# \[PATCH 1/2\] fbdev: simplefb: Add mono framebuffer format

- From: Sebastian Raase \<hidden\>
- Date: 2026-11-04 02:35:25 
- List: linux-fbdev
- Page: https://ratatoskr.run/linux-fbdev/2026/11/17857621
- Thread: https://ratatoskr.run/linux-fbdev/2026/11/17857622/t.md

```text
Add a new simple-framebuffer format for monochrome 1 bit-per-pixel
framebuffers. Monochrome framebuffers are not true color, so their
visual is set to FB_VISUAL_MONO10 (set pixels are bright).

Signed-off-by: Sebastian Raase <redacted>
---
 drivers/video/fbdev/simplefb.c         | 2 ++
 include/linux/platform_data/simplefb.h | 1 +
 2 files changed, 3 insertions(+)

diff --git a/drivers/video/fbdev/simplefb.c b/drivers/video/fbdev/simplefb.c
index 60e5dcec201f..4662101885ec 100644
--- a/drivers/video/fbdev/simplefb.c
+++ b/drivers/video/fbdev/simplefb.c
@@ -583,6 +583,8 @@ static int simplefb_probe(struct platform_device *pdev)
 	info->fix.smem_start = mem->start;
 	info->fix.smem_len = resource_size(mem);
 	info->fix.line_length = params.stride;
+	if (params.format->bits_per_pixel == 1)
+		info->fix.visual = FB_VISUAL_MONO10;
 
 	info->var = simplefb_var;
 	info->var.xres = params.width;
diff --git a/include/linux/platform_data/simplefb.h b/include/linux/platform_data/simplefb.h
index 4f94d52ac99f..9b6d822145c9 100644
--- a/include/linux/platform_data/simplefb.h
+++ b/include/linux/platform_data/simplefb.h
@@ -15,6 +15,7 @@
 /* format array, use it to initialize a "struct simplefb_format" array */
 #define SIMPLEFB_FORMATS \
 { \
+	{ "mono", 1, {0, 1}, {0, 1}, {0, 1}, {0, 0}, DRM_FORMAT_R1 }, \
 	{ "r5g6b5", 16, {11, 5}, {5, 6}, {0, 5}, {0, 0}, DRM_FORMAT_RGB565 }, \
 	{ "r5g5b5a1", 16, {11, 5}, {6, 5}, {1, 5}, {0, 1}, DRM_FORMAT_RGBA5551 }, \
 	{ "x1r5g5b5", 16, {10, 5}, {5, 5}, {0, 5}, {0, 0}, DRM_FORMAT_XRGB1555 }, \
-- 
2.47.3

```