Re: [PATCH v4] drm/trigger5: Add MCT Trigger 5 USB display driver

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

Hi Ho,

kernel test robot noticed the following build warnings:

[auto build test WARNING on 73df79cceb8c01f311055a61794e229dc81546cb]

url:    https://github.com/intel-lab-lkp/linux/commits/Ho-Jie-Feng/drm-trigger5-Add-MCT-Trigger-5-USB-display-driver/20261012-211537
base:   73df79cceb8c01f311055a61794e229dc81546cb
patch link:    https://lore.kernel.org/r/20261012131539.67790-1-hjf3108%40gmail.com
patch subject: [PATCH v4] drm/trigger5: Add MCT Trigger 5 USB display driver
config: powerpc-randconfig-1000-20261014 (https://download.01.org/0day-ci/archive/20261014/202610141333.eWqPGRTA-lkp@intel.com/config)
compiler: clang version 19.1.7 (https://github.com/llvm/llvm-project cd708029e0b2869e80abe31ddb175f7c35361f90)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20261014/202610141333.eWqPGRTA-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/202610141333.eWqPGRTA-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/tiny/trigger5.c:550:19: warning: result of comparison of constant 65536 with expression of type 'const u16' (aka 'const unsigned short') is always false [-Wtautological-constant-out-of-range-compare]
     550 |             mode->htotal > U16_MAX + 1)
         |             ~~~~~~~~~~~~ ^ ~~~~~~~~~~~
   drivers/gpu/drm/tiny/trigger5.c:555:19: warning: result of comparison of constant 65536 with expression of type 'const u16' (aka 'const unsigned short') is always false [-Wtautological-constant-out-of-range-compare]
     555 |             mode->vtotal > U16_MAX + 1)
         |             ~~~~~~~~~~~~ ^ ~~~~~~~~~~~
   2 warnings generated.


vim +550 drivers/gpu/drm/tiny/trigger5.c

   540	
   541	static enum drm_mode_status
   542	trigger5_crtc_mode_valid(struct drm_crtc *crtc,
   543				 const struct drm_display_mode *mode)
   544	{
   545		struct trigger5_pll pll;
   546		u64 err, ppm;
   547	
   548		if (mode->hsync_end <= mode->hsync_start ||
   549		    mode->htotal <= mode->hsync_end ||
 > 550		    mode->htotal > U16_MAX + 1)
   551			return MODE_H_ILLEGAL;
   552	
   553		if (mode->vsync_end <= mode->vsync_start ||
   554		    mode->vtotal <= mode->vsync_end ||
   555		    mode->vtotal > U16_MAX + 1)
   556			return MODE_V_ILLEGAL;
   557	
   558		if (trigger5_mode_buf_len(mode) > TRIGGER5_TRANSFER_BUF_SIZE)
   559			return MODE_MEM;
   560	
   561		err = trigger5_calculate_pll(&pll, mode->clock);
   562		ppm = div64_u64(err * 1000, mode->clock);
   563		if (ppm > 10000)
   564			return MODE_CLOCK_RANGE;
   565	
   566		return MODE_OK;
   567	}
   568	

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