drm/fb-helper: Don't clobber the display palette when fbdev isn't bound
Perform the drm_fb_helper_is_bound() check to avoid clobbering the
display palette of some other KMS client.
While at it, fix up the locking by grabbing all modeset locks for the
duration of the fb_setcmap operation.
v2: Make a note of the locking changes in the commit message
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@gmail.com>
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 7821975..dff2058 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -640,12 +640,19 @@
int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
{
struct drm_fb_helper *fb_helper = info->par;
+ struct drm_device *dev = fb_helper->dev;
struct drm_crtc_helper_funcs *crtc_funcs;
u16 *red, *green, *blue, *transp;
struct drm_crtc *crtc;
int i, j, rc = 0;
int start;
+ drm_modeset_lock_all(dev);
+ if (!drm_fb_helper_is_bound(fb_helper)) {
+ drm_modeset_unlock_all(dev);
+ return -EBUSY;
+ }
+
for (i = 0; i < fb_helper->crtc_count; i++) {
crtc = fb_helper->crtc_info[i].mode_set.crtc;
crtc_funcs = crtc->helper_private;
@@ -668,10 +675,12 @@
rc = setcolreg(crtc, hred, hgreen, hblue, start++, info);
if (rc)
- return rc;
+ goto out;
}
crtc_funcs->load_lut(crtc);
}
+ out:
+ drm_modeset_unlock_all(dev);
return rc;
}
EXPORT_SYMBOL(drm_fb_helper_setcmap);