@@ -3545,3 +3545,63 @@ int drm_format_plane_cpp(uint32_t format, int plane)
}
}
EXPORT_SYMBOL(drm_format_plane_cpp);
+
+/**
+ * drm_format_horz_chroma_subsampling - get the horizontal chroma subsampling factor
+ * @format: pixel format (DRM_FORMAT_*)
+ *
+ * RETURNS:
+ * The horizontal chroma subsampling factor for the
+ * specified pixel format.
+ */
+int drm_format_horz_chroma_subsampling(uint32_t format)
+{
+ switch (format) {
+ case DRM_FORMAT_YUV411:
+ case DRM_FORMAT_YVU411:
+ case DRM_FORMAT_YUV410:
+ case DRM_FORMAT_YVU410:
+ return 4;
+ case DRM_FORMAT_YUYV:
+ case DRM_FORMAT_YVYU:
+ case DRM_FORMAT_UYVY:
+ case DRM_FORMAT_VYUY:
+ case DRM_FORMAT_NV12:
+ case DRM_FORMAT_NV21:
+ case DRM_FORMAT_NV16:
+ case DRM_FORMAT_NV61:
+ case DRM_FORMAT_YUV422:
+ case DRM_FORMAT_YVU422:
+ case DRM_FORMAT_YUV420:
+ case DRM_FORMAT_YVU420:
+ return 2;
+ default:
+ return 1;
+ }
+}
+EXPORT_SYMBOL(drm_format_horz_chroma_subsampling);
+
+/**
+ * drm_format_vert_chroma_subsampling - get the vertical chroma subsampling factor
+ * @format: pixel format (DRM_FORMAT_*)
+ *
+ * RETURNS:
+ * The vertical chroma subsampling factor for the
+ * specified pixel format.
+ */
+int drm_format_vert_chroma_subsampling(uint32_t format)
+{
+ switch (format) {
+ case DRM_FORMAT_YUV410:
+ case DRM_FORMAT_YVU410:
+ return 4;
+ case DRM_FORMAT_YUV420:
+ case DRM_FORMAT_YVU420:
+ case DRM_FORMAT_NV12:
+ case DRM_FORMAT_NV21:
+ return 2;
+ default:
+ return 1;
+ }
+}
+EXPORT_SYMBOL(drm_format_vert_chroma_subsampling);
@@ -1028,5 +1028,7 @@ extern void drm_fb_get_bpp_depth(uint32_t format, unsigned int *depth,
int *bpp);
extern int drm_format_num_planes(uint32_t format);
extern int drm_format_plane_cpp(uint32_t format, int plane);
+extern int drm_format_horz_chroma_subsampling(uint32_t format);
+extern int drm_format_vert_chroma_subsampling(uint32_t format);
#endif /* __DRM_CRTC_H__ */