@@ -654,10 +654,12 @@ static int drm_dp_i2c_do_msg(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg)
case DP_AUX_I2C_REPLY_NACK:
DRM_DEBUG_KMS("I2C nack\n");
+ aux->i2c_nack_count++;
return -EREMOTEIO;
case DP_AUX_I2C_REPLY_DEFER:
DRM_DEBUG_KMS("I2C defer\n");
+ aux->i2c_defer_count++;
usleep_range(400, 500);
continue;
@@ -551,6 +551,7 @@ struct drm_dp_aux {
struct mutex hw_mutex;
ssize_t (*transfer)(struct drm_dp_aux *aux,
struct drm_dp_aux_msg *msg);
+ uint8_t i2c_nack_count, i2c_defer_count;
};
ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset,
These counters are used for Displayort complinace testing to detect error conditions when executing certain compliance tests. Currently these are used in the EDID tests to determine if the video mode needs to be set to the preferred mode or the failsafe mode. Cc: dri-devel@lists.freedesktop.org Signed-off-by: Todd Previte <tprevite@gmail.com> --- drivers/gpu/drm/drm_dp_helper.c | 2 ++ include/drm/drm_dp_helper.h | 1 + 2 files changed, 3 insertions(+)