Re: [PATCH] of: Turn of_match_node into a static inline when CONFIG_OF isn't set

From: Laurent Pinchart
Date: Tue Feb 11 2014 - 09:54:39 EST


Hi Josh,

On Tuesday 11 February 2014 08:41:08 Josh Cartwright wrote:
> On Tue, Feb 11, 2014 at 01:36:51PM +0100, Laurent Pinchart wrote:
> > when CONFIG_OF is disabled of_match_node is defined as a macro that
> > evaluates to NULL. This breaks compilation of drivers that dereference
> > the function's return value directly. Fix it by turning the macro into a
> > static inline function that returns NULL.
>
> Just this past week I did the same thing, but noticed that it breaks the
> following usecase:
>
> #ifdef CONFIG_OF
> static const struct of_device_id foobar_matches[] = {
> { .compatible = "foobar,whatsit", },
> { },
> };
> #endif
>
> static int probeme(struct platform_device *pdev)
> {
> struct of_device_id *id;
>
> id = of_match_node(foobar_matches, pdev->dev.of_node);
> if (id) {
> /* ... */
> }
> return 0;
> }
>
> When !CONFIG_OF and with your change, this will fail to build due to
> foobar_matches being undefined.

Good point. What would you think about

#define of_match_node(_matches, _node) ((const struct of_device_id *)NULL)

?

--
Regards,

Laurent Pinchart

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