Hi Ricardo,
Thank you for the patch.
On Friday 21 August 2015 15:19:25 Ricardo Ribalda Delgado wrote:
> This driver does not use the control infrastructure.
> Add support for the new field which on structure
> v4l2_ext_controls
>
> Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@xxxxxxxxx>
> ---
> drivers/media/usb/uvc/uvc_v4l2.c | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c
> b/drivers/media/usb/uvc/uvc_v4l2.c index 2764f43607c1..e6d3a1bcfa2f 100644
> --- a/drivers/media/usb/uvc/uvc_v4l2.c
> +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> @@ -980,6 +980,7 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file, void
> *fh, struct uvc_fh *handle = fh;
> struct uvc_video_chain *chain = handle->chain;
> struct v4l2_ext_control *ctrl = ctrls->controls;
> + struct v4l2_queryctrl qc;
> unsigned int i;
> int ret;
>
> @@ -988,7 +989,14 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file,
> void *fh, return ret;
>
> for (i = 0; i < ctrls->count; ++ctrl, ++i) {
> - ret = uvc_ctrl_get(chain, ctrl);
> + if (ctrls->which == V4L2_CTRL_WHICH_DEF_VAL) {
> + qc.id = ctrl->id;
> + ret = uvc_query_v4l2_ctrl(chain, &qc);
The uvc_ctrl_begin() call above locks chain->ctrl_mutex, and
uvc_query_v4l2_ctrl() will then try to acquire the same lock. That's not a
good idea :-)
I propose moving the ctrls->which check before the uvc_ctrl_begin() call and
implement it as
if (ctrls->which == V4L2_CTRL_WHICH_DEF_VAL) {
for (i = 0; i < ctrls->count; ++ctrl, ++i) {
struct v4l2_queryctrl qc = { .id = ctrl->id };
ret = uvc_query_v4l2_ctrl(chain, &qc);
if (ret < 0) {
ctrls->error_idx = i;
return ret;
}
ctrl->value = qc.default_value;
}
return 0;
}
> + if (!ret)
> + ctrl->value = qc.default_value;
> + } else
> + ret = uvc_ctrl_get(chain, ctrl);
> +
> if (ret < 0) {
> uvc_ctrl_rollback(handle);
> ctrls->error_idx = i;
> @@ -1010,6 +1018,10 @@ static int uvc_ioctl_s_try_ext_ctrls(struct uvc_fh
> *handle, unsigned int i;
> int ret;
>
> + /* Default value cannot be changed */
> + if (ctrls->which == V4L2_CTRL_WHICH_DEF_VAL)
> + return -EINVAL;
> +
> ret = uvc_ctrl_begin(chain);
> if (ret < 0)
> return ret;
--
Regards,
Laurent Pinchart
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