linux-kernel - [PATCH v3 07/12] drm/udl: Drop unneeded alignment

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Date:   Thu,  8 Sep 2022 11:51:10 +0200
From:   Takashi Iwai <tiwai@...e.de>
To:     Thomas Zimmermann <tzimmermann@...e.de>
Cc:     Daniel Vetter <daniel.vetter@...ll.ch>,
        dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org
Subject: [PATCH v3 07/12] drm/udl: Drop unneeded alignment

The alignment of damaged area was needed for the original udlfb driver
that tried to trim the superfluous copies between front and backend
buffers and handle data in long int.  It's not the case for udl DRM
driver, hence we can omit the whole unneeded alignment, as well as the
dead code.

Acked-by: Thomas Zimmermann <tzimmermann@...e.de>
Signed-off-by: Takashi Iwai <tiwai@...e.de>
---
 drivers/gpu/drm/udl/udl_modeset.c  | 28 +--------------------
 drivers/gpu/drm/udl/udl_transfer.c | 40 ------------------------------
 2 files changed, 1 insertion(+), 67 deletions(-)

diff --git a/drivers/gpu/drm/udl/udl_modeset.c b/drivers/gpu/drm/udl/udl_modeset.c
index cbdda2d8b882..c9b837ac26a7 100644
--- a/drivers/gpu/drm/udl/udl_modeset.c
+++ b/drivers/gpu/drm/udl/udl_modeset.c
@@ -242,28 +242,6 @@ static long udl_log_cpp(unsigned int cpp)
 	return __ffs(cpp);
 }
 
-static int udl_aligned_damage_clip(struct drm_rect *clip, int x, int y,
-				   int width, int height)
-{
-	int x1, x2;
-
-	if (WARN_ON_ONCE(x < 0) ||
-	    WARN_ON_ONCE(y < 0) ||
-	    WARN_ON_ONCE(width < 0) ||
-	    WARN_ON_ONCE(height < 0))
-		return -EINVAL;
-
-	x1 = ALIGN_DOWN(x, sizeof(unsigned long));
-	x2 = ALIGN(width + (x - x1), sizeof(unsigned long)) + x1;
-
-	clip->x1 = x1;
-	clip->y1 = y;
-	clip->x2 = x2;
-	clip->y2 = y + height;
-
-	return 0;
-}
-
 static int udl_handle_damage(struct drm_framebuffer *fb,
 			     const struct iosys_map *map,
 			     int x, int y, int width, int height)
@@ -281,11 +259,7 @@ static int udl_handle_damage(struct drm_framebuffer *fb,
 		return ret;
 	log_bpp = ret;
 
-	ret = udl_aligned_damage_clip(&clip, x, y, width, height);
-	if (ret)
-		return ret;
-	else if ((clip.x2 > fb->width) || (clip.y2 > fb->height))
-		return -EINVAL;
+	drm_rect_init(&clip, x, y, width, height);
 
 	ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
 	if (ret)
diff --git a/drivers/gpu/drm/udl/udl_transfer.c b/drivers/gpu/drm/udl/udl_transfer.c
index 176ef2a6a731..a431208dda85 100644
--- a/drivers/gpu/drm/udl/udl_transfer.c
+++ b/drivers/gpu/drm/udl/udl_transfer.c
@@ -25,46 +25,6 @@
 #define MIN_RAW_PIX_BYTES	2
 #define MIN_RAW_CMD_BYTES	(RAW_HEADER_BYTES + MIN_RAW_PIX_BYTES)
 
-/*
- * Trims identical data from front and back of line
- * Sets new front buffer address and width
- * And returns byte count of identical pixels
- * Assumes CPU natural alignment (unsigned long)
- * for back and front buffer ptrs and width
- */
-#if 0
-static int udl_trim_hline(const u8 *bback, const u8 **bfront, int *width_bytes)
-{
-	int j, k;
-	const unsigned long *back = (const unsigned long *) bback;
-	const unsigned long *front = (const unsigned long *) *bfront;
-	const int width = *width_bytes / sizeof(unsigned long);
-	int identical = width;
-	int start = width;
-	int end = width;
-
-	for (j = 0; j < width; j++) {
-		if (back[j] != front[j]) {
-			start = j;
-			break;
-		}
-	}
-
-	for (k = width - 1; k > j; k--) {
-		if (back[k] != front[k]) {
-			end = k+1;
-			break;
-		}
-	}
-
-	identical = start + (width - end);
-	*bfront = (u8 *) &front[start];
-	*width_bytes = (end - start) * sizeof(unsigned long);
-
-	return identical * sizeof(unsigned long);
-}
-#endif
-
 static inline u16 pixel32_to_be16(const uint32_t pixel)
 {
 	return (((pixel >> 3) & 0x001f) |
-- 
2.35.3