blob: fefb92296e8f5a921edf849a30caf808cf904793 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * message.c - synchronous message handling
3 */
4
Linus Torvalds1da177e2005-04-16 15:20:36 -07005#include <linux/pci.h> /* for scatterlist macros */
6#include <linux/usb.h>
7#include <linux/module.h>
8#include <linux/slab.h>
9#include <linux/init.h>
10#include <linux/mm.h>
11#include <linux/timer.h>
12#include <linux/ctype.h>
13#include <linux/device.h>
Ralf Baechle11763602007-10-23 20:42:11 +020014#include <linux/scatterlist.h>
Oliver Neukum7ceec1f2007-01-26 14:26:21 +010015#include <linux/usb/quirks.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <asm/byteorder.h>
17
18#include "hcd.h" /* for usbcore internals */
19#include "usb.h"
20
Alan Stern67f5dde2007-07-24 18:23:23 -040021struct api_context {
22 struct completion done;
23 int status;
24};
25
David Howells7d12e782006-10-05 14:55:46 +010026static void usb_api_blocking_completion(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -070027{
Alan Stern67f5dde2007-07-24 18:23:23 -040028 struct api_context *ctx = urb->context;
29
30 ctx->status = urb->status;
31 complete(&ctx->done);
Linus Torvalds1da177e2005-04-16 15:20:36 -070032}
33
34
Franck Bui-Huuecdc0a52006-07-12 10:09:41 +020035/*
36 * Starts urb and waits for completion or timeout. Note that this call
37 * is NOT interruptible. Many device driver i/o requests should be
38 * interruptible and therefore these drivers should implement their
39 * own interruptible routines.
40 */
41static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length)
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -080042{
Alan Stern67f5dde2007-07-24 18:23:23 -040043 struct api_context ctx;
Franck Bui-Huuecdc0a52006-07-12 10:09:41 +020044 unsigned long expire;
Greg Kroah-Hartman3fc3e822007-07-18 10:58:02 -070045 int retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
Alan Stern67f5dde2007-07-24 18:23:23 -040047 init_completion(&ctx.done);
48 urb->context = &ctx;
Linus Torvalds1da177e2005-04-16 15:20:36 -070049 urb->actual_length = 0;
Greg Kroah-Hartman3fc3e822007-07-18 10:58:02 -070050 retval = usb_submit_urb(urb, GFP_NOIO);
51 if (unlikely(retval))
Franck Bui-Huuecdc0a52006-07-12 10:09:41 +020052 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -070053
Franck Bui-Huuecdc0a52006-07-12 10:09:41 +020054 expire = timeout ? msecs_to_jiffies(timeout) : MAX_SCHEDULE_TIMEOUT;
Alan Stern67f5dde2007-07-24 18:23:23 -040055 if (!wait_for_completion_timeout(&ctx.done, expire)) {
56 usb_kill_urb(urb);
57 retval = (ctx.status == -ENOENT ? -ETIMEDOUT : ctx.status);
Franck Bui-Huuecdc0a52006-07-12 10:09:41 +020058
59 dev_dbg(&urb->dev->dev,
60 "%s timed out on ep%d%s len=%d/%d\n",
61 current->comm,
Alan Stern5e60a162007-07-30 17:07:21 -040062 usb_endpoint_num(&urb->ep->desc),
63 usb_urb_dir_in(urb) ? "in" : "out",
Franck Bui-Huuecdc0a52006-07-12 10:09:41 +020064 urb->actual_length,
65 urb->transfer_buffer_length);
Franck Bui-Huuecdc0a52006-07-12 10:09:41 +020066 } else
Alan Stern67f5dde2007-07-24 18:23:23 -040067 retval = ctx.status;
Franck Bui-Huuecdc0a52006-07-12 10:09:41 +020068out:
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 if (actual_length)
70 *actual_length = urb->actual_length;
Franck Bui-Huuecdc0a52006-07-12 10:09:41 +020071
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 usb_free_urb(urb);
Greg Kroah-Hartman3fc3e822007-07-18 10:58:02 -070073 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -070074}
75
76/*-------------------------------------------------------------------*/
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -080077/* returns status (negative) or length (positive) */
Linus Torvalds1da177e2005-04-16 15:20:36 -070078static int usb_internal_control_msg(struct usb_device *usb_dev,
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -080079 unsigned int pipe,
Linus Torvalds1da177e2005-04-16 15:20:36 -070080 struct usb_ctrlrequest *cmd,
81 void *data, int len, int timeout)
82{
83 struct urb *urb;
84 int retv;
85 int length;
86
87 urb = usb_alloc_urb(0, GFP_NOIO);
88 if (!urb)
89 return -ENOMEM;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -080090
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 usb_fill_control_urb(urb, usb_dev, pipe, (unsigned char *)cmd, data,
92 len, usb_api_blocking_completion, NULL);
93
94 retv = usb_start_wait_urb(urb, timeout, &length);
95 if (retv < 0)
96 return retv;
97 else
98 return length;
99}
100
101/**
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800102 * usb_control_msg - Builds a control urb, sends it off and waits for completion
103 * @dev: pointer to the usb device to send the message to
104 * @pipe: endpoint "pipe" to send the message to
105 * @request: USB message request value
106 * @requesttype: USB message request type value
107 * @value: USB message value
108 * @index: USB message index value
109 * @data: pointer to the data to send
110 * @size: length in bytes of the data to send
111 * @timeout: time in msecs to wait for the message to complete before timing
112 * out (if 0 the wait is forever)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113 *
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800114 * Context: !in_interrupt ()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 *
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800116 * This function sends a simple control message to a specified endpoint and
117 * waits for the message to complete, or timeout.
118 *
119 * If successful, it returns the number of bytes transferred, otherwise a
120 * negative error number.
121 *
122 * Don't use this function from within an interrupt context, like a bottom half
123 * handler. If you need an asynchronous message, or need to send a message
124 * from within interrupt context, use usb_submit_urb().
125 * If a thread in your driver uses this call, make sure your disconnect()
126 * method can wait for it to complete. Since you don't have a handle on the
127 * URB used, you can't cancel the request.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128 */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800129int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request,
130 __u8 requesttype, __u16 value, __u16 index, void *data,
131 __u16 size, int timeout)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132{
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800133 struct usb_ctrlrequest *dr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 int ret;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800135
136 dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 if (!dr)
138 return -ENOMEM;
139
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800140 dr->bRequestType = requesttype;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141 dr->bRequest = request;
142 dr->wValue = cpu_to_le16p(&value);
143 dr->wIndex = cpu_to_le16p(&index);
144 dr->wLength = cpu_to_le16p(&size);
145
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800146 /* dbg("usb_control_msg"); */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147
148 ret = usb_internal_control_msg(dev, pipe, dr, data, size, timeout);
149
150 kfree(dr);
151
152 return ret;
153}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600154EXPORT_SYMBOL_GPL(usb_control_msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155
156/**
Greg Kroah-Hartman782a7a62006-05-19 13:20:20 -0700157 * usb_interrupt_msg - Builds an interrupt urb, sends it off and waits for completion
158 * @usb_dev: pointer to the usb device to send the message to
159 * @pipe: endpoint "pipe" to send the message to
160 * @data: pointer to the data to send
161 * @len: length in bytes of the data to send
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800162 * @actual_length: pointer to a location to put the actual length transferred
163 * in bytes
Greg Kroah-Hartman782a7a62006-05-19 13:20:20 -0700164 * @timeout: time in msecs to wait for the message to complete before
165 * timing out (if 0 the wait is forever)
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800166 *
Greg Kroah-Hartman782a7a62006-05-19 13:20:20 -0700167 * Context: !in_interrupt ()
168 *
169 * This function sends a simple interrupt message to a specified endpoint and
170 * waits for the message to complete, or timeout.
171 *
172 * If successful, it returns 0, otherwise a negative error number. The number
173 * of actual bytes transferred will be stored in the actual_length paramater.
174 *
175 * Don't use this function from within an interrupt context, like a bottom half
176 * handler. If you need an asynchronous message, or need to send a message
177 * from within interrupt context, use usb_submit_urb() If a thread in your
178 * driver uses this call, make sure your disconnect() method can wait for it to
179 * complete. Since you don't have a handle on the URB used, you can't cancel
180 * the request.
181 */
182int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe,
183 void *data, int len, int *actual_length, int timeout)
184{
185 return usb_bulk_msg(usb_dev, pipe, data, len, actual_length, timeout);
186}
187EXPORT_SYMBOL_GPL(usb_interrupt_msg);
188
189/**
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800190 * usb_bulk_msg - Builds a bulk urb, sends it off and waits for completion
191 * @usb_dev: pointer to the usb device to send the message to
192 * @pipe: endpoint "pipe" to send the message to
193 * @data: pointer to the data to send
194 * @len: length in bytes of the data to send
195 * @actual_length: pointer to a location to put the actual length transferred
196 * in bytes
197 * @timeout: time in msecs to wait for the message to complete before
198 * timing out (if 0 the wait is forever)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 *
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800200 * Context: !in_interrupt ()
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201 *
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800202 * This function sends a simple bulk message to a specified endpoint
203 * and waits for the message to complete, or timeout.
Alan Sternd09d36a2005-09-26 16:22:45 -0400204 *
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800205 * If successful, it returns 0, otherwise a negative error number. The number
206 * of actual bytes transferred will be stored in the actual_length paramater.
207 *
208 * Don't use this function from within an interrupt context, like a bottom half
209 * handler. If you need an asynchronous message, or need to send a message
210 * from within interrupt context, use usb_submit_urb() If a thread in your
211 * driver uses this call, make sure your disconnect() method can wait for it to
212 * complete. Since you don't have a handle on the URB used, you can't cancel
213 * the request.
214 *
215 * Because there is no usb_interrupt_msg() and no USBDEVFS_INTERRUPT ioctl,
216 * users are forced to abuse this routine by using it to submit URBs for
217 * interrupt endpoints. We will take the liberty of creating an interrupt URB
218 * (with the default interval) if the target is an interrupt endpoint.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800220int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe,
221 void *data, int len, int *actual_length, int timeout)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222{
223 struct urb *urb;
Alan Sternd09d36a2005-09-26 16:22:45 -0400224 struct usb_host_endpoint *ep;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225
Alan Sternd09d36a2005-09-26 16:22:45 -0400226 ep = (usb_pipein(pipe) ? usb_dev->ep_in : usb_dev->ep_out)
227 [usb_pipeendpoint(pipe)];
228 if (!ep || len < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229 return -EINVAL;
230
Alan Sternd09d36a2005-09-26 16:22:45 -0400231 urb = usb_alloc_urb(0, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232 if (!urb)
233 return -ENOMEM;
234
Alan Sternd09d36a2005-09-26 16:22:45 -0400235 if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
236 USB_ENDPOINT_XFER_INT) {
237 pipe = (pipe & ~(3 << 30)) | (PIPE_INTERRUPT << 30);
238 usb_fill_int_urb(urb, usb_dev, pipe, data, len,
Alan Stern8d062b92007-04-23 17:30:32 -0400239 usb_api_blocking_completion, NULL,
240 ep->desc.bInterval);
Alan Sternd09d36a2005-09-26 16:22:45 -0400241 } else
242 usb_fill_bulk_urb(urb, usb_dev, pipe, data, len,
243 usb_api_blocking_completion, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244
245 return usb_start_wait_urb(urb, timeout, actual_length);
246}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600247EXPORT_SYMBOL_GPL(usb_bulk_msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248
249/*-------------------------------------------------------------------*/
250
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800251static void sg_clean(struct usb_sg_request *io)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252{
253 if (io->urbs) {
254 while (io->entries--)
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800255 usb_free_urb(io->urbs [io->entries]);
256 kfree(io->urbs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257 io->urbs = NULL;
258 }
259 if (io->dev->dev.dma_mask != NULL)
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800260 usb_buffer_unmap_sg(io->dev, usb_pipein(io->pipe),
261 io->sg, io->nents);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700262 io->dev = NULL;
263}
264
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800265static void sg_complete(struct urb *urb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266{
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800267 struct usb_sg_request *io = urb->context;
Greg Kroah-Hartman3fc3e822007-07-18 10:58:02 -0700268 int status = urb->status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800270 spin_lock(&io->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271
272 /* In 2.5 we require hcds' endpoint queues not to progress after fault
273 * reports, until the completion callback (this!) returns. That lets
274 * device driver code (like this routine) unlink queued urbs first,
275 * if it needs to, since the HC won't work on them at all. So it's
276 * not possible for page N+1 to overwrite page N, and so on.
277 *
278 * That's only for "hard" faults; "soft" faults (unlinks) sometimes
279 * complete before the HCD can get requests away from hardware,
280 * though never during cleanup after a hard fault.
281 */
282 if (io->status
283 && (io->status != -ECONNRESET
Greg Kroah-Hartman3fc3e822007-07-18 10:58:02 -0700284 || status != -ECONNRESET)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700285 && urb->actual_length) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800286 dev_err(io->dev->bus->controller,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 "dev %s ep%d%s scatterlist error %d/%d\n",
288 io->dev->devpath,
Alan Stern5e60a162007-07-30 17:07:21 -0400289 usb_endpoint_num(&urb->ep->desc),
290 usb_urb_dir_in(urb) ? "in" : "out",
Greg Kroah-Hartman3fc3e822007-07-18 10:58:02 -0700291 status, io->status);
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800292 /* BUG (); */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293 }
294
Greg Kroah-Hartman3fc3e822007-07-18 10:58:02 -0700295 if (io->status == 0 && status && status != -ECONNRESET) {
296 int i, found, retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297
Greg Kroah-Hartman3fc3e822007-07-18 10:58:02 -0700298 io->status = status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299
300 /* the previous urbs, and this one, completed already.
301 * unlink pending urbs so they won't rx/tx bad data.
302 * careful: unlink can sometimes be synchronous...
303 */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800304 spin_unlock(&io->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305 for (i = 0, found = 0; i < io->entries; i++) {
306 if (!io->urbs [i] || !io->urbs [i]->dev)
307 continue;
308 if (found) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800309 retval = usb_unlink_urb(io->urbs [i]);
Greg Kroah-Hartman3fc3e822007-07-18 10:58:02 -0700310 if (retval != -EINPROGRESS &&
311 retval != -ENODEV &&
312 retval != -EBUSY)
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800313 dev_err(&io->dev->dev,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 "%s, unlink --> %d\n",
Greg Kroah-Hartman3fc3e822007-07-18 10:58:02 -0700315 __FUNCTION__, retval);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316 } else if (urb == io->urbs [i])
317 found = 1;
318 }
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800319 spin_lock(&io->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 }
321 urb->dev = NULL;
322
323 /* on the last completion, signal usb_sg_wait() */
324 io->bytes += urb->actual_length;
325 io->count--;
326 if (!io->count)
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800327 complete(&io->complete);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800329 spin_unlock(&io->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330}
331
332
333/**
334 * usb_sg_init - initializes scatterlist-based bulk/interrupt I/O request
335 * @io: request block being initialized. until usb_sg_wait() returns,
336 * treat this as a pointer to an opaque block of memory,
337 * @dev: the usb device that will send or receive the data
338 * @pipe: endpoint "pipe" used to transfer the data
339 * @period: polling rate for interrupt endpoints, in frames or
340 * (for high speed endpoints) microframes; ignored for bulk
341 * @sg: scatterlist entries
342 * @nents: how many entries in the scatterlist
343 * @length: how many bytes to send from the scatterlist, or zero to
344 * send every byte identified in the list.
345 * @mem_flags: SLAB_* flags affecting memory allocations in this call
346 *
347 * Returns zero for success, else a negative errno value. This initializes a
348 * scatter/gather request, allocating resources such as I/O mappings and urb
349 * memory (except maybe memory used by USB controller drivers).
350 *
351 * The request must be issued using usb_sg_wait(), which waits for the I/O to
352 * complete (or to be canceled) and then cleans up all resources allocated by
353 * usb_sg_init().
354 *
355 * The request may be canceled with usb_sg_cancel(), either before or after
356 * usb_sg_wait() is called.
357 */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800358int usb_sg_init(struct usb_sg_request *io, struct usb_device *dev,
359 unsigned pipe, unsigned period, struct scatterlist *sg,
360 int nents, size_t length, gfp_t mem_flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361{
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800362 int i;
363 int urb_flags;
364 int dma;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365
366 if (!io || !dev || !sg
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800367 || usb_pipecontrol(pipe)
368 || usb_pipeisoc(pipe)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 || nents <= 0)
370 return -EINVAL;
371
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800372 spin_lock_init(&io->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373 io->dev = dev;
374 io->pipe = pipe;
375 io->sg = sg;
376 io->nents = nents;
377
378 /* not all host controllers use DMA (like the mainstream pci ones);
379 * they can use PIO (sl811) or be software over another transport.
380 */
381 dma = (dev->dev.dma_mask != NULL);
382 if (dma)
Alan Stern5e60a162007-07-30 17:07:21 -0400383 io->entries = usb_buffer_map_sg(dev, usb_pipein(pipe),
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800384 sg, nents);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 else
386 io->entries = nents;
387
388 /* initialize all the urbs we'll use */
389 if (io->entries <= 0)
390 return io->entries;
391
392 io->count = io->entries;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800393 io->urbs = kmalloc(io->entries * sizeof *io->urbs, mem_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394 if (!io->urbs)
395 goto nomem;
396
Alan Sternb375a042005-07-29 16:11:07 -0400397 urb_flags = URB_NO_TRANSFER_DMA_MAP | URB_NO_INTERRUPT;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800398 if (usb_pipein(pipe))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399 urb_flags |= URB_SHORT_NOT_OK;
400
401 for (i = 0; i < io->entries; i++) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800402 unsigned len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800404 io->urbs[i] = usb_alloc_urb(0, mem_flags);
405 if (!io->urbs[i]) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406 io->entries = i;
407 goto nomem;
408 }
409
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800410 io->urbs[i]->dev = NULL;
411 io->urbs[i]->pipe = pipe;
412 io->urbs[i]->interval = period;
413 io->urbs[i]->transfer_flags = urb_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800415 io->urbs[i]->complete = sg_complete;
416 io->urbs[i]->context = io;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417
Tony Lindgren35d07fd2007-03-31 18:15:43 -0700418 /*
419 * Some systems need to revert to PIO when DMA is temporarily
420 * unavailable. For their sakes, both transfer_buffer and
421 * transfer_dma are set when possible. However this can only
David Brownella12b8db2007-07-22 15:13:13 -0700422 * work on systems without:
423 *
424 * - HIGHMEM, since DMA buffers located in high memory are
425 * not directly addressable by the CPU for PIO;
426 *
427 * - IOMMU, since dma_map_sg() is allowed to use an IOMMU to
428 * make virtually discontiguous buffers be "dma-contiguous"
429 * so that PIO and DMA need diferent numbers of URBs.
430 *
431 * So when HIGHMEM or IOMMU are in use, transfer_buffer is NULL
Tony Lindgren35d07fd2007-03-31 18:15:43 -0700432 * to prevent stale pointers and to help spot bugs.
433 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700434 if (dma) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800435 io->urbs[i]->transfer_dma = sg_dma_address(sg + i);
436 len = sg_dma_len(sg + i);
Joerg Roedel966396d2007-10-24 12:49:48 +0200437#if defined(CONFIG_HIGHMEM) || defined(CONFIG_GART_IOMMU)
Tony Lindgren35d07fd2007-03-31 18:15:43 -0700438 io->urbs[i]->transfer_buffer = NULL;
439#else
Jens Axboe45711f12007-10-22 21:19:53 +0200440 io->urbs[i]->transfer_buffer = sg_virt(&sg[i]);
Tony Lindgren35d07fd2007-03-31 18:15:43 -0700441#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442 } else {
443 /* hc may use _only_ transfer_buffer */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800444 io->urbs[i]->transfer_buffer = sg_virt(&sg[i]);
445 len = sg[i].length;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 }
447
448 if (length) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800449 len = min_t(unsigned, len, length);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 length -= len;
451 if (length == 0)
452 io->entries = i + 1;
453 }
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800454 io->urbs[i]->transfer_buffer_length = len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455 }
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800456 io->urbs[--i]->transfer_flags &= ~URB_NO_INTERRUPT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457
458 /* transaction state */
459 io->status = 0;
460 io->bytes = 0;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800461 init_completion(&io->complete);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 return 0;
463
464nomem:
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800465 sg_clean(io);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 return -ENOMEM;
467}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600468EXPORT_SYMBOL_GPL(usb_sg_init);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469
470/**
471 * usb_sg_wait - synchronously execute scatter/gather request
472 * @io: request block handle, as initialized with usb_sg_init().
473 * some fields become accessible when this call returns.
474 * Context: !in_interrupt ()
475 *
476 * This function blocks until the specified I/O operation completes. It
477 * leverages the grouping of the related I/O requests to get good transfer
478 * rates, by queueing the requests. At higher speeds, such queuing can
479 * significantly improve USB throughput.
480 *
481 * There are three kinds of completion for this function.
482 * (1) success, where io->status is zero. The number of io->bytes
483 * transferred is as requested.
484 * (2) error, where io->status is a negative errno value. The number
485 * of io->bytes transferred before the error is usually less
486 * than requested, and can be nonzero.
Steven Cole093cf722005-05-03 19:07:24 -0600487 * (3) cancellation, a type of error with status -ECONNRESET that
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488 * is initiated by usb_sg_cancel().
489 *
490 * When this function returns, all memory allocated through usb_sg_init() or
491 * this call will have been freed. The request block parameter may still be
492 * passed to usb_sg_cancel(), or it may be freed. It could also be
493 * reinitialized and then reused.
494 *
495 * Data Transfer Rates:
496 *
497 * Bulk transfers are valid for full or high speed endpoints.
498 * The best full speed data rate is 19 packets of 64 bytes each
499 * per frame, or 1216 bytes per millisecond.
500 * The best high speed data rate is 13 packets of 512 bytes each
501 * per microframe, or 52 KBytes per millisecond.
502 *
503 * The reason to use interrupt transfers through this API would most likely
504 * be to reserve high speed bandwidth, where up to 24 KBytes per millisecond
505 * could be transferred. That capability is less useful for low or full
506 * speed interrupt endpoints, which allow at most one packet per millisecond,
507 * of at most 8 or 64 bytes (respectively).
508 */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800509void usb_sg_wait(struct usb_sg_request *io)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510{
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800511 int i;
512 int entries = io->entries;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513
514 /* queue the urbs. */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800515 spin_lock_irq(&io->lock);
Alan Stern8ccef0d2007-06-21 16:26:46 -0400516 i = 0;
517 while (i < entries && !io->status) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800518 int retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800520 io->urbs[i]->dev = io->dev;
521 retval = usb_submit_urb(io->urbs [i], GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522
523 /* after we submit, let completions or cancelations fire;
524 * we handshake using io->status.
525 */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800526 spin_unlock_irq(&io->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 switch (retval) {
528 /* maybe we retrying will recover */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800529 case -ENXIO: /* hc didn't queue this one */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 case -EAGAIN:
531 case -ENOMEM:
532 io->urbs[i]->dev = NULL;
533 retval = 0;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800534 yield();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 break;
536
537 /* no error? continue immediately.
538 *
539 * NOTE: to work better with UHCI (4K I/O buffer may
540 * need 3K of TDs) it may be good to limit how many
541 * URBs are queued at once; N milliseconds?
542 */
543 case 0:
Alan Stern8ccef0d2007-06-21 16:26:46 -0400544 ++i;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800545 cpu_relax();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 break;
547
548 /* fail any uncompleted urbs */
549 default:
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800550 io->urbs[i]->dev = NULL;
551 io->urbs[i]->status = retval;
552 dev_dbg(&io->dev->dev, "%s, submit --> %d\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553 __FUNCTION__, retval);
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800554 usb_sg_cancel(io);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 }
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800556 spin_lock_irq(&io->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 if (retval && (io->status == 0 || io->status == -ECONNRESET))
558 io->status = retval;
559 }
560 io->count -= entries - i;
561 if (io->count == 0)
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800562 complete(&io->complete);
563 spin_unlock_irq(&io->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564
565 /* OK, yes, this could be packaged as non-blocking.
566 * So could the submit loop above ... but it's easier to
567 * solve neither problem than to solve both!
568 */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800569 wait_for_completion(&io->complete);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800571 sg_clean(io);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600573EXPORT_SYMBOL_GPL(usb_sg_wait);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574
575/**
576 * usb_sg_cancel - stop scatter/gather i/o issued by usb_sg_wait()
577 * @io: request block, initialized with usb_sg_init()
578 *
579 * This stops a request after it has been started by usb_sg_wait().
580 * It can also prevents one initialized by usb_sg_init() from starting,
581 * so that call just frees resources allocated to the request.
582 */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800583void usb_sg_cancel(struct usb_sg_request *io)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584{
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800585 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800587 spin_lock_irqsave(&io->lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588
589 /* shut everything down, if it didn't already */
590 if (!io->status) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800591 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592
593 io->status = -ECONNRESET;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800594 spin_unlock(&io->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595 for (i = 0; i < io->entries; i++) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800596 int retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597
598 if (!io->urbs [i]->dev)
599 continue;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800600 retval = usb_unlink_urb(io->urbs [i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 if (retval != -EINPROGRESS && retval != -EBUSY)
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800602 dev_warn(&io->dev->dev, "%s, unlink --> %d\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 __FUNCTION__, retval);
604 }
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800605 spin_lock(&io->lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 }
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800607 spin_unlock_irqrestore(&io->lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600609EXPORT_SYMBOL_GPL(usb_sg_cancel);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610
611/*-------------------------------------------------------------------*/
612
613/**
614 * usb_get_descriptor - issues a generic GET_DESCRIPTOR request
615 * @dev: the device whose descriptor is being retrieved
616 * @type: the descriptor type (USB_DT_*)
617 * @index: the number of the descriptor
618 * @buf: where to put the descriptor
619 * @size: how big is "buf"?
620 * Context: !in_interrupt ()
621 *
622 * Gets a USB descriptor. Convenience functions exist to simplify
623 * getting some types of descriptors. Use
624 * usb_get_string() or usb_string() for USB_DT_STRING.
625 * Device (USB_DT_DEVICE) and configuration descriptors (USB_DT_CONFIG)
626 * are part of the device structure.
627 * In addition to a number of USB-standard descriptors, some
628 * devices also use class-specific or vendor-specific descriptors.
629 *
630 * This call is synchronous, and may not be used in an interrupt context.
631 *
632 * Returns the number of bytes received on success, or else the status code
633 * returned by the underlying usb_control_msg() call.
634 */
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800635int usb_get_descriptor(struct usb_device *dev, unsigned char type,
636 unsigned char index, void *buf, int size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637{
638 int i;
639 int result;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800640
641 memset(buf, 0, size); /* Make sure we parse really received data */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642
643 for (i = 0; i < 3; ++i) {
Alan Sternc39772d2007-08-20 10:45:28 -0400644 /* retry on length 0 or error; some devices are flakey */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645 result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
646 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
647 (type << 8) + index, 0, buf, size,
648 USB_CTRL_GET_TIMEOUT);
Alan Sternc39772d2007-08-20 10:45:28 -0400649 if (result <= 0 && result != -ETIMEDOUT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650 continue;
651 if (result > 1 && ((u8 *)buf)[1] != type) {
652 result = -EPROTO;
653 continue;
654 }
655 break;
656 }
657 return result;
658}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600659EXPORT_SYMBOL_GPL(usb_get_descriptor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660
661/**
662 * usb_get_string - gets a string descriptor
663 * @dev: the device whose string descriptor is being retrieved
664 * @langid: code for language chosen (from string descriptor zero)
665 * @index: the number of the descriptor
666 * @buf: where to put the string
667 * @size: how big is "buf"?
668 * Context: !in_interrupt ()
669 *
670 * Retrieves a string, encoded using UTF-16LE (Unicode, 16 bits per character,
671 * in little-endian byte order).
672 * The usb_string() function will often be a convenient way to turn
673 * these strings into kernel-printable form.
674 *
675 * Strings may be referenced in device, configuration, interface, or other
676 * descriptors, and could also be used in vendor-specific ways.
677 *
678 * This call is synchronous, and may not be used in an interrupt context.
679 *
680 * Returns the number of bytes received on success, or else the status code
681 * returned by the underlying usb_control_msg() call.
682 */
Adrian Bunke266a122005-11-08 21:05:43 +0100683static int usb_get_string(struct usb_device *dev, unsigned short langid,
684 unsigned char index, void *buf, int size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700685{
686 int i;
687 int result;
688
689 for (i = 0; i < 3; ++i) {
690 /* retry on length 0 or stall; some devices are flakey */
691 result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
692 USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
693 (USB_DT_STRING << 8) + index, langid, buf, size,
694 USB_CTRL_GET_TIMEOUT);
695 if (!(result == 0 || result == -EPIPE))
696 break;
697 }
698 return result;
699}
700
701static void usb_try_string_workarounds(unsigned char *buf, int *length)
702{
703 int newlength, oldlength = *length;
704
705 for (newlength = 2; newlength + 1 < oldlength; newlength += 2)
706 if (!isprint(buf[newlength]) || buf[newlength + 1])
707 break;
708
709 if (newlength > 2) {
710 buf[0] = newlength;
711 *length = newlength;
712 }
713}
714
715static int usb_string_sub(struct usb_device *dev, unsigned int langid,
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800716 unsigned int index, unsigned char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717{
718 int rc;
719
720 /* Try to read the string descriptor by asking for the maximum
721 * possible number of bytes */
Oliver Neukum7ceec1f2007-01-26 14:26:21 +0100722 if (dev->quirks & USB_QUIRK_STRING_FETCH_255)
723 rc = -EIO;
724 else
725 rc = usb_get_string(dev, langid, index, buf, 255);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726
727 /* If that failed try to read the descriptor length, then
728 * ask for just that many bytes */
729 if (rc < 2) {
730 rc = usb_get_string(dev, langid, index, buf, 2);
731 if (rc == 2)
732 rc = usb_get_string(dev, langid, index, buf, buf[0]);
733 }
734
735 if (rc >= 2) {
736 if (!buf[0] && !buf[1])
737 usb_try_string_workarounds(buf, &rc);
738
739 /* There might be extra junk at the end of the descriptor */
740 if (buf[0] < rc)
741 rc = buf[0];
742
743 rc = rc - (rc & 1); /* force a multiple of two */
744 }
745
746 if (rc < 2)
747 rc = (rc < 0 ? rc : -EINVAL);
748
749 return rc;
750}
751
752/**
753 * usb_string - returns ISO 8859-1 version of a string descriptor
754 * @dev: the device whose string descriptor is being retrieved
755 * @index: the number of the descriptor
756 * @buf: where to put the string
757 * @size: how big is "buf"?
758 * Context: !in_interrupt ()
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800759 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700760 * This converts the UTF-16LE encoded strings returned by devices, from
761 * usb_get_string_descriptor(), to null-terminated ISO-8859-1 encoded ones
762 * that are more usable in most kernel contexts. Note that all characters
763 * in the chosen descriptor that can't be encoded using ISO-8859-1
764 * are converted to the question mark ("?") character, and this function
765 * chooses strings in the first language supported by the device.
766 *
767 * The ASCII (or, redundantly, "US-ASCII") character set is the seven-bit
768 * subset of ISO 8859-1. ISO-8859-1 is the eight-bit subset of Unicode,
769 * and is appropriate for use many uses of English and several other
770 * Western European languages. (But it doesn't include the "Euro" symbol.)
771 *
772 * This call is synchronous, and may not be used in an interrupt context.
773 *
774 * Returns length of the string (>= 0) or usb_control_msg status (< 0).
775 */
776int usb_string(struct usb_device *dev, int index, char *buf, size_t size)
777{
778 unsigned char *tbuf;
779 int err;
780 unsigned int u, idx;
781
782 if (dev->state == USB_STATE_SUSPENDED)
783 return -EHOSTUNREACH;
784 if (size <= 0 || !buf || !index)
785 return -EINVAL;
786 buf[0] = 0;
787 tbuf = kmalloc(256, GFP_KERNEL);
788 if (!tbuf)
789 return -ENOMEM;
790
791 /* get langid for strings if it's not yet known */
792 if (!dev->have_langid) {
793 err = usb_string_sub(dev, 0, 0, tbuf);
794 if (err < 0) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800795 dev_err(&dev->dev,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 "string descriptor 0 read error: %d\n",
797 err);
798 goto errout;
799 } else if (err < 4) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800800 dev_err(&dev->dev, "string descriptor 0 too short\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801 err = -EINVAL;
802 goto errout;
803 } else {
Alan Sternce361582006-11-20 11:12:22 -0500804 dev->have_langid = 1;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800805 dev->string_langid = tbuf[2] | (tbuf[3] << 8);
806 /* always use the first langid listed */
807 dev_dbg(&dev->dev, "default language 0x%04x\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808 dev->string_langid);
809 }
810 }
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800811
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812 err = usb_string_sub(dev, dev->string_langid, index, tbuf);
813 if (err < 0)
814 goto errout;
815
816 size--; /* leave room for trailing NULL char in output buffer */
817 for (idx = 0, u = 2; u < err; u += 2) {
818 if (idx >= size)
819 break;
820 if (tbuf[u+1]) /* high byte */
821 buf[idx++] = '?'; /* non ISO-8859-1 character */
822 else
823 buf[idx++] = tbuf[u];
824 }
825 buf[idx] = 0;
826 err = idx;
827
828 if (tbuf[1] != USB_DT_STRING)
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800829 dev_dbg(&dev->dev,
830 "wrong descriptor type %02x for string %d (\"%s\")\n",
831 tbuf[1], index, buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832
833 errout:
834 kfree(tbuf);
835 return err;
836}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600837EXPORT_SYMBOL_GPL(usb_string);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838
Alan Stern4f62efe2005-10-24 16:24:14 -0400839/**
840 * usb_cache_string - read a string descriptor and cache it for later use
841 * @udev: the device whose string descriptor is being read
842 * @index: the descriptor index
843 *
844 * Returns a pointer to a kmalloc'ed buffer containing the descriptor string,
845 * or NULL if the index is 0 or the string could not be read.
846 */
847char *usb_cache_string(struct usb_device *udev, int index)
848{
849 char *buf;
850 char *smallbuf = NULL;
851 int len;
852
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800853 if (index <= 0)
854 return NULL;
855
856 buf = kmalloc(256, GFP_KERNEL);
857 if (buf) {
858 len = usb_string(udev, index, buf, 256);
859 if (len > 0) {
860 smallbuf = kmalloc(++len, GFP_KERNEL);
861 if (!smallbuf)
Alan Stern4f62efe2005-10-24 16:24:14 -0400862 return buf;
863 memcpy(smallbuf, buf, len);
864 }
865 kfree(buf);
866 }
867 return smallbuf;
868}
869
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870/*
871 * usb_get_device_descriptor - (re)reads the device descriptor (usbcore)
872 * @dev: the device whose device descriptor is being updated
873 * @size: how much of the descriptor to read
874 * Context: !in_interrupt ()
875 *
876 * Updates the copy of the device descriptor stored in the device structure,
Laurent Pinchart6ab16a92006-11-07 10:16:25 +0100877 * which dedicates space for this purpose.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700878 *
879 * Not exported, only for use by the core. If drivers really want to read
880 * the device descriptor directly, they can call usb_get_descriptor() with
881 * type = USB_DT_DEVICE and index = 0.
882 *
883 * This call is synchronous, and may not be used in an interrupt context.
884 *
885 * Returns the number of bytes received on success, or else the status code
886 * returned by the underlying usb_control_msg() call.
887 */
888int usb_get_device_descriptor(struct usb_device *dev, unsigned int size)
889{
890 struct usb_device_descriptor *desc;
891 int ret;
892
893 if (size > sizeof(*desc))
894 return -EINVAL;
895 desc = kmalloc(sizeof(*desc), GFP_NOIO);
896 if (!desc)
897 return -ENOMEM;
898
899 ret = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, size);
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800900 if (ret >= 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901 memcpy(&dev->descriptor, desc, size);
902 kfree(desc);
903 return ret;
904}
905
906/**
907 * usb_get_status - issues a GET_STATUS call
908 * @dev: the device whose status is being checked
909 * @type: USB_RECIP_*; for device, interface, or endpoint
910 * @target: zero (for device), else interface or endpoint number
911 * @data: pointer to two bytes of bitmap data
912 * Context: !in_interrupt ()
913 *
914 * Returns device, interface, or endpoint status. Normally only of
915 * interest to see if the device is self powered, or has enabled the
916 * remote wakeup facility; or whether a bulk or interrupt endpoint
917 * is halted ("stalled").
918 *
919 * Bits in these status bitmaps are set using the SET_FEATURE request,
920 * and cleared using the CLEAR_FEATURE request. The usb_clear_halt()
921 * function should be used to clear halt ("stall") status.
922 *
923 * This call is synchronous, and may not be used in an interrupt context.
924 *
925 * Returns the number of bytes received on success, or else the status code
926 * returned by the underlying usb_control_msg() call.
927 */
928int usb_get_status(struct usb_device *dev, int type, int target, void *data)
929{
930 int ret;
931 u16 *status = kmalloc(sizeof(*status), GFP_KERNEL);
932
933 if (!status)
934 return -ENOMEM;
935
936 ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
937 USB_REQ_GET_STATUS, USB_DIR_IN | type, 0, target, status,
938 sizeof(*status), USB_CTRL_GET_TIMEOUT);
939
940 *(u16 *)data = *status;
941 kfree(status);
942 return ret;
943}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -0600944EXPORT_SYMBOL_GPL(usb_get_status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945
946/**
947 * usb_clear_halt - tells device to clear endpoint halt/stall condition
948 * @dev: device whose endpoint is halted
949 * @pipe: endpoint "pipe" being cleared
950 * Context: !in_interrupt ()
951 *
952 * This is used to clear halt conditions for bulk and interrupt endpoints,
953 * as reported by URB completion status. Endpoints that are halted are
954 * sometimes referred to as being "stalled". Such endpoints are unable
955 * to transmit or receive data until the halt status is cleared. Any URBs
956 * queued for such an endpoint should normally be unlinked by the driver
957 * before clearing the halt condition, as described in sections 5.7.5
958 * and 5.8.5 of the USB 2.0 spec.
959 *
960 * Note that control and isochronous endpoints don't halt, although control
961 * endpoints report "protocol stall" (for unsupported requests) using the
962 * same status code used to report a true stall.
963 *
964 * This call is synchronous, and may not be used in an interrupt context.
965 *
966 * Returns zero on success, or else the status code returned by the
967 * underlying usb_control_msg() call.
968 */
969int usb_clear_halt(struct usb_device *dev, int pipe)
970{
971 int result;
972 int endp = usb_pipeendpoint(pipe);
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -0800973
974 if (usb_pipein(pipe))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975 endp |= USB_DIR_IN;
976
977 /* we don't care if it wasn't halted first. in fact some devices
978 * (like some ibmcam model 1 units) seem to expect hosts to make
979 * this request for iso endpoints, which can't halt!
980 */
981 result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
982 USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT,
983 USB_ENDPOINT_HALT, endp, NULL, 0,
984 USB_CTRL_SET_TIMEOUT);
985
986 /* don't un-halt or force to DATA0 except on success */
987 if (result < 0)
988 return result;
989
990 /* NOTE: seems like Microsoft and Apple don't bother verifying
991 * the clear "took", so some devices could lock up if you check...
992 * such as the Hagiwara FlashGate DUAL. So we won't bother.
993 *
994 * NOTE: make sure the logic here doesn't diverge much from
995 * the copy in usb-storage, for as long as we need two copies.
996 */
997
998 /* toggle was reset by the clear */
999 usb_settoggle(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe), 0);
1000
1001 return 0;
1002}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -06001003EXPORT_SYMBOL_GPL(usb_clear_halt);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004
1005/**
1006 * usb_disable_endpoint -- Disable an endpoint by address
1007 * @dev: the device whose endpoint is being disabled
1008 * @epaddr: the endpoint's address. Endpoint number for output,
1009 * endpoint number + USB_DIR_IN for input
1010 *
1011 * Deallocates hcd/hardware state for this endpoint ... and nukes all
1012 * pending urbs.
1013 *
1014 * If the HCD hasn't registered a disable() function, this sets the
1015 * endpoint's maxpacket size to 0 to prevent further submissions.
1016 */
1017void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr)
1018{
1019 unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK;
1020 struct usb_host_endpoint *ep;
1021
1022 if (!dev)
1023 return;
1024
1025 if (usb_endpoint_out(epaddr)) {
1026 ep = dev->ep_out[epnum];
1027 dev->ep_out[epnum] = NULL;
1028 } else {
1029 ep = dev->ep_in[epnum];
1030 dev->ep_in[epnum] = NULL;
1031 }
Alan Sternbdd016b2007-07-30 17:05:22 -04001032 if (ep) {
1033 ep->enabled = 0;
Alan Stern95cf82f2007-09-10 11:33:05 -04001034 usb_hcd_flush_endpoint(dev, ep);
1035 usb_hcd_disable_endpoint(dev, ep);
Alan Sternbdd016b2007-07-30 17:05:22 -04001036 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001037}
1038
1039/**
1040 * usb_disable_interface -- Disable all endpoints for an interface
1041 * @dev: the device whose interface is being disabled
1042 * @intf: pointer to the interface descriptor
1043 *
1044 * Disables all the endpoints for the interface's current altsetting.
1045 */
1046void usb_disable_interface(struct usb_device *dev, struct usb_interface *intf)
1047{
1048 struct usb_host_interface *alt = intf->cur_altsetting;
1049 int i;
1050
1051 for (i = 0; i < alt->desc.bNumEndpoints; ++i) {
1052 usb_disable_endpoint(dev,
1053 alt->endpoint[i].desc.bEndpointAddress);
1054 }
1055}
1056
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001057/**
Linus Torvalds1da177e2005-04-16 15:20:36 -07001058 * usb_disable_device - Disable all the endpoints for a USB device
1059 * @dev: the device whose endpoints are being disabled
1060 * @skip_ep0: 0 to disable endpoint 0, 1 to skip it.
1061 *
1062 * Disables all the device's endpoints, potentially including endpoint 0.
1063 * Deallocates hcd/hardware state for the endpoints (nuking all or most
1064 * pending urbs) and usbcore state for the interfaces, so that usbcore
1065 * must usb_set_configuration() before any interfaces could be used.
1066 */
1067void usb_disable_device(struct usb_device *dev, int skip_ep0)
1068{
1069 int i;
1070
1071 dev_dbg(&dev->dev, "%s nuking %s URBs\n", __FUNCTION__,
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001072 skip_ep0 ? "non-ep0" : "all");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001073 for (i = skip_ep0; i < 16; ++i) {
1074 usb_disable_endpoint(dev, i);
1075 usb_disable_endpoint(dev, i + USB_DIR_IN);
1076 }
1077 dev->toggle[0] = dev->toggle[1] = 0;
1078
1079 /* getting rid of interfaces will disconnect
1080 * any drivers bound to them (a key side effect)
1081 */
1082 if (dev->actconfig) {
1083 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
1084 struct usb_interface *interface;
1085
Alan Stern86d30742005-07-29 12:17:16 -07001086 /* remove this interface if it has been registered */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001087 interface = dev->actconfig->interface[i];
Daniel Ritzd305ef52005-09-22 00:47:24 -07001088 if (!device_is_registered(&interface->dev))
Alan Stern86d30742005-07-29 12:17:16 -07001089 continue;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001090 dev_dbg(&dev->dev, "unregistering interface %s\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001091 interface->dev.bus_id);
1092 usb_remove_sysfs_intf_files(interface);
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001093 device_del(&interface->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001094 }
1095
1096 /* Now that the interfaces are unbound, nobody should
1097 * try to access them.
1098 */
1099 for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001100 put_device(&dev->actconfig->interface[i]->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001101 dev->actconfig->interface[i] = NULL;
1102 }
1103 dev->actconfig = NULL;
1104 if (dev->state == USB_STATE_CONFIGURED)
1105 usb_set_device_state(dev, USB_STATE_ADDRESS);
1106 }
1107}
1108
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001109/**
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 * usb_enable_endpoint - Enable an endpoint for USB communications
1111 * @dev: the device whose interface is being enabled
1112 * @ep: the endpoint
1113 *
1114 * Resets the endpoint toggle, and sets dev->ep_{in,out} pointers.
1115 * For control endpoints, both the input and output sides are handled.
1116 */
Alan Sternbdd016b2007-07-30 17:05:22 -04001117void usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001118{
Alan Sternbdd016b2007-07-30 17:05:22 -04001119 int epnum = usb_endpoint_num(&ep->desc);
1120 int is_out = usb_endpoint_dir_out(&ep->desc);
1121 int is_control = usb_endpoint_xfer_control(&ep->desc);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001122
Alan Sternbdd016b2007-07-30 17:05:22 -04001123 if (is_out || is_control) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001124 usb_settoggle(dev, epnum, 1, 0);
1125 dev->ep_out[epnum] = ep;
1126 }
Alan Sternbdd016b2007-07-30 17:05:22 -04001127 if (!is_out || is_control) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001128 usb_settoggle(dev, epnum, 0, 0);
1129 dev->ep_in[epnum] = ep;
1130 }
Alan Sternbdd016b2007-07-30 17:05:22 -04001131 ep->enabled = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001132}
1133
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001134/**
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135 * usb_enable_interface - Enable all the endpoints for an interface
1136 * @dev: the device whose interface is being enabled
1137 * @intf: pointer to the interface descriptor
1138 *
1139 * Enables all the endpoints for the interface's current altsetting.
1140 */
1141static void usb_enable_interface(struct usb_device *dev,
1142 struct usb_interface *intf)
1143{
1144 struct usb_host_interface *alt = intf->cur_altsetting;
1145 int i;
1146
1147 for (i = 0; i < alt->desc.bNumEndpoints; ++i)
1148 usb_enable_endpoint(dev, &alt->endpoint[i]);
1149}
1150
1151/**
1152 * usb_set_interface - Makes a particular alternate setting be current
1153 * @dev: the device whose interface is being updated
1154 * @interface: the interface being updated
1155 * @alternate: the setting being chosen.
1156 * Context: !in_interrupt ()
1157 *
1158 * This is used to enable data transfers on interfaces that may not
1159 * be enabled by default. Not all devices support such configurability.
1160 * Only the driver bound to an interface may change its setting.
1161 *
1162 * Within any given configuration, each interface may have several
1163 * alternative settings. These are often used to control levels of
1164 * bandwidth consumption. For example, the default setting for a high
1165 * speed interrupt endpoint may not send more than 64 bytes per microframe,
1166 * while interrupt transfers of up to 3KBytes per microframe are legal.
1167 * Also, isochronous endpoints may never be part of an
1168 * interface's default setting. To access such bandwidth, alternate
1169 * interface settings must be made current.
1170 *
1171 * Note that in the Linux USB subsystem, bandwidth associated with
1172 * an endpoint in a given alternate setting is not reserved until an URB
1173 * is submitted that needs that bandwidth. Some other operating systems
1174 * allocate bandwidth early, when a configuration is chosen.
1175 *
1176 * This call is synchronous, and may not be used in an interrupt context.
1177 * Also, drivers must not change altsettings while urbs are scheduled for
1178 * endpoints in that interface; all such urbs must first be completed
1179 * (perhaps forced by unlinking).
1180 *
1181 * Returns zero on success, or else the status code returned by the
1182 * underlying usb_control_msg() call.
1183 */
1184int usb_set_interface(struct usb_device *dev, int interface, int alternate)
1185{
1186 struct usb_interface *iface;
1187 struct usb_host_interface *alt;
1188 int ret;
1189 int manual = 0;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001190 unsigned int epaddr;
1191 unsigned int pipe;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001192
1193 if (dev->state == USB_STATE_SUSPENDED)
1194 return -EHOSTUNREACH;
1195
1196 iface = usb_ifnum_to_if(dev, interface);
1197 if (!iface) {
1198 dev_dbg(&dev->dev, "selecting invalid interface %d\n",
1199 interface);
1200 return -EINVAL;
1201 }
1202
1203 alt = usb_altnum_to_altsetting(iface, alternate);
1204 if (!alt) {
1205 warn("selecting invalid altsetting %d", alternate);
1206 return -EINVAL;
1207 }
1208
1209 ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1210 USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE,
1211 alternate, interface, NULL, 0, 5000);
1212
1213 /* 9.4.10 says devices don't need this and are free to STALL the
1214 * request if the interface only has one alternate setting.
1215 */
1216 if (ret == -EPIPE && iface->num_altsetting == 1) {
1217 dev_dbg(&dev->dev,
1218 "manual set_interface for iface %d, alt %d\n",
1219 interface, alternate);
1220 manual = 1;
1221 } else if (ret < 0)
1222 return ret;
1223
1224 /* FIXME drivers shouldn't need to replicate/bugfix the logic here
1225 * when they implement async or easily-killable versions of this or
1226 * other "should-be-internal" functions (like clear_halt).
1227 * should hcd+usbcore postprocess control requests?
1228 */
1229
1230 /* prevent submissions using previous endpoint settings */
Alan Stern7e615592007-11-06 11:43:42 -05001231 if (iface->cur_altsetting != alt && device_is_registered(&iface->dev))
Alan Stern0e6c8e82005-10-24 15:33:03 -04001232 usb_remove_sysfs_intf_files(iface);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001233 usb_disable_interface(dev, iface);
1234
Linus Torvalds1da177e2005-04-16 15:20:36 -07001235 iface->cur_altsetting = alt;
1236
1237 /* If the interface only has one altsetting and the device didn't
David Brownella81e7ec2005-04-18 17:39:25 -07001238 * accept the request, we attempt to carry out the equivalent action
Linus Torvalds1da177e2005-04-16 15:20:36 -07001239 * by manually clearing the HALT feature for each endpoint in the
1240 * new altsetting.
1241 */
1242 if (manual) {
1243 int i;
1244
1245 for (i = 0; i < alt->desc.bNumEndpoints; i++) {
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001246 epaddr = alt->endpoint[i].desc.bEndpointAddress;
1247 pipe = __create_pipe(dev,
1248 USB_ENDPOINT_NUMBER_MASK & epaddr) |
1249 (usb_endpoint_out(epaddr) ?
1250 USB_DIR_OUT : USB_DIR_IN);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001251
1252 usb_clear_halt(dev, pipe);
1253 }
1254 }
1255
1256 /* 9.1.1.5: reset toggles for all endpoints in the new altsetting
1257 *
1258 * Note:
1259 * Despite EP0 is always present in all interfaces/AS, the list of
1260 * endpoints from the descriptor does not contain EP0. Due to its
1261 * omnipresence one might expect EP0 being considered "affected" by
1262 * any SetInterface request and hence assume toggles need to be reset.
1263 * However, EP0 toggles are re-synced for every individual transfer
1264 * during the SETUP stage - hence EP0 toggles are "don't care" here.
1265 * (Likewise, EP0 never "halts" on well designed devices.)
1266 */
1267 usb_enable_interface(dev, iface);
Alan Stern7e615592007-11-06 11:43:42 -05001268 if (device_is_registered(&iface->dev))
Alan Stern0e6c8e82005-10-24 15:33:03 -04001269 usb_create_sysfs_intf_files(iface);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001270
1271 return 0;
1272}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -06001273EXPORT_SYMBOL_GPL(usb_set_interface);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001274
1275/**
1276 * usb_reset_configuration - lightweight device reset
1277 * @dev: the device whose configuration is being reset
1278 *
1279 * This issues a standard SET_CONFIGURATION request to the device using
1280 * the current configuration. The effect is to reset most USB-related
1281 * state in the device, including interface altsettings (reset to zero),
1282 * endpoint halts (cleared), and data toggle (only for bulk and interrupt
1283 * endpoints). Other usbcore state is unchanged, including bindings of
1284 * usb device drivers to interfaces.
1285 *
1286 * Because this affects multiple interfaces, avoid using this with composite
1287 * (multi-interface) devices. Instead, the driver for each interface may
David Brownella81e7ec2005-04-18 17:39:25 -07001288 * use usb_set_interface() on the interfaces it claims. Be careful though;
1289 * some devices don't support the SET_INTERFACE request, and others won't
1290 * reset all the interface state (notably data toggles). Resetting the whole
Linus Torvalds1da177e2005-04-16 15:20:36 -07001291 * configuration would affect other drivers' interfaces.
1292 *
1293 * The caller must own the device lock.
1294 *
1295 * Returns zero on success, else a negative error code.
1296 */
1297int usb_reset_configuration(struct usb_device *dev)
1298{
1299 int i, retval;
1300 struct usb_host_config *config;
1301
1302 if (dev->state == USB_STATE_SUSPENDED)
1303 return -EHOSTUNREACH;
1304
1305 /* caller must have locked the device and must own
1306 * the usb bus readlock (so driver bindings are stable);
1307 * calls during probe() are fine
1308 */
1309
1310 for (i = 1; i < 16; ++i) {
1311 usb_disable_endpoint(dev, i);
1312 usb_disable_endpoint(dev, i + USB_DIR_IN);
1313 }
1314
1315 config = dev->actconfig;
1316 retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1317 USB_REQ_SET_CONFIGURATION, 0,
1318 config->desc.bConfigurationValue, 0,
1319 NULL, 0, USB_CTRL_SET_TIMEOUT);
Alan Stern0e6c8e82005-10-24 15:33:03 -04001320 if (retval < 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001321 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322
1323 dev->toggle[0] = dev->toggle[1] = 0;
1324
1325 /* re-init hc/hcd interface/endpoint state */
1326 for (i = 0; i < config->desc.bNumInterfaces; i++) {
1327 struct usb_interface *intf = config->interface[i];
1328 struct usb_host_interface *alt;
1329
Alan Stern0e6c8e82005-10-24 15:33:03 -04001330 if (device_is_registered(&intf->dev))
1331 usb_remove_sysfs_intf_files(intf);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001332 alt = usb_altnum_to_altsetting(intf, 0);
1333
1334 /* No altsetting 0? We'll assume the first altsetting.
1335 * We could use a GetInterface call, but if a device is
1336 * so non-compliant that it doesn't have altsetting 0
1337 * then I wouldn't trust its reply anyway.
1338 */
1339 if (!alt)
1340 alt = &intf->altsetting[0];
1341
1342 intf->cur_altsetting = alt;
1343 usb_enable_interface(dev, intf);
Alan Stern0e6c8e82005-10-24 15:33:03 -04001344 if (device_is_registered(&intf->dev))
1345 usb_create_sysfs_intf_files(intf);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346 }
1347 return 0;
1348}
Greg Kroah-Hartman782e70c2008-01-25 11:12:21 -06001349EXPORT_SYMBOL_GPL(usb_reset_configuration);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350
Greg Kroah-Hartmanb0e396e2007-08-02 22:44:27 -06001351static void usb_release_interface(struct device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001352{
1353 struct usb_interface *intf = to_usb_interface(dev);
1354 struct usb_interface_cache *intfc =
1355 altsetting_to_usb_interface_cache(intf->altsetting);
1356
1357 kref_put(&intfc->ref, usb_release_interface_cache);
1358 kfree(intf);
1359}
1360
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001361#ifdef CONFIG_HOTPLUG
Kay Sievers7eff2e72007-08-14 15:15:12 +02001362static int usb_if_uevent(struct device *dev, struct kobj_uevent_env *env)
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001363{
1364 struct usb_device *usb_dev;
1365 struct usb_interface *intf;
1366 struct usb_host_interface *alt;
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001367
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001368 intf = to_usb_interface(dev);
1369 usb_dev = interface_to_usbdev(intf);
1370 alt = intf->cur_altsetting;
1371
Kay Sievers7eff2e72007-08-14 15:15:12 +02001372 if (add_uevent_var(env, "INTERFACE=%d/%d/%d",
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001373 alt->desc.bInterfaceClass,
1374 alt->desc.bInterfaceSubClass,
1375 alt->desc.bInterfaceProtocol))
1376 return -ENOMEM;
1377
Kay Sievers7eff2e72007-08-14 15:15:12 +02001378 if (add_uevent_var(env,
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001379 "MODALIAS=usb:"
1380 "v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02X",
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001381 le16_to_cpu(usb_dev->descriptor.idVendor),
1382 le16_to_cpu(usb_dev->descriptor.idProduct),
1383 le16_to_cpu(usb_dev->descriptor.bcdDevice),
1384 usb_dev->descriptor.bDeviceClass,
1385 usb_dev->descriptor.bDeviceSubClass,
1386 usb_dev->descriptor.bDeviceProtocol,
1387 alt->desc.bInterfaceClass,
1388 alt->desc.bInterfaceSubClass,
1389 alt->desc.bInterfaceProtocol))
1390 return -ENOMEM;
1391
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001392 return 0;
1393}
1394
1395#else
1396
Kay Sievers7eff2e72007-08-14 15:15:12 +02001397static int usb_if_uevent(struct device *dev, struct kobj_uevent_env *env)
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001398{
1399 return -ENODEV;
1400}
1401#endif /* CONFIG_HOTPLUG */
1402
1403struct device_type usb_if_device_type = {
1404 .name = "usb_interface",
1405 .release = usb_release_interface,
1406 .uevent = usb_if_uevent,
1407};
1408
Craig W. Nadler165fe972007-06-15 23:14:35 -04001409static struct usb_interface_assoc_descriptor *find_iad(struct usb_device *dev,
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001410 struct usb_host_config *config,
1411 u8 inum)
Craig W. Nadler165fe972007-06-15 23:14:35 -04001412{
1413 struct usb_interface_assoc_descriptor *retval = NULL;
1414 struct usb_interface_assoc_descriptor *intf_assoc;
1415 int first_intf;
1416 int last_intf;
1417 int i;
1418
1419 for (i = 0; (i < USB_MAXIADS && config->intf_assoc[i]); i++) {
1420 intf_assoc = config->intf_assoc[i];
1421 if (intf_assoc->bInterfaceCount == 0)
1422 continue;
1423
1424 first_intf = intf_assoc->bFirstInterface;
1425 last_intf = first_intf + (intf_assoc->bInterfaceCount - 1);
1426 if (inum >= first_intf && inum <= last_intf) {
1427 if (!retval)
1428 retval = intf_assoc;
1429 else
1430 dev_err(&dev->dev, "Interface #%d referenced"
1431 " by multiple IADs\n", inum);
1432 }
1433 }
1434
1435 return retval;
1436}
1437
Linus Torvalds1da177e2005-04-16 15:20:36 -07001438/*
1439 * usb_set_configuration - Makes a particular device setting be current
1440 * @dev: the device whose configuration is being updated
1441 * @configuration: the configuration being chosen.
1442 * Context: !in_interrupt(), caller owns the device lock
1443 *
1444 * This is used to enable non-default device modes. Not all devices
1445 * use this kind of configurability; many devices only have one
1446 * configuration.
1447 *
Alan Stern3f141e22007-02-08 16:40:43 -05001448 * @configuration is the value of the configuration to be installed.
1449 * According to the USB spec (e.g. section 9.1.1.5), configuration values
1450 * must be non-zero; a value of zero indicates that the device in
1451 * unconfigured. However some devices erroneously use 0 as one of their
1452 * configuration values. To help manage such devices, this routine will
1453 * accept @configuration = -1 as indicating the device should be put in
1454 * an unconfigured state.
1455 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001456 * USB device configurations may affect Linux interoperability,
1457 * power consumption and the functionality available. For example,
1458 * the default configuration is limited to using 100mA of bus power,
1459 * so that when certain device functionality requires more power,
1460 * and the device is bus powered, that functionality should be in some
1461 * non-default device configuration. Other device modes may also be
1462 * reflected as configuration options, such as whether two ISDN
1463 * channels are available independently; and choosing between open
1464 * standard device protocols (like CDC) or proprietary ones.
1465 *
Inaky Perez-Gonzalez16bbab22007-07-31 20:34:01 -07001466 * Note that a non-authorized device (dev->authorized == 0) will only
1467 * be put in unconfigured mode.
1468 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001469 * Note that USB has an additional level of device configurability,
1470 * associated with interfaces. That configurability is accessed using
1471 * usb_set_interface().
1472 *
1473 * This call is synchronous. The calling context must be able to sleep,
1474 * must own the device lock, and must not hold the driver model's USB
Greg Kroah-Hartman341487a82007-04-09 11:52:31 -04001475 * bus mutex; usb device driver probe() methods cannot use this routine.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001476 *
1477 * Returns zero on success, or else the status code returned by the
Steven Cole093cf722005-05-03 19:07:24 -06001478 * underlying call that failed. On successful completion, each interface
Linus Torvalds1da177e2005-04-16 15:20:36 -07001479 * in the original device configuration has been destroyed, and each one
1480 * in the new configuration has been probed by all relevant usb device
1481 * drivers currently known to the kernel.
1482 */
1483int usb_set_configuration(struct usb_device *dev, int configuration)
1484{
1485 int i, ret;
1486 struct usb_host_config *cp = NULL;
1487 struct usb_interface **new_interfaces = NULL;
1488 int n, nintf;
1489
Inaky Perez-Gonzalez16bbab22007-07-31 20:34:01 -07001490 if (dev->authorized == 0 || configuration == -1)
Alan Stern3f141e22007-02-08 16:40:43 -05001491 configuration = 0;
1492 else {
1493 for (i = 0; i < dev->descriptor.bNumConfigurations; i++) {
1494 if (dev->config[i].desc.bConfigurationValue ==
1495 configuration) {
1496 cp = &dev->config[i];
1497 break;
1498 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001499 }
1500 }
1501 if ((!cp && configuration != 0))
1502 return -EINVAL;
1503
1504 /* The USB spec says configuration 0 means unconfigured.
1505 * But if a device includes a configuration numbered 0,
1506 * we will accept it as a correctly configured state.
Alan Stern3f141e22007-02-08 16:40:43 -05001507 * Use -1 if you really want to unconfigure the device.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001508 */
1509 if (cp && configuration == 0)
1510 dev_warn(&dev->dev, "config 0 descriptor??\n");
1511
Linus Torvalds1da177e2005-04-16 15:20:36 -07001512 /* Allocate memory for new interfaces before doing anything else,
1513 * so that if we run out then nothing will have changed. */
1514 n = nintf = 0;
1515 if (cp) {
1516 nintf = cp->desc.bNumInterfaces;
1517 new_interfaces = kmalloc(nintf * sizeof(*new_interfaces),
1518 GFP_KERNEL);
1519 if (!new_interfaces) {
Joe Perches898eb712007-10-18 03:06:30 -07001520 dev_err(&dev->dev, "Out of memory\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001521 return -ENOMEM;
1522 }
1523
1524 for (; n < nintf; ++n) {
Alan Stern0a1ef3b2005-10-24 15:38:24 -04001525 new_interfaces[n] = kzalloc(
Linus Torvalds1da177e2005-04-16 15:20:36 -07001526 sizeof(struct usb_interface),
1527 GFP_KERNEL);
1528 if (!new_interfaces[n]) {
Joe Perches898eb712007-10-18 03:06:30 -07001529 dev_err(&dev->dev, "Out of memory\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001530 ret = -ENOMEM;
1531free_interfaces:
1532 while (--n >= 0)
1533 kfree(new_interfaces[n]);
1534 kfree(new_interfaces);
1535 return ret;
1536 }
1537 }
Alan Stern6ad07122006-06-01 13:59:16 -04001538
1539 i = dev->bus_mA - cp->desc.bMaxPower * 2;
1540 if (i < 0)
1541 dev_warn(&dev->dev, "new config #%d exceeds power "
1542 "limit by %dmA\n",
1543 configuration, -i);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001544 }
1545
Alan Stern01d883d2006-08-30 15:47:18 -04001546 /* Wake up the device so we can send it the Set-Config request */
Alan Stern94fcda12006-11-20 11:38:46 -05001547 ret = usb_autoresume_device(dev);
Alan Stern01d883d2006-08-30 15:47:18 -04001548 if (ret)
1549 goto free_interfaces;
1550
Linus Torvalds1da177e2005-04-16 15:20:36 -07001551 /* if it's already configured, clear out old state first.
1552 * getting rid of old interfaces means unbinding their drivers.
1553 */
1554 if (dev->state != USB_STATE_ADDRESS)
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001555 usb_disable_device(dev, 1); /* Skip ep0 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001556
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001557 ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
1558 USB_REQ_SET_CONFIGURATION, 0, configuration, 0,
1559 NULL, 0, USB_CTRL_SET_TIMEOUT);
1560 if (ret < 0) {
Alan Stern6ad07122006-06-01 13:59:16 -04001561 /* All the old state is gone, so what else can we do?
1562 * The device is probably useless now anyway.
1563 */
1564 cp = NULL;
1565 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001566
1567 dev->actconfig = cp;
Alan Stern6ad07122006-06-01 13:59:16 -04001568 if (!cp) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001569 usb_set_device_state(dev, USB_STATE_ADDRESS);
Alan Stern94fcda12006-11-20 11:38:46 -05001570 usb_autosuspend_device(dev);
Alan Stern6ad07122006-06-01 13:59:16 -04001571 goto free_interfaces;
1572 }
1573 usb_set_device_state(dev, USB_STATE_CONFIGURED);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001574
Alan Stern6ad07122006-06-01 13:59:16 -04001575 /* Initialize the new interface structures and the
1576 * hc/hcd/usbcore interface/endpoint state.
1577 */
1578 for (i = 0; i < nintf; ++i) {
1579 struct usb_interface_cache *intfc;
1580 struct usb_interface *intf;
1581 struct usb_host_interface *alt;
1582
1583 cp->interface[i] = intf = new_interfaces[i];
1584 intfc = cp->intf_cache[i];
1585 intf->altsetting = intfc->altsetting;
1586 intf->num_altsetting = intfc->num_altsetting;
Craig W. Nadler165fe972007-06-15 23:14:35 -04001587 intf->intf_assoc = find_iad(dev, cp, i);
Alan Stern6ad07122006-06-01 13:59:16 -04001588 kref_get(&intfc->ref);
1589
1590 alt = usb_altnum_to_altsetting(intf, 0);
1591
1592 /* No altsetting 0? We'll assume the first altsetting.
1593 * We could use a GetInterface call, but if a device is
1594 * so non-compliant that it doesn't have altsetting 0
1595 * then I wouldn't trust its reply anyway.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001596 */
Alan Stern6ad07122006-06-01 13:59:16 -04001597 if (!alt)
1598 alt = &intf->altsetting[0];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001599
Alan Stern6ad07122006-06-01 13:59:16 -04001600 intf->cur_altsetting = alt;
1601 usb_enable_interface(dev, intf);
1602 intf->dev.parent = &dev->dev;
1603 intf->dev.driver = NULL;
1604 intf->dev.bus = &usb_bus_type;
Kay Sievers9f8b17e2007-03-13 15:59:31 +01001605 intf->dev.type = &usb_if_device_type;
Alan Stern6ad07122006-06-01 13:59:16 -04001606 intf->dev.dma_mask = dev->dev.dma_mask;
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001607 device_initialize(&intf->dev);
Alan Stern6ad07122006-06-01 13:59:16 -04001608 mark_quiesced(intf);
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001609 sprintf(&intf->dev.bus_id[0], "%d-%s:%d.%d",
1610 dev->bus->busnum, dev->devpath,
1611 configuration, alt->desc.bInterfaceNumber);
Alan Stern6ad07122006-06-01 13:59:16 -04001612 }
1613 kfree(new_interfaces);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001614
Alan Stern6ad07122006-06-01 13:59:16 -04001615 if (cp->string == NULL)
1616 cp->string = usb_cache_string(dev, cp->desc.iConfiguration);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001617
Alan Stern6ad07122006-06-01 13:59:16 -04001618 /* Now that all the interfaces are set up, register them
1619 * to trigger binding of drivers to interfaces. probe()
1620 * routines may install different altsettings and may
1621 * claim() any interfaces not yet bound. Many class drivers
1622 * need that: CDC, audio, video, etc.
1623 */
1624 for (i = 0; i < nintf; ++i) {
1625 struct usb_interface *intf = cp->interface[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -07001626
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001627 dev_dbg(&dev->dev,
Alan Stern6ad07122006-06-01 13:59:16 -04001628 "adding %s (config #%d, interface %d)\n",
1629 intf->dev.bus_id, configuration,
1630 intf->cur_altsetting->desc.bInterfaceNumber);
Greg Kroah-Hartman3e35bf32008-01-30 15:21:33 -08001631 ret = device_add(&intf->dev);
Alan Stern6ad07122006-06-01 13:59:16 -04001632 if (ret != 0) {
1633 dev_err(&dev->dev, "device_add(%s) --> %d\n",
1634 intf->dev.bus_id, ret);
1635 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001636 }
Alan Stern439a9032007-10-19 09:51:58 -04001637 usb_create_sysfs_intf_files(intf);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001638 }
1639
Alan Stern94fcda12006-11-20 11:38:46 -05001640 usb_autosuspend_device(dev);
Alan Stern86d30742005-07-29 12:17:16 -07001641 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001642}
1643
Alan Stern088dc272006-08-21 12:08:19 -04001644struct set_config_request {
1645 struct usb_device *udev;
1646 int config;
1647 struct work_struct work;
1648};
1649
1650/* Worker routine for usb_driver_set_configuration() */
David Howellsc4028952006-11-22 14:57:56 +00001651static void driver_set_config_work(struct work_struct *work)
Alan Stern088dc272006-08-21 12:08:19 -04001652{
David Howellsc4028952006-11-22 14:57:56 +00001653 struct set_config_request *req =
1654 container_of(work, struct set_config_request, work);
Alan Stern088dc272006-08-21 12:08:19 -04001655
1656 usb_lock_device(req->udev);
1657 usb_set_configuration(req->udev, req->config);
1658 usb_unlock_device(req->udev);
1659 usb_put_dev(req->udev);
1660 kfree(req);
1661}
1662
1663/**
1664 * usb_driver_set_configuration - Provide a way for drivers to change device configurations
1665 * @udev: the device whose configuration is being updated
1666 * @config: the configuration being chosen.
1667 * Context: In process context, must be able to sleep
1668 *
1669 * Device interface drivers are not allowed to change device configurations.
1670 * This is because changing configurations will destroy the interface the
1671 * driver is bound to and create new ones; it would be like a floppy-disk
1672 * driver telling the computer to replace the floppy-disk drive with a
1673 * tape drive!
1674 *
1675 * Still, in certain specialized circumstances the need may arise. This
1676 * routine gets around the normal restrictions by using a work thread to
1677 * submit the change-config request.
1678 *
1679 * Returns 0 if the request was succesfully queued, error code otherwise.
1680 * The caller has no way to know whether the queued request will eventually
1681 * succeed.
1682 */
1683int usb_driver_set_configuration(struct usb_device *udev, int config)
1684{
1685 struct set_config_request *req;
1686
1687 req = kmalloc(sizeof(*req), GFP_KERNEL);
1688 if (!req)
1689 return -ENOMEM;
1690 req->udev = udev;
1691 req->config = config;
David Howellsc4028952006-11-22 14:57:56 +00001692 INIT_WORK(&req->work, driver_set_config_work);
Alan Stern088dc272006-08-21 12:08:19 -04001693
1694 usb_get_dev(udev);
Alan Stern1737bf22006-12-15 16:04:52 -05001695 schedule_work(&req->work);
Alan Stern088dc272006-08-21 12:08:19 -04001696 return 0;
1697}
1698EXPORT_SYMBOL_GPL(usb_driver_set_configuration);