drm: Constify drm_mode_config atomic helper private pointer

The drm_mode_config helper private field points to a structure of
function pointers that don't need to be modified at runtime. Make it
const.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Acked-by: Brian Starkey <brian.starkey@arm.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170102091613.6310-1-laurent.pinchart@ideasonboard.com
diff --git a/drivers/gpu/drm/arm/malidp_drv.c b/drivers/gpu/drm/arm/malidp_drv.c
index 5dfcdb0..a9608a2 100644
--- a/drivers/gpu/drm/arm/malidp_drv.c
+++ b/drivers/gpu/drm/arm/malidp_drv.c
@@ -100,7 +100,7 @@ static void malidp_atomic_commit_tail(struct drm_atomic_state *state)
 	drm_atomic_helper_cleanup_planes(drm, state);
 }
 
-static struct drm_mode_config_helper_funcs malidp_mode_config_helpers = {
+static const struct drm_mode_config_helper_funcs malidp_mode_config_helpers = {
 	.atomic_commit_tail = malidp_atomic_commit_tail,
 };
 
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index ace4485..cceb551 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1170,7 +1170,7 @@ EXPORT_SYMBOL(drm_atomic_helper_commit_tail);
 static void commit_tail(struct drm_atomic_state *old_state)
 {
 	struct drm_device *dev = old_state->dev;
-	struct drm_mode_config_helper_funcs *funcs;
+	const struct drm_mode_config_helper_funcs *funcs;
 
 	funcs = dev->mode_config.helper_private;
 
diff --git a/drivers/gpu/drm/imx/imx-drm-core.c b/drivers/gpu/drm/imx/imx-drm-core.c
index 65bd8b8..45dceb6 100644
--- a/drivers/gpu/drm/imx/imx-drm-core.c
+++ b/drivers/gpu/drm/imx/imx-drm-core.c
@@ -138,7 +138,7 @@ static void imx_drm_atomic_commit_tail(struct drm_atomic_state *state)
 	drm_atomic_helper_cleanup_planes(dev, state);
 }
 
-static struct drm_mode_config_helper_funcs imx_drm_mode_config_helpers = {
+static const struct drm_mode_config_helper_funcs imx_drm_mode_config_helpers = {
 	.atomic_commit_tail = imx_drm_atomic_commit_tail,
 };
 
diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_fb.c b/drivers/gpu/drm/rockchip/rockchip_drm_fb.c
index d5e1f86..200b35b 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_fb.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_fb.c
@@ -193,7 +193,7 @@ rockchip_atomic_commit_tail(struct drm_atomic_state *state)
 	drm_atomic_helper_cleanup_planes(dev, state);
 }
 
-static struct drm_mode_config_helper_funcs rockchip_mode_config_helpers = {
+static const struct drm_mode_config_helper_funcs rockchip_mode_config_helpers = {
 	.atomic_commit_tail = rockchip_atomic_commit_tail,
 };
 
diff --git a/drivers/gpu/drm/virtio/virtgpu_display.c b/drivers/gpu/drm/virtio/virtgpu_display.c
index fad5a1c..d51bd45 100644
--- a/drivers/gpu/drm/virtio/virtgpu_display.c
+++ b/drivers/gpu/drm/virtio/virtgpu_display.c
@@ -347,7 +347,7 @@ static void vgdev_atomic_commit_tail(struct drm_atomic_state *state)
 	drm_atomic_helper_cleanup_planes(dev, state);
 }
 
-static struct drm_mode_config_helper_funcs virtio_mode_config_helpers = {
+static const struct drm_mode_config_helper_funcs virtio_mode_config_helpers = {
 	.atomic_commit_tail = vgdev_atomic_commit_tail,
 };
 
diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
index 5a29978..6cd541d6 100644
--- a/include/drm/drm_mode_config.h
+++ b/include/drm/drm_mode_config.h
@@ -661,7 +661,7 @@ struct drm_mode_config {
 	/* cursor size */
 	uint32_t cursor_width, cursor_height;
 
-	struct drm_mode_config_helper_funcs *helper_private;
+	const struct drm_mode_config_helper_funcs *helper_private;
 };
 
 void drm_mode_config_init(struct drm_device *dev);