Subject: [PATCH] media: i2c: adv7343: fix the DT binding properties

From: [email-masked] (Sylwester Nawrocki)
Date: Fri, 20 Sep 2013 11:52:32 +0200

Hi Prabhakar,

On 09/20/2013 10:11 AM, Prabhakar Lad wrote:
> OK I will, just send out a fix up patch which fixes the mismatch between
> names for the rc-cycle, and later send out a patch which removes the
> platform data usage for next release with proper DT bindings.

I think the binding need to be fully corrected now, I just meant to not
touch the board file, i.e. leave non-dt support unchanged.

> I'm OK with making regulator properties as optional, But still it would
> change the meaning of what DT is, we know that the VDD/VDD_IO .. etc
> pins are required properties (but still making them as optional) :-(
> 
> I think there might several devices where this situation may arise so
> just thinking of a alternative solution.
> 
> say we have property 'software-regulator' which takes true/false(0/1)
> If set to true we make the regulators as required property or else we
> assume it is handled and ignore it ?

I don't think this is a good idea. You would have to add a similar platform 
data flag for non-dt, it doesn't sound right. I can see two options here: 

1. Make the regulator properties mandatory and, e.g. define a fixed 
   voltage GPIO regulator in DT with an empty 'gpio' property. Then
   pass a phandle to that regulator in the adv7343 *-supply properties.
   For non-dt similarly a fixed voltage regulator(s) and voltage 
   supplies  would need to be defined in the board files.

2. Make the properties optional and use (devm_)regulator_get_optional()
   calls in the driver (a recently added function). I must admit I don't 
   fully understand description of this function, it currently looks 
   pretty much same as (devm_)regulator_get(). Thus the driver would 
   need to be handling regulator supplies only when non ERR_PTR() is 
   returned from regulator_get_optional() and otherwise assume a non 
   critical error. There is already quite a few example occurrences of 
   regulator_get_optional() usage.

--
Regards,
Sylwester