From: Ville Syrjälä ville.syrjala@linux.intel.com
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 --- drivers/gpu/drm/drm_fb_helper.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index b78cbe7..1b6ca23 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -626,12 +626,19 @@ static int setcolreg(struct drm_crtc *crtc, u16 red, u16 green, 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; @@ -654,10 +661,12 @@ int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
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);