[PATCH] drm: Add DPMS ioctl

[Alex Ivanov]

Display power management should be available to user no matter whether
display server implements it or not and should be made server agnostic
(X.Org, Wayland compositor), without need of TTY change.

Reasons:
1. User implements an own universal power management daemon. He has no
interest to deal with server or switch to a free TTY, he wants to
turn off the monitor in a simple way, like he controls power of other
system components.
2. Some applications under X.Org like Electron-based ones like to
prevent screen goning off giving user no way to fix that.
3. Many fresh new Wayland compositors don't implement DPMS at all and
at the same time have TTY switch broken.

Signed-off-by: Alex Ivanov <gnidorah at ya.ru>
---
 drivers/gpu/drm/drm_crtc_internal.h |  2 ++
 drivers/gpu/drm/drm_ioctl.c         |  1 +
 drivers/gpu/drm/drm_mode_object.c   | 41 +++++++++++++++++++++++++++++++++++++
 include/uapi/drm/drm.h              |  1 +
 4 files changed, 45 insertions(+)

diff --git a/drivers/gpu/drm/drm_crtc_internal.h b/drivers/gpu/drm/drm_crtc_internal.h
index a43582076b20..120dd40a5210 100644
--- a/drivers/gpu/drm/drm_crtc_internal.h
+++ b/drivers/gpu/drm/drm_crtc_internal.h
@@ -122,6 +122,8 @@ int drm_mode_obj_get_properties_ioctl(struct drm_device *dev, void *data,
 				      struct drm_file *file_priv);
 int drm_mode_obj_set_property_ioctl(struct drm_device *dev, void *data,
 				    struct drm_file *file_priv);
+int drm_mode_connector_dpms_ioctl(struct drm_device *dev,
+				  void *data, struct drm_file *file_priv);
 
 /* drm_encoder.c */
 int drm_encoder_register_all(struct drm_device *dev);
diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c
index a9ae6dd2d593..2cec1a382c7b 100644
--- a/drivers/gpu/drm/drm_ioctl.c
+++ b/drivers/gpu/drm/drm_ioctl.c
@@ -632,6 +632,7 @@ static const struct drm_ioctl_desc drm_ioctls[] = {
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_mode_connector_property_set_ioctl, DRM_MASTER|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
+	DRM_IOCTL_DEF(DRM_IOCTL_MODE_DPMS, drm_mode_connector_dpms_ioctl, DRM_ROOT_ONLY|DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
 	DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb, DRM_CONTROL_ALLOW|DRM_UNLOCKED),
diff --git a/drivers/gpu/drm/drm_mode_object.c b/drivers/gpu/drm/drm_mode_object.c
index 1055533792f3..9006cca4f7f1 100644
--- a/drivers/gpu/drm/drm_mode_object.c
+++ b/drivers/gpu/drm/drm_mode_object.c
@@ -500,3 +500,44 @@ int drm_mode_obj_set_property_ioctl(struct drm_device *dev, void *data,
 	drm_mode_object_put(arg_obj);
 	return ret;
 }
+
+int drm_mode_connector_dpms_ioctl(struct drm_device *dev,
+				  void *data, struct drm_file *file_priv)
+{
+	struct drm_mode_connector_set_property *conn_set_prop = data;
+	struct drm_mode_obj_set_property obj_set_prop = {
+		.value = conn_set_prop->value,
+		.obj_id = conn_set_prop->connector_id,
+		.obj_type = DRM_MODE_OBJECT_CONNECTOR
+	};
+
+	struct drm_mode_obj_set_property *arg = &obj_set_prop;
+	struct drm_mode_object *arg_obj;
+	struct drm_property *property;
+	int ret = -EINVAL;
+
+	struct drm_connector *connector;
+
+	if (!drm_core_check_feature(dev, DRIVER_MODESET))
+		return -EINVAL;
+
+	arg_obj = drm_mode_object_find(dev, arg->obj_id, arg->obj_type);
+	if (!arg_obj)
+		return -ENOENT;
+
+	if (!arg_obj->properties)
+		goto out_unref;
+
+	/* XXX atomic */
+	connector = obj_to_connector(arg_obj);
+	property = connector->dev->mode_config.dpms_property;
+
+	if (drm_drv_uses_atomic_modeset(property->dev))
+		ret = set_property_atomic(arg_obj, property, arg->value);
+	else
+		ret = set_property_legacy(arg_obj, property, arg->value);
+
+out_unref:
+	drm_mode_object_put(arg_obj);
+	return ret;
+}
diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
index 97677cd6964d..f60c14af1bcc 100644
--- a/include/uapi/drm/drm.h
+++ b/include/uapi/drm/drm.h
@@ -862,6 +862,7 @@ extern "C" {
 #define DRM_IOCTL_SYNCOBJ_WAIT		DRM_IOWR(0xC3, struct drm_syncobj_wait)
 #define DRM_IOCTL_SYNCOBJ_RESET		DRM_IOWR(0xC4, struct drm_syncobj_array)
 #define DRM_IOCTL_SYNCOBJ_SIGNAL	DRM_IOWR(0xC5, struct drm_syncobj_array)
+#define DRM_IOCTL_MODE_DPMS		DRM_IOWR(0xC6, struct drm_mode_connector_set_property)
 
 /**
  * Device specific ioctls should only be in their respective headers
-- 
2.14.2