diff options
Diffstat (limited to 'drivers/media/video/uvc/uvc_video.c')
| -rw-r--r-- | drivers/media/video/uvc/uvc_video.c | 31 |
1 files changed, 19 insertions, 12 deletions
diff --git a/drivers/media/video/uvc/uvc_video.c b/drivers/media/video/uvc/uvc_video.c index e7c31995527f..9bc4705be78d 100644 --- a/drivers/media/video/uvc/uvc_video.c +++ b/drivers/media/video/uvc/uvc_video.c @@ -1,7 +1,7 @@ /* * uvc_video.c -- USB Video Class driver - Video handling * - * Copyright (C) 2005-2008 + * Copyright (C) 2005-2009 * Laurent Pinchart (laurent.pinchart@skynet.be) * * This program is free software; you can redistribute it and/or modify @@ -12,7 +12,6 @@ */ #include <linux/kernel.h> -#include <linux/version.h> #include <linux/list.h> #include <linux/module.h> #include <linux/usb.h> @@ -115,7 +114,7 @@ static int uvc_get_video_ctrl(struct uvc_video_device *video, ctrl->wCompQuality = le16_to_cpup((__le16 *)data); ret = 0; goto out; - } else if (query == GET_DEF && probe == 1) { + } else if (query == GET_DEF && probe == 1 && ret != size) { /* Many cameras don't support the GET_DEF request on their * video probe control. Warn once and return, the caller will * fall back to GET_CUR. @@ -160,7 +159,7 @@ static int uvc_get_video_ctrl(struct uvc_video_device *video, } /* Some broken devices return a null or wrong dwMaxVideoFrameSize. - * Try to get the value from the format and frame descriptor. + * Try to get the value from the format and frame descriptors. */ uvc_fixup_buffer_size(video, ctrl); ret = 0; @@ -191,9 +190,6 @@ static int uvc_set_video_ctrl(struct uvc_video_device *video, *(__le16 *)&data[12] = cpu_to_le16(ctrl->wCompQuality); *(__le16 *)&data[14] = cpu_to_le16(ctrl->wCompWindowSize); *(__le16 *)&data[16] = cpu_to_le16(ctrl->wDelay); - /* Note: Some of the fields below are not required for IN devices (see - * UVC spec, 4.3.1.1), but we still copy them in case support for OUT - * devices is added in the future. */ put_unaligned_le32(ctrl->dwMaxVideoFrameSize, &data[18]); put_unaligned_le32(ctrl->dwMaxPayloadTransferSize, &data[22]); @@ -400,7 +396,7 @@ static int uvc_video_decode_start(struct uvc_video_device *video, * * Empty buffers (bytesused == 0) don't trigger end of frame detection * as it doesn't make sense to return an empty buffer. This also - * avoids detecting and of frame conditions at FID toggling if the + * avoids detecting end of frame conditions at FID toggling if the * previous payload had the EOF bit set. */ if (fid != video->last_fid && buf->buf.bytesused != 0) { @@ -453,6 +449,17 @@ static void uvc_video_decode_end(struct uvc_video_device *video, } } +/* Video payload encoding is handled by uvc_video_encode_header() and + * uvc_video_encode_data(). Only bulk transfers are currently supported. + * + * uvc_video_encode_header is called at the start of a payload. It adds header + * data to the transfer buffer and returns the header size. As the only known + * UVC output device transfers a whole frame in a single payload, the EOF bit + * is always set in the header. + * + * uvc_video_encode_data is called for every URB and copies the data from the + * video buffer to the transfer buffer. + */ static int uvc_video_encode_header(struct uvc_video_device *video, struct uvc_buffer *buf, __u8 *data, int len) { @@ -953,7 +960,7 @@ int uvc_video_suspend(struct uvc_video_device *video) } /* - * Reconfigure the video interface and restart streaming if it was enable + * Reconfigure the video interface and restart streaming if it was enabled * before suspend. * * If an error occurs, disable the video queue. This will wake all pending @@ -985,8 +992,8 @@ int uvc_video_resume(struct uvc_video_device *video) */ /* - * Initialize the UVC video device by retrieving the default format and - * committing it. + * Initialize the UVC video device by switching to alternate setting 0 and + * retrieve the default format. * * Some cameras (namely the Fuji Finepix) set the format and frame * indexes to zero. The UVC standard doesn't clearly make this a spec @@ -1014,7 +1021,7 @@ int uvc_video_init(struct uvc_video_device *video) */ usb_set_interface(video->dev->udev, video->streaming->intfnum, 0); - /* Some webcams don't suport GET_DEF request on the probe control. We + /* Some webcams don't suport GET_DEF requests on the probe control. We * fall back to GET_CUR if GET_DEF fails. */ if ((ret = uvc_get_video_ctrl(video, probe, 1, GET_DEF)) < 0 && |