Merge remote-tracking branch 'drm/drm-next' into drm-misc-next

[sfrench/cifs-2.6.git] / include / drm / drm_connector.h

diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 5b3cf909fd5e4c31072a849572db66a87565e2aa..dd0552cb747232cc7ac89003c6af846d6b90a0e5 100644 (file)
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -82,6 +82,53 @@ enum drm_connector_status {
        connector_status_unknown = 3,
 };
 
+/**
+ * enum drm_connector_registration_status - userspace registration status for
+ * a &drm_connector
+ *
+ * This enum is used to track the status of initializing a connector and
+ * registering it with userspace, so that DRM can prevent bogus modesets on
+ * connectors that no longer exist.
+ */
+enum drm_connector_registration_state {
+       /**
+        * @DRM_CONNECTOR_INITIALIZING: The connector has just been created,
+        * but has yet to be exposed to userspace. There should be no
+        * additional restrictions to how the state of this connector may be
+        * modified.
+        */
+       DRM_CONNECTOR_INITIALIZING = 0,
+
+       /**
+        * @DRM_CONNECTOR_REGISTERED: The connector has been fully initialized
+        * and registered with sysfs, as such it has been exposed to
+        * userspace. There should be no additional restrictions to how the
+        * state of this connector may be modified.
+        */
+       DRM_CONNECTOR_REGISTERED = 1,
+
+       /**
+        * @DRM_CONNECTOR_UNREGISTERED: The connector has either been exposed
+        * to userspace and has since been unregistered and removed from
+        * userspace, or the connector was unregistered before it had a chance
+        * to be exposed to userspace (e.g. still in the
+        * @DRM_CONNECTOR_INITIALIZING state). When a connector is
+        * unregistered, there are additional restrictions to how its state
+        * may be modified:
+        *
+        * - An unregistered connector may only have its DPMS changed from
+        *   On->Off. Once DPMS is changed to Off, it may not be switched back
+        *   to On.
+        * - Modesets are not allowed on unregistered connectors, unless they
+        *   would result in disabling its assigned CRTCs. This means
+        *   disabling a CRTC on an unregistered connector is OK, but enabling
+        *   one is not.
+        * - Removing a CRTC from an unregistered connector is OK, but new
+        *   CRTCs may never be assigned to an unregistered connector.
+        */
+       DRM_CONNECTOR_UNREGISTERED = 2,
+};
+
 enum subpixel_order {
        SubPixelUnknown = 0,
        SubPixelHorizontalRGB,
@@ -853,10 +900,12 @@ struct drm_connector {
        bool ycbcr_420_allowed;
 
        /**
-        * @registered: Is this connector exposed (registered) with userspace?
+        * @registration_state: Is this connector initializing, exposed
+        * (registered) with userspace, or unregistered?
+        *
         * Protected by @mutex.
         */
-       bool registered;
+       enum drm_connector_registration_state registration_state;
 
        /**
         * @modes:
@@ -1167,6 +1216,24 @@ static inline void drm_connector_unreference(struct drm_connector *connector)
        drm_connector_put(connector);
 }
 
+/**
+ * drm_connector_is_unregistered - has the connector been unregistered from
+ * userspace?
+ * @connector: DRM connector
+ *
+ * Checks whether or not @connector has been unregistered from userspace.
+ *
+ * Returns:
+ * True if the connector was unregistered, false if the connector is
+ * registered or has not yet been registered with userspace.
+ */
+static inline bool
+drm_connector_is_unregistered(struct drm_connector *connector)
+{
+       return READ_ONCE(connector->registration_state) ==
+               DRM_CONNECTOR_UNREGISTERED;
+}
+
 const char *drm_get_connector_status_name(enum drm_connector_status status);
 const char *drm_get_subpixel_order_name(enum subpixel_order order);
 const char *drm_get_dpms_name(int val);