drivers/input/tablet/kbtab.c

Source file repositories/reference/linux-study-clean/drivers/input/tablet/kbtab.c

File Facts

System
Linux kernel
Corpus path
drivers/input/tablet/kbtab.c
Extension
.c
Size
5100 bytes
Lines
205
Domain
Driver Families
Bucket
drivers/input
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 kbtab {
	unsigned char *data;
	dma_addr_t data_dma;
	struct input_dev *dev;
	struct usb_interface *intf;
	struct urb *irq;
	char phys[32];
};

static void kbtab_irq(struct urb *urb)
{
	struct kbtab *kbtab = urb->context;
	unsigned char *data = kbtab->data;
	struct input_dev *dev = kbtab->dev;
	int pressure;
	int retval;

	switch (urb->status) {
	case 0:
		/* success */
		break;
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
		/* this urb is terminated, clean up */
		dev_dbg(&kbtab->intf->dev,
			"%s - urb shutting down with status: %d\n",
			__func__, urb->status);
		return;
	default:
		dev_dbg(&kbtab->intf->dev,
			"%s - nonzero urb status received: %d\n",
			__func__, urb->status);
		goto exit;
	}


	input_report_key(dev, BTN_TOOL_PEN, 1);

	input_report_abs(dev, ABS_X, get_unaligned_le16(&data[1]));
	input_report_abs(dev, ABS_Y, get_unaligned_le16(&data[3]));

	/*input_report_key(dev, BTN_TOUCH , data[0] & 0x01);*/
	input_report_key(dev, BTN_RIGHT, data[0] & 0x02);

	pressure = data[5];
	if (kb_pressure_click == -1)
		input_report_abs(dev, ABS_PRESSURE, pressure);
	else
		input_report_key(dev, BTN_LEFT, pressure > kb_pressure_click ? 1 : 0);

	input_sync(dev);

 exit:
	retval = usb_submit_urb(urb, GFP_ATOMIC);
	if (retval)
		dev_err(&kbtab->intf->dev,
			"%s - usb_submit_urb failed with result %d\n",
			__func__, retval);
}

static const struct usb_device_id kbtab_ids[] = {
	{ USB_DEVICE(USB_VENDOR_ID_KBGEAR, 0x1001), .driver_info = 0 },
	{ }
};

MODULE_DEVICE_TABLE(usb, kbtab_ids);

static int kbtab_open(struct input_dev *dev)
{
	struct kbtab *kbtab = input_get_drvdata(dev);
	struct usb_device *udev = interface_to_usbdev(kbtab->intf);

	kbtab->irq->dev = udev;
	if (usb_submit_urb(kbtab->irq, GFP_KERNEL))
		return -EIO;

	return 0;
}

static void kbtab_close(struct input_dev *dev)
{
	struct kbtab *kbtab = input_get_drvdata(dev);

	usb_kill_urb(kbtab->irq);
}

static int kbtab_probe(struct usb_interface *intf, const struct usb_device_id *id)
{
	struct usb_device *dev = interface_to_usbdev(intf);

Annotation

Implementation Notes