Re: [PATCH v2] [media] staging/imx: remove confusing IS_ERR_OR_NULL usage

From: Philipp Zabel
Date: Wed Jul 12 2017 - 11:50:24 EST

On Tue, 2017-07-11 at 15:18 +0200, Arnd Bergmann wrote:
> While looking at a compiler warning, I noticed the use of
> IS_ERR_OR_NULL, which is generally a sign of a bad API design
> and should be avoided.
> In this driver, this is fairly easy, we can simply stop storing
> error pointers in persistent structures, and change the two
> functions that might return either a NULL pointer or an error
> code to consistently return error pointers when failing.
> of_parse_subdev() now separates the error code and the pointer
> it looks up, to clarify the interface. There are two cases
> where this function originally returns 'NULL', and I have
> changed that to '0' for success to keep the current behavior,
> though returning an error would also make sense there.
> Fixes: e130291212df ("[media] media: Add i.MX media core driver")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
> v2: fix type mismatch
> v3: rework of_parse_subdev() as well.


Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
Tested-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>