Re: [PATCH v2 2/3] usb: gadget/uvc: also handle v4l2 ioctl ENUM_FMT

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Michael,

On Monday 25 August 2014 15:59:57 Michael Grzeschik wrote:
> On Wed, Aug 20, 2014 at 07:05:30PM +0200, Laurent Pinchart wrote:
> > On Wednesday 20 August 2014 02:06:54 Hans Verkuil wrote:
> > > On 08/19/2014 05:01 PM, Laurent Pinchart wrote:
> > > > Hi Michael,
> > > > 
> > > > Thank you for the patch.
> > > > 
> > > > (CC'ing Hans Verkuil and the linux-media mailing list)
> > > > 
> > > > On Friday 08 August 2014 17:38:58 Michael Grzeschik wrote:
> > > >> This patch adds ENUM_FMT as possible ioctl to the uvc v4l2 device.
> > > >> That makes userspace applications with a generic IOCTL calling
> > > >> convention make also use of it.
> > > >> 
> > > >> Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
> > > >> ---
> > > >> 
> > > >> v1 -> v2:
> > > >>  - changed first switch case to simple if
> > > >>  - added separate function
> > > >>  - added description field
> > > >>  - bail out on array boundaries
> > > >>  
> > > >>  drivers/usb/gadget/uvc_v4l2.c | 30 ++++++++++++++++++++++++++++--
> > > >>  1 file changed, 28 insertions(+), 2 deletions(-)
> > > >> 
> > > >> diff --git a/drivers/usb/gadget/uvc_v4l2.c
> > > >> b/drivers/usb/gadget/uvc_v4l2.c
> > > >> index ad48e81..58633bf 100644
> > > >> --- a/drivers/usb/gadget/uvc_v4l2.c
> > > >> +++ b/drivers/usb/gadget/uvc_v4l2.c
> > > >> @@ -55,14 +55,30 @@ struct uvc_format
> > > >>  {
> > > >>  	u8 bpp;
> > > >>  	u32 fcc;
> > > >> +	char *description;
> > > >>  };
> > > >>  
> > > >>  static struct uvc_format uvc_formats[] = {
> > > >> -	{ 16, V4L2_PIX_FMT_YUYV  },
> > > >> -	{ 0,  V4L2_PIX_FMT_MJPEG },
> > > >> +	{ 16, V4L2_PIX_FMT_YUYV, "YUV 4:2:2" },
> > > >> +	{ 0,  V4L2_PIX_FMT_MJPEG, "MJPEG" },
> > > > 
> > > > Format descriptions are currently duplicated in every driver, causing
> > > > higher memory usage and different descriptions for the same format
> > > > depending on the driver. Hans, should we try to fix this ?
> > > 
> > > Yes, we should. It's been on my todo list for ages, but at a very low
> > > priority. I'm not planning to work on this in the near future, but if
> > > someone else wants to work on this, then just go ahead.
> > 
> > Michael, would you like to give this a try, or should I do it ?
> 
> It seems Philipp is already taking the chance! :)

Perfect timing, I wonder if that's just a coincidence ;-)

I don't think this patch is very urgent, would you be fine with rebasing it on 
top of Philipp's patch when it will be accepted ?

-- 
Regards,

Laurent Pinchart