Revert "drm/probe-helpers: Drop locking from poll_enable"

This reverts commit 3846fd9b86001bea171943cc3bb9222cb6da6b42.

There were some precursor commits missing for this around connector
locking, we should probably merge Lyude's nouveau avoid the problem patch.

diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
index b452a7ccd84b8ca4752f1dfb6828bd697eeed6b7..cf8f0128c161ed6e1034322066c49d53a80b9e92 100644 (file)
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -115,27 +115,24 @@ static int drm_helper_probe_add_cmdline_mode(struct drm_connector *connector)
 
 #define DRM_OUTPUT_POLL_PERIOD (10*HZ)
 /**
- * drm_kms_helper_poll_enable - re-enable output polling.
+ * drm_kms_helper_poll_enable_locked - re-enable output polling.
  * @dev: drm_device
  *
- * This function re-enables the output polling work, after it has been
- * temporarily disabled using drm_kms_helper_poll_disable(), for example over
- * suspend/resume.
+ * This function re-enables the output polling work without
+ * locking the mode_config mutex.
  *
- * Drivers can call this helper from their device resume implementation. It is
- * an error to call this when the output polling support has not yet been set
- * up.
- *
- * Note that calls to enable and disable polling must be strictly ordered, which
- * is automatically the case when they're only call from suspend/resume
- * callbacks.
+ * This is like drm_kms_helper_poll_enable() however it is to be
+ * called from a context where the mode_config mutex is locked
+ * already.
  */
-void drm_kms_helper_poll_enable(struct drm_device *dev)
+void drm_kms_helper_poll_enable_locked(struct drm_device *dev)
 {
        bool poll = false;
        struct drm_connector *connector;
        unsigned long delay = DRM_OUTPUT_POLL_PERIOD;
 
+       WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
+
        if (!dev->mode_config.poll_enabled || !drm_kms_helper_poll)
                return;
 
@@ -163,7 +160,7 @@ void drm_kms_helper_poll_enable(struct drm_device *dev)
        if (poll)
                schedule_delayed_work(&dev->mode_config.output_poll_work, delay);
 }
-EXPORT_SYMBOL(drm_kms_helper_poll_enable);
+EXPORT_SYMBOL(drm_kms_helper_poll_enable_locked);
 
 static enum drm_connector_status
 drm_connector_detect(struct drm_connector *connector, bool force)
@@ -290,7 +287,7 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector,
 
        /* Re-enable polling in case the global poll config changed. */
        if (drm_kms_helper_poll != dev->mode_config.poll_running)
-               drm_kms_helper_poll_enable(dev);
+               drm_kms_helper_poll_enable_locked(dev);
 
        dev->mode_config.poll_running = drm_kms_helper_poll;
 
@@ -482,12 +479,8 @@ out:
  * This function disables the output polling work.
  *
  * Drivers can call this helper from their device suspend implementation. It is
- * not an error to call this even when output polling isn't enabled or already
- * disabled. Polling is re-enabled by calling drm_kms_helper_poll_enable().
- *
- * Note that calls to enable and disable polling must be strictly ordered, which
- * is automatically the case when they're only call from suspend/resume
- * callbacks.
+ * not an error to call this even when output polling isn't enabled or arlready
+ * disabled.
  */
 void drm_kms_helper_poll_disable(struct drm_device *dev)
 {
@@ -497,6 +490,24 @@ void drm_kms_helper_poll_disable(struct drm_device *dev)
 }
 EXPORT_SYMBOL(drm_kms_helper_poll_disable);
 
+/**
+ * drm_kms_helper_poll_enable - re-enable output polling.
+ * @dev: drm_device
+ *
+ * This function re-enables the output polling work.
+ *
+ * Drivers can call this helper from their device resume implementation. It is
+ * an error to call this when the output polling support has not yet been set
+ * up.
+ */
+void drm_kms_helper_poll_enable(struct drm_device *dev)
+{
+       mutex_lock(&dev->mode_config.mutex);
+       drm_kms_helper_poll_enable_locked(dev);
+       mutex_unlock(&dev->mode_config.mutex);
+}
+EXPORT_SYMBOL(drm_kms_helper_poll_enable);
+
 /**
  * drm_kms_helper_poll_init - initialize and enable output polling
  * @dev: drm_device

diff --git a/drivers/gpu/drm/i915/intel_hotplug.c b/drivers/gpu/drm/i915/intel_hotplug.c
index b62e3f8ad415f6173470c90a3cb1b35b04f91c4b..3d546c019de058c4a925d2a689f2bf4b9ff2c6f7 100644 (file)
--- a/drivers/gpu/drm/i915/intel_hotplug.c
+++ b/drivers/gpu/drm/i915/intel_hotplug.c
@@ -180,7 +180,7 @@ static void intel_hpd_irq_storm_disable(struct drm_i915_private *dev_priv)
 
        /* Enable polling and queue hotplug re-enabling. */
        if (hpd_disabled) {
-               drm_kms_helper_poll_enable(dev);
+               drm_kms_helper_poll_enable_locked(dev);
                mod_delayed_work(system_wq, &dev_priv->hotplug.reenable_work,
                                 msecs_to_jiffies(HPD_STORM_REENABLE_DELAY));
        }
@@ -511,7 +511,7 @@ static void i915_hpd_poll_init_work(struct work_struct *work)
        }
 
        if (enabled)
-               drm_kms_helper_poll_enable(dev);
+               drm_kms_helper_poll_enable_locked(dev);
 
        mutex_unlock(&dev->mode_config.mutex);
 

diff --git a/include/drm/drm_crtc_helper.h b/include/drm/drm_crtc_helper.h
index d026f5017c33cea2c9766b28b5ccb67d635fbe85..982c299e435a09703de12d32b4deec08a54d44e0 100644 (file)
--- a/include/drm/drm_crtc_helper.h
+++ b/include/drm/drm_crtc_helper.h
@@ -73,5 +73,6 @@ extern void drm_kms_helper_hotplug_event(struct drm_device *dev);
 
 extern void drm_kms_helper_poll_disable(struct drm_device *dev);
 extern void drm_kms_helper_poll_enable(struct drm_device *dev);
+extern void drm_kms_helper_poll_enable_locked(struct drm_device *dev);
 
 #endif