drm/i915/sdvo: Actually print the reason why the SDVO command failed

It's much easier to figure out why the SDVO encoder refuses to cooperate
if we can see what status we got back.

v2: Zero initialize only the first character, not the whole buffer

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> #v1
Link: https://patchwork.freedesktop.org/patch/msgid/20190410170941.28142-1-ville.syrjala@linux.intel.com

diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
index 6d78fd1656423223ed79bfa8fef82047486c67b9..0860ae36bb875b1c5125a4a40ea58ea047401b1a 100644 (file)
--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -522,6 +522,7 @@ static bool intel_sdvo_read_response(struct intel_sdvo *intel_sdvo,
 #define BUF_LEN 256
        char buffer[BUF_LEN];
 
+       buffer[0] = '\0';
 
        /*
         * The documentation states that all commands will be
@@ -585,7 +586,8 @@ static bool intel_sdvo_read_response(struct intel_sdvo *intel_sdvo,
        return true;
 
 log_fail:
-       DRM_DEBUG_KMS("%s: R: ... failed\n", SDVO_NAME(intel_sdvo));
+       DRM_DEBUG_KMS("%s: R: ... failed %s\n",
+                     SDVO_NAME(intel_sdvo), buffer);
        return false;
 }