drm/fourcc: Pass the format_info pointer to drm_format_plane_width/height

So far, the drm_format_plane_height/width functions were operating on the
format's fourcc and was doing a lookup to retrieve the drm_format_info
structure and return the cpp.

However, this is inefficient since in most cases, we will have the
drm_format_info pointer already available so we shouldn't have to perform a
new lookup. Some drm_fourcc functions also already operate on the
drm_format_info pointer for that reason, so the API is quite inconsistent
there.

Let's follow the latter pattern and remove the extra lookup while being a
bit more consistent.

In order to be extra consistent, also rename that function to
drm_format_info_plane_cpp and to a static function in the header to match
the current policy. The parameters order have also be changed to match the
other functions prototype.

Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/514af1d489d80b8b1767e3716b663ce5103da6eb.1558002671.git-series.maxime.ripard@bootlin.com

1 files changed, 44 insertions, 2 deletions

diff --git a/include/drm/drm_fourcc.h b/include/drm/drm_fourcc.h
index 6b5a82b31bc4..4ef8ccb5d236 100644
--- a/include/drm/drm_fourcc.h
+++ b/include/drm/drm_fourcc.h
@@ -277,6 +277,50 @@ int drm_format_info_plane_cpp(const struct drm_format_info *info, int plane)
 	return info->cpp[plane];
 }
 
+/**
+ * drm_format_info_plane_width - width of the plane given the first plane
+ * @format: pixel format info
+ * @width: width of the first plane
+ * @plane: plane index
+ *
+ * Returns:
+ * The width of @plane, given that the width of the first plane is @width.
+ */
+static inline
+int drm_format_info_plane_width(const struct drm_format_info *info, int width,
+				int plane)
+{
+	if (!info || plane >= info->num_planes)
+		return 0;
+
+	if (plane == 0)
+		return width;
+
+	return width / info->hsub;
+}
+
+/**
+ * drm_format_info_plane_height - height of the plane given the first plane
+ * @format: pixel format info
+ * @height: height of the first plane
+ * @plane: plane index
+ *
+ * Returns:
+ * The height of @plane, given that the height of the first plane is @height.
+ */
+static inline
+int drm_format_info_plane_height(const struct drm_format_info *info, int height,
+				 int plane)
+{
+	if (!info || plane >= info->num_planes)
+		return 0;
+
+	if (plane == 0)
+		return height;
+
+	return height / info->vsub;
+}
+
 const struct drm_format_info *__drm_format_info(u32 format);
 const struct drm_format_info *drm_format_info(u32 format);
 const struct drm_format_info *
@@ -285,8 +329,6 @@ drm_get_format_info(struct drm_device *dev,
 uint32_t drm_mode_legacy_fb_format(uint32_t bpp, uint32_t depth);
 uint32_t drm_driver_legacy_fb_format(struct drm_device *dev,
 				     uint32_t bpp, uint32_t depth);
-int drm_format_plane_width(int width, uint32_t format, int plane);
-int drm_format_plane_height(int height, uint32_t format, int plane);
 unsigned int drm_format_info_block_width(const struct drm_format_info *info,
 					 int plane);
 unsigned int drm_format_info_block_height(const struct drm_format_info *info,