drm: move drm_mode_legacy_fb_format to drm_fourcc.c
It's part of the drm fourcc handling code, mapping the old depth/bpp
values to new fourcc codes.
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20160829082757.17913-6-daniel.vetter@ffwll.ch
diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c
index c81546c..29c56b4 100644
--- a/drivers/gpu/drm/drm_fourcc.c
+++ b/drivers/gpu/drm/drm_fourcc.c
@@ -36,6 +36,49 @@
}
/**
+ * drm_mode_legacy_fb_format - compute drm fourcc code from legacy description
+ * @bpp: bits per pixels
+ * @depth: bit depth per pixel
+ *
+ * Computes a drm fourcc pixel format code for the given @bpp/@depth values.
+ * Useful in fbdev emulation code, since that deals in those values.
+ */
+uint32_t drm_mode_legacy_fb_format(uint32_t bpp, uint32_t depth)
+{
+ uint32_t fmt;
+
+ switch (bpp) {
+ case 8:
+ fmt = DRM_FORMAT_C8;
+ break;
+ case 16:
+ if (depth == 15)
+ fmt = DRM_FORMAT_XRGB1555;
+ else
+ fmt = DRM_FORMAT_RGB565;
+ break;
+ case 24:
+ fmt = DRM_FORMAT_RGB888;
+ break;
+ case 32:
+ if (depth == 24)
+ fmt = DRM_FORMAT_XRGB8888;
+ else if (depth == 30)
+ fmt = DRM_FORMAT_XRGB2101010;
+ else
+ fmt = DRM_FORMAT_ARGB8888;
+ break;
+ default:
+ DRM_ERROR("bad bpp, assuming x8r8g8b8 pixel format\n");
+ fmt = DRM_FORMAT_XRGB8888;
+ break;
+ }
+
+ return fmt;
+}
+EXPORT_SYMBOL(drm_mode_legacy_fb_format);
+
+/**
* drm_get_format_name - return a string for drm fourcc format
* @format: format to compute name of
*