Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver

From: Sakari Ailus
Date: Wed Jun 07 2017 - 08:32:11 EST


On Sun, Jun 04, 2017 at 11:00:14AM -0700, Steve Longerbeam wrote:
>
>
> On 06/03/2017 11:02 AM, Steve Longerbeam wrote:
> >Hi Sakari,
> >
> >
> >On 05/29/2017 11:56 PM, Sakari Ailus wrote:
> >>Hi Steve,
> >>
> >>On Mon, May 29, 2017 at 02:50:34PM -0700, Steve Longerbeam wrote:
> >>>><snip>
> >>>>
> >>>>>+
> >>>>>+static int ov5640_s_ctrl(struct v4l2_ctrl *ctrl)
> >>>>>+{
> >>>>>+ struct v4l2_subdev *sd = ctrl_to_sd(ctrl);
> >>>>>+ struct ov5640_dev *sensor = to_ov5640_dev(sd);
> >>>>>+ int ret = 0;
> >>>>>+
> >>>>>+ mutex_lock(&sensor->lock);
> >>>>Could you use the same lock for the controls as you use for the
> >>>>rest? Just
> >>>>setting handler->lock after handler init does the trick.
> >>>
> >>>Can you please rephrase, I don't follow. "same lock for the controls as
> >>>you use for the rest" - there's only one device lock owned by this
> >>>driver
> >>>and I am already using that same lock.
> >>
> >>There's another in the control handler. You could use your own lock for
> >>the
> >>control handler as well.
> >
> >I still don't understand.
> >
>
> Hi Sakari, sorry I see what you are referring to now. The lock
> in 'struct v4l2_ctrl_handler' can be overridden by a caller's own
> lock. Yes that's a good idea, I'll do that.

Ack, good! :-)

--
Sakari Ailus
e-mail: sakari.ailus@xxxxxx XMPP: sailus@xxxxxxxxxxxxxx