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 #include <linux/usb/otg.h> 50 51 #include "usb.h" 52 53 54 /*-------------------------------------------------------------------------*/ 55 56 /* 57 * USB Host Controller Driver framework 58 * 59 * Plugs into usbcore (usb_bus) and lets HCDs share code, minimizing 60 * HCD-specific behaviors/bugs. 61 * 62 * This does error checks, tracks devices and urbs, and delegates to a 63 * "hc_driver" only for code (and data) that really needs to know about 64 * hardware differences. That includes root hub registers, i/o queues, 65 * and so on ... but as little else as possible. 66 * 67 * Shared code includes most of the "root hub" code (these are emulated, 68 * though each HC's hardware works differently) and PCI glue, plus request 69 * tracking overhead. The HCD code should only block on spinlocks or on 70 * hardware handshaking; blocking on software events (such as other kernel 71 * threads releasing resources, or completing actions) is all generic. 72 * 73 * Happens the USB 2.0 spec says this would be invisible inside the "USBD", 74 * and includes mostly a "HCDI" (HCD Interface) along with some APIs used 75 * only by the hub driver ... and that neither should be seen or used by 76 * usb client device drivers. 77 * 78 * Contributors of ideas or unattributed patches include: David Brownell, 79 * Roman Weissgaerber, Rory Bolt, Greg Kroah-Hartman, ... 80 * 81 * HISTORY: 82 * 2002-02-21 Pull in most of the usb_bus support from usb.c; some 83 * associated cleanup. "usb_hcd" still != "usb_bus". 84 * 2001-12-12 Initial patch version for Linux 2.5.1 kernel. 85 */ 86 87 /*-------------------------------------------------------------------------*/ 88 89 /* Keep track of which host controller drivers are loaded */ 90 unsigned long usb_hcds_loaded; 91 EXPORT_SYMBOL_GPL(usb_hcds_loaded); 92 93 /* host controllers we manage */ 94 DEFINE_IDR (usb_bus_idr); 95 EXPORT_SYMBOL_GPL (usb_bus_idr); 96 97 /* used when allocating bus numbers */ 98 #define USB_MAXBUS 64 99 100 /* used when updating list of hcds */ 101 DEFINE_MUTEX(usb_bus_idr_lock); /* exported only for usbfs */ 102 EXPORT_SYMBOL_GPL (usb_bus_idr_lock); 103 104 /* used for controlling access to virtual root hubs */ 105 static DEFINE_SPINLOCK(hcd_root_hub_lock); 106 107 /* used when updating an endpoint's URB list */ 108 static DEFINE_SPINLOCK(hcd_urb_list_lock); 109 110 /* used to protect against unlinking URBs after the device is gone */ 111 static DEFINE_SPINLOCK(hcd_urb_unlink_lock); 112 113 /* wait queue for synchronous unlinks */ 114 DECLARE_WAIT_QUEUE_HEAD(usb_kill_urb_queue); 115 116 static inline int is_root_hub(struct usb_device *udev) 117 { 118 return (udev->parent == NULL); 119 } 120 121 /*-------------------------------------------------------------------------*/ 122 123 /* 124 * Sharable chunks of root hub code. 125 */ 126 127 /*-------------------------------------------------------------------------*/ 128 #define KERNEL_REL bin2bcd(((LINUX_VERSION_CODE >> 16) & 0x0ff)) 129 #define KERNEL_VER bin2bcd(((LINUX_VERSION_CODE >> 8) & 0x0ff)) 130 131 /* usb 3.1 root hub device descriptor */ 132 static const u8 usb31_rh_dev_descriptor[18] = { 133 0x12, /* __u8 bLength; */ 134 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 135 0x10, 0x03, /* __le16 bcdUSB; v3.1 */ 136 137 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 138 0x00, /* __u8 bDeviceSubClass; */ 139 0x03, /* __u8 bDeviceProtocol; USB 3 hub */ 140 0x09, /* __u8 bMaxPacketSize0; 2^9 = 512 Bytes */ 141 142 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 143 0x03, 0x00, /* __le16 idProduct; device 0x0003 */ 144 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 145 146 0x03, /* __u8 iManufacturer; */ 147 0x02, /* __u8 iProduct; */ 148 0x01, /* __u8 iSerialNumber; */ 149 0x01 /* __u8 bNumConfigurations; */ 150 }; 151 152 /* usb 3.0 root hub device descriptor */ 153 static const u8 usb3_rh_dev_descriptor[18] = { 154 0x12, /* __u8 bLength; */ 155 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 156 0x00, 0x03, /* __le16 bcdUSB; v3.0 */ 157 158 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 159 0x00, /* __u8 bDeviceSubClass; */ 160 0x03, /* __u8 bDeviceProtocol; USB 3.0 hub */ 161 0x09, /* __u8 bMaxPacketSize0; 2^9 = 512 Bytes */ 162 163 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 164 0x03, 0x00, /* __le16 idProduct; device 0x0003 */ 165 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 166 167 0x03, /* __u8 iManufacturer; */ 168 0x02, /* __u8 iProduct; */ 169 0x01, /* __u8 iSerialNumber; */ 170 0x01 /* __u8 bNumConfigurations; */ 171 }; 172 173 /* usb 2.5 (wireless USB 1.0) root hub device descriptor */ 174 static const u8 usb25_rh_dev_descriptor[18] = { 175 0x12, /* __u8 bLength; */ 176 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 177 0x50, 0x02, /* __le16 bcdUSB; v2.5 */ 178 179 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 180 0x00, /* __u8 bDeviceSubClass; */ 181 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */ 182 0xFF, /* __u8 bMaxPacketSize0; always 0xFF (WUSB Spec 7.4.1). */ 183 184 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 185 0x02, 0x00, /* __le16 idProduct; device 0x0002 */ 186 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 187 188 0x03, /* __u8 iManufacturer; */ 189 0x02, /* __u8 iProduct; */ 190 0x01, /* __u8 iSerialNumber; */ 191 0x01 /* __u8 bNumConfigurations; */ 192 }; 193 194 /* usb 2.0 root hub device descriptor */ 195 static const u8 usb2_rh_dev_descriptor[18] = { 196 0x12, /* __u8 bLength; */ 197 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 198 0x00, 0x02, /* __le16 bcdUSB; v2.0 */ 199 200 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 201 0x00, /* __u8 bDeviceSubClass; */ 202 0x00, /* __u8 bDeviceProtocol; [ usb 2.0 no TT ] */ 203 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */ 204 205 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 206 0x02, 0x00, /* __le16 idProduct; device 0x0002 */ 207 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 208 209 0x03, /* __u8 iManufacturer; */ 210 0x02, /* __u8 iProduct; */ 211 0x01, /* __u8 iSerialNumber; */ 212 0x01 /* __u8 bNumConfigurations; */ 213 }; 214 215 /* no usb 2.0 root hub "device qualifier" descriptor: one speed only */ 216 217 /* usb 1.1 root hub device descriptor */ 218 static const u8 usb11_rh_dev_descriptor[18] = { 219 0x12, /* __u8 bLength; */ 220 USB_DT_DEVICE, /* __u8 bDescriptorType; Device */ 221 0x10, 0x01, /* __le16 bcdUSB; v1.1 */ 222 223 0x09, /* __u8 bDeviceClass; HUB_CLASSCODE */ 224 0x00, /* __u8 bDeviceSubClass; */ 225 0x00, /* __u8 bDeviceProtocol; [ low/full speeds only ] */ 226 0x40, /* __u8 bMaxPacketSize0; 64 Bytes */ 227 228 0x6b, 0x1d, /* __le16 idVendor; Linux Foundation 0x1d6b */ 229 0x01, 0x00, /* __le16 idProduct; device 0x0001 */ 230 KERNEL_VER, KERNEL_REL, /* __le16 bcdDevice */ 231 232 0x03, /* __u8 iManufacturer; */ 233 0x02, /* __u8 iProduct; */ 234 0x01, /* __u8 iSerialNumber; */ 235 0x01 /* __u8 bNumConfigurations; */ 236 }; 237 238 239 /*-------------------------------------------------------------------------*/ 240 241 /* Configuration descriptors for our root hubs */ 242 243 static const u8 fs_rh_config_descriptor[] = { 244 245 /* one configuration */ 246 0x09, /* __u8 bLength; */ 247 USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */ 248 0x19, 0x00, /* __le16 wTotalLength; */ 249 0x01, /* __u8 bNumInterfaces; (1) */ 250 0x01, /* __u8 bConfigurationValue; */ 251 0x00, /* __u8 iConfiguration; */ 252 0xc0, /* __u8 bmAttributes; 253 Bit 7: must be set, 254 6: Self-powered, 255 5: Remote wakeup, 256 4..0: resvd */ 257 0x00, /* __u8 MaxPower; */ 258 259 /* USB 1.1: 260 * USB 2.0, single TT organization (mandatory): 261 * one interface, protocol 0 262 * 263 * USB 2.0, multiple TT organization (optional): 264 * two interfaces, protocols 1 (like single TT) 265 * and 2 (multiple TT mode) ... config is 266 * sometimes settable 267 * NOT IMPLEMENTED 268 */ 269 270 /* one interface */ 271 0x09, /* __u8 if_bLength; */ 272 USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */ 273 0x00, /* __u8 if_bInterfaceNumber; */ 274 0x00, /* __u8 if_bAlternateSetting; */ 275 0x01, /* __u8 if_bNumEndpoints; */ 276 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ 277 0x00, /* __u8 if_bInterfaceSubClass; */ 278 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */ 279 0x00, /* __u8 if_iInterface; */ 280 281 /* one endpoint (status change endpoint) */ 282 0x07, /* __u8 ep_bLength; */ 283 USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 284 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 285 0x03, /* __u8 ep_bmAttributes; Interrupt */ 286 0x02, 0x00, /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) */ 287 0xff /* __u8 ep_bInterval; (255ms -- usb 2.0 spec) */ 288 }; 289 290 static const u8 hs_rh_config_descriptor[] = { 291 292 /* one configuration */ 293 0x09, /* __u8 bLength; */ 294 USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */ 295 0x19, 0x00, /* __le16 wTotalLength; */ 296 0x01, /* __u8 bNumInterfaces; (1) */ 297 0x01, /* __u8 bConfigurationValue; */ 298 0x00, /* __u8 iConfiguration; */ 299 0xc0, /* __u8 bmAttributes; 300 Bit 7: must be set, 301 6: Self-powered, 302 5: Remote wakeup, 303 4..0: resvd */ 304 0x00, /* __u8 MaxPower; */ 305 306 /* USB 1.1: 307 * USB 2.0, single TT organization (mandatory): 308 * one interface, protocol 0 309 * 310 * USB 2.0, multiple TT organization (optional): 311 * two interfaces, protocols 1 (like single TT) 312 * and 2 (multiple TT mode) ... config is 313 * sometimes settable 314 * NOT IMPLEMENTED 315 */ 316 317 /* one interface */ 318 0x09, /* __u8 if_bLength; */ 319 USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */ 320 0x00, /* __u8 if_bInterfaceNumber; */ 321 0x00, /* __u8 if_bAlternateSetting; */ 322 0x01, /* __u8 if_bNumEndpoints; */ 323 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ 324 0x00, /* __u8 if_bInterfaceSubClass; */ 325 0x00, /* __u8 if_bInterfaceProtocol; [usb1.1 or single tt] */ 326 0x00, /* __u8 if_iInterface; */ 327 328 /* one endpoint (status change endpoint) */ 329 0x07, /* __u8 ep_bLength; */ 330 USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 331 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 332 0x03, /* __u8 ep_bmAttributes; Interrupt */ 333 /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) 334 * see hub.c:hub_configure() for details. */ 335 (USB_MAXCHILDREN + 1 + 7) / 8, 0x00, 336 0x0c /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */ 337 }; 338 339 static const u8 ss_rh_config_descriptor[] = { 340 /* one configuration */ 341 0x09, /* __u8 bLength; */ 342 USB_DT_CONFIG, /* __u8 bDescriptorType; Configuration */ 343 0x1f, 0x00, /* __le16 wTotalLength; */ 344 0x01, /* __u8 bNumInterfaces; (1) */ 345 0x01, /* __u8 bConfigurationValue; */ 346 0x00, /* __u8 iConfiguration; */ 347 0xc0, /* __u8 bmAttributes; 348 Bit 7: must be set, 349 6: Self-powered, 350 5: Remote wakeup, 351 4..0: resvd */ 352 0x00, /* __u8 MaxPower; */ 353 354 /* one interface */ 355 0x09, /* __u8 if_bLength; */ 356 USB_DT_INTERFACE, /* __u8 if_bDescriptorType; Interface */ 357 0x00, /* __u8 if_bInterfaceNumber; */ 358 0x00, /* __u8 if_bAlternateSetting; */ 359 0x01, /* __u8 if_bNumEndpoints; */ 360 0x09, /* __u8 if_bInterfaceClass; HUB_CLASSCODE */ 361 0x00, /* __u8 if_bInterfaceSubClass; */ 362 0x00, /* __u8 if_bInterfaceProtocol; */ 363 0x00, /* __u8 if_iInterface; */ 364 365 /* one endpoint (status change endpoint) */ 366 0x07, /* __u8 ep_bLength; */ 367 USB_DT_ENDPOINT, /* __u8 ep_bDescriptorType; Endpoint */ 368 0x81, /* __u8 ep_bEndpointAddress; IN Endpoint 1 */ 369 0x03, /* __u8 ep_bmAttributes; Interrupt */ 370 /* __le16 ep_wMaxPacketSize; 1 + (MAX_ROOT_PORTS / 8) 371 * see hub.c:hub_configure() for details. */ 372 (USB_MAXCHILDREN + 1 + 7) / 8, 0x00, 373 0x0c, /* __u8 ep_bInterval; (256ms -- usb 2.0 spec) */ 374 375 /* one SuperSpeed endpoint companion descriptor */ 376 0x06, /* __u8 ss_bLength */ 377 USB_DT_SS_ENDPOINT_COMP, /* __u8 ss_bDescriptorType; SuperSpeed EP */ 378 /* Companion */ 379 0x00, /* __u8 ss_bMaxBurst; allows 1 TX between ACKs */ 380 0x00, /* __u8 ss_bmAttributes; 1 packet per service interval */ 381 0x02, 0x00 /* __le16 ss_wBytesPerInterval; 15 bits for max 15 ports */ 382 }; 383 384 /* authorized_default behaviour: 385 * -1 is authorized for all devices except wireless (old behaviour) 386 * 0 is unauthorized for all devices 387 * 1 is authorized for all devices 388 */ 389 static int authorized_default = -1; 390 module_param(authorized_default, int, S_IRUGO|S_IWUSR); 391 MODULE_PARM_DESC(authorized_default, 392 "Default USB device authorization: 0 is not authorized, 1 is " 393 "authorized, -1 is authorized except for wireless USB (default, " 394 "old behaviour"); 395 /*-------------------------------------------------------------------------*/ 396 397 /** 398 * ascii2desc() - Helper routine for producing UTF-16LE string descriptors 399 * @s: Null-terminated ASCII (actually ISO-8859-1) string 400 * @buf: Buffer for USB string descriptor (header + UTF-16LE) 401 * @len: Length (in bytes; may be odd) of descriptor buffer. 402 * 403 * Return: The number of bytes filled in: 2 + 2*strlen(s) or @len, 404 * whichever is less. 405 * 406 * Note: 407 * USB String descriptors can contain at most 126 characters; input 408 * strings longer than that are truncated. 409 */ 410 static unsigned 411 ascii2desc(char const *s, u8 *buf, unsigned len) 412 { 413 unsigned n, t = 2 + 2*strlen(s); 414 415 if (t > 254) 416 t = 254; /* Longest possible UTF string descriptor */ 417 if (len > t) 418 len = t; 419 420 t += USB_DT_STRING << 8; /* Now t is first 16 bits to store */ 421 422 n = len; 423 while (n--) { 424 *buf++ = t; 425 if (!n--) 426 break; 427 *buf++ = t >> 8; 428 t = (unsigned char)*s++; 429 } 430 return len; 431 } 432 433 /** 434 * rh_string() - provides string descriptors for root hub 435 * @id: the string ID number (0: langids, 1: serial #, 2: product, 3: vendor) 436 * @hcd: the host controller for this root hub 437 * @data: buffer for output packet 438 * @len: length of the provided buffer 439 * 440 * Produces either a manufacturer, product or serial number string for the 441 * virtual root hub device. 442 * 443 * Return: The number of bytes filled in: the length of the descriptor or 444 * of the provided buffer, whichever is less. 445 */ 446 static unsigned 447 rh_string(int id, struct usb_hcd const *hcd, u8 *data, unsigned len) 448 { 449 char buf[100]; 450 char const *s; 451 static char const langids[4] = {4, USB_DT_STRING, 0x09, 0x04}; 452 453 /* language ids */ 454 switch (id) { 455 case 0: 456 /* Array of LANGID codes (0x0409 is MSFT-speak for "en-us") */ 457 /* See http://www.usb.org/developers/docs/USB_LANGIDs.pdf */ 458 if (len > 4) 459 len = 4; 460 memcpy(data, langids, len); 461 return len; 462 case 1: 463 /* Serial number */ 464 s = hcd->self.bus_name; 465 break; 466 case 2: 467 /* Product name */ 468 s = hcd->product_desc; 469 break; 470 case 3: 471 /* Manufacturer */ 472 snprintf (buf, sizeof buf, "%s %s %s", init_utsname()->sysname, 473 init_utsname()->release, hcd->driver->description); 474 s = buf; 475 break; 476 default: 477 /* Can't happen; caller guarantees it */ 478 return 0; 479 } 480 481 return ascii2desc(s, data, len); 482 } 483 484 485 /* Root hub control transfers execute synchronously */ 486 static int rh_call_control (struct usb_hcd *hcd, struct urb *urb) 487 { 488 struct usb_ctrlrequest *cmd; 489 u16 typeReq, wValue, wIndex, wLength; 490 u8 *ubuf = urb->transfer_buffer; 491 unsigned len = 0; 492 int status; 493 u8 patch_wakeup = 0; 494 u8 patch_protocol = 0; 495 u16 tbuf_size; 496 u8 *tbuf = NULL; 497 const u8 *bufp; 498 499 might_sleep(); 500 501 spin_lock_irq(&hcd_root_hub_lock); 502 status = usb_hcd_link_urb_to_ep(hcd, urb); 503 spin_unlock_irq(&hcd_root_hub_lock); 504 if (status) 505 return status; 506 urb->hcpriv = hcd; /* Indicate it's queued */ 507 508 cmd = (struct usb_ctrlrequest *) urb->setup_packet; 509 typeReq = (cmd->bRequestType << 8) | cmd->bRequest; 510 wValue = le16_to_cpu (cmd->wValue); 511 wIndex = le16_to_cpu (cmd->wIndex); 512 wLength = le16_to_cpu (cmd->wLength); 513 514 if (wLength > urb->transfer_buffer_length) 515 goto error; 516 517 /* 518 * tbuf should be at least as big as the 519 * USB hub descriptor. 520 */ 521 tbuf_size = max_t(u16, sizeof(struct usb_hub_descriptor), wLength); 522 tbuf = kzalloc(tbuf_size, GFP_KERNEL); 523 if (!tbuf) { 524 status = -ENOMEM; 525 goto err_alloc; 526 } 527 528 bufp = tbuf; 529 530 531 urb->actual_length = 0; 532 switch (typeReq) { 533 534 /* DEVICE REQUESTS */ 535 536 /* The root hub's remote wakeup enable bit is implemented using 537 * driver model wakeup flags. If this system supports wakeup 538 * through USB, userspace may change the default "allow wakeup" 539 * policy through sysfs or these calls. 540 * 541 * Most root hubs support wakeup from downstream devices, for 542 * runtime power management (disabling USB clocks and reducing 543 * VBUS power usage). However, not all of them do so; silicon, 544 * board, and BIOS bugs here are not uncommon, so these can't 545 * be treated quite like external hubs. 546 * 547 * Likewise, not all root hubs will pass wakeup events upstream, 548 * to wake up the whole system. So don't assume root hub and 549 * controller capabilities are identical. 550 */ 551 552 case DeviceRequest | USB_REQ_GET_STATUS: 553 tbuf[0] = (device_may_wakeup(&hcd->self.root_hub->dev) 554 << USB_DEVICE_REMOTE_WAKEUP) 555 | (1 << USB_DEVICE_SELF_POWERED); 556 tbuf[1] = 0; 557 len = 2; 558 break; 559 case DeviceOutRequest | USB_REQ_CLEAR_FEATURE: 560 if (wValue == USB_DEVICE_REMOTE_WAKEUP) 561 device_set_wakeup_enable(&hcd->self.root_hub->dev, 0); 562 else 563 goto error; 564 break; 565 case DeviceOutRequest | USB_REQ_SET_FEATURE: 566 if (device_can_wakeup(&hcd->self.root_hub->dev) 567 && wValue == USB_DEVICE_REMOTE_WAKEUP) 568 device_set_wakeup_enable(&hcd->self.root_hub->dev, 1); 569 else 570 goto error; 571 break; 572 case DeviceRequest | USB_REQ_GET_CONFIGURATION: 573 tbuf[0] = 1; 574 len = 1; 575 /* FALLTHROUGH */ 576 case DeviceOutRequest | USB_REQ_SET_CONFIGURATION: 577 break; 578 case DeviceRequest | USB_REQ_GET_DESCRIPTOR: 579 switch (wValue & 0xff00) { 580 case USB_DT_DEVICE << 8: 581 switch (hcd->speed) { 582 case HCD_USB31: 583 bufp = usb31_rh_dev_descriptor; 584 break; 585 case HCD_USB3: 586 bufp = usb3_rh_dev_descriptor; 587 break; 588 case HCD_USB25: 589 bufp = usb25_rh_dev_descriptor; 590 break; 591 case HCD_USB2: 592 bufp = usb2_rh_dev_descriptor; 593 break; 594 case HCD_USB11: 595 bufp = usb11_rh_dev_descriptor; 596 break; 597 default: 598 goto error; 599 } 600 len = 18; 601 if (hcd->has_tt) 602 patch_protocol = 1; 603 break; 604 case USB_DT_CONFIG << 8: 605 switch (hcd->speed) { 606 case HCD_USB31: 607 case HCD_USB3: 608 bufp = ss_rh_config_descriptor; 609 len = sizeof ss_rh_config_descriptor; 610 break; 611 case HCD_USB25: 612 case HCD_USB2: 613 bufp = hs_rh_config_descriptor; 614 len = sizeof hs_rh_config_descriptor; 615 break; 616 case HCD_USB11: 617 bufp = fs_rh_config_descriptor; 618 len = sizeof fs_rh_config_descriptor; 619 break; 620 default: 621 goto error; 622 } 623 if (device_can_wakeup(&hcd->self.root_hub->dev)) 624 patch_wakeup = 1; 625 break; 626 case USB_DT_STRING << 8: 627 if ((wValue & 0xff) < 4) 628 urb->actual_length = rh_string(wValue & 0xff, 629 hcd, ubuf, wLength); 630 else /* unsupported IDs --> "protocol stall" */ 631 goto error; 632 break; 633 case USB_DT_BOS << 8: 634 goto nongeneric; 635 default: 636 goto error; 637 } 638 break; 639 case DeviceRequest | USB_REQ_GET_INTERFACE: 640 tbuf[0] = 0; 641 len = 1; 642 /* FALLTHROUGH */ 643 case DeviceOutRequest | USB_REQ_SET_INTERFACE: 644 break; 645 case DeviceOutRequest | USB_REQ_SET_ADDRESS: 646 /* wValue == urb->dev->devaddr */ 647 dev_dbg (hcd->self.controller, "root hub device address %d\n", 648 wValue); 649 break; 650 651 /* INTERFACE REQUESTS (no defined feature/status flags) */ 652 653 /* ENDPOINT REQUESTS */ 654 655 case EndpointRequest | USB_REQ_GET_STATUS: 656 /* ENDPOINT_HALT flag */ 657 tbuf[0] = 0; 658 tbuf[1] = 0; 659 len = 2; 660 /* FALLTHROUGH */ 661 case EndpointOutRequest | USB_REQ_CLEAR_FEATURE: 662 case EndpointOutRequest | USB_REQ_SET_FEATURE: 663 dev_dbg (hcd->self.controller, "no endpoint features yet\n"); 664 break; 665 666 /* CLASS REQUESTS (and errors) */ 667 668 default: 669 nongeneric: 670 /* non-generic request */ 671 switch (typeReq) { 672 case GetHubStatus: 673 len = 4; 674 break; 675 case GetPortStatus: 676 if (wValue == HUB_PORT_STATUS) 677 len = 4; 678 else 679 /* other port status types return 8 bytes */ 680 len = 8; 681 break; 682 case GetHubDescriptor: 683 len = sizeof (struct usb_hub_descriptor); 684 break; 685 case DeviceRequest | USB_REQ_GET_DESCRIPTOR: 686 /* len is returned by hub_control */ 687 break; 688 } 689 status = hcd->driver->hub_control (hcd, 690 typeReq, wValue, wIndex, 691 tbuf, wLength); 692 693 if (typeReq == GetHubDescriptor) 694 usb_hub_adjust_deviceremovable(hcd->self.root_hub, 695 (struct usb_hub_descriptor *)tbuf); 696 break; 697 error: 698 /* "protocol stall" on error */ 699 status = -EPIPE; 700 } 701 702 if (status < 0) { 703 len = 0; 704 if (status != -EPIPE) { 705 dev_dbg (hcd->self.controller, 706 "CTRL: TypeReq=0x%x val=0x%x " 707 "idx=0x%x len=%d ==> %d\n", 708 typeReq, wValue, wIndex, 709 wLength, status); 710 } 711 } else if (status > 0) { 712 /* hub_control may return the length of data copied. */ 713 len = status; 714 status = 0; 715 } 716 if (len) { 717 if (urb->transfer_buffer_length < len) 718 len = urb->transfer_buffer_length; 719 urb->actual_length = len; 720 /* always USB_DIR_IN, toward host */ 721 memcpy (ubuf, bufp, len); 722 723 /* report whether RH hardware supports remote wakeup */ 724 if (patch_wakeup && 725 len > offsetof (struct usb_config_descriptor, 726 bmAttributes)) 727 ((struct usb_config_descriptor *)ubuf)->bmAttributes 728 |= USB_CONFIG_ATT_WAKEUP; 729 730 /* report whether RH hardware has an integrated TT */ 731 if (patch_protocol && 732 len > offsetof(struct usb_device_descriptor, 733 bDeviceProtocol)) 734 ((struct usb_device_descriptor *) ubuf)-> 735 bDeviceProtocol = USB_HUB_PR_HS_SINGLE_TT; 736 } 737 738 kfree(tbuf); 739 err_alloc: 740 741 /* any errors get returned through the urb completion */ 742 spin_lock_irq(&hcd_root_hub_lock); 743 usb_hcd_unlink_urb_from_ep(hcd, urb); 744 usb_hcd_giveback_urb(hcd, urb, status); 745 spin_unlock_irq(&hcd_root_hub_lock); 746 return 0; 747 } 748 749 /*-------------------------------------------------------------------------*/ 750 751 /* 752 * Root Hub interrupt transfers are polled using a timer if the 753 * driver requests it; otherwise the driver is responsible for 754 * calling usb_hcd_poll_rh_status() when an event occurs. 755 * 756 * Completions are called in_interrupt(), but they may or may not 757 * be in_irq(). 758 */ 759 void usb_hcd_poll_rh_status(struct usb_hcd *hcd) 760 { 761 struct urb *urb; 762 int length; 763 unsigned long flags; 764 char buffer[6]; /* Any root hubs with > 31 ports? */ 765 766 if (unlikely(!hcd->rh_pollable)) 767 return; 768 if (!hcd->uses_new_polling && !hcd->status_urb) 769 return; 770 771 length = hcd->driver->hub_status_data(hcd, buffer); 772 if (length > 0) { 773 774 /* try to complete the status urb */ 775 spin_lock_irqsave(&hcd_root_hub_lock, flags); 776 urb = hcd->status_urb; 777 if (urb) { 778 clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags); 779 hcd->status_urb = NULL; 780 urb->actual_length = length; 781 memcpy(urb->transfer_buffer, buffer, length); 782 783 usb_hcd_unlink_urb_from_ep(hcd, urb); 784 usb_hcd_giveback_urb(hcd, urb, 0); 785 } else { 786 length = 0; 787 set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags); 788 } 789 spin_unlock_irqrestore(&hcd_root_hub_lock, flags); 790 } 791 792 /* The USB 2.0 spec says 256 ms. This is close enough and won't 793 * exceed that limit if HZ is 100. The math is more clunky than 794 * maybe expected, this is to make sure that all timers for USB devices 795 * fire at the same time to give the CPU a break in between */ 796 if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) : 797 (length == 0 && hcd->status_urb != NULL)) 798 mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4)); 799 } 800 EXPORT_SYMBOL_GPL(usb_hcd_poll_rh_status); 801 802 /* timer callback */ 803 static void rh_timer_func (unsigned long _hcd) 804 { 805 usb_hcd_poll_rh_status((struct usb_hcd *) _hcd); 806 } 807 808 /*-------------------------------------------------------------------------*/ 809 810 static int rh_queue_status (struct usb_hcd *hcd, struct urb *urb) 811 { 812 int retval; 813 unsigned long flags; 814 unsigned len = 1 + (urb->dev->maxchild / 8); 815 816 spin_lock_irqsave (&hcd_root_hub_lock, flags); 817 if (hcd->status_urb || urb->transfer_buffer_length < len) { 818 dev_dbg (hcd->self.controller, "not queuing rh status urb\n"); 819 retval = -EINVAL; 820 goto done; 821 } 822 823 retval = usb_hcd_link_urb_to_ep(hcd, urb); 824 if (retval) 825 goto done; 826 827 hcd->status_urb = urb; 828 urb->hcpriv = hcd; /* indicate it's queued */ 829 if (!hcd->uses_new_polling) 830 mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4)); 831 832 /* If a status change has already occurred, report it ASAP */ 833 else if (HCD_POLL_PENDING(hcd)) 834 mod_timer(&hcd->rh_timer, jiffies); 835 retval = 0; 836 done: 837 spin_unlock_irqrestore (&hcd_root_hub_lock, flags); 838 return retval; 839 } 840 841 static int rh_urb_enqueue (struct usb_hcd *hcd, struct urb *urb) 842 { 843 if (usb_endpoint_xfer_int(&urb->ep->desc)) 844 return rh_queue_status (hcd, urb); 845 if (usb_endpoint_xfer_control(&urb->ep->desc)) 846 return rh_call_control (hcd, urb); 847 return -EINVAL; 848 } 849 850 /*-------------------------------------------------------------------------*/ 851 852 /* Unlinks of root-hub control URBs are legal, but they don't do anything 853 * since these URBs always execute synchronously. 854 */ 855 static int usb_rh_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status) 856 { 857 unsigned long flags; 858 int rc; 859 860 spin_lock_irqsave(&hcd_root_hub_lock, flags); 861 rc = usb_hcd_check_unlink_urb(hcd, urb, status); 862 if (rc) 863 goto done; 864 865 if (usb_endpoint_num(&urb->ep->desc) == 0) { /* Control URB */ 866 ; /* Do nothing */ 867 868 } else { /* Status URB */ 869 if (!hcd->uses_new_polling) 870 del_timer (&hcd->rh_timer); 871 if (urb == hcd->status_urb) { 872 hcd->status_urb = NULL; 873 usb_hcd_unlink_urb_from_ep(hcd, urb); 874 usb_hcd_giveback_urb(hcd, urb, status); 875 } 876 } 877 done: 878 spin_unlock_irqrestore(&hcd_root_hub_lock, flags); 879 return rc; 880 } 881 882 883 884 /* 885 * Show & store the current value of authorized_default 886 */ 887 static ssize_t authorized_default_show(struct device *dev, 888 struct device_attribute *attr, char *buf) 889 { 890 struct usb_device *rh_usb_dev = to_usb_device(dev); 891 struct usb_bus *usb_bus = rh_usb_dev->bus; 892 struct usb_hcd *hcd; 893 894 hcd = bus_to_hcd(usb_bus); 895 return snprintf(buf, PAGE_SIZE, "%u\n", !!HCD_DEV_AUTHORIZED(hcd)); 896 } 897 898 static ssize_t authorized_default_store(struct device *dev, 899 struct device_attribute *attr, 900 const char *buf, size_t size) 901 { 902 ssize_t result; 903 unsigned val; 904 struct usb_device *rh_usb_dev = to_usb_device(dev); 905 struct usb_bus *usb_bus = rh_usb_dev->bus; 906 struct usb_hcd *hcd; 907 908 hcd = bus_to_hcd(usb_bus); 909 result = sscanf(buf, "%u\n", &val); 910 if (result == 1) { 911 if (val) 912 set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 913 else 914 clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 915 916 result = size; 917 } else { 918 result = -EINVAL; 919 } 920 return result; 921 } 922 static DEVICE_ATTR_RW(authorized_default); 923 924 /* 925 * interface_authorized_default_show - show default authorization status 926 * for USB interfaces 927 * 928 * note: interface_authorized_default is the default value 929 * for initializing the authorized attribute of interfaces 930 */ 931 static ssize_t interface_authorized_default_show(struct device *dev, 932 struct device_attribute *attr, char *buf) 933 { 934 struct usb_device *usb_dev = to_usb_device(dev); 935 struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus); 936 937 return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd)); 938 } 939 940 /* 941 * interface_authorized_default_store - store default authorization status 942 * for USB interfaces 943 * 944 * note: interface_authorized_default is the default value 945 * for initializing the authorized attribute of interfaces 946 */ 947 static ssize_t interface_authorized_default_store(struct device *dev, 948 struct device_attribute *attr, const char *buf, size_t count) 949 { 950 struct usb_device *usb_dev = to_usb_device(dev); 951 struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus); 952 int rc = count; 953 bool val; 954 955 if (strtobool(buf, &val) != 0) 956 return -EINVAL; 957 958 if (val) 959 set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); 960 else 961 clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); 962 963 return rc; 964 } 965 static DEVICE_ATTR_RW(interface_authorized_default); 966 967 /* Group all the USB bus attributes */ 968 static struct attribute *usb_bus_attrs[] = { 969 &dev_attr_authorized_default.attr, 970 &dev_attr_interface_authorized_default.attr, 971 NULL, 972 }; 973 974 static struct attribute_group usb_bus_attr_group = { 975 .name = NULL, /* we want them in the same directory */ 976 .attrs = usb_bus_attrs, 977 }; 978 979 980 981 /*-------------------------------------------------------------------------*/ 982 983 /** 984 * usb_bus_init - shared initialization code 985 * @bus: the bus structure being initialized 986 * 987 * This code is used to initialize a usb_bus structure, memory for which is 988 * separately managed. 989 */ 990 static void usb_bus_init (struct usb_bus *bus) 991 { 992 memset (&bus->devmap, 0, sizeof(struct usb_devmap)); 993 994 bus->devnum_next = 1; 995 996 bus->root_hub = NULL; 997 bus->busnum = -1; 998 bus->bandwidth_allocated = 0; 999 bus->bandwidth_int_reqs = 0; 1000 bus->bandwidth_isoc_reqs = 0; 1001 mutex_init(&bus->devnum_next_mutex); 1002 } 1003 1004 /*-------------------------------------------------------------------------*/ 1005 1006 /** 1007 * usb_register_bus - registers the USB host controller with the usb core 1008 * @bus: pointer to the bus to register 1009 * Context: !in_interrupt() 1010 * 1011 * Assigns a bus number, and links the controller into usbcore data 1012 * structures so that it can be seen by scanning the bus list. 1013 * 1014 * Return: 0 if successful. A negative error code otherwise. 1015 */ 1016 static int usb_register_bus(struct usb_bus *bus) 1017 { 1018 int result = -E2BIG; 1019 int busnum; 1020 1021 mutex_lock(&usb_bus_idr_lock); 1022 busnum = idr_alloc(&usb_bus_idr, bus, 1, USB_MAXBUS, GFP_KERNEL); 1023 if (busnum < 0) { 1024 pr_err("%s: failed to get bus number\n", usbcore_name); 1025 goto error_find_busnum; 1026 } 1027 bus->busnum = busnum; 1028 mutex_unlock(&usb_bus_idr_lock); 1029 1030 usb_notify_add_bus(bus); 1031 1032 dev_info (bus->controller, "new USB bus registered, assigned bus " 1033 "number %d\n", bus->busnum); 1034 return 0; 1035 1036 error_find_busnum: 1037 mutex_unlock(&usb_bus_idr_lock); 1038 return result; 1039 } 1040 1041 /** 1042 * usb_deregister_bus - deregisters the USB host controller 1043 * @bus: pointer to the bus to deregister 1044 * Context: !in_interrupt() 1045 * 1046 * Recycles the bus number, and unlinks the controller from usbcore data 1047 * structures so that it won't be seen by scanning the bus list. 1048 */ 1049 static void usb_deregister_bus (struct usb_bus *bus) 1050 { 1051 dev_info (bus->controller, "USB bus %d deregistered\n", bus->busnum); 1052 1053 /* 1054 * NOTE: make sure that all the devices are removed by the 1055 * controller code, as well as having it call this when cleaning 1056 * itself up 1057 */ 1058 mutex_lock(&usb_bus_idr_lock); 1059 idr_remove(&usb_bus_idr, bus->busnum); 1060 mutex_unlock(&usb_bus_idr_lock); 1061 1062 usb_notify_remove_bus(bus); 1063 } 1064 1065 /** 1066 * register_root_hub - called by usb_add_hcd() to register a root hub 1067 * @hcd: host controller for this root hub 1068 * 1069 * This function registers the root hub with the USB subsystem. It sets up 1070 * the device properly in the device tree and then calls usb_new_device() 1071 * to register the usb device. It also assigns the root hub's USB address 1072 * (always 1). 1073 * 1074 * Return: 0 if successful. A negative error code otherwise. 1075 */ 1076 static int register_root_hub(struct usb_hcd *hcd) 1077 { 1078 struct device *parent_dev = hcd->self.controller; 1079 struct usb_device *usb_dev = hcd->self.root_hub; 1080 const int devnum = 1; 1081 int retval; 1082 1083 usb_dev->devnum = devnum; 1084 usb_dev->bus->devnum_next = devnum + 1; 1085 memset (&usb_dev->bus->devmap.devicemap, 0, 1086 sizeof usb_dev->bus->devmap.devicemap); 1087 set_bit (devnum, usb_dev->bus->devmap.devicemap); 1088 usb_set_device_state(usb_dev, USB_STATE_ADDRESS); 1089 1090 mutex_lock(&usb_bus_idr_lock); 1091 1092 usb_dev->ep0.desc.wMaxPacketSize = cpu_to_le16(64); 1093 retval = usb_get_device_descriptor(usb_dev, USB_DT_DEVICE_SIZE); 1094 if (retval != sizeof usb_dev->descriptor) { 1095 mutex_unlock(&usb_bus_idr_lock); 1096 dev_dbg (parent_dev, "can't read %s device descriptor %d\n", 1097 dev_name(&usb_dev->dev), retval); 1098 return (retval < 0) ? retval : -EMSGSIZE; 1099 } 1100 1101 if (le16_to_cpu(usb_dev->descriptor.bcdUSB) >= 0x0201) { 1102 retval = usb_get_bos_descriptor(usb_dev); 1103 if (!retval) { 1104 usb_dev->lpm_capable = usb_device_supports_lpm(usb_dev); 1105 } else if (usb_dev->speed >= USB_SPEED_SUPER) { 1106 mutex_unlock(&usb_bus_idr_lock); 1107 dev_dbg(parent_dev, "can't read %s bos descriptor %d\n", 1108 dev_name(&usb_dev->dev), retval); 1109 return retval; 1110 } 1111 } 1112 1113 retval = usb_new_device (usb_dev); 1114 if (retval) { 1115 dev_err (parent_dev, "can't register root hub for %s, %d\n", 1116 dev_name(&usb_dev->dev), retval); 1117 } else { 1118 spin_lock_irq (&hcd_root_hub_lock); 1119 hcd->rh_registered = 1; 1120 spin_unlock_irq (&hcd_root_hub_lock); 1121 1122 /* Did the HC die before the root hub was registered? */ 1123 if (HCD_DEAD(hcd)) 1124 usb_hc_died (hcd); /* This time clean up */ 1125 usb_dev->dev.of_node = parent_dev->of_node; 1126 } 1127 mutex_unlock(&usb_bus_idr_lock); 1128 1129 return retval; 1130 } 1131 1132 /* 1133 * usb_hcd_start_port_resume - a root-hub port is sending a resume signal 1134 * @bus: the bus which the root hub belongs to 1135 * @portnum: the port which is being resumed 1136 * 1137 * HCDs should call this function when they know that a resume signal is 1138 * being sent to a root-hub port. The root hub will be prevented from 1139 * going into autosuspend until usb_hcd_end_port_resume() is called. 1140 * 1141 * The bus's private lock must be held by the caller. 1142 */ 1143 void usb_hcd_start_port_resume(struct usb_bus *bus, int portnum) 1144 { 1145 unsigned bit = 1 << portnum; 1146 1147 if (!(bus->resuming_ports & bit)) { 1148 bus->resuming_ports |= bit; 1149 pm_runtime_get_noresume(&bus->root_hub->dev); 1150 } 1151 } 1152 EXPORT_SYMBOL_GPL(usb_hcd_start_port_resume); 1153 1154 /* 1155 * usb_hcd_end_port_resume - a root-hub port has stopped sending a resume signal 1156 * @bus: the bus which the root hub belongs to 1157 * @portnum: the port which is being resumed 1158 * 1159 * HCDs should call this function when they know that a resume signal has 1160 * stopped being sent to a root-hub port. The root hub will be allowed to 1161 * autosuspend again. 1162 * 1163 * The bus's private lock must be held by the caller. 1164 */ 1165 void usb_hcd_end_port_resume(struct usb_bus *bus, int portnum) 1166 { 1167 unsigned bit = 1 << portnum; 1168 1169 if (bus->resuming_ports & bit) { 1170 bus->resuming_ports &= ~bit; 1171 pm_runtime_put_noidle(&bus->root_hub->dev); 1172 } 1173 } 1174 EXPORT_SYMBOL_GPL(usb_hcd_end_port_resume); 1175 1176 /*-------------------------------------------------------------------------*/ 1177 1178 /** 1179 * usb_calc_bus_time - approximate periodic transaction time in nanoseconds 1180 * @speed: from dev->speed; USB_SPEED_{LOW,FULL,HIGH} 1181 * @is_input: true iff the transaction sends data to the host 1182 * @isoc: true for isochronous transactions, false for interrupt ones 1183 * @bytecount: how many bytes in the transaction. 1184 * 1185 * Return: Approximate bus time in nanoseconds for a periodic transaction. 1186 * 1187 * Note: 1188 * See USB 2.0 spec section 5.11.3; only periodic transfers need to be 1189 * scheduled in software, this function is only used for such scheduling. 1190 */ 1191 long usb_calc_bus_time (int speed, int is_input, int isoc, int bytecount) 1192 { 1193 unsigned long tmp; 1194 1195 switch (speed) { 1196 case USB_SPEED_LOW: /* INTR only */ 1197 if (is_input) { 1198 tmp = (67667L * (31L + 10L * BitTime (bytecount))) / 1000L; 1199 return 64060L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp; 1200 } else { 1201 tmp = (66700L * (31L + 10L * BitTime (bytecount))) / 1000L; 1202 return 64107L + (2 * BW_HUB_LS_SETUP) + BW_HOST_DELAY + tmp; 1203 } 1204 case USB_SPEED_FULL: /* ISOC or INTR */ 1205 if (isoc) { 1206 tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L; 1207 return ((is_input) ? 7268L : 6265L) + BW_HOST_DELAY + tmp; 1208 } else { 1209 tmp = (8354L * (31L + 10L * BitTime (bytecount))) / 1000L; 1210 return 9107L + BW_HOST_DELAY + tmp; 1211 } 1212 case USB_SPEED_HIGH: /* ISOC or INTR */ 1213 /* FIXME adjust for input vs output */ 1214 if (isoc) 1215 tmp = HS_NSECS_ISO (bytecount); 1216 else 1217 tmp = HS_NSECS (bytecount); 1218 return tmp; 1219 default: 1220 pr_debug ("%s: bogus device speed!\n", usbcore_name); 1221 return -1; 1222 } 1223 } 1224 EXPORT_SYMBOL_GPL(usb_calc_bus_time); 1225 1226 1227 /*-------------------------------------------------------------------------*/ 1228 1229 /* 1230 * Generic HC operations. 1231 */ 1232 1233 /*-------------------------------------------------------------------------*/ 1234 1235 /** 1236 * usb_hcd_link_urb_to_ep - add an URB to its endpoint queue 1237 * @hcd: host controller to which @urb was submitted 1238 * @urb: URB being submitted 1239 * 1240 * Host controller drivers should call this routine in their enqueue() 1241 * method. The HCD's private spinlock must be held and interrupts must 1242 * be disabled. The actions carried out here are required for URB 1243 * submission, as well as for endpoint shutdown and for usb_kill_urb. 1244 * 1245 * Return: 0 for no error, otherwise a negative error code (in which case 1246 * the enqueue() method must fail). If no error occurs but enqueue() fails 1247 * anyway, it must call usb_hcd_unlink_urb_from_ep() before releasing 1248 * the private spinlock and returning. 1249 */ 1250 int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb) 1251 { 1252 int rc = 0; 1253 1254 spin_lock(&hcd_urb_list_lock); 1255 1256 /* Check that the URB isn't being killed */ 1257 if (unlikely(atomic_read(&urb->reject))) { 1258 rc = -EPERM; 1259 goto done; 1260 } 1261 1262 if (unlikely(!urb->ep->enabled)) { 1263 rc = -ENOENT; 1264 goto done; 1265 } 1266 1267 if (unlikely(!urb->dev->can_submit)) { 1268 rc = -EHOSTUNREACH; 1269 goto done; 1270 } 1271 1272 /* 1273 * Check the host controller's state and add the URB to the 1274 * endpoint's queue. 1275 */ 1276 if (HCD_RH_RUNNING(hcd)) { 1277 urb->unlinked = 0; 1278 list_add_tail(&urb->urb_list, &urb->ep->urb_list); 1279 } else { 1280 rc = -ESHUTDOWN; 1281 goto done; 1282 } 1283 done: 1284 spin_unlock(&hcd_urb_list_lock); 1285 return rc; 1286 } 1287 EXPORT_SYMBOL_GPL(usb_hcd_link_urb_to_ep); 1288 1289 /** 1290 * usb_hcd_check_unlink_urb - check whether an URB may be unlinked 1291 * @hcd: host controller to which @urb was submitted 1292 * @urb: URB being checked for unlinkability 1293 * @status: error code to store in @urb if the unlink succeeds 1294 * 1295 * Host controller drivers should call this routine in their dequeue() 1296 * method. The HCD's private spinlock must be held and interrupts must 1297 * be disabled. The actions carried out here are required for making 1298 * sure than an unlink is valid. 1299 * 1300 * Return: 0 for no error, otherwise a negative error code (in which case 1301 * the dequeue() method must fail). The possible error codes are: 1302 * 1303 * -EIDRM: @urb was not submitted or has already completed. 1304 * The completion function may not have been called yet. 1305 * 1306 * -EBUSY: @urb has already been unlinked. 1307 */ 1308 int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb, 1309 int status) 1310 { 1311 struct list_head *tmp; 1312 1313 /* insist the urb is still queued */ 1314 list_for_each(tmp, &urb->ep->urb_list) { 1315 if (tmp == &urb->urb_list) 1316 break; 1317 } 1318 if (tmp != &urb->urb_list) 1319 return -EIDRM; 1320 1321 /* Any status except -EINPROGRESS means something already started to 1322 * unlink this URB from the hardware. So there's no more work to do. 1323 */ 1324 if (urb->unlinked) 1325 return -EBUSY; 1326 urb->unlinked = status; 1327 return 0; 1328 } 1329 EXPORT_SYMBOL_GPL(usb_hcd_check_unlink_urb); 1330 1331 /** 1332 * usb_hcd_unlink_urb_from_ep - remove an URB from its endpoint queue 1333 * @hcd: host controller to which @urb was submitted 1334 * @urb: URB being unlinked 1335 * 1336 * Host controller drivers should call this routine before calling 1337 * usb_hcd_giveback_urb(). The HCD's private spinlock must be held and 1338 * interrupts must be disabled. The actions carried out here are required 1339 * for URB completion. 1340 */ 1341 void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb) 1342 { 1343 /* clear all state linking urb to this dev (and hcd) */ 1344 spin_lock(&hcd_urb_list_lock); 1345 list_del_init(&urb->urb_list); 1346 spin_unlock(&hcd_urb_list_lock); 1347 } 1348 EXPORT_SYMBOL_GPL(usb_hcd_unlink_urb_from_ep); 1349 1350 /* 1351 * Some usb host controllers can only perform dma using a small SRAM area. 1352 * The usb core itself is however optimized for host controllers that can dma 1353 * using regular system memory - like pci devices doing bus mastering. 1354 * 1355 * To support host controllers with limited dma capabilities we provide dma 1356 * bounce buffers. This feature can be enabled using the HCD_LOCAL_MEM flag. 1357 * For this to work properly the host controller code must first use the 1358 * function dma_declare_coherent_memory() to point out which memory area 1359 * that should be used for dma allocations. 1360 * 1361 * The HCD_LOCAL_MEM flag then tells the usb code to allocate all data for 1362 * dma using dma_alloc_coherent() which in turn allocates from the memory 1363 * area pointed out with dma_declare_coherent_memory(). 1364 * 1365 * So, to summarize... 1366 * 1367 * - We need "local" memory, canonical example being 1368 * a small SRAM on a discrete controller being the 1369 * only memory that the controller can read ... 1370 * (a) "normal" kernel memory is no good, and 1371 * (b) there's not enough to share 1372 * 1373 * - The only *portable* hook for such stuff in the 1374 * DMA framework is dma_declare_coherent_memory() 1375 * 1376 * - So we use that, even though the primary requirement 1377 * is that the memory be "local" (hence addressable 1378 * by that device), not "coherent". 1379 * 1380 */ 1381 1382 static int hcd_alloc_coherent(struct usb_bus *bus, 1383 gfp_t mem_flags, dma_addr_t *dma_handle, 1384 void **vaddr_handle, size_t size, 1385 enum dma_data_direction dir) 1386 { 1387 unsigned char *vaddr; 1388 1389 if (*vaddr_handle == NULL) { 1390 WARN_ON_ONCE(1); 1391 return -EFAULT; 1392 } 1393 1394 vaddr = hcd_buffer_alloc(bus, size + sizeof(vaddr), 1395 mem_flags, dma_handle); 1396 if (!vaddr) 1397 return -ENOMEM; 1398 1399 /* 1400 * Store the virtual address of the buffer at the end 1401 * of the allocated dma buffer. The size of the buffer 1402 * may be uneven so use unaligned functions instead 1403 * of just rounding up. It makes sense to optimize for 1404 * memory footprint over access speed since the amount 1405 * of memory available for dma may be limited. 1406 */ 1407 put_unaligned((unsigned long)*vaddr_handle, 1408 (unsigned long *)(vaddr + size)); 1409 1410 if (dir == DMA_TO_DEVICE) 1411 memcpy(vaddr, *vaddr_handle, size); 1412 1413 *vaddr_handle = vaddr; 1414 return 0; 1415 } 1416 1417 static void hcd_free_coherent(struct usb_bus *bus, dma_addr_t *dma_handle, 1418 void **vaddr_handle, size_t size, 1419 enum dma_data_direction dir) 1420 { 1421 unsigned char *vaddr = *vaddr_handle; 1422 1423 vaddr = (void *)get_unaligned((unsigned long *)(vaddr + size)); 1424 1425 if (dir == DMA_FROM_DEVICE) 1426 memcpy(vaddr, *vaddr_handle, size); 1427 1428 hcd_buffer_free(bus, size + sizeof(vaddr), *vaddr_handle, *dma_handle); 1429 1430 *vaddr_handle = vaddr; 1431 *dma_handle = 0; 1432 } 1433 1434 void usb_hcd_unmap_urb_setup_for_dma(struct usb_hcd *hcd, struct urb *urb) 1435 { 1436 if (IS_ENABLED(CONFIG_HAS_DMA) && 1437 (urb->transfer_flags & URB_SETUP_MAP_SINGLE)) 1438 dma_unmap_single(hcd->self.controller, 1439 urb->setup_dma, 1440 sizeof(struct usb_ctrlrequest), 1441 DMA_TO_DEVICE); 1442 else if (urb->transfer_flags & URB_SETUP_MAP_LOCAL) 1443 hcd_free_coherent(urb->dev->bus, 1444 &urb->setup_dma, 1445 (void **) &urb->setup_packet, 1446 sizeof(struct usb_ctrlrequest), 1447 DMA_TO_DEVICE); 1448 1449 /* Make it safe to call this routine more than once */ 1450 urb->transfer_flags &= ~(URB_SETUP_MAP_SINGLE | URB_SETUP_MAP_LOCAL); 1451 } 1452 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_setup_for_dma); 1453 1454 static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) 1455 { 1456 if (hcd->driver->unmap_urb_for_dma) 1457 hcd->driver->unmap_urb_for_dma(hcd, urb); 1458 else 1459 usb_hcd_unmap_urb_for_dma(hcd, urb); 1460 } 1461 1462 void usb_hcd_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) 1463 { 1464 enum dma_data_direction dir; 1465 1466 usb_hcd_unmap_urb_setup_for_dma(hcd, urb); 1467 1468 dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 1469 if (IS_ENABLED(CONFIG_HAS_DMA) && 1470 (urb->transfer_flags & URB_DMA_MAP_SG)) 1471 dma_unmap_sg(hcd->self.controller, 1472 urb->sg, 1473 urb->num_sgs, 1474 dir); 1475 else if (IS_ENABLED(CONFIG_HAS_DMA) && 1476 (urb->transfer_flags & URB_DMA_MAP_PAGE)) 1477 dma_unmap_page(hcd->self.controller, 1478 urb->transfer_dma, 1479 urb->transfer_buffer_length, 1480 dir); 1481 else if (IS_ENABLED(CONFIG_HAS_DMA) && 1482 (urb->transfer_flags & URB_DMA_MAP_SINGLE)) 1483 dma_unmap_single(hcd->self.controller, 1484 urb->transfer_dma, 1485 urb->transfer_buffer_length, 1486 dir); 1487 else if (urb->transfer_flags & URB_MAP_LOCAL) 1488 hcd_free_coherent(urb->dev->bus, 1489 &urb->transfer_dma, 1490 &urb->transfer_buffer, 1491 urb->transfer_buffer_length, 1492 dir); 1493 1494 /* Make it safe to call this routine more than once */ 1495 urb->transfer_flags &= ~(URB_DMA_MAP_SG | URB_DMA_MAP_PAGE | 1496 URB_DMA_MAP_SINGLE | URB_MAP_LOCAL); 1497 } 1498 EXPORT_SYMBOL_GPL(usb_hcd_unmap_urb_for_dma); 1499 1500 static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, 1501 gfp_t mem_flags) 1502 { 1503 if (hcd->driver->map_urb_for_dma) 1504 return hcd->driver->map_urb_for_dma(hcd, urb, mem_flags); 1505 else 1506 return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags); 1507 } 1508 1509 int usb_hcd_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, 1510 gfp_t mem_flags) 1511 { 1512 enum dma_data_direction dir; 1513 int ret = 0; 1514 1515 /* Map the URB's buffers for DMA access. 1516 * Lower level HCD code should use *_dma exclusively, 1517 * unless it uses pio or talks to another transport, 1518 * or uses the provided scatter gather list for bulk. 1519 */ 1520 1521 if (usb_endpoint_xfer_control(&urb->ep->desc)) { 1522 if (hcd->self.uses_pio_for_control) 1523 return ret; 1524 if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) { 1525 urb->setup_dma = dma_map_single( 1526 hcd->self.controller, 1527 urb->setup_packet, 1528 sizeof(struct usb_ctrlrequest), 1529 DMA_TO_DEVICE); 1530 if (dma_mapping_error(hcd->self.controller, 1531 urb->setup_dma)) 1532 return -EAGAIN; 1533 urb->transfer_flags |= URB_SETUP_MAP_SINGLE; 1534 } else if (hcd->driver->flags & HCD_LOCAL_MEM) { 1535 ret = hcd_alloc_coherent( 1536 urb->dev->bus, mem_flags, 1537 &urb->setup_dma, 1538 (void **)&urb->setup_packet, 1539 sizeof(struct usb_ctrlrequest), 1540 DMA_TO_DEVICE); 1541 if (ret) 1542 return ret; 1543 urb->transfer_flags |= URB_SETUP_MAP_LOCAL; 1544 } 1545 } 1546 1547 dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE; 1548 if (urb->transfer_buffer_length != 0 1549 && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) { 1550 if (IS_ENABLED(CONFIG_HAS_DMA) && hcd->self.uses_dma) { 1551 if (urb->num_sgs) { 1552 int n; 1553 1554 /* We don't support sg for isoc transfers ! */ 1555 if (usb_endpoint_xfer_isoc(&urb->ep->desc)) { 1556 WARN_ON(1); 1557 return -EINVAL; 1558 } 1559 1560 n = dma_map_sg( 1561 hcd->self.controller, 1562 urb->sg, 1563 urb->num_sgs, 1564 dir); 1565 if (n <= 0) 1566 ret = -EAGAIN; 1567 else 1568 urb->transfer_flags |= URB_DMA_MAP_SG; 1569 urb->num_mapped_sgs = n; 1570 if (n != urb->num_sgs) 1571 urb->transfer_flags |= 1572 URB_DMA_SG_COMBINED; 1573 } else if (urb->sg) { 1574 struct scatterlist *sg = urb->sg; 1575 urb->transfer_dma = dma_map_page( 1576 hcd->self.controller, 1577 sg_page(sg), 1578 sg->offset, 1579 urb->transfer_buffer_length, 1580 dir); 1581 if (dma_mapping_error(hcd->self.controller, 1582 urb->transfer_dma)) 1583 ret = -EAGAIN; 1584 else 1585 urb->transfer_flags |= URB_DMA_MAP_PAGE; 1586 } else if (is_vmalloc_addr(urb->transfer_buffer)) { 1587 WARN_ONCE(1, "transfer buffer not dma capable\n"); 1588 ret = -EAGAIN; 1589 } else { 1590 urb->transfer_dma = dma_map_single( 1591 hcd->self.controller, 1592 urb->transfer_buffer, 1593 urb->transfer_buffer_length, 1594 dir); 1595 if (dma_mapping_error(hcd->self.controller, 1596 urb->transfer_dma)) 1597 ret = -EAGAIN; 1598 else 1599 urb->transfer_flags |= URB_DMA_MAP_SINGLE; 1600 } 1601 } else if (hcd->driver->flags & HCD_LOCAL_MEM) { 1602 ret = hcd_alloc_coherent( 1603 urb->dev->bus, mem_flags, 1604 &urb->transfer_dma, 1605 &urb->transfer_buffer, 1606 urb->transfer_buffer_length, 1607 dir); 1608 if (ret == 0) 1609 urb->transfer_flags |= URB_MAP_LOCAL; 1610 } 1611 if (ret && (urb->transfer_flags & (URB_SETUP_MAP_SINGLE | 1612 URB_SETUP_MAP_LOCAL))) 1613 usb_hcd_unmap_urb_for_dma(hcd, urb); 1614 } 1615 return ret; 1616 } 1617 EXPORT_SYMBOL_GPL(usb_hcd_map_urb_for_dma); 1618 1619 /*-------------------------------------------------------------------------*/ 1620 1621 /* may be called in any context with a valid urb->dev usecount 1622 * caller surrenders "ownership" of urb 1623 * expects usb_submit_urb() to have sanity checked and conditioned all 1624 * inputs in the urb 1625 */ 1626 int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags) 1627 { 1628 int status; 1629 struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); 1630 1631 /* increment urb's reference count as part of giving it to the HCD 1632 * (which will control it). HCD guarantees that it either returns 1633 * an error or calls giveback(), but not both. 1634 */ 1635 usb_get_urb(urb); 1636 atomic_inc(&urb->use_count); 1637 atomic_inc(&urb->dev->urbnum); 1638 usbmon_urb_submit(&hcd->self, urb); 1639 1640 /* NOTE requirements on root-hub callers (usbfs and the hub 1641 * driver, for now): URBs' urb->transfer_buffer must be 1642 * valid and usb_buffer_{sync,unmap}() not be needed, since 1643 * they could clobber root hub response data. Also, control 1644 * URBs must be submitted in process context with interrupts 1645 * enabled. 1646 */ 1647 1648 if (is_root_hub(urb->dev)) { 1649 status = rh_urb_enqueue(hcd, urb); 1650 } else { 1651 status = map_urb_for_dma(hcd, urb, mem_flags); 1652 if (likely(status == 0)) { 1653 status = hcd->driver->urb_enqueue(hcd, urb, mem_flags); 1654 if (unlikely(status)) 1655 unmap_urb_for_dma(hcd, urb); 1656 } 1657 } 1658 1659 if (unlikely(status)) { 1660 usbmon_urb_submit_error(&hcd->self, urb, status); 1661 urb->hcpriv = NULL; 1662 INIT_LIST_HEAD(&urb->urb_list); 1663 atomic_dec(&urb->use_count); 1664 atomic_dec(&urb->dev->urbnum); 1665 if (atomic_read(&urb->reject)) 1666 wake_up(&usb_kill_urb_queue); 1667 usb_put_urb(urb); 1668 } 1669 return status; 1670 } 1671 1672 /*-------------------------------------------------------------------------*/ 1673 1674 /* this makes the hcd giveback() the urb more quickly, by kicking it 1675 * off hardware queues (which may take a while) and returning it as 1676 * soon as practical. we've already set up the urb's return status, 1677 * but we can't know if the callback completed already. 1678 */ 1679 static int unlink1(struct usb_hcd *hcd, struct urb *urb, int status) 1680 { 1681 int value; 1682 1683 if (is_root_hub(urb->dev)) 1684 value = usb_rh_urb_dequeue(hcd, urb, status); 1685 else { 1686 1687 /* The only reason an HCD might fail this call is if 1688 * it has not yet fully queued the urb to begin with. 1689 * Such failures should be harmless. */ 1690 value = hcd->driver->urb_dequeue(hcd, urb, status); 1691 } 1692 return value; 1693 } 1694 1695 /* 1696 * called in any context 1697 * 1698 * caller guarantees urb won't be recycled till both unlink() 1699 * and the urb's completion function return 1700 */ 1701 int usb_hcd_unlink_urb (struct urb *urb, int status) 1702 { 1703 struct usb_hcd *hcd; 1704 struct usb_device *udev = urb->dev; 1705 int retval = -EIDRM; 1706 unsigned long flags; 1707 1708 /* Prevent the device and bus from going away while 1709 * the unlink is carried out. If they are already gone 1710 * then urb->use_count must be 0, since disconnected 1711 * devices can't have any active URBs. 1712 */ 1713 spin_lock_irqsave(&hcd_urb_unlink_lock, flags); 1714 if (atomic_read(&urb->use_count) > 0) { 1715 retval = 0; 1716 usb_get_dev(udev); 1717 } 1718 spin_unlock_irqrestore(&hcd_urb_unlink_lock, flags); 1719 if (retval == 0) { 1720 hcd = bus_to_hcd(urb->dev->bus); 1721 retval = unlink1(hcd, urb, status); 1722 if (retval == 0) 1723 retval = -EINPROGRESS; 1724 else if (retval != -EIDRM && retval != -EBUSY) 1725 dev_dbg(&udev->dev, "hcd_unlink_urb %p fail %d\n", 1726 urb, retval); 1727 usb_put_dev(udev); 1728 } 1729 return retval; 1730 } 1731 1732 /*-------------------------------------------------------------------------*/ 1733 1734 static void __usb_hcd_giveback_urb(struct urb *urb) 1735 { 1736 struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); 1737 struct usb_anchor *anchor = urb->anchor; 1738 int status = urb->unlinked; 1739 unsigned long flags; 1740 1741 urb->hcpriv = NULL; 1742 if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) && 1743 urb->actual_length < urb->transfer_buffer_length && 1744 !status)) 1745 status = -EREMOTEIO; 1746 1747 unmap_urb_for_dma(hcd, urb); 1748 usbmon_urb_complete(&hcd->self, urb, status); 1749 usb_anchor_suspend_wakeups(anchor); 1750 usb_unanchor_urb(urb); 1751 if (likely(status == 0)) 1752 usb_led_activity(USB_LED_EVENT_HOST); 1753 1754 /* pass ownership to the completion handler */ 1755 urb->status = status; 1756 1757 /* 1758 * We disable local IRQs here avoid possible deadlock because 1759 * drivers may call spin_lock() to hold lock which might be 1760 * acquired in one hard interrupt handler. 1761 * 1762 * The local_irq_save()/local_irq_restore() around complete() 1763 * will be removed if current USB drivers have been cleaned up 1764 * and no one may trigger the above deadlock situation when 1765 * running complete() in tasklet. 1766 */ 1767 local_irq_save(flags); 1768 urb->complete(urb); 1769 local_irq_restore(flags); 1770 1771 usb_anchor_resume_wakeups(anchor); 1772 atomic_dec(&urb->use_count); 1773 if (unlikely(atomic_read(&urb->reject))) 1774 wake_up(&usb_kill_urb_queue); 1775 usb_put_urb(urb); 1776 } 1777 1778 static void usb_giveback_urb_bh(unsigned long param) 1779 { 1780 struct giveback_urb_bh *bh = (struct giveback_urb_bh *)param; 1781 struct list_head local_list; 1782 1783 spin_lock_irq(&bh->lock); 1784 bh->running = true; 1785 restart: 1786 list_replace_init(&bh->head, &local_list); 1787 spin_unlock_irq(&bh->lock); 1788 1789 while (!list_empty(&local_list)) { 1790 struct urb *urb; 1791 1792 urb = list_entry(local_list.next, struct urb, urb_list); 1793 list_del_init(&urb->urb_list); 1794 bh->completing_ep = urb->ep; 1795 __usb_hcd_giveback_urb(urb); 1796 bh->completing_ep = NULL; 1797 } 1798 1799 /* check if there are new URBs to giveback */ 1800 spin_lock_irq(&bh->lock); 1801 if (!list_empty(&bh->head)) 1802 goto restart; 1803 bh->running = false; 1804 spin_unlock_irq(&bh->lock); 1805 } 1806 1807 /** 1808 * usb_hcd_giveback_urb - return URB from HCD to device driver 1809 * @hcd: host controller returning the URB 1810 * @urb: urb being returned to the USB device driver. 1811 * @status: completion status code for the URB. 1812 * Context: in_interrupt() 1813 * 1814 * This hands the URB from HCD to its USB device driver, using its 1815 * completion function. The HCD has freed all per-urb resources 1816 * (and is done using urb->hcpriv). It also released all HCD locks; 1817 * the device driver won't cause problems if it frees, modifies, 1818 * or resubmits this URB. 1819 * 1820 * If @urb was unlinked, the value of @status will be overridden by 1821 * @urb->unlinked. Erroneous short transfers are detected in case 1822 * the HCD hasn't checked for them. 1823 */ 1824 void usb_hcd_giveback_urb(struct usb_hcd *hcd, struct urb *urb, int status) 1825 { 1826 struct giveback_urb_bh *bh; 1827 bool running, high_prio_bh; 1828 1829 /* pass status to tasklet via unlinked */ 1830 if (likely(!urb->unlinked)) 1831 urb->unlinked = status; 1832 1833 if (!hcd_giveback_urb_in_bh(hcd) && !is_root_hub(urb->dev)) { 1834 __usb_hcd_giveback_urb(urb); 1835 return; 1836 } 1837 1838 if (usb_pipeisoc(urb->pipe) || usb_pipeint(urb->pipe)) { 1839 bh = &hcd->high_prio_bh; 1840 high_prio_bh = true; 1841 } else { 1842 bh = &hcd->low_prio_bh; 1843 high_prio_bh = false; 1844 } 1845 1846 spin_lock(&bh->lock); 1847 list_add_tail(&urb->urb_list, &bh->head); 1848 running = bh->running; 1849 spin_unlock(&bh->lock); 1850 1851 if (running) 1852 ; 1853 else if (high_prio_bh) 1854 tasklet_hi_schedule(&bh->bh); 1855 else 1856 tasklet_schedule(&bh->bh); 1857 } 1858 EXPORT_SYMBOL_GPL(usb_hcd_giveback_urb); 1859 1860 /*-------------------------------------------------------------------------*/ 1861 1862 /* Cancel all URBs pending on this endpoint and wait for the endpoint's 1863 * queue to drain completely. The caller must first insure that no more 1864 * URBs can be submitted for this endpoint. 1865 */ 1866 void usb_hcd_flush_endpoint(struct usb_device *udev, 1867 struct usb_host_endpoint *ep) 1868 { 1869 struct usb_hcd *hcd; 1870 struct urb *urb; 1871 1872 if (!ep) 1873 return; 1874 might_sleep(); 1875 hcd = bus_to_hcd(udev->bus); 1876 1877 /* No more submits can occur */ 1878 spin_lock_irq(&hcd_urb_list_lock); 1879 rescan: 1880 list_for_each_entry (urb, &ep->urb_list, urb_list) { 1881 int is_in; 1882 1883 if (urb->unlinked) 1884 continue; 1885 usb_get_urb (urb); 1886 is_in = usb_urb_dir_in(urb); 1887 spin_unlock(&hcd_urb_list_lock); 1888 1889 /* kick hcd */ 1890 unlink1(hcd, urb, -ESHUTDOWN); 1891 dev_dbg (hcd->self.controller, 1892 "shutdown urb %p ep%d%s%s\n", 1893 urb, usb_endpoint_num(&ep->desc), 1894 is_in ? "in" : "out", 1895 ({ char *s; 1896 1897 switch (usb_endpoint_type(&ep->desc)) { 1898 case USB_ENDPOINT_XFER_CONTROL: 1899 s = ""; break; 1900 case USB_ENDPOINT_XFER_BULK: 1901 s = "-bulk"; break; 1902 case USB_ENDPOINT_XFER_INT: 1903 s = "-intr"; break; 1904 default: 1905 s = "-iso"; break; 1906 }; 1907 s; 1908 })); 1909 usb_put_urb (urb); 1910 1911 /* list contents may have changed */ 1912 spin_lock(&hcd_urb_list_lock); 1913 goto rescan; 1914 } 1915 spin_unlock_irq(&hcd_urb_list_lock); 1916 1917 /* Wait until the endpoint queue is completely empty */ 1918 while (!list_empty (&ep->urb_list)) { 1919 spin_lock_irq(&hcd_urb_list_lock); 1920 1921 /* The list may have changed while we acquired the spinlock */ 1922 urb = NULL; 1923 if (!list_empty (&ep->urb_list)) { 1924 urb = list_entry (ep->urb_list.prev, struct urb, 1925 urb_list); 1926 usb_get_urb (urb); 1927 } 1928 spin_unlock_irq(&hcd_urb_list_lock); 1929 1930 if (urb) { 1931 usb_kill_urb (urb); 1932 usb_put_urb (urb); 1933 } 1934 } 1935 } 1936 1937 /** 1938 * usb_hcd_alloc_bandwidth - check whether a new bandwidth setting exceeds 1939 * the bus bandwidth 1940 * @udev: target &usb_device 1941 * @new_config: new configuration to install 1942 * @cur_alt: the current alternate interface setting 1943 * @new_alt: alternate interface setting that is being installed 1944 * 1945 * To change configurations, pass in the new configuration in new_config, 1946 * and pass NULL for cur_alt and new_alt. 1947 * 1948 * To reset a device's configuration (put the device in the ADDRESSED state), 1949 * pass in NULL for new_config, cur_alt, and new_alt. 1950 * 1951 * To change alternate interface settings, pass in NULL for new_config, 1952 * pass in the current alternate interface setting in cur_alt, 1953 * and pass in the new alternate interface setting in new_alt. 1954 * 1955 * Return: An error if the requested bandwidth change exceeds the 1956 * bus bandwidth or host controller internal resources. 1957 */ 1958 int usb_hcd_alloc_bandwidth(struct usb_device *udev, 1959 struct usb_host_config *new_config, 1960 struct usb_host_interface *cur_alt, 1961 struct usb_host_interface *new_alt) 1962 { 1963 int num_intfs, i, j; 1964 struct usb_host_interface *alt = NULL; 1965 int ret = 0; 1966 struct usb_hcd *hcd; 1967 struct usb_host_endpoint *ep; 1968 1969 hcd = bus_to_hcd(udev->bus); 1970 if (!hcd->driver->check_bandwidth) 1971 return 0; 1972 1973 /* Configuration is being removed - set configuration 0 */ 1974 if (!new_config && !cur_alt) { 1975 for (i = 1; i < 16; ++i) { 1976 ep = udev->ep_out[i]; 1977 if (ep) 1978 hcd->driver->drop_endpoint(hcd, udev, ep); 1979 ep = udev->ep_in[i]; 1980 if (ep) 1981 hcd->driver->drop_endpoint(hcd, udev, ep); 1982 } 1983 hcd->driver->check_bandwidth(hcd, udev); 1984 return 0; 1985 } 1986 /* Check if the HCD says there's enough bandwidth. Enable all endpoints 1987 * each interface's alt setting 0 and ask the HCD to check the bandwidth 1988 * of the bus. There will always be bandwidth for endpoint 0, so it's 1989 * ok to exclude it. 1990 */ 1991 if (new_config) { 1992 num_intfs = new_config->desc.bNumInterfaces; 1993 /* Remove endpoints (except endpoint 0, which is always on the 1994 * schedule) from the old config from the schedule 1995 */ 1996 for (i = 1; i < 16; ++i) { 1997 ep = udev->ep_out[i]; 1998 if (ep) { 1999 ret = hcd->driver->drop_endpoint(hcd, udev, ep); 2000 if (ret < 0) 2001 goto reset; 2002 } 2003 ep = udev->ep_in[i]; 2004 if (ep) { 2005 ret = hcd->driver->drop_endpoint(hcd, udev, ep); 2006 if (ret < 0) 2007 goto reset; 2008 } 2009 } 2010 for (i = 0; i < num_intfs; ++i) { 2011 struct usb_host_interface *first_alt; 2012 int iface_num; 2013 2014 first_alt = &new_config->intf_cache[i]->altsetting[0]; 2015 iface_num = first_alt->desc.bInterfaceNumber; 2016 /* Set up endpoints for alternate interface setting 0 */ 2017 alt = usb_find_alt_setting(new_config, iface_num, 0); 2018 if (!alt) 2019 /* No alt setting 0? Pick the first setting. */ 2020 alt = first_alt; 2021 2022 for (j = 0; j < alt->desc.bNumEndpoints; j++) { 2023 ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]); 2024 if (ret < 0) 2025 goto reset; 2026 } 2027 } 2028 } 2029 if (cur_alt && new_alt) { 2030 struct usb_interface *iface = usb_ifnum_to_if(udev, 2031 cur_alt->desc.bInterfaceNumber); 2032 2033 if (!iface) 2034 return -EINVAL; 2035 if (iface->resetting_device) { 2036 /* 2037 * The USB core just reset the device, so the xHCI host 2038 * and the device will think alt setting 0 is installed. 2039 * However, the USB core will pass in the alternate 2040 * setting installed before the reset as cur_alt. Dig 2041 * out the alternate setting 0 structure, or the first 2042 * alternate setting if a broken device doesn't have alt 2043 * setting 0. 2044 */ 2045 cur_alt = usb_altnum_to_altsetting(iface, 0); 2046 if (!cur_alt) 2047 cur_alt = &iface->altsetting[0]; 2048 } 2049 2050 /* Drop all the endpoints in the current alt setting */ 2051 for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) { 2052 ret = hcd->driver->drop_endpoint(hcd, udev, 2053 &cur_alt->endpoint[i]); 2054 if (ret < 0) 2055 goto reset; 2056 } 2057 /* Add all the endpoints in the new alt setting */ 2058 for (i = 0; i < new_alt->desc.bNumEndpoints; i++) { 2059 ret = hcd->driver->add_endpoint(hcd, udev, 2060 &new_alt->endpoint[i]); 2061 if (ret < 0) 2062 goto reset; 2063 } 2064 } 2065 ret = hcd->driver->check_bandwidth(hcd, udev); 2066 reset: 2067 if (ret < 0) 2068 hcd->driver->reset_bandwidth(hcd, udev); 2069 return ret; 2070 } 2071 2072 /* Disables the endpoint: synchronizes with the hcd to make sure all 2073 * endpoint state is gone from hardware. usb_hcd_flush_endpoint() must 2074 * have been called previously. Use for set_configuration, set_interface, 2075 * driver removal, physical disconnect. 2076 * 2077 * example: a qh stored in ep->hcpriv, holding state related to endpoint 2078 * type, maxpacket size, toggle, halt status, and scheduling. 2079 */ 2080 void usb_hcd_disable_endpoint(struct usb_device *udev, 2081 struct usb_host_endpoint *ep) 2082 { 2083 struct usb_hcd *hcd; 2084 2085 might_sleep(); 2086 hcd = bus_to_hcd(udev->bus); 2087 if (hcd->driver->endpoint_disable) 2088 hcd->driver->endpoint_disable(hcd, ep); 2089 } 2090 2091 /** 2092 * usb_hcd_reset_endpoint - reset host endpoint state 2093 * @udev: USB device. 2094 * @ep: the endpoint to reset. 2095 * 2096 * Resets any host endpoint state such as the toggle bit, sequence 2097 * number and current window. 2098 */ 2099 void usb_hcd_reset_endpoint(struct usb_device *udev, 2100 struct usb_host_endpoint *ep) 2101 { 2102 struct usb_hcd *hcd = bus_to_hcd(udev->bus); 2103 2104 if (hcd->driver->endpoint_reset) 2105 hcd->driver->endpoint_reset(hcd, ep); 2106 else { 2107 int epnum = usb_endpoint_num(&ep->desc); 2108 int is_out = usb_endpoint_dir_out(&ep->desc); 2109 int is_control = usb_endpoint_xfer_control(&ep->desc); 2110 2111 usb_settoggle(udev, epnum, is_out, 0); 2112 if (is_control) 2113 usb_settoggle(udev, epnum, !is_out, 0); 2114 } 2115 } 2116 2117 /** 2118 * usb_alloc_streams - allocate bulk endpoint stream IDs. 2119 * @interface: alternate setting that includes all endpoints. 2120 * @eps: array of endpoints that need streams. 2121 * @num_eps: number of endpoints in the array. 2122 * @num_streams: number of streams to allocate. 2123 * @mem_flags: flags hcd should use to allocate memory. 2124 * 2125 * Sets up a group of bulk endpoints to have @num_streams stream IDs available. 2126 * Drivers may queue multiple transfers to different stream IDs, which may 2127 * complete in a different order than they were queued. 2128 * 2129 * Return: On success, the number of allocated streams. On failure, a negative 2130 * error code. 2131 */ 2132 int usb_alloc_streams(struct usb_interface *interface, 2133 struct usb_host_endpoint **eps, unsigned int num_eps, 2134 unsigned int num_streams, gfp_t mem_flags) 2135 { 2136 struct usb_hcd *hcd; 2137 struct usb_device *dev; 2138 int i, ret; 2139 2140 dev = interface_to_usbdev(interface); 2141 hcd = bus_to_hcd(dev->bus); 2142 if (!hcd->driver->alloc_streams || !hcd->driver->free_streams) 2143 return -EINVAL; 2144 if (dev->speed < USB_SPEED_SUPER) 2145 return -EINVAL; 2146 if (dev->state < USB_STATE_CONFIGURED) 2147 return -ENODEV; 2148 2149 for (i = 0; i < num_eps; i++) { 2150 /* Streams only apply to bulk endpoints. */ 2151 if (!usb_endpoint_xfer_bulk(&eps[i]->desc)) 2152 return -EINVAL; 2153 /* Re-alloc is not allowed */ 2154 if (eps[i]->streams) 2155 return -EINVAL; 2156 } 2157 2158 ret = hcd->driver->alloc_streams(hcd, dev, eps, num_eps, 2159 num_streams, mem_flags); 2160 if (ret < 0) 2161 return ret; 2162 2163 for (i = 0; i < num_eps; i++) 2164 eps[i]->streams = ret; 2165 2166 return ret; 2167 } 2168 EXPORT_SYMBOL_GPL(usb_alloc_streams); 2169 2170 /** 2171 * usb_free_streams - free bulk endpoint stream IDs. 2172 * @interface: alternate setting that includes all endpoints. 2173 * @eps: array of endpoints to remove streams from. 2174 * @num_eps: number of endpoints in the array. 2175 * @mem_flags: flags hcd should use to allocate memory. 2176 * 2177 * Reverts a group of bulk endpoints back to not using stream IDs. 2178 * Can fail if we are given bad arguments, or HCD is broken. 2179 * 2180 * Return: 0 on success. On failure, a negative error code. 2181 */ 2182 int usb_free_streams(struct usb_interface *interface, 2183 struct usb_host_endpoint **eps, unsigned int num_eps, 2184 gfp_t mem_flags) 2185 { 2186 struct usb_hcd *hcd; 2187 struct usb_device *dev; 2188 int i, ret; 2189 2190 dev = interface_to_usbdev(interface); 2191 hcd = bus_to_hcd(dev->bus); 2192 if (dev->speed < USB_SPEED_SUPER) 2193 return -EINVAL; 2194 2195 /* Double-free is not allowed */ 2196 for (i = 0; i < num_eps; i++) 2197 if (!eps[i] || !eps[i]->streams) 2198 return -EINVAL; 2199 2200 ret = hcd->driver->free_streams(hcd, dev, eps, num_eps, mem_flags); 2201 if (ret < 0) 2202 return ret; 2203 2204 for (i = 0; i < num_eps; i++) 2205 eps[i]->streams = 0; 2206 2207 return ret; 2208 } 2209 EXPORT_SYMBOL_GPL(usb_free_streams); 2210 2211 /* Protect against drivers that try to unlink URBs after the device 2212 * is gone, by waiting until all unlinks for @udev are finished. 2213 * Since we don't currently track URBs by device, simply wait until 2214 * nothing is running in the locked region of usb_hcd_unlink_urb(). 2215 */ 2216 void usb_hcd_synchronize_unlinks(struct usb_device *udev) 2217 { 2218 spin_lock_irq(&hcd_urb_unlink_lock); 2219 spin_unlock_irq(&hcd_urb_unlink_lock); 2220 } 2221 2222 /*-------------------------------------------------------------------------*/ 2223 2224 /* called in any context */ 2225 int usb_hcd_get_frame_number (struct usb_device *udev) 2226 { 2227 struct usb_hcd *hcd = bus_to_hcd(udev->bus); 2228 2229 if (!HCD_RH_RUNNING(hcd)) 2230 return -ESHUTDOWN; 2231 return hcd->driver->get_frame_number (hcd); 2232 } 2233 2234 /*-------------------------------------------------------------------------*/ 2235 2236 #ifdef CONFIG_PM 2237 2238 int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg) 2239 { 2240 struct usb_hcd *hcd = bus_to_hcd(rhdev->bus); 2241 int status; 2242 int old_state = hcd->state; 2243 2244 dev_dbg(&rhdev->dev, "bus %ssuspend, wakeup %d\n", 2245 (PMSG_IS_AUTO(msg) ? "auto-" : ""), 2246 rhdev->do_remote_wakeup); 2247 if (HCD_DEAD(hcd)) { 2248 dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "suspend"); 2249 return 0; 2250 } 2251 2252 if (!hcd->driver->bus_suspend) { 2253 status = -ENOENT; 2254 } else { 2255 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2256 hcd->state = HC_STATE_QUIESCING; 2257 status = hcd->driver->bus_suspend(hcd); 2258 } 2259 if (status == 0) { 2260 usb_set_device_state(rhdev, USB_STATE_SUSPENDED); 2261 hcd->state = HC_STATE_SUSPENDED; 2262 2263 /* Did we race with a root-hub wakeup event? */ 2264 if (rhdev->do_remote_wakeup) { 2265 char buffer[6]; 2266 2267 status = hcd->driver->hub_status_data(hcd, buffer); 2268 if (status != 0) { 2269 dev_dbg(&rhdev->dev, "suspend raced with wakeup event\n"); 2270 hcd_bus_resume(rhdev, PMSG_AUTO_RESUME); 2271 status = -EBUSY; 2272 } 2273 } 2274 } else { 2275 spin_lock_irq(&hcd_root_hub_lock); 2276 if (!HCD_DEAD(hcd)) { 2277 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2278 hcd->state = old_state; 2279 } 2280 spin_unlock_irq(&hcd_root_hub_lock); 2281 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", 2282 "suspend", status); 2283 } 2284 return status; 2285 } 2286 2287 int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) 2288 { 2289 struct usb_hcd *hcd = bus_to_hcd(rhdev->bus); 2290 int status; 2291 int old_state = hcd->state; 2292 2293 dev_dbg(&rhdev->dev, "usb %sresume\n", 2294 (PMSG_IS_AUTO(msg) ? "auto-" : "")); 2295 if (HCD_DEAD(hcd)) { 2296 dev_dbg(&rhdev->dev, "skipped %s of dead bus\n", "resume"); 2297 return 0; 2298 } 2299 if (!hcd->driver->bus_resume) 2300 return -ENOENT; 2301 if (HCD_RH_RUNNING(hcd)) 2302 return 0; 2303 2304 hcd->state = HC_STATE_RESUMING; 2305 status = hcd->driver->bus_resume(hcd); 2306 clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); 2307 if (status == 0) { 2308 struct usb_device *udev; 2309 int port1; 2310 2311 spin_lock_irq(&hcd_root_hub_lock); 2312 if (!HCD_DEAD(hcd)) { 2313 usb_set_device_state(rhdev, rhdev->actconfig 2314 ? USB_STATE_CONFIGURED 2315 : USB_STATE_ADDRESS); 2316 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2317 hcd->state = HC_STATE_RUNNING; 2318 } 2319 spin_unlock_irq(&hcd_root_hub_lock); 2320 2321 /* 2322 * Check whether any of the enabled ports on the root hub are 2323 * unsuspended. If they are then a TRSMRCY delay is needed 2324 * (this is what the USB-2 spec calls a "global resume"). 2325 * Otherwise we can skip the delay. 2326 */ 2327 usb_hub_for_each_child(rhdev, port1, udev) { 2328 if (udev->state != USB_STATE_NOTATTACHED && 2329 !udev->port_is_suspended) { 2330 usleep_range(10000, 11000); /* TRSMRCY */ 2331 break; 2332 } 2333 } 2334 } else { 2335 hcd->state = old_state; 2336 dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", 2337 "resume", status); 2338 if (status != -ESHUTDOWN) 2339 usb_hc_died(hcd); 2340 } 2341 return status; 2342 } 2343 2344 /* Workqueue routine for root-hub remote wakeup */ 2345 static void hcd_resume_work(struct work_struct *work) 2346 { 2347 struct usb_hcd *hcd = container_of(work, struct usb_hcd, wakeup_work); 2348 struct usb_device *udev = hcd->self.root_hub; 2349 2350 usb_remote_wakeup(udev); 2351 } 2352 2353 /** 2354 * usb_hcd_resume_root_hub - called by HCD to resume its root hub 2355 * @hcd: host controller for this root hub 2356 * 2357 * The USB host controller calls this function when its root hub is 2358 * suspended (with the remote wakeup feature enabled) and a remote 2359 * wakeup request is received. The routine submits a workqueue request 2360 * to resume the root hub (that is, manage its downstream ports again). 2361 */ 2362 void usb_hcd_resume_root_hub (struct usb_hcd *hcd) 2363 { 2364 unsigned long flags; 2365 2366 spin_lock_irqsave (&hcd_root_hub_lock, flags); 2367 if (hcd->rh_registered) { 2368 set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags); 2369 queue_work(pm_wq, &hcd->wakeup_work); 2370 } 2371 spin_unlock_irqrestore (&hcd_root_hub_lock, flags); 2372 } 2373 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub); 2374 2375 #endif /* CONFIG_PM */ 2376 2377 /*-------------------------------------------------------------------------*/ 2378 2379 #ifdef CONFIG_USB_OTG 2380 2381 /** 2382 * usb_bus_start_enum - start immediate enumeration (for OTG) 2383 * @bus: the bus (must use hcd framework) 2384 * @port_num: 1-based number of port; usually bus->otg_port 2385 * Context: in_interrupt() 2386 * 2387 * Starts enumeration, with an immediate reset followed later by 2388 * hub_wq identifying and possibly configuring the device. 2389 * This is needed by OTG controller drivers, where it helps meet 2390 * HNP protocol timing requirements for starting a port reset. 2391 * 2392 * Return: 0 if successful. 2393 */ 2394 int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num) 2395 { 2396 struct usb_hcd *hcd; 2397 int status = -EOPNOTSUPP; 2398 2399 /* NOTE: since HNP can't start by grabbing the bus's address0_sem, 2400 * boards with root hubs hooked up to internal devices (instead of 2401 * just the OTG port) may need more attention to resetting... 2402 */ 2403 hcd = bus_to_hcd(bus); 2404 if (port_num && hcd->driver->start_port_reset) 2405 status = hcd->driver->start_port_reset(hcd, port_num); 2406 2407 /* allocate hub_wq shortly after (first) root port reset finishes; 2408 * it may issue others, until at least 50 msecs have passed. 2409 */ 2410 if (status == 0) 2411 mod_timer(&hcd->rh_timer, jiffies + msecs_to_jiffies(10)); 2412 return status; 2413 } 2414 EXPORT_SYMBOL_GPL(usb_bus_start_enum); 2415 2416 #endif 2417 2418 /*-------------------------------------------------------------------------*/ 2419 2420 /** 2421 * usb_hcd_irq - hook IRQs to HCD framework (bus glue) 2422 * @irq: the IRQ being raised 2423 * @__hcd: pointer to the HCD whose IRQ is being signaled 2424 * 2425 * If the controller isn't HALTed, calls the driver's irq handler. 2426 * Checks whether the controller is now dead. 2427 * 2428 * Return: %IRQ_HANDLED if the IRQ was handled. %IRQ_NONE otherwise. 2429 */ 2430 irqreturn_t usb_hcd_irq (int irq, void *__hcd) 2431 { 2432 struct usb_hcd *hcd = __hcd; 2433 irqreturn_t rc; 2434 2435 if (unlikely(HCD_DEAD(hcd) || !HCD_HW_ACCESSIBLE(hcd))) 2436 rc = IRQ_NONE; 2437 else if (hcd->driver->irq(hcd) == IRQ_NONE) 2438 rc = IRQ_NONE; 2439 else 2440 rc = IRQ_HANDLED; 2441 2442 return rc; 2443 } 2444 EXPORT_SYMBOL_GPL(usb_hcd_irq); 2445 2446 /*-------------------------------------------------------------------------*/ 2447 2448 /** 2449 * usb_hc_died - report abnormal shutdown of a host controller (bus glue) 2450 * @hcd: pointer to the HCD representing the controller 2451 * 2452 * This is called by bus glue to report a USB host controller that died 2453 * while operations may still have been pending. It's called automatically 2454 * by the PCI glue, so only glue for non-PCI busses should need to call it. 2455 * 2456 * Only call this function with the primary HCD. 2457 */ 2458 void usb_hc_died (struct usb_hcd *hcd) 2459 { 2460 unsigned long flags; 2461 2462 dev_err (hcd->self.controller, "HC died; cleaning up\n"); 2463 2464 spin_lock_irqsave (&hcd_root_hub_lock, flags); 2465 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2466 set_bit(HCD_FLAG_DEAD, &hcd->flags); 2467 if (hcd->rh_registered) { 2468 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2469 2470 /* make hub_wq clean up old urbs and devices */ 2471 usb_set_device_state (hcd->self.root_hub, 2472 USB_STATE_NOTATTACHED); 2473 usb_kick_hub_wq(hcd->self.root_hub); 2474 } 2475 if (usb_hcd_is_primary_hcd(hcd) && hcd->shared_hcd) { 2476 hcd = hcd->shared_hcd; 2477 if (hcd->rh_registered) { 2478 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2479 2480 /* make hub_wq clean up old urbs and devices */ 2481 usb_set_device_state(hcd->self.root_hub, 2482 USB_STATE_NOTATTACHED); 2483 usb_kick_hub_wq(hcd->self.root_hub); 2484 } 2485 } 2486 spin_unlock_irqrestore (&hcd_root_hub_lock, flags); 2487 /* Make sure that the other roothub is also deallocated. */ 2488 } 2489 EXPORT_SYMBOL_GPL (usb_hc_died); 2490 2491 /*-------------------------------------------------------------------------*/ 2492 2493 static void init_giveback_urb_bh(struct giveback_urb_bh *bh) 2494 { 2495 2496 spin_lock_init(&bh->lock); 2497 INIT_LIST_HEAD(&bh->head); 2498 tasklet_init(&bh->bh, usb_giveback_urb_bh, (unsigned long)bh); 2499 } 2500 2501 /** 2502 * usb_create_shared_hcd - create and initialize an HCD structure 2503 * @driver: HC driver that will use this hcd 2504 * @dev: device for this HC, stored in hcd->self.controller 2505 * @bus_name: value to store in hcd->self.bus_name 2506 * @primary_hcd: a pointer to the usb_hcd structure that is sharing the 2507 * PCI device. Only allocate certain resources for the primary HCD 2508 * Context: !in_interrupt() 2509 * 2510 * Allocate a struct usb_hcd, with extra space at the end for the 2511 * HC driver's private data. Initialize the generic members of the 2512 * hcd structure. 2513 * 2514 * Return: On success, a pointer to the created and initialized HCD structure. 2515 * On failure (e.g. if memory is unavailable), %NULL. 2516 */ 2517 struct usb_hcd *usb_create_shared_hcd(const struct hc_driver *driver, 2518 struct device *dev, const char *bus_name, 2519 struct usb_hcd *primary_hcd) 2520 { 2521 struct usb_hcd *hcd; 2522 2523 hcd = kzalloc(sizeof(*hcd) + driver->hcd_priv_size, GFP_KERNEL); 2524 if (!hcd) 2525 return NULL; 2526 if (primary_hcd == NULL) { 2527 hcd->address0_mutex = kmalloc(sizeof(*hcd->address0_mutex), 2528 GFP_KERNEL); 2529 if (!hcd->address0_mutex) { 2530 kfree(hcd); 2531 dev_dbg(dev, "hcd address0 mutex alloc failed\n"); 2532 return NULL; 2533 } 2534 mutex_init(hcd->address0_mutex); 2535 hcd->bandwidth_mutex = kmalloc(sizeof(*hcd->bandwidth_mutex), 2536 GFP_KERNEL); 2537 if (!hcd->bandwidth_mutex) { 2538 kfree(hcd); 2539 dev_dbg(dev, "hcd bandwidth mutex alloc failed\n"); 2540 return NULL; 2541 } 2542 mutex_init(hcd->bandwidth_mutex); 2543 dev_set_drvdata(dev, hcd); 2544 } else { 2545 mutex_lock(&usb_port_peer_mutex); 2546 hcd->address0_mutex = primary_hcd->address0_mutex; 2547 hcd->bandwidth_mutex = primary_hcd->bandwidth_mutex; 2548 hcd->primary_hcd = primary_hcd; 2549 primary_hcd->primary_hcd = primary_hcd; 2550 hcd->shared_hcd = primary_hcd; 2551 primary_hcd->shared_hcd = hcd; 2552 mutex_unlock(&usb_port_peer_mutex); 2553 } 2554 2555 kref_init(&hcd->kref); 2556 2557 usb_bus_init(&hcd->self); 2558 hcd->self.controller = dev; 2559 hcd->self.bus_name = bus_name; 2560 hcd->self.uses_dma = (dev->dma_mask != NULL); 2561 2562 init_timer(&hcd->rh_timer); 2563 hcd->rh_timer.function = rh_timer_func; 2564 hcd->rh_timer.data = (unsigned long) hcd; 2565 #ifdef CONFIG_PM 2566 INIT_WORK(&hcd->wakeup_work, hcd_resume_work); 2567 #endif 2568 2569 hcd->driver = driver; 2570 hcd->speed = driver->flags & HCD_MASK; 2571 hcd->product_desc = (driver->product_desc) ? driver->product_desc : 2572 "USB Host Controller"; 2573 return hcd; 2574 } 2575 EXPORT_SYMBOL_GPL(usb_create_shared_hcd); 2576 2577 /** 2578 * usb_create_hcd - create and initialize an HCD structure 2579 * @driver: HC driver that will use this hcd 2580 * @dev: device for this HC, stored in hcd->self.controller 2581 * @bus_name: value to store in hcd->self.bus_name 2582 * Context: !in_interrupt() 2583 * 2584 * Allocate a struct usb_hcd, with extra space at the end for the 2585 * HC driver's private data. Initialize the generic members of the 2586 * hcd structure. 2587 * 2588 * Return: On success, a pointer to the created and initialized HCD 2589 * structure. On failure (e.g. if memory is unavailable), %NULL. 2590 */ 2591 struct usb_hcd *usb_create_hcd(const struct hc_driver *driver, 2592 struct device *dev, const char *bus_name) 2593 { 2594 return usb_create_shared_hcd(driver, dev, bus_name, NULL); 2595 } 2596 EXPORT_SYMBOL_GPL(usb_create_hcd); 2597 2598 /* 2599 * Roothubs that share one PCI device must also share the bandwidth mutex. 2600 * Don't deallocate the bandwidth_mutex until the last shared usb_hcd is 2601 * deallocated. 2602 * 2603 * Make sure to deallocate the bandwidth_mutex only when the last HCD is 2604 * freed. When hcd_release() is called for either hcd in a peer set, 2605 * invalidate the peer's ->shared_hcd and ->primary_hcd pointers. 2606 */ 2607 static void hcd_release(struct kref *kref) 2608 { 2609 struct usb_hcd *hcd = container_of (kref, struct usb_hcd, kref); 2610 2611 mutex_lock(&usb_port_peer_mutex); 2612 if (hcd->shared_hcd) { 2613 struct usb_hcd *peer = hcd->shared_hcd; 2614 2615 peer->shared_hcd = NULL; 2616 peer->primary_hcd = NULL; 2617 } else { 2618 kfree(hcd->address0_mutex); 2619 kfree(hcd->bandwidth_mutex); 2620 } 2621 mutex_unlock(&usb_port_peer_mutex); 2622 kfree(hcd); 2623 } 2624 2625 struct usb_hcd *usb_get_hcd (struct usb_hcd *hcd) 2626 { 2627 if (hcd) 2628 kref_get (&hcd->kref); 2629 return hcd; 2630 } 2631 EXPORT_SYMBOL_GPL(usb_get_hcd); 2632 2633 void usb_put_hcd (struct usb_hcd *hcd) 2634 { 2635 if (hcd) 2636 kref_put (&hcd->kref, hcd_release); 2637 } 2638 EXPORT_SYMBOL_GPL(usb_put_hcd); 2639 2640 int usb_hcd_is_primary_hcd(struct usb_hcd *hcd) 2641 { 2642 if (!hcd->primary_hcd) 2643 return 1; 2644 return hcd == hcd->primary_hcd; 2645 } 2646 EXPORT_SYMBOL_GPL(usb_hcd_is_primary_hcd); 2647 2648 int usb_hcd_find_raw_port_number(struct usb_hcd *hcd, int port1) 2649 { 2650 if (!hcd->driver->find_raw_port_number) 2651 return port1; 2652 2653 return hcd->driver->find_raw_port_number(hcd, port1); 2654 } 2655 2656 static int usb_hcd_request_irqs(struct usb_hcd *hcd, 2657 unsigned int irqnum, unsigned long irqflags) 2658 { 2659 int retval; 2660 2661 if (hcd->driver->irq) { 2662 2663 snprintf(hcd->irq_descr, sizeof(hcd->irq_descr), "%s:usb%d", 2664 hcd->driver->description, hcd->self.busnum); 2665 retval = request_irq(irqnum, &usb_hcd_irq, irqflags, 2666 hcd->irq_descr, hcd); 2667 if (retval != 0) { 2668 dev_err(hcd->self.controller, 2669 "request interrupt %d failed\n", 2670 irqnum); 2671 return retval; 2672 } 2673 hcd->irq = irqnum; 2674 dev_info(hcd->self.controller, "irq %d, %s 0x%08llx\n", irqnum, 2675 (hcd->driver->flags & HCD_MEMORY) ? 2676 "io mem" : "io base", 2677 (unsigned long long)hcd->rsrc_start); 2678 } else { 2679 hcd->irq = 0; 2680 if (hcd->rsrc_start) 2681 dev_info(hcd->self.controller, "%s 0x%08llx\n", 2682 (hcd->driver->flags & HCD_MEMORY) ? 2683 "io mem" : "io base", 2684 (unsigned long long)hcd->rsrc_start); 2685 } 2686 return 0; 2687 } 2688 2689 /* 2690 * Before we free this root hub, flush in-flight peering attempts 2691 * and disable peer lookups 2692 */ 2693 static void usb_put_invalidate_rhdev(struct usb_hcd *hcd) 2694 { 2695 struct usb_device *rhdev; 2696 2697 mutex_lock(&usb_port_peer_mutex); 2698 rhdev = hcd->self.root_hub; 2699 hcd->self.root_hub = NULL; 2700 mutex_unlock(&usb_port_peer_mutex); 2701 usb_put_dev(rhdev); 2702 } 2703 2704 /** 2705 * usb_add_hcd - finish generic HCD structure initialization and register 2706 * @hcd: the usb_hcd structure to initialize 2707 * @irqnum: Interrupt line to allocate 2708 * @irqflags: Interrupt type flags 2709 * 2710 * Finish the remaining parts of generic HCD initialization: allocate the 2711 * buffers of consistent memory, register the bus, request the IRQ line, 2712 * and call the driver's reset() and start() routines. 2713 */ 2714 int usb_add_hcd(struct usb_hcd *hcd, 2715 unsigned int irqnum, unsigned long irqflags) 2716 { 2717 int retval; 2718 struct usb_device *rhdev; 2719 2720 if (IS_ENABLED(CONFIG_USB_PHY) && !hcd->usb_phy) { 2721 struct usb_phy *phy = usb_get_phy_dev(hcd->self.controller, 0); 2722 2723 if (IS_ERR(phy)) { 2724 retval = PTR_ERR(phy); 2725 if (retval == -EPROBE_DEFER) 2726 return retval; 2727 } else { 2728 retval = usb_phy_init(phy); 2729 if (retval) { 2730 usb_put_phy(phy); 2731 return retval; 2732 } 2733 hcd->usb_phy = phy; 2734 hcd->remove_phy = 1; 2735 } 2736 } 2737 2738 if (IS_ENABLED(CONFIG_GENERIC_PHY) && !hcd->phy) { 2739 struct phy *phy = phy_get(hcd->self.controller, "usb"); 2740 2741 if (IS_ERR(phy)) { 2742 retval = PTR_ERR(phy); 2743 if (retval == -EPROBE_DEFER) 2744 goto err_phy; 2745 } else { 2746 retval = phy_init(phy); 2747 if (retval) { 2748 phy_put(phy); 2749 goto err_phy; 2750 } 2751 retval = phy_power_on(phy); 2752 if (retval) { 2753 phy_exit(phy); 2754 phy_put(phy); 2755 goto err_phy; 2756 } 2757 hcd->phy = phy; 2758 hcd->remove_phy = 1; 2759 } 2760 } 2761 2762 dev_info(hcd->self.controller, "%s\n", hcd->product_desc); 2763 2764 /* Keep old behaviour if authorized_default is not in [0, 1]. */ 2765 if (authorized_default < 0 || authorized_default > 1) { 2766 if (hcd->wireless) 2767 clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 2768 else 2769 set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 2770 } else { 2771 if (authorized_default) 2772 set_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 2773 else 2774 clear_bit(HCD_FLAG_DEV_AUTHORIZED, &hcd->flags); 2775 } 2776 set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); 2777 2778 /* per default all interfaces are authorized */ 2779 set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags); 2780 2781 /* HC is in reset state, but accessible. Now do the one-time init, 2782 * bottom up so that hcds can customize the root hubs before hub_wq 2783 * starts talking to them. (Note, bus id is assigned early too.) 2784 */ 2785 retval = hcd_buffer_create(hcd); 2786 if (retval != 0) { 2787 dev_dbg(hcd->self.controller, "pool alloc failed\n"); 2788 goto err_create_buf; 2789 } 2790 2791 retval = usb_register_bus(&hcd->self); 2792 if (retval < 0) 2793 goto err_register_bus; 2794 2795 rhdev = usb_alloc_dev(NULL, &hcd->self, 0); 2796 if (rhdev == NULL) { 2797 dev_err(hcd->self.controller, "unable to allocate root hub\n"); 2798 retval = -ENOMEM; 2799 goto err_allocate_root_hub; 2800 } 2801 mutex_lock(&usb_port_peer_mutex); 2802 hcd->self.root_hub = rhdev; 2803 mutex_unlock(&usb_port_peer_mutex); 2804 2805 switch (hcd->speed) { 2806 case HCD_USB11: 2807 rhdev->speed = USB_SPEED_FULL; 2808 break; 2809 case HCD_USB2: 2810 rhdev->speed = USB_SPEED_HIGH; 2811 break; 2812 case HCD_USB25: 2813 rhdev->speed = USB_SPEED_WIRELESS; 2814 break; 2815 case HCD_USB3: 2816 rhdev->speed = USB_SPEED_SUPER; 2817 break; 2818 case HCD_USB31: 2819 rhdev->speed = USB_SPEED_SUPER_PLUS; 2820 break; 2821 default: 2822 retval = -EINVAL; 2823 goto err_set_rh_speed; 2824 } 2825 2826 /* wakeup flag init defaults to "everything works" for root hubs, 2827 * but drivers can override it in reset() if needed, along with 2828 * recording the overall controller's system wakeup capability. 2829 */ 2830 device_set_wakeup_capable(&rhdev->dev, 1); 2831 2832 /* HCD_FLAG_RH_RUNNING doesn't matter until the root hub is 2833 * registered. But since the controller can die at any time, 2834 * let's initialize the flag before touching the hardware. 2835 */ 2836 set_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2837 2838 /* "reset" is misnamed; its role is now one-time init. the controller 2839 * should already have been reset (and boot firmware kicked off etc). 2840 */ 2841 if (hcd->driver->reset) { 2842 retval = hcd->driver->reset(hcd); 2843 if (retval < 0) { 2844 dev_err(hcd->self.controller, "can't setup: %d\n", 2845 retval); 2846 goto err_hcd_driver_setup; 2847 } 2848 } 2849 hcd->rh_pollable = 1; 2850 2851 /* NOTE: root hub and controller capabilities may not be the same */ 2852 if (device_can_wakeup(hcd->self.controller) 2853 && device_can_wakeup(&hcd->self.root_hub->dev)) 2854 dev_dbg(hcd->self.controller, "supports USB remote wakeup\n"); 2855 2856 /* initialize tasklets */ 2857 init_giveback_urb_bh(&hcd->high_prio_bh); 2858 init_giveback_urb_bh(&hcd->low_prio_bh); 2859 2860 /* enable irqs just before we start the controller, 2861 * if the BIOS provides legacy PCI irqs. 2862 */ 2863 if (usb_hcd_is_primary_hcd(hcd) && irqnum) { 2864 retval = usb_hcd_request_irqs(hcd, irqnum, irqflags); 2865 if (retval) 2866 goto err_request_irq; 2867 } 2868 2869 hcd->state = HC_STATE_RUNNING; 2870 retval = hcd->driver->start(hcd); 2871 if (retval < 0) { 2872 dev_err(hcd->self.controller, "startup error %d\n", retval); 2873 goto err_hcd_driver_start; 2874 } 2875 2876 /* starting here, usbcore will pay attention to this root hub */ 2877 retval = register_root_hub(hcd); 2878 if (retval != 0) 2879 goto err_register_root_hub; 2880 2881 retval = sysfs_create_group(&rhdev->dev.kobj, &usb_bus_attr_group); 2882 if (retval < 0) { 2883 printk(KERN_ERR "Cannot register USB bus sysfs attributes: %d\n", 2884 retval); 2885 goto error_create_attr_group; 2886 } 2887 if (hcd->uses_new_polling && HCD_POLL_RH(hcd)) 2888 usb_hcd_poll_rh_status(hcd); 2889 2890 return retval; 2891 2892 error_create_attr_group: 2893 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2894 if (HC_IS_RUNNING(hcd->state)) 2895 hcd->state = HC_STATE_QUIESCING; 2896 spin_lock_irq(&hcd_root_hub_lock); 2897 hcd->rh_registered = 0; 2898 spin_unlock_irq(&hcd_root_hub_lock); 2899 2900 #ifdef CONFIG_PM 2901 cancel_work_sync(&hcd->wakeup_work); 2902 #endif 2903 mutex_lock(&usb_bus_idr_lock); 2904 usb_disconnect(&rhdev); /* Sets rhdev to NULL */ 2905 mutex_unlock(&usb_bus_idr_lock); 2906 err_register_root_hub: 2907 hcd->rh_pollable = 0; 2908 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2909 del_timer_sync(&hcd->rh_timer); 2910 hcd->driver->stop(hcd); 2911 hcd->state = HC_STATE_HALT; 2912 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2913 del_timer_sync(&hcd->rh_timer); 2914 err_hcd_driver_start: 2915 if (usb_hcd_is_primary_hcd(hcd) && hcd->irq > 0) 2916 free_irq(irqnum, hcd); 2917 err_request_irq: 2918 err_hcd_driver_setup: 2919 err_set_rh_speed: 2920 usb_put_invalidate_rhdev(hcd); 2921 err_allocate_root_hub: 2922 usb_deregister_bus(&hcd->self); 2923 err_register_bus: 2924 hcd_buffer_destroy(hcd); 2925 err_create_buf: 2926 if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) { 2927 phy_power_off(hcd->phy); 2928 phy_exit(hcd->phy); 2929 phy_put(hcd->phy); 2930 hcd->phy = NULL; 2931 } 2932 err_phy: 2933 if (hcd->remove_phy && hcd->usb_phy) { 2934 usb_phy_shutdown(hcd->usb_phy); 2935 usb_put_phy(hcd->usb_phy); 2936 hcd->usb_phy = NULL; 2937 } 2938 return retval; 2939 } 2940 EXPORT_SYMBOL_GPL(usb_add_hcd); 2941 2942 /** 2943 * usb_remove_hcd - shutdown processing for generic HCDs 2944 * @hcd: the usb_hcd structure to remove 2945 * Context: !in_interrupt() 2946 * 2947 * Disconnects the root hub, then reverses the effects of usb_add_hcd(), 2948 * invoking the HCD's stop() method. 2949 */ 2950 void usb_remove_hcd(struct usb_hcd *hcd) 2951 { 2952 struct usb_device *rhdev = hcd->self.root_hub; 2953 2954 dev_info(hcd->self.controller, "remove, state %x\n", hcd->state); 2955 2956 usb_get_dev(rhdev); 2957 sysfs_remove_group(&rhdev->dev.kobj, &usb_bus_attr_group); 2958 2959 clear_bit(HCD_FLAG_RH_RUNNING, &hcd->flags); 2960 if (HC_IS_RUNNING (hcd->state)) 2961 hcd->state = HC_STATE_QUIESCING; 2962 2963 dev_dbg(hcd->self.controller, "roothub graceful disconnect\n"); 2964 spin_lock_irq (&hcd_root_hub_lock); 2965 hcd->rh_registered = 0; 2966 spin_unlock_irq (&hcd_root_hub_lock); 2967 2968 #ifdef CONFIG_PM 2969 cancel_work_sync(&hcd->wakeup_work); 2970 #endif 2971 2972 mutex_lock(&usb_bus_idr_lock); 2973 usb_disconnect(&rhdev); /* Sets rhdev to NULL */ 2974 mutex_unlock(&usb_bus_idr_lock); 2975 2976 /* 2977 * tasklet_kill() isn't needed here because: 2978 * - driver's disconnect() called from usb_disconnect() should 2979 * make sure its URBs are completed during the disconnect() 2980 * callback 2981 * 2982 * - it is too late to run complete() here since driver may have 2983 * been removed already now 2984 */ 2985 2986 /* Prevent any more root-hub status calls from the timer. 2987 * The HCD might still restart the timer (if a port status change 2988 * interrupt occurs), but usb_hcd_poll_rh_status() won't invoke 2989 * the hub_status_data() callback. 2990 */ 2991 hcd->rh_pollable = 0; 2992 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 2993 del_timer_sync(&hcd->rh_timer); 2994 2995 hcd->driver->stop(hcd); 2996 hcd->state = HC_STATE_HALT; 2997 2998 /* In case the HCD restarted the timer, stop it again. */ 2999 clear_bit(HCD_FLAG_POLL_RH, &hcd->flags); 3000 del_timer_sync(&hcd->rh_timer); 3001 3002 if (usb_hcd_is_primary_hcd(hcd)) { 3003 if (hcd->irq > 0) 3004 free_irq(hcd->irq, hcd); 3005 } 3006 3007 usb_deregister_bus(&hcd->self); 3008 hcd_buffer_destroy(hcd); 3009 3010 if (IS_ENABLED(CONFIG_GENERIC_PHY) && hcd->remove_phy && hcd->phy) { 3011 phy_power_off(hcd->phy); 3012 phy_exit(hcd->phy); 3013 phy_put(hcd->phy); 3014 hcd->phy = NULL; 3015 } 3016 if (hcd->remove_phy && hcd->usb_phy) { 3017 usb_phy_shutdown(hcd->usb_phy); 3018 usb_put_phy(hcd->usb_phy); 3019 hcd->usb_phy = NULL; 3020 } 3021 3022 usb_put_invalidate_rhdev(hcd); 3023 hcd->flags = 0; 3024 } 3025 EXPORT_SYMBOL_GPL(usb_remove_hcd); 3026 3027 void 3028 usb_hcd_platform_shutdown(struct platform_device *dev) 3029 { 3030 struct usb_hcd *hcd = platform_get_drvdata(dev); 3031 3032 if (hcd->driver->shutdown) 3033 hcd->driver->shutdown(hcd); 3034 } 3035 EXPORT_SYMBOL_GPL(usb_hcd_platform_shutdown); 3036 3037 /*-------------------------------------------------------------------------*/ 3038 3039 #if IS_ENABLED(CONFIG_USB_MON) 3040 3041 const struct usb_mon_operations *mon_ops; 3042 3043 /* 3044 * The registration is unlocked. 3045 * We do it this way because we do not want to lock in hot paths. 3046 * 3047 * Notice that the code is minimally error-proof. Because usbmon needs 3048 * symbols from usbcore, usbcore gets referenced and cannot be unloaded first. 3049 */ 3050 3051 int usb_mon_register(const struct usb_mon_operations *ops) 3052 { 3053 3054 if (mon_ops) 3055 return -EBUSY; 3056 3057 mon_ops = ops; 3058 mb(); 3059 return 0; 3060 } 3061 EXPORT_SYMBOL_GPL (usb_mon_register); 3062 3063 void usb_mon_deregister (void) 3064 { 3065 3066 if (mon_ops == NULL) { 3067 printk(KERN_ERR "USB: monitor was not registered\n"); 3068 return; 3069 } 3070 mon_ops = NULL; 3071 mb(); 3072 } 3073 EXPORT_SYMBOL_GPL (usb_mon_deregister); 3074 3075 #endif /* CONFIG_USB_MON || CONFIG_USB_MON_MODULE */ 3076