From aa656d48e871a1b062e1bbf9474d8b831c35074c Mon Sep 17 00:00:00 2001
From: Liu Ying <victor.liu@nxp.com>
Date: Mon, 12 Jun 2023 17:23:59 +0800
Subject: [PATCH] drm/mxsfb: Disable overlay plane in mxsfb_plane_overlay_atomic_disable()
Git-commit: aa656d48e871a1b062e1bbf9474d8b831c35074c
Patch-mainline: v6.6-rc1
References: git-fixes
When disabling overlay plane in mxsfb_plane_overlay_atomic_update(),
overlay plane's framebuffer pointer is NULL. So, dereferencing it would
cause a kernel Oops(NULL pointer dereferencing). Fix the issue by
disabling overlay plane in mxsfb_plane_overlay_atomic_disable() instead.
Fixes: cb285a5348e7 ("drm: mxsfb: Replace mxsfb_get_fb_paddr() with drm_fb_cma_get_gem_addr()")
Cc: stable@vger.kernel.org # 5.19+
Signed-off-by: Liu Ying <victor.liu@nxp.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230612092359.784115-1-victor.liu@nxp.com
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/mxsfb/mxsfb_kms.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/drivers/gpu/drm/mxsfb/mxsfb_kms.c b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
index 3bcc9c0f2019..7ed2516b6de0 100644
--- a/drivers/gpu/drm/mxsfb/mxsfb_kms.c
+++ b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
@@ -611,6 +611,14 @@ static void mxsfb_plane_overlay_atomic_update(struct drm_plane *plane,
writel(ctrl, mxsfb->base + LCDC_AS_CTRL);
}
+static void mxsfb_plane_overlay_atomic_disable(struct drm_plane *plane,
+ struct drm_atomic_state *state)
+{
+ struct mxsfb_drm_private *mxsfb = to_mxsfb_drm_private(plane->dev);
+
+ writel(0, mxsfb->base + LCDC_AS_CTRL);
+}
+
static bool mxsfb_format_mod_supported(struct drm_plane *plane,
uint32_t format,
uint64_t modifier)
@@ -626,6 +634,7 @@ static const struct drm_plane_helper_funcs mxsfb_plane_primary_helper_funcs = {
static const struct drm_plane_helper_funcs mxsfb_plane_overlay_helper_funcs = {
.atomic_check = mxsfb_plane_atomic_check,
.atomic_update = mxsfb_plane_overlay_atomic_update,
+ .atomic_disable = mxsfb_plane_overlay_atomic_disable,
};
static const struct drm_plane_funcs mxsfb_plane_funcs = {
--
2.35.3