Commit 9bacd4b1 authored by Imre Deak's avatar Imre Deak

drm/i915/dp: Check error return during DPCD capability queries

The assumptions of these users of drm_dp_dpcd_readb() is that the passed
in output buffer won't change in case of error, but this isn't
guaranteed. Fix this by treating any error as the lack of the given
capability.

In case of DP_SINK_DEVICE_AUX_FRAME_SYNC_CAP an error would leave the
buffer uninitialized even with the above assumption.
Signed-off-by: default avatarImre Deak <imre.deak@intel.com>
Reviewed-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1494408113-379-2-git-send-email-imre.deak@intel.com
parent ed58570f
......@@ -3088,7 +3088,8 @@ static bool intel_dp_get_y_cord_status(struct intel_dp *intel_dp)
{
uint8_t psr_caps = 0;
drm_dp_dpcd_readb(&intel_dp->aux, DP_PSR_CAPS, &psr_caps);
if (drm_dp_dpcd_readb(&intel_dp->aux, DP_PSR_CAPS, &psr_caps) != 1)
return false;
return psr_caps & DP_PSR2_SU_Y_COORDINATE_REQUIRED;
}
......@@ -3096,9 +3097,9 @@ static bool intel_dp_get_colorimetry_status(struct intel_dp *intel_dp)
{
uint8_t dprx = 0;
drm_dp_dpcd_readb(&intel_dp->aux,
DP_DPRX_FEATURE_ENUMERATION_LIST,
&dprx);
if (drm_dp_dpcd_readb(&intel_dp->aux, DP_DPRX_FEATURE_ENUMERATION_LIST,
&dprx) != 1)
return false;
return dprx & DP_VSC_SDP_EXT_FOR_COLORIMETRY_SUPPORTED;
}
......@@ -3106,7 +3107,9 @@ static bool intel_dp_get_alpm_status(struct intel_dp *intel_dp)
{
uint8_t alpm_caps = 0;
drm_dp_dpcd_readb(&intel_dp->aux, DP_RECEIVER_ALPM_CAP, &alpm_caps);
if (drm_dp_dpcd_readb(&intel_dp->aux, DP_RECEIVER_ALPM_CAP,
&alpm_caps) != 1)
return false;
return alpm_caps & DP_ALPM_CAP;
}
......@@ -3679,9 +3682,10 @@ intel_edp_init_dpcd(struct intel_dp *intel_dp)
uint8_t frame_sync_cap;
dev_priv->psr.sink_support = true;
drm_dp_dpcd_readb(&intel_dp->aux,
if (drm_dp_dpcd_readb(&intel_dp->aux,
DP_SINK_DEVICE_AUX_FRAME_SYNC_CAP,
&frame_sync_cap);
&frame_sync_cap) != 1)
frame_sync_cap = 0;
dev_priv->psr.aux_frame_sync = frame_sync_cap ? true : false;
/* PSR2 needs frame sync as well */
dev_priv->psr.psr2_support = dev_priv->psr.aux_frame_sync;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment