From 56cdd6fd3baeb1874e1b68b25c0179b04984df1a Mon Sep 17 00:00:00 2001
From: Tom Rix <trix@redhat.com>
Date: Thu, 3 Mar 2022 12:19:43 -0800
Subject: drm/bridge: anx7625: check the return on anx7625_aux_trans
Git-commit: d583e752732421b26fef0d65020565f3bef12248
Patch-mainline: v5.19-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
Clang static analysis reports this issue
anx7625.c:876:13: warning: The left operand of '&' is
a garbage value
if (!(bcap & 0xOA01)) {
~~~~ ^
bcap is only set by a successful call to
anx7625_aux_trans(). So check.
Fixes: cd1637c7e480 ("drm/bridge: anx7625: add HDCP support")
Signed-off-by: Tom Rix <trix@redhat.com>
Fixes: adca62ec370c ("drm/bridge: anx7625: Support reading edid through aux channel")
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220303201943.501746-1-trix@redhat.com
Reviewed-by: Robert Foss <robert.foss@linaro.org>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/bridge/analogix/anx7625.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 4043192c0369..69122bea4c1e 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -874,7 +874,10 @@ static int anx7625_hdcp_enable(struct anx7625_data *ctx)
}
/* Read downstream capability */
- anx7625_aux_trans(ctx, DP_AUX_NATIVE_READ, 0x68028, 1, &bcap);
+ ret = anx7625_aux_trans(ctx, DP_AUX_NATIVE_READ, 0x68028, 1, &bcap);
+ if (ret < 0)
+ return ret;
+
if (!(bcap & 0x01)) {
pr_warn("downstream not support HDCP 1.4, cap(%x).\n", bcap);
return 0;
--
2.38.1