diff options
Diffstat (limited to 'drivers/media/video/uvc/uvc_video.c')
| -rw-r--r-- | drivers/media/video/uvc/uvc_video.c | 934 |
1 files changed, 934 insertions, 0 deletions
diff --git a/drivers/media/video/uvc/uvc_video.c b/drivers/media/video/uvc/uvc_video.c new file mode 100644 index 0000000..6faf1fb --- /dev/null +++ b/drivers/media/video/uvc/uvc_video.c @@ -0,0 +1,934 @@ +/* + * uvc_video.c -- USB Video Class driver - Video handling + * + * Copyright (C) 2005-2008 + * Laurent Pinchart (laurent.pinchart@skynet.be) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + */ + +#include <linux/kernel.h> +#include <linux/version.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/usb.h> +#include <linux/videodev2.h> +#include <linux/vmalloc.h> +#include <linux/wait.h> +#include <asm/atomic.h> +#include <asm/unaligned.h> + +#include <media/v4l2-common.h> + +#include "uvcvideo.h" + +/* ------------------------------------------------------------------------ + * UVC Controls + */ + +static int __uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit, + __u8 intfnum, __u8 cs, void *data, __u16 size, + int timeout) +{ + __u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE; + unsigned int pipe; + int ret; + + pipe = (query & 0x80) ? usb_rcvctrlpipe(dev->udev, 0) + : usb_sndctrlpipe(dev->udev, 0); + type |= (query & 0x80) ? USB_DIR_IN : USB_DIR_OUT; + + ret = usb_control_msg(dev->udev, pipe, query, type, cs << 8, + unit << 8 | intfnum, data, size, timeout); + + if (ret != size) { + uvc_printk(KERN_ERR, "Failed to query (%u) UVC control %u " + "(unit %u) : %d (exp. %u).\n", query, cs, unit, ret, + size); + return -EIO; + } + + return 0; +} + +int uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit, + __u8 intfnum, __u8 cs, void *data, __u16 size) +{ + return __uvc_query_ctrl(dev, query, unit, intfnum, cs, data, size, + UVC_CTRL_CONTROL_TIMEOUT); +} + +static void uvc_fixup_buffer_size(struct uvc_video_device *video, + struct uvc_streaming_control *ctrl) +{ + struct uvc_format *format; + struct uvc_frame *frame; + + if (ctrl->bFormatIndex <= 0 || + ctrl->bFormatIndex > video->streaming->nformats) + return; + + format = &video->streaming->format[ctrl->bFormatIndex - 1]; + + if (ctrl->bFrameIndex <= 0 || + ctrl->bFrameIndex > format->nframes) + return; + + frame = &format->frame[ctrl->bFrameIndex - 1]; + + if (!(format->flags & UVC_FMT_FLAG_COMPRESSED) || + (ctrl->dwMaxVideoFrameSize == 0 && + video->dev->uvc_version < 0x0110)) + ctrl->dwMaxVideoFrameSize = + frame->dwMaxVideoFrameBufferSize; +} + +static int uvc_get_video_ctrl(struct uvc_video_device *video, + struct uvc_streaming_control *ctrl, int probe, __u8 query) +{ + __u8 data[34]; + __u8 size; + int ret; + + size = video->dev->uvc_version >= 0x0110 ? 34 : 26; + ret = __uvc_query_ctrl(video->dev, query, 0, video->streaming->intfnum, + probe ? VS_PROBE_CONTROL : VS_COMMIT_CONTROL, &data, size, + UVC_CTRL_STREAMING_TIMEOUT); + + if (ret < 0) + return ret; + + ctrl->bmHint = le16_to_cpup((__le16 *)&data[0]); + ctrl->bFormatIndex = data[2]; + ctrl->bFrameIndex = data[3]; + ctrl->dwFrameInterval = le32_to_cpup((__le32 *)&data[4]); + ctrl->wKeyFrameRate = le16_to_cpup((__le16 *)&data[8]); + ctrl->wPFrameRate = le16_to_cpup((__le16 *)&data[10]); + ctrl->wCompQuality = le16_to_cpup((__le16 *)&data[12]); + ctrl->wCompWindowSize = le16_to_cpup((__le16 *)&data[14]); + ctrl->wDelay = le16_to_cpup((__le16 *)&data[16]); + ctrl->dwMaxVideoFrameSize = + le32_to_cpu(get_unaligned((__le32 *)&data[18])); + ctrl->dwMaxPayloadTransferSize = + le32_to_cpu(get_unaligned((__le32 *)&data[22])); + + if (size == 34) { + ctrl->dwClockFrequency = + le32_to_cpu(get_unaligned((__le32 *)&data[26])); + ctrl->bmFramingInfo = data[30]; + ctrl->bPreferedVersion = data[31]; + ctrl->bMinVersion = data[32]; + ctrl->bMaxVersion = data[33]; + } else { + ctrl->dwClockFrequency = video->dev->clock_frequency; + ctrl->bmFramingInfo = 0; + ctrl->bPreferedVersion = 0; + ctrl->bMinVersion = 0; + ctrl->bMaxVersion = 0; + } + + /* Some broken devices return a null or wrong dwMaxVideoFrameSize. + * Try to get the value from the format and frame descriptor. + */ + uvc_fixup_buffer_size(video, ctrl); + + return 0; +} + +int uvc_set_video_ctrl(struct uvc_video_device *video, + struct uvc_streaming_control *ctrl, int probe) +{ + __u8 data[34]; + __u8 size; + + size = video->dev->uvc_version >= 0x0110 ? 34 : 26; + memset(data, 0, sizeof data); + + *(__le16 *)&data[0] = cpu_to_le16(ctrl->bmHint); + data[2] = ctrl->bFormatIndex; + data[3] = ctrl->bFrameIndex; + *(__le32 *)&data[4] = cpu_to_le32(ctrl->dwFrameInterval); + *(__le16 *)&data[8] = cpu_to_le16(ctrl->wKeyFrameRate); + *(__le16 *)&data[10] = cpu_to_le16(ctrl->wPFrameRate); + *(__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(cpu_to_le32(ctrl->dwMaxVideoFrameSize), + (__le32 *)&data[18]); + put_unaligned(cpu_to_le32(ctrl->dwMaxPayloadTransferSize), + (__le32 *)&data[22]); + + if (size == 34) { + put_unaligned(cpu_to_le32(ctrl->dwClockFrequency), + (__le32 *)&data[26]); + data[30] = ctrl->bmFramingInfo; + data[31] = ctrl->bPreferedVersion; + data[32] = ctrl->bMinVersion; + data[33] = ctrl->bMaxVersion; + } + + return __uvc_query_ctrl(video->dev, SET_CUR, 0, + video->streaming->intfnum, + probe ? VS_PROBE_CONTROL : VS_COMMIT_CONTROL, &data, size, + UVC_CTRL_STREAMING_TIMEOUT); +} + +int uvc_probe_video(struct uvc_video_device *video, + struct uvc_streaming_control *probe) +{ + struct uvc_streaming_control probe_min, probe_max; + __u16 bandwidth; + unsigned int i; + int ret; + + mutex_lock(&video->streaming->mutex); + + /* Perform probing. The device should adjust the requested values + * according to its capabilities. However, some devices, namely the + * first generation UVC Logitech webcams, don't implement the Video + * Probe control properly, and just return the needed bandwidth. For + * that reason, if the needed bandwidth exceeds the maximum available + * bandwidth, try to lower the quality. + */ + if ((ret = uvc_set_video_ctrl(video, probe, 1)) < 0) + goto done; + + /* Get the minimum and maximum values for compression settings. */ + if (!(video->dev->quirks & UVC_QUIRK_PROBE_MINMAX)) { + ret = uvc_get_video_ctrl(video, &probe_min, 1, GET_MIN); + if (ret < 0) + goto done; + ret = uvc_get_video_ctrl(video, &probe_max, 1, GET_MAX); + if (ret < 0) + goto done; + + probe->wCompQuality = probe_max.wCompQuality; + } + + for (i = 0; i < 2; ++i) { + if ((ret = uvc_set_video_ctrl(video, probe, 1)) < 0 || + (ret = uvc_get_video_ctrl(video, probe, 1, GET_CUR)) < 0) + goto done; + + if (video->streaming->intf->num_altsetting == 1) + break; + + bandwidth = probe->dwMaxPayloadTransferSize; + if (bandwidth <= video->streaming->maxpsize) + break; + + if (video->dev->quirks & UVC_QUIRK_PROBE_MINMAX) { + ret = -ENOSPC; + goto done; + } + + /* TODO: negotiate compression parameters */ + probe->wKeyFrameRate = probe_min.wKeyFrameRate; + probe->wPFrameRate = probe_min.wPFrameRate; + probe->wCompQuality = probe_max.wCompQuality; + probe->wCompWindowSize = probe_min.wCompWindowSize; + } + +done: + mutex_unlock(&video->streaming->mutex); + return ret; +} + +/* ------------------------------------------------------------------------ + * Video codecs + */ + +/* Values for bmHeaderInfo (Video and Still Image Payload Headers, 2.4.3.3) */ +#define UVC_STREAM_EOH (1 << 7) +#define UVC_STREAM_ERR (1 << 6) +#define UVC_STREAM_STI (1 << 5) +#define UVC_STREAM_RES (1 << 4) +#define UVC_STREAM_SCR (1 << 3) +#define UVC_STREAM_PTS (1 << 2) +#define UVC_STREAM_EOF (1 << 1) +#define UVC_STREAM_FID (1 << 0) + +/* Video payload decoding is handled by uvc_video_decode_start(), + * uvc_video_decode_data() and uvc_video_decode_end(). + * + * uvc_video_decode_start is called with URB data at the start of a bulk or + * isochronous payload. It processes header data and returns the header size + * in bytes if successful. If an error occurs, it returns a negative error + * code. The following error codes have special meanings. + * + * - EAGAIN informs the caller that the current video buffer should be marked + * as done, and that the function should be called again with the same data + * and a new video buffer. This is used when end of frame conditions can be + * reliably detected at the beginning of the next frame only. + * + * If an error other than -EAGAIN is returned, the caller will drop the current + * payload. No call to uvc_video_decode_data and uvc_video_decode_end will be + * made until the next payload. -ENODATA can be used to drop the current + * payload if no other error code is appropriate. + * + * uvc_video_decode_data is called for every URB with URB data. It copies the + * data to the video buffer. + * + * uvc_video_decode_end is called with header data at the end of a bulk or + * isochronous payload. It performs any additional header data processing and + * returns 0 or a negative error code if an error occured. As header data have + * already been processed by uvc_video_decode_start, this functions isn't + * required to perform sanity checks a second time. + * + * For isochronous transfers where a payload is always transfered in a single + * URB, the three functions will be called in a row. + * + * To let the decoder process header data and update its internal state even + * when no video buffer is available, uvc_video_decode_start must be prepared + * to be called with a NULL buf parameter. uvc_video_decode_data and + * uvc_video_decode_end will never be called with a NULL buffer. + */ +static int uvc_video_decode_start(struct uvc_video_device *video, + struct uvc_buffer *buf, const __u8 *data, int len) +{ + __u8 fid; + + /* Sanity checks: + * - packet must be at least 2 bytes long + * - bHeaderLength value must be at least 2 bytes (see above) + * - bHeaderLength value can't be larger than the packet size. + */ + if (len < 2 || data[0] < 2 || data[0] > len) + return -EINVAL; + + /* Skip payloads marked with the error bit ("error frames"). */ + if (data[1] & UVC_STREAM_ERR) { + uvc_trace(UVC_TRACE_FRAME, "Dropping payload (error bit " + "set).\n"); + return -ENODATA; + } + + fid = data[1] & UVC_STREAM_FID; + + /* Store the payload FID bit and return immediately when the buffer is + * NULL. + */ + if (buf == NULL) { + video->last_fid = fid; + return -ENODATA; + } + + /* Synchronize to the input stream by waiting for the FID bit to be + * toggled when the the buffer state is not UVC_BUF_STATE_ACTIVE. + * queue->last_fid is initialized to -1, so the first isochronous + * frame will always be in sync. + * + * If the device doesn't toggle the FID bit, invert video->last_fid + * when the EOF bit is set to force synchronisation on the next packet. + */ + if (buf->state != UVC_BUF_STATE_ACTIVE) { + if (fid == video->last_fid) { + uvc_trace(UVC_TRACE_FRAME, "Dropping payload (out of " + "sync).\n"); + if ((video->dev->quirks & UVC_QUIRK_STREAM_NO_FID) && + (data[1] & UVC_STREAM_EOF)) + video->last_fid ^= UVC_STREAM_FID; + return -ENODATA; + } + + /* TODO: Handle PTS and SCR. */ + buf->state = UVC_BUF_STATE_ACTIVE; + } + + /* Mark the buffer as done if we're at the beginning of a new frame. + * End of frame detection is better implemented by checking the EOF + * bit (FID bit toggling is delayed by one frame compared to the EOF + * bit), but some devices don't set the bit at end of frame (and the + * last payload can be lost anyway). We thus must check if the FID has + * been toggled. + * + * queue->last_fid is initialized to -1, so the first isochronous + * frame will never trigger an end of frame detection. + * + * 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 + * previous payload had the EOF bit set. + */ + if (fid != video->last_fid && buf->buf.bytesused != 0) { + uvc_trace(UVC_TRACE_FRAME, "Frame complete (FID bit " + "toggled).\n"); + buf->state = UVC_BUF_STATE_DONE; + return -EAGAIN; + } + + video->last_fid = fid; + + return data[0]; +} + +static void uvc_video_decode_data(struct uvc_video_device *video, + struct uvc_buffer *buf, const __u8 *data, int len) +{ + struct uvc_video_queue *queue = &video->queue; + unsigned int maxlen, nbytes; + void *mem; + + if (len <= 0) + return; + + /* Copy the video data to the buffer. */ + maxlen = buf->buf.length - buf->buf.bytesused; + mem = queue->mem + buf->buf.m.offset + buf->buf.bytesused; + nbytes = min((unsigned int)len, maxlen); + memcpy(mem, data, nbytes); + buf->buf.bytesused += nbytes; + + /* Complete the current frame if the buffer size was exceeded. */ + if (len > maxlen) { + uvc_trace(UVC_TRACE_FRAME, "Frame complete (overflow).\n"); + buf->state = UVC_BUF_STATE_DONE; + } +} + +static void uvc_video_decode_end(struct uvc_video_device *video, + struct uvc_buffer *buf, const __u8 *data, int len) +{ + /* Mark the buffer as done if the EOF marker is set. */ + if (data[1] & UVC_STREAM_EOF && buf->buf.bytesused != 0) { + uvc_trace(UVC_TRACE_FRAME, "Frame complete (EOF found).\n"); + if (data[0] == len) + uvc_trace(UVC_TRACE_FRAME, "EOF in empty payload.\n"); + buf->state = UVC_BUF_STATE_DONE; + if (video->dev->quirks & UVC_QUIRK_STREAM_NO_FID) + video->last_fid ^= UVC_STREAM_FID; + } +} + +/* ------------------------------------------------------------------------ + * URB handling + */ + +/* + * Completion handler for video URBs. + */ +static void uvc_video_decode_isoc(struct urb *urb, + struct uvc_video_device *video, struct uvc_buffer *buf) +{ + u8 *mem; + int ret, i; + + for (i = 0; i < urb->number_of_packets; ++i) { + if (urb->iso_frame_desc[i].status < 0) { + uvc_trace(UVC_TRACE_FRAME, "USB isochronous frame " + "lost (%d).\n", urb->iso_frame_desc[i].status); + continue; + } + + /* Decode the payload header. */ + mem = urb->transfer_buffer + urb->iso_frame_desc[i].offset; + do { + ret = uvc_video_decode_start(video, buf, mem, + urb->iso_frame_desc[i].actual_length); + if (ret == -EAGAIN) + buf = uvc_queue_next_buffer(&video->queue, buf); + } while (ret == -EAGAIN); + + if (ret < 0) + continue; + + /* Decode the payload data. */ + uvc_video_decode_data(video, buf, mem + ret, + urb->iso_frame_desc[i].actual_length - ret); + + /* Process the header again. */ + uvc_video_decode_end(video, buf, mem, ret); + + if (buf->state == UVC_BUF_STATE_DONE || + buf->state == UVC_BUF_STATE_ERROR) + buf = uvc_queue_next_buffer(&video->queue, buf); + } +} + +static void uvc_video_decode_bulk(struct urb *urb, + struct uvc_video_device *video, struct uvc_buffer *buf) +{ + u8 *mem; + int len, ret; + + mem = urb->transfer_buffer; + len = urb->actual_length; + video->bulk.payload_size += len; + + /* If the URB is the first of its payload, decode and save the + * header. + */ + if (video->bulk.header_size == 0) { + do { + ret = uvc_video_decode_start(video, buf, mem, len); + if (ret == -EAGAIN) + buf = uvc_queue_next_buffer(&video->queue, buf); + } while (ret == -EAGAIN); + + /* If an error occured skip the rest of the payload. */ + if (ret < 0 || buf == NULL) { + video->bulk.skip_payload = 1; + return; + } + + video->bulk.header_size = ret; + memcpy(video->bulk.header, mem, video->bulk.header_size); + + mem += ret; + len -= ret; + } + + /* The buffer queue might have been cancelled while a bulk transfer + * was in progress, so we can reach here with buf equal to NULL. Make + * sure buf is never dereferenced if NULL. + */ + + /* Process video data. */ + if (!video->bulk.skip_payload && buf != NULL) + uvc_video_decode_data(video, buf, mem, len); + + /* Detect the payload end by a URB smaller than the maximum size (or + * a payload size equal to the maximum) and process the header again. + */ + if (urb->actual_length < urb->transfer_buffer_length || + video->bulk.payload_size >= video->bulk.max_payload_size) { + if (!video->bulk.skip_payload && buf != NULL) { + uvc_video_decode_end(video, buf, video->bulk.header, + video->bulk.header_size); + if (buf->state == UVC_BUF_STATE_DONE || + buf->state == UVC_BUF_STATE_ERROR) + buf = uvc_queue_next_buffer(&video->queue, buf); + } + + video->bulk.header_size = 0; + video->bulk.skip_payload = 0; + video->bulk.payload_size = 0; + } +} + +static void uvc_video_complete(struct urb *urb) +{ + struct uvc_video_device *video = urb->context; + struct uvc_video_queue *queue = &video->queue; + struct uvc_buffer *buf = NULL; + unsigned long flags; + int ret; + + switch (urb->status) { + case 0: + break; + + default: + uvc_printk(KERN_WARNING, "Non-zero status (%d) in video " + "completion handler.\n", urb->status); + + case -ENOENT: /* usb_kill_urb() called. */ + if (video->frozen) + return; + + case -ECONNRESET: /* usb_unlink_urb() called. */ + case -ESHUTDOWN: /* The endpoint is being disabled. */ + uvc_queue_cancel(queue, urb->status == -ESHUTDOWN); + return; + } + + spin_lock_irqsave(&queue->irqlock, flags); + if (!list_empty(&queue->irqqueue)) + buf = list_first_entry(&queue->irqqueue, struct uvc_buffer, + queue); + spin_unlock_irqrestore(&queue->irqlock, flags); + + video->decode(urb, video, buf); + + if ((ret = usb_submit_urb(urb, GFP_ATOMIC)) < 0) { + uvc_printk(KERN_ERR, "Failed to resubmit video URB (%d).\n", + ret); + } +} + +/* + * Uninitialize isochronous/bulk URBs and free transfer buffers. + */ +static void uvc_uninit_video(struct uvc_video_device *video) +{ + struct urb *urb; + unsigned int i; + + for (i = 0; i < UVC_URBS; ++i) { + if ((urb = video->urb[i]) == NULL) + continue; + + usb_kill_urb(urb); + /* urb->transfer_buffer_length is not touched by USB core, so + * we can use it here as the buffer length. + */ + if (video->urb_buffer[i]) { + usb_buffer_free(video->dev->udev, + urb->transfer_buffer_length, + video->urb_buffer[i], urb->transfer_dma); + video->urb_buffer[i] = NULL; + } + + usb_free_urb(urb); + video->urb[i] = NULL; + } +} + +/* + * Initialize isochronous URBs and allocate transfer buffers. The packet size + * is given by the endpoint. + */ +static int uvc_init_video_isoc(struct uvc_video_device *video, + struct usb_host_endpoint *ep) +{ + struct urb *urb; + unsigned int npackets, i, j; + __u16 psize; + __u32 size; + + /* Compute the number of isochronous packets to allocate by dividing + * the maximum video frame size by the packet size. Limit the result + * to UVC_MAX_ISO_PACKETS. + */ + psize = le16_to_cpu(ep->desc.wMaxPacketSize); + psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3)); + + size = video->streaming->ctrl.dwMaxVideoFrameSize; + if (size > UVC_MAX_FRAME_SIZE) + return -EINVAL; + + npackets = (size + psize - 1) / psize; + if (npackets > UVC_MAX_ISO_PACKETS) + npackets = UVC_MAX_ISO_PACKETS; + + size = npackets * psize; + + for (i = 0; i < UVC_URBS; ++i) { + urb = usb_alloc_urb(npackets, GFP_KERNEL); + if (urb == NULL) { + uvc_uninit_video(video); + return -ENOMEM; + } + + video->urb_buffer[i] = usb_buffer_alloc(video->dev->udev, + size, GFP_KERNEL, &urb->transfer_dma); + if (video->urb_buffer[i] == NULL) { + usb_free_urb(urb); + uvc_uninit_video(video); + return -ENOMEM; + } + + urb->dev = video->dev->udev; + urb->context = video; + urb->pipe = usb_rcvisocpipe(video->dev->udev, + ep->desc.bEndpointAddress); + urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; + urb->interval = ep->desc.bInterval; + urb->transfer_buffer = video->urb_buffer[i]; + urb->complete = uvc_video_complete; + urb->number_of_packets = npackets; + urb->transfer_buffer_length = size; + + for (j = 0; j < npackets; ++j) { + urb->iso_frame_desc[j].offset = j * psize; + urb->iso_frame_desc[j].length = psize; + } + + video->urb[i] = urb; + } + + return 0; +} + +/* + * Initialize bulk URBs and allocate transfer buffers. The packet size is + * given by the endpoint. + */ +static int uvc_init_video_bulk(struct uvc_video_device *video, + struct usb_host_endpoint *ep) +{ + struct urb *urb; + unsigned int pipe, i; + __u16 psize; + __u32 size; + + /* Compute the bulk URB size. Some devices set the maximum payload + * size to a value too high for memory-constrained devices. We must + * then transfer the payload accross multiple URBs. To be consistant + * with isochronous mode, allocate maximum UVC_MAX_ISO_PACKETS per bulk + * URB. + */ + psize = le16_to_cpu(ep->desc.wMaxPacketSize) & 0x07ff; + size = video->streaming->ctrl.dwMaxPayloadTransferSize; + video->bulk.max_payload_size = size; + if (size > psize * UVC_MAX_ISO_PACKETS) + size = psize * UVC_MAX_ISO_PACKETS; + + pipe = usb_rcvbulkpipe(video->dev->udev, ep->desc.bEndpointAddress); + + for (i = 0; i < UVC_URBS; ++i) { + urb = usb_alloc_urb(0, GFP_KERNEL); + if (urb == NULL) { + uvc_uninit_video(video); + return -ENOMEM; + } + + video->urb_buffer[i] = usb_buffer_alloc(video->dev->udev, + size, GFP_KERNEL, &urb->transfer_dma); + if (video->urb_buffer[i] == NULL) { + usb_free_urb(urb); + uvc_uninit_video(video); + return -ENOMEM; + } + + usb_fill_bulk_urb(urb, video->dev->udev, pipe, + video->urb_buffer[i], size, uvc_video_complete, + video); + urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP; + + video->urb[i] = urb; + } + + return 0; +} + +/* + * Initialize isochronous/bulk URBs and allocate transfer buffers. + */ +static int uvc_init_video(struct uvc_video_device *video) +{ + struct usb_interface *intf = video->streaming->intf; + struct usb_host_interface *alts; + struct usb_host_endpoint *ep = NULL; + int intfnum = video->streaming->intfnum; + unsigned int bandwidth, psize, i; + int ret; + + video->last_fid = -1; + video->bulk.header_size = 0; + video->bulk.skip_payload = 0; + video->bulk.payload_size = 0; + + if (intf->num_altsetting > 1) { + /* Isochronous endpoint, select the alternate setting. */ + bandwidth = video->streaming->ctrl.dwMaxPayloadTransferSize; + + if (bandwidth == 0) { + uvc_printk(KERN_WARNING, "device %s requested null " + "bandwidth, defaulting to lowest.\n", + video->vdev->name); + bandwidth = 1; + } + + for (i = 0; i < intf->num_altsetting; ++i) { + alts = &intf->altsetting[i]; + ep = uvc_find_endpoint(alts, + video->streaming->header.bEndpointAddress); + if (ep == NULL) + continue; + + /* Check if the bandwidth is high enough. */ + psize = le16_to_cpu(ep->desc.wMaxPacketSize); + psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3)); + if (psize >= bandwidth) + break; + } + + if (i >= intf->num_altsetting) + return -EIO; + + if ((ret = usb_set_interface(video->dev->udev, intfnum, i)) < 0) + return ret; + + ret = uvc_init_video_isoc(video, ep); + } else { + /* Bulk endpoint, proceed to URB initialization. */ + ep = uvc_find_endpoint(&intf->altsetting[0], + video->streaming->header.bEndpointAddress); + if (ep == NULL) + return -EIO; + + ret = uvc_init_video_bulk(video, ep); + } + + if (ret < 0) + return ret; + + /* Submit the URBs. */ + for (i = 0; i < UVC_URBS; ++i) { + if ((ret = usb_submit_urb(video->urb[i], GFP_KERNEL)) < 0) { + uvc_printk(KERN_ERR, "Failed to submit URB %u " + "(%d).\n", i, ret); + uvc_uninit_video(video); + return ret; + } + } + + return 0; +} + +/* -------------------------------------------------------------------------- + * Suspend/resume + */ + +/* + * Stop streaming without disabling the video queue. + * + * To let userspace applications resume without trouble, we must not touch the + * video buffers in any way. We mark the device as frozen to make sure the URB + * completion handler won't try to cancel the queue when we kill the URBs. + */ +int uvc_video_suspend(struct uvc_video_device *video) +{ + if (!uvc_queue_streaming(&video->queue)) + return 0; + + video->frozen = 1; + uvc_uninit_video(video); + usb_set_interface(video->dev->udev, video->streaming->intfnum, 0); + return 0; +} + +/* + * Reconfigure the video interface and restart streaming if it was enable + * before suspend. + * + * If an error occurs, disable the video queue. This will wake all pending + * buffers, making sure userspace applications are notified of the problem + * instead of waiting forever. + */ +int uvc_video_resume(struct uvc_video_device *video) +{ + int ret; + + video->frozen = 0; + + if ((ret = uvc_set_video_ctrl(video, &video->streaming->ctrl, 0)) < 0) { + uvc_queue_enable(&video->queue, 0); + return ret; + } + + if (!uvc_queue_streaming(&video->queue)) + return 0; + + if ((ret = uvc_init_video(video)) < 0) + uvc_queue_enable(&video->queue, 0); + + return ret; +} + +/* ------------------------------------------------------------------------ + * Video device + */ + +/* + * Initialize the UVC video device by retrieving the default format and + * committing it. + * + * Some cameras (namely the Fuji Finepix) set the format and frame + * indexes to zero. The UVC standard doesn't clearly make this a spec + * violation, so try to silently fix the values if possible. + * + * This function is called before registering the device with V4L. + */ +int uvc_video_init(struct uvc_video_device *video) +{ + struct uvc_streaming_control *probe = &video->streaming->ctrl; + struct uvc_format *format = NULL; + struct uvc_frame *frame = NULL; + unsigned int i; + int ret; + + if (video->streaming->nformats == 0) { + uvc_printk(KERN_INFO, "No supported video formats found.\n"); + return -EINVAL; + } + + /* Alternate setting 0 should be the default, yet the XBox Live Vision + * Cam (and possibly other devices) crash or otherwise misbehave if + * they don't receive a SET_INTERFACE request before any other video + * control request. + */ + usb_set_interface(video->dev->udev, video->streaming->intfnum, 0); + + /* Some webcams don't suport GET_DEF request 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 && + (ret = uvc_get_video_ctrl(video, probe, 1, GET_CUR)) < 0) + return ret; + + /* Check if the default format descriptor exists. Use the first + * available format otherwise. + */ + for (i = video->streaming->nformats; i > 0; --i) { + format = &video->streaming->format[i-1]; + if (format->index == probe->bFormatIndex) + break; + } + + if (format->nframes == 0) { + uvc_printk(KERN_INFO, "No frame descriptor found for the " + "default format.\n"); + return -EINVAL; + } + + /* Zero bFrameIndex might be correct. Stream-based formats (including + * MPEG-2 TS and DV) do not support frames but have a dummy frame + * descriptor with bFrameIndex set to zero. If the default frame + * descriptor is not found, use the first avalable frame. + */ + for (i = format->nframes; i > 0; --i) { + frame = &format->frame[i-1]; + if (frame->bFrameIndex == probe->bFrameIndex) + break; + } + + /* Commit the default settings. */ + probe->bFormatIndex = format->index; + probe->bFrameIndex = frame->bFrameIndex; + if ((ret = uvc_set_video_ctrl(video, probe, 0)) < 0) + return ret; + + video->streaming->cur_format = format; + video->streaming->cur_frame = frame; + atomic_set(&video->active, 0); + + /* Select the video decoding function */ + if (video->dev->quirks & UVC_QUIRK_BUILTIN_ISIGHT) + video->decode = uvc_video_decode_isight; + else if (video->streaming->intf->num_altsetting > 1) + video->decode = uvc_video_decode_isoc; + else + video->decode = uvc_video_decode_bulk; + + return 0; +} + +/* + * Enable or disable the video stream. + */ +int uvc_video_enable(struct uvc_video_device *video, int enable) +{ + int ret; + + if (!enable) { + uvc_uninit_video(video); + usb_set_interface(video->dev->udev, + video->streaming->intfnum, 0); + uvc_queue_enable(&video->queue, 0); + return 0; + } + + if ((ret = uvc_queue_enable(&video->queue, 1)) < 0) + return ret; + + return uvc_init_video(video); +} |
