2 * uvc_video.c -- USB Video Class driver - Video handling
4 * Copyright (C) 2005-2010
5 * Laurent Pinchart (laurent.pinchart@ideasonboard.com)
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 <linux/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 static const char *uvc_query_name(__u8 query
)
72 int uvc_query_ctrl(struct uvc_device
*dev
, __u8 query
, __u8 unit
,
73 __u8 intfnum
, __u8 cs
, void *data
, __u16 size
)
77 ret
= __uvc_query_ctrl(dev
, query
, unit
, intfnum
, cs
, data
, size
,
78 UVC_CTRL_CONTROL_TIMEOUT
);
80 uvc_printk(KERN_ERR
, "Failed to query (%s) UVC control %u on "
81 "unit %u: %d (exp. %u).\n", uvc_query_name(query
), cs
,
89 static void uvc_fixup_video_ctrl(struct uvc_streaming
*stream
,
90 struct uvc_streaming_control
*ctrl
)
92 struct uvc_format
*format
= NULL
;
93 struct uvc_frame
*frame
= NULL
;
96 for (i
= 0; i
< stream
->nformats
; ++i
) {
97 if (stream
->format
[i
].index
== ctrl
->bFormatIndex
) {
98 format
= &stream
->format
[i
];
106 for (i
= 0; i
< format
->nframes
; ++i
) {
107 if (format
->frame
[i
].bFrameIndex
== ctrl
->bFrameIndex
) {
108 frame
= &format
->frame
[i
];
116 if (!(format
->flags
& UVC_FMT_FLAG_COMPRESSED
) ||
117 (ctrl
->dwMaxVideoFrameSize
== 0 &&
118 stream
->dev
->uvc_version
< 0x0110))
119 ctrl
->dwMaxVideoFrameSize
=
120 frame
->dwMaxVideoFrameBufferSize
;
122 if (!(format
->flags
& UVC_FMT_FLAG_COMPRESSED
) &&
123 stream
->dev
->quirks
& UVC_QUIRK_FIX_BANDWIDTH
&&
124 stream
->intf
->num_altsetting
> 1) {
128 interval
= (ctrl
->dwFrameInterval
> 100000)
129 ? ctrl
->dwFrameInterval
130 : frame
->dwFrameInterval
[0];
132 /* Compute a bandwidth estimation by multiplying the frame
133 * size by the number of video frames per second, divide the
134 * result by the number of USB frames (or micro-frames for
135 * high-speed devices) per second and add the UVC header size
136 * (assumed to be 12 bytes long).
138 bandwidth
= frame
->wWidth
* frame
->wHeight
/ 8 * format
->bpp
;
139 bandwidth
*= 10000000 / interval
+ 1;
141 if (stream
->dev
->udev
->speed
== USB_SPEED_HIGH
)
145 /* The bandwidth estimate is too low for many cameras. Don't use
146 * maximum packet sizes lower than 1024 bytes to try and work
147 * around the problem. According to measurements done on two
148 * different camera models, the value is high enough to get most
149 * resolutions working while not preventing two simultaneous
150 * VGA streams at 15 fps.
152 bandwidth
= max_t(u32
, bandwidth
, 1024);
154 ctrl
->dwMaxPayloadTransferSize
= bandwidth
;
158 static int uvc_get_video_ctrl(struct uvc_streaming
*stream
,
159 struct uvc_streaming_control
*ctrl
, int probe
, __u8 query
)
165 size
= stream
->dev
->uvc_version
>= 0x0110 ? 34 : 26;
166 if ((stream
->dev
->quirks
& UVC_QUIRK_PROBE_DEF
) &&
167 query
== UVC_GET_DEF
)
170 data
= kmalloc(size
, GFP_KERNEL
);
174 ret
= __uvc_query_ctrl(stream
->dev
, query
, 0, stream
->intfnum
,
175 probe
? UVC_VS_PROBE_CONTROL
: UVC_VS_COMMIT_CONTROL
, data
,
176 size
, uvc_timeout_param
);
178 if ((query
== UVC_GET_MIN
|| query
== UVC_GET_MAX
) && ret
== 2) {
179 /* Some cameras, mostly based on Bison Electronics chipsets,
180 * answer a GET_MIN or GET_MAX request with the wCompQuality
183 uvc_warn_once(stream
->dev
, UVC_WARN_MINMAX
, "UVC non "
184 "compliance - GET_MIN/MAX(PROBE) incorrectly "
185 "supported. Enabling workaround.\n");
186 memset(ctrl
, 0, sizeof *ctrl
);
187 ctrl
->wCompQuality
= le16_to_cpup((__le16
*)data
);
190 } else if (query
== UVC_GET_DEF
&& probe
== 1 && ret
!= size
) {
191 /* Many cameras don't support the GET_DEF request on their
192 * video probe control. Warn once and return, the caller will
193 * fall back to GET_CUR.
195 uvc_warn_once(stream
->dev
, UVC_WARN_PROBE_DEF
, "UVC non "
196 "compliance - GET_DEF(PROBE) not supported. "
197 "Enabling workaround.\n");
200 } else if (ret
!= size
) {
201 uvc_printk(KERN_ERR
, "Failed to query (%u) UVC %s control : "
202 "%d (exp. %u).\n", query
, probe
? "probe" : "commit",
208 ctrl
->bmHint
= le16_to_cpup((__le16
*)&data
[0]);
209 ctrl
->bFormatIndex
= data
[2];
210 ctrl
->bFrameIndex
= data
[3];
211 ctrl
->dwFrameInterval
= le32_to_cpup((__le32
*)&data
[4]);
212 ctrl
->wKeyFrameRate
= le16_to_cpup((__le16
*)&data
[8]);
213 ctrl
->wPFrameRate
= le16_to_cpup((__le16
*)&data
[10]);
214 ctrl
->wCompQuality
= le16_to_cpup((__le16
*)&data
[12]);
215 ctrl
->wCompWindowSize
= le16_to_cpup((__le16
*)&data
[14]);
216 ctrl
->wDelay
= le16_to_cpup((__le16
*)&data
[16]);
217 ctrl
->dwMaxVideoFrameSize
= get_unaligned_le32(&data
[18]);
218 ctrl
->dwMaxPayloadTransferSize
= get_unaligned_le32(&data
[22]);
221 ctrl
->dwClockFrequency
= get_unaligned_le32(&data
[26]);
222 ctrl
->bmFramingInfo
= data
[30];
223 ctrl
->bPreferedVersion
= data
[31];
224 ctrl
->bMinVersion
= data
[32];
225 ctrl
->bMaxVersion
= data
[33];
227 ctrl
->dwClockFrequency
= stream
->dev
->clock_frequency
;
228 ctrl
->bmFramingInfo
= 0;
229 ctrl
->bPreferedVersion
= 0;
230 ctrl
->bMinVersion
= 0;
231 ctrl
->bMaxVersion
= 0;
234 /* Some broken devices return null or wrong dwMaxVideoFrameSize and
235 * dwMaxPayloadTransferSize fields. Try to get the value from the
236 * format and frame descriptors.
238 uvc_fixup_video_ctrl(stream
, ctrl
);
246 static int uvc_set_video_ctrl(struct uvc_streaming
*stream
,
247 struct uvc_streaming_control
*ctrl
, int probe
)
253 size
= stream
->dev
->uvc_version
>= 0x0110 ? 34 : 26;
254 data
= kzalloc(size
, GFP_KERNEL
);
258 *(__le16
*)&data
[0] = cpu_to_le16(ctrl
->bmHint
);
259 data
[2] = ctrl
->bFormatIndex
;
260 data
[3] = ctrl
->bFrameIndex
;
261 *(__le32
*)&data
[4] = cpu_to_le32(ctrl
->dwFrameInterval
);
262 *(__le16
*)&data
[8] = cpu_to_le16(ctrl
->wKeyFrameRate
);
263 *(__le16
*)&data
[10] = cpu_to_le16(ctrl
->wPFrameRate
);
264 *(__le16
*)&data
[12] = cpu_to_le16(ctrl
->wCompQuality
);
265 *(__le16
*)&data
[14] = cpu_to_le16(ctrl
->wCompWindowSize
);
266 *(__le16
*)&data
[16] = cpu_to_le16(ctrl
->wDelay
);
267 put_unaligned_le32(ctrl
->dwMaxVideoFrameSize
, &data
[18]);
268 put_unaligned_le32(ctrl
->dwMaxPayloadTransferSize
, &data
[22]);
271 put_unaligned_le32(ctrl
->dwClockFrequency
, &data
[26]);
272 data
[30] = ctrl
->bmFramingInfo
;
273 data
[31] = ctrl
->bPreferedVersion
;
274 data
[32] = ctrl
->bMinVersion
;
275 data
[33] = ctrl
->bMaxVersion
;
278 ret
= __uvc_query_ctrl(stream
->dev
, UVC_SET_CUR
, 0, stream
->intfnum
,
279 probe
? UVC_VS_PROBE_CONTROL
: UVC_VS_COMMIT_CONTROL
, data
,
280 size
, uvc_timeout_param
);
282 uvc_printk(KERN_ERR
, "Failed to set UVC %s control : "
283 "%d (exp. %u).\n", probe
? "probe" : "commit",
292 int uvc_probe_video(struct uvc_streaming
*stream
,
293 struct uvc_streaming_control
*probe
)
295 struct uvc_streaming_control probe_min
, probe_max
;
300 /* Perform probing. The device should adjust the requested values
301 * according to its capabilities. However, some devices, namely the
302 * first generation UVC Logitech webcams, don't implement the Video
303 * Probe control properly, and just return the needed bandwidth. For
304 * that reason, if the needed bandwidth exceeds the maximum available
305 * bandwidth, try to lower the quality.
307 ret
= uvc_set_video_ctrl(stream
, probe
, 1);
311 /* Get the minimum and maximum values for compression settings. */
312 if (!(stream
->dev
->quirks
& UVC_QUIRK_PROBE_MINMAX
)) {
313 ret
= uvc_get_video_ctrl(stream
, &probe_min
, 1, UVC_GET_MIN
);
316 ret
= uvc_get_video_ctrl(stream
, &probe_max
, 1, UVC_GET_MAX
);
320 probe
->wCompQuality
= probe_max
.wCompQuality
;
323 for (i
= 0; i
< 2; ++i
) {
324 ret
= uvc_set_video_ctrl(stream
, probe
, 1);
327 ret
= uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_CUR
);
331 if (stream
->intf
->num_altsetting
== 1)
334 bandwidth
= probe
->dwMaxPayloadTransferSize
;
335 if (bandwidth
<= stream
->maxpsize
)
338 if (stream
->dev
->quirks
& UVC_QUIRK_PROBE_MINMAX
) {
343 /* TODO: negotiate compression parameters */
344 probe
->wKeyFrameRate
= probe_min
.wKeyFrameRate
;
345 probe
->wPFrameRate
= probe_min
.wPFrameRate
;
346 probe
->wCompQuality
= probe_max
.wCompQuality
;
347 probe
->wCompWindowSize
= probe_min
.wCompWindowSize
;
354 int uvc_commit_video(struct uvc_streaming
*stream
,
355 struct uvc_streaming_control
*probe
)
357 return uvc_set_video_ctrl(stream
, probe
, 0);
360 /* ------------------------------------------------------------------------
364 /* Values for bmHeaderInfo (Video and Still Image Payload Headers, 2.4.3.3) */
365 #define UVC_STREAM_EOH (1 << 7)
366 #define UVC_STREAM_ERR (1 << 6)
367 #define UVC_STREAM_STI (1 << 5)
368 #define UVC_STREAM_RES (1 << 4)
369 #define UVC_STREAM_SCR (1 << 3)
370 #define UVC_STREAM_PTS (1 << 2)
371 #define UVC_STREAM_EOF (1 << 1)
372 #define UVC_STREAM_FID (1 << 0)
374 /* Video payload decoding is handled by uvc_video_decode_start(),
375 * uvc_video_decode_data() and uvc_video_decode_end().
377 * uvc_video_decode_start is called with URB data at the start of a bulk or
378 * isochronous payload. It processes header data and returns the header size
379 * in bytes if successful. If an error occurs, it returns a negative error
380 * code. The following error codes have special meanings.
382 * - EAGAIN informs the caller that the current video buffer should be marked
383 * as done, and that the function should be called again with the same data
384 * and a new video buffer. This is used when end of frame conditions can be
385 * reliably detected at the beginning of the next frame only.
387 * If an error other than -EAGAIN is returned, the caller will drop the current
388 * payload. No call to uvc_video_decode_data and uvc_video_decode_end will be
389 * made until the next payload. -ENODATA can be used to drop the current
390 * payload if no other error code is appropriate.
392 * uvc_video_decode_data is called for every URB with URB data. It copies the
393 * data to the video buffer.
395 * uvc_video_decode_end is called with header data at the end of a bulk or
396 * isochronous payload. It performs any additional header data processing and
397 * returns 0 or a negative error code if an error occurred. As header data have
398 * already been processed by uvc_video_decode_start, this functions isn't
399 * required to perform sanity checks a second time.
401 * For isochronous transfers where a payload is always transferred in a single
402 * URB, the three functions will be called in a row.
404 * To let the decoder process header data and update its internal state even
405 * when no video buffer is available, uvc_video_decode_start must be prepared
406 * to be called with a NULL buf parameter. uvc_video_decode_data and
407 * uvc_video_decode_end will never be called with a NULL buffer.
409 static int uvc_video_decode_start(struct uvc_streaming
*stream
,
410 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
415 * - packet must be at least 2 bytes long
416 * - bHeaderLength value must be at least 2 bytes (see above)
417 * - bHeaderLength value can't be larger than the packet size.
419 if (len
< 2 || data
[0] < 2 || data
[0] > len
)
422 /* Skip payloads marked with the error bit ("error frames"). */
423 if (data
[1] & UVC_STREAM_ERR
) {
424 uvc_trace(UVC_TRACE_FRAME
, "Dropping payload (error bit "
429 fid
= data
[1] & UVC_STREAM_FID
;
431 /* Increase the sequence number regardless of any buffer states, so
432 * that discontinuous sequence numbers always indicate lost frames.
434 if (stream
->last_fid
!= fid
)
437 /* Store the payload FID bit and return immediately when the buffer is
441 stream
->last_fid
= fid
;
445 /* Synchronize to the input stream by waiting for the FID bit to be
446 * toggled when the the buffer state is not UVC_BUF_STATE_ACTIVE.
447 * stream->last_fid is initialized to -1, so the first isochronous
448 * frame will always be in sync.
450 * If the device doesn't toggle the FID bit, invert stream->last_fid
451 * when the EOF bit is set to force synchronisation on the next packet.
453 if (buf
->state
!= UVC_BUF_STATE_ACTIVE
) {
456 if (fid
== stream
->last_fid
) {
457 uvc_trace(UVC_TRACE_FRAME
, "Dropping payload (out of "
459 if ((stream
->dev
->quirks
& UVC_QUIRK_STREAM_NO_FID
) &&
460 (data
[1] & UVC_STREAM_EOF
))
461 stream
->last_fid
^= UVC_STREAM_FID
;
465 if (uvc_clock_param
== CLOCK_MONOTONIC
)
468 ktime_get_real_ts(&ts
);
470 buf
->buf
.sequence
= stream
->sequence
;
471 buf
->buf
.timestamp
.tv_sec
= ts
.tv_sec
;
472 buf
->buf
.timestamp
.tv_usec
= ts
.tv_nsec
/ NSEC_PER_USEC
;
474 /* TODO: Handle PTS and SCR. */
475 buf
->state
= UVC_BUF_STATE_ACTIVE
;
478 /* Mark the buffer as done if we're at the beginning of a new frame.
479 * End of frame detection is better implemented by checking the EOF
480 * bit (FID bit toggling is delayed by one frame compared to the EOF
481 * bit), but some devices don't set the bit at end of frame (and the
482 * last payload can be lost anyway). We thus must check if the FID has
485 * stream->last_fid is initialized to -1, so the first isochronous
486 * frame will never trigger an end of frame detection.
488 * Empty buffers (bytesused == 0) don't trigger end of frame detection
489 * as it doesn't make sense to return an empty buffer. This also
490 * avoids detecting end of frame conditions at FID toggling if the
491 * previous payload had the EOF bit set.
493 if (fid
!= stream
->last_fid
&& buf
->buf
.bytesused
!= 0) {
494 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (FID bit "
496 buf
->state
= UVC_BUF_STATE_READY
;
500 stream
->last_fid
= fid
;
505 static void uvc_video_decode_data(struct uvc_streaming
*stream
,
506 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
508 struct uvc_video_queue
*queue
= &stream
->queue
;
509 unsigned int maxlen
, nbytes
;
515 /* Copy the video data to the buffer. */
516 maxlen
= buf
->buf
.length
- buf
->buf
.bytesused
;
517 mem
= queue
->mem
+ buf
->buf
.m
.offset
+ buf
->buf
.bytesused
;
518 nbytes
= min((unsigned int)len
, maxlen
);
519 memcpy(mem
, data
, nbytes
);
520 buf
->buf
.bytesused
+= nbytes
;
522 /* Complete the current frame if the buffer size was exceeded. */
524 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (overflow).\n");
525 buf
->state
= UVC_BUF_STATE_READY
;
529 static void uvc_video_decode_end(struct uvc_streaming
*stream
,
530 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
532 /* Mark the buffer as done if the EOF marker is set. */
533 if (data
[1] & UVC_STREAM_EOF
&& buf
->buf
.bytesused
!= 0) {
534 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (EOF found).\n");
536 uvc_trace(UVC_TRACE_FRAME
, "EOF in empty payload.\n");
537 buf
->state
= UVC_BUF_STATE_READY
;
538 if (stream
->dev
->quirks
& UVC_QUIRK_STREAM_NO_FID
)
539 stream
->last_fid
^= UVC_STREAM_FID
;
543 /* Video payload encoding is handled by uvc_video_encode_header() and
544 * uvc_video_encode_data(). Only bulk transfers are currently supported.
546 * uvc_video_encode_header is called at the start of a payload. It adds header
547 * data to the transfer buffer and returns the header size. As the only known
548 * UVC output device transfers a whole frame in a single payload, the EOF bit
549 * is always set in the header.
551 * uvc_video_encode_data is called for every URB and copies the data from the
552 * video buffer to the transfer buffer.
554 static int uvc_video_encode_header(struct uvc_streaming
*stream
,
555 struct uvc_buffer
*buf
, __u8
*data
, int len
)
557 data
[0] = 2; /* Header length */
558 data
[1] = UVC_STREAM_EOH
| UVC_STREAM_EOF
559 | (stream
->last_fid
& UVC_STREAM_FID
);
563 static int uvc_video_encode_data(struct uvc_streaming
*stream
,
564 struct uvc_buffer
*buf
, __u8
*data
, int len
)
566 struct uvc_video_queue
*queue
= &stream
->queue
;
570 /* Copy video data to the URB buffer. */
571 mem
= queue
->mem
+ buf
->buf
.m
.offset
+ queue
->buf_used
;
572 nbytes
= min((unsigned int)len
, buf
->buf
.bytesused
- queue
->buf_used
);
573 nbytes
= min(stream
->bulk
.max_payload_size
- stream
->bulk
.payload_size
,
575 memcpy(data
, mem
, nbytes
);
577 queue
->buf_used
+= nbytes
;
582 /* ------------------------------------------------------------------------
587 * Completion handler for video URBs.
589 static void uvc_video_decode_isoc(struct urb
*urb
, struct uvc_streaming
*stream
,
590 struct uvc_buffer
*buf
)
595 for (i
= 0; i
< urb
->number_of_packets
; ++i
) {
596 if (urb
->iso_frame_desc
[i
].status
< 0) {
597 uvc_trace(UVC_TRACE_FRAME
, "USB isochronous frame "
598 "lost (%d).\n", urb
->iso_frame_desc
[i
].status
);
599 /* Mark the buffer as faulty. */
605 /* Decode the payload header. */
606 mem
= urb
->transfer_buffer
+ urb
->iso_frame_desc
[i
].offset
;
608 ret
= uvc_video_decode_start(stream
, buf
, mem
,
609 urb
->iso_frame_desc
[i
].actual_length
);
611 buf
= uvc_queue_next_buffer(&stream
->queue
,
613 } while (ret
== -EAGAIN
);
618 /* Decode the payload data. */
619 uvc_video_decode_data(stream
, buf
, mem
+ ret
,
620 urb
->iso_frame_desc
[i
].actual_length
- ret
);
622 /* Process the header again. */
623 uvc_video_decode_end(stream
, buf
, mem
,
624 urb
->iso_frame_desc
[i
].actual_length
);
626 if (buf
->state
== UVC_BUF_STATE_READY
) {
627 if (buf
->buf
.length
!= buf
->buf
.bytesused
&&
628 !(stream
->cur_format
->flags
&
629 UVC_FMT_FLAG_COMPRESSED
))
632 buf
= uvc_queue_next_buffer(&stream
->queue
, buf
);
637 static void uvc_video_decode_bulk(struct urb
*urb
, struct uvc_streaming
*stream
,
638 struct uvc_buffer
*buf
)
643 if (urb
->actual_length
== 0)
646 mem
= urb
->transfer_buffer
;
647 len
= urb
->actual_length
;
648 stream
->bulk
.payload_size
+= len
;
650 /* If the URB is the first of its payload, decode and save the
653 if (stream
->bulk
.header_size
== 0 && !stream
->bulk
.skip_payload
) {
655 ret
= uvc_video_decode_start(stream
, buf
, mem
, len
);
657 buf
= uvc_queue_next_buffer(&stream
->queue
,
659 } while (ret
== -EAGAIN
);
661 /* If an error occurred skip the rest of the payload. */
662 if (ret
< 0 || buf
== NULL
) {
663 stream
->bulk
.skip_payload
= 1;
665 memcpy(stream
->bulk
.header
, mem
, ret
);
666 stream
->bulk
.header_size
= ret
;
673 /* The buffer queue might have been cancelled while a bulk transfer
674 * was in progress, so we can reach here with buf equal to NULL. Make
675 * sure buf is never dereferenced if NULL.
678 /* Process video data. */
679 if (!stream
->bulk
.skip_payload
&& buf
!= NULL
)
680 uvc_video_decode_data(stream
, buf
, mem
, len
);
682 /* Detect the payload end by a URB smaller than the maximum size (or
683 * a payload size equal to the maximum) and process the header again.
685 if (urb
->actual_length
< urb
->transfer_buffer_length
||
686 stream
->bulk
.payload_size
>= stream
->bulk
.max_payload_size
) {
687 if (!stream
->bulk
.skip_payload
&& buf
!= NULL
) {
688 uvc_video_decode_end(stream
, buf
, stream
->bulk
.header
,
689 stream
->bulk
.payload_size
);
690 if (buf
->state
== UVC_BUF_STATE_READY
)
691 buf
= uvc_queue_next_buffer(&stream
->queue
,
695 stream
->bulk
.header_size
= 0;
696 stream
->bulk
.skip_payload
= 0;
697 stream
->bulk
.payload_size
= 0;
701 static void uvc_video_encode_bulk(struct urb
*urb
, struct uvc_streaming
*stream
,
702 struct uvc_buffer
*buf
)
704 u8
*mem
= urb
->transfer_buffer
;
705 int len
= stream
->urb_size
, ret
;
708 urb
->transfer_buffer_length
= 0;
712 /* If the URB is the first of its payload, add the header. */
713 if (stream
->bulk
.header_size
== 0) {
714 ret
= uvc_video_encode_header(stream
, buf
, mem
, len
);
715 stream
->bulk
.header_size
= ret
;
716 stream
->bulk
.payload_size
+= ret
;
721 /* Process video data. */
722 ret
= uvc_video_encode_data(stream
, buf
, mem
, len
);
724 stream
->bulk
.payload_size
+= ret
;
727 if (buf
->buf
.bytesused
== stream
->queue
.buf_used
||
728 stream
->bulk
.payload_size
== stream
->bulk
.max_payload_size
) {
729 if (buf
->buf
.bytesused
== stream
->queue
.buf_used
) {
730 stream
->queue
.buf_used
= 0;
731 buf
->state
= UVC_BUF_STATE_READY
;
732 buf
->buf
.sequence
= ++stream
->sequence
;
733 uvc_queue_next_buffer(&stream
->queue
, buf
);
734 stream
->last_fid
^= UVC_STREAM_FID
;
737 stream
->bulk
.header_size
= 0;
738 stream
->bulk
.payload_size
= 0;
741 urb
->transfer_buffer_length
= stream
->urb_size
- len
;
744 static void uvc_video_complete(struct urb
*urb
)
746 struct uvc_streaming
*stream
= urb
->context
;
747 struct uvc_video_queue
*queue
= &stream
->queue
;
748 struct uvc_buffer
*buf
= NULL
;
752 switch (urb
->status
) {
757 uvc_printk(KERN_WARNING
, "Non-zero status (%d) in video "
758 "completion handler.\n", urb
->status
);
760 case -ENOENT
: /* usb_kill_urb() called. */
764 case -ECONNRESET
: /* usb_unlink_urb() called. */
765 case -ESHUTDOWN
: /* The endpoint is being disabled. */
766 uvc_queue_cancel(queue
, urb
->status
== -ESHUTDOWN
);
770 spin_lock_irqsave(&queue
->irqlock
, flags
);
771 if (!list_empty(&queue
->irqqueue
))
772 buf
= list_first_entry(&queue
->irqqueue
, struct uvc_buffer
,
774 spin_unlock_irqrestore(&queue
->irqlock
, flags
);
776 stream
->decode(urb
, stream
, buf
);
778 if ((ret
= usb_submit_urb(urb
, GFP_ATOMIC
)) < 0) {
779 uvc_printk(KERN_ERR
, "Failed to resubmit video URB (%d).\n",
785 * Free transfer buffers.
787 static void uvc_free_urb_buffers(struct uvc_streaming
*stream
)
791 for (i
= 0; i
< UVC_URBS
; ++i
) {
792 if (stream
->urb_buffer
[i
]) {
793 usb_free_coherent(stream
->dev
->udev
, stream
->urb_size
,
794 stream
->urb_buffer
[i
], stream
->urb_dma
[i
]);
795 stream
->urb_buffer
[i
] = NULL
;
799 stream
->urb_size
= 0;
803 * Allocate transfer buffers. This function can be called with buffers
804 * already allocated when resuming from suspend, in which case it will
805 * return without touching the buffers.
807 * Limit the buffer size to UVC_MAX_PACKETS bulk/isochronous packets. If the
808 * system is too low on memory try successively smaller numbers of packets
809 * until allocation succeeds.
811 * Return the number of allocated packets on success or 0 when out of memory.
813 static int uvc_alloc_urb_buffers(struct uvc_streaming
*stream
,
814 unsigned int size
, unsigned int psize
, gfp_t gfp_flags
)
816 unsigned int npackets
;
819 /* Buffers are already allocated, bail out. */
820 if (stream
->urb_size
)
821 return stream
->urb_size
/ psize
;
823 /* Compute the number of packets. Bulk endpoints might transfer UVC
824 * payloads across multiple URBs.
826 npackets
= DIV_ROUND_UP(size
, psize
);
827 if (npackets
> UVC_MAX_PACKETS
)
828 npackets
= UVC_MAX_PACKETS
;
830 /* Retry allocations until one succeed. */
831 for (; npackets
> 1; npackets
/= 2) {
832 for (i
= 0; i
< UVC_URBS
; ++i
) {
833 stream
->urb_size
= psize
* npackets
;
834 stream
->urb_buffer
[i
] = usb_alloc_coherent(
835 stream
->dev
->udev
, stream
->urb_size
,
836 gfp_flags
| __GFP_NOWARN
, &stream
->urb_dma
[i
]);
837 if (!stream
->urb_buffer
[i
]) {
838 uvc_free_urb_buffers(stream
);
844 uvc_trace(UVC_TRACE_VIDEO
, "Allocated %u URB buffers "
845 "of %ux%u bytes each.\n", UVC_URBS
, npackets
,
851 uvc_trace(UVC_TRACE_VIDEO
, "Failed to allocate URB buffers (%u bytes "
852 "per packet).\n", psize
);
857 * Uninitialize isochronous/bulk URBs and free transfer buffers.
859 static void uvc_uninit_video(struct uvc_streaming
*stream
, int free_buffers
)
864 for (i
= 0; i
< UVC_URBS
; ++i
) {
865 urb
= stream
->urb
[i
];
871 stream
->urb
[i
] = NULL
;
875 uvc_free_urb_buffers(stream
);
879 * Initialize isochronous URBs and allocate transfer buffers. The packet size
880 * is given by the endpoint.
882 static int uvc_init_video_isoc(struct uvc_streaming
*stream
,
883 struct usb_host_endpoint
*ep
, gfp_t gfp_flags
)
886 unsigned int npackets
, i
, j
;
890 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
);
891 psize
= (psize
& 0x07ff) * (1 + ((psize
>> 11) & 3));
892 size
= stream
->ctrl
.dwMaxVideoFrameSize
;
894 npackets
= uvc_alloc_urb_buffers(stream
, size
, psize
, gfp_flags
);
898 size
= npackets
* psize
;
900 for (i
= 0; i
< UVC_URBS
; ++i
) {
901 urb
= usb_alloc_urb(npackets
, gfp_flags
);
903 uvc_uninit_video(stream
, 1);
907 urb
->dev
= stream
->dev
->udev
;
908 urb
->context
= stream
;
909 urb
->pipe
= usb_rcvisocpipe(stream
->dev
->udev
,
910 ep
->desc
.bEndpointAddress
);
911 urb
->transfer_flags
= URB_ISO_ASAP
| URB_NO_TRANSFER_DMA_MAP
;
912 urb
->interval
= ep
->desc
.bInterval
;
913 urb
->transfer_buffer
= stream
->urb_buffer
[i
];
914 urb
->transfer_dma
= stream
->urb_dma
[i
];
915 urb
->complete
= uvc_video_complete
;
916 urb
->number_of_packets
= npackets
;
917 urb
->transfer_buffer_length
= size
;
919 for (j
= 0; j
< npackets
; ++j
) {
920 urb
->iso_frame_desc
[j
].offset
= j
* psize
;
921 urb
->iso_frame_desc
[j
].length
= psize
;
924 stream
->urb
[i
] = urb
;
931 * Initialize bulk URBs and allocate transfer buffers. The packet size is
932 * given by the endpoint.
934 static int uvc_init_video_bulk(struct uvc_streaming
*stream
,
935 struct usb_host_endpoint
*ep
, gfp_t gfp_flags
)
938 unsigned int npackets
, pipe
, i
;
942 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
) & 0x07ff;
943 size
= stream
->ctrl
.dwMaxPayloadTransferSize
;
944 stream
->bulk
.max_payload_size
= size
;
946 npackets
= uvc_alloc_urb_buffers(stream
, size
, psize
, gfp_flags
);
950 size
= npackets
* psize
;
952 if (usb_endpoint_dir_in(&ep
->desc
))
953 pipe
= usb_rcvbulkpipe(stream
->dev
->udev
,
954 ep
->desc
.bEndpointAddress
);
956 pipe
= usb_sndbulkpipe(stream
->dev
->udev
,
957 ep
->desc
.bEndpointAddress
);
959 if (stream
->type
== V4L2_BUF_TYPE_VIDEO_OUTPUT
)
962 for (i
= 0; i
< UVC_URBS
; ++i
) {
963 urb
= usb_alloc_urb(0, gfp_flags
);
965 uvc_uninit_video(stream
, 1);
969 usb_fill_bulk_urb(urb
, stream
->dev
->udev
, pipe
,
970 stream
->urb_buffer
[i
], size
, uvc_video_complete
,
972 urb
->transfer_flags
= URB_NO_TRANSFER_DMA_MAP
;
973 urb
->transfer_dma
= stream
->urb_dma
[i
];
975 stream
->urb
[i
] = urb
;
982 * Initialize isochronous/bulk URBs and allocate transfer buffers.
984 static int uvc_init_video(struct uvc_streaming
*stream
, gfp_t gfp_flags
)
986 struct usb_interface
*intf
= stream
->intf
;
987 struct usb_host_endpoint
*ep
;
991 stream
->sequence
= -1;
992 stream
->last_fid
= -1;
993 stream
->bulk
.header_size
= 0;
994 stream
->bulk
.skip_payload
= 0;
995 stream
->bulk
.payload_size
= 0;
997 if (intf
->num_altsetting
> 1) {
998 struct usb_host_endpoint
*best_ep
= NULL
;
999 unsigned int best_psize
= 3 * 1024;
1000 unsigned int bandwidth
;
1001 unsigned int uninitialized_var(altsetting
);
1002 int intfnum
= stream
->intfnum
;
1004 /* Isochronous endpoint, select the alternate setting. */
1005 bandwidth
= stream
->ctrl
.dwMaxPayloadTransferSize
;
1007 if (bandwidth
== 0) {
1008 uvc_trace(UVC_TRACE_VIDEO
, "Device requested null "
1009 "bandwidth, defaulting to lowest.\n");
1012 uvc_trace(UVC_TRACE_VIDEO
, "Device requested %u "
1013 "B/frame bandwidth.\n", bandwidth
);
1016 for (i
= 0; i
< intf
->num_altsetting
; ++i
) {
1017 struct usb_host_interface
*alts
;
1020 alts
= &intf
->altsetting
[i
];
1021 ep
= uvc_find_endpoint(alts
,
1022 stream
->header
.bEndpointAddress
);
1026 /* Check if the bandwidth is high enough. */
1027 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
);
1028 psize
= (psize
& 0x07ff) * (1 + ((psize
>> 11) & 3));
1029 if (psize
>= bandwidth
&& psize
<= best_psize
) {
1036 if (best_ep
== NULL
) {
1037 uvc_trace(UVC_TRACE_VIDEO
, "No fast enough alt setting "
1038 "for requested bandwidth.\n");
1042 uvc_trace(UVC_TRACE_VIDEO
, "Selecting alternate setting %u "
1043 "(%u B/frame bandwidth).\n", altsetting
, best_psize
);
1045 ret
= usb_set_interface(stream
->dev
->udev
, intfnum
, altsetting
);
1049 ret
= uvc_init_video_isoc(stream
, best_ep
, gfp_flags
);
1051 /* Bulk endpoint, proceed to URB initialization. */
1052 ep
= uvc_find_endpoint(&intf
->altsetting
[0],
1053 stream
->header
.bEndpointAddress
);
1057 ret
= uvc_init_video_bulk(stream
, ep
, gfp_flags
);
1063 /* Submit the URBs. */
1064 for (i
= 0; i
< UVC_URBS
; ++i
) {
1065 ret
= usb_submit_urb(stream
->urb
[i
], gfp_flags
);
1067 uvc_printk(KERN_ERR
, "Failed to submit URB %u "
1069 uvc_uninit_video(stream
, 1);
1077 /* --------------------------------------------------------------------------
1082 * Stop streaming without disabling the video queue.
1084 * To let userspace applications resume without trouble, we must not touch the
1085 * video buffers in any way. We mark the device as frozen to make sure the URB
1086 * completion handler won't try to cancel the queue when we kill the URBs.
1088 int uvc_video_suspend(struct uvc_streaming
*stream
)
1090 if (!uvc_queue_streaming(&stream
->queue
))
1094 uvc_uninit_video(stream
, 0);
1095 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1100 * Reconfigure the video interface and restart streaming if it was enabled
1103 * If an error occurs, disable the video queue. This will wake all pending
1104 * buffers, making sure userspace applications are notified of the problem
1105 * instead of waiting forever.
1107 int uvc_video_resume(struct uvc_streaming
*stream
)
1113 ret
= uvc_commit_video(stream
, &stream
->ctrl
);
1115 uvc_queue_enable(&stream
->queue
, 0);
1119 if (!uvc_queue_streaming(&stream
->queue
))
1122 ret
= uvc_init_video(stream
, GFP_NOIO
);
1124 uvc_queue_enable(&stream
->queue
, 0);
1129 /* ------------------------------------------------------------------------
1134 * Initialize the UVC video device by switching to alternate setting 0 and
1135 * retrieve the default format.
1137 * Some cameras (namely the Fuji Finepix) set the format and frame
1138 * indexes to zero. The UVC standard doesn't clearly make this a spec
1139 * violation, so try to silently fix the values if possible.
1141 * This function is called before registering the device with V4L.
1143 int uvc_video_init(struct uvc_streaming
*stream
)
1145 struct uvc_streaming_control
*probe
= &stream
->ctrl
;
1146 struct uvc_format
*format
= NULL
;
1147 struct uvc_frame
*frame
= NULL
;
1151 if (stream
->nformats
== 0) {
1152 uvc_printk(KERN_INFO
, "No supported video formats found.\n");
1156 atomic_set(&stream
->active
, 0);
1158 /* Initialize the video buffers queue. */
1159 uvc_queue_init(&stream
->queue
, stream
->type
, !uvc_no_drop_param
);
1161 /* Alternate setting 0 should be the default, yet the XBox Live Vision
1162 * Cam (and possibly other devices) crash or otherwise misbehave if
1163 * they don't receive a SET_INTERFACE request before any other video
1166 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1168 /* Set the streaming probe control with default streaming parameters
1169 * retrieved from the device. Webcams that don't suport GET_DEF
1170 * requests on the probe control will just keep their current streaming
1173 if (uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_DEF
) == 0)
1174 uvc_set_video_ctrl(stream
, probe
, 1);
1176 /* Initialize the streaming parameters with the probe control current
1177 * value. This makes sure SET_CUR requests on the streaming commit
1178 * control will always use values retrieved from a successful GET_CUR
1179 * request on the probe control, as required by the UVC specification.
1181 ret
= uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_CUR
);
1185 /* Check if the default format descriptor exists. Use the first
1186 * available format otherwise.
1188 for (i
= stream
->nformats
; i
> 0; --i
) {
1189 format
= &stream
->format
[i
-1];
1190 if (format
->index
== probe
->bFormatIndex
)
1194 if (format
->nframes
== 0) {
1195 uvc_printk(KERN_INFO
, "No frame descriptor found for the "
1196 "default format.\n");
1200 /* Zero bFrameIndex might be correct. Stream-based formats (including
1201 * MPEG-2 TS and DV) do not support frames but have a dummy frame
1202 * descriptor with bFrameIndex set to zero. If the default frame
1203 * descriptor is not found, use the first available frame.
1205 for (i
= format
->nframes
; i
> 0; --i
) {
1206 frame
= &format
->frame
[i
-1];
1207 if (frame
->bFrameIndex
== probe
->bFrameIndex
)
1211 probe
->bFormatIndex
= format
->index
;
1212 probe
->bFrameIndex
= frame
->bFrameIndex
;
1214 stream
->cur_format
= format
;
1215 stream
->cur_frame
= frame
;
1217 /* Select the video decoding function */
1218 if (stream
->type
== V4L2_BUF_TYPE_VIDEO_CAPTURE
) {
1219 if (stream
->dev
->quirks
& UVC_QUIRK_BUILTIN_ISIGHT
)
1220 stream
->decode
= uvc_video_decode_isight
;
1221 else if (stream
->intf
->num_altsetting
> 1)
1222 stream
->decode
= uvc_video_decode_isoc
;
1224 stream
->decode
= uvc_video_decode_bulk
;
1226 if (stream
->intf
->num_altsetting
== 1)
1227 stream
->decode
= uvc_video_encode_bulk
;
1229 uvc_printk(KERN_INFO
, "Isochronous endpoints are not "
1230 "supported for video output devices.\n");
1239 * Enable or disable the video stream.
1241 int uvc_video_enable(struct uvc_streaming
*stream
, int enable
)
1246 uvc_uninit_video(stream
, 1);
1247 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1248 uvc_queue_enable(&stream
->queue
, 0);
1252 ret
= uvc_queue_enable(&stream
->queue
, 1);
1256 /* Commit the streaming parameters. */
1257 ret
= uvc_commit_video(stream
, &stream
->ctrl
);
1259 uvc_queue_enable(&stream
->queue
, 0);
1263 return uvc_init_video(stream
, GFP_KERNEL
);