bbb mmc_blk_probe 分析

bbb 的 emmc驱动在drivers\mmc\card\block.c，其mmc_dirver结构体如下，

根据以往平台总线驱动模型的经验来看的话，内核里应该有mmc_devices结构体，并且

其name也为"mmcblk"，这样其probe函数将被调用，但是搜索整个内核文件并没有发现mmc_devices。

现在我们分析一下mmc_blk_probe什么时候被调用。

static struct mmc_driver mmc_driver = {

.drv= {
.name = "mmcblk",
},
.probe = mmc_blk_probe,
.remove = mmc_blk_remove,
.suspend = mmc_blk_suspend,
.resume = mmc_blk_resume,

};

static int __init mmc_blk_init(void) //drivers\mmc\card\block.c
{
res = mmc_register_driver(&mmc_driver); //注册mmc_driver
}

int mmc_register_driver(struct mmc_driver *drv) //drivers\mmc\core\bus.c
{
drv->drv.bus = &mmc_bus_type; //mmc设备是挂载在mmc总线上的
return driver_register(&drv->drv); //注册mmc驱动
}

int driver_register(struct device_driver *drv) //drivers\base\driver.c
{
other = driver_find(drv->name, drv->bus); //在总线上查找是否已经注册过此驱动
if (other) {
put_driver(other);
printk(KERN_ERR "Error: Driver '%s' is already registered, "
"aborting...\n", drv->name);
return -EBUSY;
}

ret = bus_add_driver(drv); //如果没有注册过，则注册此驱动
}

int bus_add_driver(struct device_driver *drv) //drivers\base\bus.c
{
error = driver_attach(drv);
error = driver_create_file(drv, &driver_attr_uevent);
}

//try to bind driver to devices

int driver_attach(struct device_driver *drv) //drivers/base/dd.c
{
return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach);

//__driver_attach的里面device的查找还没搞清楚
}

static int __driver_attach(struct device *dev, void *data) //drivers/base/dd.c

{

if (!driver_match_device(drv, dev))
return 0;

driver_probe_device(drv, dev);

}

static inline int driver_match_device(struct device_driver *drv, //drivers/base/base.h
struct device *dev)
{

//这里调用了mmc总线的match函数
return drv->bus->match ? drv->bus->match(dev, drv) : 1;
}

static int mmc_bus_match(struct device *dev, struct device_driver *drv) //drivers\mmc\core\bus.c
{

//mmc总线的match直接返回了1
return 1;
}