[PATCH] drm/rockchip: vop: Fix color for RGB888/BGR888 format on VOP full

[Jonas Karlman]

Use of DRM_FORMAT_RGB888 and DRM_FORMAT_BGR888 on e.g. RK3288, RK3328
and RK3399 result in wrong colors being displayed.

The issue can be observed using modetest:

  modetest -s <connector_id>@<crtc_id>:1920x1080-60 at RG24
  modetest -s <connector_id>@<crtc_id>:1920x1080-60 at BG24

Vendor 4.4 kernel apply an inverted rb swap for these formats on VOP
full (major = 3).

Fix colors by applying rb swap similar to vendor 4.4 kernel.

Signed-off-by: Jonas Karlman <jonas at kwiboo.se>
---
 drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
index b3d0b6ae9294..a1ce09a22f83 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
@@ -247,14 +247,17 @@ static inline void vop_cfg_done(struct vop *vop)
 	VOP_REG_SET(vop, common, cfg_done, 1);
 }
 
-static bool has_rb_swapped(uint32_t format)
+static bool has_rb_swapped(uint32_t version, uint32_t format)
 {
 	switch (format) {
 	case DRM_FORMAT_XBGR8888:
 	case DRM_FORMAT_ABGR8888:
-	case DRM_FORMAT_BGR888:
 	case DRM_FORMAT_BGR565:
 		return true;
+	case DRM_FORMAT_RGB888:
+		return VOP_MAJOR(version) == 3;
+	case DRM_FORMAT_BGR888:
+		return VOP_MAJOR(version) != 3;
 	default:
 		return false;
 	}
@@ -1035,7 +1038,7 @@ static void vop_plane_atomic_update(struct drm_plane *plane,
 	VOP_WIN_SET(vop, win, dsp_info, dsp_info);
 	VOP_WIN_SET(vop, win, dsp_st, dsp_st);
 
-	rb_swap = has_rb_swapped(fb->format->format);
+	rb_swap = has_rb_swapped(vop->data->version, fb->format->format);
 	VOP_WIN_SET(vop, win, rb_swap, rb_swap);
 
 	/*
-- 
2.42.0