drm/fb: add more correct 8/16/24/32 bpp fb support.

The previous patches had some unwanted side effects, I've fixed
the lack of 32bpp working, and fixed up 16bpp so it should also work.

this also adds the interface to allow the driver to set a preferred
console depth so for example low memory rn50 can set it to 8bpp.
It also catches 24bpp on cards that can't do it and forces 32bpp.

Tested on r100/r600/i945.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index a840cb1bd36a..893903962e54 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2922,6 +2922,16 @@ void intel_crtc_fb_gamma_set(struct drm_crtc *crtc, u16 red, u16 green,
         intel_crtc->lut_b[regno] = blue >> 8;
 }
 
+void intel_crtc_fb_gamma_get(struct drm_crtc *crtc, u16 *red, u16 *green,
+                             u16 *blue, int regno)
+{
+        struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+
+        *red = intel_crtc->lut_r[regno] << 8;
+        *green = intel_crtc->lut_g[regno] << 8;
+        *blue = intel_crtc->lut_b[regno] << 8;
+}
+
 static void intel_crtc_gamma_set(struct drm_crtc *crtc, u16 *red, u16 *green,
                                  u16 *blue, uint32_t size)
 {