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 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
;
93 struct uvc_frame
*frame
= NULL
;
96 if (ctrl
->bFormatIndex
<= 0 ||
97 ctrl
->bFormatIndex
> stream
->nformats
)
100 format
= &stream
->format
[ctrl
->bFormatIndex
- 1];
102 for (i
= 0; i
< format
->nframes
; ++i
) {
103 if (format
->frame
[i
].bFrameIndex
== ctrl
->bFrameIndex
) {
104 frame
= &format
->frame
[i
];
112 if (!(format
->flags
& UVC_FMT_FLAG_COMPRESSED
) ||
113 (ctrl
->dwMaxVideoFrameSize
== 0 &&
114 stream
->dev
->uvc_version
< 0x0110))
115 ctrl
->dwMaxVideoFrameSize
=
116 frame
->dwMaxVideoFrameBufferSize
;
118 if (!(format
->flags
& UVC_FMT_FLAG_COMPRESSED
) &&
119 stream
->dev
->quirks
& UVC_QUIRK_FIX_BANDWIDTH
&&
120 stream
->intf
->num_altsetting
> 1) {
124 interval
= (ctrl
->dwFrameInterval
> 100000)
125 ? ctrl
->dwFrameInterval
126 : frame
->dwFrameInterval
[0];
128 /* Compute a bandwidth estimation by multiplying the frame
129 * size by the number of video frames per second, divide the
130 * result by the number of USB frames (or micro-frames for
131 * high-speed devices) per second and add the UVC header size
132 * (assumed to be 12 bytes long).
134 bandwidth
= frame
->wWidth
* frame
->wHeight
/ 8 * format
->bpp
;
135 bandwidth
*= 10000000 / interval
+ 1;
137 if (stream
->dev
->udev
->speed
== USB_SPEED_HIGH
)
141 ctrl
->dwMaxPayloadTransferSize
= bandwidth
;
145 static int uvc_get_video_ctrl(struct uvc_streaming
*stream
,
146 struct uvc_streaming_control
*ctrl
, int probe
, __u8 query
)
152 size
= stream
->dev
->uvc_version
>= 0x0110 ? 34 : 26;
153 if ((stream
->dev
->quirks
& UVC_QUIRK_PROBE_DEF
) &&
154 query
== UVC_GET_DEF
)
157 data
= kmalloc(size
, GFP_KERNEL
);
161 ret
= __uvc_query_ctrl(stream
->dev
, query
, 0, stream
->intfnum
,
162 probe
? UVC_VS_PROBE_CONTROL
: UVC_VS_COMMIT_CONTROL
, data
,
163 size
, uvc_timeout_param
);
165 if ((query
== UVC_GET_MIN
|| query
== UVC_GET_MAX
) && ret
== 2) {
166 /* Some cameras, mostly based on Bison Electronics chipsets,
167 * answer a GET_MIN or GET_MAX request with the wCompQuality
170 uvc_warn_once(stream
->dev
, UVC_WARN_MINMAX
, "UVC non "
171 "compliance - GET_MIN/MAX(PROBE) incorrectly "
172 "supported. Enabling workaround.\n");
173 memset(ctrl
, 0, sizeof *ctrl
);
174 ctrl
->wCompQuality
= le16_to_cpup((__le16
*)data
);
177 } else if (query
== UVC_GET_DEF
&& probe
== 1 && ret
!= size
) {
178 /* Many cameras don't support the GET_DEF request on their
179 * video probe control. Warn once and return, the caller will
180 * fall back to GET_CUR.
182 uvc_warn_once(stream
->dev
, UVC_WARN_PROBE_DEF
, "UVC non "
183 "compliance - GET_DEF(PROBE) not supported. "
184 "Enabling workaround.\n");
187 } else if (ret
!= size
) {
188 uvc_printk(KERN_ERR
, "Failed to query (%u) UVC %s control : "
189 "%d (exp. %u).\n", query
, probe
? "probe" : "commit",
195 ctrl
->bmHint
= le16_to_cpup((__le16
*)&data
[0]);
196 ctrl
->bFormatIndex
= data
[2];
197 ctrl
->bFrameIndex
= data
[3];
198 ctrl
->dwFrameInterval
= le32_to_cpup((__le32
*)&data
[4]);
199 ctrl
->wKeyFrameRate
= le16_to_cpup((__le16
*)&data
[8]);
200 ctrl
->wPFrameRate
= le16_to_cpup((__le16
*)&data
[10]);
201 ctrl
->wCompQuality
= le16_to_cpup((__le16
*)&data
[12]);
202 ctrl
->wCompWindowSize
= le16_to_cpup((__le16
*)&data
[14]);
203 ctrl
->wDelay
= le16_to_cpup((__le16
*)&data
[16]);
204 ctrl
->dwMaxVideoFrameSize
= get_unaligned_le32(&data
[18]);
205 ctrl
->dwMaxPayloadTransferSize
= get_unaligned_le32(&data
[22]);
208 ctrl
->dwClockFrequency
= get_unaligned_le32(&data
[26]);
209 ctrl
->bmFramingInfo
= data
[30];
210 ctrl
->bPreferedVersion
= data
[31];
211 ctrl
->bMinVersion
= data
[32];
212 ctrl
->bMaxVersion
= data
[33];
214 ctrl
->dwClockFrequency
= stream
->dev
->clock_frequency
;
215 ctrl
->bmFramingInfo
= 0;
216 ctrl
->bPreferedVersion
= 0;
217 ctrl
->bMinVersion
= 0;
218 ctrl
->bMaxVersion
= 0;
221 /* Some broken devices return null or wrong dwMaxVideoFrameSize and
222 * dwMaxPayloadTransferSize fields. Try to get the value from the
223 * format and frame descriptors.
225 uvc_fixup_video_ctrl(stream
, ctrl
);
233 static int uvc_set_video_ctrl(struct uvc_streaming
*stream
,
234 struct uvc_streaming_control
*ctrl
, int probe
)
240 size
= stream
->dev
->uvc_version
>= 0x0110 ? 34 : 26;
241 data
= kzalloc(size
, GFP_KERNEL
);
245 *(__le16
*)&data
[0] = cpu_to_le16(ctrl
->bmHint
);
246 data
[2] = ctrl
->bFormatIndex
;
247 data
[3] = ctrl
->bFrameIndex
;
248 *(__le32
*)&data
[4] = cpu_to_le32(ctrl
->dwFrameInterval
);
249 *(__le16
*)&data
[8] = cpu_to_le16(ctrl
->wKeyFrameRate
);
250 *(__le16
*)&data
[10] = cpu_to_le16(ctrl
->wPFrameRate
);
251 *(__le16
*)&data
[12] = cpu_to_le16(ctrl
->wCompQuality
);
252 *(__le16
*)&data
[14] = cpu_to_le16(ctrl
->wCompWindowSize
);
253 *(__le16
*)&data
[16] = cpu_to_le16(ctrl
->wDelay
);
254 put_unaligned_le32(ctrl
->dwMaxVideoFrameSize
, &data
[18]);
255 put_unaligned_le32(ctrl
->dwMaxPayloadTransferSize
, &data
[22]);
258 put_unaligned_le32(ctrl
->dwClockFrequency
, &data
[26]);
259 data
[30] = ctrl
->bmFramingInfo
;
260 data
[31] = ctrl
->bPreferedVersion
;
261 data
[32] = ctrl
->bMinVersion
;
262 data
[33] = ctrl
->bMaxVersion
;
265 ret
= __uvc_query_ctrl(stream
->dev
, UVC_SET_CUR
, 0, stream
->intfnum
,
266 probe
? UVC_VS_PROBE_CONTROL
: UVC_VS_COMMIT_CONTROL
, data
,
267 size
, uvc_timeout_param
);
269 uvc_printk(KERN_ERR
, "Failed to set UVC %s control : "
270 "%d (exp. %u).\n", probe
? "probe" : "commit",
279 int uvc_probe_video(struct uvc_streaming
*stream
,
280 struct uvc_streaming_control
*probe
)
282 struct uvc_streaming_control probe_min
, probe_max
;
287 mutex_lock(&stream
->mutex
);
289 /* Perform probing. The device should adjust the requested values
290 * according to its capabilities. However, some devices, namely the
291 * first generation UVC Logitech webcams, don't implement the Video
292 * Probe control properly, and just return the needed bandwidth. For
293 * that reason, if the needed bandwidth exceeds the maximum available
294 * bandwidth, try to lower the quality.
296 ret
= uvc_set_video_ctrl(stream
, probe
, 1);
300 /* Get the minimum and maximum values for compression settings. */
301 if (!(stream
->dev
->quirks
& UVC_QUIRK_PROBE_MINMAX
)) {
302 ret
= uvc_get_video_ctrl(stream
, &probe_min
, 1, UVC_GET_MIN
);
305 ret
= uvc_get_video_ctrl(stream
, &probe_max
, 1, UVC_GET_MAX
);
309 probe
->wCompQuality
= probe_max
.wCompQuality
;
312 for (i
= 0; i
< 2; ++i
) {
313 ret
= uvc_set_video_ctrl(stream
, probe
, 1);
316 ret
= uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_CUR
);
320 if (stream
->intf
->num_altsetting
== 1)
323 bandwidth
= probe
->dwMaxPayloadTransferSize
;
324 if (bandwidth
<= stream
->maxpsize
)
327 if (stream
->dev
->quirks
& UVC_QUIRK_PROBE_MINMAX
) {
332 /* TODO: negotiate compression parameters */
333 probe
->wKeyFrameRate
= probe_min
.wKeyFrameRate
;
334 probe
->wPFrameRate
= probe_min
.wPFrameRate
;
335 probe
->wCompQuality
= probe_max
.wCompQuality
;
336 probe
->wCompWindowSize
= probe_min
.wCompWindowSize
;
340 mutex_unlock(&stream
->mutex
);
344 int uvc_commit_video(struct uvc_streaming
*stream
,
345 struct uvc_streaming_control
*probe
)
347 return uvc_set_video_ctrl(stream
, probe
, 0);
350 /* ------------------------------------------------------------------------
354 /* Values for bmHeaderInfo (Video and Still Image Payload Headers, 2.4.3.3) */
355 #define UVC_STREAM_EOH (1 << 7)
356 #define UVC_STREAM_ERR (1 << 6)
357 #define UVC_STREAM_STI (1 << 5)
358 #define UVC_STREAM_RES (1 << 4)
359 #define UVC_STREAM_SCR (1 << 3)
360 #define UVC_STREAM_PTS (1 << 2)
361 #define UVC_STREAM_EOF (1 << 1)
362 #define UVC_STREAM_FID (1 << 0)
364 /* Video payload decoding is handled by uvc_video_decode_start(),
365 * uvc_video_decode_data() and uvc_video_decode_end().
367 * uvc_video_decode_start is called with URB data at the start of a bulk or
368 * isochronous payload. It processes header data and returns the header size
369 * in bytes if successful. If an error occurs, it returns a negative error
370 * code. The following error codes have special meanings.
372 * - EAGAIN informs the caller that the current video buffer should be marked
373 * as done, and that the function should be called again with the same data
374 * and a new video buffer. This is used when end of frame conditions can be
375 * reliably detected at the beginning of the next frame only.
377 * If an error other than -EAGAIN is returned, the caller will drop the current
378 * payload. No call to uvc_video_decode_data and uvc_video_decode_end will be
379 * made until the next payload. -ENODATA can be used to drop the current
380 * payload if no other error code is appropriate.
382 * uvc_video_decode_data is called for every URB with URB data. It copies the
383 * data to the video buffer.
385 * uvc_video_decode_end is called with header data at the end of a bulk or
386 * isochronous payload. It performs any additional header data processing and
387 * returns 0 or a negative error code if an error occured. As header data have
388 * already been processed by uvc_video_decode_start, this functions isn't
389 * required to perform sanity checks a second time.
391 * For isochronous transfers where a payload is always transfered in a single
392 * URB, the three functions will be called in a row.
394 * To let the decoder process header data and update its internal state even
395 * when no video buffer is available, uvc_video_decode_start must be prepared
396 * to be called with a NULL buf parameter. uvc_video_decode_data and
397 * uvc_video_decode_end will never be called with a NULL buffer.
399 static int uvc_video_decode_start(struct uvc_streaming
*stream
,
400 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
405 * - packet must be at least 2 bytes long
406 * - bHeaderLength value must be at least 2 bytes (see above)
407 * - bHeaderLength value can't be larger than the packet size.
409 if (len
< 2 || data
[0] < 2 || data
[0] > len
)
412 /* Skip payloads marked with the error bit ("error frames"). */
413 if (data
[1] & UVC_STREAM_ERR
) {
414 uvc_trace(UVC_TRACE_FRAME
, "Dropping payload (error bit "
419 fid
= data
[1] & UVC_STREAM_FID
;
421 /* Store the payload FID bit and return immediately when the buffer is
425 stream
->last_fid
= fid
;
429 /* Synchronize to the input stream by waiting for the FID bit to be
430 * toggled when the the buffer state is not UVC_BUF_STATE_ACTIVE.
431 * stream->last_fid is initialized to -1, so the first isochronous
432 * frame will always be in sync.
434 * If the device doesn't toggle the FID bit, invert stream->last_fid
435 * when the EOF bit is set to force synchronisation on the next packet.
437 if (buf
->state
!= UVC_BUF_STATE_ACTIVE
) {
440 if (fid
== stream
->last_fid
) {
441 uvc_trace(UVC_TRACE_FRAME
, "Dropping payload (out of "
443 if ((stream
->dev
->quirks
& UVC_QUIRK_STREAM_NO_FID
) &&
444 (data
[1] & UVC_STREAM_EOF
))
445 stream
->last_fid
^= UVC_STREAM_FID
;
449 if (uvc_clock_param
== CLOCK_MONOTONIC
)
452 ktime_get_real_ts(&ts
);
454 buf
->buf
.timestamp
.tv_sec
= ts
.tv_sec
;
455 buf
->buf
.timestamp
.tv_usec
= ts
.tv_nsec
/ NSEC_PER_USEC
;
457 /* TODO: Handle PTS and SCR. */
458 buf
->state
= UVC_BUF_STATE_ACTIVE
;
461 /* Mark the buffer as done if we're at the beginning of a new frame.
462 * End of frame detection is better implemented by checking the EOF
463 * bit (FID bit toggling is delayed by one frame compared to the EOF
464 * bit), but some devices don't set the bit at end of frame (and the
465 * last payload can be lost anyway). We thus must check if the FID has
468 * stream->last_fid is initialized to -1, so the first isochronous
469 * frame will never trigger an end of frame detection.
471 * Empty buffers (bytesused == 0) don't trigger end of frame detection
472 * as it doesn't make sense to return an empty buffer. This also
473 * avoids detecting end of frame conditions at FID toggling if the
474 * previous payload had the EOF bit set.
476 if (fid
!= stream
->last_fid
&& buf
->buf
.bytesused
!= 0) {
477 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (FID bit "
479 buf
->state
= UVC_BUF_STATE_READY
;
483 stream
->last_fid
= fid
;
488 static void uvc_video_decode_data(struct uvc_streaming
*stream
,
489 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
491 struct uvc_video_queue
*queue
= &stream
->queue
;
492 unsigned int maxlen
, nbytes
;
498 /* Copy the video data to the buffer. */
499 maxlen
= buf
->buf
.length
- buf
->buf
.bytesused
;
500 mem
= queue
->mem
+ buf
->buf
.m
.offset
+ buf
->buf
.bytesused
;
501 nbytes
= min((unsigned int)len
, maxlen
);
502 memcpy(mem
, data
, nbytes
);
503 buf
->buf
.bytesused
+= nbytes
;
505 /* Complete the current frame if the buffer size was exceeded. */
507 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (overflow).\n");
508 buf
->state
= UVC_BUF_STATE_READY
;
512 static void uvc_video_decode_end(struct uvc_streaming
*stream
,
513 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
515 /* Mark the buffer as done if the EOF marker is set. */
516 if (data
[1] & UVC_STREAM_EOF
&& buf
->buf
.bytesused
!= 0) {
517 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (EOF found).\n");
519 uvc_trace(UVC_TRACE_FRAME
, "EOF in empty payload.\n");
520 buf
->state
= UVC_BUF_STATE_READY
;
521 if (stream
->dev
->quirks
& UVC_QUIRK_STREAM_NO_FID
)
522 stream
->last_fid
^= UVC_STREAM_FID
;
526 /* Video payload encoding is handled by uvc_video_encode_header() and
527 * uvc_video_encode_data(). Only bulk transfers are currently supported.
529 * uvc_video_encode_header is called at the start of a payload. It adds header
530 * data to the transfer buffer and returns the header size. As the only known
531 * UVC output device transfers a whole frame in a single payload, the EOF bit
532 * is always set in the header.
534 * uvc_video_encode_data is called for every URB and copies the data from the
535 * video buffer to the transfer buffer.
537 static int uvc_video_encode_header(struct uvc_streaming
*stream
,
538 struct uvc_buffer
*buf
, __u8
*data
, int len
)
540 data
[0] = 2; /* Header length */
541 data
[1] = UVC_STREAM_EOH
| UVC_STREAM_EOF
542 | (stream
->last_fid
& UVC_STREAM_FID
);
546 static int uvc_video_encode_data(struct uvc_streaming
*stream
,
547 struct uvc_buffer
*buf
, __u8
*data
, int len
)
549 struct uvc_video_queue
*queue
= &stream
->queue
;
553 /* Copy video data to the URB buffer. */
554 mem
= queue
->mem
+ buf
->buf
.m
.offset
+ queue
->buf_used
;
555 nbytes
= min((unsigned int)len
, buf
->buf
.bytesused
- queue
->buf_used
);
556 nbytes
= min(stream
->bulk
.max_payload_size
- stream
->bulk
.payload_size
,
558 memcpy(data
, mem
, nbytes
);
560 queue
->buf_used
+= nbytes
;
565 /* ------------------------------------------------------------------------
570 * Completion handler for video URBs.
572 static void uvc_video_decode_isoc(struct urb
*urb
, struct uvc_streaming
*stream
,
573 struct uvc_buffer
*buf
)
578 for (i
= 0; i
< urb
->number_of_packets
; ++i
) {
579 if (urb
->iso_frame_desc
[i
].status
< 0) {
580 uvc_trace(UVC_TRACE_FRAME
, "USB isochronous frame "
581 "lost (%d).\n", urb
->iso_frame_desc
[i
].status
);
582 /* Mark the buffer as faulty. */
588 /* Decode the payload header. */
589 mem
= urb
->transfer_buffer
+ urb
->iso_frame_desc
[i
].offset
;
591 ret
= uvc_video_decode_start(stream
, buf
, mem
,
592 urb
->iso_frame_desc
[i
].actual_length
);
594 buf
= uvc_queue_next_buffer(&stream
->queue
,
596 } while (ret
== -EAGAIN
);
601 /* Decode the payload data. */
602 uvc_video_decode_data(stream
, buf
, mem
+ ret
,
603 urb
->iso_frame_desc
[i
].actual_length
- ret
);
605 /* Process the header again. */
606 uvc_video_decode_end(stream
, buf
, mem
,
607 urb
->iso_frame_desc
[i
].actual_length
);
609 if (buf
->state
== UVC_BUF_STATE_READY
) {
610 if (buf
->buf
.length
!= buf
->buf
.bytesused
&&
611 !(stream
->cur_format
->flags
&
612 UVC_FMT_FLAG_COMPRESSED
))
615 buf
= uvc_queue_next_buffer(&stream
->queue
, buf
);
620 static void uvc_video_decode_bulk(struct urb
*urb
, struct uvc_streaming
*stream
,
621 struct uvc_buffer
*buf
)
626 if (urb
->actual_length
== 0)
629 mem
= urb
->transfer_buffer
;
630 len
= urb
->actual_length
;
631 stream
->bulk
.payload_size
+= len
;
633 /* If the URB is the first of its payload, decode and save the
636 if (stream
->bulk
.header_size
== 0 && !stream
->bulk
.skip_payload
) {
638 ret
= uvc_video_decode_start(stream
, buf
, mem
, len
);
640 buf
= uvc_queue_next_buffer(&stream
->queue
,
642 } while (ret
== -EAGAIN
);
644 /* If an error occured skip the rest of the payload. */
645 if (ret
< 0 || buf
== NULL
) {
646 stream
->bulk
.skip_payload
= 1;
648 memcpy(stream
->bulk
.header
, mem
, ret
);
649 stream
->bulk
.header_size
= ret
;
656 /* The buffer queue might have been cancelled while a bulk transfer
657 * was in progress, so we can reach here with buf equal to NULL. Make
658 * sure buf is never dereferenced if NULL.
661 /* Process video data. */
662 if (!stream
->bulk
.skip_payload
&& buf
!= NULL
)
663 uvc_video_decode_data(stream
, buf
, mem
, len
);
665 /* Detect the payload end by a URB smaller than the maximum size (or
666 * a payload size equal to the maximum) and process the header again.
668 if (urb
->actual_length
< urb
->transfer_buffer_length
||
669 stream
->bulk
.payload_size
>= stream
->bulk
.max_payload_size
) {
670 if (!stream
->bulk
.skip_payload
&& buf
!= NULL
) {
671 uvc_video_decode_end(stream
, buf
, stream
->bulk
.header
,
672 stream
->bulk
.payload_size
);
673 if (buf
->state
== UVC_BUF_STATE_READY
)
674 buf
= uvc_queue_next_buffer(&stream
->queue
,
678 stream
->bulk
.header_size
= 0;
679 stream
->bulk
.skip_payload
= 0;
680 stream
->bulk
.payload_size
= 0;
684 static void uvc_video_encode_bulk(struct urb
*urb
, struct uvc_streaming
*stream
,
685 struct uvc_buffer
*buf
)
687 u8
*mem
= urb
->transfer_buffer
;
688 int len
= stream
->urb_size
, ret
;
691 urb
->transfer_buffer_length
= 0;
695 /* If the URB is the first of its payload, add the header. */
696 if (stream
->bulk
.header_size
== 0) {
697 ret
= uvc_video_encode_header(stream
, buf
, mem
, len
);
698 stream
->bulk
.header_size
= ret
;
699 stream
->bulk
.payload_size
+= ret
;
704 /* Process video data. */
705 ret
= uvc_video_encode_data(stream
, buf
, mem
, len
);
707 stream
->bulk
.payload_size
+= ret
;
710 if (buf
->buf
.bytesused
== stream
->queue
.buf_used
||
711 stream
->bulk
.payload_size
== stream
->bulk
.max_payload_size
) {
712 if (buf
->buf
.bytesused
== stream
->queue
.buf_used
) {
713 stream
->queue
.buf_used
= 0;
714 buf
->state
= UVC_BUF_STATE_READY
;
715 uvc_queue_next_buffer(&stream
->queue
, buf
);
716 stream
->last_fid
^= UVC_STREAM_FID
;
719 stream
->bulk
.header_size
= 0;
720 stream
->bulk
.payload_size
= 0;
723 urb
->transfer_buffer_length
= stream
->urb_size
- len
;
726 static void uvc_video_complete(struct urb
*urb
)
728 struct uvc_streaming
*stream
= urb
->context
;
729 struct uvc_video_queue
*queue
= &stream
->queue
;
730 struct uvc_buffer
*buf
= NULL
;
734 switch (urb
->status
) {
739 uvc_printk(KERN_WARNING
, "Non-zero status (%d) in video "
740 "completion handler.\n", urb
->status
);
742 case -ENOENT
: /* usb_kill_urb() called. */
746 case -ECONNRESET
: /* usb_unlink_urb() called. */
747 case -ESHUTDOWN
: /* The endpoint is being disabled. */
748 uvc_queue_cancel(queue
, urb
->status
== -ESHUTDOWN
);
752 spin_lock_irqsave(&queue
->irqlock
, flags
);
753 if (!list_empty(&queue
->irqqueue
))
754 buf
= list_first_entry(&queue
->irqqueue
, struct uvc_buffer
,
756 spin_unlock_irqrestore(&queue
->irqlock
, flags
);
758 stream
->decode(urb
, stream
, buf
);
760 if ((ret
= usb_submit_urb(urb
, GFP_ATOMIC
)) < 0) {
761 uvc_printk(KERN_ERR
, "Failed to resubmit video URB (%d).\n",
767 * Free transfer buffers.
769 static void uvc_free_urb_buffers(struct uvc_streaming
*stream
)
773 for (i
= 0; i
< UVC_URBS
; ++i
) {
774 if (stream
->urb_buffer
[i
]) {
775 usb_free_coherent(stream
->dev
->udev
, stream
->urb_size
,
776 stream
->urb_buffer
[i
], stream
->urb_dma
[i
]);
777 stream
->urb_buffer
[i
] = NULL
;
781 stream
->urb_size
= 0;
785 * Allocate transfer buffers. This function can be called with buffers
786 * already allocated when resuming from suspend, in which case it will
787 * return without touching the buffers.
789 * Limit the buffer size to UVC_MAX_PACKETS bulk/isochronous packets. If the
790 * system is too low on memory try successively smaller numbers of packets
791 * until allocation succeeds.
793 * Return the number of allocated packets on success or 0 when out of memory.
795 static int uvc_alloc_urb_buffers(struct uvc_streaming
*stream
,
796 unsigned int size
, unsigned int psize
, gfp_t gfp_flags
)
798 unsigned int npackets
;
801 /* Buffers are already allocated, bail out. */
802 if (stream
->urb_size
)
803 return stream
->urb_size
/ psize
;
805 /* Compute the number of packets. Bulk endpoints might transfer UVC
806 * payloads accross multiple URBs.
808 npackets
= DIV_ROUND_UP(size
, psize
);
809 if (npackets
> UVC_MAX_PACKETS
)
810 npackets
= UVC_MAX_PACKETS
;
812 /* Retry allocations until one succeed. */
813 for (; npackets
> 1; npackets
/= 2) {
814 for (i
= 0; i
< UVC_URBS
; ++i
) {
815 stream
->urb_size
= psize
* npackets
;
816 stream
->urb_buffer
[i
] = usb_alloc_coherent(
817 stream
->dev
->udev
, stream
->urb_size
,
818 gfp_flags
| __GFP_NOWARN
, &stream
->urb_dma
[i
]);
819 if (!stream
->urb_buffer
[i
]) {
820 uvc_free_urb_buffers(stream
);
826 uvc_trace(UVC_TRACE_VIDEO
, "Allocated %u URB buffers "
827 "of %ux%u bytes each.\n", UVC_URBS
, npackets
,
833 uvc_trace(UVC_TRACE_VIDEO
, "Failed to allocate URB buffers (%u bytes "
834 "per packet).\n", psize
);
839 * Uninitialize isochronous/bulk URBs and free transfer buffers.
841 static void uvc_uninit_video(struct uvc_streaming
*stream
, int free_buffers
)
846 for (i
= 0; i
< UVC_URBS
; ++i
) {
847 urb
= stream
->urb
[i
];
853 stream
->urb
[i
] = NULL
;
857 uvc_free_urb_buffers(stream
);
861 * Initialize isochronous URBs and allocate transfer buffers. The packet size
862 * is given by the endpoint.
864 static int uvc_init_video_isoc(struct uvc_streaming
*stream
,
865 struct usb_host_endpoint
*ep
, gfp_t gfp_flags
)
868 unsigned int npackets
, i
, j
;
872 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
);
873 psize
= (psize
& 0x07ff) * (1 + ((psize
>> 11) & 3));
874 size
= stream
->ctrl
.dwMaxVideoFrameSize
;
876 npackets
= uvc_alloc_urb_buffers(stream
, size
, psize
, gfp_flags
);
880 size
= npackets
* psize
;
882 for (i
= 0; i
< UVC_URBS
; ++i
) {
883 urb
= usb_alloc_urb(npackets
, gfp_flags
);
885 uvc_uninit_video(stream
, 1);
889 urb
->dev
= stream
->dev
->udev
;
890 urb
->context
= stream
;
891 urb
->pipe
= usb_rcvisocpipe(stream
->dev
->udev
,
892 ep
->desc
.bEndpointAddress
);
893 urb
->transfer_flags
= URB_ISO_ASAP
| URB_NO_TRANSFER_DMA_MAP
;
894 urb
->interval
= ep
->desc
.bInterval
;
895 urb
->transfer_buffer
= stream
->urb_buffer
[i
];
896 urb
->transfer_dma
= stream
->urb_dma
[i
];
897 urb
->complete
= uvc_video_complete
;
898 urb
->number_of_packets
= npackets
;
899 urb
->transfer_buffer_length
= size
;
901 for (j
= 0; j
< npackets
; ++j
) {
902 urb
->iso_frame_desc
[j
].offset
= j
* psize
;
903 urb
->iso_frame_desc
[j
].length
= psize
;
906 stream
->urb
[i
] = urb
;
913 * Initialize bulk URBs and allocate transfer buffers. The packet size is
914 * given by the endpoint.
916 static int uvc_init_video_bulk(struct uvc_streaming
*stream
,
917 struct usb_host_endpoint
*ep
, gfp_t gfp_flags
)
920 unsigned int npackets
, pipe
, i
;
924 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
) & 0x07ff;
925 size
= stream
->ctrl
.dwMaxPayloadTransferSize
;
926 stream
->bulk
.max_payload_size
= size
;
928 npackets
= uvc_alloc_urb_buffers(stream
, size
, psize
, gfp_flags
);
932 size
= npackets
* psize
;
934 if (usb_endpoint_dir_in(&ep
->desc
))
935 pipe
= usb_rcvbulkpipe(stream
->dev
->udev
,
936 ep
->desc
.bEndpointAddress
);
938 pipe
= usb_sndbulkpipe(stream
->dev
->udev
,
939 ep
->desc
.bEndpointAddress
);
941 if (stream
->type
== V4L2_BUF_TYPE_VIDEO_OUTPUT
)
944 for (i
= 0; i
< UVC_URBS
; ++i
) {
945 urb
= usb_alloc_urb(0, gfp_flags
);
947 uvc_uninit_video(stream
, 1);
951 usb_fill_bulk_urb(urb
, stream
->dev
->udev
, pipe
,
952 stream
->urb_buffer
[i
], size
, uvc_video_complete
,
954 urb
->transfer_flags
= URB_NO_TRANSFER_DMA_MAP
;
955 urb
->transfer_dma
= stream
->urb_dma
[i
];
957 stream
->urb
[i
] = urb
;
964 * Initialize isochronous/bulk URBs and allocate transfer buffers.
966 static int uvc_init_video(struct uvc_streaming
*stream
, gfp_t gfp_flags
)
968 struct usb_interface
*intf
= stream
->intf
;
969 struct usb_host_endpoint
*ep
;
973 stream
->last_fid
= -1;
974 stream
->bulk
.header_size
= 0;
975 stream
->bulk
.skip_payload
= 0;
976 stream
->bulk
.payload_size
= 0;
978 if (intf
->num_altsetting
> 1) {
979 struct usb_host_endpoint
*best_ep
= NULL
;
980 unsigned int best_psize
= 3 * 1024;
981 unsigned int bandwidth
;
982 unsigned int uninitialized_var(altsetting
);
983 int intfnum
= stream
->intfnum
;
985 /* Isochronous endpoint, select the alternate setting. */
986 bandwidth
= stream
->ctrl
.dwMaxPayloadTransferSize
;
988 if (bandwidth
== 0) {
989 uvc_trace(UVC_TRACE_VIDEO
, "Device requested null "
990 "bandwidth, defaulting to lowest.\n");
993 uvc_trace(UVC_TRACE_VIDEO
, "Device requested %u "
994 "B/frame bandwidth.\n", bandwidth
);
997 for (i
= 0; i
< intf
->num_altsetting
; ++i
) {
998 struct usb_host_interface
*alts
;
1001 alts
= &intf
->altsetting
[i
];
1002 ep
= uvc_find_endpoint(alts
,
1003 stream
->header
.bEndpointAddress
);
1007 /* Check if the bandwidth is high enough. */
1008 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
);
1009 psize
= (psize
& 0x07ff) * (1 + ((psize
>> 11) & 3));
1010 if (psize
>= bandwidth
&& psize
<= best_psize
) {
1017 if (best_ep
== NULL
) {
1018 uvc_trace(UVC_TRACE_VIDEO
, "No fast enough alt setting "
1019 "for requested bandwidth.\n");
1023 uvc_trace(UVC_TRACE_VIDEO
, "Selecting alternate setting %u "
1024 "(%u B/frame bandwidth).\n", altsetting
, best_psize
);
1026 ret
= usb_set_interface(stream
->dev
->udev
, intfnum
, altsetting
);
1030 ret
= uvc_init_video_isoc(stream
, best_ep
, gfp_flags
);
1032 /* Bulk endpoint, proceed to URB initialization. */
1033 ep
= uvc_find_endpoint(&intf
->altsetting
[0],
1034 stream
->header
.bEndpointAddress
);
1038 ret
= uvc_init_video_bulk(stream
, ep
, gfp_flags
);
1044 /* Submit the URBs. */
1045 for (i
= 0; i
< UVC_URBS
; ++i
) {
1046 ret
= usb_submit_urb(stream
->urb
[i
], gfp_flags
);
1048 uvc_printk(KERN_ERR
, "Failed to submit URB %u "
1050 uvc_uninit_video(stream
, 1);
1058 /* --------------------------------------------------------------------------
1063 * Stop streaming without disabling the video queue.
1065 * To let userspace applications resume without trouble, we must not touch the
1066 * video buffers in any way. We mark the device as frozen to make sure the URB
1067 * completion handler won't try to cancel the queue when we kill the URBs.
1069 int uvc_video_suspend(struct uvc_streaming
*stream
)
1071 if (!uvc_queue_streaming(&stream
->queue
))
1075 uvc_uninit_video(stream
, 0);
1076 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1081 * Reconfigure the video interface and restart streaming if it was enabled
1084 * If an error occurs, disable the video queue. This will wake all pending
1085 * buffers, making sure userspace applications are notified of the problem
1086 * instead of waiting forever.
1088 int uvc_video_resume(struct uvc_streaming
*stream
)
1094 ret
= uvc_commit_video(stream
, &stream
->ctrl
);
1096 uvc_queue_enable(&stream
->queue
, 0);
1100 if (!uvc_queue_streaming(&stream
->queue
))
1103 ret
= uvc_init_video(stream
, GFP_NOIO
);
1105 uvc_queue_enable(&stream
->queue
, 0);
1110 /* ------------------------------------------------------------------------
1115 * Initialize the UVC video device by switching to alternate setting 0 and
1116 * retrieve the default format.
1118 * Some cameras (namely the Fuji Finepix) set the format and frame
1119 * indexes to zero. The UVC standard doesn't clearly make this a spec
1120 * violation, so try to silently fix the values if possible.
1122 * This function is called before registering the device with V4L.
1124 int uvc_video_init(struct uvc_streaming
*stream
)
1126 struct uvc_streaming_control
*probe
= &stream
->ctrl
;
1127 struct uvc_format
*format
= NULL
;
1128 struct uvc_frame
*frame
= NULL
;
1132 if (stream
->nformats
== 0) {
1133 uvc_printk(KERN_INFO
, "No supported video formats found.\n");
1137 atomic_set(&stream
->active
, 0);
1139 /* Initialize the video buffers queue. */
1140 uvc_queue_init(&stream
->queue
, stream
->type
, !uvc_no_drop_param
);
1142 /* Alternate setting 0 should be the default, yet the XBox Live Vision
1143 * Cam (and possibly other devices) crash or otherwise misbehave if
1144 * they don't receive a SET_INTERFACE request before any other video
1147 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1149 /* Set the streaming probe control with default streaming parameters
1150 * retrieved from the device. Webcams that don't suport GET_DEF
1151 * requests on the probe control will just keep their current streaming
1154 if (uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_DEF
) == 0)
1155 uvc_set_video_ctrl(stream
, probe
, 1);
1157 /* Initialize the streaming parameters with the probe control current
1158 * value. This makes sure SET_CUR requests on the streaming commit
1159 * control will always use values retrieved from a successful GET_CUR
1160 * request on the probe control, as required by the UVC specification.
1162 ret
= uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_CUR
);
1166 /* Check if the default format descriptor exists. Use the first
1167 * available format otherwise.
1169 for (i
= stream
->nformats
; i
> 0; --i
) {
1170 format
= &stream
->format
[i
-1];
1171 if (format
->index
== probe
->bFormatIndex
)
1175 if (format
->nframes
== 0) {
1176 uvc_printk(KERN_INFO
, "No frame descriptor found for the "
1177 "default format.\n");
1181 /* Zero bFrameIndex might be correct. Stream-based formats (including
1182 * MPEG-2 TS and DV) do not support frames but have a dummy frame
1183 * descriptor with bFrameIndex set to zero. If the default frame
1184 * descriptor is not found, use the first available frame.
1186 for (i
= format
->nframes
; i
> 0; --i
) {
1187 frame
= &format
->frame
[i
-1];
1188 if (frame
->bFrameIndex
== probe
->bFrameIndex
)
1192 probe
->bFormatIndex
= format
->index
;
1193 probe
->bFrameIndex
= frame
->bFrameIndex
;
1195 stream
->cur_format
= format
;
1196 stream
->cur_frame
= frame
;
1198 /* Select the video decoding function */
1199 if (stream
->type
== V4L2_BUF_TYPE_VIDEO_CAPTURE
) {
1200 if (stream
->dev
->quirks
& UVC_QUIRK_BUILTIN_ISIGHT
)
1201 stream
->decode
= uvc_video_decode_isight
;
1202 else if (stream
->intf
->num_altsetting
> 1)
1203 stream
->decode
= uvc_video_decode_isoc
;
1205 stream
->decode
= uvc_video_decode_bulk
;
1207 if (stream
->intf
->num_altsetting
== 1)
1208 stream
->decode
= uvc_video_encode_bulk
;
1210 uvc_printk(KERN_INFO
, "Isochronous endpoints are not "
1211 "supported for video output devices.\n");
1220 * Enable or disable the video stream.
1222 int uvc_video_enable(struct uvc_streaming
*stream
, int enable
)
1227 uvc_uninit_video(stream
, 1);
1228 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1229 uvc_queue_enable(&stream
->queue
, 0);
1233 ret
= uvc_queue_enable(&stream
->queue
, 1);
1237 /* Commit the streaming parameters. */
1238 ret
= uvc_commit_video(stream
, &stream
->ctrl
);
1242 return uvc_init_video(stream
, GFP_KERNEL
);