[PATCH v3 3/3] drm/kms: allocate framebuffer cmap

[Clemens Ladisch <clemens@ladisch.de>]

Without an allocated colormap, FBIOGETCMAP fails.  This would make
programs restore an all-black colormap ("links -g") or fail to work
altogether ("mplayer -vo fbdev2").

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
---
v3: bugfix by James Simmons

 drivers/gpu/drm/drm_fb_helper.c |   7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- linux-2.6/drivers/gpu/drm/drm_fb_helper.c
+++ linux-2.6/drivers/gpu/drm/drm_fb_helper.c
@@ -905,8 +905,13 @@ int drm_fb_helper_single_fb_probe(struct
 
 	if (new_fb) {
 		info->var.pixclock = 0;
-		if (register_framebuffer(info) < 0)
+		ret = fb_alloc_cmap(&info->cmap, crtc->gamma_size, 0);
+		if (ret)
+			return ret;
+		if (register_framebuffer(info) < 0) {
+			fb_dealloc_cmap(&info->cmap);
 			return -EINVAL;
+		}
 	} else {
 		drm_fb_helper_set_par(info);
 	}
@@ -936,6 +941,7 @@ void drm_fb_helper_free(struct drm_fb_he
 		unregister_sysrq_key('v', &sysrq_drm_fb_helper_restore_op);
 	}
 	drm_fb_helper_crtc_free(helper);
+	fb_dealloc_cmap(&helper->fb->fbdev->cmap);
 }
 EXPORT_SYMBOL(drm_fb_helper_free);