This is a note to let you know that I've just added the patch titled
drm/bridge: nxp-ptn3460: fix i2c_master_send() error checking
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-bridge-nxp-ptn3460-fix-i2c_master_send-error-checking.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 914437992876838662c968cb416f832110fb1093 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Date: Mon, 4 Dec 2023 15:29:00 +0300
Subject: drm/bridge: nxp-ptn3460: fix i2c_master_send() error checking
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
commit 914437992876838662c968cb416f832110fb1093 upstream.
The i2c_master_send/recv() functions return negative error codes or the
number of bytes that were able to be sent/received. This code has
two problems. 1) Instead of checking if all the bytes were sent or
received, it checks that at least one byte was sent or received.
2) If there was a partial send/receive then we should return a negative
error code but this code returns success.
Fixes: a9fe713d7d45 ("drm/bridge: Add PTN3460 bridge driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: Robert Foss <rfoss@xxxxxxxxxx>
Signed-off-by: Robert Foss <rfoss@xxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/0cdc2dce-ca89-451a-9774-1482ab2f4762@moroto.mountain
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/bridge/nxp-ptn3460.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
--- a/drivers/gpu/drm/bridge/nxp-ptn3460.c
+++ b/drivers/gpu/drm/bridge/nxp-ptn3460.c
@@ -66,13 +66,13 @@ static int ptn3460_read_bytes(struct ptn
ret = i2c_master_send(ptn_bridge->client, &addr, 1);
if (ret <= 0) {
DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
- return ret;
+ return ret ?: -EIO;
}
ret = i2c_master_recv(ptn_bridge->client, buf, len);
- if (ret <= 0) {
+ if (ret != len) {
DRM_ERROR("Failed to recv i2c data, ret=%d\n", ret);
- return ret;
+ return ret < 0 ? ret : -EIO;
}
return 0;
@@ -88,9 +88,9 @@ static int ptn3460_write_byte(struct ptn
buf[1] = val;
ret = i2c_master_send(ptn_bridge->client, buf, ARRAY_SIZE(buf));
- if (ret <= 0) {
+ if (ret != ARRAY_SIZE(buf)) {
DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
- return ret;
+ return ret < 0 ? ret : -EIO;
}
return 0;
Patches currently in stable-queue which might be from dan.carpenter@xxxxxxxxxx are
queue-4.19/drm-bridge-nxp-ptn3460-fix-i2c_master_send-error-checking.patch
