Re: [PATCH RFC v2] media: i2c: mt9p031: add OF support

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Prabhakar,

On Thursday 02 May 2013 18:48:37 Prabhakar Lad wrote:
> On Thu, May 2, 2013 at 4:32 PM, Laurent Pinchart wrote:
> > On Thursday 02 May 2013 12:34:25 Prabhakar Lad wrote:
> >> On Thu, May 2, 2013 at 12:25 PM, Sascha Hauer wrote:
> >> > On Thu, May 02, 2013 at 11:52:34AM +0530, Prabhakar Lad wrote:
> >> >> From: Lad, Prabhakar <prabhakar.csengg@gmail.com>
> >> >> 
> >> >> add OF support for the mt9p031 sensor driver.
> >> >> Alongside this patch sorts the header inclusion alphabetically.

[snip]

> >> >> @@ -1070,8 +1120,16 @@ static const struct i2c_device_id mt9p031_id[]
> >> >> = {
> >> >>  };
> >> >>  MODULE_DEVICE_TABLE(i2c, mt9p031_id);
> >> >> 
> >> >> +static const struct of_device_id mt9p031_of_match[] = {
> >> >> +     { .compatible = "aptina,mt9p031", },
> >> >> +     { .compatible = "aptina,mt9p031m", },
> >> >> +     {},
> >> >> +};
> >> > 
> >> > I would have expected something like:
> >> > 
> >> > static const struct of_device_id mt9p031_of_match[] = {
> >> >         {
> >> >                 .compatible = "aptina,mt9p031-sensor",
> >> >                 .data = (void *)MT9P031_MODEL_COLOR,
> >> >         }, {
> >> >                 .compatible = "aptina,mt9p031m-sensor",
> >> >                 .data = (void *)MT9P031_MODEL_MONOCHROME,
> >> >         }, {
> >> >                 /* sentinel */
> >> >         },
> >> > };
> >> > 
> >> >         of_id = of_match_device(mt9p031_of_match, &client->dev);
> >> >         if (of_id)
> >> >                 mt9p031->model = (enum mt9p031_model)of_id->data;
> >> > 
> >> > To handle monochrome sensors.
> >> 
> >> OK will do the same.
> > 
> > And please guard the table with #ifdef CONFIG_OF.
> 
> But guarding the table #ifdef CONFIG_OF would cause compilation failure
> for below code when CONFIG_OF is undefined in probe
> 
> of_id = of_match_device(of_match_ptr(mt9p031_of_match),
> 			&client->dev);
> if (of_id)
> 	mt9p031->model = (enum mt9p031_model)of_id->data;

You could guard the above code with an #ifdef CONFIG_OF as well.

> and also in mt9p031_i2c_driver structure,
> of_match_table = of_match_ptr(mt9p031_of_match),
> 
> which force me to define mt9p031_of_match to NULL when
> CONFIG_OF is undefined

of_match_ptr is defined as NULL when CONFIG_OF is disabled.

-- 
Regards,

Laurent Pinchart