[asahilinux:bits/200-dcp 41/115] drivers/gpu/drm/apple/dcp.c:189:45: warning: variable 'old_state' set but not used

[kernel test robot <lkp@intel.com>]

tree:   https://github.com/AsahiLinux/linux bits/200-dcp
head:   f4266bb9a0d063559ea03f3a46244bb54c167e0c
commit: bd2514bb7f205c34b109c693edfad7853892e33e [41/115] gpu: drm: apple: Add dcp_crtc_atomic_check
config: arm64-allyesconfig (https://download.01.org/0day-ci/archive/20230925/202309250814.ATvf4pce-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230925/202309250814.ATvf4pce-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202309250814.ATvf4pce-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/gpu/drm/apple/dcp.c: In function 'dcp_crtc_atomic_check':
>> drivers/gpu/drm/apple/dcp.c:189:45: warning: variable 'old_state' set but not used [-Wunused-but-set-variable]
     189 |         struct drm_plane_state *new_state, *old_state;
         |                                             ^~~~~~~~~


vim +/old_state +189 drivers/gpu/drm/apple/dcp.c

   184	
   185	int dcp_crtc_atomic_check(struct drm_crtc *crtc, struct drm_atomic_state *state)
   186	{
   187		struct platform_device *pdev = to_apple_crtc(crtc)->dcp;
   188		struct apple_dcp *dcp = platform_get_drvdata(pdev);
 > 189		struct drm_plane_state *new_state, *old_state;
   190		struct drm_plane *plane;
   191		struct drm_crtc_state *crtc_state;
   192		int plane_idx, plane_count = 0;
   193		bool needs_modeset;
   194	
   195		if (dcp->crashed)
   196			return -EINVAL;
   197	
   198		crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
   199	
   200		needs_modeset = drm_atomic_crtc_needs_modeset(crtc_state) || !dcp->valid_mode;
   201		if (!needs_modeset && !dcp->connector->connected) {
   202			dev_err(dcp->dev, "crtc_atomic_check: disconnected but no modeset");
   203			return -EINVAL;
   204		}
   205	
   206		for_each_oldnew_plane_in_state(state, plane, old_state, new_state, plane_idx) {
   207			/* skip planes not for this crtc */
   208			if (new_state->crtc != crtc)
   209				continue;
   210	
   211			plane_count += 1;
   212		}
   213	
   214		if (plane_count > DCP_MAX_PLANES) {
   215			dev_err(dcp->dev, "crtc_atomic_check: Blend supports only 2 layers!");
   216			return -EINVAL;
   217		}
   218	
   219		return 0;
   220	}
   221	EXPORT_SYMBOL_GPL(dcp_crtc_atomic_check);
   222	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki