Re: [PATCH] drivers: Let several drivers depends on HAS_IOMEM for 'devm_ioremap_resource'

From: Thierry Reding
Date: Thu Jul 17 2014 - 04:43:37 EST


On Thu, Jul 17, 2014 at 09:27:58AM +0800, Chen Gang wrote:
[...]
> diff --git a/include/linux/device.h b/include/linux/device.h
> index c2421e0..a7500c3 100644
> --- a/include/linux/device.h
> +++ b/include/linux/device.h
> @@ -630,7 +630,16 @@ extern unsigned long devm_get_free_pages(struct device *dev,
> gfp_t gfp_mask, unsigned int order);
> extern void devm_free_pages(struct device *dev, unsigned long addr);
>
> +#ifdef CONFIG_HAS_IOMEM
> void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res);
> +#elif defined(CONFIG_COMPILE_TEST)
> +static inline void __iomem *devm_ioremap_resource(struct device *dev,
> + struct resource *res)
> +{
> + pr_warn("no hardware io memory, only for COMPILE_TEST\n");

Maybe: "Hardware doesn't support memory-mapped I/O"? I'm not sure if
it's useful to include the reference to COMPILE_TEST, especially since
the #elif will be dropped in favour of a simple #else.

> + return (__force void __iomem *)ERR_PTR(-ENXIO);

There's apparently an IOMEM_ERR_PTR() for this nowadays...

> +}
> +#endif /* CONFIG_HAS_IOMEM || CONFIG_COMPILE_TEST */
>
> /* allows to add/remove a custom action to devres stack */
> int devm_add_action(struct device *dev, void (*action)(void *), void *data);
> diff --git a/include/linux/io.h b/include/linux/io.h
> index b76e6e5..59128aa 100644
> --- a/include/linux/io.h
> +++ b/include/linux/io.h
> @@ -58,14 +58,42 @@ static inline void devm_ioport_unmap(struct device *dev, void __iomem *addr)
> }
> #endif
>
> +#ifdef CONFIG_HAS_IOMEM
> +
> void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
> unsigned long size);
> void __iomem *devm_ioremap_nocache(struct device *dev, resource_size_t offset,
> unsigned long size);
> void devm_iounmap(struct device *dev, void __iomem *addr);
> +void devm_ioremap_release(struct device *dev, void *res);
> +
> +#elif defined(CONFIG_COMPILE_TEST)
> +
> +static inline void __iomem *devm_ioremap(struct device *dev,
> + resource_size_t offset, unsigned long size)

For consistency with other functions above, please keep arguments on
subsequent lines aligned with the first argument on the first line, like
so:

static inline void __iomem *devm_ioremap(struct device *dev,
resource_size_t offset,
unsigned long size)

> +{
> + pr_warn("no hardware io memory, only for COMPILE_TEST\n");
> + return NULL;
> +}
> +static inline void __iomem *devm_ioremap_nocache(struct device *dev,
> + resource_size_t offset, unsigned long size)
> +{
> + pr_warn("no hardware io memory, only for COMPILE_TEST\n");
> + return NULL;
> +}

Perhaps this should call devm_ioremap() so we don't have to repeat the
same error message? Or maybe make it:

#define devm_ioremap_nocache devm_ioremap

?

Thierry

Attachment: pgpKv_ywsSDXH.pgp
Description: PGP signature