Hi Arnd,
thank you for the cleanup. I see two issues below:
On Wed, 2017-06-28 at 22:13 +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 one
> function that might return either a NULL pointer or an error
> code to consistently return error pointers when failing.
>
> Fixes: e130291212df ("[media] media: Add i.MX media core driver")
> Signed-off-by: Arnd Bergmann <a...@arndb.de>
> ---
> I can't reproduce the original warning any more, but this
> patch still makes sense by itself.
> ---
> drivers/staging/media/imx/imx-ic-prpencvf.c | 41
> ++++++++++++++++-------------
> drivers/staging/media/imx/imx-media-csi.c | 29 +++++++++++---------
> drivers/staging/media/imx/imx-media-dev.c | 2 +-
> drivers/staging/media/imx/imx-media-of.c | 2 +-
> drivers/staging/media/imx/imx-media-vdic.c | 37 ++++++++++++++------------
> 5 files changed, 61 insertions(+), 50 deletions(-)
>
[...]
> diff --git a/drivers/staging/media/imx/imx-media-csi.c
> b/drivers/staging/media/imx/imx-media-csi.c
> index a2d26693912e..a4b3c305dcc8 100644
> --- a/drivers/staging/media/imx/imx-media-csi.c
> +++ b/drivers/staging/media/imx/imx-media-csi.c
> @@ -122,11 +122,11 @@ static inline struct csi_priv *sd_to_dev(struct
> v4l2_subdev *sdev)
>
> static void csi_idmac_put_ipu_resources(struct csi_priv *priv)
> {
> - if (!IS_ERR_OR_NULL(priv->idmac_ch))
> + if (priv->idmac_ch)
> ipu_idmac_put(priv->idmac_ch);
> priv->idmac_ch = NULL;
>
> - if (!IS_ERR_OR_NULL(priv->smfc))
> + if (priv->smfc)
> ipu_smfc_put(priv->smfc);
> priv->smfc = NULL;
> }
> @@ -134,23 +134,26 @@ static void csi_idmac_put_ipu_resources(struct csi_priv
> *priv)
> static int csi_idmac_get_ipu_resources(struct csi_priv *priv)
> {
> int ch_num, ret;
> + struct ipu_smfc *smfc, *idmac_ch;
This should be
+ struct ipuv3_channel *idmac_ch;
+ struct ipu_smfc *smfc;
instead.
[...]
> diff --git a/drivers/staging/media/imx/imx-media-dev.c
> b/drivers/staging/media/imx/imx-media-dev.c
> index 48cbc7716758..c58ff0831890 100644
> --- a/drivers/staging/media/imx/imx-media-dev.c
> +++ b/drivers/staging/media/imx/imx-media-dev.c
> @@ -91,7 +91,7 @@ imx_media_add_async_subdev(struct imx_media_dev *imxmd,
> if (imx_media_find_async_subdev(imxmd, np, devname)) {
> dev_dbg(imxmd->md.dev, "%s: already added %s\n",
> __func__, np ? np->name : devname);
> - imxsd = NULL;
> + imxsd = ERR_PTR(-EEXIST);
And since this returns -EEXIST now, ...
> goto out;
> }
>
> diff --git a/drivers/staging/media/imx/imx-media-of.c
> b/drivers/staging/media/imx/imx-media-of.c
> index b026fe66467c..4aac42cb79a4 100644
> --- a/drivers/staging/media/imx/imx-media-of.c
> +++ b/drivers/staging/media/imx/imx-media-of.c
> @@ -115,7 +115,7 @@ of_parse_subdev(struct imx_media_dev *imxmd, struct
> device_node *sd_np,
>
> /* register this subdev with async notifier */
> imxsd = imx_media_add_async_subdev(imxmd, sd_np, NULL);
> - if (IS_ERR_OR_NULL(imxsd))
> + if (IS_ERR(imxsd))
> return imxsd;
... this changes behaviour:
imx-media: imx_media_of_parse failed with -17
imx-media: probe of capture-subsystem failed with error -17
We must continue to return NULL here if imxsd == -EEXIST:
- return imxsd;
+ return PTR_ERR(imxsd) == -EEXIST ? NULL : imxsd;
or change the code where of_parse_subdev is called (from
imx_media_of_parse, and recursively from of_parse_subdev) to not handle
the -EEXIST return value as an error.
With those fixed,
Reviewed-by: Philipp Zabel <p.za...@pengutronix.de>
Tested-by: Philipp Zabel <p.za...@pengutronix.de>
regards
Philipp
