ARM-Linux驱动--DM9000网卡驱动分析（三）

内核版本：2.6.35

主机平台：Ubuntu11.04

内核版本：2.6.39

交叉编译器：arm-linuc-gcc4.3.2

原创作品，转载请标明出处http://blog.csdn.net/yming0221/article/details/6615027

本文接上文

ARM-Linux驱动--DM9000网卡驱动分析（一）

ARM-Linux驱动--DM9000网卡驱动分析（二）

下面开始看网卡设备的打开、关闭函数和操作函数

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static const struct net_device_ops dm9000_netdev_ops = {

.ndo_open = dm9000_open,

.ndo_stop = dm9000_stop,

.ndo_start_xmit = dm9000_start_xmit,

.ndo_tx_timeout = dm9000_timeout,

.ndo_set_multicast_list = dm9000_hash_table,

.ndo_do_ioctl = dm9000_ioctl,

.ndo_change_mtu = eth_change_mtu,

.ndo_validate_addr = eth_validate_addr,

.ndo_set_mac_address = eth_mac_addr,

#ifdef CONFIG_NET_POLL_CONTROLLER

.ndo_poll_controller = dm9000_poll_controller,

#endif

};

1、DM9000的打开函数

由于在函数alloc_netdev_mq()中分配net_device和网卡的私有数据是一起分配的，详见函数的实现

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struct net_device *alloc_netdev_mq(int sizeof_priv, const char *name,

void (*setup)(struct net_device *), unsigned int queue_count)

{

...................

alloc_size = sizeof(struct net_device);

if (sizeof_priv) {

alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);

alloc_size += sizeof_priv;

}

alloc_size += NETDEV_ALIGN - 1;

p = kzalloc(alloc_size, GFP_KERNEL);

if (!p) {

printk(KERN_ERR "alloc_netdev: Unable to allocate device.\n");

return NULL;

}

tx = kcalloc(queue_count, sizeof(struct netdev_queue), GFP_KERNEL);

if (!tx) {

printk(KERN_ERR "alloc_netdev: Unable to allocate "

"tx qdiscs.\n");

goto free_p;

}

#ifdef CONFIG_RPS

rx = kcalloc(queue_count, sizeof(struct netdev_rx_queue), GFP_KERNEL);

if (!rx) {

printk(KERN_ERR "alloc_netdev: Unable to allocate "

"rx queues.\n");

goto free_tx;

}

..............

}

所以使用函数netdev_priv()函数返回的是网卡的私有数据的地址，函数的实现如下：

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static inline void *netdev_priv(const struct net_device *dev)

{

return (char *)dev + ALIGN(sizeof(struct net_device), NETDEV_ALIGN);

}

这样两者会同时生存和消失。

dm9000_open()函数

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static int

dm9000_open(struct net_device *dev)

{

board_info_t *db = netdev_priv(dev);

unsigned long irqflags = db->irq_res->flags & IRQF_TRIGGER_MASK;

if (netif_msg_ifup(db))

dev_dbg(db->dev, "enabling %s\n", dev->name);

if (irqflags == IRQF_TRIGGER_NONE)

dev_warn(db->dev, "WARNING: no IRQ resource flags set.\n");

irqflags |= IRQF_SHARED;

if (request_irq(dev->irq, dm9000_interrupt, irqflags, dev->name, dev))

return -EAGAIN;

dm9000_reset(db);

dm9000_init_dm9000(dev);

db->dbug_cnt = 0;

mii_check_media(&db->mii, netif_msg_link(db), 1);

netif_start_queue(dev);

dm9000_schedule_poll(db);

return 0;

}

2、网卡关闭函数

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static int

dm9000_stop(struct net_device *ndev)

{

board_info_t *db = netdev_priv(ndev);

if (netif_msg_ifdown(db))

dev_dbg(db->dev, "shutting down %s\n", ndev->name);

cancel_delayed_work_sync(&db->phy_poll);

netif_stop_queue(ndev);

netif_carrier_off(ndev);

free_irq(ndev->irq, ndev);

dm9000_shutdown(ndev);

return 0;

}

下面是调用的dm9000_shutdown(ndev)函数，该函数的功能是复位phy，配置寄存器GPR位0为1，关闭dm9000电源，配置寄存器IMR位7为1，disable中断，配置寄存器RCR，disable接收

函数如下:

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static void

dm9000_shutdown(struct net_device *dev)

{

board_info_t *db = netdev_priv(dev);

dm9000_phy_write(dev, 0, MII_BMCR, BMCR_RESET);