drm/imx: kill firstopen callback

This thing seems to do some kind of delayed setup. Really, real kms
drivers shouldn't do that at all. Either stuff needs to be dynamically
hotplugged or the driver setup sequence needs to be fixed.

This patch here just moves the setup at the very end of the driver
load callback, with the locking adjusted accordingly.

v2: Also move the corresponding put from ->lastclose to ->unload.

Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/staging/imx-drm/imx-drm-core.c

@@ -69,28 +69,20 @@ struct imx_drm_connector {
 	struct module				*owner;
 };
 
-static int imx_drm_driver_firstopen(struct drm_device *drm)
-{
-	if (!imx_drm_device_get())
-		return -EINVAL;
-
-	return 0;
-}
-
 static void imx_drm_driver_lastclose(struct drm_device *drm)
 {
 	struct imx_drm_device *imxdrm = drm->dev_private;
 
 	if (imxdrm->fbhelper)
 		drm_fbdev_cma_restore_mode(imxdrm->fbhelper);
-
-	imx_drm_device_put();
 }
 
 static int imx_drm_driver_unload(struct drm_device *drm)
 {
 	struct imx_drm_device *imxdrm = drm->dev_private;
 
+	imx_drm_device_put();
+
 	drm_mode_config_cleanup(imxdrm->drm);
 	drm_kms_helper_poll_fini(imxdrm->drm);
 
@@ -225,8 +217,6 @@ struct drm_device *imx_drm_device_get(void)
 	struct imx_drm_connector *con;
 	struct imx_drm_crtc *crtc;
 
-	mutex_lock(&imxdrm->mutex);
-
 	list_for_each_entry(enc, &imxdrm->encoder_list, list) {
 		if (!try_module_get(enc->owner)) {
 			dev_err(imxdrm->dev, "could not get module %s\n",
@@ -253,8 +243,6 @@ struct drm_device *imx_drm_device_get(void)
 
 	imxdrm->references++;
 
-	mutex_unlock(&imxdrm->mutex);
-
 	return imxdrm->drm;
 
 unwind_crtc:
@@ -446,6 +434,9 @@ static int imx_drm_driver_load(struct drm_device *drm, unsigned long flags)
 	 */
 	imxdrm->drm->vblank_disable_allowed = 1;
 
+	if (!imx_drm_device_get())
+		ret = -EINVAL;
+
 	ret = 0;
 
 err_init:
@@ -790,7 +781,6 @@ static struct drm_driver imx_drm_driver = {
 	.driver_features	= DRIVER_MODESET | DRIVER_GEM,
 	.load			= imx_drm_driver_load,
 	.unload			= imx_drm_driver_unload,
-	.firstopen		= imx_drm_driver_firstopen,
 	.lastclose		= imx_drm_driver_lastclose,
 	.gem_free_object	= drm_gem_cma_free_object,
 	.gem_vm_ops		= &drm_gem_cma_vm_ops,