The hotplug detection routine of i915 uses drm_helper_hpd_irq_event(). This helper can detect changing of status of connector, but it can not detect changing of edid. Following scenario requires detection of changing of edid.
1) plug display device to a connector 2) system suspend 3) unplug 1)'s display device and plug the other display device to a connector 4) system resume
It adds edid check routine when a connector status still remains as "connector_status_connected".
Testcase: igt/kms_chamelium/hdmi-edid-change-during-hibernate Testcase: igt/kms_chamelium/hdmi-edid-change-during-suspend Testcase: igt/kms_chamelium/dp-edid-change-during-hibernate Testcase: igt/kms_chamelium/dp-edid-change-during-suspend
Signed-off-by: Gwan-gyeong Mun gwan-gyeong.mun@intel.com --- drivers/gpu/drm/i915/intel_hotplug.c | 80 +++++++++++++++++++++++++++- 1 file changed, 79 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/intel_hotplug.c b/drivers/gpu/drm/i915/intel_hotplug.c index 648a13c6043c..b92b83d46ccc 100644 --- a/drivers/gpu/drm/i915/intel_hotplug.c +++ b/drivers/gpu/drm/i915/intel_hotplug.c @@ -507,6 +507,84 @@ void intel_hpd_init(struct drm_i915_private *dev_priv) } }
+/** + * intel_hpd_irq_event - hotplug processing + * @dev: drm_device + * + * Drivers can use this function to run a detect cycle on all connectors which + * have the DRM_CONNECTOR_POLL_HPD flag set in their &polled member. All other + * connectors are ignored, which is useful to avoid reprobing fixed panels. + * + * This function is useful for drivers which can't or don't track hotplug interrupts + * for each connector. This function is based on drm_helper_hpd_irq_event() helper + * function and besides it adds edid check routine when a connector status still + * remains as "connector_status_connected". + * + * Following scenario requires detection of changing of edid. + * 1) plug display device to a connector + * 2) system suspend + * 3) unplug 1)'s display device and plug the other display device to a connector + * 4) system resume + + * This function must be called from process context with no mode + * setting locks held. + * + * Note that a connector can be both polled and probed from the hotplug handler, + * in case the hotplug interrupt is known to be unreliable. + */ +static bool intel_hpd_irq_event(struct drm_device *dev) +{ + struct drm_connector *connector; + struct drm_connector_list_iter conn_iter; + enum drm_connector_status old_status, cur_status; + struct edid *old_edid; + bool changed = false; + + if (!dev->mode_config.poll_enabled) + return false; + + mutex_lock(&dev->mode_config.mutex); + drm_connector_list_iter_begin(dev, &conn_iter); + drm_for_each_connector_iter(connector, &conn_iter) { + /* Only handle HPD capable connectors. */ + if (!(connector->polled & DRM_CONNECTOR_POLL_HPD)) + continue; + + old_status = connector->status; + old_edid = to_intel_connector(connector)->detect_edid; + + cur_status = drm_helper_probe_detect(connector, NULL, false); + DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n", + connector->base.id, connector->name, + drm_get_connector_status_name(old_status), + drm_get_connector_status_name(cur_status)); + + if (old_status != cur_status) + changed = true; + + /* Check changing of edid when a connector status still remains + * as "connector_status_connected". */ + if (old_status == cur_status && + cur_status == connector_status_connected) { + struct edid *cur_edid = to_intel_connector(connector)->detect_edid; + + if (memcmp(old_edid, cur_edid, sizeof(*cur_edid)) != 0) { + changed = true; + DRM_DEBUG_KMS("[CONNECTOR:%d:%s] edid updated\n", + connector->base.id, + connector->name); + } + } + } + drm_connector_list_iter_end(&conn_iter); + mutex_unlock(&dev->mode_config.mutex); + + if (changed) + drm_kms_helper_hotplug_event(dev); + + return changed; +} + static void i915_hpd_poll_init_work(struct work_struct *work) { struct drm_i915_private *dev_priv = @@ -552,7 +630,7 @@ static void i915_hpd_poll_init_work(struct work_struct *work) * in the middle of disabling polling */ if (!enabled) - drm_helper_hpd_irq_event(dev); + intel_hpd_irq_event(dev); }
/**