Re: [PATCH 10/10] uvcvideo: Send control change events for slave ctrls when the master changes

Laurent Pinchart
2012-03-28T09:34:22Z

Hi Hans,

Thanks for the patch.

On Sunday 25 March 2012 13:56:50 Hans de Goede wrote:
> This allows v4l2 control UI-s to update the inactive state (ie grey-ing
> out of controls) for slave controls when the master control changes.
>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> drivers/media/video/uvc/uvc_ctrl.c | 55 +++++++++++++++++++++++++++++++--
> 1 file changed, 52 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/media/video/uvc/uvc_ctrl.c
> b/drivers/media/video/uvc/uvc_ctrl.c index 91d9007..2d06fd8 100644
> --- a/drivers/media/video/uvc/uvc_ctrl.c
> +++ b/drivers/media/video/uvc/uvc_ctrl.c

[snip]

> +static void uvc_ctrl_send_events(struct uvc_fh *handle,
> + struct v4l2_ext_control *xctrls, int xctrls_count)
> +{
> + struct uvc_control_mapping *mapping;
> + struct uvc_control *ctrl;
> + u32 changes = V4L2_EVENT_CTRL_CH_VALUE;
> + int i, j;
> +
> for (i = 0; i < xctrls_count; ++i) {
> ctrl = uvc_find_control(handle->chain, xctrls[i].id, &mapping);
> +
> + for (j = 0; j < ARRAY_SIZE(mapping->slave_ids); ++j) {
> + if (!mapping->slave_ids[j])
> + break;
> + uvc_ctrl_send_slave_event(handle,
> + mapping->slave_ids[j],
> + xctrls, xctrls_count);
> + }
> +
> + /*
> + * If the master is being modified in the same transaction
> + * flags may change too.
> + */
> + if (mapping->master_id)
> + for (j = 0; j < xctrls_count; j++)
> + if (xctrls[j].id == mapping->master_id) {
> + changes |= V4L2_EVENT_CTRL_CH_FLAGS;

Should you verify that the modification to the master control actually caused
a slave control flags change, or would that be overkill ?

> + break;
> + }

Could you please put brackets around the for and the if ?

> +
> uvc_ctrl_send_event(handle, ctrl, mapping, xctrls[i].value,
> - V4L2_EVENT_CTRL_CH_VALUE);
> + changes);
> }
> }

--
Regards,

Laurent Pinchart