From 021e214947d5bdb2bf7b028d365365776d03afcd Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Mon, 4 Dec 2023 15:29:00 +0300 Subject: [PATCH] drm/bridge: nxp-ptn3460: fix i2c_master_send() error checking 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@vger.kernel.org Signed-off-by: Dan Carpenter Reviewed-by: Robert Foss Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/0cdc2dce-ca89-451a-9774-1482ab2f4762@moroto.mountain Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/bridge/nxp-ptn3460.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/bridge/nxp-ptn3460.c b/drivers/gpu/drm/bridge/nxp-ptn3460.c index d4a1cc5052c3..d1d812ec0f7a 100644 --- 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 ptn3460_bridge *ptn_bridge, char addr, 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 ptn3460_bridge *ptn_bridge, char addr, 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;