參考 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 input_dev *uk_dev;
static char *usb_buf;
static dma_addr_t usb_buf_phys;
static int len;
static struct urb *uk_urb;
static struct usb_device_id usbmouse_as_key_id_table [] = {
{ USB_INTERFACE_INFO(USB_INTERFACE_CLASS_HID, USB_INTERFACE_SUBCLASS_BOOT,
USB_INTERFACE_PROTOCOL_MOUSE) },
//{USB_DEVICE(0x1234,0x5678)},
{ } /* Terminating entry */
};
static void usbmouse_as_key_irq(struct urb *urb)
{
static unsigned char pre_val;
/* USB鼠標數據含義
* data[0]: bit0-左鍵, 1-按下, 0-鬆開
* bit1-右鍵, 1-按下, 0-鬆開
* bit2-中鍵, 1-按下, 0-鬆開
*
*/
if ((pre_val & (1<<0)) != (usb_buf[0] & (1<<0)))
{
/* 左鍵發生了變化 */
input_event(uk_dev, EV_KEY, KEY_L, (usb_buf[0] & (1<<0)) ? 1 : 0);
input_sync(uk_dev);
}
if ((pre_val & (1<<1)) != (usb_buf[0] & (1<<1)))
{
/* 右鍵發生了變化 */
input_event(uk_dev, EV_KEY, KEY_S, (usb_buf[0] & (1<<1)) ? 1 : 0);
input_sync(uk_dev);
}
if ((pre_val & (1<<2)) != (usb_buf[0] & (1<<2)))
{
/* 中鍵發生了變化 */
input_event(uk_dev, EV_KEY, KEY_ENTER, (usb_buf[0] & (1<<2)) ? 1 : 0);
input_sync(uk_dev);
}
pre_val = usb_buf[0];
/* 重新提交urb */
usb_submit_urb(uk_urb, GFP_KERNEL);
}
static int usbmouse_as_key_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
struct usb_device *dev = interface_to_usbdev(intf);
struct usb_host_interface *interface;
struct usb_endpoint_descriptor *endpoint;
int pipe;
interface = intf->cur_altsetting;
endpoint = &interface->endpoint[0].desc;
/* a. 分配一個input_dev */
uk_dev = input_allocate_device();
/* b. 設置 */
/* b.1 能產生哪類事件 */
set_bit(EV_KEY, uk_dev->evbit);
set_bit(EV_REP, uk_dev->evbit);
/* b.2 能產生哪些事件 */
set_bit(KEY_L, uk_dev->keybit);
set_bit(KEY_S, uk_dev->keybit);
set_bit(KEY_ENTER, uk_dev->keybit);
/* c. 註冊 */
input_register_device(uk_dev);
/* d. 硬件相關操作 */
/* 數據傳輸3要素: 源,目的,長度 */
/* 源: USB設備的某個端點 */
pipe = usb_rcvintpipe(dev, endpoint->bEndpointAddress);
/* 長度: */
len = endpoint->wMaxPacketSize;
/* 目的: */
usb_buf = usb_buffer_alloc(dev, len, GFP_ATOMIC, &usb_buf_phys);
/* 使用"3要素" */
/* 分配usb request block */
uk_urb = usb_alloc_urb(0, GFP_KERNEL);
/* 使用"3要素設置urb" */
usb_fill_int_urb(uk_urb, dev, pipe, usb_buf, len, usbmouse_as_key_irq, NULL, endpoint->bInterval);
uk_urb->transfer_dma = usb_buf_phys;
uk_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
/* 使用URB */
usb_submit_urb(uk_urb, GFP_KERNEL);
return 0;
}
static void usbmouse_as_key_disconnect(struct usb_interface *intf)
{
struct usb_device *dev = interface_to_usbdev(intf);
//printk("disconnect usbmouse!\n");
usb_kill_urb(uk_urb);
usb_free_urb(uk_urb);
usb_buffer_free(dev, len, usb_buf, usb_buf_phys);
input_unregister_device(uk_dev);
input_free_device(uk_dev);
}
/* 1. 分配/設置usb_driver */
static struct usb_driver usbmouse_as_key_driver = {
.name = "usbmouse_as_key_",
.probe
= usbmouse_as_key_probe,
.disconnect
= usbmouse_as_key_disconnect,
.id_table
= usbmouse_as_key_id_table,
};
static int usbmouse_as_key_init(void)
{
/* 2. 註冊 */
usb_register(&usbmouse_as_key_driver);
return 0;
}
static void usbmouse_as_key_exit(void)
{
usb_deregister(&usbmouse_as_key_driver);
}
module_init(usbmouse_as_key_init);
module_exit(usbmouse_as_key_exit);
MODULE_LICENSE("GPL");
測試:
make menuconfig去掉原來的USB鼠標驅動
-> Device Drivers
-> HID Devices
<> USB Human Interface Device (full HID) support
1. insmod usbmouse_as_key.ko
2. ls /dev/event*
3. 接上USB鼠標
4. ls /dev/event*
5. cat /dev/tty1 然後按鼠標鍵
6. hexdump /dev/event0