/* * uvc_video.c -- USB Video Class driver - Video handling * * Copyright (C) 2005-2010 * Laurent Pinchart (laurent.pinchart@ideasonboard.com) * * 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 #include #include #include #include #include #include #include #include #include #include #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; pipe = (query & 0x80) ? usb_rcvctrlpipe(dev->udev, 0) : usb_sndctrlpipe(dev->udev, 0); type |= (query & 0x80) ? USB_DIR_IN : USB_DIR_OUT; return usb_control_msg(dev->udev, pipe, query, type, cs << 8, unit << 8 | intfnum, data, size, timeout); } static const char *uvc_query_name(__u8 query) { switch (query) { case UVC_SET_CUR: return "SET_CUR"; case UVC_GET_CUR: return "GET_CUR"; case UVC_GET_MIN: return "GET_MIN"; case UVC_GET_MAX: return "GET_MAX"; case UVC_GET_RES: return "GET_RES"; case UVC_GET_LEN: return "GET_LEN"; case UVC_GET_INFO: return "GET_INFO"; case UVC_GET_DEF: return "GET_DEF"; default: return ""; } } int uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit, __u8 intfnum, __u8 cs, void *data, __u16 size) { int ret; ret = __uvc_query_ctrl(dev, query, unit, intfnum, cs, data, size, UVC_CTRL_CONTROL_TIMEOUT); if (ret != size) { uvc_printk(KERN_ERR, "Failed to query (%s) UVC control %u on " "unit %u: %d (exp. %u).\n", uvc_query_name(query), cs, unit, ret, size); return -EIO; } return 0; } static void uvc_fixup_video_ctrl(struct uvc_streaming *stream, struct uvc_streaming_control *ctrl) { struct uvc_format *format; struct uvc_frame *frame = NULL; unsigned int i; if (ctrl->bFormatIndex <= 0 || ctrl->bFormatIndex > stream->nformats) return; format = &stream->format[ctrl->bFormatIndex - 1]; for (i = 0; i < format->nframes; ++i) { if (format->frame[i].bFrameIndex == ctrl->bFrameIndex) { frame = &format->frame[i]; break; } } if (frame == NULL) return; if (!(format->flags & UVC_FMT_FLAG_COMPRESSED) || (ctrl->dwMaxVideoFrameSize == 0 && stream->dev->uvc_version < 0x0110)) ctrl->dwMaxVideoFrameSize = frame->dwMaxVideoFrameBufferSize; if (!(format->flags & UVC_FMT_FLAG_COMPRESSED) && stream->dev->quirks & UVC_QUIRK_FIX_BANDWIDTH && stream->intf->num_altsetting > 1) { u32 interval; u32 bandwidth; interval = (ctrl->dwFrameInterval > 100000) ? ctrl->dwFrameInterval : frame->dwFrameInterval[0]; /* Compute a bandwidth estimation by multiplying the frame * size by the number of video frames per second, divide the * result by the number of USB frames (or micro-frames for * high-speed devices) per second and add the UVC header size * (assumed to be 12 bytes long). */ bandwidth = frame->wWidth * frame->wHeight / 8 * format->bpp; bandwidth *= 10000000 / interval + 1; bandwidth /= 1000; if (stream->dev->udev->speed == USB_SPEED_HIGH) bandwidth /= 8; bandwidth += 12; /* The bandwidth estimate is too low for many cameras. Don't use * maximum packet sizes lower than 1024 bytes to try and work * around the problem. According to measurements done on two * different camera models, the value is high enough to get most * resolutions working while not preventing two simultaneous * VGA streams at 15 fps. */ bandwidth = max_t(u32, bandwidth, 1024); ctrl->dwMaxPayloadTransferSize = bandwidth; } } static int uvc_get_video_ctrl(struct uvc_streaming *stream, struct uvc_streaming_control *ctrl, int probe, __u8 query) { __u8 *data; __u16 size; int ret; size = stream->dev->uvc_version >= 0x0110 ? 34 : 26; if ((stream->dev->quirks & UVC_QUIRK_PROBE_DEF) && query == UVC_GET_DEF) return -EIO; data = kmalloc(size, GFP_KERNEL); if (data == NULL) return -ENOMEM; ret = __uvc_query_ctrl(stream->dev, query, 0, stream->intfnum, probe ? UVC_VS_PROBE_CONTROL : UVC_VS_COMMIT_CONTROL, data, size, uvc_timeout_param); if ((query == UVC_GET_MIN || query == UVC_GET_MAX) && ret == 2) { /* Some cameras, mostly based on Bison Electronics chipsets, * answer a GET_MIN or GET_MAX request with the wCompQuality * field only. */ uvc_warn_once(stream->dev, UVC_WARN_MINMAX, "UVC non " "compliance - GET_MIN/MAX(PROBE) incorrectly " "supported. Enabling workaround.\n"); memset(ctrl, 0, sizeof *ctrl); ctrl->wCompQuality = le16_to_cpup((__le16 *)data); ret = 0; goto out; } else if (query == UVC_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. */ uvc_warn_once(stream->dev, UVC_WARN_PROBE_DEF, "UVC non " "compliance - GET_DEF(PROBE) not supported. " "Enabling workaround.\n"); ret = -EIO; goto out; } else if (ret != size) { uvc_printk(KERN_ERR, "Failed to query (%u) UVC %s control : " "%d (exp. %u).\n", query, probe ? "probe" : "commit", ret, size); ret = -EIO; goto out; } 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 = get_unaligned_le32(&data[18]); ctrl->dwMaxPayloadTransferSize = get_unaligned_le32(&data[22]); if (size == 34) { ctrl->dwClockFrequency = get_unaligned_le32(&data[26]); ctrl->bmFramingInfo = data[30]; ctrl->bPreferedVersion = data[31]; ctrl->bMinVersion = data[32]; ctrl->bMaxVersion = data[33]; } else { ctrl->dwClockFrequency = stream->dev->clock_frequency; ctrl->bmFramingInfo = 0; ctrl->bPreferedVersion = 0; ctrl->bMinVersion = 0; ctrl->bMaxVersion = 0; } /* Some broken devices return null or wrong dwMaxVideoFrameSize and * dwMaxPayloadTransferSize fields. Try to get the value from the * format and frame descriptors. */ uvc_fixup_video_ctrl(stream, ctrl); ret = 0; out: kfree(data); return ret; } static int uvc_set_video_ctrl(struct uvc_streaming *stream, struct uvc_streaming_control *ctrl, int probe) { __u8 *data; __u16 size; int ret; size = stream->dev->uvc_version >= 0x0110 ? 34 : 26; data = kzalloc(size, GFP_KERNEL); if (data == NULL) return -ENOMEM; *(__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); put_unaligned_le32(ctrl->dwMaxVideoFrameSize, &data[18]); put_unaligned_le32(ctrl->dwMaxPayloadTransferSize, &data[22]); if (size == 34) { put_unaligned_le32(ctrl->dwClockFrequency, &data[26]); data[30] = ctrl->bmFramingInfo; data[31] = ctrl->bPreferedVersion; data[32] = ctrl->bMinVersion; data[33] = ctrl->bMaxVersion; } ret = __uvc_query_ctrl(stream->dev, UVC_SET_CUR, 0, stream->intfnum, probe ? UVC_VS_PROBE_CONTROL : UVC_VS_COMMIT_CONTROL, data, size, uvc_timeout_param); if (ret != size) { uvc_printk(KERN_ERR, "Failed to set UVC %s control : " "%d (exp. %u).\n", probe ? "probe" : "commit", ret, size); ret = -EIO; } kfree(data); return ret; } int uvc_probe_video(struct uvc_streaming *stream, struct uvc_streaming_control *probe) { struct uvc_streaming_control probe_min, probe_max; __u16 bandwidth; unsigned int i; int ret; /* 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. */ ret = uvc_set_video_ctrl(stream, probe, 1); if (ret < 0) goto done; /* Get the minimum and maximum values for compression settings. */ if (!(stream->dev->quirks & UVC_QUIRK_PROBE_MINMAX)) { ret = uvc_get_video_ctrl(stream, &probe_min, 1, UVC_GET_MIN); if (ret < 0) goto done; ret = uvc_get_video_ctrl(stream, &probe_max, 1, UVC_GET_MAX); if (ret < 0) goto done; probe->wCompQuality = probe_max.wCompQuality; } for (i = 0; i < 2; ++i) { ret = uvc_set_video_ctrl(stream, probe, 1); if (ret < 0) goto done; ret = uvc_get_video_ctrl(stream, probe, 1, UVC_GET_CUR); if (ret < 0) goto done; if (stream->intf->num_altsetting == 1) break; bandwidth = probe->dwMaxPayloadTransferSize; if (bandwidth <= stream->maxpsize) break; if (stream->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: return ret; } int uvc_commit_video(struct uvc_streaming *stream, struct uvc_streaming_control *probe) { return uvc_set_video_ctrl(stream, probe, 0); } /* ------------------------------------------------------------------------ * 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_streaming *stream, 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; /* Increase the sequence number regardless of any buffer states, so * that discontinuous sequence numbers always indicate lost frames. */ if (stream->last_fid != fid) stream->sequence++; /* Store the payload FID bit and return immediately when the buffer is * NULL. */ if (buf == NULL) { stream->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. * stream->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 stream->last_fid * when the EOF bit is set to force synchronisation on the next packet. */ if (buf->state != UVC_BUF_STATE_ACTIVE) { struct timespec ts; if (fid == stream->last_fid) { uvc_trace(UVC_TRACE_FRAME, "Dropping payload (out of " "sync).\n"); if ((stream->dev->quirks & UVC_QUIRK_STREAM_NO_FID) && (data[1] & UVC_STREAM_EOF)) stream->last_fid ^= UVC_STREAM_FID; return -ENODATA; } if (uvc_clock_param == CLOCK_MONOTONIC) ktime_get_ts(&ts); else ktime_get_real_ts(&ts); buf->buf.sequence = stream->sequence; buf->buf.timestamp.tv_sec = ts.tv_sec; buf->buf.timestamp.tv_usec = ts.tv_nsec / NSEC_PER_USEC; /* 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. * * stream->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 end of frame conditions at FID toggling if the * previous payload had the EOF bit set. */ if (fid != stream->last_fid && buf->buf.bytesused != 0) { uvc_trace(UVC_TRACE_FRAME, "Frame complete (FID bit " "toggled).\n"); buf->state = UVC_BUF_STATE_READY; return -EAGAIN; } stream->last_fid = fid; return data[0]; } static void uvc_video_decode_data(struct uvc_streaming *stream, struct uvc_buffer *buf, const __u8 *data, int len) { struct uvc_video_queue *queue = &stream->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_READY; } } static void uvc_video_decode_end(struct uvc_streaming *stream, 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_READY; if (stream->dev->quirks & UVC_QUIRK_STREAM_NO_FID) stream->last_fid ^= UVC_STREAM_FID; } } /* 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_streaming *stream, struct uvc_buffer *buf, __u8 *data, int len) { data[0] = 2; /* Header length */ data[1] = UVC_STREAM_EOH | UVC_STREAM_EOF | (stream->last_fid & UVC_STREAM_FID); return 2; } static int uvc_video_encode_data(struct uvc_streaming *stream, struct uvc_buffer *buf, __u8 *data, int len) { struct uvc_video_queue *queue = &stream->queue; unsigned int nbytes; void *mem; /* Copy video data to the URB buffer. */ mem = queue->mem + buf->buf.m.offset + queue->buf_used; nbytes = min((unsigned int)len, buf->buf.bytesused - queue->buf_used); nbytes = min(stream->bulk.max_payload_size - stream->bulk.payload_size, nbytes); memcpy(data, mem, nbytes); queue->buf_used += nbytes; return nbytes; } /* ------------------------------------------------------------------------ * URB handling */ /* * Completion handler for video URBs. */ static void uvc_video_decode_isoc(struct urb *urb, struct uvc_streaming *stream, 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); /* Mark the buffer as faulty. */ if (buf != NULL) buf->error = 1; continue; } /* Decode the payload header. */ mem = urb->transfer_buffer + urb->iso_frame_desc[i].offset; do { ret = uvc_video_decode_start(stream, buf, mem, urb->iso_frame_desc[i].actual_length); if (ret == -EAGAIN) buf = uvc_queue_next_buffer(&stream->queue, buf); } while (ret == -EAGAIN); if (ret < 0) continue; /* Decode the payload data. */ uvc_video_decode_data(stream, buf, mem + ret, urb->iso_frame_desc[i].actual_length - ret); /* Process the header again. */ uvc_video_decode_end(stream, buf, mem, urb->iso_frame_desc[i].actual_length); if (buf->state == UVC_BUF_STATE_READY) { if (buf->buf.length != buf->buf.bytesused && !(stream->cur_format->flags & UVC_FMT_FLAG_COMPRESSED)) buf->error = 1; buf = uvc_queue_next_buffer(&stream->queue, buf); } } } static void uvc_video_decode_bulk(struct urb *urb, struct uvc_streaming *stream, struct uvc_buffer *buf) { u8 *mem; int len, ret; if (urb->actual_length == 0) return; mem = urb->transfer_buffer; len = urb->actual_length; stream->bulk.payload_size += len; /* If the URB is the first of its payload, decode and save the * header. */ if (stream->bulk.header_size == 0 && !stream->bulk.skip_payload) { do { ret = uvc_video_decode_start(stream, buf, mem, len); if (ret == -EAGAIN) buf = uvc_queue_next_buffer(&stream->queue, buf); } while (ret == -EAGAIN); /* If an error occured skip the rest of the payload. */ if (ret < 0 || buf == NULL) { stream->bulk.skip_payload = 1; } else { memcpy(stream->bulk.header, mem, ret); stream->bulk.header_size = ret; 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 (!stream->bulk.skip_payload && buf != NULL) uvc_video_decode_data(stream, 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 || stream->bulk.payload_size >= stream->bulk.max_payload_size) { if (!stream->bulk.skip_payload && buf != NULL) { uvc_video_decode_end(stream, buf, stream->bulk.header, stream->bulk.payload_size); if (buf->state == UVC_BUF_STATE_READY) buf = uvc_queue_next_buffer(&stream->queue, buf); } stream->bulk.header_size = 0; stream->bulk.skip_payload = 0; stream->bulk.payload_size = 0; } } static void uvc_video_encode_bulk(struct urb *urb, struct uvc_streaming *stream, struct uvc_buffer *buf) { u8 *mem = urb->transfer_buffer; int len = stream->urb_size, ret; if (buf == NULL) { urb->transfer_buffer_length = 0; return; } /* If the URB is the first of its payload, add the header. */ if (stream->bulk.header_size == 0) { ret = uvc_video_encode_header(stream, buf, mem, len); stream->bulk.header_size = ret; stream->bulk.payload_size += ret; mem += ret; len -= ret; } /* Process video data. */ ret = uvc_video_encode_data(stream, buf, mem, len); stream->bulk.payload_size += ret; len -= ret; if (buf->buf.bytesused == stream->queue.buf_used || stream->bulk.payload_size == stream->bulk.max_payload_size) { if (buf->buf.bytesused == stream->queue.buf_used) { stream->queue.buf_used = 0; buf->state = UVC_BUF_STATE_READY; buf->buf.sequence = ++stream->sequence; uvc_queue_next_buffer(&stream->queue, buf); stream->last_fid ^= UVC_STREAM_FID; } stream->bulk.header_size = 0; stream->bulk.payload_size = 0; } urb->transfer_buffer_length = stream->urb_size - len; } static void uvc_video_complete(struct urb *urb) { struct uvc_streaming *stream = urb->context; struct uvc_video_queue *queue = &stream->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 (stream->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); stream->decode(urb, stream, buf); if ((ret = usb_submit_urb(urb, GFP_ATOMIC)) < 0) { uvc_printk(KERN_ERR, "Failed to resubmit video URB (%d).\n", ret); } } /* * Free transfer buffers. */ static void uvc_free_urb_buffers(struct uvc_streaming *stream) { unsigned int i; for (i = 0; i < UVC_URBS; ++i) { if (stream->urb_buffer[i]) { usb_free_coherent(stream->dev->udev, stream->urb_size, stream->urb_buffer[i], stream->urb_dma[i]); stream->urb_buffer[i] = NULL; } } stream->urb_size = 0; } /* * Allocate transfer buffers. This function can be called with buffers * already allocated when resuming from suspend, in which case it will * return without touching the buffers. * * Limit the buffer size to UVC_MAX_PACKETS bulk/isochronous packets. If the * system is too low on memory try successively smaller numbers of packets * until allocation succeeds. * * Return the number of allocated packets on success or 0 when out of memory. */ static int uvc_alloc_urb_buffers(struct uvc_streaming *stream, unsigned int size, unsigned int psize, gfp_t gfp_flags) { unsigned int npackets; unsigned int i; /* Buffers are already allocated, bail out. */ if (stream->urb_size) return stream->urb_size / psize; /* Compute the number of packets. Bulk endpoints might transfer UVC * payloads accross multiple URBs. */ npackets = DIV_ROUND_UP(size, psize); if (npackets > UVC_MAX_PACKETS) npackets = UVC_MAX_PACKETS; /* Retry allocations until one succeed. */ for (; npackets > 1; npackets /= 2) { for (i = 0; i < UVC_URBS; ++i) { stream->urb_size = psize * npackets; stream->urb_buffer[i] = usb_alloc_coherent( stream->dev->udev, stream->urb_size, gfp_flags | __GFP_NOWARN, &stream->urb_dma[i]); if (!stream->urb_buffer[i]) { uvc_free_urb_buffers(stream); break; } } if (i == UVC_URBS) { uvc_trace(UVC_TRACE_VIDEO, "Allocated %u URB buffers " "of %ux%u bytes each.\n", UVC_URBS, npackets, psize); return npackets; } } uvc_trace(UVC_TRACE_VIDEO, "Failed to allocate URB buffers (%u bytes " "per packet).\n", psize); return 0; } /* * Uninitialize isochronous/bulk URBs and free transfer buffers. */ static void uvc_uninit_video(struct uvc_streaming *stream, int free_buffers) { struct urb *urb; unsigned int i; for (i = 0; i < UVC_URBS; ++i) { urb = stream->urb[i]; if (urb == NULL) continue; usb_kill_urb(urb); usb_free_urb(urb); stream->urb[i] = NULL; } if (free_buffers) uvc_free_urb_buffers(stream); } /* * Initialize isochronous URBs and allocate transfer buffers. The packet size * is given by the endpoint. */ static int uvc_init_video_isoc(struct uvc_streaming *stream, struct usb_host_endpoint *ep, gfp_t gfp_flags) { struct urb *urb; unsigned int npackets, i, j; u16 psize; u32 size; psize = le16_to_cpu(ep->desc.wMaxPacketSize); psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3)); size = stream->ctrl.dwMaxVideoFrameSize; npackets = uvc_alloc_urb_buffers(stream, size, psize, gfp_flags); if (npackets == 0) return -ENOMEM; size = npackets * psize; for (i = 0; i < UVC_URBS; ++i) { urb = usb_alloc_urb(npackets, gfp_flags); if (urb == NULL) { uvc_uninit_video(stream, 1); return -ENOMEM; } urb->dev = stream->dev->udev; urb->context = stream; urb->pipe = usb_rcvisocpipe(stream->dev->udev, ep->desc.bEndpointAddress); urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; urb->interval = ep->desc.bInterval; urb->transfer_buffer = stream->urb_buffer[i]; urb->transfer_dma = stream->urb_dma[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; } stream->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_streaming *stream, struct usb_host_endpoint *ep, gfp_t gfp_flags) { struct urb *urb; unsigned int npackets, pipe, i; u16 psize; u32 size; psize = le16_to_cpu(ep->desc.wMaxPacketSize) & 0x07ff; size = stream->ctrl.dwMaxPayloadTransferSize; stream->bulk.max_payload_size = size; npackets = uvc_alloc_urb_buffers(stream, size, psize, gfp_flags); if (npackets == 0) return -ENOMEM; size = npackets * psize; if (usb_endpoint_dir_in(&ep->desc)) pipe = usb_rcvbulkpipe(stream->dev->udev, ep->desc.bEndpointAddress); else pipe = usb_sndbulkpipe(stream->dev->udev, ep->desc.bEndpointAddress); if (stream->type == V4L2_BUF_TYPE_VIDEO_OUTPUT) size = 0; for (i = 0; i < UVC_URBS; ++i) { urb = usb_alloc_urb(0, gfp_flags); if (urb == NULL) { uvc_uninit_video(stream, 1); return -ENOMEM; } usb_fill_bulk_urb(urb, stream->dev->udev, pipe, stream->urb_buffer[i], size, uvc_video_complete, stream); urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP; urb->transfer_dma = stream->urb_dma[i]; stream->urb[i] = urb; } return 0; } /* * Initialize isochronous/bulk URBs and allocate transfer buffers. */ static int uvc_init_video(struct uvc_streaming *stream, gfp_t gfp_flags) { struct usb_interface *intf = stream->intf; struct usb_host_endpoint *ep; unsigned int i; int ret; stream->sequence = -1; stream->last_fid = -1; stream->bulk.header_size = 0; stream->bulk.skip_payload = 0; stream->bulk.payload_size = 0; if (intf->num_altsetting > 1) { struct usb_host_endpoint *best_ep = NULL; unsigned int best_psize = 3 * 1024; unsigned int bandwidth; unsigned int uninitialized_var(altsetting); int intfnum = stream->intfnum; /* Isochronous endpoint, select the alternate setting. */ bandwidth = stream->ctrl.dwMaxPayloadTransferSize; if (bandwidth == 0) { uvc_trace(UVC_TRACE_VIDEO, "Device requested null " "bandwidth, defaulting to lowest.\n"); bandwidth = 1; } else { uvc_trace(UVC_TRACE_VIDEO, "Device requested %u " "B/frame bandwidth.\n", bandwidth); } for (i = 0; i < intf->num_altsetting; ++i) { struct usb_host_interface *alts; unsigned int psize; alts = &intf->altsetting[i]; ep = uvc_find_endpoint(alts, stream->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 && psize <= best_psize) { altsetting = i; best_psize = psize; best_ep = ep; } } if (best_ep == NULL) { uvc_trace(UVC_TRACE_VIDEO, "No fast enough alt setting " "for requested bandwidth.\n"); return -EIO; } uvc_trace(UVC_TRACE_VIDEO, "Selecting alternate setting %u " "(%u B/frame bandwidth).\n", altsetting, best_psize); ret = usb_set_interface(stream->dev->udev, intfnum, altsetting); if (ret < 0) return ret; ret = uvc_init_video_isoc(stream, best_ep, gfp_flags); } else { /* Bulk endpoint, proceed to URB initialization. */ ep = uvc_find_endpoint(&intf->altsetting[0], stream->header.bEndpointAddress); if (ep == NULL) return -EIO; ret = uvc_init_video_bulk(stream, ep, gfp_flags); } if (ret < 0) return ret; /* Submit the URBs. */ for (i = 0; i < UVC_URBS; ++i) { ret = usb_submit_urb(stream->urb[i], gfp_flags); if (ret < 0) { uvc_printk(KERN_ERR, "Failed to submit URB %u " "(%d).\n", i, ret); uvc_uninit_video(stream, 1); 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_streaming *stream) { if (!uvc_queue_streaming(&stream->queue)) return 0; stream->frozen = 1; uvc_uninit_video(stream, 0); usb_set_interface(stream->dev->udev, stream->intfnum, 0); return 0; } /* * 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 * buffers, making sure userspace applications are notified of the problem * instead of waiting forever. */ int uvc_video_resume(struct uvc_streaming *stream) { int ret; stream->frozen = 0; ret = uvc_commit_video(stream, &stream->ctrl); if (ret < 0) { uvc_queue_enable(&stream->queue, 0); return ret; } if (!uvc_queue_streaming(&stream->queue)) return 0; ret = uvc_init_video(stream, GFP_NOIO); if (ret < 0) uvc_queue_enable(&stream->queue, 0); return ret; } /* ------------------------------------------------------------------------ * Video device */ /* * 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 * 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_streaming *stream) { struct uvc_streaming_control *probe = &stream->ctrl; struct uvc_format *format = NULL; struct uvc_frame *frame = NULL; unsigned int i; int ret; if (stream->nformats == 0) { uvc_printk(KERN_INFO, "No supported video formats found.\n"); return -EINVAL; } atomic_set(&stream->active, 0); /* Initialize the video buffers queue. */ uvc_queue_init(&stream->queue, stream->type, !uvc_no_drop_param); /* 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(stream->dev->udev, stream->intfnum, 0); /* Set the streaming probe control with default streaming parameters * retrieved from the device. Webcams that don't suport GET_DEF * requests on the probe control will just keep their current streaming * parameters. */ if (uvc_get_video_ctrl(stream, probe, 1, UVC_GET_DEF) == 0) uvc_set_video_ctrl(stream, probe, 1); /* Initialize the streaming parameters with the probe control current * value. This makes sure SET_CUR requests on the streaming commit * control will always use values retrieved from a successful GET_CUR * request on the probe control, as required by the UVC specification. */ ret = uvc_get_video_ctrl(stream, probe, 1, UVC_GET_CUR); if (ret < 0) return ret; /* Check if the default format descriptor exists. Use the first * available format otherwise. */ for (i = stream->nformats; i > 0; --i) { format = &stream->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 available frame. */ for (i = format->nframes; i > 0; --i) { frame = &format->frame[i-1]; if (frame->bFrameIndex == probe->bFrameIndex) break; } probe->bFormatIndex = format->index; probe->bFrameIndex = frame->bFrameIndex; stream->cur_format = format; stream->cur_frame = frame; /* Select the video decoding function */ if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) { if (stream->dev->quirks & UVC_QUIRK_BUILTIN_ISIGHT) stream->decode = uvc_video_decode_isight; else if (stream->intf->num_altsetting > 1) stream->decode = uvc_video_decode_isoc; else stream->decode = uvc_video_decode_bulk; } else { if (stream->intf->num_altsetting == 1) stream->decode = uvc_video_encode_bulk; else { uvc_printk(KERN_INFO, "Isochronous endpoints are not " "supported for video output devices.\n"); return -EINVAL; } } return 0; } /* * Enable or disable the video stream. */ int uvc_video_enable(struct uvc_streaming *stream, int enable) { int ret; if (!enable) { uvc_uninit_video(stream, 1); usb_set_interface(stream->dev->udev, stream->intfnum, 0); uvc_queue_enable(&stream->queue, 0); return 0; } ret = uvc_queue_enable(&stream->queue, 1); if (ret < 0) return ret; /* Commit the streaming parameters. */ ret = uvc_commit_video(stream, &stream->ctrl); if (ret < 0) return ret; return uvc_init_video(stream, GFP_KERNEL); }