The unxlate_dev_mem_ptr() function has no prototype on the sh architecture,
which does not include asm-generic/io.h. This results in the following
build failure.

drivers/char/mem.c: In function 'read_mem':
drivers/char/mem.c:164:25: error: implicit declaration of function 'unxlate_dev_mem_ptr'

This compile error is now seen because commit 99b619b37ae1 ("mips: provide
unxlate_dev_mem_ptr() in asm/io.h") removed the weak function which was
previously in place to handle the problem.

Add a trivial macro to the sh header to provide the now missing dummy
function.

Fixes: 99b619b37ae1 ("mips: provide unxlate_dev_mem_ptr() in asm/io.h")
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
 arch/sh/include/asm/io.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h
index fba90e670ed4..d8f3537ef57f 100644
--- a/arch/sh/include/asm/io.h
+++ b/arch/sh/include/asm/io.h
@@ -286,6 +286,7 @@ static inline void iounmap(volatile void __iomem *addr) { }
  * access
  */
 #define xlate_dev_mem_ptr(p)	__va(p)
+#define unxlate_dev_mem_ptr(p, v) do { } while (0)
 
 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
 int valid_phys_addr_range(phys_addr_t addr, size_t size);
-- 
2.39.2

On Tue, Jul 4, 2023, at 21:01, Guenter Roeck wrote:
> The unxlate_dev_mem_ptr() function has no prototype on the sh architecture,
> which does not include asm-generic/io.h. This results in the following
> build failure.
>
> drivers/char/mem.c: In function 'read_mem':
> drivers/char/mem.c:164:25: error: implicit declaration of function 
> 'unxlate_dev_mem_ptr'
>
> This compile error is now seen because commit 99b619b37ae1 ("mips: provide
> unxlate_dev_mem_ptr() in asm/io.h") removed the weak function which was
> previously in place to handle the problem.
>
> Add a trivial macro to the sh header to provide the now missing dummy
> function.
>
> Fixes: 99b619b37ae1 ("mips: provide unxlate_dev_mem_ptr() in asm/io.h")
> Cc: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Ideally, we should use the asm-generic/io.h header here, but as a hotfix
this should do.

Acked-by: Arnd Bergmann <arnd@arndb.de>

On Tue, 2023-07-04 at 12:01 -0700, Guenter Roeck wrote:
> The unxlate_dev_mem_ptr() function has no prototype on the sh architecture,
> which does not include asm-generic/io.h. This results in the following
> build failure.
> 
> drivers/char/mem.c: In function 'read_mem':
> drivers/char/mem.c:164:25: error: implicit declaration of function 'unxlate_dev_mem_ptr'
> 
> This compile error is now seen because commit 99b619b37ae1 ("mips: provide
> unxlate_dev_mem_ptr() in asm/io.h") removed the weak function which was
> previously in place to handle the problem.
> 
> Add a trivial macro to the sh header to provide the now missing dummy
> function.
> 
> Fixes: 99b619b37ae1 ("mips: provide unxlate_dev_mem_ptr() in asm/io.h")
> Cc: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
>  arch/sh/include/asm/io.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h
> index fba90e670ed4..d8f3537ef57f 100644
> --- a/arch/sh/include/asm/io.h
> +++ b/arch/sh/include/asm/io.h
> @@ -286,6 +286,7 @@ static inline void iounmap(volatile void __iomem *addr) { }
>   * access
>   */
>  #define xlate_dev_mem_ptr(p)	__va(p)
> +#define unxlate_dev_mem_ptr(p, v) do { } while (0)
>  
>  #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
>  int valid_phys_addr_range(phys_addr_t addr, size_t size);

Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>

I'm going to pick this up tomorrow before sending my PR to Linus.

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
  `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913

On Tue, 2023-07-04 at 12:01 -0700, Guenter Roeck wrote:
> The unxlate_dev_mem_ptr() function has no prototype on the sh architecture,
> which does not include asm-generic/io.h. This results in the following
> build failure.
> 
> drivers/char/mem.c: In function 'read_mem':
> drivers/char/mem.c:164:25: error: implicit declaration of function 'unxlate_dev_mem_ptr'
> 
> This compile error is now seen because commit 99b619b37ae1 ("mips: provide
> unxlate_dev_mem_ptr() in asm/io.h") removed the weak function which was
> previously in place to handle the problem.
> 
> Add a trivial macro to the sh header to provide the now missing dummy
> function.
> 
> Fixes: 99b619b37ae1 ("mips: provide unxlate_dev_mem_ptr() in asm/io.h")
> Cc: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
>  arch/sh/include/asm/io.h | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h
> index fba90e670ed4..d8f3537ef57f 100644
> --- a/arch/sh/include/asm/io.h
> +++ b/arch/sh/include/asm/io.h
> @@ -286,6 +286,7 @@ static inline void iounmap(volatile void __iomem *addr) { }
>   * access
>   */
>  #define xlate_dev_mem_ptr(p)	__va(p)
> +#define unxlate_dev_mem_ptr(p, v) do { } while (0)
>  
>  #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
>  int valid_phys_addr_range(phys_addr_t addr, size_t size);

Applied to my for-next tree for 6.5. PR will be sent tomorrow.

Thanks,
Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer
`. `'   Physicist
  `-    GPG: 62FF 8A75 84E0 2956 9546  0006 7426 3B37 F5B5 F913