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Subject: Re: [PATCH v7 16/34] [media] add Omnivision OV5640 sensor driver
From: Steve Longerbeam <slongerbeam@gmail.com>
To: Sakari Ailus <sakari.ailus@iki.fi>
Cc: robh+dt@kernel.org, mark.rutland@arm.com, shawnguo@kernel.org,
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Date: Sun, 4 Jun 2017 11:00:14 -0700
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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.

Steve