1 files changed, 95 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index b142ac260d97..764401951041 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -807,3 +807,98 @@ int drm_helper_resume_force_mode(struct drm_device *dev)
         return 0;
 }
 EXPORT_SYMBOL(drm_helper_resume_force_mode);
+
+static struct slow_work_ops output_poll_ops;
+
+#define DRM_OUTPUT_POLL_PERIOD (10*HZ)
+static void output_poll_execute(struct slow_work *work)
+{
+        struct delayed_slow_work *delayed_work = container_of(work, struct delayed_slow_work, work);
+        struct drm_device *dev = container_of(delayed_work, struct drm_device, mode_config.output_poll_slow_work);
+        struct drm_connector *connector;
+        enum drm_connector_status old_status, status;
+        bool repoll = false, changed = false;
+        int ret;
+
+        mutex_lock(&dev->mode_config.mutex);
+        list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+
+                /* if this is HPD or polled don't check it -
+                   TV out for instance */
+                if (!connector->polled)
+                        continue;
+
+                else if (connector->polled & (DRM_CONNECTOR_POLL_CONNECT | DRM_CONNECTOR_POLL_DISCONNECT))
+                        repoll = true;
+
+                old_status = connector->status;
+                /* if we are connected and don't want to poll for disconnect
+                   skip it */
+                if (old_status == connector_status_connected &&
+                    !(connector->polled & DRM_CONNECTOR_POLL_DISCONNECT) &&
+                    !(connector->polled & DRM_CONNECTOR_POLL_HPD))
+                        continue;
+
+                status = connector->funcs->detect(connector);
+                if (old_status != status)
+                        changed = true;
+        }
+
+        mutex_unlock(&dev->mode_config.mutex);
+
+        if (changed) {
+                /* send a uevent + call fbdev */
+                drm_sysfs_hotplug_event(dev);
+                if (dev->mode_config.funcs->output_poll_changed)
+                        dev->mode_config.funcs->output_poll_changed(dev);
+        }
+
+        if (repoll) {
+                ret = delayed_slow_work_enqueue(delayed_work, DRM_OUTPUT_POLL_PERIOD);
+                if (ret)
+                        DRM_ERROR("delayed enqueue failed %d\n", ret);
+        }
+}
+
+void drm_kms_helper_poll_init(struct drm_device *dev)
+{
+        struct drm_connector *connector;
+        bool poll = false;
+        int ret;
+
+        list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
+                if (connector->polled)
+                        poll = true;
+        }
+        slow_work_register_user(THIS_MODULE);
+        delayed_slow_work_init(&dev->mode_config.output_poll_slow_work,
+                               &output_poll_ops);
+
+        if (poll) {
+                ret = delayed_slow_work_enqueue(&dev->mode_config.output_poll_slow_work, DRM_OUTPUT_POLL_PERIOD);
+                if (ret)
+                        DRM_ERROR("delayed enqueue failed %d\n", ret);
+        }
+}
+EXPORT_SYMBOL(drm_kms_helper_poll_init);
+
+void drm_kms_helper_poll_fini(struct drm_device *dev)
+{
+        delayed_slow_work_cancel(&dev->mode_config.output_poll_slow_work);
+        slow_work_unregister_user(THIS_MODULE);
+}
+EXPORT_SYMBOL(drm_kms_helper_poll_fini);
+
+void drm_helper_hpd_irq_event(struct drm_device *dev)
+{
+        if (!dev->mode_config.poll_enabled)
+                return;
+        delayed_slow_work_cancel(&dev->mode_config.output_poll_slow_work);
+        /* schedule a slow work asap */
+        delayed_slow_work_enqueue(&dev->mode_config.output_poll_slow_work, 0);
+}
+EXPORT_SYMBOL(drm_helper_hpd_irq_event);
+
+static struct slow_work_ops output_poll_ops = {
+        .execute = output_poll_execute,
+};