From: Tom Rix Date: Thu, 3 Mar 2022 20:19:43 +0000 (-0800) Subject: drm/bridge: anx7625: check the return on anx7625_aux_trans X-Git-Tag: v6.1-rc5~617^2^2~454 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d583e752732421b26fef0d65020565f3bef12248;p=platform%2Fkernel%2Flinux-starfive.git drm/bridge: anx7625: check the return on anx7625_aux_trans 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 Fixes: adca62ec370c ("drm/bridge: anx7625: Support reading edid through aux channel") Signed-off-by: Robert Foss Link: https://patchwork.freedesktop.org/patch/msgid/20220303201943.501746-1-trix@redhat.com Reviewed-by: Robert Foss --- diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c index 4043192..69122be 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;