Thread (3 messages) 3 messages, 2 authors, 2026-01-21
STALE187d

[PATCH] drm/atmel-hlcdc: don't reject the commit if the src rect has fractional parts

From: Ludovic Desroches <ludovic.desroches@microchip.com>
Date: 2025-11-20 10:39:32
Also in: dri-devel, lkml
Subsystem: drm drivers, drm drivers and misc gpu patches, drm drivers for atmel hlcdc, the rest · Maintainers: David Airlie, Simona Vetter, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Manikandan Muralidharan, Dharma Balasubiramani, Linus Torvalds

Don’t reject the commit when the source rectangle has fractional parts.
This can occur due to scaling: drm_atomic_helper_check_plane_state() calls
drm_rect_clip_scaled(), which may introduce fractional parts while
computing the clipped source rectangle. This does not imply the commit is
invalid, so we should accept it instead of discarding it.

Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
---
 drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_plane.c | 19 ++++---------------
 1 file changed, 4 insertions(+), 15 deletions(-)
diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_plane.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_plane.c
index 92132be9823f1e705d266f9547702ea9530bd043..bccfe055c087e5632d60503e8e4bcb3d9e18ce50 100644
--- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_plane.c
+++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_plane.c
@@ -79,8 +79,6 @@ drm_plane_state_to_atmel_hlcdc_plane_state(struct drm_plane_state *s)
 	return container_of(s, struct atmel_hlcdc_plane_state, base);
 }
 
-#define SUBPIXEL_MASK			0xffff
-
 static uint32_t rgb_formats[] = {
 	DRM_FORMAT_C8,
 	DRM_FORMAT_XRGB4444,
@@ -745,24 +743,15 @@ static int atmel_hlcdc_plane_atomic_check(struct drm_plane *p,
 	if (ret || !s->visible)
 		return ret;
 
-	hstate->src_x = s->src.x1;
-	hstate->src_y = s->src.y1;
-	hstate->src_w = drm_rect_width(&s->src);
-	hstate->src_h = drm_rect_height(&s->src);
+	hstate->src_x = s->src.x1 >> 16;
+	hstate->src_y = s->src.y1 >> 16;
+	hstate->src_w = drm_rect_width(&s->src) >> 16;
+	hstate->src_h = drm_rect_height(&s->src) >> 16;
 	hstate->crtc_x = s->dst.x1;
 	hstate->crtc_y = s->dst.y1;
 	hstate->crtc_w = drm_rect_width(&s->dst);
 	hstate->crtc_h = drm_rect_height(&s->dst);
 
-	if ((hstate->src_x | hstate->src_y | hstate->src_w | hstate->src_h) &
-	    SUBPIXEL_MASK)
-		return -EINVAL;
-
-	hstate->src_x >>= 16;
-	hstate->src_y >>= 16;
-	hstate->src_w >>= 16;
-	hstate->src_h >>= 16;
-
 	hstate->nplanes = fb->format->num_planes;
 	if (hstate->nplanes > ATMEL_HLCDC_LAYER_MAX_PLANES)
 		return -EINVAL;
---
base-commit: fe4d0dea039f2befb93f27569593ec209843b0f5
change-id: 20251119-lcd_scaling_fix-a4842d86307c

Best regards,
-- 
Ludovic Desroches [off-list ref]

Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help