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/usb.h>
18 #include <linux/videodev2.h>
19 #include <linux/vmalloc.h>
20 #include <linux/wait.h>
21 #include <asm/atomic.h>
22 #include <asm/unaligned.h>
24 #include <media/v4l2-common.h>
28 /* ------------------------------------------------------------------------
32 static int __uvc_query_ctrl(struct uvc_device
*dev
, __u8 query
, __u8 unit
,
33 __u8 intfnum
, __u8 cs
, void *data
, __u16 size
,
36 __u8 type
= USB_TYPE_CLASS
| USB_RECIP_INTERFACE
;
39 pipe
= (query
& 0x80) ? usb_rcvctrlpipe(dev
->udev
, 0)
40 : usb_sndctrlpipe(dev
->udev
, 0);
41 type
|= (query
& 0x80) ? USB_DIR_IN
: USB_DIR_OUT
;
43 return usb_control_msg(dev
->udev
, pipe
, query
, type
, cs
<< 8,
44 unit
<< 8 | intfnum
, data
, size
, timeout
);
47 int uvc_query_ctrl(struct uvc_device
*dev
, __u8 query
, __u8 unit
,
48 __u8 intfnum
, __u8 cs
, void *data
, __u16 size
)
52 ret
= __uvc_query_ctrl(dev
, query
, unit
, intfnum
, cs
, data
, size
,
53 UVC_CTRL_CONTROL_TIMEOUT
);
55 uvc_printk(KERN_ERR
, "Failed to query (%u) UVC control %u "
56 "(unit %u) : %d (exp. %u).\n", query
, cs
, unit
, ret
,
64 static void uvc_fixup_video_ctrl(struct uvc_streaming
*stream
,
65 struct uvc_streaming_control
*ctrl
)
67 struct uvc_format
*format
= NULL
;
68 struct uvc_frame
*frame
= NULL
;
71 for (i
= 0; i
< stream
->nformats
; ++i
) {
72 if (stream
->format
[i
].index
== ctrl
->bFormatIndex
) {
73 format
= &stream
->format
[i
];
81 for (i
= 0; i
< format
->nframes
; ++i
) {
82 if (format
->frame
[i
].bFrameIndex
== ctrl
->bFrameIndex
) {
83 frame
= &format
->frame
[i
];
91 if (!(format
->flags
& UVC_FMT_FLAG_COMPRESSED
) ||
92 (ctrl
->dwMaxVideoFrameSize
== 0 &&
93 stream
->dev
->uvc_version
< 0x0110))
94 ctrl
->dwMaxVideoFrameSize
=
95 frame
->dwMaxVideoFrameBufferSize
;
97 if (!(format
->flags
& UVC_FMT_FLAG_COMPRESSED
) &&
98 stream
->dev
->quirks
& UVC_QUIRK_FIX_BANDWIDTH
&&
99 stream
->intf
->num_altsetting
> 1) {
103 interval
= (ctrl
->dwFrameInterval
> 100000)
104 ? ctrl
->dwFrameInterval
105 : frame
->dwFrameInterval
[0];
107 /* Compute a bandwidth estimation by multiplying the frame
108 * size by the number of video frames per second, divide the
109 * result by the number of USB frames (or micro-frames for
110 * high-speed devices) per second and add the UVC header size
111 * (assumed to be 12 bytes long).
113 bandwidth
= frame
->wWidth
* frame
->wHeight
/ 8 * format
->bpp
;
114 bandwidth
*= 10000000 / interval
+ 1;
116 if (stream
->dev
->udev
->speed
== USB_SPEED_HIGH
)
120 ctrl
->dwMaxPayloadTransferSize
= bandwidth
;
124 static int uvc_get_video_ctrl(struct uvc_streaming
*stream
,
125 struct uvc_streaming_control
*ctrl
, int probe
, __u8 query
)
131 size
= stream
->dev
->uvc_version
>= 0x0110 ? 34 : 26;
132 if ((stream
->dev
->quirks
& UVC_QUIRK_PROBE_DEF
) &&
133 query
== UVC_GET_DEF
)
136 data
= kmalloc(size
, GFP_KERNEL
);
140 ret
= __uvc_query_ctrl(stream
->dev
, query
, 0, stream
->intfnum
,
141 probe
? UVC_VS_PROBE_CONTROL
: UVC_VS_COMMIT_CONTROL
, data
,
142 size
, UVC_CTRL_STREAMING_TIMEOUT
);
144 if ((query
== UVC_GET_MIN
|| query
== UVC_GET_MAX
) && ret
== 2) {
145 /* Some cameras, mostly based on Bison Electronics chipsets,
146 * answer a GET_MIN or GET_MAX request with the wCompQuality
149 uvc_warn_once(stream
->dev
, UVC_WARN_MINMAX
, "UVC non "
150 "compliance - GET_MIN/MAX(PROBE) incorrectly "
151 "supported. Enabling workaround.\n");
152 memset(ctrl
, 0, sizeof ctrl
);
153 ctrl
->wCompQuality
= le16_to_cpup((__le16
*)data
);
156 } else if (query
== UVC_GET_DEF
&& probe
== 1 && ret
!= size
) {
157 /* Many cameras don't support the GET_DEF request on their
158 * video probe control. Warn once and return, the caller will
159 * fall back to GET_CUR.
161 uvc_warn_once(stream
->dev
, UVC_WARN_PROBE_DEF
, "UVC non "
162 "compliance - GET_DEF(PROBE) not supported. "
163 "Enabling workaround.\n");
166 } else if (ret
!= size
) {
167 uvc_printk(KERN_ERR
, "Failed to query (%u) UVC %s control : "
168 "%d (exp. %u).\n", query
, probe
? "probe" : "commit",
174 ctrl
->bmHint
= le16_to_cpup((__le16
*)&data
[0]);
175 ctrl
->bFormatIndex
= data
[2];
176 ctrl
->bFrameIndex
= data
[3];
177 ctrl
->dwFrameInterval
= le32_to_cpup((__le32
*)&data
[4]);
178 ctrl
->wKeyFrameRate
= le16_to_cpup((__le16
*)&data
[8]);
179 ctrl
->wPFrameRate
= le16_to_cpup((__le16
*)&data
[10]);
180 ctrl
->wCompQuality
= le16_to_cpup((__le16
*)&data
[12]);
181 ctrl
->wCompWindowSize
= le16_to_cpup((__le16
*)&data
[14]);
182 ctrl
->wDelay
= le16_to_cpup((__le16
*)&data
[16]);
183 ctrl
->dwMaxVideoFrameSize
= get_unaligned_le32(&data
[18]);
184 ctrl
->dwMaxPayloadTransferSize
= get_unaligned_le32(&data
[22]);
187 ctrl
->dwClockFrequency
= get_unaligned_le32(&data
[26]);
188 ctrl
->bmFramingInfo
= data
[30];
189 ctrl
->bPreferedVersion
= data
[31];
190 ctrl
->bMinVersion
= data
[32];
191 ctrl
->bMaxVersion
= data
[33];
193 ctrl
->dwClockFrequency
= stream
->dev
->clock_frequency
;
194 ctrl
->bmFramingInfo
= 0;
195 ctrl
->bPreferedVersion
= 0;
196 ctrl
->bMinVersion
= 0;
197 ctrl
->bMaxVersion
= 0;
200 /* Some broken devices return null or wrong dwMaxVideoFrameSize and
201 * dwMaxPayloadTransferSize fields. Try to get the value from the
202 * format and frame descriptors.
204 uvc_fixup_video_ctrl(stream
, ctrl
);
212 static int uvc_set_video_ctrl(struct uvc_streaming
*stream
,
213 struct uvc_streaming_control
*ctrl
, int probe
)
219 size
= stream
->dev
->uvc_version
>= 0x0110 ? 34 : 26;
220 data
= kzalloc(size
, GFP_KERNEL
);
224 *(__le16
*)&data
[0] = cpu_to_le16(ctrl
->bmHint
);
225 data
[2] = ctrl
->bFormatIndex
;
226 data
[3] = ctrl
->bFrameIndex
;
227 *(__le32
*)&data
[4] = cpu_to_le32(ctrl
->dwFrameInterval
);
228 *(__le16
*)&data
[8] = cpu_to_le16(ctrl
->wKeyFrameRate
);
229 *(__le16
*)&data
[10] = cpu_to_le16(ctrl
->wPFrameRate
);
230 *(__le16
*)&data
[12] = cpu_to_le16(ctrl
->wCompQuality
);
231 *(__le16
*)&data
[14] = cpu_to_le16(ctrl
->wCompWindowSize
);
232 *(__le16
*)&data
[16] = cpu_to_le16(ctrl
->wDelay
);
233 put_unaligned_le32(ctrl
->dwMaxVideoFrameSize
, &data
[18]);
234 put_unaligned_le32(ctrl
->dwMaxPayloadTransferSize
, &data
[22]);
237 put_unaligned_le32(ctrl
->dwClockFrequency
, &data
[26]);
238 data
[30] = ctrl
->bmFramingInfo
;
239 data
[31] = ctrl
->bPreferedVersion
;
240 data
[32] = ctrl
->bMinVersion
;
241 data
[33] = ctrl
->bMaxVersion
;
244 ret
= __uvc_query_ctrl(stream
->dev
, UVC_SET_CUR
, 0, stream
->intfnum
,
245 probe
? UVC_VS_PROBE_CONTROL
: UVC_VS_COMMIT_CONTROL
, data
,
246 size
, UVC_CTRL_STREAMING_TIMEOUT
);
248 uvc_printk(KERN_ERR
, "Failed to set UVC %s control : "
249 "%d (exp. %u).\n", probe
? "probe" : "commit",
258 int uvc_probe_video(struct uvc_streaming
*stream
,
259 struct uvc_streaming_control
*probe
)
261 struct uvc_streaming_control probe_min
, probe_max
;
266 mutex_lock(&stream
->mutex
);
268 /* Perform probing. The device should adjust the requested values
269 * according to its capabilities. However, some devices, namely the
270 * first generation UVC Logitech webcams, don't implement the Video
271 * Probe control properly, and just return the needed bandwidth. For
272 * that reason, if the needed bandwidth exceeds the maximum available
273 * bandwidth, try to lower the quality.
275 ret
= uvc_set_video_ctrl(stream
, probe
, 1);
279 /* Get the minimum and maximum values for compression settings. */
280 if (!(stream
->dev
->quirks
& UVC_QUIRK_PROBE_MINMAX
)) {
281 ret
= uvc_get_video_ctrl(stream
, &probe_min
, 1, UVC_GET_MIN
);
284 ret
= uvc_get_video_ctrl(stream
, &probe_max
, 1, UVC_GET_MAX
);
288 probe
->wCompQuality
= probe_max
.wCompQuality
;
291 for (i
= 0; i
< 2; ++i
) {
292 ret
= uvc_set_video_ctrl(stream
, probe
, 1);
295 ret
= uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_CUR
);
299 if (stream
->intf
->num_altsetting
== 1)
302 bandwidth
= probe
->dwMaxPayloadTransferSize
;
303 if (bandwidth
<= stream
->maxpsize
)
306 if (stream
->dev
->quirks
& UVC_QUIRK_PROBE_MINMAX
) {
311 /* TODO: negotiate compression parameters */
312 probe
->wKeyFrameRate
= probe_min
.wKeyFrameRate
;
313 probe
->wPFrameRate
= probe_min
.wPFrameRate
;
314 probe
->wCompQuality
= probe_max
.wCompQuality
;
315 probe
->wCompWindowSize
= probe_min
.wCompWindowSize
;
319 mutex_unlock(&stream
->mutex
);
323 int uvc_commit_video(struct uvc_streaming
*stream
,
324 struct uvc_streaming_control
*probe
)
326 return uvc_set_video_ctrl(stream
, probe
, 0);
329 /* ------------------------------------------------------------------------
333 /* Values for bmHeaderInfo (Video and Still Image Payload Headers, 2.4.3.3) */
334 #define UVC_STREAM_EOH (1 << 7)
335 #define UVC_STREAM_ERR (1 << 6)
336 #define UVC_STREAM_STI (1 << 5)
337 #define UVC_STREAM_RES (1 << 4)
338 #define UVC_STREAM_SCR (1 << 3)
339 #define UVC_STREAM_PTS (1 << 2)
340 #define UVC_STREAM_EOF (1 << 1)
341 #define UVC_STREAM_FID (1 << 0)
343 /* Video payload decoding is handled by uvc_video_decode_start(),
344 * uvc_video_decode_data() and uvc_video_decode_end().
346 * uvc_video_decode_start is called with URB data at the start of a bulk or
347 * isochronous payload. It processes header data and returns the header size
348 * in bytes if successful. If an error occurs, it returns a negative error
349 * code. The following error codes have special meanings.
351 * - EAGAIN informs the caller that the current video buffer should be marked
352 * as done, and that the function should be called again with the same data
353 * and a new video buffer. This is used when end of frame conditions can be
354 * reliably detected at the beginning of the next frame only.
356 * If an error other than -EAGAIN is returned, the caller will drop the current
357 * payload. No call to uvc_video_decode_data and uvc_video_decode_end will be
358 * made until the next payload. -ENODATA can be used to drop the current
359 * payload if no other error code is appropriate.
361 * uvc_video_decode_data is called for every URB with URB data. It copies the
362 * data to the video buffer.
364 * uvc_video_decode_end is called with header data at the end of a bulk or
365 * isochronous payload. It performs any additional header data processing and
366 * returns 0 or a negative error code if an error occured. As header data have
367 * already been processed by uvc_video_decode_start, this functions isn't
368 * required to perform sanity checks a second time.
370 * For isochronous transfers where a payload is always transfered in a single
371 * URB, the three functions will be called in a row.
373 * To let the decoder process header data and update its internal state even
374 * when no video buffer is available, uvc_video_decode_start must be prepared
375 * to be called with a NULL buf parameter. uvc_video_decode_data and
376 * uvc_video_decode_end will never be called with a NULL buffer.
378 static int uvc_video_decode_start(struct uvc_streaming
*stream
,
379 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
384 * - packet must be at least 2 bytes long
385 * - bHeaderLength value must be at least 2 bytes (see above)
386 * - bHeaderLength value can't be larger than the packet size.
388 if (len
< 2 || data
[0] < 2 || data
[0] > len
)
391 /* Skip payloads marked with the error bit ("error frames"). */
392 if (data
[1] & UVC_STREAM_ERR
) {
393 uvc_trace(UVC_TRACE_FRAME
, "Dropping payload (error bit "
398 fid
= data
[1] & UVC_STREAM_FID
;
400 /* Store the payload FID bit and return immediately when the buffer is
404 stream
->last_fid
= fid
;
408 /* Synchronize to the input stream by waiting for the FID bit to be
409 * toggled when the the buffer state is not UVC_BUF_STATE_ACTIVE.
410 * stream->last_fid is initialized to -1, so the first isochronous
411 * frame will always be in sync.
413 * If the device doesn't toggle the FID bit, invert stream->last_fid
414 * when the EOF bit is set to force synchronisation on the next packet.
416 if (buf
->state
!= UVC_BUF_STATE_ACTIVE
) {
417 if (fid
== stream
->last_fid
) {
418 uvc_trace(UVC_TRACE_FRAME
, "Dropping payload (out of "
420 if ((stream
->dev
->quirks
& UVC_QUIRK_STREAM_NO_FID
) &&
421 (data
[1] & UVC_STREAM_EOF
))
422 stream
->last_fid
^= UVC_STREAM_FID
;
426 /* TODO: Handle PTS and SCR. */
427 buf
->state
= UVC_BUF_STATE_ACTIVE
;
430 /* Mark the buffer as done if we're at the beginning of a new frame.
431 * End of frame detection is better implemented by checking the EOF
432 * bit (FID bit toggling is delayed by one frame compared to the EOF
433 * bit), but some devices don't set the bit at end of frame (and the
434 * last payload can be lost anyway). We thus must check if the FID has
437 * stream->last_fid is initialized to -1, so the first isochronous
438 * frame will never trigger an end of frame detection.
440 * Empty buffers (bytesused == 0) don't trigger end of frame detection
441 * as it doesn't make sense to return an empty buffer. This also
442 * avoids detecting end of frame conditions at FID toggling if the
443 * previous payload had the EOF bit set.
445 if (fid
!= stream
->last_fid
&& buf
->buf
.bytesused
!= 0) {
446 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (FID bit "
448 buf
->state
= UVC_BUF_STATE_DONE
;
452 stream
->last_fid
= fid
;
457 static void uvc_video_decode_data(struct uvc_streaming
*stream
,
458 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
460 struct uvc_video_queue
*queue
= &stream
->queue
;
461 unsigned int maxlen
, nbytes
;
467 /* Copy the video data to the buffer. */
468 maxlen
= buf
->buf
.length
- buf
->buf
.bytesused
;
469 mem
= queue
->mem
+ buf
->buf
.m
.offset
+ buf
->buf
.bytesused
;
470 nbytes
= min((unsigned int)len
, maxlen
);
471 memcpy(mem
, data
, nbytes
);
472 buf
->buf
.bytesused
+= nbytes
;
474 /* Complete the current frame if the buffer size was exceeded. */
476 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (overflow).\n");
477 buf
->state
= UVC_BUF_STATE_DONE
;
481 static void uvc_video_decode_end(struct uvc_streaming
*stream
,
482 struct uvc_buffer
*buf
, const __u8
*data
, int len
)
484 /* Mark the buffer as done if the EOF marker is set. */
485 if (data
[1] & UVC_STREAM_EOF
&& buf
->buf
.bytesused
!= 0) {
486 uvc_trace(UVC_TRACE_FRAME
, "Frame complete (EOF found).\n");
488 uvc_trace(UVC_TRACE_FRAME
, "EOF in empty payload.\n");
489 buf
->state
= UVC_BUF_STATE_DONE
;
490 if (stream
->dev
->quirks
& UVC_QUIRK_STREAM_NO_FID
)
491 stream
->last_fid
^= UVC_STREAM_FID
;
495 /* Video payload encoding is handled by uvc_video_encode_header() and
496 * uvc_video_encode_data(). Only bulk transfers are currently supported.
498 * uvc_video_encode_header is called at the start of a payload. It adds header
499 * data to the transfer buffer and returns the header size. As the only known
500 * UVC output device transfers a whole frame in a single payload, the EOF bit
501 * is always set in the header.
503 * uvc_video_encode_data is called for every URB and copies the data from the
504 * video buffer to the transfer buffer.
506 static int uvc_video_encode_header(struct uvc_streaming
*stream
,
507 struct uvc_buffer
*buf
, __u8
*data
, int len
)
509 data
[0] = 2; /* Header length */
510 data
[1] = UVC_STREAM_EOH
| UVC_STREAM_EOF
511 | (stream
->last_fid
& UVC_STREAM_FID
);
515 static int uvc_video_encode_data(struct uvc_streaming
*stream
,
516 struct uvc_buffer
*buf
, __u8
*data
, int len
)
518 struct uvc_video_queue
*queue
= &stream
->queue
;
522 /* Copy video data to the URB buffer. */
523 mem
= queue
->mem
+ buf
->buf
.m
.offset
+ queue
->buf_used
;
524 nbytes
= min((unsigned int)len
, buf
->buf
.bytesused
- queue
->buf_used
);
525 nbytes
= min(stream
->bulk
.max_payload_size
- stream
->bulk
.payload_size
,
527 memcpy(data
, mem
, nbytes
);
529 queue
->buf_used
+= nbytes
;
534 /* ------------------------------------------------------------------------
539 * Completion handler for video URBs.
541 static void uvc_video_decode_isoc(struct urb
*urb
, struct uvc_streaming
*stream
,
542 struct uvc_buffer
*buf
)
547 for (i
= 0; i
< urb
->number_of_packets
; ++i
) {
548 if (urb
->iso_frame_desc
[i
].status
< 0) {
549 uvc_trace(UVC_TRACE_FRAME
, "USB isochronous frame "
550 "lost (%d).\n", urb
->iso_frame_desc
[i
].status
);
554 /* Decode the payload header. */
555 mem
= urb
->transfer_buffer
+ urb
->iso_frame_desc
[i
].offset
;
557 ret
= uvc_video_decode_start(stream
, buf
, mem
,
558 urb
->iso_frame_desc
[i
].actual_length
);
560 buf
= uvc_queue_next_buffer(&stream
->queue
,
562 } while (ret
== -EAGAIN
);
567 /* Decode the payload data. */
568 uvc_video_decode_data(stream
, buf
, mem
+ ret
,
569 urb
->iso_frame_desc
[i
].actual_length
- ret
);
571 /* Process the header again. */
572 uvc_video_decode_end(stream
, buf
, mem
,
573 urb
->iso_frame_desc
[i
].actual_length
);
575 if (buf
->state
== UVC_BUF_STATE_DONE
||
576 buf
->state
== UVC_BUF_STATE_ERROR
)
577 buf
= uvc_queue_next_buffer(&stream
->queue
, buf
);
581 static void uvc_video_decode_bulk(struct urb
*urb
, struct uvc_streaming
*stream
,
582 struct uvc_buffer
*buf
)
587 if (urb
->actual_length
== 0)
590 mem
= urb
->transfer_buffer
;
591 len
= urb
->actual_length
;
592 stream
->bulk
.payload_size
+= len
;
594 /* If the URB is the first of its payload, decode and save the
597 if (stream
->bulk
.header_size
== 0 && !stream
->bulk
.skip_payload
) {
599 ret
= uvc_video_decode_start(stream
, buf
, mem
, len
);
601 buf
= uvc_queue_next_buffer(&stream
->queue
,
603 } while (ret
== -EAGAIN
);
605 /* If an error occured skip the rest of the payload. */
606 if (ret
< 0 || buf
== NULL
) {
607 stream
->bulk
.skip_payload
= 1;
609 memcpy(stream
->bulk
.header
, mem
, ret
);
610 stream
->bulk
.header_size
= ret
;
617 /* The buffer queue might have been cancelled while a bulk transfer
618 * was in progress, so we can reach here with buf equal to NULL. Make
619 * sure buf is never dereferenced if NULL.
622 /* Process video data. */
623 if (!stream
->bulk
.skip_payload
&& buf
!= NULL
)
624 uvc_video_decode_data(stream
, buf
, mem
, len
);
626 /* Detect the payload end by a URB smaller than the maximum size (or
627 * a payload size equal to the maximum) and process the header again.
629 if (urb
->actual_length
< urb
->transfer_buffer_length
||
630 stream
->bulk
.payload_size
>= stream
->bulk
.max_payload_size
) {
631 if (!stream
->bulk
.skip_payload
&& buf
!= NULL
) {
632 uvc_video_decode_end(stream
, buf
, stream
->bulk
.header
,
633 stream
->bulk
.payload_size
);
634 if (buf
->state
== UVC_BUF_STATE_DONE
||
635 buf
->state
== UVC_BUF_STATE_ERROR
)
636 buf
= uvc_queue_next_buffer(&stream
->queue
,
640 stream
->bulk
.header_size
= 0;
641 stream
->bulk
.skip_payload
= 0;
642 stream
->bulk
.payload_size
= 0;
646 static void uvc_video_encode_bulk(struct urb
*urb
, struct uvc_streaming
*stream
,
647 struct uvc_buffer
*buf
)
649 u8
*mem
= urb
->transfer_buffer
;
650 int len
= stream
->urb_size
, ret
;
653 urb
->transfer_buffer_length
= 0;
657 /* If the URB is the first of its payload, add the header. */
658 if (stream
->bulk
.header_size
== 0) {
659 ret
= uvc_video_encode_header(stream
, buf
, mem
, len
);
660 stream
->bulk
.header_size
= ret
;
661 stream
->bulk
.payload_size
+= ret
;
666 /* Process video data. */
667 ret
= uvc_video_encode_data(stream
, buf
, mem
, len
);
669 stream
->bulk
.payload_size
+= ret
;
672 if (buf
->buf
.bytesused
== stream
->queue
.buf_used
||
673 stream
->bulk
.payload_size
== stream
->bulk
.max_payload_size
) {
674 if (buf
->buf
.bytesused
== stream
->queue
.buf_used
) {
675 stream
->queue
.buf_used
= 0;
676 buf
->state
= UVC_BUF_STATE_DONE
;
677 uvc_queue_next_buffer(&stream
->queue
, buf
);
678 stream
->last_fid
^= UVC_STREAM_FID
;
681 stream
->bulk
.header_size
= 0;
682 stream
->bulk
.payload_size
= 0;
685 urb
->transfer_buffer_length
= stream
->urb_size
- len
;
688 static void uvc_video_complete(struct urb
*urb
)
690 struct uvc_streaming
*stream
= urb
->context
;
691 struct uvc_video_queue
*queue
= &stream
->queue
;
692 struct uvc_buffer
*buf
= NULL
;
696 switch (urb
->status
) {
701 uvc_printk(KERN_WARNING
, "Non-zero status (%d) in video "
702 "completion handler.\n", urb
->status
);
704 case -ENOENT
: /* usb_kill_urb() called. */
708 case -ECONNRESET
: /* usb_unlink_urb() called. */
709 case -ESHUTDOWN
: /* The endpoint is being disabled. */
710 uvc_queue_cancel(queue
, urb
->status
== -ESHUTDOWN
);
714 spin_lock_irqsave(&queue
->irqlock
, flags
);
715 if (!list_empty(&queue
->irqqueue
))
716 buf
= list_first_entry(&queue
->irqqueue
, struct uvc_buffer
,
718 spin_unlock_irqrestore(&queue
->irqlock
, flags
);
720 stream
->decode(urb
, stream
, buf
);
722 if ((ret
= usb_submit_urb(urb
, GFP_ATOMIC
)) < 0) {
723 uvc_printk(KERN_ERR
, "Failed to resubmit video URB (%d).\n",
729 * Free transfer buffers.
731 static void uvc_free_urb_buffers(struct uvc_streaming
*stream
)
735 for (i
= 0; i
< UVC_URBS
; ++i
) {
736 if (stream
->urb_buffer
[i
]) {
737 usb_buffer_free(stream
->dev
->udev
, stream
->urb_size
,
738 stream
->urb_buffer
[i
], stream
->urb_dma
[i
]);
739 stream
->urb_buffer
[i
] = NULL
;
743 stream
->urb_size
= 0;
747 * Allocate transfer buffers. This function can be called with buffers
748 * already allocated when resuming from suspend, in which case it will
749 * return without touching the buffers.
751 * Limit the buffer size to UVC_MAX_PACKETS bulk/isochronous packets. If the
752 * system is too low on memory try successively smaller numbers of packets
753 * until allocation succeeds.
755 * Return the number of allocated packets on success or 0 when out of memory.
757 static int uvc_alloc_urb_buffers(struct uvc_streaming
*stream
,
758 unsigned int size
, unsigned int psize
, gfp_t gfp_flags
)
760 unsigned int npackets
;
763 /* Buffers are already allocated, bail out. */
764 if (stream
->urb_size
)
765 return stream
->urb_size
/ psize
;
767 /* Compute the number of packets. Bulk endpoints might transfer UVC
768 * payloads accross multiple URBs.
770 npackets
= DIV_ROUND_UP(size
, psize
);
771 if (npackets
> UVC_MAX_PACKETS
)
772 npackets
= UVC_MAX_PACKETS
;
774 /* Retry allocations until one succeed. */
775 for (; npackets
> 1; npackets
/= 2) {
776 for (i
= 0; i
< UVC_URBS
; ++i
) {
777 stream
->urb_buffer
[i
] = usb_buffer_alloc(
778 stream
->dev
->udev
, psize
* npackets
,
779 gfp_flags
| __GFP_NOWARN
, &stream
->urb_dma
[i
]);
780 if (!stream
->urb_buffer
[i
]) {
781 uvc_free_urb_buffers(stream
);
787 stream
->urb_size
= psize
* npackets
;
796 * Uninitialize isochronous/bulk URBs and free transfer buffers.
798 static void uvc_uninit_video(struct uvc_streaming
*stream
, int free_buffers
)
803 for (i
= 0; i
< UVC_URBS
; ++i
) {
804 urb
= stream
->urb
[i
];
810 stream
->urb
[i
] = NULL
;
814 uvc_free_urb_buffers(stream
);
818 * Initialize isochronous URBs and allocate transfer buffers. The packet size
819 * is given by the endpoint.
821 static int uvc_init_video_isoc(struct uvc_streaming
*stream
,
822 struct usb_host_endpoint
*ep
, gfp_t gfp_flags
)
825 unsigned int npackets
, i
, j
;
829 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
);
830 psize
= (psize
& 0x07ff) * (1 + ((psize
>> 11) & 3));
831 size
= stream
->ctrl
.dwMaxVideoFrameSize
;
833 npackets
= uvc_alloc_urb_buffers(stream
, size
, psize
, gfp_flags
);
837 size
= npackets
* psize
;
839 for (i
= 0; i
< UVC_URBS
; ++i
) {
840 urb
= usb_alloc_urb(npackets
, gfp_flags
);
842 uvc_uninit_video(stream
, 1);
846 urb
->dev
= stream
->dev
->udev
;
847 urb
->context
= stream
;
848 urb
->pipe
= usb_rcvisocpipe(stream
->dev
->udev
,
849 ep
->desc
.bEndpointAddress
);
850 urb
->transfer_flags
= URB_ISO_ASAP
| URB_NO_TRANSFER_DMA_MAP
;
851 urb
->interval
= ep
->desc
.bInterval
;
852 urb
->transfer_buffer
= stream
->urb_buffer
[i
];
853 urb
->transfer_dma
= stream
->urb_dma
[i
];
854 urb
->complete
= uvc_video_complete
;
855 urb
->number_of_packets
= npackets
;
856 urb
->transfer_buffer_length
= size
;
858 for (j
= 0; j
< npackets
; ++j
) {
859 urb
->iso_frame_desc
[j
].offset
= j
* psize
;
860 urb
->iso_frame_desc
[j
].length
= psize
;
863 stream
->urb
[i
] = urb
;
870 * Initialize bulk URBs and allocate transfer buffers. The packet size is
871 * given by the endpoint.
873 static int uvc_init_video_bulk(struct uvc_streaming
*stream
,
874 struct usb_host_endpoint
*ep
, gfp_t gfp_flags
)
877 unsigned int npackets
, pipe
, i
;
881 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
) & 0x07ff;
882 size
= stream
->ctrl
.dwMaxPayloadTransferSize
;
883 stream
->bulk
.max_payload_size
= size
;
885 npackets
= uvc_alloc_urb_buffers(stream
, size
, psize
, gfp_flags
);
889 size
= npackets
* psize
;
891 if (usb_endpoint_dir_in(&ep
->desc
))
892 pipe
= usb_rcvbulkpipe(stream
->dev
->udev
,
893 ep
->desc
.bEndpointAddress
);
895 pipe
= usb_sndbulkpipe(stream
->dev
->udev
,
896 ep
->desc
.bEndpointAddress
);
898 if (stream
->type
== V4L2_BUF_TYPE_VIDEO_OUTPUT
)
901 for (i
= 0; i
< UVC_URBS
; ++i
) {
902 urb
= usb_alloc_urb(0, gfp_flags
);
904 uvc_uninit_video(stream
, 1);
908 usb_fill_bulk_urb(urb
, stream
->dev
->udev
, pipe
,
909 stream
->urb_buffer
[i
], size
, uvc_video_complete
,
911 urb
->transfer_flags
= URB_NO_TRANSFER_DMA_MAP
;
912 urb
->transfer_dma
= stream
->urb_dma
[i
];
914 stream
->urb
[i
] = urb
;
921 * Initialize isochronous/bulk URBs and allocate transfer buffers.
923 static int uvc_init_video(struct uvc_streaming
*stream
, gfp_t gfp_flags
)
925 struct usb_interface
*intf
= stream
->intf
;
926 struct usb_host_interface
*alts
;
927 struct usb_host_endpoint
*ep
= NULL
;
928 int intfnum
= stream
->intfnum
;
929 unsigned int bandwidth
, psize
, i
;
932 stream
->last_fid
= -1;
933 stream
->bulk
.header_size
= 0;
934 stream
->bulk
.skip_payload
= 0;
935 stream
->bulk
.payload_size
= 0;
937 if (intf
->num_altsetting
> 1) {
938 /* Isochronous endpoint, select the alternate setting. */
939 bandwidth
= stream
->ctrl
.dwMaxPayloadTransferSize
;
941 if (bandwidth
== 0) {
942 uvc_printk(KERN_WARNING
, "device %s requested null "
943 "bandwidth, defaulting to lowest.\n",
948 for (i
= 0; i
< intf
->num_altsetting
; ++i
) {
949 alts
= &intf
->altsetting
[i
];
950 ep
= uvc_find_endpoint(alts
,
951 stream
->header
.bEndpointAddress
);
955 /* Check if the bandwidth is high enough. */
956 psize
= le16_to_cpu(ep
->desc
.wMaxPacketSize
);
957 psize
= (psize
& 0x07ff) * (1 + ((psize
>> 11) & 3));
958 if (psize
>= bandwidth
)
962 if (i
>= intf
->num_altsetting
)
965 ret
= usb_set_interface(stream
->dev
->udev
, intfnum
, i
);
969 ret
= uvc_init_video_isoc(stream
, ep
, gfp_flags
);
971 /* Bulk endpoint, proceed to URB initialization. */
972 ep
= uvc_find_endpoint(&intf
->altsetting
[0],
973 stream
->header
.bEndpointAddress
);
977 ret
= uvc_init_video_bulk(stream
, ep
, gfp_flags
);
983 /* Submit the URBs. */
984 for (i
= 0; i
< UVC_URBS
; ++i
) {
985 ret
= usb_submit_urb(stream
->urb
[i
], gfp_flags
);
987 uvc_printk(KERN_ERR
, "Failed to submit URB %u "
989 uvc_uninit_video(stream
, 1);
997 /* --------------------------------------------------------------------------
1002 * Stop streaming without disabling the video queue.
1004 * To let userspace applications resume without trouble, we must not touch the
1005 * video buffers in any way. We mark the device as frozen to make sure the URB
1006 * completion handler won't try to cancel the queue when we kill the URBs.
1008 int uvc_video_suspend(struct uvc_streaming
*stream
)
1010 if (!uvc_queue_streaming(&stream
->queue
))
1014 uvc_uninit_video(stream
, 0);
1015 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1020 * Reconfigure the video interface and restart streaming if it was enabled
1023 * If an error occurs, disable the video queue. This will wake all pending
1024 * buffers, making sure userspace applications are notified of the problem
1025 * instead of waiting forever.
1027 int uvc_video_resume(struct uvc_streaming
*stream
, int reset
)
1031 /* If the bus has been reset on resume, set the alternate setting to 0.
1032 * This should be the default value, but some devices crash or otherwise
1033 * misbehave if they don't receive a SET_INTERFACE request before any
1034 * other video control request.
1037 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1041 ret
= uvc_commit_video(stream
, &stream
->ctrl
);
1043 uvc_queue_enable(&stream
->queue
, 0);
1047 if (!uvc_queue_streaming(&stream
->queue
))
1050 ret
= uvc_init_video(stream
, GFP_NOIO
);
1052 uvc_queue_enable(&stream
->queue
, 0);
1057 /* ------------------------------------------------------------------------
1062 * Initialize the UVC video device by switching to alternate setting 0 and
1063 * retrieve the default format.
1065 * Some cameras (namely the Fuji Finepix) set the format and frame
1066 * indexes to zero. The UVC standard doesn't clearly make this a spec
1067 * violation, so try to silently fix the values if possible.
1069 * This function is called before registering the device with V4L.
1071 int uvc_video_init(struct uvc_streaming
*stream
)
1073 struct uvc_streaming_control
*probe
= &stream
->ctrl
;
1074 struct uvc_format
*format
= NULL
;
1075 struct uvc_frame
*frame
= NULL
;
1079 if (stream
->nformats
== 0) {
1080 uvc_printk(KERN_INFO
, "No supported video formats found.\n");
1084 atomic_set(&stream
->active
, 0);
1086 /* Initialize the video buffers queue. */
1087 uvc_queue_init(&stream
->queue
, stream
->type
);
1089 /* Alternate setting 0 should be the default, yet the XBox Live Vision
1090 * Cam (and possibly other devices) crash or otherwise misbehave if
1091 * they don't receive a SET_INTERFACE request before any other video
1094 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1096 /* Set the streaming probe control with default streaming parameters
1097 * retrieved from the device. Webcams that don't suport GET_DEF
1098 * requests on the probe control will just keep their current streaming
1101 if (uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_DEF
) == 0)
1102 uvc_set_video_ctrl(stream
, probe
, 1);
1104 /* Initialize the streaming parameters with the probe control current
1105 * value. This makes sure SET_CUR requests on the streaming commit
1106 * control will always use values retrieved from a successful GET_CUR
1107 * request on the probe control, as required by the UVC specification.
1109 ret
= uvc_get_video_ctrl(stream
, probe
, 1, UVC_GET_CUR
);
1113 /* Check if the default format descriptor exists. Use the first
1114 * available format otherwise.
1116 for (i
= stream
->nformats
; i
> 0; --i
) {
1117 format
= &stream
->format
[i
-1];
1118 if (format
->index
== probe
->bFormatIndex
)
1122 if (format
->nframes
== 0) {
1123 uvc_printk(KERN_INFO
, "No frame descriptor found for the "
1124 "default format.\n");
1128 /* Zero bFrameIndex might be correct. Stream-based formats (including
1129 * MPEG-2 TS and DV) do not support frames but have a dummy frame
1130 * descriptor with bFrameIndex set to zero. If the default frame
1131 * descriptor is not found, use the first available frame.
1133 for (i
= format
->nframes
; i
> 0; --i
) {
1134 frame
= &format
->frame
[i
-1];
1135 if (frame
->bFrameIndex
== probe
->bFrameIndex
)
1139 probe
->bFormatIndex
= format
->index
;
1140 probe
->bFrameIndex
= frame
->bFrameIndex
;
1142 stream
->cur_format
= format
;
1143 stream
->cur_frame
= frame
;
1145 /* Select the video decoding function */
1146 if (stream
->type
== V4L2_BUF_TYPE_VIDEO_CAPTURE
) {
1147 if (stream
->dev
->quirks
& UVC_QUIRK_BUILTIN_ISIGHT
)
1148 stream
->decode
= uvc_video_decode_isight
;
1149 else if (stream
->intf
->num_altsetting
> 1)
1150 stream
->decode
= uvc_video_decode_isoc
;
1152 stream
->decode
= uvc_video_decode_bulk
;
1154 if (stream
->intf
->num_altsetting
== 1)
1155 stream
->decode
= uvc_video_encode_bulk
;
1157 uvc_printk(KERN_INFO
, "Isochronous endpoints are not "
1158 "supported for video output devices.\n");
1167 * Enable or disable the video stream.
1169 int uvc_video_enable(struct uvc_streaming
*stream
, int enable
)
1174 uvc_uninit_video(stream
, 1);
1175 usb_set_interface(stream
->dev
->udev
, stream
->intfnum
, 0);
1176 uvc_queue_enable(&stream
->queue
, 0);
1180 if ((stream
->cur_format
->flags
& UVC_FMT_FLAG_COMPRESSED
) ||
1182 stream
->queue
.flags
&= ~UVC_QUEUE_DROP_INCOMPLETE
;
1184 stream
->queue
.flags
|= UVC_QUEUE_DROP_INCOMPLETE
;
1186 ret
= uvc_queue_enable(&stream
->queue
, 1);
1190 /* Commit the streaming parameters. */
1191 ret
= uvc_commit_video(stream
, &stream
->ctrl
);
1195 return uvc_init_video(stream
, GFP_KERNEL
);