drivers/input/tablet/wacom_sys.c - kernel/msm-4.19 - Gitiles

 /*
  * drivers/input/tablet/wacom_sys.c
  *
  *  USB Wacom tablet support - system specific code
  */

 /*
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  */

 #include "wacom_wac.h"
 #include "wacom.h"

 /* defines to get HID report descriptor */
 #define HID_DEVICET_HID		(USB_TYPE_CLASS | 0x01)
 #define HID_DEVICET_REPORT	(USB_TYPE_CLASS | 0x02)
 #define HID_USAGE_UNDEFINED		0x00
 #define HID_USAGE_PAGE			0x05
 #define HID_USAGE_PAGE_DIGITIZER	0x0d
 #define HID_USAGE_PAGE_DESKTOP		0x01
 #define HID_USAGE			0x09
 #define HID_USAGE_X			0x30
 #define HID_USAGE_Y			0x31
 #define HID_USAGE_X_TILT		0x3d
 #define HID_USAGE_Y_TILT		0x3e
 #define HID_USAGE_FINGER		0x22
 #define HID_USAGE_STYLUS		0x20
 #define HID_COLLECTION			0xc0

 enum {
 	WCM_UNDEFINED = 0,
 	WCM_DESKTOP,
 	WCM_DIGITIZER,
 };

 struct hid_descriptor {
 	struct usb_descriptor_header header;
 	__le16   bcdHID;
 	u8       bCountryCode;
 	u8       bNumDescriptors;
 	u8       bDescriptorType;
 	__le16   wDescriptorLength;
 } __attribute__ ((packed));

 /* defines to get/set USB message */
 #define USB_REQ_GET_REPORT	0x01
 #define USB_REQ_SET_REPORT	0x09
 #define WAC_HID_FEATURE_REPORT	0x03

 static int usb_get_report(struct usb_interface *intf, unsigned char type,
 				unsigned char id, void *buf, int size)
 {
 	return usb_control_msg(interface_to_usbdev(intf),
 		usb_rcvctrlpipe(interface_to_usbdev(intf), 0),
 		USB_REQ_GET_REPORT, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
 		(type << 8) + id, intf->altsetting[0].desc.bInterfaceNumber,
 		buf, size, 100);
 }

 static int usb_set_report(struct usb_interface *intf, unsigned char type,
 				unsigned char id, void *buf, int size)
 {
 	return usb_control_msg(interface_to_usbdev(intf),
 		usb_sndctrlpipe(interface_to_usbdev(intf), 0),
                 USB_REQ_SET_REPORT, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
                 (type << 8) + id, intf->altsetting[0].desc.bInterfaceNumber,
 		buf, size, 1000);
 }

 static void wacom_sys_irq(struct urb *urb)
 {
 	struct wacom *wacom = urb->context;
 	int retval;

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

 	wacom_wac_irq(&wacom->wacom_wac, urb->actual_length);

  exit:
 	usb_mark_last_busy(wacom->usbdev);
 	retval = usb_submit_urb(urb, GFP_ATOMIC);
 	if (retval)
 		err ("%s - usb_submit_urb failed with result %d",
 		     __func__, retval);
 }

 static int wacom_open(struct input_dev *dev)
 {
 	struct wacom *wacom = input_get_drvdata(dev);

 	mutex_lock(&wacom->lock);

 	wacom->irq->dev = wacom->usbdev;

 	if (usb_autopm_get_interface(wacom->intf) < 0) {
 		mutex_unlock(&wacom->lock);
 		return -EIO;
 	}

 	if (usb_submit_urb(wacom->irq, GFP_KERNEL)) {
 		usb_autopm_put_interface(wacom->intf);
 		mutex_unlock(&wacom->lock);
 		return -EIO;
 	}

 	wacom->open = true;
 	wacom->intf->needs_remote_wakeup = 1;

 	mutex_unlock(&wacom->lock);
 	return 0;
 }

 static void wacom_close(struct input_dev *dev)
 {
 	struct wacom *wacom = input_get_drvdata(dev);

 	mutex_lock(&wacom->lock);
 	usb_kill_urb(wacom->irq);
 	wacom->open = false;
 	wacom->intf->needs_remote_wakeup = 0;
 	mutex_unlock(&wacom->lock);
 }

 static int wacom_parse_hid(struct usb_interface *intf, struct hid_descriptor *hid_desc,
 			   struct wacom_features *features)
 {
 	struct usb_device *dev = interface_to_usbdev(intf);
 	char limit = 0;
 	/* result has to be defined as int for some devices */
 	int result = 0;
 	int i = 0, usage = WCM_UNDEFINED, finger = 0, pen = 0;
 	unsigned char *report;

 	report = kzalloc(hid_desc->wDescriptorLength, GFP_KERNEL);
 	if (!report)
 		return -ENOMEM;

 	/* retrive report descriptors */
 	do {
 		result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 			USB_REQ_GET_DESCRIPTOR,
 			USB_RECIP_INTERFACE | USB_DIR_IN,
 			HID_DEVICET_REPORT << 8,
 			intf->altsetting[0].desc.bInterfaceNumber, /* interface */
 			report,
 			hid_desc->wDescriptorLength,
 			5000); /* 5 secs */
 	} while (result < 0 && limit++ < 5);

 	/* No need to parse the Descriptor. It isn't an error though */
 	if (result < 0)
 		goto out;

 	for (i = 0; i < hid_desc->wDescriptorLength; i++) {

 		switch (report[i]) {
 		case HID_USAGE_PAGE:
 			switch (report[i + 1]) {
 			case HID_USAGE_PAGE_DIGITIZER:
 				usage = WCM_DIGITIZER;
 				i++;
 				break;

 			case HID_USAGE_PAGE_DESKTOP:
 				usage = WCM_DESKTOP;
 				i++;
 				break;
 			}
 			break;

 		case HID_USAGE:
 			switch (report[i + 1]) {
 			case HID_USAGE_X:
 				if (usage == WCM_DESKTOP) {
 					if (finger) {
 						features->device_type = BTN_TOOL_DOUBLETAP;
 						if (features->type == TABLETPC2FG) {
 							/* need to reset back */
 							features->pktlen = WACOM_PKGLEN_TPC2FG;
 							features->device_type = BTN_TOOL_TRIPLETAP;
 						}
 						if (features->type == BAMBOO_PT) {
 							/* need to reset back */
 							features->pktlen = WACOM_PKGLEN_BBTOUCH;
 							features->device_type = BTN_TOOL_TRIPLETAP;
 							features->x_phy =
 								get_unaligned_le16(&report[i + 5]);
 							features->x_max =
 								get_unaligned_le16(&report[i + 8]);
 							i += 15;
 						} else {
 							features->x_max =
 								get_unaligned_le16(&report[i + 3]);
 							features->x_phy =
 								get_unaligned_le16(&report[i + 6]);
 							features->unit = report[i + 9];
 							features->unitExpo = report[i + 11];
 							i += 12;
 						}
 					} else if (pen) {
 						/* penabled only accepts exact bytes of data */
 						if (features->type == TABLETPC2FG)
 							features->pktlen = WACOM_PKGLEN_GRAPHIRE;
 						if (features->type == BAMBOO_PT)
 							features->pktlen = WACOM_PKGLEN_BBFUN;
 						features->device_type = BTN_TOOL_PEN;
 						features->x_max =
 							get_unaligned_le16(&report[i + 3]);
 						i += 4;
 					}
 				} else if (usage == WCM_DIGITIZER) {
 					/* max pressure isn't reported
 					features->pressure_max = (unsigned short)
 							(report[i+4] << 8  | report[i + 3]);
 					*/
 					features->pressure_max = 255;
 					i += 4;
 				}
 				break;

 			case HID_USAGE_Y:
 				if (usage == WCM_DESKTOP) {
 					if (finger) {
 						features->device_type = BTN_TOOL_DOUBLETAP;
 						if (features->type == TABLETPC2FG) {
 							/* need to reset back */
 							features->pktlen = WACOM_PKGLEN_TPC2FG;
 							features->device_type = BTN_TOOL_TRIPLETAP;
 							features->y_max =
 								get_unaligned_le16(&report[i + 3]);
 							features->y_phy =
 								get_unaligned_le16(&report[i + 6]);
 							i += 7;
 						} else if (features->type == BAMBOO_PT) {
 							/* need to reset back */
 							features->pktlen = WACOM_PKGLEN_BBTOUCH;
 							features->device_type = BTN_TOOL_TRIPLETAP;
 							features->y_phy =
 								get_unaligned_le16(&report[i + 3]);
 							features->y_max =
 								get_unaligned_le16(&report[i + 6]);
 							i += 12;
 						} else {
 							features->y_max =
 								features->x_max;
 							features->y_phy =
 								get_unaligned_le16(&report[i + 3]);
 							i += 4;
 						}
 					} else if (pen) {
 						/* penabled only accepts exact bytes of data */
 						if (features->type == TABLETPC2FG)
 							features->pktlen = WACOM_PKGLEN_GRAPHIRE;
 						if (features->type == BAMBOO_PT)
 							features->pktlen = WACOM_PKGLEN_BBFUN;
 						features->device_type = BTN_TOOL_PEN;
 						features->y_max =
 							get_unaligned_le16(&report[i + 3]);
 						i += 4;
 					}
 				}
 				break;

 			case HID_USAGE_FINGER:
 				finger = 1;
 				i++;
 				break;

 			case HID_USAGE_STYLUS:
 				pen = 1;
 				i++;
 				break;

 			case HID_USAGE_UNDEFINED:
 				if (usage == WCM_DESKTOP && finger) /* capacity */
 					features->pressure_max =
 						get_unaligned_le16(&report[i + 3]);
 				i += 4;
 				break;
 			}
 			break;

 		case HID_COLLECTION:
 			/* reset UsagePage and Finger */
 			finger = usage = 0;
 			break;
 		}
 	}

  out:
 	result = 0;
 	kfree(report);
 	return result;
 }

 static int wacom_query_tablet_data(struct usb_interface *intf, struct wacom_features *features)
 {
 	unsigned char *rep_data;
 	int limit = 0, report_id = 2;
 	int error = -ENOMEM;

 	rep_data = kmalloc(2, GFP_KERNEL);
 	if (!rep_data)
 		return error;

 	/* ask to report tablet data if it is 2FGT or not a Tablet PC */
 	if (features->device_type == BTN_TOOL_TRIPLETAP) {
 		do {
 			rep_data[0] = 3;
 			rep_data[1] = 4;
 			report_id = 3;
 			error = usb_set_report(intf, WAC_HID_FEATURE_REPORT,
 				report_id, rep_data, 2);
 			if (error >= 0)
 				error = usb_get_report(intf,
 					WAC_HID_FEATURE_REPORT, report_id,
 					rep_data, 3);
 		} while ((error < 0 || rep_data[1] != 4) && limit++ < 5);
 	} else if (features->type != TABLETPC && features->type != TABLETPC2FG) {
 		do {
 			rep_data[0] = 2;
 			rep_data[1] = 2;
 			error = usb_set_report(intf, WAC_HID_FEATURE_REPORT,
 				report_id, rep_data, 2);
 			if (error >= 0)
 				error = usb_get_report(intf,
 					WAC_HID_FEATURE_REPORT, report_id,
 					rep_data, 2);
 		} while ((error < 0 || rep_data[1] != 2) && limit++ < 5);
 	}

 	kfree(rep_data);

 	return error < 0 ? error : 0;
 }

 static int wacom_retrieve_hid_descriptor(struct usb_interface *intf,
 		struct wacom_features *features)
 {
 	int error = 0;
 	struct usb_host_interface *interface = intf->cur_altsetting;
 	struct hid_descriptor *hid_desc;

 	/* default features */
 	features->device_type = BTN_TOOL_PEN;
 	features->x_fuzz = 4;
 	features->y_fuzz = 4;
 	features->pressure_fuzz = 0;
 	features->distance_fuzz = 0;

 	/* only Tablet PCs need to retrieve the info */
 	if ((features->type != TABLETPC) && (features->type != TABLETPC2FG) &&
 	    (features->type != BAMBOO_PT))
 		goto out;

 	if (usb_get_extra_descriptor(interface, HID_DEVICET_HID, &hid_desc)) {
 		if (usb_get_extra_descriptor(&interface->endpoint[0],
 				HID_DEVICET_REPORT, &hid_desc)) {
 			printk("wacom: can not retrieve extra class descriptor\n");
 			error = 1;
 			goto out;
 		}
 	}
 	error = wacom_parse_hid(intf, hid_desc, features);
 	if (error)
 		goto out;

 	/* touch device found but size is not defined. use default */
 	if (features->device_type == BTN_TOOL_DOUBLETAP && !features->x_max) {
 		features->x_max = 1023;
 		features->y_max = 1023;
 	}

  out:
 	return error;
 }

 struct wacom_usbdev_data {
 	struct list_head list;
 	struct kref kref;
 	struct usb_device *dev;
 	struct wacom_shared shared;
 };

 static LIST_HEAD(wacom_udev_list);
 static DEFINE_MUTEX(wacom_udev_list_lock);

 static struct wacom_usbdev_data *wacom_get_usbdev_data(struct usb_device *dev)
 {
 	struct wacom_usbdev_data *data;

 	list_for_each_entry(data, &wacom_udev_list, list) {
 		if (data->dev == dev) {
 			kref_get(&data->kref);
 			return data;
 		}
 	}

 	return NULL;
 }

 static int wacom_add_shared_data(struct wacom_wac *wacom,
 				 struct usb_device *dev)
 {
 	struct wacom_usbdev_data *data;
 	int retval = 0;

 	mutex_lock(&wacom_udev_list_lock);

 	data = wacom_get_usbdev_data(dev);
 	if (!data) {
 		data = kzalloc(sizeof(struct wacom_usbdev_data), GFP_KERNEL);
 		if (!data) {
 			retval = -ENOMEM;
 			goto out;
 		}

 		kref_init(&data->kref);
 		data->dev = dev;
 		list_add_tail(&data->list, &wacom_udev_list);
 	}

 	wacom->shared = &data->shared;

 out:
 	mutex_unlock(&wacom_udev_list_lock);
 	return retval;
 }

 static void wacom_release_shared_data(struct kref *kref)
 {
 	struct wacom_usbdev_data *data =
 		container_of(kref, struct wacom_usbdev_data, kref);

 	mutex_lock(&wacom_udev_list_lock);
 	list_del(&data->list);
 	mutex_unlock(&wacom_udev_list_lock);

 	kfree(data);
 }

 static void wacom_remove_shared_data(struct wacom_wac *wacom)
 {
 	struct wacom_usbdev_data *data;

 	if (wacom->shared) {
 		data = container_of(wacom->shared, struct wacom_usbdev_data, shared);
 		kref_put(&data->kref, wacom_release_shared_data);
 		wacom->shared = NULL;
 	}
 }

 static int wacom_probe(struct usb_interface *intf, const struct usb_device_id *id)
 {
 	struct usb_device *dev = interface_to_usbdev(intf);
 	struct usb_endpoint_descriptor *endpoint;
 	struct wacom *wacom;
 	struct wacom_wac *wacom_wac;
 	struct wacom_features *features;
 	struct input_dev *input_dev;
 	int error;

 	if (!id->driver_info)
 		return -EINVAL;

 	wacom = kzalloc(sizeof(struct wacom), GFP_KERNEL);
 	input_dev = input_allocate_device();
 	if (!wacom || !input_dev) {
 		error = -ENOMEM;
 		goto fail1;
 	}

 	wacom_wac = &wacom->wacom_wac;
 	wacom_wac->features = *((struct wacom_features *)id->driver_info);
 	features = &wacom_wac->features;
 	if (features->pktlen > WACOM_PKGLEN_MAX) {
 		error = -EINVAL;
 		goto fail1;
 	}

 	wacom_wac->data = usb_alloc_coherent(dev, WACOM_PKGLEN_MAX,
 					     GFP_KERNEL, &wacom->data_dma);
 	if (!wacom_wac->data) {
 		error = -ENOMEM;
 		goto fail1;
 	}

 	wacom->irq = usb_alloc_urb(0, GFP_KERNEL);
 	if (!wacom->irq) {
 		error = -ENOMEM;
 		goto fail2;
 	}

 	wacom->usbdev = dev;
 	wacom->intf = intf;
 	mutex_init(&wacom->lock);
 	usb_make_path(dev, wacom->phys, sizeof(wacom->phys));
 	strlcat(wacom->phys, "/input0", sizeof(wacom->phys));

 	wacom_wac->input = input_dev;

 	endpoint = &intf->cur_altsetting->endpoint[0].desc;

 	/* Retrieve the physical and logical size for OEM devices */
 	error = wacom_retrieve_hid_descriptor(intf, features);
 	if (error)
 		goto fail2;

 	strlcpy(wacom_wac->name, features->name, sizeof(wacom_wac->name));

 	if (features->type == TABLETPC || features->type == TABLETPC2FG ||
 	    features->type == BAMBOO_PT) {
 		/* Append the device type to the name */
 		strlcat(wacom_wac->name,
 			features->device_type == BTN_TOOL_PEN ?
 				" Pen" : " Finger",
 			sizeof(wacom_wac->name));

 		error = wacom_add_shared_data(wacom_wac, dev);
 		if (error)
 			goto fail3;
 	}

 	input_dev->name = wacom_wac->name;
 	input_dev->dev.parent = &intf->dev;
 	input_dev->open = wacom_open;
 	input_dev->close = wacom_close;
 	usb_to_input_id(dev, &input_dev->id);
 	input_set_drvdata(input_dev, wacom);

 	wacom_setup_input_capabilities(input_dev, wacom_wac);

 	usb_fill_int_urb(wacom->irq, dev,
 			 usb_rcvintpipe(dev, endpoint->bEndpointAddress),
 			 wacom_wac->data, features->pktlen,
 			 wacom_sys_irq, wacom, endpoint->bInterval);
 	wacom->irq->transfer_dma = wacom->data_dma;
 	wacom->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

 	error = input_register_device(input_dev);
 	if (error)
 		goto fail4;

 	/* Note that if query fails it is not a hard failure */
 	wacom_query_tablet_data(intf, features);

 	usb_set_intfdata(intf, wacom);
 	return 0;

  fail4:	wacom_remove_shared_data(wacom_wac);
  fail3:	usb_free_urb(wacom->irq);
  fail2:	usb_free_coherent(dev, WACOM_PKGLEN_MAX, wacom_wac->data, wacom->data_dma);
  fail1:	input_free_device(input_dev);
 	kfree(wacom);
 	return error;
 }

 static void wacom_disconnect(struct usb_interface *intf)
 {
 	struct wacom *wacom = usb_get_intfdata(intf);

 	usb_set_intfdata(intf, NULL);

 	usb_kill_urb(wacom->irq);
 	input_unregister_device(wacom->wacom_wac.input);
 	usb_free_urb(wacom->irq);
 	usb_free_coherent(interface_to_usbdev(intf), WACOM_PKGLEN_MAX,
 			wacom->wacom_wac.data, wacom->data_dma);
 	wacom_remove_shared_data(&wacom->wacom_wac);
 	kfree(wacom);
 }

 static int wacom_suspend(struct usb_interface *intf, pm_message_t message)
 {
 	struct wacom *wacom = usb_get_intfdata(intf);

 	mutex_lock(&wacom->lock);
 	usb_kill_urb(wacom->irq);
 	mutex_unlock(&wacom->lock);

 	return 0;
 }

 static int wacom_resume(struct usb_interface *intf)
 {
 	struct wacom *wacom = usb_get_intfdata(intf);
 	struct wacom_features *features = &wacom->wacom_wac.features;
 	int rv;

 	mutex_lock(&wacom->lock);

 	/* switch to wacom mode first */
 	wacom_query_tablet_data(intf, features);

 	if (wacom->open)
 		rv = usb_submit_urb(wacom->irq, GFP_NOIO);
 	else
 		rv = 0;

 	mutex_unlock(&wacom->lock);

 	return rv;
 }

 static int wacom_reset_resume(struct usb_interface *intf)
 {
 	return wacom_resume(intf);
 }

 static struct usb_driver wacom_driver = {
 	.name =		"wacom",
 	.id_table =	wacom_ids,
 	.probe =	wacom_probe,
 	.disconnect =	wacom_disconnect,
 	.suspend =	wacom_suspend,
 	.resume =	wacom_resume,
 	.reset_resume =	wacom_reset_resume,
 	.supports_autosuspend = 1,
 };

 static int __init wacom_init(void)
 {
 	int result;

 	result = usb_register(&wacom_driver);
 	if (result == 0)
 		printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
 		       DRIVER_DESC "\n");
 	return result;
 }

 static void __exit wacom_exit(void)
 {
 	usb_deregister(&wacom_driver);
 }

 module_init(wacom_init);
 module_exit(wacom_exit);
	/*
	* drivers/input/tablet/wacom_sys.c
	*
	* USB Wacom tablet support - system specific code
	*/

	/*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*/

	#include "wacom_wac.h"
	#include "wacom.h"

	/* defines to get HID report descriptor */
	#define HID_DEVICET_HID (USB_TYPE_CLASS \| 0x01)
	#define HID_DEVICET_REPORT (USB_TYPE_CLASS \| 0x02)
	#define HID_USAGE_UNDEFINED 0x00
	#define HID_USAGE_PAGE 0x05
	#define HID_USAGE_PAGE_DIGITIZER 0x0d
	#define HID_USAGE_PAGE_DESKTOP 0x01
	#define HID_USAGE 0x09
	#define HID_USAGE_X 0x30
	#define HID_USAGE_Y 0x31
	#define HID_USAGE_X_TILT 0x3d
	#define HID_USAGE_Y_TILT 0x3e
	#define HID_USAGE_FINGER 0x22
	#define HID_USAGE_STYLUS 0x20
	#define HID_COLLECTION 0xc0

	enum {
	WCM_UNDEFINED = 0,
	WCM_DESKTOP,
	WCM_DIGITIZER,
	};

	struct hid_descriptor {
	struct usb_descriptor_header header;
	__le16 bcdHID;
	u8 bCountryCode;
	u8 bNumDescriptors;
	u8 bDescriptorType;
	__le16 wDescriptorLength;
	} __attribute__ ((packed));

	/* defines to get/set USB message */
	#define USB_REQ_GET_REPORT 0x01
	#define USB_REQ_SET_REPORT 0x09
	#define WAC_HID_FEATURE_REPORT 0x03

	static int usb_get_report(struct usb_interface *intf, unsigned char type,
	unsigned char id, void *buf, int size)
	{
	return usb_control_msg(interface_to_usbdev(intf),
	usb_rcvctrlpipe(interface_to_usbdev(intf), 0),
	USB_REQ_GET_REPORT, USB_TYPE_CLASS \| USB_RECIP_INTERFACE,
	(type << 8) + id, intf->altsetting[0].desc.bInterfaceNumber,
	buf, size, 100);
	}

	static int usb_set_report(struct usb_interface *intf, unsigned char type,
	unsigned char id, void *buf, int size)
	{
	return usb_control_msg(interface_to_usbdev(intf),
	usb_sndctrlpipe(interface_to_usbdev(intf), 0),
	USB_REQ_SET_REPORT, USB_TYPE_CLASS \| USB_RECIP_INTERFACE,
	(type << 8) + id, intf->altsetting[0].desc.bInterfaceNumber,
	buf, size, 1000);
	}

	static void wacom_sys_irq(struct urb *urb)
	{
	struct wacom *wacom = urb->context;
	int retval;

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

	wacom_wac_irq(&wacom->wacom_wac, urb->actual_length);

	exit:
	usb_mark_last_busy(wacom->usbdev);
	retval = usb_submit_urb(urb, GFP_ATOMIC);
	if (retval)
	err ("%s - usb_submit_urb failed with result %d",
	__func__, retval);
	}

	static int wacom_open(struct input_dev *dev)
	{
	struct wacom *wacom = input_get_drvdata(dev);

	mutex_lock(&wacom->lock);

	wacom->irq->dev = wacom->usbdev;

	if (usb_autopm_get_interface(wacom->intf) < 0) {
	mutex_unlock(&wacom->lock);
	return -EIO;
	}

	if (usb_submit_urb(wacom->irq, GFP_KERNEL)) {
	usb_autopm_put_interface(wacom->intf);
	mutex_unlock(&wacom->lock);
	return -EIO;
	}

	wacom->open = true;
	wacom->intf->needs_remote_wakeup = 1;

	mutex_unlock(&wacom->lock);
	return 0;
	}

	static void wacom_close(struct input_dev *dev)
	{
	struct wacom *wacom = input_get_drvdata(dev);

	mutex_lock(&wacom->lock);
	usb_kill_urb(wacom->irq);
	wacom->open = false;
	wacom->intf->needs_remote_wakeup = 0;
	mutex_unlock(&wacom->lock);
	}

	static int wacom_parse_hid(struct usb_interface intf, struct hid_descriptor hid_desc,
	struct wacom_features *features)
	{
	struct usb_device *dev = interface_to_usbdev(intf);
	char limit = 0;
	/* result has to be defined as int for some devices */
	int result = 0;
	int i = 0, usage = WCM_UNDEFINED, finger = 0, pen = 0;
	unsigned char *report;

	report = kzalloc(hid_desc->wDescriptorLength, GFP_KERNEL);
	if (!report)
	return -ENOMEM;

	/* retrive report descriptors */
	do {
	result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
	USB_REQ_GET_DESCRIPTOR,
	USB_RECIP_INTERFACE \| USB_DIR_IN,
	HID_DEVICET_REPORT << 8,
	intf->altsetting[0].desc.bInterfaceNumber, /* interface */
	report,
	hid_desc->wDescriptorLength,
	5000); /* 5 secs */
	} while (result < 0 && limit++ < 5);

	/* No need to parse the Descriptor. It isn't an error though */
	if (result < 0)
	goto out;

	for (i = 0; i < hid_desc->wDescriptorLength; i++) {

	switch (report[i]) {
	case HID_USAGE_PAGE:
	switch (report[i + 1]) {
	case HID_USAGE_PAGE_DIGITIZER:
	usage = WCM_DIGITIZER;
	i++;
	break;

	case HID_USAGE_PAGE_DESKTOP:
	usage = WCM_DESKTOP;
	i++;
	break;
	}
	break;

	case HID_USAGE:
	switch (report[i + 1]) {
	case HID_USAGE_X:
	if (usage == WCM_DESKTOP) {
	if (finger) {
	features->device_type = BTN_TOOL_DOUBLETAP;
	if (features->type == TABLETPC2FG) {
	/* need to reset back */
	features->pktlen = WACOM_PKGLEN_TPC2FG;
	features->device_type = BTN_TOOL_TRIPLETAP;
	}
	if (features->type == BAMBOO_PT) {
	/* need to reset back */
	features->pktlen = WACOM_PKGLEN_BBTOUCH;
	features->device_type = BTN_TOOL_TRIPLETAP;
	features->x_phy =
	get_unaligned_le16(&report[i + 5]);
	features->x_max =
	get_unaligned_le16(&report[i + 8]);
	i += 15;
	} else {
	features->x_max =
	get_unaligned_le16(&report[i + 3]);
	features->x_phy =
	get_unaligned_le16(&report[i + 6]);
	features->unit = report[i + 9];
	features->unitExpo = report[i + 11];
	i += 12;
	}
	} else if (pen) {
	/* penabled only accepts exact bytes of data */
	if (features->type == TABLETPC2FG)
	features->pktlen = WACOM_PKGLEN_GRAPHIRE;
	if (features->type == BAMBOO_PT)
	features->pktlen = WACOM_PKGLEN_BBFUN;
	features->device_type = BTN_TOOL_PEN;
	features->x_max =
	get_unaligned_le16(&report[i + 3]);
	i += 4;
	}
	} else if (usage == WCM_DIGITIZER) {
	/* max pressure isn't reported
	features->pressure_max = (unsigned short)
	(report[i+4] << 8 \| report[i + 3]);
	*/
	features->pressure_max = 255;
	i += 4;
	}
	break;

	case HID_USAGE_Y:
	if (usage == WCM_DESKTOP) {
	if (finger) {
	features->device_type = BTN_TOOL_DOUBLETAP;
	if (features->type == TABLETPC2FG) {
	/* need to reset back */
	features->pktlen = WACOM_PKGLEN_TPC2FG;
	features->device_type = BTN_TOOL_TRIPLETAP;
	features->y_max =
	get_unaligned_le16(&report[i + 3]);
	features->y_phy =
	get_unaligned_le16(&report[i + 6]);
	i += 7;
	} else if (features->type == BAMBOO_PT) {
	/* need to reset back */
	features->pktlen = WACOM_PKGLEN_BBTOUCH;
	features->device_type = BTN_TOOL_TRIPLETAP;
	features->y_phy =
	get_unaligned_le16(&report[i + 3]);
	features->y_max =
	get_unaligned_le16(&report[i + 6]);
	i += 12;
	} else {
	features->y_max =
	features->x_max;
	features->y_phy =
	get_unaligned_le16(&report[i + 3]);
	i += 4;
	}
	} else if (pen) {
	/* penabled only accepts exact bytes of data */
	if (features->type == TABLETPC2FG)
	features->pktlen = WACOM_PKGLEN_GRAPHIRE;
	if (features->type == BAMBOO_PT)
	features->pktlen = WACOM_PKGLEN_BBFUN;
	features->device_type = BTN_TOOL_PEN;
	features->y_max =
	get_unaligned_le16(&report[i + 3]);
	i += 4;
	}
	}
	break;

	case HID_USAGE_FINGER:
	finger = 1;
	i++;
	break;

	case HID_USAGE_STYLUS:
	pen = 1;
	i++;
	break;

	case HID_USAGE_UNDEFINED:
	if (usage == WCM_DESKTOP && finger) /* capacity */
	features->pressure_max =
	get_unaligned_le16(&report[i + 3]);
	i += 4;
	break;
	}
	break;

	case HID_COLLECTION:
	/* reset UsagePage and Finger */
	finger = usage = 0;
	break;
	}
	}

	out:
	result = 0;
	kfree(report);
	return result;
	}

	static int wacom_query_tablet_data(struct usb_interface intf, struct wacom_features features)
	{
	unsigned char *rep_data;
	int limit = 0, report_id = 2;
	int error = -ENOMEM;

	rep_data = kmalloc(2, GFP_KERNEL);
	if (!rep_data)
	return error;

	/* ask to report tablet data if it is 2FGT or not a Tablet PC */
	if (features->device_type == BTN_TOOL_TRIPLETAP) {
	do {
	rep_data[0] = 3;
	rep_data[1] = 4;
	report_id = 3;
	error = usb_set_report(intf, WAC_HID_FEATURE_REPORT,
	report_id, rep_data, 2);
	if (error >= 0)
	error = usb_get_report(intf,
	WAC_HID_FEATURE_REPORT, report_id,
	rep_data, 3);
	} while ((error < 0 \|\| rep_data[1] != 4) && limit++ < 5);
	} else if (features->type != TABLETPC && features->type != TABLETPC2FG) {
	do {
	rep_data[0] = 2;
	rep_data[1] = 2;
	error = usb_set_report(intf, WAC_HID_FEATURE_REPORT,
	report_id, rep_data, 2);
	if (error >= 0)
	error = usb_get_report(intf,
	WAC_HID_FEATURE_REPORT, report_id,
	rep_data, 2);
	} while ((error < 0 \|\| rep_data[1] != 2) && limit++ < 5);
	}

	kfree(rep_data);

	return error < 0 ? error : 0;
	}

	static int wacom_retrieve_hid_descriptor(struct usb_interface *intf,
	struct wacom_features *features)
	{
	int error = 0;
	struct usb_host_interface *interface = intf->cur_altsetting;
	struct hid_descriptor *hid_desc;

	/* default features */
	features->device_type = BTN_TOOL_PEN;
	features->x_fuzz = 4;
	features->y_fuzz = 4;
	features->pressure_fuzz = 0;
	features->distance_fuzz = 0;

	/* only Tablet PCs need to retrieve the info */
	if ((features->type != TABLETPC) && (features->type != TABLETPC2FG) &&
	(features->type != BAMBOO_PT))
	goto out;

	if (usb_get_extra_descriptor(interface, HID_DEVICET_HID, &hid_desc)) {
	if (usb_get_extra_descriptor(&interface->endpoint[0],
	HID_DEVICET_REPORT, &hid_desc)) {
	printk("wacom: can not retrieve extra class descriptor\n");
	error = 1;
	goto out;
	}
	}
	error = wacom_parse_hid(intf, hid_desc, features);
	if (error)
	goto out;

	/* touch device found but size is not defined. use default */
	if (features->device_type == BTN_TOOL_DOUBLETAP && !features->x_max) {
	features->x_max = 1023;
	features->y_max = 1023;
	}

	out:
	return error;
	}

	struct wacom_usbdev_data {
	struct list_head list;
	struct kref kref;
	struct usb_device *dev;
	struct wacom_shared shared;
	};

	static LIST_HEAD(wacom_udev_list);
	static DEFINE_MUTEX(wacom_udev_list_lock);

	static struct wacom_usbdev_data wacom_get_usbdev_data(struct usb_device dev)
	{
	struct wacom_usbdev_data *data;

	list_for_each_entry(data, &wacom_udev_list, list) {
	if (data->dev == dev) {
	kref_get(&data->kref);
	return data;
	}
	}

	return NULL;
	}

	static int wacom_add_shared_data(struct wacom_wac *wacom,
	struct usb_device *dev)
	{
	struct wacom_usbdev_data *data;
	int retval = 0;

	mutex_lock(&wacom_udev_list_lock);

	data = wacom_get_usbdev_data(dev);
	if (!data) {
	data = kzalloc(sizeof(struct wacom_usbdev_data), GFP_KERNEL);
	if (!data) {
	retval = -ENOMEM;
	goto out;
	}

	kref_init(&data->kref);
	data->dev = dev;
	list_add_tail(&data->list, &wacom_udev_list);
	}

	wacom->shared = &data->shared;

	out:
	mutex_unlock(&wacom_udev_list_lock);
	return retval;
	}

	static void wacom_release_shared_data(struct kref *kref)
	{
	struct wacom_usbdev_data *data =
	container_of(kref, struct wacom_usbdev_data, kref);

	mutex_lock(&wacom_udev_list_lock);
	list_del(&data->list);
	mutex_unlock(&wacom_udev_list_lock);

	kfree(data);
	}

	static void wacom_remove_shared_data(struct wacom_wac *wacom)
	{
	struct wacom_usbdev_data *data;

	if (wacom->shared) {
	data = container_of(wacom->shared, struct wacom_usbdev_data, shared);
	kref_put(&data->kref, wacom_release_shared_data);
	wacom->shared = NULL;
	}
	}

	static int wacom_probe(struct usb_interface intf, const struct usb_device_id id)
	{
	struct usb_device *dev = interface_to_usbdev(intf);
	struct usb_endpoint_descriptor *endpoint;
	struct wacom *wacom;
	struct wacom_wac *wacom_wac;
	struct wacom_features *features;
	struct input_dev *input_dev;
	int error;

	if (!id->driver_info)
	return -EINVAL;

	wacom = kzalloc(sizeof(struct wacom), GFP_KERNEL);
	input_dev = input_allocate_device();
	if (!wacom \|\| !input_dev) {
	error = -ENOMEM;
	goto fail1;
	}

	wacom_wac = &wacom->wacom_wac;
	wacom_wac->features = ((struct wacom_features )id->driver_info);
	features = &wacom_wac->features;
	if (features->pktlen > WACOM_PKGLEN_MAX) {
	error = -EINVAL;
	goto fail1;
	}

	wacom_wac->data = usb_alloc_coherent(dev, WACOM_PKGLEN_MAX,
	GFP_KERNEL, &wacom->data_dma);
	if (!wacom_wac->data) {
	error = -ENOMEM;
	goto fail1;
	}

	wacom->irq = usb_alloc_urb(0, GFP_KERNEL);
	if (!wacom->irq) {
	error = -ENOMEM;
	goto fail2;
	}

	wacom->usbdev = dev;
	wacom->intf = intf;
	mutex_init(&wacom->lock);
	usb_make_path(dev, wacom->phys, sizeof(wacom->phys));
	strlcat(wacom->phys, "/input0", sizeof(wacom->phys));

	wacom_wac->input = input_dev;

	endpoint = &intf->cur_altsetting->endpoint[0].desc;

	/* Retrieve the physical and logical size for OEM devices */
	error = wacom_retrieve_hid_descriptor(intf, features);
	if (error)
	goto fail2;

	strlcpy(wacom_wac->name, features->name, sizeof(wacom_wac->name));

	if (features->type == TABLETPC \|\| features->type == TABLETPC2FG \|\|
	features->type == BAMBOO_PT) {
	/* Append the device type to the name */
	strlcat(wacom_wac->name,
	features->device_type == BTN_TOOL_PEN ?
	" Pen" : " Finger",
	sizeof(wacom_wac->name));

	error = wacom_add_shared_data(wacom_wac, dev);
	if (error)
	goto fail3;
	}

	input_dev->name = wacom_wac->name;
	input_dev->dev.parent = &intf->dev;
	input_dev->open = wacom_open;
	input_dev->close = wacom_close;
	usb_to_input_id(dev, &input_dev->id);
	input_set_drvdata(input_dev, wacom);

	wacom_setup_input_capabilities(input_dev, wacom_wac);

	usb_fill_int_urb(wacom->irq, dev,
	usb_rcvintpipe(dev, endpoint->bEndpointAddress),
	wacom_wac->data, features->pktlen,
	wacom_sys_irq, wacom, endpoint->bInterval);
	wacom->irq->transfer_dma = wacom->data_dma;
	wacom->irq->transfer_flags \|= URB_NO_TRANSFER_DMA_MAP;

	error = input_register_device(input_dev);
	if (error)
	goto fail4;

	/* Note that if query fails it is not a hard failure */
	wacom_query_tablet_data(intf, features);

	usb_set_intfdata(intf, wacom);
	return 0;

	fail4: wacom_remove_shared_data(wacom_wac);
	fail3: usb_free_urb(wacom->irq);
	fail2: usb_free_coherent(dev, WACOM_PKGLEN_MAX, wacom_wac->data, wacom->data_dma);
	fail1: input_free_device(input_dev);
	kfree(wacom);
	return error;
	}

	static void wacom_disconnect(struct usb_interface *intf)
	{
	struct wacom *wacom = usb_get_intfdata(intf);

	usb_set_intfdata(intf, NULL);

	usb_kill_urb(wacom->irq);
	input_unregister_device(wacom->wacom_wac.input);
	usb_free_urb(wacom->irq);
	usb_free_coherent(interface_to_usbdev(intf), WACOM_PKGLEN_MAX,
	wacom->wacom_wac.data, wacom->data_dma);
	wacom_remove_shared_data(&wacom->wacom_wac);
	kfree(wacom);
	}

	static int wacom_suspend(struct usb_interface *intf, pm_message_t message)
	{
	struct wacom *wacom = usb_get_intfdata(intf);

	mutex_lock(&wacom->lock);
	usb_kill_urb(wacom->irq);
	mutex_unlock(&wacom->lock);

	return 0;
	}

	static int wacom_resume(struct usb_interface *intf)
	{
	struct wacom *wacom = usb_get_intfdata(intf);
	struct wacom_features *features = &wacom->wacom_wac.features;
	int rv;

	mutex_lock(&wacom->lock);

	/* switch to wacom mode first */
	wacom_query_tablet_data(intf, features);

	if (wacom->open)
	rv = usb_submit_urb(wacom->irq, GFP_NOIO);
	else
	rv = 0;

	mutex_unlock(&wacom->lock);

	return rv;
	}

	static int wacom_reset_resume(struct usb_interface *intf)
	{
	return wacom_resume(intf);
	}

	static struct usb_driver wacom_driver = {
	.name = "wacom",
	.id_table = wacom_ids,
	.probe = wacom_probe,
	.disconnect = wacom_disconnect,
	.suspend = wacom_suspend,
	.resume = wacom_resume,
	.reset_resume = wacom_reset_resume,
	.supports_autosuspend = 1,
	};

	static int __init wacom_init(void)
	{
	int result;

	result = usb_register(&wacom_driver);
	if (result == 0)
	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
	DRIVER_DESC "\n");
	return result;
	}

	static void __exit wacom_exit(void)
	{
	usb_deregister(&wacom_driver);
	}

	module_init(wacom_init);
	module_exit(wacom_exit);