Re: [PATCH v4 2/3] serial: 8250: Add Loongson uart driver support

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

Hi Binbin,

kernel test robot noticed the following build errors:

[auto build test ERROR on b601e1f41edd4667062aa7cccb4e5199814979a3]

url:    https://github.com/intel-lab-lkp/linux/commits/Binbin-Zhou/dt-bindings-serial-Add-Loongson-UART-controller/20250909-201640
base:   b601e1f41edd4667062aa7cccb4e5199814979a3
patch link:    https://lore.kernel.org/r/91ae8cd4f903ac452e337e4662bbabf8a412b061.1757318368.git.zhoubinbin%40loongson.cn
patch subject: [PATCH v4 2/3] serial: 8250: Add Loongson uart driver support
config: m68k-allmodconfig (https://download.01.org/0day-ci/archive/20250910/202509101843.2PXpHVfr-lkp@intel.com/config)
compiler: m68k-linux-gcc (GCC) 15.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250910/202509101843.2PXpHVfr-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/202509101843.2PXpHVfr-lkp@intel.com/

All errors (new ones prefixed by >>):

   drivers/tty/serial/8250/8250_loongson.c: In function 'loongson_uart_probe':
>> drivers/tty/serial/8250/8250_loongson.c:102:9: error: implicit declaration of function 'device_property_read_u32' [-Wimplicit-function-declaration]
     102 |         device_property_read_u32(dev, "clock-frequency", &uart.port.uartclk);
         |         ^~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/tty/serial/8250/8250_loongson.c:117:28: error: implicit declaration of function 'device_get_match_data'; did you mean 'device_match_any'? [-Wimplicit-function-declaration]
     117 |         flags = (uintptr_t)device_get_match_data(dev);
         |                            ^~~~~~~~~~~~~~~~~~~~~
         |                            device_match_any
   drivers/tty/serial/8250/8250_loongson.c: At top level:
>> drivers/tty/serial/8250/8250_loongson.c:179:34: error: array type has incomplete element type 'struct of_device_id'
     179 | static const struct of_device_id loongson_uart_of_ids[] = {
         |                                  ^~~~~~~~~~~~~~~~~~~~


vim +/device_property_read_u32 +102 drivers/tty/serial/8250/8250_loongson.c

    80	
    81	static int loongson_uart_probe(struct platform_device *pdev)
    82	{
    83		struct device *dev = &pdev->dev;
    84		struct uart_8250_port uart = {};
    85		struct loongson_uart_data *ddata;
    86		struct resource *res;
    87		unsigned int flags;
    88		int ret;
    89	
    90		ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
    91		if (!ddata)
    92			return -ENOMEM;
    93	
    94		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    95		if (!res)
    96			return -ENODEV;
    97	
    98		uart.port.irq = platform_get_irq(pdev, 0);
    99		if (uart.port.irq < 0)
   100			return -EINVAL;
   101	
 > 102		device_property_read_u32(dev, "clock-frequency", &uart.port.uartclk);
   103	
   104		spin_lock_init(&uart.port.lock);
   105		uart.port.flags = UPF_SHARE_IRQ | UPF_FIXED_PORT | UPF_FIXED_TYPE | UPF_IOREMAP;
   106		uart.port.iotype = UPIO_MEM;
   107		uart.port.regshift = 0;
   108		uart.port.dev = dev;
   109		uart.port.type = PORT_LOONGSON;
   110		uart.port.private_data = ddata;
   111	
   112		uart.port.mapbase = res->start;
   113		uart.port.mapsize = resource_size(res);
   114		uart.port.serial_in = loongson_serial_in;
   115		uart.port.serial_out = loongson_serial_out;
   116	
 > 117		flags = (uintptr_t)device_get_match_data(dev);
   118	
   119		if (flags & LOONGSON_UART_HAS_FRAC) {
   120			uart.port.get_divisor = loongson_frac_get_divisor;
   121			uart.port.set_divisor = loongson_frac_set_divisor;
   122		}
   123	
   124		if (flags & LOONGSON_UART_QUIRK_MCR)
   125			ddata->mcr_invert |= (UART_MCR_RTS | UART_MCR_DTR);
   126	
   127		if (flags & LOONGSON_UART_QUIRK_MSR)
   128			ddata->msr_invert |= (UART_MSR_CTS | UART_MSR_DSR);
   129	
   130		ddata->rst = devm_reset_control_get_optional_shared(dev, NULL);
   131		if (IS_ERR(ddata->rst))
   132			return PTR_ERR(ddata->rst);
   133	
   134		ret = reset_control_deassert(ddata->rst);
   135		if (ret)
   136			return ret;
   137	
   138		ret = serial8250_register_8250_port(&uart);
   139		if (ret < 0) {
   140			reset_control_assert(ddata->rst);
   141			return ret;
   142		}
   143	
   144		ddata->line = ret;
   145		platform_set_drvdata(pdev, ddata);
   146	
   147		return 0;
   148	}
   149	
   150	static void loongson_uart_remove(struct platform_device *pdev)
   151	{
   152		struct loongson_uart_data *ddata = platform_get_drvdata(pdev);
   153	
   154		serial8250_unregister_port(ddata->line);
   155		reset_control_assert(ddata->rst);
   156	}
   157	
   158	static int loongson_uart_suspend(struct device *dev)
   159	{
   160		struct loongson_uart_data *ddata = dev_get_drvdata(dev);
   161	
   162		serial8250_suspend_port(ddata->line);
   163	
   164		return 0;
   165	}
   166	
   167	static int loongson_uart_resume(struct device *dev)
   168	{
   169		struct loongson_uart_data *data = dev_get_drvdata(dev);
   170	
   171		serial8250_resume_port(data->line);
   172	
   173		return 0;
   174	}
   175	
   176	static DEFINE_SIMPLE_DEV_PM_OPS(loongson_uart_pm_ops, loongson_uart_suspend,
   177					loongson_uart_resume);
   178	
 > 179	static const struct of_device_id loongson_uart_of_ids[] = {
   180		{ .compatible = "loongson,ls2k0500-uart", .data = (void *)LS2K0500_UART_FLAG },
   181		{ .compatible = "loongson,ls2k1500-uart", .data = (void *)LS2K1500_UART_FLAG },
   182		{ /* sentinel */ },
   183	};
   184	MODULE_DEVICE_TABLE(of, loongson_uart_of_ids);
   185	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki