keyspan_remote.c

底层驱动开发

			input_report_key(&remote->input, keyspan_key_table[message.button], 0);
			input_sync(&remote->input);
			remote->toggle = message.toggle;
		}

		remote->stage = 0;
		break;
	}
}

/*
 * Routine for sending all the initialization messages to the remote.
 */
static int keyspan_setup(struct usb_device* dev)
{
	int retval = 0;

	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
				 0x11, 0x40, 0x5601, 0x0, NULL, 0, 0);
	if (retval) {
		dev_dbg(&dev->dev, "%s - failed to set bit rate due to error: %d\n",
			__FUNCTION__, retval);
		return(retval);
	}

	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
				 0x44, 0x40, 0x0, 0x0, NULL, 0, 0);
	if (retval) {
		dev_dbg(&dev->dev, "%s - failed to set resume sensitivity due to error: %d\n",
			__FUNCTION__, retval);
		return(retval);
	}

	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
				 0x22, 0x40, 0x0, 0x0, NULL, 0, 0);
	if (retval) {
		dev_dbg(&dev->dev, "%s - failed to turn receive on due to error: %d\n",
			__FUNCTION__, retval);
		return(retval);
	}

	dev_dbg(&dev->dev, "%s - Setup complete.\n", __FUNCTION__);
	return(retval);
}

/*
 * Routine used to handle a new message that has come in.
 */
static void keyspan_irq_recv(struct urb *urb, struct pt_regs *regs)
{
	struct usb_keyspan *dev = urb->context;
	int retval;

	/* Check our status in case we need to bail out early. */
	switch (urb->status) {
	case 0:
		break;

	/* Device went away so don't keep trying to read from it. */
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
		return;

	default:
		goto resubmit;
		break;
	}

	if (debug)
		keyspan_print(dev);

	keyspan_check_data(dev, regs);

resubmit:
	retval = usb_submit_urb(urb, GFP_ATOMIC);
	if (retval)
		err ("%s - usb_submit_urb failed with result: %d", __FUNCTION__, retval);
}

static int keyspan_open(struct input_dev *dev)
{
	struct usb_keyspan *remote = dev->private;

	if (remote->open++)
		return 0;

	remote->irq_urb->dev = remote->udev;
	if (usb_submit_urb(remote->irq_urb, GFP_KERNEL)) {
		remote->open--;
		return -EIO;
	}

	return 0;
}

static void keyspan_close(struct input_dev *dev)
{
	struct usb_keyspan *remote = dev->private;

	if (!--remote->open)
		usb_kill_urb(remote->irq_urb);
}

/*
 * Routine that sets up the driver to handle a specific USB device detected on the bus.
 */
static int keyspan_probe(struct usb_interface *interface, const struct usb_device_id *id)
{
	int i;
	int retval = -ENOMEM;
	char path[64];
	char *buf;
	struct usb_keyspan *remote = NULL;
	struct usb_host_interface *iface_desc;
	struct usb_endpoint_descriptor *endpoint;
	struct usb_device *udev = usb_get_dev(interface_to_usbdev(interface));

	/* allocate memory for our device state and initialize it */
	remote = kmalloc(sizeof(*remote), GFP_KERNEL);
	if (remote == NULL) {
		err("Out of memory\n");
		goto error;
	}
	memset(remote, 0x00, sizeof(*remote));

	remote->udev = udev;
	remote->interface = interface;
	remote->toggle = -1;	/* Set to -1 so we will always not match the toggle from the first remote message. */

	/* set up the endpoint information */
	/* use only the first in interrupt endpoint */
	iface_desc = interface->cur_altsetting;
	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
		endpoint = &iface_desc->endpoint[i].desc;

		if (!remote->in_endpoint &&
		    (endpoint->bEndpointAddress & USB_DIR_IN) &&
		    ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) == USB_ENDPOINT_XFER_INT)) {
			/* we found our interrupt in endpoint */
			remote->in_endpoint = endpoint;

			remote->in_buffer = usb_buffer_alloc(remote->udev, RECV_SIZE, SLAB_ATOMIC, &remote->in_dma);
			if (!remote->in_buffer) {
				retval = -ENOMEM;
				goto error;
			}
		}
	}

	if (!remote->in_endpoint) {
		err("Could not find interrupt input endpoint.\n");
		retval = -ENODEV;
		goto error;
	}

	remote->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!remote->irq_urb) {
		err("Failed to allocate urb.\n");
		retval = -ENOMEM;
		goto error;
	}

	retval = keyspan_setup(remote->udev);
	if (retval) {
		err("Failed to setup device.\n");
		retval = -ENODEV;
		goto error;
	}

	/*
	 * Setup the input system with the bits we are going to be reporting
	 */
	remote->input.evbit[0] = BIT(EV_KEY);		/* We will only report KEY events. */
	for (i = 0; i < 32; ++i) {
		if (keyspan_key_table[i] != KEY_RESERVED) {
			set_bit(keyspan_key_table[i], remote->input.keybit);
		}
	}

	remote->input.private = remote;
	remote->input.open = keyspan_open;
	remote->input.close = keyspan_close;

	usb_make_path(remote->udev, path, 64);
	sprintf(remote->phys, "%s/input0", path);

	remote->input.name = remote->name;
	remote->input.phys = remote->phys;
	remote->input.id.bustype = BUS_USB;
	remote->input.id.vendor = le16_to_cpu(remote->udev->descriptor.idVendor);
	remote->input.id.product = le16_to_cpu(remote->udev->descriptor.idProduct);
	remote->input.id.version = le16_to_cpu(remote->udev->descriptor.bcdDevice);

	if (!(buf = kmalloc(63, GFP_KERNEL))) {
		usb_buffer_free(remote->udev, RECV_SIZE, remote->in_buffer, remote->in_dma);
		kfree(remote);
		return -ENOMEM;
	}

	if (remote->udev->descriptor.iManufacturer &&
	    usb_string(remote->udev, remote->udev->descriptor.iManufacturer, buf, 63) > 0)
		strcat(remote->name, buf);

	if (remote->udev->descriptor.iProduct &&
	    usb_string(remote->udev, remote->udev->descriptor.iProduct, buf, 63) > 0)
		sprintf(remote->name, "%s %s", remote->name, buf);

	if (!strlen(remote->name))
		sprintf(remote->name, "USB Keyspan Remote %04x:%04x",
			remote->input.id.vendor, remote->input.id.product);

	kfree(buf);

	/*
	 * Initialize the URB to access the device. The urb gets sent to the device in keyspan_open()
	 */
	usb_fill_int_urb(remote->irq_urb,
			 remote->udev, usb_rcvintpipe(remote->udev, remote->in_endpoint->bEndpointAddress),
			 remote->in_buffer, RECV_SIZE, keyspan_irq_recv, remote,
			 remote->in_endpoint->bInterval);
	remote->irq_urb->transfer_dma = remote->in_dma;
	remote->irq_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

	/* we can register the device now, as it is ready */
	input_register_device(&remote->input);

	/* save our data pointer in this interface device */
	usb_set_intfdata(interface, remote);

	/* let the user know what node this device is now attached to */
	info("connected: %s on %s", remote->name, path);
	return 0;

error:
	/*
	 * In case of error we need to clean up any allocated buffers
	 */
	if (remote->irq_urb)
		usb_free_urb(remote->irq_urb);

	if (remote->in_buffer)
		usb_buffer_free(remote->udev, RECV_SIZE, remote->in_buffer, remote->in_dma);

	if (remote)
		kfree(remote);

	return retval;
}

/*
 * Routine called when a device is disconnected from the USB.
 */
static void keyspan_disconnect(struct usb_interface *interface)
{
	struct usb_keyspan *remote;

	/* prevent keyspan_open() from racing keyspan_disconnect() */
	lock_kernel();

	remote = usb_get_intfdata(interface);
	usb_set_intfdata(interface, NULL);

	if (remote) {	/* We have a valid driver structure so clean up everything we allocated. */
		input_unregister_device(&remote->input);
		usb_kill_urb(remote->irq_urb);
		usb_free_urb(remote->irq_urb);
		usb_buffer_free(interface_to_usbdev(interface), RECV_SIZE, remote->in_buffer, remote->in_dma);
		kfree(remote);
	}

	unlock_kernel();

	info("USB Keyspan now disconnected");
}

/*
 * Standard driver set up sections
 */
static struct usb_driver keyspan_driver =
{
	.owner =	THIS_MODULE,
	.name =		"keyspan_remote",
	.probe =	keyspan_probe,
	.disconnect =	keyspan_disconnect,
	.id_table =	keyspan_table
};

static int __init usb_keyspan_init(void)
{
	int result;

	/* register this driver with the USB subsystem */
	result = usb_register(&keyspan_driver);
	if (result)
		err("usb_register failed. Error number %d\n", result);

	return result;
}

static void __exit usb_keyspan_exit(void)
{
	/* deregister this driver with the USB subsystem */
	usb_deregister(&keyspan_driver);
}

module_init(usb_keyspan_init);
module_exit(usb_keyspan_exit);

MODULE_DEVICE_TABLE(usb, keyspan_table);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE(DRIVER_LICENSE);