Hi Andreas,

[FYI, it's a private test report for your RFC patch.]
[auto build test WARNING on drm/drm-next]
[also build test WARNING on robh/for-next v5.17-rc2 next-20220204]
[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/Andreas-Kemnade/drm-EPDC-driver-for-i-MX6/20220206-162244
base:   git://anongit.freedesktop.org/drm/drm drm-next
config: ia64-allmodconfig (https://download.01.org/0day-ci/archive/20220206/202202061800.LKz4rHPK-lkp(a)intel.com/config)
compiler: ia64-linux-gcc (GCC) 11.2.0
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
        # https://github.com/0day-ci/linux/commit/e5b9ffe09a0668f81e87931aee2281dc7340d40b
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Andreas-Kemnade/drm-EPDC-driver-for-i-MX6/20220206-162244
        git checkout e5b9ffe09a0668f81e87931aee2281dc7340d40b
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=ia64 SHELL=/bin/bash drivers/gpu/drm/mxc-epdc/

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

All warnings (new ones prefixed by >>):

   drivers/gpu/drm/mxc-epdc/epdc_hw.c: In function 'mxc_epdc_powerup':
>> drivers/gpu/drm/mxc-epdc/epdc_hw.c:49:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
      49 |         if (IS_ERR((void *)ret)) {
         |                    ^
   drivers/gpu/drm/mxc-epdc/epdc_hw.c:69:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
      69 |         if (IS_ERR((void *)ret)) {
         |                    ^
   drivers/gpu/drm/mxc-epdc/epdc_hw.c:78:20: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
      78 |         if (IS_ERR((void *)ret)) {
         |                    ^
   drivers/gpu/drm/mxc-epdc/epdc_hw.c: At top level:
   drivers/gpu/drm/mxc-epdc/epdc_hw.c:174:6: warning: no previous prototype for 'epdc_init_settings' [-Wmissing-prototypes]
     174 | void epdc_init_settings(struct mxc_epdc *priv, struct drm_display_mode *m)
         |      ^~~~~~~~~~~~~~~~~~


vim +49 drivers/gpu/drm/mxc-epdc/epdc_hw.c

    24	
    25	void mxc_epdc_powerup(struct mxc_epdc *priv)
    26	{
    27		int ret = 0;
    28	
    29		mutex_lock(&priv->power_mutex);
    30	
    31		/*
    32		 * If power down request is pending, clear
    33		 * powering_down to cancel the request.
    34		 */
    35		if (priv->powering_down)
    36			priv->powering_down = false;
    37	
    38		if (priv->powered) {
    39			mutex_unlock(&priv->power_mutex);
    40			return;
    41		}
    42	
    43		dev_dbg(priv->drm.dev, "EPDC Powerup\n");
    44	
    45		priv->updates_active = true;
    46	
    47		/* Enable the v3p3 regulator */
    48		ret = regulator_enable(priv->v3p3_regulator);
  > 49		if (IS_ERR((void *)ret)) {
    50			dev_err(priv->drm.dev,
    51				"Unable to enable V3P3 regulator. err = 0x%x\n",
    52				ret);
    53			mutex_unlock(&priv->power_mutex);
    54			return;
    55		}
    56	
    57		usleep_range(1000, 2000);
    58	
    59		pm_runtime_get_sync(priv->drm.dev);
    60	
    61		/* Enable clocks to EPDC */
    62		clk_prepare_enable(priv->epdc_clk_axi);
    63		clk_prepare_enable(priv->epdc_clk_pix);
    64	
    65		epdc_write(priv, EPDC_CTRL_CLEAR, EPDC_CTRL_CLKGATE);
    66	
    67		/* Enable power to the EPD panel */
    68		ret = regulator_enable(priv->display_regulator);
    69		if (IS_ERR((void *)ret)) {
    70			dev_err(priv->drm.dev,
    71				"Unable to enable DISPLAY regulator. err = 0x%x\n",
    72				ret);
    73			mutex_unlock(&priv->power_mutex);
    74			return;
    75		}
    76	
    77		ret = regulator_enable(priv->vcom_regulator);
    78		if (IS_ERR((void *)ret)) {
    79			dev_err(priv->drm.dev,
    80				"Unable to enable VCOM regulator. err = 0x%x\n",
    81				ret);
    82			mutex_unlock(&priv->power_mutex);
    83			return;
    84		}
    85	
    86		priv->powered = true;
    87	
    88		mutex_unlock(&priv->power_mutex);
    89	}
    90	

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