drm: Add drm_format_plane_cpp() utility function
This function returns the bytes per pixel value based on the pixel
format and plane index.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 32ab669..2c4e9cf 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -3498,3 +3498,48 @@
}
}
EXPORT_SYMBOL(drm_format_num_planes);
+
+/**
+ * drm_format_plane_cpp - determine the bytes per pixel value
+ * @format: pixel format (DRM_FORMAT_*)
+ * @plane: plane index
+ *
+ * RETURNS:
+ * The bytes per pixel value for the specified plane.
+ */
+int drm_format_plane_cpp(uint32_t format, int plane)
+{
+ unsigned int depth;
+ int bpp;
+
+ if (plane >= drm_format_num_planes(format))
+ return 0;
+
+ switch (format) {
+ case DRM_FORMAT_YUYV:
+ case DRM_FORMAT_YVYU:
+ case DRM_FORMAT_UYVY:
+ case DRM_FORMAT_VYUY:
+ return 2;
+ case DRM_FORMAT_NV12:
+ case DRM_FORMAT_NV21:
+ case DRM_FORMAT_NV16:
+ case DRM_FORMAT_NV61:
+ return plane ? 2 : 1;
+ case DRM_FORMAT_YUV410:
+ case DRM_FORMAT_YVU410:
+ case DRM_FORMAT_YUV411:
+ case DRM_FORMAT_YVU411:
+ case DRM_FORMAT_YUV420:
+ case DRM_FORMAT_YVU420:
+ case DRM_FORMAT_YUV422:
+ case DRM_FORMAT_YVU422:
+ case DRM_FORMAT_YUV444:
+ case DRM_FORMAT_YVU444:
+ return 1;
+ default:
+ drm_fb_get_bpp_depth(format, &depth, &bpp);
+ return bpp >> 3;
+ }
+}
+EXPORT_SYMBOL(drm_format_plane_cpp);