The hotplug detection routine of drm_helper_hpd_irq_event() 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".
v2: Add NULL check before comparing of EDIDs. v3: Make it as part of existing drm_helper_hpd_irq_event() (Stan, Mika)
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/drm_probe_helper.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c index a1bb157bfdfa..2705a5a0e4d6 100644 --- a/drivers/gpu/drm/drm_probe_helper.c +++ b/drivers/gpu/drm/drm_probe_helper.c @@ -742,7 +742,16 @@ EXPORT_SYMBOL(drm_kms_helper_poll_fini); * panels. * * This helper function is useful for drivers which can't or don't track hotplug - * interrupts for each connector. + * interrupts for each connector. And it also supports a detection of changing + * of edid on between suspend and resume 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 * * Drivers which support hotplug interrupts for each connector individually and * which have a more fine-grained detect logic should bypass this code and @@ -760,6 +769,7 @@ bool drm_helper_hpd_irq_event(struct drm_device *dev) struct drm_connector *connector; struct drm_connector_list_iter conn_iter; enum drm_connector_status old_status; + struct edid *old_edid; bool changed = false;
if (!dev->mode_config.poll_enabled) @@ -773,6 +783,7 @@ bool drm_helper_hpd_irq_event(struct drm_device *dev) continue;
old_status = connector->status; + old_edid = connector->detect_edid;
connector->status = drm_helper_probe_detect(connector, NULL, false); DRM_DEBUG_KMS("[CONNECTOR:%d:%s] status updated from %s to %s\n", @@ -782,6 +793,22 @@ bool drm_helper_hpd_irq_event(struct drm_device *dev) drm_get_connector_status_name(connector->status)); if (old_status != connector->status) changed = true; + + /* Check changing of edid when a connector status still remains + * as "connector_status_connected". + */ + if (old_status == connector->status && + old_status == connector_status_connected) { + if (!old_edid || !connector->detect_edid) + continue; + + if (memcmp(old_edid, connector->detect_edid, sizeof(*old_edid))) { + 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);