Hi Rajeev,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on drm-intel/for-linux-next]
[also build test ERROR on drm-tip/drm-tip drm-exynos/exynos-drm-next tegra-drm/drm/tegra/for-next linus/master v5.13-rc3 next-20210528]
[cannot apply to drm/drm-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Rajeev-Nandan/drm-Support-basic-DPCD-backlight-in-panel-simple-and-add-a-new-panel-ATNA33XC20/20210530-235810
base:   git://anongit.freedesktop.org/drm-intel for-linux-next
config: arm64-randconfig-r005-20210530 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project bc6799f2f79f0ae87e9f1ebf9d25ba799fbd25a9)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # https://github.com/0day-ci/linux/commit/1cf1b3f6b1f766d4e932422d1cdec19354acdcc3
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Rajeev-Nandan/drm-Support-basic-DPCD-backlight-in-panel-simple-and-add-a-new-panel-ATNA33XC20/20210530-235810
        git checkout 1cf1b3f6b1f766d4e932422d1cdec19354acdcc3
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

>> drivers/gpu/drm/drm_panel.c:39:32: error: field has incomplete type 'struct drm_edp_backlight_info'
           struct drm_edp_backlight_info info;
                                         ^
   drivers/gpu/drm/drm_panel.c:39:9: note: forward declaration of 'struct drm_edp_backlight_info'
           struct drm_edp_backlight_info info;
                  ^
>> drivers/gpu/drm/drm_panel.c:362:4: error: implicit declaration of function 'drm_edp_backlight_enable' [-Werror,-Wimplicit-function-declaration]
                           drm_edp_backlight_enable(bl->aux, &bl->info, brightness);
                           ^
   drivers/gpu/drm/drm_panel.c:362:4: note: did you mean 'backlight_enable'?
   include/linux/backlight.h:363:19: note: 'backlight_enable' declared here
   static inline int backlight_enable(struct backlight_device *bd)
                     ^
>> drivers/gpu/drm/drm_panel.c:366:9: error: implicit declaration of function 'drm_edp_backlight_set_level' [-Werror,-Wimplicit-function-declaration]
                   ret = drm_edp_backlight_set_level(bl->aux, &bl->info, brightness);
                         ^
>> drivers/gpu/drm/drm_panel.c:369:4: error: implicit declaration of function 'drm_edp_backlight_disable' [-Werror,-Wimplicit-function-declaration]
                           drm_edp_backlight_disable(bl->aux, &bl->info);
                           ^
   drivers/gpu/drm/drm_panel.c:369:4: note: did you mean 'backlight_disable'?
   include/linux/backlight.h:379:19: note: 'backlight_disable' declared here
   static inline int backlight_disable(struct backlight_device *bd)
                     ^
>> drivers/gpu/drm/drm_panel.c:428:7: error: implicit declaration of function 'drm_edp_backlight_supported' [-Werror,-Wimplicit-function-declaration]
           if (!drm_edp_backlight_supported(edp_dpcd)) {
                ^
>> drivers/gpu/drm/drm_panel.c:433:8: error: implicit declaration of function 'drm_edp_backlight_init' [-Werror,-Wimplicit-function-declaration]
           ret = drm_edp_backlight_init(aux, &bl->info, 0, edp_dpcd,
                 ^
   6 errors generated.


vim +39 drivers/gpu/drm/drm_panel.c

    35	
    36	struct dp_aux_backlight {
    37		struct backlight_device *base;
    38		struct drm_dp_aux *aux;
  > 39		struct drm_edp_backlight_info info;
    40		bool enabled;
    41	};
    42	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org