Re: [PATCH 2/3] drm/i915/bios: Add function to check if edp data override is needed

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

Hi Suraj,

kernel test robot noticed the following build warnings:

[auto build test WARNING on drm-intel/for-linux-next]
[also build test WARNING on linus/master v6.16-rc7 next-20250725]
[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/Suraj-Kandpal/drm-i915-vbt-Add-eDP-Data-Overrride-field-in-VBT/20250725-141824
base:   git://anongit.freedesktop.org/drm-intel for-linux-next
patch link:    https://lore.kernel.org/r/20250725061548.2704697-3-suraj.kandpal%40intel.com
patch subject: [PATCH 2/3] drm/i915/bios: Add function to check if edp data override is needed
config: i386-buildonly-randconfig-006-20250725 (https://download.01.org/0day-ci/archive/20250726/202507261913.LoCL2yuM-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250726/202507261913.LoCL2yuM-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/202507261913.LoCL2yuM-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/i915/display/intel_bios.c:2524:2: warning: variable 'val' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized]
    2524 |         default:
         |         ^~~~~~~
   drivers/gpu/drm/i915/display/intel_bios.c:2528:34: note: uninitialized use occurs here
    2528 |         return edp_data_override_mask & val;
         |                                         ^~~
   drivers/gpu/drm/i915/display/intel_bios.c:2485:9: note: initialize the variable 'val' to silence this warning
    2485 |         u32 val;
         |                ^
         |                 = 0
   1 warning generated.


vim +/val +2524 drivers/gpu/drm/i915/display/intel_bios.c

  2482	
  2483	static bool parse_bdb_263_edp_data_override(const u32 edp_data_override_mask, int rate)
  2484	{
  2485		u32 val;
  2486	
  2487		switch (rate) {
  2488		case 2000000:
  2489			val = BDB_263_VBT_EDP_LINK_RATE_20;
  2490			break;
  2491		case 1350000:
  2492			val = BDB_263_VBT_EDP_LINK_RATE_13_5;
  2493			break;
  2494		case 1000000:
  2495			val = BDB_263_VBT_EDP_LINK_RATE_10;
  2496			break;
  2497		case 810000:
  2498			val = BDB_263_VBT_EDP_LINK_RATE_8_1;
  2499			break;
  2500		case 675000:
  2501			val = BDB_263_VBT_EDP_LINK_RATE_6_75;
  2502			break;
  2503		case 540000:
  2504			val = BDB_263_VBT_EDP_LINK_RATE_5_4;
  2505			break;
  2506		case 432000:
  2507			val = BDB_263_VBT_EDP_LINK_RATE_4_32;
  2508			break;
  2509		case 324000:
  2510			val = BDB_263_VBT_EDP_LINK_RATE_3_24;
  2511			break;
  2512		case 270000:
  2513			val = BDB_263_VBT_EDP_LINK_RATE_2_7;
  2514			break;
  2515		case 243000:
  2516			val = BDB_263_VBT_EDP_LINK_RATE_2_43;
  2517			break;
  2518		case 216000:
  2519			val = BDB_263_VBT_EDP_LINK_RATE_2_16;
  2520			break;
  2521		case 162000:
  2522			val = BDB_263_VBT_EDP_LINK_RATE_1_62;
  2523			break;
> 2524		default:
  2525			break;
  2526		}
  2527	
  2528		return edp_data_override_mask & val;
  2529	}
  2530	

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