linux platform driver without dts

linux3.0 spi-s3c64xx.c
最近写一个spi dma的程序，不得已要先改在linux3.0上面
有dts支持的情况下一般是dts 的devnode 跟platform driver的of_match_table 的compatible 
属性match然后probe
3.0的时候还不支持dts，那用来match的属性各自在何处定义的呢

static int platform_match(struct device *dev, struct device_driver *drv)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct platform_driver *pdrv = to_platform_driver(drv);

	/* Attempt an OF style match first */
	if (of_driver_match_device(dev, drv))
		return 1;
//对比device dts node和driver of_match_table de compatibel属性
	/* Then try to match against the id table */
	if (pdrv->id_table)
		return platform_match_id(pdrv->id_table, pdev) != NULL;
//对比driver的id_table与device的name是否匹配
	/* fall-back to driver name match */
	return (strcmp(pdev->name, drv->name) == 0);
//直接对比device的name和driver的name
}


platform_driver结构体定义了driver的name
static struct platform_driver s3c64xx_spi_driver = {
	.driver = {
		.name	= "s3c64xx-spi",
		.owner = THIS_MODULE,
	},

没有match table 也没有id_table 也没有明显的看到有device name,这时候driver和device是如何match的呢

linux3.18 4.9 版本支持dts，platform device加入的方法是通过of_platform_populate根据dts的dev node 添加进platform device list，如果没有dts的话是在哪个阶段把platform device 添加进来的呢，mach-init！

在mach-s3c64xx.c中找到了spi的platform device的定义


struct platform_device s3c64xx_device_spi0 = {
	.name		  = "s3c64xx-spi",
	.id		  = 0,
	.num_resources	  = ARRAY_SIZE(s3c64xx_spi0_resource),
	.resource	  = s3c64xx_spi0_resource,
	.dev = {
		.dma_mask		= &spi_dmamask,
		.coherent_dma_mask	= DMA_BIT_MASK(32),
		.platform_data = &s3c64xx_spi0_pdata,
	},
};
EXPORT_SYMBOL(s3c64xx_device_spi0);


static struct platform_device *smdk6410_devices[] __initdata = {
    &s3c64xx_device_spi0,
}

static void __init smdk6410_machine_init(void)
{

	s3c_ide_set_platdata(&smdk6410_ide_pdata);

	platform_add_devices(smdk6410_devices, ARRAY_SIZE(smdk6410_devices));
}

在machine_init里建立platform device，spi init的时候注册了driver后probe就会执行

linux platform driver without dts

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