On Sat, 2026-10-24 at 19:59 +0800, kernel test robot wrote:
> Hi ChunAn,
> 
> kernel test robot noticed the following build errors:
> 
> [auto build test ERROR on driver-core/driver-core-testing]
> [also build test ERROR on driver-core/driver-core-next driver-core/driver-core-linus linus/master v7.3 next-20261022]
> [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/ChunAn-Wu/platform-x86-dell-uart-backlight-Bind-through-normal-serdev-matching/20261024-102929
> base:   driver-core/driver-core-testing
> patch link:    https://lore.kernel.org/r/20261024022930.2704030-3-an.wu%40canonical.com
> patch subject: [PATCH v4] platform/x86: dell-uart-backlight: Bind through normal serdev matching
> config: i386-randconfig-1007-20261024 (https://download.01.org/0day-ci/archive/20261024/202610241920.GJiRENj2-lkp@intel.com/config)
> compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20261024/202610241920.GJiRENj2-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/202610241920.GJiRENj2-lkp@intel.com/
> 
> All error/warnings (new ones prefixed by >>):
> 
> > > drivers/platform/x86/dell/dell-uart-backlight.c:328:38: error: array type has incomplete element type 'struct serdev_device_id'
>      328 | static const struct serdev_device_id dell_uart_bl_serdev_id[] = {
>          |                                      ^~~~~~~~~~~~~~~~~~~~~~
> > > drivers/platform/x86/dell/dell-uart-backlight.c:338:10: error: 'struct serdev_device_driver' has no member named 'id_table'
>      338 |         .id_table = dell_uart_bl_serdev_id,
>          |          ^~~~~~~~
>    drivers/platform/x86/dell/dell-uart-backlight.c: In function 'dell_uart_bl_pdev_probe':
> > > drivers/platform/x86/dell/dell-uart-backlight.c:363:15: error: too many arguments to function 'serdev_device_add'
>      363 |         ret = serdev_device_add(serdev, KBUILD_MODNAME);
>          |               ^~~~~~~~~~~~~~~~~
>    In file included from drivers/platform/x86/dell/dell-uart-backlight.c:19:
>    include/linux/serdev.h:161:5: note: declared here
>      161 | int serdev_device_add(struct serdev_device *);
>          |     ^~~~~~~~~~~~~~~~~
>    drivers/platform/x86/dell/dell-uart-backlight.c: At top level:
> > > drivers/platform/x86/dell/dell-uart-backlight.c:328:38: warning: 'dell_uart_bl_serdev_id' defined but not used [-Wunused-variable]
>      328 | static const struct serdev_device_id dell_uart_bl_serdev_id[] = {
>          |                                      ^~~~~~~~~~~~~~~~~~~~~~
> 
> 
> vim +328 drivers/platform/x86/dell/dell-uart-backlight.c
> 
>    327	
>  > 328	static const struct serdev_device_id dell_uart_bl_serdev_id[] = {
>    329		{ KBUILD_MODNAME },
>    330		{ }
>    331	};
>    332	
>    333	static struct serdev_device_driver dell_uart_bl_serdev_driver = {
>    334		.probe = dell_uart_bl_serdev_probe,
>    335		.driver = {
>    336			.name = KBUILD_MODNAME,
>    337		},
>  > 338		.id_table = dell_uart_bl_serdev_id,
>    339	};
>    340	
>    341	static int dell_uart_bl_pdev_probe(struct platform_device *pdev)
>    342	{
>    343		enum acpi_backlight_type bl_type;
>    344		struct serdev_device *serdev;
>    345		struct device *ctrl_dev;
>    346		int ret;
>    347	
>    348		bl_type = acpi_video_get_backlight_type();
>    349		if (bl_type != acpi_backlight_dell_uart) {
>    350			dev_dbg(&pdev->dev, "Not loading (ACPI backlight type = %d)\n", bl_type);
>    351			return -ENODEV;
>    352		}
>    353	
>    354		ctrl_dev = get_serdev_controller("DELL0501", NULL, 0, "serial0");
>    355		if (IS_ERR(ctrl_dev))
>    356			return PTR_ERR(ctrl_dev);
>    357	
>    358		serdev = serdev_device_alloc(to_serdev_controller(ctrl_dev));
>    359		put_device(ctrl_dev);
>    360		if (!serdev)
>    361			return -ENOMEM;
>    362	
>  > 363		ret = serdev_device_add(serdev, KBUILD_MODNAME);
>    364		if (ret) {
>    365			dev_err(&pdev->dev, "error %d adding serdev\n", ret);
>    366			serdev_device_put(serdev);
>    367			return ret;
>    368		}
>    369	
>    370		ret = serdev_device_driver_register(&dell_uart_bl_serdev_driver);
>    371		if (ret)
>    372			goto err_remove_serdev;
>    373	
>    374		/* So that dell_uart_bl_pdev_remove() can remove the serdev */
>    375		platform_set_drvdata(pdev, serdev);
>    376		return 0;
>    377	
>    378	err_remove_serdev:
>    379		serdev_device_remove(serdev);
>    380		return ret;
>    381	}
>    382	
> 
> --
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki

Because of the missing "2/3" in the subject line it likely has applied
it as first patch. I assume that was by mistake, given you also resent
the same patch again with the correct subject line.

Anyway, this report should be meaningless.

Thanks
- Markus Probst