usb驱动之打印usb设备信息（二）

以下是打印鼠标左右键及其他输入的源代码，详细说明见https://www.cnblogs.com/zhu-g5may/p/9309381.html

 /*参考/drivers/hid/usbhid/usbmouse.c*/

 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/usb/input.h>
 #include <linux/hid.h>

 static struct urb *mouse_urb;
 static int len;
 static char *buf;
 static dma_addr_t mouse_dma;

 static const struct usb_device_id mouse_table[] = {
     { USB_INTERFACE_INFO(USB_INTERFACE_CLASS_HID, USB_INTERFACE_SUBCLASS_BOOT,
         USB_INTERFACE_PROTOCOL_MOUSE) },        /* mouse */
     { }/* Terminating entry */
 };

 MODULE_DEVICE_TABLE (usb, mouse_table);

 static void usb_mouse_irq(struct urb *urb)
 {
      static int cnt = ;
      int i;
      printk("data %d : \n",++cnt);
      for(i = ; i < len; i++){
         printk("0x%02x\n",buf[i]);
      }
      usb_submit_urb(mouse_urb, GFP_KERNEL);
 }

 static int mouse_probe(struct usb_interface *intf,
              const struct usb_device_id *id)
 {
       int pipe;
       struct usb_device *mdev = interface_to_usbdev(intf);  //设备
       struct usb_endpoint_descriptor *endpoint;
       struct usb_host_interface *interface;

       interface = intf->cur_altsetting;  //接口
       if (interface->desc.bNumEndpoints != )
         return -ENODEV;

       endpoint = &interface->endpoint[].desc;  //端点
       if (!usb_endpoint_is_int_in(endpoint))
         return -ENODEV;

       len = endpoint->wMaxPacketSize;    //长度(多少字节)

       buf = usb_alloc_coherent(mdev, len, GFP_ATOMIC, &mouse_dma); //传输buffer，目的
 
       pipe=usb_rcvintpipe(mdev,endpoint->bEndpointAddress);  //源

       mouse_urb = usb_alloc_urb(, GFP_KERNEL);    

       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
       mouse_urb->transfer_dma = mouse_dma;
       mouse_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

       usb_submit_urb(mouse_urb, GFP_KERNEL);

      return ;
 }

 static void mouse_disconnect(struct usb_interface *intf)
 {
       struct usb_device *mdev = interface_to_usbdev(intf);  //设备
       usb_kill_urb(mouse_urb);
       usb_free_urb(mouse_urb);
       usb_free_coherent(mdev, len, buf, mouse_dma);
 }

 static struct usb_driver usb_driver = {
     .name        = "mouse",
     .probe        = mouse_probe,
     .disconnect = mouse_disconnect,
     .id_table    = mouse_table,
 };

 static int usb_drv_init(void)
 {
       usb_register(&usb_driver);
       return ;
 }

 static void usb_drv_exit(void)
 {
       usb_deregister(&usb_driver);
 }

 module_init(usb_drv_init);
 module_exit(usb_drv_exit);
 //module_usb_driver(usb_driver);

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("1653699780@qq.com");