@@ -30,6 +30,11 @@
#define STM_MAX_FB_WIDTH 2048
#define STM_MAX_FB_HEIGHT 2048 /* same as width to handle orientation */
+static uint stm_bpp = 16;
+
+MODULE_PARM_DESC(bpp, "bits-per-pixel (default: 16)");
+module_param_named(bpp, stm_bpp, uint, 0644);
+
static const struct drm_mode_config_funcs drv_mode_config_funcs = {
.fb_create = drm_gem_fb_create,
.atomic_check = drm_atomic_helper_check,
@@ -93,6 +98,7 @@ static int drv_load(struct drm_device *ddev)
ddev->mode_config.min_height = 0;
ddev->mode_config.max_width = STM_MAX_FB_WIDTH;
ddev->mode_config.max_height = STM_MAX_FB_HEIGHT;
+ ddev->mode_config.preferred_depth = stm_bpp;
ddev->mode_config.funcs = &drv_mode_config_funcs;
ddev->mode_config.normalize_zpos = true;
@@ -203,7 +209,7 @@ static int stm_drm_platform_probe(struct platform_device *pdev)
if (ret)
goto err_put;
- drm_fbdev_dma_setup(ddev, 16);
+ drm_fbdev_dma_setup(ddev, stm_bpp);
return 0;
Boards that use the STM32F{4,7} series have limited amounts of RAM. The added parameter allows users to size, within certain limits, the memory footprint required by the framebuffer. Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com> --- (no changes since v1) drivers/gpu/drm/stm/drv.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)