U-boot 驱动模型

跟Linux内核类似，U-boot现在也在驱动层使用驱动模型（Driver Model）了，几个核心的结构体：

udevice结构体：表示一个设备

#include<dm/device.h>
struct udevice {
    const struct driver *driver;
    const char *name;
    void *platdata;
    void *parent_platdata;
    void *uclass_platdata;
    ofnode node;
    ulong driver_data;
    struct udevice *parent;
    void *priv;
    struct uclass *uclass;
    void *uclass_priv;
    void *parent_priv;
    struct list_head uclass_node;
    struct list_head child_head;
    struct list_head sibling_node;
    uint32_t flags;
    int req_seq;
    int seq;
#ifdef CONFIG_DEVRES
    struct list_head devres_head;
#endif
}

driver结构体：udevice设备对应的驱动

#include<dm/device.h>
struct driver {
    char *name;
    enum uclass_id id;
    const struct udevice_id *of_match;
    int (*bind)(struct udevice *dev);
    int (*probe)(struct udevice *dev);
    int (*remove)(struct udevice *dev);
    int (*unbind)(struct udevice *dev);
    int (*ofdata_to_platdata)(struct udevice *dev);
    int (*child_post_bind)(struct udevice *dev);
    int (*child_pre_probe)(struct udevice *dev);
    int (*child_post_remove)(struct udevice *dev);
    int priv_auto_alloc_size;
    int platdata_auto_alloc_size;
    int per_child_auto_alloc_size;
    int per_child_platdata_auto_alloc_size;
    const void *ops;    /* driver-specific operations */
    uint32_t flags;
};

uclass结构体：某一类设备的抽象，提供统一的接口

#include<dm/uclass.h>
struct uclass {
    void *priv;
    struct uclass_driver *uc_drv;
    struct list_head dev_head;
    struct list_head sibling_node;
#ifdef CONFIG_USING_KERNEL_DTB_V2
    struct list_head *u_boot_dev_head;
#endif
};

uclass_driver结构体：设备类驱动，某一类设备统一的驱动

#include<dm/uclass.h>
struct uclass_driver {
    const char *name;
    enum uclass_id id;
    int (*post_bind)(struct udevice *dev);
    int (*pre_unbind)(struct udevice *dev);
    int (*pre_probe)(struct udevice *dev);
    int (*post_probe)(struct udevice *dev);
    int (*pre_remove)(struct udevice *dev);
    int (*child_post_bind)(struct udevice *dev);
    int (*child_pre_probe)(struct udevice *dev);
    int (*init)(struct uclass *class);
    int (*destroy)(struct uclass *class);
    int priv_auto_alloc_size;
    int per_device_auto_alloc_size;
    int per_device_platdata_auto_alloc_size;
    int per_child_auto_alloc_size;
    int per_child_platdata_auto_alloc_size;
    const void *ops;
    uint32_t flags;
}