6.6-stable review patch. If anyone has any objections, please let me know.
------------------
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
@@ -56,13 +56,13 @@ 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;
@@ -78,9 +78,9 @@ 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;
