Re: [PATCH] drm/bridge: nxp-ptn3460: simplify some error checking

[Robert Foss]

On Wed, 6 Dec 2023 18:05:15 +0300, Dan Carpenter wrote:
> The i2c_master_send/recv() functions return negative error codes or
> they return "len" on success.  So the error handling here can be written
> as just normal checks for "if (ret < 0) return ret;".  No need to
> complicate things.
> 
> Btw, in this code the "len" parameter can never be zero, but even if
> it were, then I feel like this would still be the best way to write it.
> 
> [...]

Added suggested by tag, to reflect Neils feedback.

Applied, thanks!

[1/1] drm/bridge: nxp-ptn3460: simplify some error checking
  https://cgit.freedesktop.org/drm/drm-misc/commit/?id=28d3d0696688



Rob

[PATCH] drm/bridge: nxp-ptn3460: simplify some error checking

[Dan Carpenter]

The i2c_master_send/recv() functions return negative error codes or
they return "len" on success.  So the error handling here can be written
as just normal checks for "if (ret < 0) return ret;".  No need to
complicate things.

Btw, in this code the "len" parameter can never be zero, but even if
it were, then I feel like this would still be the best way to write it.

Fixes: 914437992876 ("drm/bridge: nxp-ptn3460: fix i2c_master_send() error 
checking")
Signed-off-by: Dan Carpenter 
---
This is not really a bug fix but I added a Fixes tag because I don't
want people to pull my other commit without also applying this.

 drivers/gpu/drm/bridge/nxp-ptn3460.c | 12 ++--
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/bridge/nxp-ptn3460.c 
b/drivers/gpu/drm/bridge/nxp-ptn3460.c
index 9b7eb8c669c1..7c0076e49953 100644
--- a/drivers/gpu/drm/bridge/nxp-ptn3460.c
+++ b/drivers/gpu/drm/bridge/nxp-ptn3460.c
@@ -54,15 +54,15 @@ static int ptn3460_read_bytes(struct ptn3460_bridge 
*ptn_bridge, char addr,
int ret;
 
ret = i2c_master_send(ptn_bridge->client, , 1);
-   if (ret <= 0) {
+   if (ret < 0) {
DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
-   return ret ?: -EIO;
+   return ret;
}
 
ret = i2c_master_recv(ptn_bridge->client, buf, len);
-   if (ret != len) {
+   if (ret < 0) {
DRM_ERROR("Failed to recv i2c data, ret=%d\n", ret);
-   return ret < 0 ? ret : -EIO;
+   return ret;
}
 
return 0;
@@ -78,9 +78,9 @@ static int ptn3460_write_byte(struct ptn3460_bridge 
*ptn_bridge, char addr,
buf[1] = val;
 
ret = i2c_master_send(ptn_bridge->client, buf, ARRAY_SIZE(buf));
-   if (ret != ARRAY_SIZE(buf)) {
+   if (ret < 0) {
DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
-   return ret < 0 ? ret : -EIO;
+   return ret;
}
 
return 0;
-- 
2.42.0