usb驱动之打印usb设备信息（二）

 1 /*参考/drivers/hid/usbhid/usbmouse.c*/
 2 
 3 #include <linux/kernel.h>
 4 #include <linux/slab.h>
 5 #include <linux/module.h>
 6 #include <linux/init.h>
 7 #include <linux/usb/input.h>
 8 #include <linux/hid.h>
 9 
10 static struct urb *mouse_urb;
11 static int len;
12 static char *buf;
13 static dma_addr_t mouse_dma;
14 
15 static const struct usb_device_id mouse_table[] = {
16     { USB_INTERFACE_INFO(USB_INTERFACE_CLASS_HID, USB_INTERFACE_SUBCLASS_BOOT,
17         USB_INTERFACE_PROTOCOL_MOUSE) },        /* mouse */
18     { }/* Terminating entry */
19 };
20 
21 MODULE_DEVICE_TABLE (usb, mouse_table);
22 
23 static void usb_mouse_irq(struct urb *urb)
24 {
25      static int cnt = 0;
26      int i;
27      printk("data %d : 
",++cnt);
28      for(i = 0; i < len; i++){
29         printk("0x%02x
",buf[i]);
30      }
31      usb_submit_urb(mouse_urb, GFP_KERNEL);
32 }
33 
34 static int mouse_probe(struct usb_interface *intf,
35              const struct usb_device_id *id)
36 {
37       int pipe;
38       struct usb_device *mdev = interface_to_usbdev(intf);  //设备
39       struct usb_endpoint_descriptor *endpoint;
40       struct usb_host_interface *interface;
41       
42       interface = intf->cur_altsetting;  //接口
43       if (interface->desc.bNumEndpoints != 1)
44         return -ENODEV;
45       
46       endpoint = &interface->endpoint[0].desc;  //端点
47       if (!usb_endpoint_is_int_in(endpoint))
48         return -ENODEV;
49       
50       len = endpoint->wMaxPacketSize;    //长度(多少字节)
51 
52       buf = usb_alloc_coherent(mdev, len, GFP_ATOMIC, &mouse_dma); //传输buffer，目的
53       
54       pipe=usb_rcvintpipe(mdev,endpoint->bEndpointAddress);  //源
55      
56       mouse_urb = usb_alloc_urb(0, GFP_KERNEL);    
57       
58       usb_fill_int_urb(mouse_urb,mdev,pipe,buf,len,usb_mouse_irq, NULL, endpoint->bInterval);   //初始化中断型urb结构体
59       mouse_urb->transfer_dma = mouse_dma;
60       mouse_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
61       
62       usb_submit_urb(mouse_urb, GFP_KERNEL);
63        
64      return 0;
65 }
66 
67 static void mouse_disconnect(struct usb_interface *intf)
68 {
69       struct usb_device *mdev = interface_to_usbdev(intf);  //设备
70       usb_kill_urb(mouse_urb);
71       usb_free_urb(mouse_urb);
72       usb_free_coherent(mdev, len, buf, mouse_dma);
73 }
74 
75 static struct usb_driver usb_driver = {
76     .name        = "mouse",
77     .probe        = mouse_probe,
78     .disconnect = mouse_disconnect,
79     .id_table    = mouse_table,
80 };
81 
82 static int usb_drv_init(void)
83 {
84       usb_register(&usb_driver);
85       return 0;
86 }
87 
88 static void usb_drv_exit(void)
89 {
90       usb_deregister(&usb_driver);
91 }
92 
93 module_init(usb_drv_init);
94 module_exit(usb_drv_exit);
95 //module_usb_driver(usb_driver);
96 
97 MODULE_LICENSE("GPL");
98 MODULE_AUTHOR("1653699780@qq.com");