Re: [PATCH RFC v5] s5k5baf: add camera sensor driver

[Stephen Warren <swarren@wwwdotorg.org>]

On 08/19/2013 04:53 PM, Tomasz Figa wrote:
> On Monday 19 of August 2013 16:30:45 Stephen Warren wrote:
>> On 08/19/2013 11:25 AM, Sylwester Nawrocki wrote:
>>> On 08/19/2013 03:25 PM, Pawel Moll wrote:
>>>> On Mon, 2013-08-19 at 14:18 +0100, Andrzej Hajda wrote:
>>>>> +++ b/Documentation/devicetree/bindings/media/samsung-s5k5baf.txt
>>>>> @@ -0,0 +1,51 @@
>>>>> +Samsung S5K5BAF UXGA 1/5" 2M CMOS Image Sensor with embedded SoC
>>>>> ISP
>>>>> +-------------------------------------------------------------
>>>>> +
>>>>> +Required properties:
>>>>> +
>>>>> +- compatible     : "samsung,s5k5baf";
>>>>> +- reg            : I2C slave address of the sensor;
>>>>> +- vdda-supply    : analog power supply 2.8V (2.6V to 3.0V);
>>>>> +- vddreg-supply          : regulator input power supply 1.8V (1.7V
>>>>> to 1.9V) +                    or 2.8V (2.6V to 3.0);
>>>>> +- vddio-supply   : I/O power supply 1.8V (1.65V to 1.95V)
>>>>> +                    or 2.8V (2.5V to 3.1V);
>>>>> +- gpios                  : GPIOs connected to STDBYN and RSTN pins,
>>>>> +                    in order: STBYN, RSTN;
>>>>
>>>> You probably want to use the "[<name>-]gpios" convention here (see
>>>> Documentation/devicetree/bindings/gpio/gpio.txt), so something like
>>>> stbyn-gpios and rstn-gpios.
>>>
>>> Unless using multiple named properties is really preferred over a
>>> single "gpios" property I would like to keep the single property
>>> containing a list of GPIOs. ...
>>
>> Yes, a separate property for each type of GPIO is typical. Multiple
>> entries in the same property are allowed if they're used for the same
>> purpose/type, whereas here they're clearly different things.
>> Inconsistent with (some) other properties, admittedly...
> 
> I'm not really convinced about the superiority of named gpio properties 
> over a single gpios property with multiple entries in this case. I'd say 
> it's more just a matter of preference.
> 
> See the clock or interrupt bindings. They all specify all the clocks and 
> interrupts in single property, without any differentiation based on their 
> purposes. Also keep in mind that original GPIO bindings used only a single 
> "gpios" property and was only extended to allow named ones.

Well, it's not so much about what's best, but just being consistent with
what's already there.