Re: [PATCH] media: rockchip: rkisp1: remove some dead code

[Helen Koike]

Hi Dan,

Thank you for your patch.

On 11/30/20 9:53 AM, Dan Carpenter wrote:
> The debugfs_create_dir() function never returns NULLs.  It's not supposed
> to checked for errors in the normal case and there is no need to check
> in this function so let's just delete this dead code.
> 
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
>  drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c b/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c
> index 9af137e4967f..68da1eed753d 100644
> --- a/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c
> +++ b/drivers/media/platform/rockchip/rkisp1/rkisp1-dev.c
> @@ -430,10 +430,6 @@ static void rkisp1_debug_init(struct rkisp1_device *rkisp1)
>  	struct rkisp1_debug *debug = &rkisp1->debug;
>  
>  	debug->debugfs_dir = debugfs_create_dir(RKISP1_DRIVER_NAME, NULL);
> -	if (!debug->debugfs_dir) {
> -		dev_dbg(rkisp1->dev, "failed to create debugfs directory\n");
> -		return;
> -	}

I was taking a look at the debugfs_create_dir() code, and I saw it can
return ERR_PTR(), so ideally we should check for errors with IS_ERR() / PTR_ERR().

Also from the docs:

 * <snip>  If an error occurs, ERR_PTR(-ERROR) will be
 * returned.
 *
 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
 * returned.



>  	debugfs_create_ulong("data_loss", 0444, debug->debugfs_dir,
>  			     &debug->data_loss);
>  	debugfs_create_ulong("outform_size_err", 0444,  debug->debugfs_dir,
> 


nit: I would change the name of the commit just to make it clear what it
does.
Example: Remove useless error check from debugfs_create_dir()

Thanks,
Helen