V4L/DVB (11247): hdpvr: empty internal device buffer after stopping streaming

Makes the next capturing starting faster and more reliable.

Signed-off-by: Janne Grunau <j@jannau.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Janne Grunau 2009-03-27 20:21:17 -03:00 committed by Mauro Carvalho Chehab
parent 9ef77adfb9
commit 7d771ff0dc

View File

@ -298,11 +298,20 @@ static int hdpvr_start_streaming(struct hdpvr_device *dev)
/* function expects dev->io_mutex to be hold by caller */
static int hdpvr_stop_streaming(struct hdpvr_device *dev)
{
uint actual_length, c = 0;
u8 *buf;
if (dev->status == STATUS_IDLE)
return 0;
else if (dev->status != STATUS_STREAMING)
return -EAGAIN;
buf = kmalloc(dev->bulk_in_size, GFP_KERNEL);
if (!buf)
v4l2_err(&dev->v4l2_dev, "failed to allocate temporary buffer "
"for emptying the internal device buffer. "
"Next capture start will be slow\n");
dev->status = STATUS_SHUTTING_DOWN;
hdpvr_config_call(dev, CTRL_STOP_STREAMING_VALUE, 0x00);
mutex_unlock(&dev->io_mutex);
@ -316,6 +325,23 @@ static int hdpvr_stop_streaming(struct hdpvr_device *dev)
/* kill the still outstanding urbs */
hdpvr_cancel_queue(dev);
/* emptying the device buffer beforeshutting it down */
while (buf && ++c < 500 &&
!usb_bulk_msg(dev->udev,
usb_rcvbulkpipe(dev->udev,
dev->bulk_in_endpointAddr),
buf, dev->bulk_in_size, &actual_length,
BULK_URB_TIMEOUT)) {
/* wait */
msleep(5);
v4l2_dbg(MSG_BUFFER, hdpvr_debug, &dev->v4l2_dev,
"%2d: got %d bytes\n", c, actual_length);
}
kfree(buf);
v4l2_dbg(MSG_BUFFER, hdpvr_debug, &dev->v4l2_dev,
"used %d urbs to empty device buffers\n", c-1);
msleep(10);
dev->status = STATUS_IDLE;
return 0;