drivers/hid/usbhid/usbkbd.c

Source file repositories/reference/linux-study-clean/drivers/hid/usbhid/usbkbd.c

File Facts

System
Linux kernel
Corpus path
drivers/hid/usbhid/usbkbd.c
Extension
.c
Size
11162 bytes
Lines
404
Domain
Driver Families
Bucket
drivers/hid
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct usb_kbd {
	struct input_dev *dev;
	struct usb_device *usbdev;
	unsigned char old[8];
	struct urb *irq, *led;
	unsigned char newleds;
	char name[128];
	char phys[64];

	unsigned char *new;
	struct usb_ctrlrequest *cr;
	unsigned char *leds;
	dma_addr_t new_dma;
	dma_addr_t leds_dma;

	spinlock_t leds_lock;
	bool led_urb_submitted;

};

static void usb_kbd_irq(struct urb *urb)
{
	struct usb_kbd *kbd = urb->context;
	int i;

	switch (urb->status) {
	case 0:			/* success */
		break;
	case -ECONNRESET:	/* unlink */
	case -ENOENT:
	case -ESHUTDOWN:
		return;
	/* -EPIPE:  should clear the halt */
	default:		/* error */
		goto resubmit;
	}

	for (i = 0; i < 8; i++)
		input_report_key(kbd->dev, usb_kbd_keycode[i + 224], (kbd->new[0] >> i) & 1);

	for (i = 2; i < 8; i++) {

		if (kbd->old[i] > 3 && memscan(kbd->new + 2, kbd->old[i], 6) == kbd->new + 8) {
			if (usb_kbd_keycode[kbd->old[i]])
				input_report_key(kbd->dev, usb_kbd_keycode[kbd->old[i]], 0);
			else
				hid_info(urb->dev,
					 "Unknown key (scancode %#x) released.\n",
					 kbd->old[i]);
		}

		if (kbd->new[i] > 3 && memscan(kbd->old + 2, kbd->new[i], 6) == kbd->old + 8) {
			if (usb_kbd_keycode[kbd->new[i]])
				input_report_key(kbd->dev, usb_kbd_keycode[kbd->new[i]], 1);
			else
				hid_info(urb->dev,
					 "Unknown key (scancode %#x) pressed.\n",
					 kbd->new[i]);
		}
	}

	input_sync(kbd->dev);

	memcpy(kbd->old, kbd->new, 8);

resubmit:
	i = usb_submit_urb (urb, GFP_ATOMIC);
	if (i)
		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_event(struct input_dev *dev, unsigned int type,
			 unsigned int code, int value)
{
	unsigned long flags;
	struct usb_kbd *kbd = input_get_drvdata(dev);

	if (type != EV_LED)
		return -1;

	spin_lock_irqsave(&kbd->leds_lock, flags);
	kbd->newleds = (!!test_bit(LED_KANA,    dev->led) << 4) | (!!test_bit(LED_COMPOSE, dev->led) << 3) |
		       (!!test_bit(LED_SCROLLL, dev->led) << 2) | (!!test_bit(LED_CAPSL,   dev->led) << 1) |
		       (!!test_bit(LED_NUML,    dev->led));

	if (kbd->led_urb_submitted){
		spin_unlock_irqrestore(&kbd->leds_lock, flags);
		return 0;

Annotation

Implementation Notes