[PATCH 5.10] drm/mediatek: Fix backport issue in mtk_drm_gem_prime_vmap()

[Greg Kroah-Hartman]

On Fri, Sep 22, 2023 at 08:51:17AM -0700, Nathan Chancellor wrote:
> When building with clang:
> 
>   drivers/gpu/drm/mediatek/mtk_drm_gem.c:255:10: error: incompatible integer to pointer conversion returning 'int' from a function with result type 'void *' [-Wint-conversion]
>     255 |                 return -ENOMEM;
>         |                        ^~~~~~~
>   1 error generated.
> 
> GCC reports the same issue as a warning, rather than an error.
> 
> Prior to commit 7e542ff8b463 ("drm/mediatek: Use struct dma_buf_map in
> GEM vmap ops"), this function returned a pointer rather than an integer.
> This function is indirectly called in drm_gem_vmap(), which treats NULL
> as -ENOMEM through an error pointer. Return NULL in this block to
> resolve the warning but keep the same end result.
> 
> Fixes: 43f561e809aa ("drm/mediatek: Fix potential memory leak if vmap() fail")
> Signed-off-by: Nathan Chancellor <nathan at kernel.org>
> ---
> This is a fix for a 5.10 backport, so it has no upstream relevance but
> I've still cc'd the relevant maintainers in case they have any comments
> or want to double check my work.

Now queued up, thanks.

greg k-h