我是USB的初学者。我想学习usb驱动程序。我正在使用现有的usbkbd代码在键盘上测试代码。目前，我的目的只是在每个按键时调用完整的回调。我从system和depmod ed中删除了usbkbd，hid-generic。
在每个按键上，我可以在dmesg中看到设备断开连接，探测器被调用但没有回调。
INPUT：dmesg：
[ 5846.796941] usb 2-2: new low-speed USB device number 47 using xhci_hcd
[ 5846.935078] usb 2-2: New USB device found, idVendor=1a2c, idProduct=0002
[ 5846.935082] usb 2-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 5846.935084] usb 2-2: Product: USB Keykoard
[ 5846.935086] usb 2-2: Manufacturer: USB
[ 5846.935290] usb 2-2: ep 0x81 - rounding interval to 64 microframes, ep desc says 80 microframes
[ 5846.935297] usb 2-2: ep 0x82 - rounding interval to 64 microframes, ep desc says 80 microframes
[ 5846.935718] usb_test: usb_kbd_probe : probe is called for kbd
[ 5846.935722] usb_test: usb_kbd_probe : bNumEndpoints = 1,bInterfaceNumber = 0
[ 5846.935725] usb_test: usb_kbd_probe : error = 0
[ 5846.935727] usb_test: usb_kbd_probe : usb_fill_int_urb, bInterval = 10
[ 5846.935803] usb_test: usb_kbd_probe : probe is called for kbd
[ 5846.935805] usb_test: usb_kbd_probe : bNumEndpoints = 1,bInterfaceNumber = 1
[ 5846.935807] usb_test: usb_kbd_probe : error = 0
[ 5846.935809] usb_test: usb_kbd_probe : usb_fill_int_urb, bInterval = 10
[ 5847.466506] usbcore: registered new interface driver usbhid
[ 5847.466510] usbhid: USB HID core driver
[ 6108.600030] usb 2-2: USB disconnect, device number 47
[ 6109.384486] usb 2-2: new low-speed USB device number 48 using xhci_hcd
[ 6109.578129] usb 2-2: New USB device found, idVendor=1a2c, idProduct=0002
[ 6109.578133] usb 2-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 6109.578135] usb 2-2: Product: USB Keykoard
[ 6109.578137] usb 2-2: Manufacturer: USB
[ 6109.578284] usb 2-2: ep 0x81 - rounding interval to 64 microframes, ep desc says 80 microframes
[ 6109.578291] usb 2-2: ep 0x82 - rounding interval to 64 microframes, ep desc says 80 microframes
[ 6109.579300] usb_test: usb_kbd_probe : probe is called for kbd
[ 6109.579313] usb_test: usb_kbd_probe : bNumEndpoints = 1,bInterfaceNumber = 0
[ 6109.579321] usb_test: usb_kbd_probe : error = 0
[ 6109.579322] usb_test: usb_kbd_probe : usb_fill_int_urb, bInterval = 10
[ 6109.579453] usb_test: usb_kbd_probe : probe is called for kbd
[ 6109.579456] usb_test: usb_kbd_probe : bNumEndpoints = 1,bInterfaceNumber = 1
[ 6109.579460] usb_test: usb_kbd_probe : error = 0
[ 6109.579461] usb_test: usb_kbd_probe : usb_fill_int_urb, bInterval = 10
代码是：
#define DEBUG
#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>
MODULE_AUTHOR("XYZ");
MODULE_DESCRIPTION("");
MODULE_LICENSE("GPL");
struct usb_kbd {
struct usb_device *usbdev;
unsigned char old[8];
struct urb *irq;
unsigned char newleds;
unsigned char *new;
dma_addr_t new_dma;
bool led_urb_submitted;
};
static void usb_kbd_irq(struct urb *urb)
{
struct usb_kbd *kbd = urb->context;
int i;
pr_debug("usb_kbd_irq : compete is called\n");
switch (urb->status) {
case 0: /* success */
break;
case -ECONNRESET: /* unlink */
case -ENOENT:
case -ESHUTDOWN:
return;
default: /* error */
goto resubmit;
}
resubmit:
if (usb_submit_urb (urb, GFP_ATOMIC))
hid_err(urb->dev, "can't resubmit intr, %s-%s/input0, status %d",
kbd->usbdev->bus->bus_name,
kbd->usbdev->devpath, i);
}
static int usb_kbd_alloc_mem(struct usb_device *dev, struct usb_kbd *kbd)
{
if (!(kbd->irq = usb_alloc_urb(0, GFP_KERNEL)))
return -1;
if (!(kbd->new = usb_alloc_coherent(dev, 8, GFP_ATOMIC, &kbd->new_dma)))
return -2;
return 0;
}
static void usb_kbd_free_mem(struct usb_device *dev, struct usb_kbd *kbd)
{
usb_free_urb(kbd->irq);
usb_free_coherent(dev, 8, kbd->new, kbd->new_dma);
}
static int usb_kbd_probe(struct usb_interface *iface,
const struct usb_device_id *id)
{
struct usb_device *dev = interface_to_usbdev(iface);
struct usb_host_interface *interface;
struct usb_endpoint_descriptor *endpoint;
struct usb_kbd *kbd;
int i, pipe, maxp;
int error = -ENOMEM;
pr_debug("usb_kbd_probe : probe is called for kbd\n");
interface = iface->cur_altsetting;
pr_debug("usb_kbd_probe : bNumEndpoints = %d,bInterfaceNumber = %d\n",
interface->desc.bNumEndpoints,
interface->desc.bInterfaceNumber);
if (interface->desc.bNumEndpoints != 1)
return -ENODEV;
endpoint = &interface->endpoint[0].desc;
if (!usb_endpoint_is_int_in(endpoint))
return -ENODEV;
pipe = usb_rcvintpipe(dev, endpoint->bEndpointAddress);
maxp = usb_maxpacket(dev, pipe, usb_pipeout(pipe));
kbd = kzalloc(sizeof(struct usb_kbd), GFP_KERNEL);
error = usb_kbd_alloc_mem(dev, kbd);
pr_debug("usb_kbd_probe : error = %d\n", error);
if (error < 0) {
pr_debug("usb_kbd_probe : falied to usb_kbd_alloc_mem\n");
goto fail2;
}
kbd->usbdev = dev;
pr_debug("usb_kbd_probe : usb_fill_int_urb, bInterval = %d\n",
endpoint->bInterval);
usb_fill_int_urb(kbd->irq, dev, pipe,
kbd->new, (maxp > 8 ? 8 : maxp),
usb_kbd_irq, kbd, endpoint->bInterval);
// kbd->irq->transfer_dma = kbd->new_dma;
// kbd->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
usb_set_intfdata(iface, kbd);
return 0;
fail2:
usb_kbd_free_mem(dev, kbd);
kfree(kbd);
return error;
}
static void usb_kbd_disconnect(struct usb_interface *intf)
{
struct usb_kbd *kbd = usb_get_intfdata (intf);
usb_set_intfdata(intf, NULL);
if (kbd) {
usb_kill_urb(kbd->irq);
usb_kbd_free_mem(interface_to_usbdev(intf), kbd);
kfree(kbd);
}
}
static struct usb_device_id usb_kbd_id_table [] = {
{ USB_DEVICE(0x1a2c, 0x0002) },
{ USB_DEVICE(0x0000, 0x0538) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE (usb, usb_kbd_id_table);
static struct usb_driver usb_kbd_driver = {
.name = "usbkbd_new",
.probe = usb_kbd_probe,
.disconnect = usb_kbd_disconnect,
.id_table = usb_kbd_id_table,
};
module_usb_driver(usb_kbd_driver);
任何帮助都将不胜感激。
代码是否正确？
它应该如何工作？
每次按键时断开连接的原因...... ???
谢谢， Pritam
答案 0 :(得分：0)
填写后需要提交urb。 因此，超时正在发生，设备正在与核心断开连接......
如果我被误解，请纠正我。