return 0;
}
-static void uvc_fixup_buffer_size(struct uvc_video_device *video,
+static void uvc_fixup_video_ctrl(struct uvc_video_device *video,
struct uvc_streaming_control *ctrl)
{
struct uvc_format *format;
video->dev->uvc_version < 0x0110))
ctrl->dwMaxVideoFrameSize =
frame->dwMaxVideoFrameBufferSize;
+
+ if (video->dev->quirks & UVC_QUIRK_FIX_BANDWIDTH &&
+ video->streaming->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 (video->dev->udev->speed == USB_SPEED_HIGH)
+ bandwidth /= 8;
+ bandwidth += 12;
+
+ ctrl->dwMaxPayloadTransferSize = bandwidth;
+ }
}
static int uvc_get_video_ctrl(struct uvc_video_device *video,
ctrl->bMaxVersion = 0;
}
- /* Some broken devices return a null or wrong dwMaxVideoFrameSize.
- * Try to get the value from the format and frame descriptors.
+ /* Some broken devices return null or wrong dwMaxVideoFrameSize and
+ * dwMaxPayloadTransferSize fields. Try to get the value from the
+ * format and frame descriptors.
*/
- uvc_fixup_buffer_size(video, ctrl);
+ uvc_fixup_video_ctrl(video, ctrl);
ret = 0;
out:
u8 *mem;
int len, ret;
+ if (urb->actual_length == 0)
+ return;
+
mem = urb->transfer_buffer;
len = urb->actual_length;
video->bulk.payload_size += len;
* already allocated when resuming from suspend, in which case it will
* return without touching the buffers.
*
- * Return 0 on success or -ENOMEM when out of memory.
+ * 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_video_device *video,
- unsigned int size)
+ unsigned int size, unsigned int psize, gfp_t gfp_flags)
{
+ unsigned int npackets;
unsigned int i;
/* Buffers are already allocated, bail out. */
if (video->urb_size)
return 0;
- for (i = 0; i < UVC_URBS; ++i) {
- video->urb_buffer[i] = usb_buffer_alloc(video->dev->udev,
- size, GFP_KERNEL, &video->urb_dma[i]);
- if (video->urb_buffer[i] == NULL) {
- uvc_free_urb_buffers(video);
- return -ENOMEM;
+ /* 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) {
+ video->urb_buffer[i] = usb_buffer_alloc(
+ video->dev->udev, psize * npackets,
+ gfp_flags | __GFP_NOWARN, &video->urb_dma[i]);
+ if (!video->urb_buffer[i]) {
+ uvc_free_urb_buffers(video);
+ break;
+ }
+ }
+
+ if (i == UVC_URBS) {
+ video->urb_size = psize * npackets;
+ return npackets;
}
}
- video->urb_size = size;
return 0;
}
{
struct urb *urb;
unsigned int npackets, i, j;
- __u16 psize;
- __u32 size;
+ 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 = DIV_ROUND_UP(size, psize);
- if (npackets > UVC_MAX_ISO_PACKETS)
- npackets = UVC_MAX_ISO_PACKETS;
+ npackets = uvc_alloc_urb_buffers(video, size, psize, gfp_flags);
+ if (npackets == 0)
+ return -ENOMEM;
size = npackets * psize;
- if (uvc_alloc_urb_buffers(video, size) < 0)
- return -ENOMEM;
-
for (i = 0; i < UVC_URBS; ++i) {
urb = usb_alloc_urb(npackets, gfp_flags);
if (urb == NULL) {
struct usb_host_endpoint *ep, gfp_t gfp_flags)
{
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.
- */
+ unsigned int npackets, pipe, i;
+ u16 psize;
+ u32 size;
+
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;
- if (uvc_alloc_urb_buffers(video, size) < 0)
+ npackets = uvc_alloc_urb_buffers(video, size, psize, gfp_flags);
+ if (npackets == 0)
return -ENOMEM;
+ size = npackets * psize;
+
if (usb_endpoint_dir_in(&ep->desc))
pipe = usb_rcvbulkpipe(video->dev->udev,
ep->desc.bEndpointAddress);
*/
usb_set_interface(video->dev->udev, video->streaming->intfnum, 0);
- /* Some webcams don't suport GET_DEF requests on the probe control. We
- * fall back to GET_CUR if GET_DEF fails.
+ /* 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(video, probe, 1, GET_DEF) == 0)
+ uvc_set_video_ctrl(video, 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.
*/
- if ((ret = uvc_get_video_ctrl(video, probe, 1, GET_DEF)) < 0 &&
- (ret = uvc_get_video_ctrl(video, probe, 1, GET_CUR)) < 0)
+ if ((ret = uvc_get_video_ctrl(video, probe, 1, GET_CUR)) < 0)
return ret;
/* Check if the default format descriptor exists. Use the first
projects / linux-2.6-omap-h63xx.git / blobdiff