DRM: ARC: PGU: fix framebuffer format switching

Current implementation don't switch to RGB565 format if BGR888 was
previously used. Fix that.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

diff --git a/drivers/gpu/drm/arc/arcpgu_crtc.c b/drivers/gpu/drm/arc/arcpgu_crtc.c
index dfaddbb..31d9824 100644 (file)
--- a/drivers/gpu/drm/arc/arcpgu_crtc.c
+++ b/drivers/gpu/drm/arc/arcpgu_crtc.c
@@ -32,6 +32,7 @@ static void arc_pgu_set_pxl_fmt(struct drm_crtc *crtc)
        uint32_t pixel_format = fb->format->format;
        struct simplefb_format *format = NULL;
        int i;
+       u32 reg_ctrl;
 
        for (i = 0; i < ARRAY_SIZE(supported_formats); i++) {
                if (supported_formats[i].fourcc == pixel_format)
@@ -41,11 +42,12 @@ static void arc_pgu_set_pxl_fmt(struct drm_crtc *crtc)
        if (WARN_ON(!format))
                return;
 
-       if (format->fourcc == DRM_FORMAT_RGB888)
-               arc_pgu_write(arcpgu, ARCPGU_REG_CTRL,
-                             arc_pgu_read(arcpgu, ARCPGU_REG_CTRL) |
-                                          ARCPGU_MODE_RGB888_MASK);
-
+       reg_ctrl = arc_pgu_read(arcpgu, ARCPGU_REG_CTRL);
+       if (format->fourcc == DRM_FORMAT_RGB565)
+               reg_ctrl &= ~ARCPGU_MODE_RGB888_MASK;
+       else
+               reg_ctrl |= ARCPGU_MODE_RGB888_MASK;
+       arc_pgu_write(arcpgu, ARCPGU_REG_CTRL, reg_ctrl);
 }
 
 static const struct drm_crtc_funcs arc_pgu_crtc_funcs = {