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size)); 1420 1421 if (dir == DMA_FROM_DEVICE) 1422 memcpy(vaddr, *vaddr_handle, size); 1423 1424 hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle); 1425 1426 *vaddr_handle = vaddr; 1427 *dma_handle = 0; 1428 } 1429 1430 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb) 1431 { 1432 if (IS_ENABLED(CONFIG_HAS_DMA) && 1433 (urb->transfer_flags & URB_SETUP_MAP_SINGLE)) 1434 dma_unmap_single(hcd->self.controller, 1435 urb->setup_dma, 1436 sizeof(struct usb_ctrlrequest), 1437 DMA_TO_DEVICE); 1438 else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL) 1439 hcd_free_coherent(urb->dev->bus, 1440 &urb->setup_dma, 1441 (void **) &urb->setup_packet, 1442 sizeof(struct usb_ctrlrequest), 1443 DMA_TO_DEVICE); 1444 1445 /* Make it safe to call this routine more than once */ 1446 urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL); 1447 } 1448 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma); 1449 1450 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) 1451 { 1452 if (hcd->driver->unmap_urb_for_dma) 1453 hcd->driver->unmap_urb_for_dma(hcd, urb); 1454 else 1455 usb_hcd_unmap_urb_for_dma(hcd, urb); 1456 } 1457 1458 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) 1459 { 1460 enum dma_data_direction dir; 1461 1462 usb_hcd_unmap_urb_setup_for_dma(hcd, urb); 1463 1464 dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 1465 if (IS_ENABLED(CONFIG_HAS_DMA) && 1466 (urb->transfer_flags & URB_DMA_MAP_SG)) 1467 dma_unmap_sg(hcd->self.controller, 1468 urb->sg, 1469 urb->num_sgs, 1470 dir); 1471 else if (IS_ENABLED(CONFIG_HAS_DMA) && 1472 (urb->transfer_flags & URB_DMA_MAP_PAGE)) 1473 dma_unmap_page(hcd->self.controller, 1474 urb->transfer_dma, 1475 urb->transfer_buffer_length, 1476 dir); 1477 else if (IS_ENABLED(CONFIG_HAS_DMA) && 1478 (urb->transfer_flags & URB_DMA_MAP_SINGLE)) 1479 dma_unmap_single(hcd->self.controller, 1480 urb->transfer_dma, 1481 urb->transfer_buffer_length, 1482 dir); 1483 else if (urb->transfer_flags & URB_MAP_LOCAL) 1484 hcd_free_coherent(urb->dev->bus, 1485 &urb->transfer_dma, 1486 &urb->transfer_buffer, 1487 urb->transfer_buffer_length, 1488 dir); 1489 1490 /* Make it safe to call this routine more than once */ 1491 urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE | 1492 URB_DMA_MAP_SINGLE | URB_MAP_LOCAL); 1493 } 1494 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma); 1495 1496 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, 1497 gfp_t mem_flags) 1498 { 1499 if (hcd->driver->map_urb_for_dma) 1500 return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags); 1501 else 1502 return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags); 1503 } 1504 1505 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, 1506 gfp_t mem_flags) 1507 { 1508 enum dma_data_direction dir; 1509 int ret = 0; 1510 1511 /* Map the URB's buffers for DMA access. 1512 * Lower level HCD code should use *_dma exclusively, 1513 * unless it uses pio or talks to another transport, 1514 * or uses the provided scatter gather list for bulk. 1515 */ 1516 1517 if (usb_endpoint_xfer_control(&urb->ep->desc)) { 1518 if (hcd->self.uses_pio_for_control) 1519 return ret; 1520 if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) { 1521 urb->setup_dma = dma_map_single( 1522 hcd->self.controller, 1523 urb->setup_packet, 1524 sizeof(struct usb_ctrlrequest), 1525 DMA_TO_DEVICE); 1526 if (dma_mapping_error(hcd->self.controller, 1527 urb->setup_dma)) 1528 return -EAGAIN; 1529 urb->transfer_flags |= URB_SETUP_MAP_SINGLE; 1530 } else if (hcd->driver->flags & HCD_LOCAL_MEM) { 1531 ret = hcd_alloc_coherent( 1532 urb->dev->bus, mem_flags, 1533 &urb->setup_dma, 1534 (void **)&urb->setup_packet, 1535 sizeof(struct usb_ctrlrequest), 1536 DMA_TO_DEVICE); 1537 if (ret) 1538 return ret; 1539 urb->transfer_flags |= URB_SETUP_MAP_LOCAL; 1540 } 1541 } 1542 1543 dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 1544 if (urb->transfer_buffer_length != 0 1545 && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) { 1546 if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) { 1547 if (urb->num_sgs) { 1548 int n; 1549 1550 /* We don't support sg for isoc transfers ! */ 1551 if (usb_endpoint_xfer_isoc(&urb->ep->desc)) { 1552 WARN_ON(1); 1553 return -EINVAL; 1554 } 1555 1556 n = dma_map_sg( 1557 hcd->self.controller, 1558 urb->sg, 1559 urb->num_sgs, 1560 dir); 1561 if (n <= 0) 1562 ret = -EAGAIN; 1563 else 1564 urb->transfer_flags |= URB_DMA_MAP_SG; 1565 urb->num_mapped_sgs = n; 1566 if (n != urb->num_sgs) 1567 urb->transfer_flags |= 1568 URB_DMA_SG_COMBINED; 1569 } else if (urb->sg) { 1570 struct scatterlist *sg = urb->sg; 1571 urb->transfer_dma = dma_map_page( 1572 hcd->self.controller, 1573 sg_page(sg), 1574 sg->offset, 1575 urb->transfer_buffer_length, 1576 dir); 1577 if (dma_mapping_error(hcd->self.controller, 1578 urb->transfer_dma)) 1579 ret = -EAGAIN; 1580 else 1581 urb->transfer_flags |= URB_DMA_MAP_PAGE; 1582 } else if (is_vmalloc_addr(urb->transfer_buffer)) { 1583 WARN_ONCE(1, "transfer buffer not dma capable\n"); 1584 ret = -EAGAIN; 1585 } else { 1586 urb->transfer_dma = dma_map_single( 1587 hcd->self.controller, 1588 urb->transfer_buffer, 1589 urb->transfer_buffer_length, 1590 dir); 1591 if (dma_mapping_error(hcd->self.controller, 1592 urb->transfer_dma)) 1593 ret = -EAGAIN; 1594 else 1595 urb->transfer_flags |= URB_DMA_MAP_SINGLE; 1596 } 1597 } else if (hcd->driver->flags & HCD_LOCAL_MEM) { 1598 ret = hcd_alloc_coherent( 1599 urb->dev->bus, mem_flags, 1600 &urb->transfer_dma, 1601 &urb->transfer_buffer, 1602 urb->transfer_buffer_length, 1603 dir); 1604 if (ret == 0) 1605 urb->transfer_flags |= URB_MAP_LOCAL; 1606 } 1607 if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE | 1608 URB_SETUP_MAP_LOCAL))) 1609 usb_hcd_unmap_urb_for_dma(hcd, urb); 1610 } 1611 return ret; 1612 } 1613 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma); 1614 1615 /*-------------------------------------------------------------------------*/ 1616 1617 /* may be called in any context with a valid urb->dev usecount 1618 * caller surrenders "ownership" of urb 1619 * expects usb_submit_urb() to have sanity checked and conditioned all 1620 * inputs in the urb 1621 */ 1622 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags) 1623 { 1624 int status; 1625 struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); 1626 1627 /* increment urb's reference count as part of giving it to the HCD 1628 * (which will control it). HCD guarantees that it either returns 1629 * an error or calls giveback(), but not both. 1630 */ 1631 usb_get_urb(urb); 1632 atomic_inc(&urb->use_count); 1633 atomic_inc(&urb->dev->urbnum); 1634 usbmon_urb_submit(&hcd->self, urb); 1635 1636 /* NOTE requirements on root-hub callers (usbfs and the hub 1637 * driver, for now): URBs' urb->transfer_buffer must be 1638 * valid and usb_buffer_{sync,unmap}() not be needed, since 1639 * they could clobber root hub response data. Also, control 1640 * URBs must be submitted in process context with interrupts 1641 * enabled. 1642 */ 1643 1644 if (is_root_hub(urb->dev)) { 1645 status = rh_urb_enqueue(hcd, urb); 1646 } else { 1647 status = map_urb_for_dma(hcd, urb, mem_flags); 1648 if (likely(status == 0)) { 1649 status = hcd->driver->urb_enqueue(hcd, urb, mem_flags); 1650 if (unlikely(status)) 1651 unmap_urb_for_dma(hcd, urb); 1652 } 1653 } 1654 1655 if (unlikely(status)) { 1656 usbmon_urb_submit_error(&hcd->self, urb, status); 1657 urb->hcpriv = NULL; 1658 INIT_LIST_HEAD(&urb->urb_list); 1659 atomic_dec(&urb->use_count); 1660 atomic_dec(&urb->dev->urbnum); 1661 if (atomic_read(&urb->reject)) 1662 wake_up(&usb_kill_urb_queue); 1663 usb_put_urb(urb); 1664 } 1665 return status; 1666 } 1667 1668 /*-------------------------------------------------------------------------*/ 1669 1670 /* this makes the hcd giveback() the urb more quickly, by kicking it 1671 * off hardware queues (which may take a while) and returning it as 1672 * soon as practical. we've already set up the urb's return status, 1673 * but we can't know if the callback completed already. 1674 */ 1675 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status) 1676 { 1677 int value; 1678 1679 if (is_root_hub(urb->dev)) 1680 value = usb_rh_urb_dequeue(hcd, urb, status); 1681 else { 1682 1683 /* The only reason an HCD might fail this call is if 1684 * it has not yet fully queued the urb to begin with. 1685 * Such failures should be harmless. */ 1686 value = hcd->driver->urb_dequeue(hcd, urb, status); 1687 } 1688 return value; 1689 } 1690 1691 /* 1692 * called in any context 1693 * 1694 * caller guarantees urb won't be recycled till both unlink() 1695 * and the urb's completion function return 1696 */ 1697 int usb_hcd_unlink_urb (struct urb *urb, int status) 1698 { 1699 struct usb_hcd *hcd; 1700 struct usb_device *udev = urb->dev; 1701 int retval = -EIDRM; 1702 unsigned long flags; 1703 1704 /* Prevent the device and bus from going away while 1705 * the unlink is carried out. If they are already gone 1706 * then urb->use_count must be 0, since disconnected 1707 * devices can't have any active URBs. 1708 */ 1709 spin_lock_irqsave(&hcd_urb_unlink_lock, flags); 1710 if (atomic_read(&urb->use_count) > 0) { 1711 retval = 0; 1712 usb_get_dev(udev); 1713 } 1714 spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags); 1715 if (retval == 0) { 1716 hcd = bus_to_hcd(urb->dev->bus); 1717 retval = unlink1(hcd, urb, status); 1718 if (retval == 0) 1719 retval = -EINPROGRESS; 1720 else if (retval != -EIDRM && retval != -EBUSY) 1721 dev_dbg(&udev->dev, "hcd_unlink_urb %p fail %d\n", 1722 urb, retval); 1723 usb_put_dev(udev); 1724 } 1725 return retval; 1726 } 1727 1728 /*-------------------------------------------------------------------------*/ 1729 1730 static void __usb_hcd_giveback_urb(struct urb *urb) 1731 { 1732 struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); 1733 struct usb_anchor *anchor = urb->anchor; 1734 int status = urb->unlinked; 1735 unsigned long flags; 1736 1737 urb->hcpriv = NULL; 1738 if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) && 1739 urb->actual_length < urb->transfer_buffer_length && 1740 !status)) 1741 status = -EREMOTEIO; 1742 1743 unmap_urb_for_dma(hcd, urb); 1744 usbmon_urb_complete(&hcd->self, urb, status); 1745 usb_anchor_suspend_wakeups(anchor); 1746 usb_unanchor_urb(urb); 1747 if (likely(status == 0)) 1748 usb_led_activity(USB_LED_EVENT_HOST); 1749 1750 /* pass ownership to the completion handler */ 1751 urb->status = status; 1752 1753 /* 1754 * We disable local IRQs here avoid possible deadlock because 1755 * drivers may call spin_lock() to hold lock which might be 1756 * acquired in one hard interrupt handler. 1757 * 1758 * The local_irq_save()/local_irq_restore() around complete() 1759 * will be removed if current USB drivers have been cleaned up 1760 * and no one may trigger the above deadlock situation when 1761 * running complete() in tasklet. 1762 */ 1763 local_irq_save(flags); 1764 urb->complete(urb); 1765 local_irq_restore(flags); 1766 1767 usb_anchor_resume_wakeups(anchor); 1768 atomic_dec(&urb->use_count); 1769 if (unlikely(atomic_read(&urb->reject))) 1770 wake_up(&usb_kill_urb_queue); 1771 usb_put_urb(urb); 1772 } 1773 1774 static void usb_giveback_urb_bh(unsigned long param) 1775 { 1776 struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param; 1777 struct list_head local_list; 1778 1779 spin_lock_irq(&bh->lock); 1780 bh->running = true; 1781 restart: 1782 list_replace_init(&bh->head, &local_list); 1783 spin_unlock_irq(&bh->lock); 1784 1785 while (!list_empty(&local_list)) { 1786 struct urb *urb; 1787 1788 urb = list_entry(local_list.next, struct urb, urb_list); 1789 list_del_init(&urb->urb_list); 1790 bh->completing_ep = urb->ep; 1791 __usb_hcd_giveback_urb(urb); 1792 bh->completing_ep = NULL; 1793 } 1794 1795 /* check if there are new URBs to giveback */ 1796 spin_lock_irq(&bh->lock); 1797 if (!list_empty(&bh->head)) 1798 goto restart; 1799 bh->running = false; 1800 spin_unlock_irq(&bh->lock); 1801 } 1802 1803 /** 1804 * usb_hcd_giveback_urb - return URB from HCD to device driver 1805 * @hcd: host controller returning the URB 1806 * @urb: urb being returned to the USB device driver. 1807 * @status: completion status code for the URB. 1808 * Context: in_interrupt() 1809 * 1810 * This hands the URB from HCD to its USB device driver, using its 1811 * completion function. The HCD has freed all per-urb resources 1812 * (and is done using urb->hcpriv). It also released all HCD locks; 1813 * the device driver won't cause problems if it frees, modifies, 1814 * or resubmits this URB. 1815 * 1816 * If @urb was unlinked, the value of @status will be overridden by 1817 * @urb->unlinked. Erroneous short transfers are detected in case 1818 * the HCD hasn't checked for them. 1819 */ 1820 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status) 1821 { 1822 struct giveback_urb_bh *bh; 1823 bool running, high_prio_bh; 1824 1825 /* pass status to tasklet via unlinked */ 1826 if (likely(!urb->unlinked)) 1827 urb->unlinked = status; 1828 1829 if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) { 1830 __usb_hcd_giveback_urb(urb); 1831 return; 1832 } 1833 1834 if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) { 1835 bh = &hcd->high_prio_bh; 1836 high_prio_bh = true; 1837 } else { 1838 bh = &hcd->low_prio_bh; 1839 high_prio_bh = false; 1840 } 1841 1842 spin_lock(&bh->lock); 1843 list_add_tail(&urb->urb_list, &bh->head); 1844 running = bh->running; 1845 spin_unlock(&bh->lock); 1846 1847 if (running) 1848 ; 1849 else if (high_prio_bh) 1850 tasklet_hi_schedule(&bh->bh); 1851 else 1852 tasklet_schedule(&bh->bh); 1853 } 1854 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb); 1855 1856 /*-------------------------------------------------------------------------*/ 1857 1858 /* Cancel all URBs pending on this endpoint and wait for the endpoint's 1859 * queue to drain completely. The caller must first insure that no more 1860 * URBs can be submitted for this endpoint. 1861 */ 1862 void usb_hcd_flush_endpoint(struct usb_device *udev, 1863 struct usb_host_endpoint *ep) 1864 { 1865 struct usb_hcd *hcd; 1866 struct urb *urb; 1867 1868 if (!ep) 1869 return; 1870 might_sleep(); 1871 hcd = bus_to_hcd(udev->bus); 1872 1873 /* No more submits can occur */ 1874 spin_lock_irq(&hcd_urb_list_lock); 1875 rescan: 1876 list_for_each_entry (urb, &ep->urb_list, urb_list) { 1877 int is_in; 1878 1879 if (urb->unlinked) 1880 continue; 1881 usb_get_urb (urb); 1882 is_in = usb_urb_dir_in(urb); 1883 spin_unlock(&hcd_urb_list_lock); 1884 1885 /* kick hcd */ 1886 unlink1(hcd, urb, -ESHUTDOWN); 1887 dev_dbg (hcd->self.controller, 1888 "shutdown urb %p ep%d%s%s\n", 1889 urb, usb_endpoint_num(&ep->desc), 1890 is_in ? "in" : "out", 1891 ({ char *s; 1892 1893 switch (usb_endpoint_type(&ep->desc)) { 1894 case USB_ENDPOINT_XFER_CONTROL: 1895 s = ""; break; 1896 case USB_ENDPOINT_XFER_BULK: 1897 s = "-bulk"; break; 1898 case USB_ENDPOINT_XFER_INT: 1899 s = "-intr"; break; 1900 default: 1901 s = "-iso"; break; 1902 }; 1903 s; 1904 })); 1905 usb_put_urb (urb); 1906 1907 /* list contents may have changed */ 1908 spin_lock(&hcd_urb_list_lock); 1909 goto rescan; 1910 } 1911 spin_unlock_irq(&hcd_urb_list_lock); 1912 1913 /* Wait until the endpoint queue is completely empty */ 1914 while (!list_empty (&ep->urb_list)) { 1915 spin_lock_irq(&hcd_urb_list_lock); 1916 1917 /* The list may have changed while we acquired the spinlock */ 1918 urb = NULL; 1919 if (!list_empty (&ep->urb_list)) { 1920 urb = list_entry (ep->urb_list.prev, struct urb, 1921 urb_list); 1922 usb_get_urb (urb); 1923 } 1924 spin_unlock_irq(&hcd_urb_list_lock); 1925 1926 if (urb) { 1927 usb_kill_urb (urb); 1928 usb_put_urb (urb); 1929 } 1930 } 1931 } 1932 1933 /** 1934 * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds 1935 * the bus bandwidth 1936 * @udev: target &usb_device 1937 * @new_config: new configuration to install 1938 * @cur_alt: the current alternate interface setting 1939 * @new_alt: alternate interface setting that is being installed 1940 * 1941 * To change configurations, pass in the new configuration in new_config, 1942 * and pass NULL for cur_alt and new_alt. 1943 * 1944 * To reset a device's configuration (put the device in the ADDRESSED state), 1945 * pass in NULL for new_config, cur_alt, and new_alt. 1946 * 1947 * To change alternate interface settings, pass in NULL for new_config, 1948 * pass in the current alternate interface setting in cur_alt, 1949 * and pass in the new alternate interface setting in new_alt. 1950 * 1951 * Return: An error if the requested bandwidth change exceeds the 1952 * bus bandwidth or host controller internal resources. 1953 */ 1954 int usb_hcd_alloc_bandwidth(struct usb_device *udev, 1955 struct usb_host_config *new_config, 1956 struct usb_host_interface *cur_alt, 1957 struct usb_host_interface *new_alt) 1958 { 1959 int num_intfs, i, j; 1960 struct usb_host_interface *alt = NULL; 1961 int ret = 0; 1962 struct usb_hcd *hcd; 1963 struct usb_host_endpoint *ep; 1964 1965 hcd = bus_to_hcd(udev->bus); 1966 if (!hcd->driver->check_bandwidth) 1967 return 0; 1968 1969 /* Configuration is being removed - set configuration 0 */ 1970 if (!new_config && !cur_alt) { 1971 for (i = 1; i < 16; ++i) { 1972 ep = udev->ep_out[i]; 1973 if (ep) 1974 hcd->driver->drop_endpoint(hcd, udev, ep); 1975 ep = udev->ep_in[i]; 1976 if (ep) 1977 hcd->driver->drop_endpoint(hcd, udev, ep); 1978 } 1979 hcd->driver->check_bandwidth(hcd, udev); 1980 return 0; 1981 } 1982 /* Check if the HCD says there's enough bandwidth. Enable all endpoints 1983 * each interface's alt setting 0 and ask the HCD to check the bandwidth 1984 * of the bus. There will always be bandwidth for endpoint 0, so it's 1985 * ok to exclude it. 1986 */ 1987 if (new_config) { 1988 num_intfs = new_config->desc.bNumInterfaces; 1989 /* Remove endpoints (except endpoint 0, which is always on the 1990 * schedule) from the old config from the schedule 1991 */ 1992 for (i = 1; i < 16; ++i) { 1993 ep = udev->ep_out[i]; 1994 if (ep) { 1995 ret = hcd->driver->drop_endpoint(hcd, udev, ep); 1996 if (ret < 0) 1997 goto reset; 1998 } 1999 ep = udev->ep_in[i]; 2000 if (ep) { 2001 ret = hcd->driver->drop_endpoint(hcd, udev, ep); 2002 if (ret < 0) 2003 goto reset; 2004 } 2005 } 2006 for (i = 0; i < num_intfs; ++i) { 2007 struct usb_host_interface *first_alt; 2008 int iface_num; 2009 2010 first_alt = &new_config->intf_cache[i]->altsetting[0]; 2011 iface_num = first_alt->desc.bInterfaceNumber; 2012 /* Set up endpoints for alternate interface setting 0 */ 2013 alt = usb_find_alt_setting(new_config, iface_num, 0); 2014 if (!alt) 2015 /* No alt setting 0? Pick the first setting. */ 2016 alt = first_alt; 2017 2018 for (j = 0; j < alt->desc.bNumEndpoints; j++) { 2019 ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]); 2020 if (ret < 0) 2021 goto reset; 2022 } 2023 } 2024 } 2025 if (cur_alt && new_alt) { 2026 struct usb_interface *iface = usb_ifnum_to_if(udev, 2027 cur_alt->desc.bInterfaceNumber); 2028 2029 if (!iface) 2030 return -EINVAL; 2031 if (iface->resetting_device) { 2032 /* 2033 * The USB core just reset the device, so the xHCI host 2034 * and the device will think alt setting 0 is installed. 2035 * However, the USB core will pass in the alternate 2036 * setting installed before the reset as cur_alt. Dig 2037 * out the alternate setting 0 structure, or the first 2038 * alternate setting if a broken device doesn't have alt 2039 * setting 0. 2040 */ 2041 cur_alt = usb_altnum_to_altsetting(iface, 0); 2042 if (!cur_alt) 2043 cur_alt = &iface->altsetting[0]; 2044 } 2045 2046 /* Drop all the endpoints in the current alt setting */ 2047 for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) { 2048 ret = hcd->driver->drop_endpoint(hcd, udev, 2049 &cur_alt->endpoint[i]); 2050 if (ret < 0) 2051 goto reset; 2052 } 2053 /* Add all the endpoints in the new alt setting */ 2054 for (i = 0; i < new_alt->desc.bNumEndpoints; i++) { 2055 ret = hcd->driver->add_endpoint(hcd, udev, 2056 &new_alt->endpoint[i]); 2057 if (ret < 0) 2058 goto reset; 2059 } 2060 } 2061 ret = hcd->driver->check_bandwidth(hcd, udev); 2062 reset: 2063 if (ret < 0) 2064 hcd->driver->reset_bandwidth(hcd, udev); 2065 return ret; 2066 } 2067 2068 /* Disables the endpoint: synchronizes with the hcd to make sure all 2069 * endpoint state is gone from hardware. usb_hcd_flush_endpoint() must 2070 * have been called previously. Use for set_configuration, set_interface, 2071 * driver removal, physical disconnect. 2072 * 2073 * example: a qh stored in ep->hcpriv, holding state related to endpoint 2074 * type, maxpacket size, toggle, halt status, and scheduling. 2075 */ 2076 void usb_hcd_disable_endpoint(struct usb_device *udev, 2077 struct usb_host_endpoint *ep) 2078 { 2079 struct usb_hcd *hcd; 2080 2081 might_sleep(); 2082 hcd = bus_to_hcd(udev->bus); 2083 if (hcd->driver->endpoint_disable) 2084 hcd->driver->endpoint_disable(hcd, ep); 2085 } 2086 2087 /** 2088 * usb_hcd_reset_endpoint - reset host endpoint state 2089 * @udev: USB device. 2090 * @ep: the endpoint to reset. 2091 * 2092 * Resets any host endpoint state such as the toggle bit, sequence 2093 * number and current window. 2094 */ 2095 void usb_hcd_reset_endpoint(struct usb_device *udev, 2096 struct usb_host_endpoint *ep) 2097 { 2098 struct usb_hcd *hcd = bus_to_hcd(udev->bus); 2099 2100 if (hcd->driver->endpoint_reset) 2101 hcd->driver->endpoint_reset(hcd, ep); 2102 else { 2103 int epnum = usb_endpoint_num(&ep->desc); 2104 int is_out = usb_endpoint_dir_out(&ep->desc); 2105 int is_control = usb_endpoint_xfer_control(&ep->desc); 2106 2107 usb_settoggle(udev, epnum, is_out, 0); 2108 if (is_control) 2109 usb_settoggle(udev, epnum, !is_out, 0); 2110 } 2111 } 2112 2113 /** 2114 * usb_alloc_streams - allocate bulk endpoint stream IDs. 2115 * @interface: alternate setting that includes all endpoints. 2116 * @eps: array of endpoints that need streams. 2117 * @num_eps: number of endpoints in the array. 2118 * @num_streams: number of streams to allocate. 2119 * @mem_flags: flags hcd should use to allocate memory. 2120 * 2121 * Sets up a group of bulk endpoints to have @num_streams stream IDs available. 2122 * Drivers may queue multiple transfers to different stream IDs, which may 2123 * complete in a different order than they were queued. 2124 * 2125 * Return: On success, the number of allocated streams. On failure, a negative 2126 * error code. 2127 */ 2128 int usb_alloc_streams(struct usb_interface *interface, 2129 struct usb_host_endpoint **eps, unsigned int num_eps, 2130 unsigned int num_streams, gfp_t mem_flags) 2131 { 2132 struct usb_hcd *hcd; 2133 struct usb_device *dev; 2134 int i, ret; 2135 2136 dev = interface_to_usbdev(interface); 2137 hcd = bus_to_hcd(dev->bus); 2138 if (!hcd->driver->alloc_streams || !hcd->driver->free_streams) 2139 return -EINVAL; 2140 if (dev->speed < USB_SPEED_SUPER) 2141 return -EINVAL; 2142 if (dev->state < USB_STATE_CONFIGURED) 2143 return -ENODEV; 2144 2145 for (i = 0; i < num_eps; i++) { 2146 /* Streams only apply to bulk endpoints. */ 2147 if (!usb_endpoint_xfer_bulk(&eps[i]->desc)) 2148 return -EINVAL; 2149 /* Re-alloc is not allowed */ 2150 if (eps[i]->streams) 2151 return -EINVAL; 2152 } 2153 2154 ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps, 2155 num_streams, mem_flags); 2156 if (ret < 0) 2157 return ret; 2158 2159 for (i = 0; i < num_eps; i++) 2160 eps[i]->streams = ret; 2161 2162 return ret; 2163 } 2164 EXPORT_SYMBOL_GPL(usb_alloc_streams); 2165 2166 /** 2167 * usb_free_streams - free bulk endpoint stream IDs. 2168 * @interface: alternate setting that includes all endpoints. 2169 * @eps: array of endpoints to remove streams from. 2170 * @num_eps: number of endpoints in the array. 2171 * @mem_flags: flags hcd should use to allocate memory. 2172 * 2173 * Reverts a group of bulk endpoints back to not using stream IDs. 2174 * Can fail if we are given bad arguments, or HCD is broken. 2175 * 2176 * Return: 0 on success. On failure, a negative error code. 2177 */ 2178 int usb_free_streams(struct usb_interface *interface, 2179 struct usb_host_endpoint **eps, unsigned int num_eps, 2180 gfp_t mem_flags) 2181 { 2182 struct usb_hcd *hcd; 2183 struct usb_device *dev; 2184 int i, ret; 2185 2186 dev = interface_to_usbdev(interface); 2187 hcd = bus_to_hcd(dev->bus); 2188 if (dev->speed < USB_SPEED_SUPER) 2189 return -EINVAL; 2190 2191 /* Double-free is not allowed */ 2192 for (i = 0; i < num_eps; i++) 2193 if (!eps[i] || !eps[i]->streams) 2194 return -EINVAL; 2195 2196 ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags); 2197 if (ret < 0) 2198 return ret; 2199 2200 for (i = 0; i < num_eps; i++) 2201 eps[i]->streams = 0; 2202 2203 return ret; 2204 } 2205 EXPORT_SYMBOL_GPL(usb_free_streams); 2206 2207 /* Protect against drivers that try to unlink URBs after the device 2208 * is gone, by waiting until all unlinks for @udev are finished. 2209 * Since we don't currently track URBs by device, simply wait until 2210 * nothing is running in the locked region of usb_hcd_unlink_urb(). 2211 */ 2212 void usb_hcd_synchronize_unlinks(struct usb_device *udev) 2213 { 2214 spin_lock_irq(&hcd_urb_unlink_lock); 2215 spin_unlock_irq(&hcd_urb_unlink_lock); 2216 } 2217 2218 /*-------------------------------------------------------------------------*/ 2219 2220 /* called in any context */ 2221 int usb_hcd_get_frame_number (struct usb_device *udev) 2222 { 2223 struct usb_hcd *hcd = bus_to_hcd(udev->bus); 2224 2225 if (!HCD_RH_RUNNING(hcd)) 2226 return -ESHUTDOWN; 2227 return hcd->driver->get_frame_number (hcd); 2228 } 2229 2230 /*-------------------------------------------------------------------------*/ 2231 2232 #ifdef CONFIG_PM 2233 2234 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg) 2235 { 2236 struct usb_hcd *hcd = bus_to_hcd(rhdev->bus); 2237 int status; 2238 int old_state = hcd->state; 2239 2240 dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n", 2241 (PMSG_IS_AUTO(msg) ? "auto-" : ""), 2242 rhdev->do_remote_wakeup); 2243 if (HCD_DEAD(hcd)) { 2244 dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend"); 2245 return 0; 2246 } 2247 2248 if (!hcd->driver->bus_suspend) { 2249 status = -ENOENT; 2250 } else { 2251 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2252 hcd->state = HC_STATE_QUIESCING; 2253 status = hcd->driver->bus_suspend(hcd); 2254 } 2255 if (status == 0) { 2256 usb_set_device_state(rhdev, USB_STATE_SUSPENDED); 2257 hcd->state = HC_STATE_SUSPENDED; 2258 2259 /* Did we race with a root-hub wakeup event? */ 2260 if (rhdev->do_remote_wakeup) { 2261 char buffer[6]; 2262 2263 status = hcd->driver->hub_status_data(hcd, buffer); 2264 if (status != 0) { 2265 dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n"); 2266 hcd_bus_resume(rhdev, PMSG_AUTO_RESUME); 2267 status = -EBUSY; 2268 } 2269 } 2270 } else { 2271 spin_lock_irq(&hcd_root_hub_lock); 2272 if (!HCD_DEAD(hcd)) { 2273 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2274 hcd->state = old_state; 2275 } 2276 spin_unlock_irq(&hcd_root_hub_lock); 2277 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", 2278 "suspend", status); 2279 } 2280 return status; 2281 } 2282 2283 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) 2284 { 2285 struct usb_hcd *hcd = bus_to_hcd(rhdev->bus); 2286 int status; 2287 int old_state = hcd->state; 2288 2289 dev_dbg(&rhdev->dev, "usb %sresume\n", 2290 (PMSG_IS_AUTO(msg) ? "auto-" : "")); 2291 if (HCD_DEAD(hcd)) { 2292 dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume"); 2293 return 0; 2294 } 2295 if (!hcd->driver->bus_resume) 2296 return -ENOENT; 2297 if (HCD_RH_RUNNING(hcd)) 2298 return 0; 2299 2300 hcd->state = HC_STATE_RESUMING; 2301 status = hcd->driver->bus_resume(hcd); 2302 clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); 2303 if (status == 0) { 2304 struct usb_device *udev; 2305 int port1; 2306 2307 spin_lock_irq(&hcd_root_hub_lock); 2308 if (!HCD_DEAD(hcd)) { 2309 usb_set_device_state(rhdev, rhdev->actconfig 2310 ? USB_STATE_CONFIGURED 2311 : USB_STATE_ADDRESS); 2312 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2313 hcd->state = HC_STATE_RUNNING; 2314 } 2315 spin_unlock_irq(&hcd_root_hub_lock); 2316 2317 /* 2318 * Check whether any of the enabled ports on the root hub are 2319 * unsuspended. If they are then a TRSMRCY delay is needed 2320 * (this is what the USB-2 spec calls a "global resume"). 2321 * Otherwise we can skip the delay. 2322 */ 2323 usb_hub_for_each_child(rhdev, port1, udev) { 2324 if (udev->state != USB_STATE_NOTATTACHED && 2325 !udev->port_is_suspended) { 2326 usleep_range(10000, 11000); /* TRSMRCY */ 2327 break; 2328 } 2329 } 2330 } else { 2331 hcd->state = old_state; 2332 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", 2333 "resume", status); 2334 if (status != -ESHUTDOWN) 2335 usb_hc_died(hcd); 2336 } 2337 return status; 2338 } 2339 2340 /* Workqueue routine for root-hub remote wakeup */ 2341 static void hcd_resume_work(struct work_struct *work) 2342 { 2343 struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work); 2344 struct usb_device *udev = hcd->self.root_hub; 2345 2346 usb_remote_wakeup(udev); 2347 } 2348 2349 /** 2350 * usb_hcd_resume_root_hub - called by HCD to resume its root hub 2351 * @hcd: host controller for this root hub 2352 * 2353 * The USB host controller calls this function when its root hub is 2354 * suspended (with the remote wakeup feature enabled) and a remote 2355 * wakeup request is received. The routine submits a workqueue request 2356 * to resume the root hub (that is, manage its downstream ports again). 2357 */ 2358 void usb_hcd_resume_root_hub (struct usb_hcd *hcd) 2359 { 2360 unsigned long flags; 2361 2362 spin_lock_irqsave (&hcd_root_hub_lock, flags); 2363 if (hcd->rh_registered) { 2364 set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); 2365 queue_work(pm_wq, &hcd->wakeup_work); 2366 } 2367 spin_unlock_irqrestore (&hcd_root_hub_lock, flags); 2368 } 2369 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub); 2370 2371 #endif /* CONFIG_PM */ 2372 2373 /*-------------------------------------------------------------------------*/ 2374 2375 #ifdef CONFIG_USB_OTG 2376 2377 /** 2378 * usb_bus_start_enum - start immediate enumeration (for OTG) 2379 * @bus: the bus (must use hcd framework) 2380 * @port_num: 1-based number of port; usually bus->otg_port 2381 * Context: in_interrupt() 2382 * 2383 * Starts enumeration, with an immediate reset followed later by 2384 * hub_wq identifying and possibly configuring the device. 2385 * This is needed by OTG controller drivers, where it helps meet 2386 * HNP protocol timing requirements for starting a port reset. 2387 * 2388 * Return: 0 if successful. 2389 */ 2390 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num) 2391 { 2392 struct usb_hcd *hcd; 2393 int status = -EOPNOTSUPP; 2394 2395 /* NOTE: since HNP can't start by grabbing the bus's address0_sem, 2396 * boards with root hubs hooked up to internal devices (instead of 2397 * just the OTG port) may need more attention to resetting... 2398 */ 2399 hcd = bus_to_hcd(bus); 2400 if (port_num && hcd->driver->start_port_reset) 2401 status = hcd->driver->start_port_reset(hcd, port_num); 2402 2403 /* allocate hub_wq shortly after (first) root port reset finishes; 2404 * it may issue others, until at least 50 msecs have passed. 2405 */ 2406 if (status == 0) 2407 mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10)); 2408 return status; 2409 } 2410 EXPORT_SYMBOL_GPL(usb_bus_start_enum); 2411 2412 #endif 2413 2414 /*-------------------------------------------------------------------------*/ 2415 2416 /** 2417 * usb_hcd_irq - hook IRQs to HCD framework (bus glue) 2418 * @irq: the IRQ being raised 2419 * @__hcd: pointer to the HCD whose IRQ is being signaled 2420 * 2421 * If the controller isn't HALTed, calls the driver's irq handler. 2422 * Checks whether the controller is now dead. 2423 * 2424 * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise. 2425 */ 2426 irqreturn_t usb_hcd_irq (int irq, void *__hcd) 2427 { 2428 struct usb_hcd *hcd = __hcd; 2429 irqreturn_t rc; 2430 2431 if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd))) 2432 rc = IRQ_NONE; 2433 else if (hcd->driver->irq(hcd) == IRQ_NONE) 2434 rc = IRQ_NONE; 2435 else 2436 rc = IRQ_HANDLED; 2437 2438 return rc; 2439 } 2440 EXPORT_SYMBOL_GPL(usb_hcd_irq); 2441 2442 /*-------------------------------------------------------------------------*/ 2443 2444 /** 2445 * usb_hc_died - report abnormal shutdown of a host controller (bus glue) 2446 * @hcd: pointer to the HCD representing the controller 2447 * 2448 * This is called by bus glue to report a USB host controller that died 2449 * while operations may still have been pending. It's called automatically 2450 * by the PCI glue, so only glue for non-PCI busses should need to call it. 2451 * 2452 * Only call this function with the primary HCD. 2453 */ 2454 void usb_hc_died (struct usb_hcd *hcd) 2455 { 2456 unsigned long flags; 2457 2458 dev_err (hcd->self.controller, "HC died; cleaning up\n"); 2459 2460 spin_lock_irqsave (&hcd_root_hub_lock, flags); 2461 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2462 set_bit(HCD_FLAG_DEAD, &hcd->flags); 2463 if (hcd->rh_registered) { 2464 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2465 2466 /* make hub_wq clean up old urbs and devices */ 2467 usb_set_device_state (hcd->self.root_hub, 2468 USB_STATE_NOTATTACHED); 2469 usb_kick_hub_wq(hcd->self.root_hub); 2470 } 2471 if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) { 2472 hcd = hcd->shared_hcd; 2473 if (hcd->rh_registered) { 2474 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2475 2476 /* make hub_wq clean up old urbs and devices */ 2477 usb_set_device_state(hcd->self.root_hub, 2478 USB_STATE_NOTATTACHED); 2479 usb_kick_hub_wq(hcd->self.root_hub); 2480 } 2481 } 2482 spin_unlock_irqrestore (&hcd_root_hub_lock, flags); 2483 /* Make sure that the other roothub is also deallocated. */ 2484 } 2485 EXPORT_SYMBOL_GPL (usb_hc_died); 2486 2487 /*-------------------------------------------------------------------------*/ 2488 2489 static void init_giveback_urb_bh(struct giveback_urb_bh *bh) 2490 { 2491 2492 spin_lock_init(&bh->lock); 2493 INIT_LIST_HEAD(&bh->head); 2494 tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh); 2495 } 2496 2497 /** 2498 * usb_create_shared_hcd - create and initialize an HCD structure 2499 * @driver: HC driver that will use this hcd 2500 * @dev: device for this HC, stored in hcd->self.controller 2501 * @bus_name: value to store in hcd->self.bus_name 2502 * @primary_hcd: a pointer to the usb_hcd structure that is sharing the 2503 * PCI device. Only allocate certain resources for the primary HCD 2504 * Context: !in_interrupt() 2505 * 2506 * Allocate a struct usb_hcd, with extra space at the end for the 2507 * HC driver's private data. Initialize the generic members of the 2508 * hcd structure. 2509 * 2510 * Return: On success, a pointer to the created and initialized HCD structure. 2511 * On failure (e.g. if memory is unavailable), %NULL. 2512 */ 2513 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver, 2514 struct device *dev, const char *bus_name, 2515 struct usb_hcd *primary_hcd) 2516 { 2517 struct usb_hcd *hcd; 2518 2519 hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL); 2520 if (!hcd) { 2521 dev_dbg (dev, "hcd alloc failed\n"); 2522 return NULL; 2523 } 2524 if (primary_hcd == NULL) { 2525 hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex), 2526 GFP_KERNEL); 2527 if (!hcd->address0_mutex) { 2528 kfree(hcd); 2529 dev_dbg(dev, "hcd address0 mutex alloc failed\n"); 2530 return NULL; 2531 } 2532 mutex_init(hcd->address0_mutex); 2533 hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex), 2534 GFP_KERNEL); 2535 if (!hcd->bandwidth_mutex) { 2536 kfree(hcd); 2537 dev_dbg(dev, "hcd bandwidth mutex alloc failed\n"); 2538 return NULL; 2539 } 2540 mutex_init(hcd->bandwidth_mutex); 2541 dev_set_drvdata(dev, hcd); 2542 } else { 2543 mutex_lock(&usb_port_peer_mutex); 2544 hcd->address0_mutex = primary_hcd->address0_mutex; 2545 hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex; 2546 hcd->primary_hcd = primary_hcd; 2547 primary_hcd->primary_hcd = primary_hcd; 2548 hcd->shared_hcd = primary_hcd; 2549 primary_hcd->shared_hcd = hcd; 2550 mutex_unlock(&usb_port_peer_mutex); 2551 } 2552 2553 kref_init(&hcd->kref); 2554 2555 usb_bus_init(&hcd->self); 2556 hcd->self.controller = dev; 2557 hcd->self.bus_name = bus_name; 2558 hcd->self.uses_dma = (dev->dma_mask != NULL); 2559 2560 init_timer(&hcd->rh_timer); 2561 hcd->rh_timer.function = rh_timer_func; 2562 hcd->rh_timer.data = (unsigned long) hcd; 2563 #ifdef CONFIG_PM 2564 INIT_WORK(&hcd->wakeup_work, hcd_resume_work); 2565 #endif 2566 2567 hcd->driver = driver; 2568 hcd->speed = driver->flags & HCD_MASK; 2569 hcd->product_desc = (driver->product_desc) ? driver->product_desc : 2570 "USB Host Controller"; 2571 return hcd; 2572 } 2573 EXPORT_SYMBOL_GPL(usb_create_shared_hcd); 2574 2575 /** 2576 * usb_create_hcd - create and initialize an HCD structure 2577 * @driver: HC driver that will use this hcd 2578 * @dev: device for this HC, stored in hcd->self.controller 2579 * @bus_name: value to store in hcd->self.bus_name 2580 * Context: !in_interrupt() 2581 * 2582 * Allocate a struct usb_hcd, with extra space at the end for the 2583 * HC driver's private data. Initialize the generic members of the 2584 * hcd structure. 2585 * 2586 * Return: On success, a pointer to the created and initialized HCD 2587 * structure. On failure (e.g. if memory is unavailable), %NULL. 2588 */ 2589 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver, 2590 struct device *dev, const char *bus_name) 2591 { 2592 return usb_create_shared_hcd(driver, dev, bus_name, NULL); 2593 } 2594 EXPORT_SYMBOL_GPL(usb_create_hcd); 2595 2596 /* 2597 * Roothubs that share one PCI device must also share the bandwidth mutex. 2598 * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is 2599 * deallocated. 2600 * 2601 * Make sure to deallocate the bandwidth_mutex only when the last HCD is 2602 * freed. When hcd_release() is called for either hcd in a peer set, 2603 * invalidate the peer's ->shared_hcd and ->primary_hcd pointers. 2604 */ 2605 static void hcd_release(struct kref *kref) 2606 { 2607 struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref); 2608 2609 mutex_lock(&usb_port_peer_mutex); 2610 if (hcd->shared_hcd) { 2611 struct usb_hcd *peer = hcd->shared_hcd; 2612 2613 peer->shared_hcd = NULL; 2614 peer->primary_hcd = NULL; 2615 } else { 2616 kfree(hcd->address0_mutex); 2617 kfree(hcd->bandwidth_mutex); 2618 } 2619 mutex_unlock(&usb_port_peer_mutex); 2620 kfree(hcd); 2621 } 2622 2623 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd) 2624 { 2625 if (hcd) 2626 kref_get (&hcd->kref); 2627 return hcd; 2628 } 2629 EXPORT_SYMBOL_GPL(usb_get_hcd); 2630 2631 void usb_put_hcd (struct usb_hcd *hcd) 2632 { 2633 if (hcd) 2634 kref_put (&hcd->kref, hcd_release); 2635 } 2636 EXPORT_SYMBOL_GPL(usb_put_hcd); 2637 2638 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd) 2639 { 2640 if (!hcd->primary_hcd) 2641 return 1; 2642 return hcd == hcd->primary_hcd; 2643 } 2644 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd); 2645 2646 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1) 2647 { 2648 if (!hcd->driver->find_raw_port_number) 2649 return port1; 2650 2651 return hcd->driver->find_raw_port_number(hcd, port1); 2652 } 2653 2654 static int usb_hcd_request_irqs(struct usb_hcd *hcd, 2655 unsigned int irqnum, unsigned long irqflags) 2656 { 2657 int retval; 2658 2659 if (hcd->driver->irq) { 2660 2661 snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d", 2662 hcd->driver->description, hcd->self.busnum); 2663 retval = request_irq(irqnum, &usb_hcd_irq, irqflags, 2664 hcd->irq_descr, hcd); 2665 if (retval != 0) { 2666 dev_err(hcd->self.controller, 2667 "request interrupt %d failed\n", 2668 irqnum); 2669 return retval; 2670 } 2671 hcd->irq = irqnum; 2672 dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum, 2673 (hcd->driver->flags & HCD_MEMORY) ? 2674 "io mem" : "io base", 2675 (unsigned long long)hcd->rsrc_start); 2676 } else { 2677 hcd->irq = 0; 2678 if (hcd->rsrc_start) 2679 dev_info(hcd->self.controller, "%s 0x%08llx\n", 2680 (hcd->driver->flags & HCD_MEMORY) ? 2681 "io mem" : "io base", 2682 (unsigned long long)hcd->rsrc_start); 2683 } 2684 return 0; 2685 } 2686 2687 /* 2688 * Before we free this root hub, flush in-flight peering attempts 2689 * and disable peer lookups 2690 */ 2691 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd) 2692 { 2693 struct usb_device *rhdev; 2694 2695 mutex_lock(&usb_port_peer_mutex); 2696 rhdev = hcd->self.root_hub; 2697 hcd->self.root_hub = NULL; 2698 mutex_unlock(&usb_port_peer_mutex); 2699 usb_put_dev(rhdev); 2700 } 2701 2702 /** 2703 * usb_add_hcd - finish generic HCD structure initialization and register 2704 * @hcd: the usb_hcd structure to initialize 2705 * @irqnum: Interrupt line to allocate 2706 * @irqflags: Interrupt type flags 2707 * 2708 * Finish the remaining parts of generic HCD initialization: allocate the 2709 * buffers of consistent memory, register the bus, request the IRQ line, 2710 * and call the driver's reset() and start() routines. 2711 */ 2712 int usb_add_hcd(struct usb_hcd *hcd, 2713 unsigned int irqnum, unsigned long irqflags) 2714 { 2715 int retval; 2716 struct usb_device *rhdev; 2717 2718 if (IS_ENABLED(CONFIG_USB_PHY) && !hcd->usb_phy) { 2719 struct usb_phy *phy = usb_get_phy_dev(hcd->self.controller, 0); 2720 2721 if (IS_ERR(phy)) { 2722 retval = PTR_ERR(phy); 2723 if (retval == -EPROBE_DEFER) 2724 return retval; 2725 } else { 2726 retval = usb_phy_init(phy); 2727 if (retval) { 2728 usb_put_phy(phy); 2729 return retval; 2730 } 2731 hcd->usb_phy = phy; 2732 hcd->remove_phy = 1; 2733 } 2734 } 2735 2736 if (IS_ENABLED(CONFIG_GENERIC_PHY) && !hcd->phy) { 2737 struct phy *phy = phy_get(hcd->self.controller, "usb"); 2738 2739 if (IS_ERR(phy)) { 2740 retval = PTR_ERR(phy); 2741 if (retval == -EPROBE_DEFER) 2742 goto err_phy; 2743 } else { 2744 retval = phy_init(phy); 2745 if (retval) { 2746 phy_put(phy); 2747 goto err_phy; 2748 } 2749 retval = phy_power_on(phy); 2750 if (retval) { 2751 phy_exit(phy); 2752 phy_put(phy); 2753 goto err_phy; 2754 } 2755 hcd->phy = phy; 2756 hcd->remove_phy = 1; 2757 } 2758 } 2759 2760 dev_info(hcd->self.controller, "%s\n", hcd->product_desc); 2761 2762 /* Keep old behaviour if authorized_default is not in [0, 1]. */ 2763 if (authorized_default < 0 || authorized_default > 1) { 2764 if (hcd->wireless) 2765 clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 2766 else 2767 set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 2768 } else { 2769 if (authorized_default) 2770 set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 2771 else 2772 clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 2773 } 2774 set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); 2775 2776 /* per default all interfaces are authorized */ 2777 set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); 2778 2779 /* HC is in reset state, but accessible. Now do the one-time init, 2780 * bottom up so that hcds can customize the root hubs before hub_wq 2781 * starts talking to them. (Note, bus id is assigned early too.) 2782 */ 2783 retval = hcd_buffer_create(hcd); 2784 if (retval != 0) { 2785 dev_dbg(hcd->self.controller, "pool alloc failed\n"); 2786 goto err_create_buf; 2787 } 2788 2789 retval = usb_register_bus(&hcd->self); 2790 if (retval < 0) 2791 goto err_register_bus; 2792 2793 rhdev = usb_alloc_dev(NULL, &hcd->self, 0); 2794 if (rhdev == NULL) { 2795 dev_err(hcd->self.controller, "unable to allocate root hub\n"); 2796 retval = -ENOMEM; 2797 goto err_allocate_root_hub; 2798 } 2799 mutex_lock(&usb_port_peer_mutex); 2800 hcd->self.root_hub = rhdev; 2801 mutex_unlock(&usb_port_peer_mutex); 2802 2803 switch (hcd->speed) { 2804 case HCD_USB11: 2805 rhdev->speed = USB_SPEED_FULL; 2806 break; 2807 case HCD_USB2: 2808 rhdev->speed = USB_SPEED_HIGH; 2809 break; 2810 case HCD_USB25: 2811 rhdev->speed = USB_SPEED_WIRELESS; 2812 break; 2813 case HCD_USB3: 2814 rhdev->speed = USB_SPEED_SUPER; 2815 break; 2816 case HCD_USB31: 2817 rhdev->speed = USB_SPEED_SUPER_PLUS; 2818 break; 2819 default: 2820 retval = -EINVAL; 2821 goto err_set_rh_speed; 2822 } 2823 2824 /* wakeup flag init defaults to "everything works" for root hubs, 2825 * but drivers can override it in reset() if needed, along with 2826 * recording the overall controller's system wakeup capability. 2827 */ 2828 device_set_wakeup_capable(&rhdev->dev, 1); 2829 2830 /* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is 2831 * registered. But since the controller can die at any time, 2832 * let's initialize the flag before touching the hardware. 2833 */ 2834 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2835 2836 /* "reset" is misnamed; its role is now one-time init. the controller 2837 * should already have been reset (and boot firmware kicked off etc). 2838 */ 2839 if (hcd->driver->reset) { 2840 retval = hcd->driver->reset(hcd); 2841 if (retval < 0) { 2842 dev_err(hcd->self.controller, "can't setup: %d\n", 2843 retval); 2844 goto err_hcd_driver_setup; 2845 } 2846 } 2847 hcd->rh_pollable = 1; 2848 2849 /* NOTE: root hub and controller capabilities may not be the same */ 2850 if (device_can_wakeup(hcd->self.controller) 2851 && device_can_wakeup(&hcd->self.root_hub->dev)) 2852 dev_dbg(hcd->self.controller, "supports USB remote wakeup\n"); 2853 2854 /* initialize tasklets */ 2855 init_giveback_urb_bh(&hcd->high_prio_bh); 2856 init_giveback_urb_bh(&hcd->low_prio_bh); 2857 2858 /* enable irqs just before we start the controller, 2859 * if the BIOS provides legacy PCI irqs. 2860 */ 2861 if (usb_hcd_is_primary_hcd(hcd) && irqnum) { 2862 retval = usb_hcd_request_irqs(hcd, irqnum, irqflags); 2863 if (retval) 2864 goto err_request_irq; 2865 } 2866 2867 hcd->state = HC_STATE_RUNNING; 2868 retval = hcd->driver->start(hcd); 2869 if (retval < 0) { 2870 dev_err(hcd->self.controller, "startup error %d\n", retval); 2871 goto err_hcd_driver_start; 2872 } 2873 2874 /* starting here, usbcore will pay attention to this root hub */ 2875 retval = register_root_hub(hcd); 2876 if (retval != 0) 2877 goto err_register_root_hub; 2878 2879 retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group); 2880 if (retval < 0) { 2881 printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n", 2882 retval); 2883 goto error_create_attr_group; 2884 } 2885 if (hcd->uses_new_polling && HCD_POLL_RH(hcd)) 2886 usb_hcd_poll_rh_status(hcd); 2887 2888 return retval; 2889 2890 error_create_attr_group: 2891 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2892 if (HC_IS_RUNNING(hcd->state)) 2893 hcd->state = HC_STATE_QUIESCING; 2894 spin_lock_irq(&hcd_root_hub_lock); 2895 hcd->rh_registered = 0; 2896 spin_unlock_irq(&hcd_root_hub_lock); 2897 2898 #ifdef CONFIG_PM 2899 cancel_work_sync(&hcd->wakeup_work); 2900 #endif 2901 mutex_lock(&usb_bus_idr_lock); 2902 usb_disconnect(&rhdev); /* Sets rhdev to NULL */ 2903 mutex_unlock(&usb_bus_idr_lock); 2904 err_register_root_hub: 2905 hcd->rh_pollable = 0; 2906 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2907 del_timer_sync(&hcd->rh_timer); 2908 hcd->driver->stop(hcd); 2909 hcd->state = HC_STATE_HALT; 2910 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2911 del_timer_sync(&hcd->rh_timer); 2912 err_hcd_driver_start: 2913 if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0) 2914 free_irq(irqnum, hcd); 2915 err_request_irq: 2916 err_hcd_driver_setup: 2917 err_set_rh_speed: 2918 usb_put_invalidate_rhdev(hcd); 2919 err_allocate_root_hub: 2920 usb_deregister_bus(&hcd->self); 2921 err_register_bus: 2922 hcd_buffer_destroy(hcd); 2923 err_create_buf: 2924 if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) { 2925 phy_power_off(hcd->phy); 2926 phy_exit(hcd->phy); 2927 phy_put(hcd->phy); 2928 hcd->phy = NULL; 2929 } 2930 err_phy: 2931 if (hcd->remove_phy && hcd->usb_phy) { 2932 usb_phy_shutdown(hcd->usb_phy); 2933 usb_put_phy(hcd->usb_phy); 2934 hcd->usb_phy = NULL; 2935 } 2936 return retval; 2937 } 2938 EXPORT_SYMBOL_GPL(usb_add_hcd); 2939 2940 /** 2941 * usb_remove_hcd - shutdown processing for generic HCDs 2942 * @hcd: the usb_hcd structure to remove 2943 * Context: !in_interrupt() 2944 * 2945 * Disconnects the root hub, then reverses the effects of usb_add_hcd(), 2946 * invoking the HCD's stop() method. 2947 */ 2948 void usb_remove_hcd(struct usb_hcd *hcd) 2949 { 2950 struct usb_device *rhdev = hcd->self.root_hub; 2951 2952 dev_info(hcd->self.controller, "remove, state %x\n", hcd->state); 2953 2954 usb_get_dev(rhdev); 2955 sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group); 2956 2957 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2958 if (HC_IS_RUNNING (hcd->state)) 2959 hcd->state = HC_STATE_QUIESCING; 2960 2961 dev_dbg(hcd->self.controller, "roothub graceful disconnect\n"); 2962 spin_lock_irq (&hcd_root_hub_lock); 2963 hcd->rh_registered = 0; 2964 spin_unlock_irq (&hcd_root_hub_lock); 2965 2966 #ifdef CONFIG_PM 2967 cancel_work_sync(&hcd->wakeup_work); 2968 #endif 2969 2970 mutex_lock(&usb_bus_idr_lock); 2971 usb_disconnect(&rhdev); /* Sets rhdev to NULL */ 2972 mutex_unlock(&usb_bus_idr_lock); 2973 2974 /* 2975 * tasklet_kill() isn't needed here because: 2976 * - driver's disconnect() called from usb_disconnect() should 2977 * make sure its URBs are completed during the disconnect() 2978 * callback 2979 * 2980 * - it is too late to run complete() here since driver may have 2981 * been removed already now 2982 */ 2983 2984 /* Prevent any more root-hub status calls from the timer. 2985 * The HCD might still restart the timer (if a port status change 2986 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke 2987 * the hub_status_data() callback. 2988 */ 2989 hcd->rh_pollable = 0; 2990 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2991 del_timer_sync(&hcd->rh_timer); 2992 2993 hcd->driver->stop(hcd); 2994 hcd->state = HC_STATE_HALT; 2995 2996 /* In case the HCD restarted the timer, stop it again. */ 2997 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2998 del_timer_sync(&hcd->rh_timer); 2999 3000 if (usb_hcd_is_primary_hcd(hcd)) { 3001 if (hcd->irq > 0) 3002 free_irq(hcd->irq, hcd); 3003 } 3004 3005 usb_deregister_bus(&hcd->self); 3006 hcd_buffer_destroy(hcd); 3007 3008 if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) { 3009 phy_power_off(hcd->phy); 3010 phy_exit(hcd->phy); 3011 phy_put(hcd->phy); 3012 hcd->phy = NULL; 3013 } 3014 if (hcd->remove_phy && hcd->usb_phy) { 3015 usb_phy_shutdown(hcd->usb_phy); 3016 usb_put_phy(hcd->usb_phy); 3017 hcd->usb_phy = NULL; 3018 } 3019 3020 usb_put_invalidate_rhdev(hcd); 3021 } 3022 EXPORT_SYMBOL_GPL(usb_remove_hcd); 3023 3024 void 3025 usb_hcd_platform_shutdown(struct platform_device *dev) 3026 { 3027 struct usb_hcd *hcd = platform_get_drvdata(dev); 3028 3029 if (hcd->driver->shutdown) 3030 hcd->driver->shutdown(hcd); 3031 } 3032 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown); 3033 3034 /*-------------------------------------------------------------------------*/ 3035 3036 #if defined(CONFIG_USB_MON) || defined(CONFIG_USB_MON_MODULE) 3037 3038 const struct usb_mon_operations *mon_ops; 3039 3040 /* 3041 * The registration is unlocked. 3042 * We do it this way because we do not want to lock in hot paths. 3043 * 3044 * Notice that the code is minimally error-proof. Because usbmon needs 3045 * symbols from usbcore, usbcore gets referenced and cannot be unloaded first. 3046 */ 3047 3048 int usb_mon_register(const struct usb_mon_operations *ops) 3049 { 3050 3051 if (mon_ops) 3052 return -EBUSY; 3053 3054 mon_ops = ops; 3055 mb(); 3056 return 0; 3057 } 3058 EXPORT_SYMBOL_GPL (usb_mon_register); 3059 3060 void usb_mon_deregister (void) 3061 { 3062 3063 if (mon_ops == NULL) { 3064 printk(KERN_ERR "USB: monitor was not registered\n"); 3065 return; 3066 } 3067 mon_ops = NULL; 3068 mb(); 3069 } 3070 EXPORT_SYMBOL_GPL (usb_mon_deregister); 3071 3072 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */ 3073