Re: [RFC/PATCH 1/5] v4l: Convert V4L2_CID_FOCUS_AUTO control to a menu control

[Sylwester Nawrocki <snjw23@gmail.com>]

On 12/10/2011 11:33 AM, Sakari Ailus wrote:
> On Sun, Dec 04, 2011 at 04:16:12PM +0100, Sylwester Nawrocki wrote:
>> Change the V4L2_CID_FOCUS_AUTO control type from boolean to a menu
>> type. In case of boolean control we had values 0 and 1 corresponding
>> to manual and automatic focus respectively.
>>
>> The V4L2_CID_FOCUS_AUTO menu control has currently following items:
>>   0 - V4L2_FOCUS_MANUAL,
>>   1 - V4L2_FOCUS_AUTO,
>>   2 - V4L2_FOCUS_AUTO_MACRO,
>>   3 - V4L2_FOCUS_AUTO_CONTINUOUS.
> 
> I would put the macro mode to a separate menu since it's configuration for
> how the regular AF works rather than really different mode.
> 
> ...
> 
>> @@ -567,6 +576,7 @@ const char *v4l2_ctrl_get_name(u32 id)
>>  	case V4L2_CID_PRIVACY:			return "Privacy";
>>  	case V4L2_CID_IRIS_ABSOLUTE:		return "Iris, Absolute";
>>  	case V4L2_CID_IRIS_RELATIVE:		return "Iris, Relative";
>> +	case V4L2_CID_DO_AUTO_FOCUS:		return "Do Auto Focus";
> 
> I'd perhaps use "begin" or "start". How does the user learn the autofocus
> has finished? I think this looks like quite similar problem than telling the
> flash strobe status to the user. The solution could also be similar to that.

Hi,

considering your previous comments, how about the below focusing control set ?

Controls for starting/stopping auto focusing (for V4L2_CID_FOCUS_AUTO ==
V4L2_FOCUS_MANUAL):

V4L2_CID_START_AUTO_FOCUS  - (button) - start auto focusing,
V4L2_CID_STOP_AUTO_FOCUS   - (button) - stop auto focusing (might be also
                                        useful in V4L2_FOCUS_AUTO_CONTINUOUS
                                        mode)
and auto focus status:

V4L2_CID_AUTO_FOCUS_STATUS - (boolean) - whether focusing is in progress or not
                             (when V4L2_CID_FOCUS_AUTO == V4L2_FOCUS_MANUAL)


V4L2_CID_FOCUS_AUTO would basically retain it's current semantics:

V4L2_CID_FOCUS_AUTO        - (boolean) - select focus type (manual/auto
                                         continuous)
        V4L2_FOCUS_MANUAL              - manual focus
        V4L2_FOCUS_AUTO_CONTINUOUS     - continuous auto focus
                                         (or V4L2_FOCUS_AUTO)

New menu control to choose behaviour of auto focus (either single-shot
or continuous):

V4L2_CID_AF_MODE                        - select auto focus mode
        V4L2_AF_MODE_NORMAL             - "normal" auto focus
        V4L2_AF_MODE_MACRO              - macro (close-up)
        V4L2_AF_MODE_SPOT               - spot location passed with
                                          selection API or other control
        V4L2_AF_MODE_FACE_DETECTION	- focus point indicated by internal
                                          face detector


I might try it out and implement in M-5MOLS driver, to see how it works
in practice.

Does it make sense for you ?

--

Regards,
Sylwester