imx-drm: imx-drm-core: kill off mutex

This mutex doesn't protect anything anymore; get rid of it.
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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

@@ -40,14 +40,12 @@ struct imx_drm_device {
 	struct drm_device			*drm;
 	struct device				*dev;
 	struct imx_drm_crtc			*crtc[MAX_CRTC];
-	struct mutex				mutex;
 	int					pipes;
 	struct drm_fbdev_cma			*fbhelper;
 };
 
 struct imx_drm_crtc {
 	struct drm_crtc				*crtc;
-	struct imx_drm_device			*imxdrm;
 	int					pipe;
 	struct imx_drm_crtc_helper_funcs	imx_drm_helper_funcs;
 	struct crtc_cookie			cookie;
@@ -270,8 +268,6 @@ static int imx_drm_driver_load(struct drm_device *drm, unsigned long flags)
 
 	drm_mode_config_init(drm);
 
-	mutex_lock(&imxdrm->mutex);
-
 	drm_kms_helper_poll_init(drm);
 
 	ret = drm_vblank_init(drm, MAX_CRTC);
@@ -287,12 +283,10 @@ static int imx_drm_driver_load(struct drm_device *drm, unsigned long flags)
 
 	platform_set_drvdata(drm->platformdev, drm);
 
-	mutex_unlock(&imxdrm->mutex);
-
 	/* Now try and bind all our sub-components */
 	ret = component_bind_all(drm->dev, drm);
 	if (ret)
-		goto err_relock;
+		goto err_vblank;
 
 	/*
 	 * All components are now added, we can publish the connector sysfs
@@ -332,13 +326,11 @@ static int imx_drm_driver_load(struct drm_device *drm, unsigned long flags)
 
 err_unbind:
 	component_unbind_all(drm->dev, drm);
-err_relock:
-	mutex_lock(&imxdrm->mutex);
+err_vblank:
 	drm_vblank_cleanup(drm);
 err_kms:
 	drm_kms_helper_poll_fini(drm);
 	drm_mode_config_cleanup(drm);
-	mutex_unlock(&imxdrm->mutex);
 
 	return ret;
 }
@@ -358,8 +350,6 @@ int imx_drm_add_crtc(struct drm_device *drm, struct drm_crtc *crtc,
 	struct imx_drm_crtc *imx_drm_crtc;
 	int ret;
 
-	mutex_lock(&imxdrm->mutex);
-
 	/*
 	 * The vblank arrays are dimensioned by MAX_CRTC - we can't
 	 * pass IDs greater than this to those functions.
@@ -386,7 +376,6 @@ int imx_drm_add_crtc(struct drm_device *drm, struct drm_crtc *crtc,
 	imx_drm_crtc->cookie.id = id;
 	imx_drm_crtc->mux_id = imx_drm_crtc->pipe;
 	imx_drm_crtc->crtc = crtc;
-	imx_drm_crtc->imxdrm = imxdrm;
 
 	imxdrm->crtc[imx_drm_crtc->pipe] = imx_drm_crtc;
 
@@ -402,8 +391,6 @@ int imx_drm_add_crtc(struct drm_device *drm, struct drm_crtc *crtc,
 	drm_crtc_init(drm, crtc,
 			imx_drm_crtc->imx_drm_helper_funcs.crtc_funcs);
 
-	mutex_unlock(&imxdrm->mutex);
-
 	return 0;
 
 err_register:
@@ -411,7 +398,6 @@ int imx_drm_add_crtc(struct drm_device *drm, struct drm_crtc *crtc,
 	kfree(imx_drm_crtc);
 err_alloc:
 err_busy:
-	mutex_unlock(&imxdrm->mutex);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(imx_drm_add_crtc);
@@ -421,16 +407,12 @@ EXPORT_SYMBOL_GPL(imx_drm_add_crtc);
  */
 int imx_drm_remove_crtc(struct imx_drm_crtc *imx_drm_crtc)
 {
-	struct imx_drm_device *imxdrm = imx_drm_crtc->imxdrm;
-
-	mutex_lock(&imxdrm->mutex);
+	struct imx_drm_device *imxdrm = imx_drm_crtc->crtc->dev->dev_private;
 
 	drm_crtc_cleanup(imx_drm_crtc->crtc);
 
 	imxdrm->crtc[imx_drm_crtc->pipe] = NULL;
 
-	mutex_unlock(&imxdrm->mutex);
-
 	kfree(imx_drm_crtc);
 
 	return 0;
@@ -657,8 +639,6 @@ static int __init imx_drm_init(void)
 	if (!imx_drm_device)
 		return -ENOMEM;
 
-	mutex_init(&imx_drm_device->mutex);
-
 	ret = platform_driver_register(&imx_drm_pdrv);
 	if (ret)
 		goto err_pdrv;