Sometimes it's useful for users of the DP AUX bus (like panels) to be able to poll HPD. Let's add a callback that allows DP AUX busses drivers to provide this.
Suggested-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Signed-off-by: Douglas Anderson dianders@chromium.org ---
include/drm/dp/drm_dp_helper.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/include/drm/dp/drm_dp_helper.h b/include/drm/dp/drm_dp_helper.h index dad1442c91df..a12951319573 100644 --- a/include/drm/dp/drm_dp_helper.h +++ b/include/drm/dp/drm_dp_helper.h @@ -2021,6 +2021,20 @@ struct drm_dp_aux { ssize_t (*transfer)(struct drm_dp_aux *aux, struct drm_dp_aux_msg *msg);
+ /** + * @is_hpd_asserted: returns true if HPD is asserted + * + * This is mainly useful for eDP panels drivers to query whether + * an eDP panel has finished powering on. This is an optional function. + * + * NOTE: this function specifically reports the state of the HPD pin + * that's associated with the DP AUX channel. This is different from + * the HPD concept in much of the rest of DRM which is more about + * physical presence of a display. For eDP, for instance, a display is + * assumed always present even if the HPD pin is deasserted. + */ + bool (*is_hpd_asserted)(struct drm_dp_aux *aux); + /** * @i2c_nack_count: Counts I2C NACKs, used for DP validation. */