[PATCH v4] fbtft: Improve damage_range to mark only changed rows Instead of marking the entire display as dirty, calculate start_row and end_row based on off/len and mark only those rows. This improves performance for partial framebuffer updates.
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From: ChanSoo Shin <hidden>
Date: 2026-01-28 15:01:10
Also in:
dri-devel, linux-staging
Subsystem:
fbtft framebuffer drivers, staging subsystem, the rest · Maintainers:
Andy Shevchenko, Greg Kroah-Hartman, Linus Torvalds
Signed-off-by: ChanSoo Shin <redacted> --- drivers/staging/fbtft/fbtft-core.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c
index 8a5ccc8ae0a1..0fbdfdaaa94d 100644
--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c@@ -415,8 +415,11 @@ static void fbtft_ops_damage_range(struct fb_info *info, off_t off, size_t len) { struct fbtft_par *par = info->par; - /* TODO: only mark changed area update all for now */ - par->fbtftops.mkdirty(info, -1, 0); + __u32 width = info->var.xres; + __u32 start_row = off / width; + __u32 end_row = (off + len - 1) / width; + + par->fbtftops.mkdirty(info, start_row, end_row); } static void fbtft_ops_damage_area(struct fb_info *info, u32 x, u32 y, u32 width, u32 height)
--
2.52.0