[PATCH] nvmem: meson-efuse: Fix return value of nvmem callbacks

[neil.armstrong at linaro.org]

On 11/06/2024 16:55, Joy Chakraborty wrote:
> Read/write callbacks registered with nvmem core expect 0 to be returned
> on success and a negative value to be returned on failure.
> 
> meson_efuse_read() and meson_efuse_write() call into
> meson_sm_call_read() and meson_sm_call_write() respectively which return
> the number of bytes read or written on success as per their api
> description.
> 
> Fix to return error if meson_sm_call_read()/meson_sm_call_write()
> returns an error else return 0.
> 
> Fixes: a29a63bdaf6f ("nvmem: meson-efuse: simplify read callback")
> Cc: stable at vger.kernel.org
> Signed-off-by: Joy Chakraborty <joychakr at google.com>
> ---
>   drivers/nvmem/meson-efuse.c | 14 ++++++++++----
>   1 file changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/nvmem/meson-efuse.c b/drivers/nvmem/meson-efuse.c
> index 52ed9a62ca5b..d7f9ac99a212 100644
> --- a/drivers/nvmem/meson-efuse.c
> +++ b/drivers/nvmem/meson-efuse.c
> @@ -18,18 +18,24 @@ static int meson_efuse_read(void *context, unsigned int offset,
>   			    void *val, size_t bytes)
>   {
>   	struct meson_sm_firmware *fw = context;
> +	int ret;
>   
> -	return meson_sm_call_read(fw, (u8 *)val, bytes, SM_EFUSE_READ, offset,
> -				  bytes, 0, 0, 0);
> +	ret = meson_sm_call_read(fw, (u8 *)val, bytes, SM_EFUSE_READ, offset,
> +				 bytes, 0, 0, 0);
> +
> +	return ret < 0 ? ret : 0;
>   }
>   
>   static int meson_efuse_write(void *context, unsigned int offset,
>   			     void *val, size_t bytes)
>   {
>   	struct meson_sm_firmware *fw = context;
> +	int ret;
> +
> +	ret = meson_sm_call_write(fw, (u8 *)val, bytes, SM_EFUSE_WRITE, offset,
> +				  bytes, 0, 0, 0);
>   
> -	return meson_sm_call_write(fw, (u8 *)val, bytes, SM_EFUSE_WRITE, offset,
> -				   bytes, 0, 0, 0);
> +	return ret < 0 ? ret : 0;
>   }
>   
>   static const struct of_device_id meson_efuse_match[] = {

Reviewed-by: Neil Armstrong <neil.armstrong at linaro.org>