drm/format-helper: Make conversion_buf_size() support sub-byte pixel fmts

There are DRM fourcc formats that have pixels smaller than a byte, but the
conversion_buf_size() function assumes that pixels are a multiple of bytes
and use the struct drm_format_info .cpp field to calculate the dst_pitch.

Instead, calculate it by using the bits per pixel (bpp) and divide it by 8
to account for formats that have sub-byte pixels.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Arthur Grillo <arthurgrillo@riseup.net>
Reviewed-by: Maíra Canal <mcanal@igalia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230307215039.346863-1-javierm@redhat.com

diff --git a/drivers/gpu/drm/tests/drm_format_helper_test.c b/drivers/gpu/drm/tests/drm_format_helper_test.c
index 9536829c6e3afbfeed5b95743de042899342c277..84b5cc29c8fcc8b34cb19abe73fa343ee333969c 100644 (file)
--- a/drivers/gpu/drm/tests/drm_format_helper_test.c
+++ b/drivers/gpu/drm/tests/drm_format_helper_test.c
@@ -409,12 +409,15 @@ static size_t conversion_buf_size(u32 dst_format, unsigned int dst_pitch,
                                  const struct drm_rect *clip)
 {
        const struct drm_format_info *dst_fi = drm_format_info(dst_format);
+       unsigned int bpp;
 
        if (!dst_fi)
                return -EINVAL;
 
-       if (!dst_pitch)
-               dst_pitch = drm_rect_width(clip) * dst_fi->cpp[0];
+       if (!dst_pitch) {
+               bpp = drm_format_info_bpp(dst_fi, 0);
+               dst_pitch = DIV_ROUND_UP(drm_rect_width(clip) * bpp, 8);
+       }
 
        return dst_pitch * drm_rect_height(clip);
 }