Re: [PATCH v7] s5k5baf: add camera sensor driver

[Sylwester Nawrocki <s.nawrocki@samsung.com>]

On 08/23/2013 11:23 AM, Sylwester Nawrocki wrote:
>>>> +- stbyn-gpios	  : GPIO connected to STDBYN pin;
>>>> >> > +- rstn-gpios	  : GPIO connected to RSTN pin;
>> >
>> > Both GPIOs above have names suggesting that they are active low. I wonder 
>> > how the GPIO flags cell is interpreted here, namely the polarity bit.

To be more clear, the polarity bit specifies GPIO state at the GPIO controller
(SoC) that corresponds to active STANDBY or RESET signal state at the sensor.
So it is supposed to cover any inverter in between the sensor and an SoC.

> That's a good point. The GPIO flags are be used to specify active state
> of the GPIO. Some sensors happen to use different active state for those
> signals. It's not the case for this sensor though AFAICT.
> 
> Anyway IMO it would be better to name those gpios: "stby-gpios",
> "rst-gpios" in case there appear revisions that have their pin named STDBY
> or RST rather than STDBYN, RSTN. That seems rather unlikely though, but
> since there are devices to which that could apply I think for consistency
> it might be better to remove indication of polarity from the GPIO names.



-- 
Sylwester Nawrocki
Samsung R&D Institute Poland