Re: [RESEND PATCH v5 5/5] input: joystick: Add ADC attached joystick driver.

From: Andy Shevchenko
Date: Fri Apr 17 2020 - 17:50:19 EST


On Sat, Apr 18, 2020 at 12:24 AM Paul Cercueil <paul@xxxxxxxxxxxxxxx> wrote:
> Le sam. 18 avril 2020 Ã 0:10, Andy Shevchenko
> <andy.shevchenko@xxxxxxxxx> a Ãcrit :
> > On Fri, Apr 17, 2020 at 11:21 PM Artur Rojek <contact@xxxxxxxxxxxxxx>
> > wrote:

...

> >> +#include <linux/of.h>
> >
> > Do you really need this? (See below as well)

> >> +static const struct of_device_id adc_joystick_of_match[] = {
> >> + { .compatible = "adc-joystick", },
> >> + { },
> >> +};
> >> +MODULE_DEVICE_TABLE(of, adc_joystick_of_match);
> >> +
> >> +static struct platform_driver adc_joystick_driver = {
> >> + .driver = {
> >> + .name = "adc-joystick",
> >
> >> + .of_match_table =
> >> of_match_ptr(adc_joystick_of_match),
> >
> > Drop this a bit harmful of_match_ptr() macro. It should go with ugly
> > #ifdeffery. Here you simple introduced a compiler warning.
>
> I assume you mean #ifdef around the of_device_id + module table macro?

Yes.

> > On top of that, you are using device property API, OF use in this case
> > is contradictory (at lest to some extend).
>
> I don't see why. The fact that the driver can work when probed from
> platform code

Ha-ha, tell me how. I would like to be very surprised.

> doesn't mean that it shouldn't have a table to probe
> from devicetree.

I didn't get what you are talking about here. The idea of _unified_
device property API is to get rid of OF-centric code in favour of more
generic approach. Mixing those two can be done only in specific cases
(here is not the one).

--
With Best Regards,
Andy Shevchenko