[PATCH] drm/loongson: Remove a useless check in cursor_plane_atomic_async_check()

From: Sui Jingfeng
Date: Mon Jul 10 2023 - 06:24:23 EST


Because smatch warnings:

drivers/gpu/drm/loongson/lsdc_plane.c:199
lsdc_cursor_plane_atomic_async_check()
warn: variable dereferenced before check 'state' (see line 180)

vim +/state +199 drivers/gpu/drm/loongson/lsdc_plane.c

174 static int
lsdc_cursor_plane_atomic_async_check(struct drm_plane *plane,
175 struct drm_atomic_state *state)
176 {
177 struct drm_plane_state *new_state;
178 struct drm_crtc_state *crtc_state;
179
180 new_state = drm_atomic_get_new_plane_state(state, plane);
^^^^^
state is dereferenced inside this function

181
182 if (!plane->state || !plane->state->fb) {
183 drm_dbg(plane->dev, "%s: state is NULL\n", plane->name);
184 return -EINVAL;
185 }
186
187 if (new_state->crtc_w != new_state->crtc_h) {
188 drm_dbg(plane->dev, "unsupported cursor size: %ux%u\n",
189 new_state->crtc_w, new_state->crtc_h);
190 return -EINVAL;
191 }
192
193 if (new_state->crtc_w != 64 && new_state->crtc_w != 32) {
194 drm_dbg(plane->dev, "unsupported cursor size: %ux%u\n",
195 new_state->crtc_w, new_state->crtc_h);
196 return -EINVAL;
197 }
198
199 if (state) {
^^^^^
Checked too late!

Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Closes: https://lore.kernel.org/r/202307100423.rV7D05Uq-lkp@xxxxxxxxx/
Signed-off-by: Sui Jingfeng <suijingfeng@xxxxxxxxxxx>
---
drivers/gpu/drm/loongson/lsdc_plane.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/loongson/lsdc_plane.c b/drivers/gpu/drm/loongson/lsdc_plane.c
index 2ab3db982aa3..0d5094633222 100644
--- a/drivers/gpu/drm/loongson/lsdc_plane.c
+++ b/drivers/gpu/drm/loongson/lsdc_plane.c
@@ -196,13 +196,7 @@ static int lsdc_cursor_plane_atomic_async_check(struct drm_plane *plane,
return -EINVAL;
}

- if (state) {
- crtc_state = drm_atomic_get_existing_crtc_state(state, new_state->crtc);
- } else {
- crtc_state = plane->crtc->state;
- drm_dbg(plane->dev, "%s: atomic state is NULL\n", plane->name);
- }
-
+ crtc_state = drm_atomic_get_existing_crtc_state(state, new_state->crtc);
if (!crtc_state->active)
return -EINVAL;

--
2.34.1