2 * uvc_video.c -- USB Video Class driver - Video handling
4 * Copyright (C) 2005-2009
5 * Laurent Pinchart (laurent.pinchart@skynet.be)
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
14 #include <linux/kernel.h>
15 #include <linux/list.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/usb.h>
19 #include <linux/videodev2.h>
20 #include <linux/vmalloc.h>
21 #include <linux/wait.h>
22 #include <asm/atomic.h>
23 #include <asm/unaligned.h>
25 #include <media/v4l2-common.h>
29 /* ------------------------------------------------------------------------
33 static int __uvc_query_ctrl(struct uvc_device
*dev
, __u8 query
, __u8 unit
,
34 __u8 intfnum
, __u8 cs
, void *data
, __u16 size
,
37 __u8 type
= USB_TYPE_CLASS
| USB_RECIP_INTERFACE
;
40 pipe
= (query
& 0x80) ? usb_rcvctrlpipe(dev
->udev
, 0)
41 : usb_sndctrlpipe(dev
->udev
, 0);
42 type
|= (query
& 0x80) ? USB_DIR_IN
: USB_DIR_OUT
;
44 return usb_control_msg(dev
->udev
, pipe
, query
, type
, cs
<< 8,
45 unit
<< 8 | intfnum
, data
, size
, timeout
);
48 int uvc_query_ctrl(struct uvc_device
*dev
, __u8 query
, __u8 unit
,
49 __u8 intfnum
, __u8 cs
, void *data
, __u16 size
)
53 ret
= __uvc_query_ctrl(dev
, query
, unit
, intfnum
, cs
, data
, size
,
54 UVC_CTRL_CONTROL_TIMEOUT
);
56 uvc_printk(KERN_ERR
, "Failed to query (%u) UVC control %u "
57 "(unit %u) : %d (exp. %u).\n", query
, cs
, unit
, ret
,
65 static void uvc_fixup_video_ctrl(struct uvc_streaming
*stream
,
66 struct uvc_streaming_control
*ctrl
)
68 struct uvc_format
*format
;
69 struct uvc_frame
*frame
= NULL
;
72 if (ctrl
->bFormatIndex
<= 0 ||
73 ctrl
->bFormatIndex
> stream
->nformats
)
76 format
= &stream
->format
[ctrl
->bFormatIndex
- 1];
78 for (i
= 0; i
< format
->nframes
; ++i
) {
79 if (format
->frame
[i
].bFrameIndex
== ctrl
->bFrameIndex
) {
80 frame
= &format
->frame
[i
];
88 if (!(format
->flags
& UVC_FMT_FLAG_COMPRESSED
) ||
89 (ctrl
->dwMaxVideoFrameSize
== 0 &&
90 stream
->dev
->uvc_version
< 0x0110))
91 ctrl
->dwMaxVideoFrameSize
=
92 frame
->dwMaxVideoFrameBufferSize
;
94 if (!(format
->flags
& UVC_FMT_FLAG_COMPRESSED
) &&
95 stream
->dev
->quirks
& UVC_QUIRK_FIX_BANDWIDTH
&&
96 stream
->intf
->num_altsetting
> 1) {
100 interval
= (ctrl
->dwFrameInterval
> 100000)
101 ? ctrl
->dwFrameInterval
102 : frame
->dwFrameInterval
[0];
104 /* Compute a bandwidth estimation by multiplying the frame
105 * size by the number of video frames per second, divide the
106 * result by the number of USB frames (or micro-frames for
107 * high-speed devices) per second and add the UVC header size
108 * (assumed to be 12 bytes long).
110 bandwidth
= frame
->wWidth
* frame
->wHeight
/ 8 * format
->bpp
;
111 bandwidth
*= 10000000 / interval
+ 1;
113 if (stream
->dev
->udev
->speed
== USB_SPEED_HIGH
)
117 ctrl
->dwMaxPayloadTransferSize
= bandwidth
;
121 static int uvc_get_video_ctrl(struct uvc_streaming
*stream
,
122 struct uvc_streaming_control
*ctrl
, int probe
, __u8 query
)
128 size
= stream
->dev
->uvc_version
>= 0x0110 ? 34 : 26;
129 if ((stream
->dev
->quirks
& UVC_QUIRK_PROBE_DEF
) &&
130 query
== UVC_GET_DEF
)
133 data
= kmalloc(size
, GFP_KERNEL
);
137 ret
= __uvc_query_ctrl(stream
->dev
, query
, 0, stream
->intfnum
,
138 probe
? UVC_VS_PROBE_CONTROL
: UVC_VS_COMMIT_CONTROL
, data
,
139 size
, uvc_timeout_param
);
141 if ((query
== UVC_GET_MIN
|| query
== UVC_GET_MAX
) && ret
== 2) {
142 /* Some cameras, mostly based on Bison Electronics chipsets,
143 * answer a GET_MIN or GET_MAX request with the wCompQuality
146 uvc_warn_once(stream
->dev
, UVC_WARN_MINMAX
, "UVC non "
147 "compliance - GET_MIN/MAX(PROBE) incorrectly "
148 "supported. Enabling workaround.\n");
149 memset(ctrl
, 0, sizeof *ctrl
);
150 ctrl
->wCompQuality
= le16_to_cpup((__le16
*)data
);
153 } else if (query
== UVC_GET_DEF
&& probe
== 1 && ret
!= size
) {
154 /* Many cameras don't support the GET_DEF request on their
155 * video probe control. Warn once and return, the caller will
156 * fall back to GET_CUR.
158 uvc_warn_once(stream
->dev
, UVC_WARN_PROBE_DEF
, "UVC non "
159 "compliance - GET_DEF(PROBE) not supported. "
160 "Enabling workaround.\n");
163 } else if (ret
!= size
) {
164 uvc_printk(KERN_ERR
, "Failed to query (%u) UVC %s control : "
165 "%d (exp. %u).\n", query
, probe
? "probe" : "commit",
171 ctrl
->bmHint
= le16_to_cpup((__le16
*)&data
[0]);
172 ctrl
->bFormatIndex
= data
[2];
173 ctrl
->bFrameIndex
= data
[3];
174 ctrl
->dwFrameInterval
= le32_to_cpup((__le32
*)&data
[4]);
175 ctrl
->wKeyFrameRate
= le16_to_cpup((__le16
*)&data
[8]);
176 ctrl
->wPFrameRate
= le16_to_cpup((__le16
*)&data
[10]);
177 ctrl
->wCompQuality
= le16_to_cpup((__le16
*)&data
[12]);
178 ctrl
->wCompWindowSize
= le16_to_cpup((__le16
*)&data
[14]);
179 ctrl
->wDelay
= le16_to_cpup((__le16
*)&data
[16]);
180 ctrl
->dwMaxVideoFrameSize
= get_unaligned_le32(&data
[18]);
181 ctrl
->dwMaxPayloadTransferSize
= get_unaligned_le32(&data
[22]);
184 ctrl
->dwClockFrequency
= get_unaligned_le32(&data
[26]);
185 ctrl
->bmFramingInfo
= data
[30];
186 ctrl
->bPreferedVersion
= data
[31];
187 ctrl
->bMinVersion
= data
[32];
188 ctrl
->bMaxVersion
= data
[33];
190 ctrl
->dwClockFrequency
= stream
->dev
->clock_frequency
;
191 ctrl
->bmFramingInfo
= 0;
192 ctrl
->bPreferedVersion
= 0;
193 ctrl
->bMinVersion
= 0;
194 ctrl
->bMaxVersion
= 0;
197 /* Some broken devices return null or wrong dwMaxVideoFrameSize and
198 * dwMaxPayloadTransferSize fields. Try to get the value from the
199 * format and frame descriptors.
201 uvc_fixup_video_ctrl(stream
, ctrl
);
209 static int uvc_set_video_ctrl(struct uvc_streaming
*stream
,
210 struct uvc_streaming_control
*ctrl
, int probe
)
216 size
= stream
->dev
->uvc_version
>= 0x0110 ? 34 : 26;
217 data
= kzalloc(size
, GFP_KERNEL
);
221 *(__le16
*)&data
[0] = cpu_to_le16(ctrl
->bmHint
);
222 data
[2] = ctrl
->bFormatIndex
;
223 data
[3] = ctrl
->bFrameIndex
;
224 *(__le32
*)&data
[4] = cpu_to_le32(ctrl
->dwFrameInterval
);
225 *(__le16
*)&data
[8] = cpu_to_le16(ctrl
->wKeyFrameRate
);
226 *(__le16
*)&data
[10] = cpu_to_le16(ctrl
->wPFrameRate
);
227 *(__le16
*)&data
[12] = cpu_to_le16(ctrl
->wCompQuality
);
228 *(__le16
*)&data
[14] = cpu_to_le16(ctrl
->wCompWindowSize
);
229 *(__le16
*)&data
[16] = cpu_to_le16(ctrl
->wDelay
);
230 put_unaligned_le32(ctrl
->dwMaxVideoFrameSize
, &data
[18]);
231 put_unaligned_le32(ctrl
->dwMaxPayloadTransferSize
, &data
[22]);
234 put_unaligned_le32(ctrl
->dwClockFrequency
, &data
[26]);
235 data
[30] = ctrl
->bmFramingInfo
;
236 data
[31] = ctrl
->bPreferedVersion
;
237 data
[32] = ctrl
->bMinVersion
;
238 data
[33] = ctrl
->bMaxVersion
;
241 ret
= __uvc_query_ctrl(stream
->dev
, UVC_SET_CUR
, 0, stream
->intfnum
,
242 probe
? UVC_VS_PROBE_CONTROL
: UVC_VS_COMMIT_CONTROL
, data
,
243 size
, uvc_timeout_param
);
245 uvc_printk(KERN_ERR
, "Failed to set UVC %s control : "
246 "%d (exp. %u).\n", probe
? "probe" : "commit",
255 int uvc_probe_video(struct uvc_streaming
*stream
,
256 struct uvc_streaming_control
*probe
)
258 struct uvc_streaming_control probe_min
, probe_max
;
263 mutex_lock(&stream
->mutex
);
265 /* Perform probing. The device should adjust the requested values
266 * according to its capabilities. However, some devices, namely the
267 * first generation UVC Logitech webcams, don't implement the Video
268 * Probe control properly, and just return the needed bandwidth. For
269 * that reason, if the needed bandwidth exceeds the maximum available
270 * bandwidth, try to lower the quality.
272 ret
= uvc_set_video_ctrl(stream
, probe
, 1);
276 /* Get the minimum and maximum values for compression settings. */
277 if (!(stream
->dev
->quirks
& UVC_QUIRK_PROBE_MINMAX
)) {
278 ret
= uvc_get_video_ctrl(stream
, &probe_min
, 1, UVC_GET_MIN
);
281 ret
= uvc_get_video_ctrl(stream
, &probe_max
, 1, UVC_GET_MAX
);
285 probe
->wCompQuality
= probe_max
.wCompQuality
;
288 for (i
= 0; i
< 2; ++i
) {
289 ret
= uvc_set_video_ctrl(stream
, probe
, 1);
292 ret
= uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_CUR
);
296 if (stream
->intf
->num_altsetting
== 1)
299 bandwidth
= probe
->dwMaxPayloadTransferSize
;
300 if (bandwidth
<= stream
->maxpsize
)
303 if (stream
->dev
->quirks
& UVC_QUIRK_PROBE_MINMAX
) {
308 /* TODO: negotiate compression parameters */
309 probe
->wKeyFrameRate
= probe_min
.wKeyFrameRate
;
310 probe
->wPFrameRate
= probe_min
.wPFrameRate
;
311 probe
->wCompQuality
= probe_max
.wCompQuality
;
312 probe
->wCompWindowSize
= probe_min
.wCompWindowSize
;
316 mutex_unlock(&stream
->mutex
);
320 int uvc_commit_video(struct uvc_streaming
*stream
,
321 struct uvc_streaming_control
*probe
)
323 return uvc_set_video_ctrl(stream
, probe
, 0);
326 /* ------------------------------------------------------------------------
330 /* Values for bmHeaderInfo (Video and Still Image Payload Headers, 2.4.3.3) */
331 #define UVC_STREAM_EOH (1 << 7)
332 #define UVC_STREAM_ERR (1 << 6)
333 #define UVC_STREAM_STI (1 << 5)
334 #define UVC_STREAM_RES (1 << 4)
335 #define UVC_STREAM_SCR (1 << 3)
336 #define UVC_STREAM_PTS (1 << 2)
337 #define UVC_STREAM_EOF (1 << 1)
338 #define UVC_STREAM_FID (1 << 0)
340 /* Video payload decoding is handled by uvc_video_decode_start(),
341 * uvc_video_decode_data() and uvc_video_decode_end().
343 * uvc_video_decode_start is called with URB data at the start of a bulk or
344 * isochronous payload. It processes header data and returns the header size
345 * in bytes if successful. If an error occurs, it returns a negative error
346 * code. The following error codes have special meanings.
348 * - EAGAIN informs the caller that the current video buffer should be marked
349 * as done, and that the function should be called again with the same data
350 * and a new video buffer. This is used when end of frame conditions can be
351 * reliably detected at the beginning of the next frame only.
353 * If an error other than -EAGAIN is returned, the caller will drop the current
354 * payload. No call to uvc_video_decode_data and uvc_video_decode_end will be
355 * made until the next payload. -ENODATA can be used to drop the current
356 * payload if no other error code is appropriate.
358 * uvc_video_decode_data is called for every URB with URB data. It copies the
359 * data to the video buffer.
361 * uvc_video_decode_end is called with header data at the end of a bulk or
362 * isochronous payload. It performs any additional header data processing and
363 * returns 0 or a negative error code if an error occured. As header data have
364 * already been processed by uvc_video_decode_start, this functions isn't
365 * required to perform sanity checks a second time.
367 * For isochronous transfers where a payload is always transfered in a single
368 * URB, the three functions will be called in a row.
370 * To let the decoder process header data and update its internal state even
371 * when no video buffer is available, uvc_video_decode_start must be prepared
372 * to be called with a NULL buf parameter. uvc_video_decode_data and
373 * uvc_video_decode_end will never be called with a NULL buffer.
375 static int uvc_video_decode_start(struct uvc_streaming
*stream
,
376 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
381 * - packet must be at least 2 bytes long
382 * - bHeaderLength value must be at least 2 bytes (see above)
383 * - bHeaderLength value can't be larger than the packet size.
385 if (len
< 2 || data
[0] < 2 || data
[0] > len
)
388 /* Skip payloads marked with the error bit ("error frames"). */
389 if (data
[1] & UVC_STREAM_ERR
) {
390 uvc_trace(UVC_TRACE_FRAME
, "Dropping payload (error bit "
395 fid
= data
[1] & UVC_STREAM_FID
;
397 /* Store the payload FID bit and return immediately when the buffer is
401 stream
->last_fid
= fid
;
405 /* Synchronize to the input stream by waiting for the FID bit to be
406 * toggled when the the buffer state is not UVC_BUF_STATE_ACTIVE.
407 * stream->last_fid is initialized to -1, so the first isochronous
408 * frame will always be in sync.
410 * If the device doesn't toggle the FID bit, invert stream->last_fid
411 * when the EOF bit is set to force synchronisation on the next packet.
413 if (buf
->state
!= UVC_BUF_STATE_ACTIVE
) {
416 if (fid
== stream
->last_fid
) {
417 uvc_trace(UVC_TRACE_FRAME
, "Dropping payload (out of "
419 if ((stream
->dev
->quirks
& UVC_QUIRK_STREAM_NO_FID
) &&
420 (data
[1] & UVC_STREAM_EOF
))
421 stream
->last_fid
^= UVC_STREAM_FID
;
425 if (uvc_clock_param
== CLOCK_MONOTONIC
)
428 ktime_get_real_ts(&ts
);
430 buf
->buf
.timestamp
.tv_sec
= ts
.tv_sec
;
431 buf
->buf
.timestamp
.tv_usec
= ts
.tv_nsec
/ NSEC_PER_USEC
;
433 /* TODO: Handle PTS and SCR. */
434 buf
->state
= UVC_BUF_STATE_ACTIVE
;
437 /* Mark the buffer as done if we're at the beginning of a new frame.
438 * End of frame detection is better implemented by checking the EOF
439 * bit (FID bit toggling is delayed by one frame compared to the EOF
440 * bit), but some devices don't set the bit at end of frame (and the
441 * last payload can be lost anyway). We thus must check if the FID has
444 * stream->last_fid is initialized to -1, so the first isochronous
445 * frame will never trigger an end of frame detection.
447 * Empty buffers (bytesused == 0) don't trigger end of frame detection
448 * as it doesn't make sense to return an empty buffer. This also
449 * avoids detecting end of frame conditions at FID toggling if the
450 * previous payload had the EOF bit set.
452 if (fid
!= stream
->last_fid
&& buf
->buf
.bytesused
!= 0) {
453 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (FID bit "
455 buf
->state
= UVC_BUF_STATE_READY
;
459 stream
->last_fid
= fid
;
464 static void uvc_video_decode_data(struct uvc_streaming
*stream
,
465 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
467 struct uvc_video_queue
*queue
= &stream
->queue
;
468 unsigned int maxlen
, nbytes
;
474 /* Copy the video data to the buffer. */
475 maxlen
= buf
->buf
.length
- buf
->buf
.bytesused
;
476 mem
= queue
->mem
+ buf
->buf
.m
.offset
+ buf
->buf
.bytesused
;
477 nbytes
= min((unsigned int)len
, maxlen
);
478 memcpy(mem
, data
, nbytes
);
479 buf
->buf
.bytesused
+= nbytes
;
481 /* Complete the current frame if the buffer size was exceeded. */
483 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (overflow).\n");
484 buf
->state
= UVC_BUF_STATE_READY
;
488 static void uvc_video_decode_end(struct uvc_streaming
*stream
,
489 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
491 /* Mark the buffer as done if the EOF marker is set. */
492 if (data
[1] & UVC_STREAM_EOF
&& buf
->buf
.bytesused
!= 0) {
493 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (EOF found).\n");
495 uvc_trace(UVC_TRACE_FRAME
, "EOF in empty payload.\n");
496 buf
->state
= UVC_BUF_STATE_READY
;
497 if (stream
->dev
->quirks
& UVC_QUIRK_STREAM_NO_FID
)
498 stream
->last_fid
^= UVC_STREAM_FID
;
502 /* Video payload encoding is handled by uvc_video_encode_header() and
503 * uvc_video_encode_data(). Only bulk transfers are currently supported.
505 * uvc_video_encode_header is called at the start of a payload. It adds header
506 * data to the transfer buffer and returns the header size. As the only known
507 * UVC output device transfers a whole frame in a single payload, the EOF bit
508 * is always set in the header.
510 * uvc_video_encode_data is called for every URB and copies the data from the
511 * video buffer to the transfer buffer.
513 static int uvc_video_encode_header(struct uvc_streaming
*stream
,
514 struct uvc_buffer
*buf
, __u8
*data
, int len
)
516 data
[0] = 2; /* Header length */
517 data
[1] = UVC_STREAM_EOH
| UVC_STREAM_EOF
518 | (stream
->last_fid
& UVC_STREAM_FID
);
522 static int uvc_video_encode_data(struct uvc_streaming
*stream
,
523 struct uvc_buffer
*buf
, __u8
*data
, int len
)
525 struct uvc_video_queue
*queue
= &stream
->queue
;
529 /* Copy video data to the URB buffer. */
530 mem
= queue
->mem
+ buf
->buf
.m
.offset
+ queue
->buf_used
;
531 nbytes
= min((unsigned int)len
, buf
->buf
.bytesused
- queue
->buf_used
);
532 nbytes
= min(stream
->bulk
.max_payload_size
- stream
->bulk
.payload_size
,
534 memcpy(data
, mem
, nbytes
);
536 queue
->buf_used
+= nbytes
;
541 /* ------------------------------------------------------------------------
546 * Completion handler for video URBs.
548 static void uvc_video_decode_isoc(struct urb
*urb
, struct uvc_streaming
*stream
,
549 struct uvc_buffer
*buf
)
554 for (i
= 0; i
< urb
->number_of_packets
; ++i
) {
555 if (urb
->iso_frame_desc
[i
].status
< 0) {
556 uvc_trace(UVC_TRACE_FRAME
, "USB isochronous frame "
557 "lost (%d).\n", urb
->iso_frame_desc
[i
].status
);
561 /* Decode the payload header. */
562 mem
= urb
->transfer_buffer
+ urb
->iso_frame_desc
[i
].offset
;
564 ret
= uvc_video_decode_start(stream
, buf
, mem
,
565 urb
->iso_frame_desc
[i
].actual_length
);
567 buf
= uvc_queue_next_buffer(&stream
->queue
,
569 } while (ret
== -EAGAIN
);
574 /* Decode the payload data. */
575 uvc_video_decode_data(stream
, buf
, mem
+ ret
,
576 urb
->iso_frame_desc
[i
].actual_length
- ret
);
578 /* Process the header again. */
579 uvc_video_decode_end(stream
, buf
, mem
,
580 urb
->iso_frame_desc
[i
].actual_length
);
582 if (buf
->state
== UVC_BUF_STATE_READY
)
583 buf
= uvc_queue_next_buffer(&stream
->queue
, buf
);
587 static void uvc_video_decode_bulk(struct urb
*urb
, struct uvc_streaming
*stream
,
588 struct uvc_buffer
*buf
)
593 if (urb
->actual_length
== 0)
596 mem
= urb
->transfer_buffer
;
597 len
= urb
->actual_length
;
598 stream
->bulk
.payload_size
+= len
;
600 /* If the URB is the first of its payload, decode and save the
603 if (stream
->bulk
.header_size
== 0 && !stream
->bulk
.skip_payload
) {
605 ret
= uvc_video_decode_start(stream
, buf
, mem
, len
);
607 buf
= uvc_queue_next_buffer(&stream
->queue
,
609 } while (ret
== -EAGAIN
);
611 /* If an error occured skip the rest of the payload. */
612 if (ret
< 0 || buf
== NULL
) {
613 stream
->bulk
.skip_payload
= 1;
615 memcpy(stream
->bulk
.header
, mem
, ret
);
616 stream
->bulk
.header_size
= ret
;
623 /* The buffer queue might have been cancelled while a bulk transfer
624 * was in progress, so we can reach here with buf equal to NULL. Make
625 * sure buf is never dereferenced if NULL.
628 /* Process video data. */
629 if (!stream
->bulk
.skip_payload
&& buf
!= NULL
)
630 uvc_video_decode_data(stream
, buf
, mem
, len
);
632 /* Detect the payload end by a URB smaller than the maximum size (or
633 * a payload size equal to the maximum) and process the header again.
635 if (urb
->actual_length
< urb
->transfer_buffer_length
||
636 stream
->bulk
.payload_size
>= stream
->bulk
.max_payload_size
) {
637 if (!stream
->bulk
.skip_payload
&& buf
!= NULL
) {
638 uvc_video_decode_end(stream
, buf
, stream
->bulk
.header
,
639 stream
->bulk
.payload_size
);
640 if (buf
->state
== UVC_BUF_STATE_READY
)
641 buf
= uvc_queue_next_buffer(&stream
->queue
,
645 stream
->bulk
.header_size
= 0;
646 stream
->bulk
.skip_payload
= 0;
647 stream
->bulk
.payload_size
= 0;
651 static void uvc_video_encode_bulk(struct urb
*urb
, struct uvc_streaming
*stream
,
652 struct uvc_buffer
*buf
)
654 u8
*mem
= urb
->transfer_buffer
;
655 int len
= stream
->urb_size
, ret
;
658 urb
->transfer_buffer_length
= 0;
662 /* If the URB is the first of its payload, add the header. */
663 if (stream
->bulk
.header_size
== 0) {
664 ret
= uvc_video_encode_header(stream
, buf
, mem
, len
);
665 stream
->bulk
.header_size
= ret
;
666 stream
->bulk
.payload_size
+= ret
;
671 /* Process video data. */
672 ret
= uvc_video_encode_data(stream
, buf
, mem
, len
);
674 stream
->bulk
.payload_size
+= ret
;
677 if (buf
->buf
.bytesused
== stream
->queue
.buf_used
||
678 stream
->bulk
.payload_size
== stream
->bulk
.max_payload_size
) {
679 if (buf
->buf
.bytesused
== stream
->queue
.buf_used
) {
680 stream
->queue
.buf_used
= 0;
681 buf
->state
= UVC_BUF_STATE_READY
;
682 uvc_queue_next_buffer(&stream
->queue
, buf
);
683 stream
->last_fid
^= UVC_STREAM_FID
;
686 stream
->bulk
.header_size
= 0;
687 stream
->bulk
.payload_size
= 0;
690 urb
->transfer_buffer_length
= stream
->urb_size
- len
;
693 static void uvc_video_complete(struct urb
*urb
)
695 struct uvc_streaming
*stream
= urb
->context
;
696 struct uvc_video_queue
*queue
= &stream
->queue
;
697 struct uvc_buffer
*buf
= NULL
;
701 switch (urb
->status
) {
706 uvc_printk(KERN_WARNING
, "Non-zero status (%d) in video "
707 "completion handler.\n", urb
->status
);
709 case -ENOENT
: /* usb_kill_urb() called. */
713 case -ECONNRESET
: /* usb_unlink_urb() called. */
714 case -ESHUTDOWN
: /* The endpoint is being disabled. */
715 uvc_queue_cancel(queue
, urb
->status
== -ESHUTDOWN
);
719 spin_lock_irqsave(&queue
->irqlock
, flags
);
720 if (!list_empty(&queue
->irqqueue
))
721 buf
= list_first_entry(&queue
->irqqueue
, struct uvc_buffer
,
723 spin_unlock_irqrestore(&queue
->irqlock
, flags
);
725 stream
->decode(urb
, stream
, buf
);
727 if ((ret
= usb_submit_urb(urb
, GFP_ATOMIC
)) < 0) {
728 uvc_printk(KERN_ERR
, "Failed to resubmit video URB (%d).\n",
734 * Free transfer buffers.
736 static void uvc_free_urb_buffers(struct uvc_streaming
*stream
)
740 for (i
= 0; i
< UVC_URBS
; ++i
) {
741 if (stream
->urb_buffer
[i
]) {
742 usb_buffer_free(stream
->dev
->udev
, stream
->urb_size
,
743 stream
->urb_buffer
[i
], stream
->urb_dma
[i
]);
744 stream
->urb_buffer
[i
] = NULL
;
748 stream
->urb_size
= 0;
752 * Allocate transfer buffers. This function can be called with buffers
753 * already allocated when resuming from suspend, in which case it will
754 * return without touching the buffers.
756 * Limit the buffer size to UVC_MAX_PACKETS bulk/isochronous packets. If the
757 * system is too low on memory try successively smaller numbers of packets
758 * until allocation succeeds.
760 * Return the number of allocated packets on success or 0 when out of memory.
762 static int uvc_alloc_urb_buffers(struct uvc_streaming
*stream
,
763 unsigned int size
, unsigned int psize
, gfp_t gfp_flags
)
765 unsigned int npackets
;
768 /* Buffers are already allocated, bail out. */
769 if (stream
->urb_size
)
770 return stream
->urb_size
/ psize
;
772 /* Compute the number of packets. Bulk endpoints might transfer UVC
773 * payloads accross multiple URBs.
775 npackets
= DIV_ROUND_UP(size
, psize
);
776 if (npackets
> UVC_MAX_PACKETS
)
777 npackets
= UVC_MAX_PACKETS
;
779 /* Retry allocations until one succeed. */
780 for (; npackets
> 1; npackets
/= 2) {
781 for (i
= 0; i
< UVC_URBS
; ++i
) {
782 stream
->urb_size
= psize
* npackets
;
783 stream
->urb_buffer
[i
] = usb_buffer_alloc(
784 stream
->dev
->udev
, stream
->urb_size
,
785 gfp_flags
| __GFP_NOWARN
, &stream
->urb_dma
[i
]);
786 if (!stream
->urb_buffer
[i
]) {
787 uvc_free_urb_buffers(stream
);
793 uvc_trace(UVC_TRACE_VIDEO
, "Allocated %u URB buffers "
794 "of %ux%u bytes each.\n", UVC_URBS
, npackets
,
800 uvc_trace(UVC_TRACE_VIDEO
, "Failed to allocate URB buffers (%u bytes "
801 "per packet).\n", psize
);
806 * Uninitialize isochronous/bulk URBs and free transfer buffers.
808 static void uvc_uninit_video(struct uvc_streaming
*stream
, int free_buffers
)
813 for (i
= 0; i
< UVC_URBS
; ++i
) {
814 urb
= stream
->urb
[i
];
820 stream
->urb
[i
] = NULL
;
824 uvc_free_urb_buffers(stream
);
828 * Initialize isochronous URBs and allocate transfer buffers. The packet size
829 * is given by the endpoint.
831 static int uvc_init_video_isoc(struct uvc_streaming
*stream
,
832 struct usb_host_endpoint
*ep
, gfp_t gfp_flags
)
835 unsigned int npackets
, i
, j
;
839 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
);
840 psize
= (psize
& 0x07ff) * (1 + ((psize
>> 11) & 3));
841 size
= stream
->ctrl
.dwMaxVideoFrameSize
;
843 npackets
= uvc_alloc_urb_buffers(stream
, size
, psize
, gfp_flags
);
847 size
= npackets
* psize
;
849 for (i
= 0; i
< UVC_URBS
; ++i
) {
850 urb
= usb_alloc_urb(npackets
, gfp_flags
);
852 uvc_uninit_video(stream
, 1);
856 urb
->dev
= stream
->dev
->udev
;
857 urb
->context
= stream
;
858 urb
->pipe
= usb_rcvisocpipe(stream
->dev
->udev
,
859 ep
->desc
.bEndpointAddress
);
860 urb
->transfer_flags
= URB_ISO_ASAP
| URB_NO_TRANSFER_DMA_MAP
;
861 urb
->interval
= ep
->desc
.bInterval
;
862 urb
->transfer_buffer
= stream
->urb_buffer
[i
];
863 urb
->transfer_dma
= stream
->urb_dma
[i
];
864 urb
->complete
= uvc_video_complete
;
865 urb
->number_of_packets
= npackets
;
866 urb
->transfer_buffer_length
= size
;
868 for (j
= 0; j
< npackets
; ++j
) {
869 urb
->iso_frame_desc
[j
].offset
= j
* psize
;
870 urb
->iso_frame_desc
[j
].length
= psize
;
873 stream
->urb
[i
] = urb
;
880 * Initialize bulk URBs and allocate transfer buffers. The packet size is
881 * given by the endpoint.
883 static int uvc_init_video_bulk(struct uvc_streaming
*stream
,
884 struct usb_host_endpoint
*ep
, gfp_t gfp_flags
)
887 unsigned int npackets
, pipe
, i
;
891 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
) & 0x07ff;
892 size
= stream
->ctrl
.dwMaxPayloadTransferSize
;
893 stream
->bulk
.max_payload_size
= size
;
895 npackets
= uvc_alloc_urb_buffers(stream
, size
, psize
, gfp_flags
);
899 size
= npackets
* psize
;
901 if (usb_endpoint_dir_in(&ep
->desc
))
902 pipe
= usb_rcvbulkpipe(stream
->dev
->udev
,
903 ep
->desc
.bEndpointAddress
);
905 pipe
= usb_sndbulkpipe(stream
->dev
->udev
,
906 ep
->desc
.bEndpointAddress
);
908 if (stream
->type
== V4L2_BUF_TYPE_VIDEO_OUTPUT
)
911 for (i
= 0; i
< UVC_URBS
; ++i
) {
912 urb
= usb_alloc_urb(0, gfp_flags
);
914 uvc_uninit_video(stream
, 1);
918 usb_fill_bulk_urb(urb
, stream
->dev
->udev
, pipe
,
919 stream
->urb_buffer
[i
], size
, uvc_video_complete
,
921 urb
->transfer_flags
= URB_NO_TRANSFER_DMA_MAP
;
922 urb
->transfer_dma
= stream
->urb_dma
[i
];
924 stream
->urb
[i
] = urb
;
931 * Initialize isochronous/bulk URBs and allocate transfer buffers.
933 static int uvc_init_video(struct uvc_streaming
*stream
, gfp_t gfp_flags
)
935 struct usb_interface
*intf
= stream
->intf
;
936 struct usb_host_endpoint
*ep
;
940 stream
->last_fid
= -1;
941 stream
->bulk
.header_size
= 0;
942 stream
->bulk
.skip_payload
= 0;
943 stream
->bulk
.payload_size
= 0;
945 if (intf
->num_altsetting
> 1) {
946 struct usb_host_endpoint
*best_ep
= NULL
;
947 unsigned int best_psize
= 3 * 1024;
948 unsigned int bandwidth
;
949 unsigned int uninitialized_var(altsetting
);
950 int intfnum
= stream
->intfnum
;
952 /* Isochronous endpoint, select the alternate setting. */
953 bandwidth
= stream
->ctrl
.dwMaxPayloadTransferSize
;
955 if (bandwidth
== 0) {
956 uvc_trace(UVC_TRACE_VIDEO
, "Device requested null "
957 "bandwidth, defaulting to lowest.\n");
960 uvc_trace(UVC_TRACE_VIDEO
, "Device requested %u "
961 "B/frame bandwidth.\n", bandwidth
);
964 for (i
= 0; i
< intf
->num_altsetting
; ++i
) {
965 struct usb_host_interface
*alts
;
968 alts
= &intf
->altsetting
[i
];
969 ep
= uvc_find_endpoint(alts
,
970 stream
->header
.bEndpointAddress
);
974 /* Check if the bandwidth is high enough. */
975 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
);
976 psize
= (psize
& 0x07ff) * (1 + ((psize
>> 11) & 3));
977 if (psize
>= bandwidth
&& psize
<= best_psize
) {
984 if (best_ep
== NULL
) {
985 uvc_trace(UVC_TRACE_VIDEO
, "No fast enough alt setting "
986 "for requested bandwidth.\n");
990 uvc_trace(UVC_TRACE_VIDEO
, "Selecting alternate setting %u "
991 "(%u B/frame bandwidth).\n", altsetting
, best_psize
);
993 ret
= usb_set_interface(stream
->dev
->udev
, intfnum
, altsetting
);
997 ret
= uvc_init_video_isoc(stream
, best_ep
, gfp_flags
);
999 /* Bulk endpoint, proceed to URB initialization. */
1000 ep
= uvc_find_endpoint(&intf
->altsetting
[0],
1001 stream
->header
.bEndpointAddress
);
1005 ret
= uvc_init_video_bulk(stream
, ep
, gfp_flags
);
1011 /* Submit the URBs. */
1012 for (i
= 0; i
< UVC_URBS
; ++i
) {
1013 ret
= usb_submit_urb(stream
->urb
[i
], gfp_flags
);
1015 uvc_printk(KERN_ERR
, "Failed to submit URB %u "
1017 uvc_uninit_video(stream
, 1);
1025 /* --------------------------------------------------------------------------
1030 * Stop streaming without disabling the video queue.
1032 * To let userspace applications resume without trouble, we must not touch the
1033 * video buffers in any way. We mark the device as frozen to make sure the URB
1034 * completion handler won't try to cancel the queue when we kill the URBs.
1036 int uvc_video_suspend(struct uvc_streaming
*stream
)
1038 if (!uvc_queue_streaming(&stream
->queue
))
1042 uvc_uninit_video(stream
, 0);
1043 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1048 * Reconfigure the video interface and restart streaming if it was enabled
1051 * If an error occurs, disable the video queue. This will wake all pending
1052 * buffers, making sure userspace applications are notified of the problem
1053 * instead of waiting forever.
1055 int uvc_video_resume(struct uvc_streaming
*stream
)
1061 ret
= uvc_commit_video(stream
, &stream
->ctrl
);
1063 uvc_queue_enable(&stream
->queue
, 0);
1067 if (!uvc_queue_streaming(&stream
->queue
))
1070 ret
= uvc_init_video(stream
, GFP_NOIO
);
1072 uvc_queue_enable(&stream
->queue
, 0);
1077 /* ------------------------------------------------------------------------
1082 * Initialize the UVC video device by switching to alternate setting 0 and
1083 * retrieve the default format.
1085 * Some cameras (namely the Fuji Finepix) set the format and frame
1086 * indexes to zero. The UVC standard doesn't clearly make this a spec
1087 * violation, so try to silently fix the values if possible.
1089 * This function is called before registering the device with V4L.
1091 int uvc_video_init(struct uvc_streaming
*stream
)
1093 struct uvc_streaming_control
*probe
= &stream
->ctrl
;
1094 struct uvc_format
*format
= NULL
;
1095 struct uvc_frame
*frame
= NULL
;
1099 if (stream
->nformats
== 0) {
1100 uvc_printk(KERN_INFO
, "No supported video formats found.\n");
1104 atomic_set(&stream
->active
, 0);
1106 /* Initialize the video buffers queue. */
1107 uvc_queue_init(&stream
->queue
, stream
->type
);
1109 /* Alternate setting 0 should be the default, yet the XBox Live Vision
1110 * Cam (and possibly other devices) crash or otherwise misbehave if
1111 * they don't receive a SET_INTERFACE request before any other video
1114 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1116 /* Set the streaming probe control with default streaming parameters
1117 * retrieved from the device. Webcams that don't suport GET_DEF
1118 * requests on the probe control will just keep their current streaming
1121 if (uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_DEF
) == 0)
1122 uvc_set_video_ctrl(stream
, probe
, 1);
1124 /* Initialize the streaming parameters with the probe control current
1125 * value. This makes sure SET_CUR requests on the streaming commit
1126 * control will always use values retrieved from a successful GET_CUR
1127 * request on the probe control, as required by the UVC specification.
1129 ret
= uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_CUR
);
1133 /* Check if the default format descriptor exists. Use the first
1134 * available format otherwise.
1136 for (i
= stream
->nformats
; i
> 0; --i
) {
1137 format
= &stream
->format
[i
-1];
1138 if (format
->index
== probe
->bFormatIndex
)
1142 if (format
->nframes
== 0) {
1143 uvc_printk(KERN_INFO
, "No frame descriptor found for the "
1144 "default format.\n");
1148 /* Zero bFrameIndex might be correct. Stream-based formats (including
1149 * MPEG-2 TS and DV) do not support frames but have a dummy frame
1150 * descriptor with bFrameIndex set to zero. If the default frame
1151 * descriptor is not found, use the first available frame.
1153 for (i
= format
->nframes
; i
> 0; --i
) {
1154 frame
= &format
->frame
[i
-1];
1155 if (frame
->bFrameIndex
== probe
->bFrameIndex
)
1159 probe
->bFormatIndex
= format
->index
;
1160 probe
->bFrameIndex
= frame
->bFrameIndex
;
1162 stream
->cur_format
= format
;
1163 stream
->cur_frame
= frame
;
1165 /* Select the video decoding function */
1166 if (stream
->type
== V4L2_BUF_TYPE_VIDEO_CAPTURE
) {
1167 if (stream
->dev
->quirks
& UVC_QUIRK_BUILTIN_ISIGHT
)
1168 stream
->decode
= uvc_video_decode_isight
;
1169 else if (stream
->intf
->num_altsetting
> 1)
1170 stream
->decode
= uvc_video_decode_isoc
;
1172 stream
->decode
= uvc_video_decode_bulk
;
1174 if (stream
->intf
->num_altsetting
== 1)
1175 stream
->decode
= uvc_video_encode_bulk
;
1177 uvc_printk(KERN_INFO
, "Isochronous endpoints are not "
1178 "supported for video output devices.\n");
1187 * Enable or disable the video stream.
1189 int uvc_video_enable(struct uvc_streaming
*stream
, int enable
)
1194 uvc_uninit_video(stream
, 1);
1195 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1196 uvc_queue_enable(&stream
->queue
, 0);
1200 if ((stream
->cur_format
->flags
& UVC_FMT_FLAG_COMPRESSED
) ||
1202 stream
->queue
.flags
&= ~UVC_QUEUE_DROP_INCOMPLETE
;
1204 stream
->queue
.flags
|= UVC_QUEUE_DROP_INCOMPLETE
;
1206 ret
= uvc_queue_enable(&stream
->queue
, 1);
1210 /* Commit the streaming parameters. */
1211 ret
= uvc_commit_video(stream
, &stream
->ctrl
);
1215 return uvc_init_video(stream
, GFP_KERNEL
);