10-实例_PCI骨架程序

21.2.2 实例：PCI骨架程序

drivers/net/pci-skeleton.c给出了一个PCI接口网络设备驱动程序的“骨架”，其pci_driver中probe()成员函数netdrv_init_one()及其调用的netdrv_init_board()完成了PCI设备初始化及对应的网络设备注册工作，代码清单21.8所示为这两个函数的实现。

代码清单21.8 pci-skeleton设备驱动的probe()函数

1 static int __devinit netdrv_init_one (struct pci_dev *pdev,

2 const struct pci_device_id *ent)

3 {

4 struct net_device *dev = NULL;

5 struct netdrv_private *tp;

6 ...

7 i = netdrv_init_board (pdev, &dev, &ioaddr);

8 ...

9

10 dev→open = netdrv_open;

11 dev→hard_start_xmit = netdrv_start_xmit;

12 dev→stop = netdrv_close;

13 dev→set_multicast_list = netdrv_set_rx_mode;

14 dev→do_ioctl = netdrv_ioctl;

15 dev→tx_timeout = netdrv_tx_timeout;

16 dev→watchdog_timeo = TX_TIMEOUT;

17

18 dev→irq = pdev→irq;

19 dev→base_addr = (unsigned long) ioaddr;

20

21 tp = netdev_priv(dev);

22

23 ...

24 pci_set_drvdata(pdev, dev);

25 ...

26 return 0;

27 }

28

29 static int __devinit netdrv_init_board (struct pci_dev *pdev,

30 struct net_device **dev_out,

31 void **ioaddr_out)

32 {

33 ...

34 dev = alloc_etherdev (sizeof (*tp));

35 if (dev == NULL) {

36 dev_err(&pdev→dev, "unable to alloc new ethernet\n");

37 DPRINTK ("EXIT, returning -ENOMEM\n");

38 return -ENOMEM;

39 }

40 SET_NETDEV_DEV(dev, &pdev→dev);

41 tp = netdev_priv(dev);

42 ...

43 }

从上述代码可以看出，probe()函数中进行了网络设备的初始化和注册。pci_driver的remove()成员函数完成相反的工作，即注销网络设备，如代码清单21.9所示。

代码清单21.9 pci-skeleton设备驱动的remove()函数

1 static void __devexit netdrv_remove_one (struct pci_dev *pdev)

2 {

3 struct net_device *dev = pci_get_drvdata (pdev);

4 struct netdrv_private *np;

5

6 ...

7 np = netdev_priv(dev);

8 assert (np != NULL);

9

10 unregister_netdev (dev);

11

12 #ifndef USE_IO_OPS

13 iounmap (np→mmio_addr);

14 #endif / !USE_IO_OPS /

15

16 pci_release_regions (pdev);

17

18 free_netdev (dev);

19

20 pci_set_drvdata (pdev, NULL);

21

22 pci_disable_device (pdev);

23

24 DPRINTK ("EXIT\n");

25 }

/drivers/net/pci-skeleton.c中定义的pci_device_id结构体数组及MODULE_DEVICE_TABLE导出代码如清单21.10所示。

代码清单21.10 PCI设备驱动的pci_device_id数组及MODULE_DEVICE_TABLE

1 static struct pci_device_id netdrv_pci_tbl[] = {

2 {0x10ec, 0x8139, PCI_ANY_ID, PCI_ANY_ID, 0, 0, RTL8139 },

3 {0x10ec, 0x8138, PCI_ANY_ID, PCI_ANY_ID, 0, 0, NETDRV_CB },

4 {0x1113, 0x1211, PCI_ANY_ID, PCI_ANY_ID, 0, 0, SMC1211TX },

5 / {0x1113, 0x1211, PCI_ANY_ID, PCI_ANY_ID, 0, 0, MPX5030 },/

6 {0x1500, 0x1360, PCI_ANY_ID, PCI_ANY_ID, 0, 0, DELTA8139 },

7 {0x4033, 0x1360, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ADDTRON8139 },

8 {0,}

9 };

10 MODULE_DEVICE_TABLE (pci, netdrv_pci_tbl);

除此之外，pci-skeleton的主体即是完成网络设备驱动相关的工作，完全符合本书第6章的模板。