[PATCH 6/8] drm/fb-helper: Pass buffer format via drm_fb_helper_surface_size

From: Geert Uytterhoeven
Date: Thu Jul 13 2023 - 09:17:36 EST


drm_fb_helper_single_fb_probe() first calls drm_fb_helper_find_sizes(),
followed by drm_fbdev_generic_helper_fb_probe():
- The former tries to find a suitable buffer format, taking into
account limitations of the whole display pipeline,
- The latter just calls drm_mode_legacy_fb_format() again.

Simplify this by passing the buffer format between these functions
via a new buffer format member in the drm_fb_helper_surface_size
structure.

Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
---
drivers/gpu/drm/drm_fb_helper.c | 1 +
drivers/gpu/drm/drm_fbdev_generic.c | 9 ++++-----
include/drm/drm_fb_helper.h | 2 ++
3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 61a5d450cc20ef0a..e870b2ce7a8625e3 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -1564,6 +1564,7 @@ static int __drm_fb_helper_find_sizes(struct drm_fb_helper *fb_helper,
info = drm_format_info(surface_format);
sizes->surface_bpp = drm_format_info_bpp(info, 0);
sizes->surface_depth = info->depth;
+ sizes->surface_format = surface_format;

/* first up get a count of crtcs now in use and new min/maxes width/heights */
crtc_count = 0;
diff --git a/drivers/gpu/drm/drm_fbdev_generic.c b/drivers/gpu/drm/drm_fbdev_generic.c
index 98ae703848a02fa3..953056896c1a5652 100644
--- a/drivers/gpu/drm/drm_fbdev_generic.c
+++ b/drivers/gpu/drm/drm_fbdev_generic.c
@@ -77,16 +77,15 @@ static int drm_fbdev_generic_helper_fb_probe(struct drm_fb_helper *fb_helper,
struct fb_info *info;
size_t screen_size;
void *screen_buffer;
- u32 format;
int ret;

- drm_dbg_kms(dev, "surface width(%d), height(%d) and bpp(%d)\n",
+ drm_info(dev, "surface width(%d), height(%d), bpp(%d) and format(%p4cc)\n",
sizes->surface_width, sizes->surface_height,
- sizes->surface_bpp);
+ sizes->surface_bpp, &sizes->surface_format);

- format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
buffer = drm_client_framebuffer_create(client, sizes->surface_width,
- sizes->surface_height, format);
+ sizes->surface_height,
+ sizes->surface_format);
if (IS_ERR(buffer))
return PTR_ERR(buffer);

diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h
index 4863b0f8299e89b6..430a17b530fa49e6 100644
--- a/include/drm/drm_fb_helper.h
+++ b/include/drm/drm_fb_helper.h
@@ -45,6 +45,7 @@ struct drm_fb_helper;
* @surface_height: scanout buffer height
* @surface_bpp: scanout buffer bpp
* @surface_depth: scanout buffer depth
+ * @surface_format: scanout buffer format (optional)
*
* Note that the scanout surface width/height may be larger than the fbdev
* width/height. In case of multiple displays, the scanout surface is sized
@@ -61,6 +62,7 @@ struct drm_fb_helper_surface_size {
u32 surface_height;
u32 surface_bpp;
u32 surface_depth;
+ u32 surface_format;
};

/**
--
2.34.1