[PATCH v2 1/2] drm: Remove plane hsub/vsub alignment requirement for core helpers

[Carlos Eduardo Gallo Filho]

The drm_format_info_plane_{height,width} functions was implemented using
regular division for the plane size calculation, which cause issues [1][2]
when used on contexts where the dimensions are misaligned with relation
to the subsampling factors. So, replace the regular division by the
DIV_ROUND_UP macro.

This allows these functions to be used in more drivers, making further
work to bring more core presence on them possible.

[1] http://patchwork.freedesktop.org/patch/msgid/20170321181218.10042-3-ville.syrjala@linux.intel.com
[2] https://patchwork.freedesktop.org/patch/msgid/20211026225105.2783797-2-imre.deak@intel.com

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos at disroot.org>
---
 include/drm/drm_fourcc.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/include/drm/drm_fourcc.h b/include/drm/drm_fourcc.h
index 532ae78ca747..ccf91daa4307 100644
--- a/include/drm/drm_fourcc.h
+++ b/include/drm/drm_fourcc.h
@@ -22,6 +22,7 @@
 #ifndef __DRM_FOURCC_H__
 #define __DRM_FOURCC_H__
 
+#include <linux/math.h>
 #include <linux/types.h>
 #include <uapi/drm/drm_fourcc.h>
 
@@ -279,7 +280,7 @@ int drm_format_info_plane_width(const struct drm_format_info *info, int width,
 	if (plane == 0)
 		return width;
 
-	return width / info->hsub;
+	return DIV_ROUND_UP(width, info->hsub);
 }
 
 /**
@@ -301,7 +302,7 @@ int drm_format_info_plane_height(const struct drm_format_info *info, int height,
 	if (plane == 0)
 		return height;
 
-	return height / info->vsub;
+	return DIV_ROUND_UP(height, info->vsub);
 }
 
 const struct drm_format_info *__drm_format_info(u32 format);
-- 
2.41.0