lkml.org 
[lkml]   [2022]   [Feb]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3 1/2] media: uvcvideo: Only create input devs if hw supports it
Hi Ricardo,

Thank you for the patch.

On Mon, Jan 24, 2022 at 08:00:12PM +0100, Ricardo Ribalda wrote:
> Examine the stream headers to figure out if the device has a GPIO and
> can be used as an input.
>
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>
> ---
> drivers/media/usb/uvc/uvc_status.c | 23 +++++++++++++++++++++++
> 1 file changed, 23 insertions(+)
>
> diff --git a/drivers/media/usb/uvc/uvc_status.c b/drivers/media/usb/uvc/uvc_status.c
> index 753c8226db70..3ef0b281ffc5 100644
> --- a/drivers/media/usb/uvc/uvc_status.c
> +++ b/drivers/media/usb/uvc/uvc_status.c
> @@ -18,11 +18,34 @@
> * Input device
> */
> #ifdef CONFIG_USB_VIDEO_CLASS_INPUT_EVDEV
> +
> +static bool uvc_input_has_button(struct uvc_device *dev)
> +{
> + struct uvc_streaming *stream;
> +
> + /*
> + * The device has GPIO button event if both bTriggerSupport and

The UVC specification doesn't talk about GPIOs but about buttons. With
s/GPIO button event/button events/ here and s/GPIO/button/ in the commit
message,

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

> + * bTriggerUsage are one. Otherwise the camera button does not
> + * exist or is handled automatically by the camera without host
> + * driver or client application intervention.
> + */
> + list_for_each_entry(stream, &dev->streams, list) {
> + if (stream->header.bTriggerSupport == 1 &&
> + stream->header.bTriggerUsage == 1)
> + return true;
> + }
> +
> + return false;
> +}
> +
> static int uvc_input_init(struct uvc_device *dev)
> {
> struct input_dev *input;
> int ret;
>
> + if (!uvc_input_has_button(dev))
> + return 0;
> +
> input = input_allocate_device();
> if (input == NULL)
> return -ENOMEM;

--
Regards,

Laurent Pinchart

\
 
 \ /
  Last update: 2022-02-03 04:19    [W:0.185 / U:0.484 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site