diff mbox series

drm/bridge: parade-ps8640: check return values in ps8640_aux_transfer()

Message ID 20210924152607.28580-1-tim.gardner@canonical.com (mailing list archive)
State Not Applicable
Headers show
Series drm/bridge: parade-ps8640: check return values in ps8640_aux_transfer() | expand

Commit Message

Tim Gardner Sept. 24, 2021, 3:26 p.m. UTC 
Coverity complains of an unused return code:

CID 120459 (#1 of 1): Unchecked return value (CHECKED_RETURN)
7. check_return: Calling regmap_bulk_write without checking return value (as is
done elsewhere 199 out of 291 times).
204        regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
205                          ARRAY_SIZE(addr_len));

While I was at it I noticed 2 other places where return codes were not being
used, or used incorrectly (which is a real bug).

Fix these errors by correctly using the returned error codes.

Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
Cc: Syed Nayyar Waris <syednwaris@gmail.com>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Neil Armstrong <narmstrong@baylibre.com>
Cc: Robert Foss <robert.foss@linaro.org>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Jonas Karlman <jonas@kwiboo.se>
Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: linux-iio@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
---
 drivers/gpu/drm/bridge/parade-ps8640.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

Comments

Tim Gardner Sept. 24, 2021, 4:03 p.m. UTC | #1 
On 9/24/21 9:26 AM, Tim Gardner wrote:
> Coverity complains of an unused return code:
> 
> CID 120459 (#1 of 1): Unchecked return value (CHECKED_RETURN)
> 7. check_return: Calling regmap_bulk_write without checking return value (as is
> done elsewhere 199 out of 291 times).
> 204        regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
> 205                          ARRAY_SIZE(addr_len));
> 
> While I was at it I noticed 2 other places where return codes were not being
> used, or used incorrectly (which is a real bug).
> 
> Fix these errors by correctly using the returned error codes.
> 
> Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
> Cc: Syed Nayyar Waris <syednwaris@gmail.com>
> Cc: Andrzej Hajda <a.hajda@samsung.com>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Robert Foss <robert.foss@linaro.org>
> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> Cc: Jonas Karlman <jonas@kwiboo.se>
> Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: linux-iio@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Cc: dri-devel@lists.freedesktop.org
> Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
> ---
>   drivers/gpu/drm/bridge/parade-ps8640.c | 14 +++++++++++---
>   1 file changed, 11 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
> index 3aaa90913bf8..591da962970a 100644
> --- a/drivers/gpu/drm/bridge/parade-ps8640.c
> +++ b/drivers/gpu/drm/bridge/parade-ps8640.c
> @@ -201,8 +201,12 @@ static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
>   	addr_len[PAGE0_SWAUX_LENGTH - base] = (len == 0) ? SWAUX_NO_PAYLOAD :
>   					      ((len - 1) & SWAUX_LENGTH_MASK);
>   
> -	regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
> +	ret = regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
>   			  ARRAY_SIZE(addr_len));
> +	if (ret) {
> +		DRM_DEV_ERROR(dev, "failed to bulk write ADDR_7_0: %d\n", ret);
> +		return ret;
> +	}
>   
>   	if (len && (request == DP_AUX_NATIVE_WRITE ||
>   		    request == DP_AUX_I2C_WRITE)) {
> @@ -218,13 +222,17 @@ static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
>   		}
>   	}
>   
> -	regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
> +	ret = regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
> +	if (ret) {
> +		DRM_DEV_ERROR(dev, "failed to write SEND: %d\n", ret);
> +		return ret;
> +	}
>   
>   	/* Zero delay loop because i2c transactions are slow already */
>   	regmap_read_poll_timeout(map, PAGE0_SWAUX_CTRL, data,
>   				 !(data & SWAUX_SEND), 0, 50 * 1000);
>   
> -	regmap_read(map, PAGE0_SWAUX_STATUS, &data);
> +	ret = regmap_read(map, PAGE0_SWAUX_STATUS, &data);
>   	if (ret) {
>   		DRM_DEV_ERROR(dev, "failed to read PAGE0_SWAUX_STATUS: %d\n",
>   			      ret);
> 

I forgot to mention this patch is for linux-next next-20210924.

-----------
Tim Gardner
Canonical, Inc
William Breathitt Gray Sept. 25, 2021, 12:45 a.m. UTC | #2 
On Fri, Sep 24, 2021 at 10:03:27AM -0600, Tim Gardner wrote:
> 
> 
> On 9/24/21 9:26 AM, Tim Gardner wrote:
> > Coverity complains of an unused return code:
> > 
> > CID 120459 (#1 of 1): Unchecked return value (CHECKED_RETURN)
> > 7. check_return: Calling regmap_bulk_write without checking return value (as is
> > done elsewhere 199 out of 291 times).
> > 204        regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
> > 205                          ARRAY_SIZE(addr_len));
> > 
> > While I was at it I noticed 2 other places where return codes were not being
> > used, or used incorrectly (which is a real bug).
> > 
> > Fix these errors by correctly using the returned error codes.
> > 
> > Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
> > Cc: Syed Nayyar Waris <syednwaris@gmail.com>
> > Cc: Andrzej Hajda <a.hajda@samsung.com>
> > Cc: Neil Armstrong <narmstrong@baylibre.com>
> > Cc: Robert Foss <robert.foss@linaro.org>
> > Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> > Cc: Jonas Karlman <jonas@kwiboo.se>
> > Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
> > Cc: David Airlie <airlied@linux.ie>
> > Cc: Daniel Vetter <daniel@ffwll.ch>
> > Cc: linux-iio@vger.kernel.org
> > Cc: linux-kernel@vger.kernel.org
> > Cc: dri-devel@lists.freedesktop.org
> > Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
> > ---
> >   drivers/gpu/drm/bridge/parade-ps8640.c | 14 +++++++++++---
> >   1 file changed, 11 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
> > index 3aaa90913bf8..591da962970a 100644
> > --- a/drivers/gpu/drm/bridge/parade-ps8640.c
> > +++ b/drivers/gpu/drm/bridge/parade-ps8640.c
> > @@ -201,8 +201,12 @@ static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
> >   	addr_len[PAGE0_SWAUX_LENGTH - base] = (len == 0) ? SWAUX_NO_PAYLOAD :
> >   					      ((len - 1) & SWAUX_LENGTH_MASK);
> >   
> > -	regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
> > +	ret = regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
> >   			  ARRAY_SIZE(addr_len));
> > +	if (ret) {
> > +		DRM_DEV_ERROR(dev, "failed to bulk write ADDR_7_0: %d\n", ret);
> > +		return ret;
> > +	}
> >   
> >   	if (len && (request == DP_AUX_NATIVE_WRITE ||
> >   		    request == DP_AUX_I2C_WRITE)) {
> > @@ -218,13 +222,17 @@ static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
> >   		}
> >   	}
> >   
> > -	regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
> > +	ret = regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
> > +	if (ret) {
> > +		DRM_DEV_ERROR(dev, "failed to write SEND: %d\n", ret);
> > +		return ret;
> > +	}
> >   
> >   	/* Zero delay loop because i2c transactions are slow already */
> >   	regmap_read_poll_timeout(map, PAGE0_SWAUX_CTRL, data,
> >   				 !(data & SWAUX_SEND), 0, 50 * 1000);
> >   
> > -	regmap_read(map, PAGE0_SWAUX_STATUS, &data);
> > +	ret = regmap_read(map, PAGE0_SWAUX_STATUS, &data);
> >   	if (ret) {
> >   		DRM_DEV_ERROR(dev, "failed to read PAGE0_SWAUX_STATUS: %d\n",
> >   			      ret);
> > 
> 
> I forgot to mention this patch is for linux-next next-20210924.
> 
> -----------
> Tim Gardner
> Canonical, Inc

Hi Tim,

For future patches, the git format-patch command has a useful option
'--base'. It will allow you to provide the base tree information for
users and maintainers so that they know where to apply the patch:
https://git-scm.com/docs/git-format-patch#_base_tree_information

Sincerely,

William Breathitt Gray
Robert Foss Oct. 11, 2021, 10:07 a.m. UTC | #3 
Hey Tim,

Thanks for submitting this.

I'm seeing some checkpatch --strict warnings. Could you fix them and
resubmit the series?

On Fri, 24 Sept 2021 at 17:26, Tim Gardner <tim.gardner@canonical.com> wrote:
>
> Coverity complains of an unused return code:
>
> CID 120459 (#1 of 1): Unchecked return value (CHECKED_RETURN)
> 7. check_return: Calling regmap_bulk_write without checking return value (as is

Checkpatch is unhappy about the length of this line.

> done elsewhere 199 out of 291 times).
> 204        regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
> 205                          ARRAY_SIZE(addr_len));
>
> While I was at it I noticed 2 other places where return codes were not being
> used, or used incorrectly (which is a real bug).
>
> Fix these errors by correctly using the returned error codes.
>
> Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
> Cc: Syed Nayyar Waris <syednwaris@gmail.com>
> Cc: Andrzej Hajda <a.hajda@samsung.com>
> Cc: Neil Armstrong <narmstrong@baylibre.com>
> Cc: Robert Foss <robert.foss@linaro.org>
> Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
> Cc: Jonas Karlman <jonas@kwiboo.se>
> Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
> Cc: David Airlie <airlied@linux.ie>
> Cc: Daniel Vetter <daniel@ffwll.ch>
> Cc: linux-iio@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Cc: dri-devel@lists.freedesktop.org
> Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
> ---
>  drivers/gpu/drm/bridge/parade-ps8640.c | 14 +++++++++++---
>  1 file changed, 11 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
> index 3aaa90913bf8..591da962970a 100644
> --- a/drivers/gpu/drm/bridge/parade-ps8640.c
> +++ b/drivers/gpu/drm/bridge/parade-ps8640.c
> @@ -201,8 +201,12 @@ static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
>         addr_len[PAGE0_SWAUX_LENGTH - base] = (len == 0) ? SWAUX_NO_PAYLOAD :
>                                               ((len - 1) & SWAUX_LENGTH_MASK);
>
> -       regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
> +       ret = regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
>                           ARRAY_SIZE(addr_len));

Align to open parenthesis.

> +       if (ret) {
> +               DRM_DEV_ERROR(dev, "failed to bulk write ADDR_7_0: %d\n", ret);
> +               return ret;
> +       }
>
>         if (len && (request == DP_AUX_NATIVE_WRITE ||
>                     request == DP_AUX_I2C_WRITE)) {
> @@ -218,13 +222,17 @@ static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
>                 }
>         }
>
> -       regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
> +       ret = regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
> +       if (ret) {
> +               DRM_DEV_ERROR(dev, "failed to write SEND: %d\n", ret);
> +               return ret;
> +       }
>
>         /* Zero delay loop because i2c transactions are slow already */
>         regmap_read_poll_timeout(map, PAGE0_SWAUX_CTRL, data,
>                                  !(data & SWAUX_SEND), 0, 50 * 1000);
>
> -       regmap_read(map, PAGE0_SWAUX_STATUS, &data);
> +       ret = regmap_read(map, PAGE0_SWAUX_STATUS, &data);
>         if (ret) {
>                 DRM_DEV_ERROR(dev, "failed to read PAGE0_SWAUX_STATUS: %d\n",
>                               ret);
> --
> 2.33.0
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c
index 3aaa90913bf8..591da962970a 100644
--- a/drivers/gpu/drm/bridge/parade-ps8640.c
+++ b/drivers/gpu/drm/bridge/parade-ps8640.c
@@ -201,8 +201,12 @@  static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
 	addr_len[PAGE0_SWAUX_LENGTH - base] = (len == 0) ? SWAUX_NO_PAYLOAD :
 					      ((len - 1) & SWAUX_LENGTH_MASK);
 
-	regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
+	ret = regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, addr_len,
 			  ARRAY_SIZE(addr_len));
+	if (ret) {
+		DRM_DEV_ERROR(dev, "failed to bulk write ADDR_7_0: %d\n", ret);
+		return ret;
+	}
 
 	if (len && (request == DP_AUX_NATIVE_WRITE ||
 		    request == DP_AUX_I2C_WRITE)) {
@@ -218,13 +222,17 @@  static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
 		}
 	}
 
-	regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
+	ret = regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
+	if (ret) {
+		DRM_DEV_ERROR(dev, "failed to write SEND: %d\n", ret);
+		return ret;
+	}
 
 	/* Zero delay loop because i2c transactions are slow already */
 	regmap_read_poll_timeout(map, PAGE0_SWAUX_CTRL, data,
 				 !(data & SWAUX_SEND), 0, 50 * 1000);
 
-	regmap_read(map, PAGE0_SWAUX_STATUS, &data);
+	ret = regmap_read(map, PAGE0_SWAUX_STATUS, &data);
 	if (ret) {
 		DRM_DEV_ERROR(dev, "failed to read PAGE0_SWAUX_STATUS: %d\n",
 			      ret);