Re: [PATCH 3/3] drm/nuvoton: add MA35D1 display controller driver

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

Hi Joey,

kernel test robot noticed the following build errors:

[auto build test ERROR on drm-misc/drm-misc-next]
[also build test ERROR on drm/drm-next]
[cannot apply to robh/for-next linus/master v6.19-rc7 next-20260126]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Joey-Lu/dt-bindings-display-nuvoton-add-MA35D1-DCU-binding/20260126-170258
base:   https://gitlab.freedesktop.org/drm/misc/kernel.git drm-misc-next
patch link:    https://lore.kernel.org/r/20260126085727.2568958-4-a0987203069%40gmail.com
patch subject: [PATCH 3/3] drm/nuvoton: add MA35D1 display controller driver
config: hexagon-allmodconfig (https://download.01.org/0day-ci/archive/20260127/202601272315.09SFioVt-lkp@intel.com/config)
compiler: clang version 17.0.6 (https://github.com/llvm/llvm-project 6009708b4367171ccdbf4b5905cb6a803753fe18)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260127/202601272315.09SFioVt-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/202601272315.09SFioVt-lkp@intel.com/

All error/warnings (new ones prefixed by >>):

>> drivers/gpu/drm/nuvoton/ma35_plane.c:177:10: error: call to undeclared function 'FIELD_PREP'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     177 |                 *reg = MA35_BLEND_MODE_SRC;
         |                        ^
   drivers/gpu/drm/nuvoton/ma35_plane.h:141:2: note: expanded from macro 'MA35_BLEND_MODE_SRC'
     141 |         FIELD_PREP(MA35_SRC_BLENDING_MODE, MA35_ALPHA_BLEND_ONE)
         |         ^
   drivers/gpu/drm/nuvoton/ma35_plane.c:337:8: error: call to undeclared function 'FIELD_PREP'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     337 |         reg = FIELD_PREP(MA35_OVERLAY_POSITION_X_MASK, x) |
         |               ^
   drivers/gpu/drm/nuvoton/ma35_plane.c:360:9: error: call to undeclared function 'FIELD_PREP'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     360 |                 reg = FIELD_PREP(MA35_PRIMARY_FORMAT_MASK, format) |
         |                       ^
   drivers/gpu/drm/nuvoton/ma35_plane.c:384:9: error: call to undeclared function 'FIELD_PREP'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     384 |                 reg = FIELD_PREP(MA35_OVERLAY_FORMAT_MASK, format) |
         |                       ^
   drivers/gpu/drm/nuvoton/ma35_plane.c:441:8: error: call to undeclared function 'FIELD_PREP'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     441 |         reg = FIELD_PREP(MA35_CURSOR_X_MASK, x) |
         |               ^
   drivers/gpu/drm/nuvoton/ma35_plane.c:483:4: error: call to undeclared function 'FIELD_PREP'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     483 |                         FIELD_PREP(MA35_CURSOR_HOTSPOT_X_MASK, new_state->hotspot_x) |
         |                         ^
   drivers/gpu/drm/nuvoton/ma35_plane.c:537:4: error: call to undeclared function 'FIELD_PREP'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     537 |                         FIELD_PREP(MA35_CURSOR_HOTSPOT_X_MASK, new_state->hotspot_x) |
         |                         ^
   7 errors generated.
--
>> drivers/gpu/drm/nuvoton/ma35_crtc.c:97:8: error: call to undeclared function 'FIELD_PREP'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
      97 |         reg = FIELD_PREP(MA35_DISPLAY_TOTAL_MASK, mode->htotal) |
         |               ^
>> drivers/gpu/drm/nuvoton/ma35_crtc.c:228:10: error: call to undeclared function 'FIELD_GET'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     228 |         *hpos = FIELD_GET(MA35_DISPLAY_CURRENT_X, reg);
         |                 ^
   drivers/gpu/drm/nuvoton/ma35_crtc.c:284:9: error: call to undeclared function 'FIELD_PREP'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
     284 |                 reg = FIELD_PREP(MA35_GAMMA_RED_MASK, r[i]) |
         |                       ^
   3 errors generated.
--
>> drivers/gpu/drm/nuvoton/ma35_interface.c:150:6: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
     150 |         if (!interface) {
         |             ^~~~~~~~~~
   drivers/gpu/drm/nuvoton/ma35_interface.c:191:9: note: uninitialized use occurs here
     191 |         return ret;
         |                ^~~
   drivers/gpu/drm/nuvoton/ma35_interface.c:150:2: note: remove the 'if' if its condition is always false
     150 |         if (!interface) {
         |         ^~~~~~~~~~~~~~~~~
     151 |                 drm_err(drm_dev, "Failed to initialize encoder\n");
         |                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     152 |                 goto error_early;
         |                 ~~~~~~~~~~~~~~~~~
     153 |         }
         |         ~
   drivers/gpu/drm/nuvoton/ma35_interface.c:145:9: note: initialize the variable 'ret' to silence this warning
     145 |         int ret;
         |                ^
         |                 = 0
   1 warning generated.


vim +/FIELD_PREP +177 drivers/gpu/drm/nuvoton/ma35_plane.c

   167	
   168	static int ma35_layer_blend_mode_select(u32 mode, u32 *reg)
   169	{
   170		u32 ret = 0;
   171	
   172		switch (mode) {
   173		case MA35_ALPHA_CLEAR:
   174			*reg = MA35_BLEND_MODE_CLEAR;
   175			break;
   176		case MA35_ALPHA_SRC:
 > 177			*reg = MA35_BLEND_MODE_SRC;
   178			break;
   179		case MA35_ALPHA_DST:
   180			*reg = MA35_BLEND_MODE_DST;
   181			break;
   182		case MA35_ALPHA_SRC_OVER:
   183			*reg = MA35_BLEND_MODE_SRC_OVER;
   184			break;
   185		case MA35_ALPHA_DST_OVER:
   186			*reg = MA35_BLEND_MODE_DST_OVER;
   187			break;
   188		case MA35_ALPHA_SRC_IN:
   189			*reg = MA35_BLEND_MODE_SRC_IN;
   190			break;
   191		case MA35_ALPHA_DST_IN:
   192			*reg = MA35_BLEND_MODE_DST_IN;
   193			break;
   194		case MA35_ALPHA_SRC_OUT:
   195			*reg = MA35_BLEND_MODE_SRC_OUT;
   196			break;
   197		case MA35_ALPHA_DST_OUT:
   198			*reg = MA35_BLEND_MODE_DST_OUT;
   199			break;
   200		case MA35_ALPHA_SRC_ATOP:
   201			*reg = MA35_BLEND_MODE_SRC_ATOP;
   202			break;
   203		case MA35_ALPHA_DST_ATOP:
   204			*reg = MA35_BLEND_MODE_DST_ATOP;
   205			break;
   206		case MA35_ALPHA_XOR:
   207			*reg = MA35_BLEND_MODE_XOR;
   208			break;
   209		default:
   210			ret = -EINVAL;
   211		}
   212	
   213		return ret;
   214	}
   215	

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