text: // SPDX-License-Identifier: GPL-2.0-or-later
  /*
   * drivers/input/tablet/wacom_sys.c
   *
   *  USB Wacom tablet support - system specific code
   */
  
  /*
   */
  
  #include "wacom_wac.h"
  #include "wacom.h"
  #include <linux/input/mt.h>
  
  #define WAC_MSG_RETRIES		5
  #define WAC_CMD_RETRIES		10
  
  #define DEV_ATTR_RW_PERM (S_IRUGO | S_IWUSR | S_IWGRP)
  #define DEV_ATTR_WO_PERM (S_IWUSR | S_IWGRP)
  #define DEV_ATTR_RO_PERM (S_IRUSR | S_IRGRP)
  
  static int wacom_get_report(struct hid_device *hdev, u8 type, u8 *buf,
  			    size_t size, unsigned int retries)
  {
  	int retval;
  
  	do {
  		retval = hid_hw_raw_request(hdev, buf[0], buf, size, type,
  				HID_REQ_GET_REPORT);
  	} while ((retval == -ETIMEDOUT || retval == -EAGAIN) && --retries);
  
  	if (retval < 0)
  		hid_err(hdev, "wacom_get_report: ran out of retries "
  			"(last error = %d)\n", retval);
  
  	return retval;
  }
  
  static int wacom_set_report(struct hid_device *hdev, u8 type, u8 *buf,
  			    size_t size, unsigned int retries)
  {
  	int retval;
  
  	do {
  		retval = hid_hw_raw_request(hdev, buf[0], buf, size, type,
  				HID_REQ_SET_REPORT);
  	} while ((retval == -ETIMEDOUT || retval == -EAGAIN) && --retries);
  
  	if (retval < 0)
  		hid_err(hdev, "wacom_set_report: ran out of retries "
  			"(last error = %d)\n", retval);
  
  	return retval;
  }
  
  static void wacom_wac_queue_insert(struct hid_device *hdev,
  				   struct kfifo_rec_ptr_2 *fifo,
  				   u8 *raw_data, int size)
  {
  	bool warned = false;
  
  	while (kfifo_avail(fifo) < size) {
  		if (!warned)
  			hid_warn(hdev, "%s: kfifo has filled, starting to drop events\n", __func__);
  		warned = true;
  
  		kfifo_skip(fifo);
  	}
  
  	kfifo_in(fifo, raw_data, size);
  }
  
  static void wacom_wac_queue_flush(struct hid_device *hdev,
  				  struct kfifo_rec_ptr_2 *fifo)
  {
  	while (!kfifo_is_empty(fifo)) {
  		u8 buf[WACOM_PKGLEN_MAX];
  		int size;
  		int err;
  
  		size = kfifo_out(fifo, buf, sizeof(buf));
  		err = hid_report_raw_event(hdev, HID_INPUT_REPORT, buf, size, false);
  		if (err) {
  			hid_warn(hdev, "%s: unable to flush event due to error %d\n",
  				 __func__, err);
  		}
  	}
  }
  
  static int wacom_wac_pen_serial_enforce(struct hid_device *hdev,
  		struct hid_report *report, u8 *raw_data, int report_size)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
  	struct wacom_features *features = &wacom_wac->features;
  	bool flush = false;
  	bool insert = false;
  	int i, j;
  
  	if (wacom_wac->serial[0] || !(features->quirks & WACOM_QUIRK_TOOLSERIAL))
  		return 0;
  
  	/* Queue events which have invalid tool type or serial number */
  	for (i = 0; i < report->maxfield; i++) {
  		for (j = 0; j < report->field[i]->maxusage; j++) {
  			struct hid_field *field = report->field[i];
  			struct hid_usage *usage = &field->usage[j];
  			unsigned int equivalent_usage = wacom_equivalent_usage(usage->hid);
  			unsigned int offset;
  			unsigned int size;
  			unsigned int value;
  
  			if (equivalent_usage != HID_DG_INRANGE &&
  			    equivalent_usage != HID_DG_TOOLSERIALNUMBER &&
  			    equivalent_usage != WACOM_HID_WD_SERIALHI &&
  			    equivalent_usage != WACOM_HID_WD_TOOLTYPE)
  				continue;
  
  			offset = field->report_offset;
  			size = field->report_size;
  			value = hid_field_extract(hdev, raw_data+1, offset + j * size, size);
  
  			/* If we go out of range, we need to flush the queue ASAP */
  			if (equivalent_usage == HID_DG_INRANGE)
  				value = !value;
  
  			if (value) {
  				flush = true;
  				switch (equivalent_usage) {
  				case HID_DG_TOOLSERIALNUMBER:
  					wacom_wac->serial[0] = value;
  					break;
  
  				case WACOM_HID_WD_SERIALHI:
  					wacom_wac->serial[0] |= ((__u64)value) << 32;
  					break;
  
  				case WACOM_HID_WD_TOOLTYPE:
  					wacom_wac->id[0] = value;
  					break;
  				}
  			}
  			else {
  				insert = true;
  			}
  		}
  	}
  
  	if (flush)
  		wacom_wac_queue_flush(hdev, &wacom_wac->pen_fifo);
  	else if (insert)
  		wacom_wac_queue_insert(hdev, &wacom_wac->pen_fifo,
  				       raw_data, report_size);
  
  	return insert && !flush;
  }
  
  static int wacom_raw_event(struct hid_device *hdev, struct hid_report *report,
  		u8 *raw_data, int size)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  
  	if (size > WACOM_PKGLEN_MAX)
  		return 1;
  
  	if (wacom_wac_pen_serial_enforce(hdev, report, raw_data, size))
  		return -1;
  
  	memcpy(wacom->wacom_wac.data, raw_data, size);
  
  	wacom_wac_irq(&wacom->wacom_wac, size);
  
  	return 0;
  }
  
  static int wacom_open(struct input_dev *dev)
  {
  	struct wacom *wacom = input_get_drvdata(dev);
  
  	return hid_hw_open(wacom->hdev);
  }
  
  static void wacom_close(struct input_dev *dev)
  {
  	struct wacom *wacom = input_get_drvdata(dev);
  
  	/*
  	 * wacom->hdev should never be null, but surprisingly, I had the case
  	 * once while unplugging the Wacom Wireless Receiver.
  	 */
  	if (wacom->hdev)
  		hid_hw_close(wacom->hdev);
  }
  
  /*
   * Calculate the resolution of the X or Y axis using hidinput_calc_abs_res.
   */
  static int wacom_calc_hid_res(int logical_extents, int physical_extents,
  			       unsigned unit, int exponent)
  {
  	struct hid_field field = {
  		.logical_maximum = logical_extents,
  		.physical_maximum = physical_extents,
  		.unit = unit,
  		.unit_exponent = exponent,
  	};
  
  	return hidinput_calc_abs_res(&field, ABS_X);
  }
  
  static void wacom_hid_usage_quirk(struct hid_device *hdev,
  		struct hid_field *field, struct hid_usage *usage)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	struct wacom_features *features = &wacom->wacom_wac.features;
  	unsigned int equivalent_usage = wacom_equivalent_usage(usage->hid);
  
  	/*
  	 * The Dell Canvas 27 needs to be switched to its vendor-defined
  	 * report to provide the best resolution.
  	 */
  	if (hdev->vendor == USB_VENDOR_ID_WACOM &&
  	    hdev->product == 0x4200 &&
  	    field->application == HID_UP_MSVENDOR) {
  		wacom->wacom_wac.mode_report = field->report->id;
  		wacom->wacom_wac.mode_value = 2;
  	}
  
  	/*
  	 * ISDv4 devices which predate HID's adoption of the
  	 * HID_DG_BARELSWITCH2 usage use 0x000D0000 in its
  	 * position instead. We can accurately detect if a
  	 * usage with that value should be HID_DG_BARRELSWITCH2
  	 * based on the surrounding usages, which have remained
  	 * constant across generations.
  	 */
  	if (features->type == HID_GENERIC &&
  	    usage->hid == 0x000D0000 &&
  	    field->application == HID_DG_PEN &&
  	    field->physical == HID_DG_STYLUS) {
  		int i = usage->usage_index;
  
  		if (i-4 >= 0 && i+1 < field->maxusage &&
  		    field->usage[i-4].hid == HID_DG_TIPSWITCH &&
  		    field->usage[i-3].hid == HID_DG_BARRELSWITCH &&
  		    field->usage[i-2].hid == HID_DG_ERASER &&
  		    field->usage[i-1].hid == HID_DG_INVERT &&
  		    field->usage[i+1].hid == HID_DG_INRANGE) {
  			usage->hid = HID_DG_BARRELSWITCH2;
  		}
  	}
  
  	/*
  	 * Wacom's AES devices use different vendor-defined usages to
  	 * report serial number information compared to their branded
  	 * hardware. The usages are also sometimes ill-defined and do
  	 * not have the correct logical min/max values set. Lets patch
  	 * the descriptor to use the branded usage convention and fix
  	 * the errors.
  	 */
  	if (usage->hid == WACOM_HID_WT_SERIALNUMBER &&
  	    field->report_size == 16 &&
  	    field->index + 2 < field->report->maxfield) {
  		struct hid_field *a = field->report->field[field->index + 1];
  		struct hid_field *b = field->report->field[field->index + 2];
  
  		if (a->maxusage > 0 &&
  		    a->usage[0].hid == HID_DG_TOOLSERIALNUMBER &&
  		    a->report_size == 32 &&
  		    b->maxusage > 0 &&
  		    b->usage[0].hid == 0xFF000000 &&
  		    b->report_size == 8) {
  			features->quirks |= WACOM_QUIRK_AESPEN;
  			usage->hid = WACOM_HID_WD_TOOLTYPE;
  			field->logical_minimum = S16_MIN;
  			field->logical_maximum = S16_MAX;
  			a->logical_minimum = S32_MIN;
  			a->logical_maximum = S32_MAX;
  			b->usage[0].hid = WACOM_HID_WD_SERIALHI;
  			b->logical_minimum = 0;
  			b->logical_maximum = U8_MAX;
  		}
  	}
  
  	/* 2nd-generation Intuos Pro Large has incorrect Y maximum */
  	if (hdev->vendor == USB_VENDOR_ID_WACOM &&
  	    hdev->product == 0x0358 &&
  	    WACOM_PEN_FIELD(field) &&
  	    equivalent_usage == HID_GD_Y) {
  		field->logical_maximum = 43200;
  	}
  }
  
  static void wacom_feature_mapping(struct hid_device *hdev,
  		struct hid_field *field, struct hid_usage *usage)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	struct wacom_features *features = &wacom->wacom_wac.features;
  	struct hid_data *hid_data = &wacom->wacom_wac.hid_data;
  	unsigned int equivalent_usage = wacom_equivalent_usage(usage->hid);
  	u8 *data;
  	int ret;
  	u32 n;
  
  	wacom_hid_usage_quirk(hdev, field, usage);
  
  	switch (equivalent_usage) {
  	case WACOM_HID_WD_TOUCH_RING_SETTING:
  		wacom->generic_has_leds = true;
  		break;
  	case HID_DG_CONTACTMAX:
  		/* leave touch_max as is if predefined */
  		if (!features->touch_max) {
  			/* read manually */
  			n = hid_report_len(field->report);
  			data = hid_alloc_report_buf(field->report, GFP_KERNEL);
  			if (!data)
  				break;
  			data[0] = field->report->id;
  			ret = wacom_get_report(hdev, HID_FEATURE_REPORT,
  					       data, n, WAC_CMD_RETRIES);
  			if (ret == n && features->type == HID_GENERIC) {
  				ret = hid_report_raw_event(hdev,
  					HID_FEATURE_REPORT, data, n, 0);
  			} else if (ret == 2 && features->type != HID_GENERIC) {
  				features->touch_max = data[1];
  			} else {
  				features->touch_max = 16;
  				hid_warn(hdev, "wacom_feature_mapping: "
  					 "could not get HID_DG_CONTACTMAX, "
  					 "defaulting to %d\n",
  					  features->touch_max);
  			}
  			kfree(data);
  		}
  		break;
  	case HID_DG_INPUTMODE:
  		/* Ignore if value index is out of bounds. */
  		if (usage->usage_index >= field->report_count) {
  			dev_err(&hdev->dev, "HID_DG_INPUTMODE out of range\n");
  			break;
  		}
  
  		hid_data->inputmode = field->report->id;
  		hid_data->inputmode_index = usage->usage_index;
  		break;
  
  	case HID_UP_DIGITIZER:
  		if (field->report->id == 0x0B &&
  		    (field->application == WACOM_HID_G9_PEN ||
  		     field->application == WACOM_HID_G11_PEN)) {
  			wacom->wacom_wac.mode_report = field->report->id;
  			wacom->wacom_wac.mode_value = 0;
  		}
  		break;
  
  	case WACOM_HID_WD_DATAMODE:
  		wacom->wacom_wac.mode_report = field->report->id;
  		wacom->wacom_wac.mode_value = 2;
  		break;
  
  	case WACOM_HID_UP_G9:
  	case WACOM_HID_UP_G11:
  		if (field->report->id == 0x03 &&
  		    (field->application == WACOM_HID_G9_TOUCHSCREEN ||
  		     field->application == WACOM_HID_G11_TOUCHSCREEN)) {
  			wacom->wacom_wac.mode_report = field->report->id;
  			wacom->wacom_wac.mode_value = 0;
  		}
  		break;
  	case WACOM_HID_WD_OFFSETLEFT:
  	case WACOM_HID_WD_OFFSETTOP:
  	case WACOM_HID_WD_OFFSETRIGHT:
  	case WACOM_HID_WD_OFFSETBOTTOM:
  		/* read manually */
  		n = hid_report_len(field->report);
  		data = hid_alloc_report_buf(field->report, GFP_KERNEL);
  		if (!data)
  			break;
  		data[0] = field->report->id;
  		ret = wacom_get_report(hdev, HID_FEATURE_REPORT,
  					data, n, WAC_CMD_RETRIES);
  		if (ret == n) {
  			ret = hid_report_raw_event(hdev, HID_FEATURE_REPORT,
  						   data, n, 0);
  		} else {
  			hid_warn(hdev, "%s: could not retrieve sensor offsets\n",
  				 __func__);
  		}
  		kfree(data);
  		break;
  	}
  }
  
  /*
   * Interface Descriptor of wacom devices can be incomplete and
   * inconsistent so wacom_features table is used to store stylus
   * device's packet lengths, various maximum values, and tablet
   * resolution based on product ID's.
   *
   * For devices that contain 2 interfaces, wacom_features table is
   * inaccurate for the touch interface.  Since the Interface Descriptor
   * for touch interfaces has pretty complete data, this function exists
   * to query tablet for this missing information instead of hard coding in
   * an additional table.
   *
   * A typical Interface Descriptor for a stylus will contain a
   * boot mouse application collection that is not of interest and this
   * function will ignore it.
   *
   * It also contains a digitizer application collection that also is not
   * of interest since any information it contains would be duplicate
   * of what is in wacom_features. Usually it defines a report of an array
   * of bytes that could be used as max length of the stylus packet returned.
   * If it happens to define a Digitizer-Stylus Physical Collection then
   * the X and Y logical values contain valid data but it is ignored.
   *
   * A typical Interface Descriptor for a touch interface will contain a
   * Digitizer-Finger Physical Collection which will define both logical
   * X/Y maximum as well as the physical size of tablet. Since touch
   * interfaces haven't supported pressure or distance, this is enough
   * information to override invalid values in the wacom_features table.
   *
   * Intuos5 touch interface and 3rd gen Bamboo Touch do not contain useful
   * data. We deal with them after returning from this function.
   */
  static void wacom_usage_mapping(struct hid_device *hdev,
  		struct hid_field *field, struct hid_usage *usage)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	struct wacom_features *features = &wacom->wacom_wac.features;
  	bool finger = WACOM_FINGER_FIELD(field);
  	bool pen = WACOM_PEN_FIELD(field);
  	unsigned equivalent_usage = wacom_equivalent_usage(usage->hid);
  
  	/*
  	* Requiring Stylus Usage will ignore boot mouse
  	* X/Y values and some cases of invalid Digitizer X/Y
  	* values commonly reported.
  	*/
  	if (pen)
  		features->device_type |= WACOM_DEVICETYPE_PEN;
  	else if (finger)
  		features->device_type |= WACOM_DEVICETYPE_TOUCH;
  	else
  		return;
  
  	wacom_hid_usage_quirk(hdev, field, usage);
  
  	switch (equivalent_usage) {
  	case HID_GD_X:
  		features->x_max = field->logical_maximum;
  		if (finger) {
  			features->x_phy = field->physical_maximum;
  			if ((features->type != BAMBOO_PT) &&
  			    (features->type != BAMBOO_TOUCH)) {
  				features->unit = field->unit;
  				features->unitExpo = field->unit_exponent;
  			}
  		}
  		break;
  	case HID_GD_Y:
  		features->y_max = field->logical_maximum;
  		if (finger) {
  			features->y_phy = field->physical_maximum;
  			if ((features->type != BAMBOO_PT) &&
  			    (features->type != BAMBOO_TOUCH)) {
  				features->unit = field->unit;
  				features->unitExpo = field->unit_exponent;
  			}
  		}
  		break;
  	case HID_DG_TIPPRESSURE:
  		if (pen)
  			features->pressure_max = field->logical_maximum;
  		break;
  	}
  
  	if (features->type == HID_GENERIC)
  		wacom_wac_usage_mapping(hdev, field, usage);
  }
  
  static void wacom_post_parse_hid(struct hid_device *hdev,
  				 struct wacom_features *features)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
  
  	if (features->type == HID_GENERIC) {
  		/* Any last-minute generic device setup */
  		if (wacom_wac->has_mode_change) {
  			if (wacom_wac->is_direct_mode)
  				features->device_type |= WACOM_DEVICETYPE_DIRECT;
  			else
  				features->device_type &= ~WACOM_DEVICETYPE_DIRECT;
  		}
  
  		if (features->touch_max > 1) {
  			if (features->device_type & WACOM_DEVICETYPE_DIRECT)
  				input_mt_init_slots(wacom_wac->touch_input,
  						    wacom_wac->features.touch_max,
  						    INPUT_MT_DIRECT);
  			else
  				input_mt_init_slots(wacom_wac->touch_input,
  						    wacom_wac->features.touch_max,
  						    INPUT_MT_POINTER);
  		}
  	}
  }
  
  static void wacom_parse_hid(struct hid_device *hdev,
  			   struct wacom_features *features)
  {
  	struct hid_report_enum *rep_enum;
  	struct hid_report *hreport;
  	int i, j;
  
  	/* check features first */
  	rep_enum = &hdev->report_enum[HID_FEATURE_REPORT];
  	list_for_each_entry(hreport, &rep_enum->report_list, list) {
  		for (i = 0; i < hreport->maxfield; i++) {
  			/* Ignore if report count is out of bounds. */
  			if (hreport->field[i]->report_count < 1)
  				continue;
  
  			for (j = 0; j < hreport->field[i]->maxusage; j++) {
  				wacom_feature_mapping(hdev, hreport->field[i],
  						hreport->field[i]->usage + j);
  			}
  		}
  	}
  
  	/* now check the input usages */
  	rep_enum = &hdev->report_enum[HID_INPUT_REPORT];
  	list_for_each_entry(hreport, &rep_enum->report_list, list) {
  
  		if (!hreport->maxfield)
  			continue;
  
  		for (i = 0; i < hreport->maxfield; i++)
  			for (j = 0; j < hreport->field[i]->maxusage; j++)
  				wacom_usage_mapping(hdev, hreport->field[i],
  						hreport->field[i]->usage + j);
  	}
  
  	wacom_post_parse_hid(hdev, features);
  }
  
  static int wacom_hid_set_device_mode(struct hid_device *hdev)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	struct hid_data *hid_data = &wacom->wacom_wac.hid_data;
  	struct hid_report *r;
  	struct hid_report_enum *re;
  
  	if (hid_data->inputmode < 0)
  		return 0;
  
  	re = &(hdev->report_enum[HID_FEATURE_REPORT]);
  	r = re->report_id_hash[hid_data->inputmode];
  	if (r) {
  		r->field[0]->value[hid_data->inputmode_index] = 2;
  		hid_hw_request(hdev, r, HID_REQ_SET_REPORT);
  	}
  	return 0;
  }
  
  static int wacom_set_device_mode(struct hid_device *hdev,
  				 struct wacom_wac *wacom_wac)
  {
  	u8 *rep_data;
  	struct hid_report *r;
  	struct hid_report_enum *re;
  	u32 length;
  	int error = -ENOMEM, limit = 0;
  
  	if (wacom_wac->mode_report < 0)
  		return 0;
  
  	re = &(hdev->report_enum[HID_FEATURE_REPORT]);
  	r = re->report_id_hash[wacom_wac->mode_report];
  	if (!r)
  		return -EINVAL;
  
  	rep_data = hid_alloc_report_buf(r, GFP_KERNEL);
  	if (!rep_data)
  		return -ENOMEM;
  
  	length = hid_report_len(r);
  
  	do {
  		rep_data[0] = wacom_wac->mode_report;
  		rep_data[1] = wacom_wac->mode_value;
  
  		error = wacom_set_report(hdev, HID_FEATURE_REPORT, rep_data,
  					 length, 1);
  		if (error >= 0)
  			error = wacom_get_report(hdev, HID_FEATURE_REPORT,
  			                         rep_data, length, 1);
  	} while (error >= 0 &&
  		 rep_data[1] != wacom_wac->mode_report &&
  		 limit++ < WAC_MSG_RETRIES);
  
  	kfree(rep_data);
  
  	return error < 0 ? error : 0;
  }
  
  static int wacom_bt_query_tablet_data(struct hid_device *hdev, u8 speed,
  		struct wacom_features *features)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	int ret;
  	u8 rep_data[2];
  
  	switch (features->type) {
  	case GRAPHIRE_BT:
  		rep_data[0] = 0x03;
  		rep_data[1] = 0x00;
  		ret = wacom_set_report(hdev, HID_FEATURE_REPORT, rep_data, 2,
  					3);
  
  		if (ret >= 0) {
  			rep_data[0] = speed == 0 ? 0x05 : 0x06;
  			rep_data[1] = 0x00;
  
  			ret = wacom_set_report(hdev, HID_FEATURE_REPORT,
  						rep_data, 2, 3);
  
  			if (ret >= 0) {
  				wacom->wacom_wac.bt_high_speed = speed;
  				return 0;
  			}
  		}
  
  		/*
  		 * Note that if the raw queries fail, it's not a hard failure
  		 * and it is safe to continue
  		 */
  		hid_warn(hdev, "failed to poke device, command %d, err %d\n",
  			 rep_data[0], ret);
  		break;
  	case INTUOS4WL:
  		if (speed == 1)
  			wacom->wacom_wac.bt_features &= ~0x20;
  		else
  			wacom->wacom_wac.bt_features |= 0x20;
  
  		rep_data[0] = 0x03;
  		rep_data[1] = wacom->wacom_wac.bt_features;
  
  		ret = wacom_set_report(hdev, HID_FEATURE_REPORT, rep_data, 2,
  					1);
  		if (ret >= 0)
  			wacom->wacom_wac.bt_high_speed = speed;
  		break;
  	}
  
  	return 0;
  }
  
  /*
   * Switch the tablet into its most-capable mode. Wacom tablets are
   * typically configured to power-up in a mode which sends mouse-like
   * reports to the OS. To get absolute position, pressure data, etc.
   * from the tablet, it is necessary to switch the tablet out of this
   * mode and into one which sends the full range of tablet data.
   */
  static int _wacom_query_tablet_data(struct wacom *wacom)
  {
  	struct hid_device *hdev = wacom->hdev;
  	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
  	struct wacom_features *features = &wacom_wac->features;
  
  	if (hdev->bus == BUS_BLUETOOTH)
  		return wacom_bt_query_tablet_data(hdev, 1, features);
  
  	if (features->type != HID_GENERIC) {
  		if (features->device_type & WACOM_DEVICETYPE_TOUCH) {
  			if (features->type > TABLETPC) {
  				/* MT Tablet PC touch */
  				wacom_wac->mode_report = 3;
  				wacom_wac->mode_value = 4;
  			} else if (features->type == WACOM_24HDT) {
  				wacom_wac->mode_report = 18;
  				wacom_wac->mode_value = 2;
  			} else if (features->type == WACOM_27QHDT) {
  				wacom_wac->mode_report = 131;
  				wacom_wac->mode_value = 2;
  			} else if (features->type == BAMBOO_PAD) {
  				wacom_wac->mode_report = 2;
  				wacom_wac->mode_value = 2;
  			}
  		} else if (features->device_type & WACOM_DEVICETYPE_PEN) {
  			if (features->type <= BAMBOO_PT) {
  				wacom_wac->mode_report = 2;
  				wacom_wac->mode_value = 2;
  			}
  		}
  	}
  
  	wacom_set_device_mode(hdev, wacom_wac);
  
  	if (features->type == HID_GENERIC)
  		return wacom_hid_set_device_mode(hdev);
  
  	return 0;
  }
  
  static void wacom_retrieve_hid_descriptor(struct hid_device *hdev,
  					 struct wacom_features *features)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	struct usb_interface *intf = wacom->intf;
  
  	/* default features */
  	features->x_fuzz = 4;
  	features->y_fuzz = 4;
  	features->pressure_fuzz = 0;
  	features->distance_fuzz = 1;
  	features->tilt_fuzz = 1;
  
  	/*
  	 * The wireless device HID is basic and layout conflicts with
  	 * other tablets (monitor and touch interface can look like pen).
  	 * Skip the query for this type and modify defaults based on
  	 * interface number.
  	 */
  	if (features->type == WIRELESS) {
  		if (intf->cur_altsetting->desc.bInterfaceNumber == 0)
  			features->device_type = WACOM_DEVICETYPE_WL_MONITOR;
  		else
  			features->device_type = WACOM_DEVICETYPE_NONE;
  		return;
  	}
  
  	wacom_parse_hid(hdev, features);
  }
  
  struct wacom_hdev_data {
  	struct list_head list;
  	struct kref kref;
  	struct hid_device *dev;
  	struct wacom_shared shared;
  };
  
  static LIST_HEAD(wacom_udev_list);
  static DEFINE_MUTEX(wacom_udev_list_lock);
  
  static bool wacom_are_sibling(struct hid_device *hdev,
  		struct hid_device *sibling)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	struct wacom_features *features = &wacom->wacom_wac.features;
  	struct wacom *sibling_wacom = hid_get_drvdata(sibling);
  	struct wacom_features *sibling_features = &sibling_wacom->wacom_wac.features;
  	__u32 oVid = features->oVid ? features->oVid : hdev->vendor;
  	__u32 oPid = features->oPid ? features->oPid : hdev->product;
  
  	/* The defined oVid/oPid must match that of the sibling */
  	if (features->oVid != HID_ANY_ID && sibling->vendor != oVid)
  		return false;
  	if (features->oPid != HID_ANY_ID && sibling->product != oPid)
  		return false;
  
  	/*
  	 * Devices with the same VID/PID must share the same physical
  	 * device path, while those with different VID/PID must share
  	 * the same physical parent device path.
  	 */
  	if (hdev->vendor == sibling->vendor && hdev->product == sibling->product) {
  		if (!hid_compare_device_paths(hdev, sibling, '/'))
  			return false;
  	} else {
  		if (!hid_compare_device_paths(hdev, sibling, '.'))
  			return false;
  	}
  
  	/* Skip the remaining heuristics unless you are a HID_GENERIC device */
  	if (features->type != HID_GENERIC)
  		return true;
  
  	/*
  	 * Direct-input devices may not be siblings of indirect-input
  	 * devices.
  	 */
  	if ((features->device_type & WACOM_DEVICETYPE_DIRECT) &&
  	    !(sibling_features->device_type & WACOM_DEVICETYPE_DIRECT))
  		return false;
  
  	/*
  	 * Indirect-input devices may not be siblings of direct-input
  	 * devices.
  	 */
  	if (!(features->device_type & WACOM_DEVICETYPE_DIRECT) &&
  	    (sibling_features->device_type & WACOM_DEVICETYPE_DIRECT))
  		return false;
  
  	/* Pen devices may only be siblings of touch devices */
  	if ((features->device_type & WACOM_DEVICETYPE_PEN) &&
  	    !(sibling_features->device_type & WACOM_DEVICETYPE_TOUCH))
  		return false;
  
  	/* Touch devices may only be siblings of pen devices */
  	if ((features->device_type & WACOM_DEVICETYPE_TOUCH) &&
  	    !(sibling_features->device_type & WACOM_DEVICETYPE_PEN))
  		return false;
  
  	/*
  	 * No reason could be found for these two devices to NOT be
  	 * siblings, so there's a good chance they ARE siblings
  	 */
  	return true;
  }
  
  static struct wacom_hdev_data *wacom_get_hdev_data(struct hid_device *hdev)
  {
  	struct wacom_hdev_data *data;
  
  	/* Try to find an already-probed interface from the same device */
  	list_for_each_entry(data, &wacom_udev_list, list) {
  		if (hid_compare_device_paths(hdev, data->dev, '/')) {
  			kref_get(&data->kref);
  			return data;
  		}
  	}
  
  	/* Fallback to finding devices that appear to be "siblings" */
  	list_for_each_entry(data, &wacom_udev_list, list) {
  		if (wacom_are_sibling(hdev, data->dev)) {
  			kref_get(&data->kref);
  			return data;
  		}
  	}
  
  	return NULL;
  }
  
  static void wacom_release_shared_data(struct kref *kref)
  {
  	struct wacom_hdev_data *data =
  		container_of(kref, struct wacom_hdev_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(void *res)
  {
  	struct wacom *wacom = res;
  	struct wacom_hdev_data *data;
  	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
  
  	if (wacom_wac->shared) {
  		data = container_of(wacom_wac->shared, struct wacom_hdev_data,
  				    shared);
  
  		if (wacom_wac->shared->touch == wacom->hdev)
  			wacom_wac->shared->touch = NULL;
  		else if (wacom_wac->shared->pen == wacom->hdev)
  			wacom_wac->shared->pen = NULL;
  
  		kref_put(&data->kref, wacom_release_shared_data);
  		wacom_wac->shared = NULL;
  	}
  }
  
  static int wacom_add_shared_data(struct hid_device *hdev)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
  	struct wacom_hdev_data *data;
  	int retval = 0;
  
  	mutex_lock(&wacom_udev_list_lock);
  
  	data = wacom_get_hdev_data(hdev);
  	if (!data) {
  		data = kzalloc(sizeof(struct wacom_hdev_data), GFP_KERNEL);
  		if (!data) {
  			retval = -ENOMEM;
  			goto out;
  		}
  
  		kref_init(&data->kref);
  		data->dev = hdev;
  		list_add_tail(&data->list, &wacom_udev_list);
  	}
  
  	wacom_wac->shared = &data->shared;
  
  	retval = devm_add_action(&hdev->dev, wacom_remove_shared_data, wacom);
  	if (retval) {
  		mutex_unlock(&wacom_udev_list_lock);
  		wacom_remove_shared_data(wacom);
  		return retval;
  	}
  
  	if (wacom_wac->features.device_type & WACOM_DEVICETYPE_TOUCH)
  		wacom_wac->shared->touch = hdev;
  	else if (wacom_wac->features.device_type & WACOM_DEVICETYPE_PEN)
  		wacom_wac->shared->pen = hdev;
  
  out:
  	mutex_unlock(&wacom_udev_list_lock);
  	return retval;
  }
  
  static int wacom_led_control(struct wacom *wacom)
  {
  	unsigned char *buf;
  	int retval;
  	unsigned char report_id = WAC_CMD_LED_CONTROL;
  	int buf_size = 9;
  
  	if (!wacom->led.groups)
  		return -ENOTSUPP;
  
  	if (wacom->wacom_wac.features.type == REMOTE)
  		return -ENOTSUPP;
  
  	if (wacom->wacom_wac.pid) { /* wireless connected */
  		report_id = WAC_CMD_WL_LED_CONTROL;
  		buf_size = 13;
  	}
  	else if (wacom->wacom_wac.features.type == INTUOSP2_BT) {
  		report_id = WAC_CMD_WL_INTUOSP2;
  		buf_size = 51;
  	}
  	buf = kzalloc(buf_size, GFP_KERNEL);
  	if (!buf)
  		return -ENOMEM;
  
  	if (wacom->wacom_wac.features.type == HID_GENERIC) {
  		buf[0] = WAC_CMD_LED_CONTROL_GENERIC;
  		buf[1] = wacom->led.llv;
  		buf[2] = wacom->led.groups[0].select & 0x03;
  
  	} else if ((wacom->wacom_wac.features.type >= INTUOS5S &&
  	    wacom->wacom_wac.features.type <= INTUOSPL)) {
  		/*
  		 * Touch Ring and crop mark LED luminance may take on
  		 * one of four values:
  		 *    0 = Low; 1 = Medium; 2 = High; 3 = Off
  		 */
  		int ring_led = wacom->led.groups[0].select & 0x03;
  		int ring_lum = (((wacom->led.llv & 0x60) >> 5) - 1) & 0x03;
  		int crop_lum = 0;
  		unsigned char led_bits = (crop_lum << 4) | (ring_lum << 2) | (ring_led);
  
  		buf[0] = report_id;
  		if (wacom->wacom_wac.pid) {
  			wacom_get_report(wacom->hdev, HID_FEATURE_REPORT,
  					 buf, buf_size, WAC_CMD_RETRIES);
  			buf[0] = report_id;
  			buf[4] = led_bits;
  		} else
  			buf[1] = led_bits;
  	}
  	else if (wacom->wacom_wac.features.type == INTUOSP2_BT) {
  		buf[0] = report_id;
  		buf[4] = 100; // Power Connection LED (ORANGE)
  		buf[5] = 100; // BT Connection LED (BLUE)
  		buf[6] = 100; // Paper Mode (RED?)
  		buf[7] = 100; // Paper Mode (GREEN?)
  		buf[8] = 100; // Paper Mode (BLUE?)
  		buf[9] = wacom->led.llv;
  		buf[10] = wacom->led.groups[0].select & 0x03;
  	}
  	else {
  		int led = wacom->led.groups[0].select | 0x4;
  
  		if (wacom->wacom_wac.features.type == WACOM_21UX2 ||
  		    wacom->wacom_wac.features.type == WACOM_24HD)
  			led |= (wacom->led.groups[1].select << 4) | 0x40;
  
  		buf[0] = report_id;
  		buf[1] = led;
  		buf[2] = wacom->led.llv;
  		buf[3] = wacom->led.hlv;
  		buf[4] = wacom->led.img_lum;
  	}
  
  	retval = wacom_set_report(wacom->hdev, HID_FEATURE_REPORT, buf, buf_size,
  				  WAC_CMD_RETRIES);
  	kfree(buf);
  
  	return retval;
  }
  
  static int wacom_led_putimage(struct wacom *wacom, int button_id, u8 xfer_id,
  		const unsigned len, const void *img)
  {
  	unsigned char *buf;
  	int i, retval;
  	const unsigned chunk_len = len / 4; /* 4 chunks are needed to be sent */
  
  	buf = kzalloc(chunk_len + 3 , GFP_KERNEL);
  	if (!buf)
  		return -ENOMEM;
  
  	/* Send 'start' command */
  	buf[0] = WAC_CMD_ICON_START;
  	buf[1] = 1;
  	retval = wacom_set_report(wacom->hdev, HID_FEATURE_REPORT, buf, 2,
  				  WAC_CMD_RETRIES);
  	if (retval < 0)
  		goto out;
  
  	buf[0] = xfer_id;
  	buf[1] = button_id & 0x07;
  	for (i = 0; i < 4; i++) {
  		buf[2] = i;
  		memcpy(buf + 3, img + i * chunk_len, chunk_len);
  
  		retval = wacom_set_report(wacom->hdev, HID_FEATURE_REPORT,
  					  buf, chunk_len + 3, WAC_CMD_RETRIES);
  		if (retval < 0)
  			break;
  	}
  
  	/* Send 'stop' */
  	buf[0] = WAC_CMD_ICON_START;
  	buf[1] = 0;
  	wacom_set_report(wacom->hdev, HID_FEATURE_REPORT, buf, 2,
  			 WAC_CMD_RETRIES);
  
  out:
  	kfree(buf);
  	return retval;
  }
  
  static ssize_t wacom_led_select_store(struct device *dev, int set_id,
  				      const char *buf, size_t count)
  {
  	struct hid_device *hdev = to_hid_device(dev);
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	unsigned int id;
  	int err;
  
  	err = kstrtouint(buf, 10, &id);
  	if (err)
  		return err;
  
  	mutex_lock(&wacom->lock);
  
  	wacom->led.groups[set_id].select = id & 0x3;
  	err = wacom_led_control(wacom);
  
  	mutex_unlock(&wacom->lock);
  
  	return err < 0 ? err : count;
  }
  
  #define DEVICE_LED_SELECT_ATTR(SET_ID)					\
  static ssize_t wacom_led##SET_ID##_select_store(struct device *dev,	\
  	struct device_attribute *attr, const char *buf, size_t count)	\
  {									\
  	return wacom_led_select_store(dev, SET_ID, buf, count);		\
  }									\
  static ssize_t wacom_led##SET_ID##_select_show(struct device *dev,	\
  	struct device_attribute *attr, char *buf)			\
  {									\
  	struct hid_device *hdev = to_hid_device(dev);\
  	struct wacom *wacom = hid_get_drvdata(hdev);			\
  	return scnprintf(buf, PAGE_SIZE, "%d\n",			\
  			 wacom->led.groups[SET_ID].select);		\
  }									\
  static DEVICE_ATTR(status_led##SET_ID##_select, DEV_ATTR_RW_PERM,	\
  		    wacom_led##SET_ID##_select_show,			\
  		    wacom_led##SET_ID##_select_store)
  
  DEVICE_LED_SELECT_ATTR(0);
  DEVICE_LED_SELECT_ATTR(1);
  
  static ssize_t wacom_luminance_store(struct wacom *wacom, u8 *dest,
  				     const char *buf, size_t count)
  {
  	unsigned int value;
  	int err;
  
  	err = kstrtouint(buf, 10, &value);
  	if (err)
  		return err;
  
  	mutex_lock(&wacom->lock);
  
  	*dest = value & 0x7f;
  	err = wacom_led_control(wacom);
  
  	mutex_unlock(&wacom->lock);
  
  	return err < 0 ? err : count;
  }
  
  #define DEVICE_LUMINANCE_ATTR(name, field)				\
  static ssize_t wacom_##name##_luminance_store(struct device *dev,	\
  	struct device_attribute *attr, const char *buf, size_t count)	\
  {									\
  	struct hid_device *hdev = to_hid_device(dev);\
  	struct wacom *wacom = hid_get_drvdata(hdev);			\
  									\
  	return wacom_luminance_store(wacom, &wacom->led.field,		\
  				     buf, count);			\
  }									\
  static ssize_t wacom_##name##_luminance_show(struct device *dev,	\
  	struct device_attribute *attr, char *buf)			\
  {									\
  	struct wacom *wacom = dev_get_drvdata(dev);			\
  	return scnprintf(buf, PAGE_SIZE, "%d\n", wacom->led.field);	\
  }									\
  static DEVICE_ATTR(name##_luminance, DEV_ATTR_RW_PERM,			\
  		   wacom_##name##_luminance_show,			\
  		   wacom_##name##_luminance_store)
  
  DEVICE_LUMINANCE_ATTR(status0, llv);
  DEVICE_LUMINANCE_ATTR(status1, hlv);
  DEVICE_LUMINANCE_ATTR(buttons, img_lum);
  
  static ssize_t wacom_button_image_store(struct device *dev, int button_id,
  					const char *buf, size_t count)
  {
  	struct hid_device *hdev = to_hid_device(dev);
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	int err;
  	unsigned len;
  	u8 xfer_id;
  
  	if (hdev->bus == BUS_BLUETOOTH) {
  		len = 256;
  		xfer_id = WAC_CMD_ICON_BT_XFER;
  	} else {
  		len = 1024;
  		xfer_id = WAC_CMD_ICON_XFER;
  	}
  
  	if (count != len)
  		return -EINVAL;
  
  	mutex_lock(&wacom->lock);
  
  	err = wacom_led_putimage(wacom, button_id, xfer_id, len, buf);
  
  	mutex_unlock(&wacom->lock);
  
  	return err < 0 ? err : count;
  }
  
  #define DEVICE_BTNIMG_ATTR(BUTTON_ID)					\
  static ssize_t wacom_btnimg##BUTTON_ID##_store(struct device *dev,	\
  	struct device_attribute *attr, const char *buf, size_t count)	\
  {									\
  	return wacom_button_image_store(dev, BUTTON_ID, buf, count);	\
  }									\
  static DEVICE_ATTR(button##BUTTON_ID##_rawimg, DEV_ATTR_WO_PERM,	\
  		   NULL, wacom_btnimg##BUTTON_ID##_store)
  
  DEVICE_BTNIMG_ATTR(0);
  DEVICE_BTNIMG_ATTR(1);
  DEVICE_BTNIMG_ATTR(2);
  DEVICE_BTNIMG_ATTR(3);
  DEVICE_BTNIMG_ATTR(4);
  DEVICE_BTNIMG_ATTR(5);
  DEVICE_BTNIMG_ATTR(6);
  DEVICE_BTNIMG_ATTR(7);
  
  static struct attribute *cintiq_led_attrs[] = {
  	&dev_attr_status_led0_select.attr,
  	&dev_attr_status_led1_select.attr,
  	NULL
  };
  
  static struct attribute_group cintiq_led_attr_group = {
  	.name = "wacom_led",
  	.attrs = cintiq_led_attrs,
  };
  
  static struct attribute *intuos4_led_attrs[] = {
  	&dev_attr_status0_luminance.attr,
  	&dev_attr_status1_luminance.attr,
  	&dev_attr_status_led0_select.attr,
  	&dev_attr_buttons_luminance.attr,
  	&dev_attr_button0_rawimg.attr,
  	&dev_attr_button1_rawimg.attr,
  	&dev_attr_button2_rawimg.attr,
  	&dev_attr_button3_rawimg.attr,
  	&dev_attr_button4_rawimg.attr,
  	&dev_attr_button5_rawimg.attr,
  	&dev_attr_button6_rawimg.attr,
  	&dev_attr_button7_rawimg.attr,
  	NULL
  };
  
  static struct attribute_group intuos4_led_attr_group = {
  	.name = "wacom_led",
  	.attrs = intuos4_led_attrs,
  };
  
  static struct attribute *intuos5_led_attrs[] = {
  	&dev_attr_status0_luminance.attr,
  	&dev_attr_status_led0_select.attr,
  	NULL
  };
  
  static struct attribute_group intuos5_led_attr_group = {
  	.name = "wacom_led",
  	.attrs = intuos5_led_attrs,
  };
  
  static struct attribute *generic_led_attrs[] = {
  	&dev_attr_status0_luminance.attr,
  	&dev_attr_status_led0_select.attr,
  	NULL
  };
  
  static struct attribute_group generic_led_attr_group = {
  	.name = "wacom_led",
  	.attrs = generic_led_attrs,
  };
  
  struct wacom_sysfs_group_devres {
  	struct attribute_group *group;
  	struct kobject *root;
  };
  
  static void wacom_devm_sysfs_group_release(struct device *dev, void *res)
  {
  	struct wacom_sysfs_group_devres *devres = res;
  	struct kobject *kobj = devres->root;
  
  	dev_dbg(dev, "%s: dropping reference to %s\n",
  		__func__, devres->group->name);
  	sysfs_remove_group(kobj, devres->group);
  }
  
  static int __wacom_devm_sysfs_create_group(struct wacom *wacom,
  					   struct kobject *root,
  					   struct attribute_group *group)
  {
  	struct wacom_sysfs_group_devres *devres;
  	int error;
  
  	devres = devres_alloc(wacom_devm_sysfs_group_release,
  			      sizeof(struct wacom_sysfs_group_devres),
  			      GFP_KERNEL);
  	if (!devres)
  		return -ENOMEM;
  
  	devres->group = group;
  	devres->root = root;
  
  	error = sysfs_create_group(devres->root, group);
  	if (error) {
  		devres_free(devres);
  		return error;
  	}
  
  	devres_add(&wacom->hdev->dev, devres);
  
  	return 0;
  }
  
  static int wacom_devm_sysfs_create_group(struct wacom *wacom,
  					 struct attribute_group *group)
  {
  	return __wacom_devm_sysfs_create_group(wacom, &wacom->hdev->dev.kobj,
  					       group);
  }
  
  enum led_brightness wacom_leds_brightness_get(struct wacom_led *led)
  {
  	struct wacom *wacom = led->wacom;
  
  	if (wacom->led.max_hlv)
  		return led->hlv * LED_FULL / wacom->led.max_hlv;
  
  	if (wacom->led.max_llv)
  		return led->llv * LED_FULL / wacom->led.max_llv;
  
  	/* device doesn't support brightness tuning */
  	return LED_FULL;
  }
  
  static enum led_brightness __wacom_led_brightness_get(struct led_classdev *cdev)
  {
  	struct wacom_led *led = container_of(cdev, struct wacom_led, cdev);
  	struct wacom *wacom = led->wacom;
  
  	if (wacom->led.groups[led->group].select != led->id)
  		return LED_OFF;
  
  	return wacom_leds_brightness_get(led);
  }
  
  static int wacom_led_brightness_set(struct led_classdev *cdev,
  				    enum led_brightness brightness)
  {
  	struct wacom_led *led = container_of(cdev, struct wacom_led, cdev);
  	struct wacom *wacom = led->wacom;
  	int error;
  
  	mutex_lock(&wacom->lock);
  
  	if (!wacom->led.groups || (brightness == LED_OFF &&
  	    wacom->led.groups[led->group].select != led->id)) {
  		error = 0;
  		goto out;
  	}
  
  	led->llv = wacom->led.llv = wacom->led.max_llv * brightness / LED_FULL;
  	led->hlv = wacom->led.hlv = wacom->led.max_hlv * brightness / LED_FULL;
  
  	wacom->led.groups[led->group].select = led->id;
  
  	error = wacom_led_control(wacom);
  
  out:
  	mutex_unlock(&wacom->lock);
  
  	return error;
  }
  
  static void wacom_led_readonly_brightness_set(struct led_classdev *cdev,
  					       enum led_brightness brightness)
  {
  }
  
  static int wacom_led_register_one(struct device *dev, struct wacom *wacom,
  				  struct wacom_led *led, unsigned int group,
  				  unsigned int id, bool read_only)
  {
  	int error;
  	char *name;
  
  	name = devm_kasprintf(dev, GFP_KERNEL,
  			      "%s::wacom-%d.%d",
  			      dev_name(dev),
  			      group,
  			      id);
  	if (!name)
  		return -ENOMEM;
  
  	if (!read_only) {
  		led->trigger.name = name;
  		error = devm_led_trigger_register(dev, &led->trigger);
  		if (error) {
  			hid_err(wacom->hdev,
  				"failed to register LED trigger %s: %d\n",
  				led->cdev.name, error);
  			return error;
  		}
  	}
  
  	led->group = group;
  	led->id = id;
  	led->wacom = wacom;
  	led->llv = wacom->led.llv;
  	led->hlv = wacom->led.hlv;
  	led->cdev.name = name;
  	led->cdev.max_brightness = LED_FULL;
  	led->cdev.flags = LED_HW_PLUGGABLE;
  	led->cdev.brightness_get = __wacom_led_brightness_get;
  	if (!read_only) {
  		led->cdev.brightness_set_blocking = wacom_led_brightness_set;
  		led->cdev.default_trigger = led->cdev.name;
  	} else {
  		led->cdev.brightness_set = wacom_led_readonly_brightness_set;
  	}
  
  	error = devm_led_classdev_register(dev, &led->cdev);
  	if (error) {
  		hid_err(wacom->hdev,
  			"failed to register LED %s: %d\n",
  			led->cdev.name, error);
  		led->cdev.name = NULL;
  		return error;
  	}
  
  	return 0;
  }
  
  static void wacom_led_groups_release_one(void *data)
  {
  	struct wacom_group_leds *group = data;
  
  	devres_release_group(group->dev, group);
  }
  
  static int wacom_led_groups_alloc_and_register_one(struct device *dev,
  						   struct wacom *wacom,
  						   int group_id, int count,
  						   bool read_only)
  {
  	struct wacom_led *leds;
  	int i, error;
  
  	if (group_id >= wacom->led.count || count <= 0)
  		return -EINVAL;
  
  	if (!devres_open_group(dev, &wacom->led.groups[group_id], GFP_KERNEL))
  		return -ENOMEM;
  
  	leds = devm_kcalloc(dev, count, sizeof(struct wacom_led), GFP_KERNEL);
  	if (!leds) {
  		error = -ENOMEM;
  		goto err;
  	}
  
  	wacom->led.groups[group_id].leds = leds;
  	wacom->led.groups[group_id].count = count;
  
  	for (i = 0; i < count; i++) {
  		error = wacom_led_register_one(dev, wacom, &leds[i],
  					       group_id, i, read_only);
  		if (error)
  			goto err;
  	}
  
  	wacom->led.groups[group_id].dev = dev;
  
  	devres_close_group(dev, &wacom->led.groups[group_id]);
  
  	/*
  	 * There is a bug (?) in devm_led_classdev_register() in which its
  	 * increments the refcount of the parent. If the parent is an input
  	 * device, that means the ref count never reaches 0 when
  	 * devm_input_device_release() gets called.
  	 * This means that the LEDs are still there after disconnect.
  	 * Manually force the release of the group so that the leds are released
  	 * once we are done using them.
  	 */
  	error = devm_add_action_or_reset(&wacom->hdev->dev,
  					 wacom_led_groups_release_one,
  					 &wacom->led.groups[group_id]);
  	if (error)
  		return error;
  
  	return 0;
  
  err:
  	devres_release_group(dev, &wacom->led.groups[group_id]);
  	return error;
  }
  
  struct wacom_led *wacom_led_find(struct wacom *wacom, unsigned int group_id,
  				 unsigned int id)
  {
  	struct wacom_group_leds *group;
  
  	if (group_id >= wacom->led.count)
  		return NULL;
  
  	group = &wacom->led.groups[group_id];
  
  	if (!group->leds)
  		return NULL;
  
  	id %= group->count;
  
  	return &group->leds[id];
  }
  
  /**
   * wacom_led_next: gives the next available led with a wacom trigger.
   *
   * returns the next available struct wacom_led which has its default trigger
   * or the current one if none is available.
   */
  struct wacom_led *wacom_led_next(struct wacom *wacom, struct wacom_led *cur)
  {
  	struct wacom_led *next_led;
  	int group, next;
  
  	if (!wacom || !cur)
  		return NULL;
  
  	group = cur->group;
  	next = cur->id;
  
  	do {
  		next_led = wacom_led_find(wacom, group, ++next);
  		if (!next_led || next_led == cur)
  			return next_led;
  	} while (next_led->cdev.trigger != &next_led->trigger);
  
  	return next_led;
  }
  
  static void wacom_led_groups_release(void *data)
  {
  	struct wacom *wacom = data;
  
  	wacom->led.groups = NULL;
  	wacom->led.count = 0;
  }
  
  static int wacom_led_groups_allocate(struct wacom *wacom, int count)
  {
  	struct device *dev = &wacom->hdev->dev;
  	struct wacom_group_leds *groups;
  	int error;
  
  	groups = devm_kcalloc(dev, count, sizeof(struct wacom_group_leds),
  			      GFP_KERNEL);
  	if (!groups)
  		return -ENOMEM;
  
  	error = devm_add_action_or_reset(dev, wacom_led_groups_release, wacom);
  	if (error)
  		return error;
  
  	wacom->led.groups = groups;
  	wacom->led.count = count;
  
  	return 0;
  }
  
  static int wacom_leds_alloc_and_register(struct wacom *wacom, int group_count,
  					 int led_per_group, bool read_only)
  {
  	struct device *dev;
  	int i, error;
  
  	if (!wacom->wacom_wac.pad_input)
  		return -EINVAL;
  
  	dev = &wacom->wacom_wac.pad_input->dev;
  
  	error = wacom_led_groups_allocate(wacom, group_count);
  	if (error)
  		return error;
  
  	for (i = 0; i < group_count; i++) {
  		error = wacom_led_groups_alloc_and_register_one(dev, wacom, i,
  								led_per_group,
  								read_only);
  		if (error)
  			return error;
  	}
  
  	return 0;
  }
  
  int wacom_initialize_leds(struct wacom *wacom)
  {
  	int error;
  
  	if (!(wacom->wacom_wac.features.device_type & WACOM_DEVICETYPE_PAD))
  		return 0;
  
  	/* Initialize default values */
  	switch (wacom->wacom_wac.features.type) {
  	case HID_GENERIC:
  		if (!wacom->generic_has_leds)
  			return 0;
  		wacom->led.llv = 100;
  		wacom->led.max_llv = 100;
  
  		error = wacom_leds_alloc_and_register(wacom, 1, 4, false);
  		if (error) {
  			hid_err(wacom->hdev,
  				"cannot create leds err: %d\n", error);
  			return error;
  		}
  
  		error = wacom_devm_sysfs_create_group(wacom,
  						      &generic_led_attr_group);
  		break;
  
  	case INTUOS4S:
  	case INTUOS4:
  	case INTUOS4WL:
  	case INTUOS4L:
  		wacom->led.llv = 10;
  		wacom->led.hlv = 20;
  		wacom->led.max_llv = 127;
  		wacom->led.max_hlv = 127;
  		wacom->led.img_lum = 10;
  
  		error = wacom_leds_alloc_and_register(wacom, 1, 4, false);
  		if (error) {
  			hid_err(wacom->hdev,
  				"cannot create leds err: %d\n", error);
  			return error;
  		}
  
  		error = wacom_devm_sysfs_create_group(wacom,
  						      &intuos4_led_attr_group);
  		break;
  
  	case WACOM_24HD:
  	case WACOM_21UX2:
  		wacom->led.llv = 0;
  		wacom->led.hlv = 0;
  		wacom->led.img_lum = 0;
  
  		error = wacom_leds_alloc_and_register(wacom, 2, 4, false);
  		if (error) {
  			hid_err(wacom->hdev,
  				"cannot create leds err: %d\n", error);
  			return error;
  		}
  
  		error = wacom_devm_sysfs_create_group(wacom,
  						      &cintiq_led_attr_group);
  		break;
  
  	case INTUOS5S:
  	case INTUOS5:
  	case INTUOS5L:
  	case INTUOSPS:
  	case INTUOSPM:
  	case INTUOSPL:
  		wacom->led.llv = 32;
  		wacom->led.max_llv = 96;
  
  		error = wacom_leds_alloc_and_register(wacom, 1, 4, false);
  		if (error) {
  			hid_err(wacom->hdev,
  				"cannot create leds err: %d\n", error);
  			return error;
  		}
  
  		error = wacom_devm_sysfs_create_group(wacom,
  						      &intuos5_led_attr_group);
  		break;
  
  	case INTUOSP2_BT:
  		wacom->led.llv = 50;
  		wacom->led.max_llv = 100;
  		error = wacom_leds_alloc_and_register(wacom, 1, 4, false);
  		if (error) {
  			hid_err(wacom->hdev,
  				"cannot create leds err: %d\n", error);
  			return error;
  		}
  		return 0;
  
  	case REMOTE:
  		wacom->led.llv = 255;
  		wacom->led.max_llv = 255;
  		error = wacom_led_groups_allocate(wacom, 5);
  		if (error) {
  			hid_err(wacom->hdev,
  				"cannot create leds err: %d\n", error);
  			return error;
  		}
  		return 0;
  
  	default:
  		return 0;
  	}
  
  	if (error) {
  		hid_err(wacom->hdev,
  			"cannot create sysfs group err: %d\n", error);
  		return error;
  	}
  
  	return 0;
  }
  
  static void wacom_init_work(struct work_struct *work)
  {
  	struct wacom *wacom = container_of(work, struct wacom, init_work.work);
  
  	_wacom_query_tablet_data(wacom);
  	wacom_led_control(wacom);
  }
  
  static void wacom_query_tablet_data(struct wacom *wacom)
  {
  	schedule_delayed_work(&wacom->init_work, msecs_to_jiffies(1000));
  }
  
  static enum power_supply_property wacom_battery_props[] = {
  	POWER_SUPPLY_PROP_MODEL_NAME,
  	POWER_SUPPLY_PROP_PRESENT,
  	POWER_SUPPLY_PROP_STATUS,
  	POWER_SUPPLY_PROP_SCOPE,
  	POWER_SUPPLY_PROP_CAPACITY
  };
  
  static int wacom_battery_get_property(struct power_supply *psy,
  				      enum power_supply_property psp,
  				      union power_supply_propval *val)
  {
  	struct wacom_battery *battery = power_supply_get_drvdata(psy);
  	int ret = 0;
  
  	switch (psp) {
  		case POWER_SUPPLY_PROP_MODEL_NAME:
  			val->strval = battery->wacom->wacom_wac.name;
  			break;
  		case POWER_SUPPLY_PROP_PRESENT:
  			val->intval = battery->bat_connected;
  			break;
  		case POWER_SUPPLY_PROP_SCOPE:
  			val->intval = POWER_SUPPLY_SCOPE_DEVICE;
  			break;
  		case POWER_SUPPLY_PROP_CAPACITY:
  			val->intval = battery->battery_capacity;
  			break;
  		case POWER_SUPPLY_PROP_STATUS:
  			if (battery->bat_status != WACOM_POWER_SUPPLY_STATUS_AUTO)
  				val->intval = battery->bat_status;
  			else if (battery->bat_charging)
  				val->intval = POWER_SUPPLY_STATUS_CHARGING;
  			else if (battery->battery_capacity == 100 &&
  				    battery->ps_connected)
  				val->intval = POWER_SUPPLY_STATUS_FULL;
  			else if (battery->ps_connected)
  				val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
  			else
  				val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
  			break;
  		default:
  			ret = -EINVAL;
  			break;
  	}
  
  	return ret;
  }
  
  static int __wacom_initialize_battery(struct wacom *wacom,
  				      struct wacom_battery *battery)
  {
  	static atomic_t battery_no = ATOMIC_INIT(0);
  	struct device *dev = &wacom->hdev->dev;
  	struct power_supply_config psy_cfg = { .drv_data = battery, };
  	struct power_supply *ps_bat;
  	struct power_supply_desc *bat_desc = &battery->bat_desc;
  	unsigned long n;
  	int error;
  
  	if (!devres_open_group(dev, bat_desc, GFP_KERNEL))
  		return -ENOMEM;
  
  	battery->wacom = wacom;
  
  	n = atomic_inc_return(&battery_no) - 1;
  
  	bat_desc->properties = wacom_battery_props;
  	bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
  	bat_desc->get_property = wacom_battery_get_property;
  	sprintf(battery->bat_name, "wacom_battery_%ld", n);
  	bat_desc->name = battery->bat_name;
  	bat_desc->type = POWER_SUPPLY_TYPE_USB;
  	bat_desc->use_for_apm = 0;
  
  	ps_bat = devm_power_supply_register(dev, bat_desc, &psy_cfg);
  	if (IS_ERR(ps_bat)) {
  		error = PTR_ERR(ps_bat);
  		goto err;
  	}
  
  	power_supply_powers(ps_bat, &wacom->hdev->dev);
  
  	battery->battery = ps_bat;
  
  	devres_close_group(dev, bat_desc);
  	return 0;
  
  err:
  	devres_release_group(dev, bat_desc);
  	return error;
  }
  
  static int wacom_initialize_battery(struct wacom *wacom)
  {
  	if (wacom->wacom_wac.features.quirks & WACOM_QUIRK_BATTERY)
  		return __wacom_initialize_battery(wacom, &wacom->battery);
  
  	return 0;
  }
  
  static void wacom_destroy_battery(struct wacom *wacom)
  {
  	if (wacom->battery.battery) {
  		devres_release_group(&wacom->hdev->dev,
  				     &wacom->battery.bat_desc);
  		wacom->battery.battery = NULL;
  	}
  }
  
  static ssize_t wacom_show_speed(struct device *dev,
  				struct device_attribute
  				*attr, char *buf)
  {
  	struct hid_device *hdev = to_hid_device(dev);
  	struct wacom *wacom = hid_get_drvdata(hdev);
  
  	return snprintf(buf, PAGE_SIZE, "%i\n", wacom->wacom_wac.bt_high_speed);
  }
  
  static ssize_t wacom_store_speed(struct device *dev,
  				struct device_attribute *attr,
  				const char *buf, size_t count)
  {
  	struct hid_device *hdev = to_hid_device(dev);
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	u8 new_speed;
  
  	if (kstrtou8(buf, 0, &new_speed))
  		return -EINVAL;
  
  	if (new_speed != 0 && new_speed != 1)
  		return -EINVAL;
  
  	wacom_bt_query_tablet_data(hdev, new_speed, &wacom->wacom_wac.features);
  
  	return count;
  }
  
  static DEVICE_ATTR(speed, DEV_ATTR_RW_PERM,
  		wacom_show_speed, wacom_store_speed);
  
  
  static ssize_t wacom_show_remote_mode(struct kobject *kobj,
  				      struct kobj_attribute *kattr,
  				      char *buf, int index)
  {
  	struct device *dev = kobj_to_dev(kobj->parent);
  	struct hid_device *hdev = to_hid_device(dev);
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	u8 mode;
  
  	mode = wacom->led.groups[index].select;
  	return sprintf(buf, "%d\n", mode < 3 ? mode : -1);
  }
  
  #define DEVICE_EKR_ATTR_GROUP(SET_ID)					\
  static ssize_t wacom_show_remote##SET_ID##_mode(struct kobject *kobj,	\
  			       struct kobj_attribute *kattr, char *buf)	\
  {									\
  	return wacom_show_remote_mode(kobj, kattr, buf, SET_ID);	\
  }									\
  static struct kobj_attribute remote##SET_ID##_mode_attr = {		\
  	.attr = {.name = "remote_mode",					\
  		.mode = DEV_ATTR_RO_PERM},				\
  	.show = wacom_show_remote##SET_ID##_mode,			\
  };									\
  static struct attribute *remote##SET_ID##_serial_attrs[] = {		\
  	&remote##SET_ID##_mode_attr.attr,				\
  	NULL								\
  };									\
  static struct attribute_group remote##SET_ID##_serial_group = {		\
  	.name = NULL,							\
  	.attrs = remote##SET_ID##_serial_attrs,				\
  }
  
  DEVICE_EKR_ATTR_GROUP(0);
  DEVICE_EKR_ATTR_GROUP(1);
  DEVICE_EKR_ATTR_GROUP(2);
  DEVICE_EKR_ATTR_GROUP(3);
  DEVICE_EKR_ATTR_GROUP(4);
  
  static int wacom_remote_create_attr_group(struct wacom *wacom, __u32 serial,
  					  int index)
  {
  	int error = 0;
  	struct wacom_remote *remote = wacom->remote;
  
  	remote->remotes[index].group.name = devm_kasprintf(&wacom->hdev->dev,
  							  GFP_KERNEL,
  							  "%d", serial);
  	if (!remote->remotes[index].group.name)
  		return -ENOMEM;
  
  	error = __wacom_devm_sysfs_create_group(wacom, remote->remote_dir,
  						&remote->remotes[index].group);
  	if (error) {
  		remote->remotes[index].group.name = NULL;
  		hid_err(wacom->hdev,
  			"cannot create sysfs group err: %d\n", error);
  		return error;
  	}
  
  	return 0;
  }
  
  static int wacom_cmd_unpair_remote(struct wacom *wacom, unsigned char selector)
  {
  	const size_t buf_size = 2;
  	unsigned char *buf;
  	int retval;
  
  	buf = kzalloc(buf_size, GFP_KERNEL);
  	if (!buf)
  		return -ENOMEM;
  
  	buf[0] = WAC_CMD_DELETE_PAIRING;
  	buf[1] = selector;
  
  	retval = wacom_set_report(wacom->hdev, HID_OUTPUT_REPORT, buf,
  				  buf_size, WAC_CMD_RETRIES);
  	kfree(buf);
  
  	return retval;
  }
  
  static ssize_t wacom_store_unpair_remote(struct kobject *kobj,
  					 struct kobj_attribute *attr,
  					 const char *buf, size_t count)
  {
  	unsigned char selector = 0;
  	struct device *dev = kobj_to_dev(kobj->parent);
  	struct hid_device *hdev = to_hid_device(dev);
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	int err;
  
  	if (!strncmp(buf, "*\n", 2)) {
  		selector = WAC_CMD_UNPAIR_ALL;
  	} else {
  		hid_info(wacom->hdev, "remote: unrecognized unpair code: %s\n",
  			 buf);
  		return -1;
  	}
  
  	mutex_lock(&wacom->lock);
  
  	err = wacom_cmd_unpair_remote(wacom, selector);
  	mutex_unlock(&wacom->lock);
  
  	return err < 0 ? err : count;
  }
  
  static struct kobj_attribute unpair_remote_attr = {
  	.attr = {.name = "unpair_remote", .mode = 0200},
  	.store = wacom_store_unpair_remote,
  };
  
  static const struct attribute *remote_unpair_attrs[] = {
  	&unpair_remote_attr.attr,
  	NULL
  };
  
  static void wacom_remotes_destroy(void *data)
  {
  	struct wacom *wacom = data;
  	struct wacom_remote *remote = wacom->remote;
  
  	if (!remote)
  		return;
  
  	kobject_put(remote->remote_dir);
  	kfifo_free(&remote->remote_fifo);
  	wacom->remote = NULL;
  }
  
  static int wacom_initialize_remotes(struct wacom *wacom)
  {
  	int error = 0;
  	struct wacom_remote *remote;
  	int i;
  
  	if (wacom->wacom_wac.features.type != REMOTE)
  		return 0;
  
  	remote = devm_kzalloc(&wacom->hdev->dev, sizeof(*wacom->remote),
  			      GFP_KERNEL);
  	if (!remote)
  		return -ENOMEM;
  
  	wacom->remote = remote;
  
  	spin_lock_init(&remote->remote_lock);
  
  	error = kfifo_alloc(&remote->remote_fifo,
  			5 * sizeof(struct wacom_remote_data),
  			GFP_KERNEL);
  	if (error) {
  		hid_err(wacom->hdev, "failed allocating remote_fifo\n");
  		return -ENOMEM;
  	}
  
  	remote->remotes[0].group = remote0_serial_group;
  	remote->remotes[1].group = remote1_serial_group;
  	remote->remotes[2].group = remote2_serial_group;
  	remote->remotes[3].group = remote3_serial_group;
  	remote->remotes[4].group = remote4_serial_group;
  
  	remote->remote_dir = kobject_create_and_add("wacom_remote",
  						    &wacom->hdev->dev.kobj);
  	if (!remote->remote_dir)
  		return -ENOMEM;
  
  	error = sysfs_create_files(remote->remote_dir, remote_unpair_attrs);
  
  	if (error) {
  		hid_err(wacom->hdev,
  			"cannot create sysfs group err: %d\n", error);
  		return error;
  	}
  
  	for (i = 0; i < WACOM_MAX_REMOTES; i++) {
  		wacom->led.groups[i].select = WACOM_STATUS_UNKNOWN;
  		remote->remotes[i].serial = 0;
  	}
  
  	error = devm_add_action_or_reset(&wacom->hdev->dev,
  					 wacom_remotes_destroy, wacom);
  	if (error)
  		return error;
  
  	return 0;
  }
  
  static struct input_dev *wacom_allocate_input(struct wacom *wacom)
  {
  	struct input_dev *input_dev;
  	struct hid_device *hdev = wacom->hdev;
  	struct wacom_wac *wacom_wac = &(wacom->wacom_wac);
  
  	input_dev = devm_input_allocate_device(&hdev->dev);
  	if (!input_dev)
  		return NULL;
  
  	input_dev->name = wacom_wac->features.name;
  	input_dev->phys = hdev->phys;
  	input_dev->dev.parent = &hdev->dev;
  	input_dev->open = wacom_open;
  	input_dev->close = wacom_close;
  	input_dev->uniq = hdev->uniq;
  	input_dev->id.bustype = hdev->bus;
  	input_dev->id.vendor  = hdev->vendor;
  	input_dev->id.product = wacom_wac->pid ? wacom_wac->pid : hdev->product;
  	input_dev->id.version = hdev->version;
  	input_set_drvdata(input_dev, wacom);
  
  	return input_dev;
  }
  
  static int wacom_allocate_inputs(struct wacom *wacom)
  {
  	struct wacom_wac *wacom_wac = &(wacom->wacom_wac);
  
  	wacom_wac->pen_input = wacom_allocate_input(wacom);
  	wacom_wac->touch_input = wacom_allocate_input(wacom);
  	wacom_wac->pad_input = wacom_allocate_input(wacom);
  	if (!wacom_wac->pen_input ||
  	    !wacom_wac->touch_input ||
  	    !wacom_wac->pad_input)
  		return -ENOMEM;
  
  	wacom_wac->pen_input->name = wacom_wac->pen_name;
  	wacom_wac->touch_input->name = wacom_wac->touch_name;
  	wacom_wac->pad_input->name = wacom_wac->pad_name;
  
  	return 0;
  }
  
  static int wacom_register_inputs(struct wacom *wacom)
  {
  	struct input_dev *pen_input_dev, *touch_input_dev, *pad_input_dev;
  	struct wacom_wac *wacom_wac = &(wacom->wacom_wac);
  	int error = 0;
  
  	pen_input_dev = wacom_wac->pen_input;
  	touch_input_dev = wacom_wac->touch_input;
  	pad_input_dev = wacom_wac->pad_input;
  
  	if (!pen_input_dev || !touch_input_dev || !pad_input_dev)
  		return -EINVAL;
  
  	error = wacom_setup_pen_input_capabilities(pen_input_dev, wacom_wac);
  	if (error) {
  		/* no pen in use on this interface */
  		input_free_device(pen_input_dev);
  		wacom_wac->pen_input = NULL;
  		pen_input_dev = NULL;
  	} else {
  		error = input_register_device(pen_input_dev);
  		if (error)
  			goto fail;
  	}
  
  	error = wacom_setup_touch_input_capabilities(touch_input_dev, wacom_wac);
  	if (error) {
  		/* no touch in use on this interface */
  		input_free_device(touch_input_dev);
  		wacom_wac->touch_input = NULL;
  		touch_input_dev = NULL;
  	} else {
  		error = input_register_device(touch_input_dev);
  		if (error)
  			goto fail;
  	}
  
  	error = wacom_setup_pad_input_capabilities(pad_input_dev, wacom_wac);
  	if (error) {
  		/* no pad in use on this interface */
  		input_free_device(pad_input_dev);
  		wacom_wac->pad_input = NULL;
  		pad_input_dev = NULL;
  	} else {
  		error = input_register_device(pad_input_dev);
  		if (error)
  			goto fail;
  	}
  
  	return 0;
  
  fail:
  	wacom_wac->pad_input = NULL;
  	wacom_wac->touch_input = NULL;
  	wacom_wac->pen_input = NULL;
  	return error;
  }
  
  /*
   * Not all devices report physical dimensions from HID.
   * Compute the default from hardcoded logical dimension
   * and resolution before driver overwrites them.
   */
  static void wacom_set_default_phy(struct wacom_features *features)
  {
  	if (features->x_resolution) {
  		features->x_phy = (features->x_max * 100) /
  					features->x_resolution;
  		features->y_phy = (features->y_max * 100) /
  					features->y_resolution;
  	}
  }
  
  static void wacom_calculate_res(struct wacom_features *features)
  {
  	/* set unit to "100th of a mm" for devices not reported by HID */
  	if (!features->unit) {
  		features->unit = 0x11;
  		features->unitExpo = -3;
  	}
  
  	features->x_resolution = wacom_calc_hid_res(features->x_max,
  						    features->x_phy,
  						    features->unit,
  						    features->unitExpo);
  	features->y_resolution = wacom_calc_hid_res(features->y_max,
  						    features->y_phy,
  						    features->unit,
  						    features->unitExpo);
  }
  
  void wacom_battery_work(struct work_struct *work)
  {
  	struct wacom *wacom = container_of(work, struct wacom, battery_work);
  
  	if ((wacom->wacom_wac.features.quirks & WACOM_QUIRK_BATTERY) &&
  	     !wacom->battery.battery) {
  		wacom_initialize_battery(wacom);
  	}
  	else if (!(wacom->wacom_wac.features.quirks & WACOM_QUIRK_BATTERY) &&
  		 wacom->battery.battery) {
  		wacom_destroy_battery(wacom);
  	}
  }
  
  static size_t wacom_compute_pktlen(struct hid_device *hdev)
  {
  	struct hid_report_enum *report_enum;
  	struct hid_report *report;
  	size_t size = 0;
  
  	report_enum = hdev->report_enum + HID_INPUT_REPORT;
  
  	list_for_each_entry(report, &report_enum->report_list, list) {
  		size_t report_size = hid_report_len(report);
  		if (report_size > size)
  			size = report_size;
  	}
  
  	return size;
  }
  
  static void wacom_update_name(struct wacom *wacom, const char *suffix)
  {
  	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
  	struct wacom_features *features = &wacom_wac->features;
  	char name[WACOM_NAME_MAX - 20]; /* Leave some room for suffixes */
  
  	/* Generic devices name unspecified */
  	if ((features->type == HID_GENERIC) && !strcmp("Wacom HID", features->name)) {
  		char *product_name = wacom->hdev->name;
  
  		if (hid_is_using_ll_driver(wacom->hdev, &usb_hid_driver)) {
  			struct usb_interface *intf = to_usb_interface(wacom->hdev->dev.parent);
  			struct usb_device *dev = interface_to_usbdev(intf);
  			product_name = dev->product;
  		}
  
  		if (wacom->hdev->bus == BUS_I2C) {
  			snprintf(name, sizeof(name), "%s %X",
  				 features->name, wacom->hdev->product);
  		} else if (strstr(product_name, "Wacom") ||
  			   strstr(product_name, "wacom") ||
  			   strstr(product_name, "WACOM")) {
  			strlcpy(name, product_name, sizeof(name));
  		} else {
  			snprintf(name, sizeof(name), "Wacom %s", product_name);
  		}
  
  		/* strip out excess whitespaces */
  		while (1) {
  			char *gap = strstr(name, "  ");
  			if (gap == NULL)
  				break;
  			/* shift everything including the terminator */
  			memmove(gap, gap+1, strlen(gap));
  		}
  
  		/* get rid of trailing whitespace */
  		if (name[strlen(name)-1] == ' ')
  			name[strlen(name)-1] = '\0';
  	} else {
  		strlcpy(name, features->name, sizeof(name));
  	}
  
  	snprintf(wacom_wac->name, sizeof(wacom_wac->name), "%s%s",
  		 name, suffix);
  
  	/* Append the device type to the name */
  	snprintf(wacom_wac->pen_name, sizeof(wacom_wac->pen_name),
  		"%s%s Pen", name, suffix);
  	snprintf(wacom_wac->touch_name, sizeof(wacom_wac->touch_name),
  		"%s%s Finger", name, suffix);
  	snprintf(wacom_wac->pad_name, sizeof(wacom_wac->pad_name),
  		"%s%s Pad", name, suffix);
  }
  
  static void wacom_release_resources(struct wacom *wacom)
  {
  	struct hid_device *hdev = wacom->hdev;
  
  	if (!wacom->resources)
  		return;
  
  	devres_release_group(&hdev->dev, wacom);
  
  	wacom->resources = false;
  
  	wacom->wacom_wac.pen_input = NULL;
  	wacom->wacom_wac.touch_input = NULL;
  	wacom->wacom_wac.pad_input = NULL;
  }
  
  static void wacom_set_shared_values(struct wacom_wac *wacom_wac)
  {
  	if (wacom_wac->features.device_type & WACOM_DEVICETYPE_TOUCH) {
  		wacom_wac->shared->type = wacom_wac->features.type;
  		wacom_wac->shared->touch_input = wacom_wac->touch_input;
  	}
  
  	if (wacom_wac->has_mute_touch_switch) {
  		wacom_wac->shared->has_mute_touch_switch = true;
  		wacom_wac->shared->is_touch_on = true;
  	}
  
  	if (wacom_wac->shared->has_mute_touch_switch &&
  	    wacom_wac->shared->touch_input) {
  		set_bit(EV_SW, wacom_wac->shared->touch_input->evbit);
  		input_set_capability(wacom_wac->shared->touch_input, EV_SW,
  				     SW_MUTE_DEVICE);
  	}
  }
  
  static int wacom_parse_and_register(struct wacom *wacom, bool wireless)
  {
  	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
  	struct wacom_features *features = &wacom_wac->features;
  	struct hid_device *hdev = wacom->hdev;
  	int error;
  	unsigned int connect_mask = HID_CONNECT_HIDRAW;
  
  	features->pktlen = wacom_compute_pktlen(hdev);
  	if (features->pktlen > WACOM_PKGLEN_MAX)
  		return -EINVAL;
  
  	if (!devres_open_group(&hdev->dev, wacom, GFP_KERNEL))
  		return -ENOMEM;
  
  	wacom->resources = true;
  
  	error = wacom_allocate_inputs(wacom);
  	if (error)
  		goto fail;
  
  	/*
  	 * Bamboo Pad has a generic hid handling for the Pen, and we switch it
  	 * into debug mode for the touch part.
  	 * We ignore the other interfaces.
  	 */
  	if (features->type == BAMBOO_PAD) {
  		if (features->pktlen == WACOM_PKGLEN_PENABLED) {
  			features->type = HID_GENERIC;
  		} else if ((features->pktlen != WACOM_PKGLEN_BPAD_TOUCH) &&
  			   (features->pktlen != WACOM_PKGLEN_BPAD_TOUCH_USB)) {
  			error = -ENODEV;
  			goto fail;
  		}
  	}
  
  	/* set the default size in case we do not get them from hid */
  	wacom_set_default_phy(features);
  
  	/* Retrieve the physical and logical size for touch devices */
  	wacom_retrieve_hid_descriptor(hdev, features);
  	wacom_setup_device_quirks(wacom);
  
  	if (features->device_type == WACOM_DEVICETYPE_NONE &&
  	    features->type != WIRELESS) {
  		error = features->type == HID_GENERIC ? -ENODEV : 0;
  
  		dev_warn(&hdev->dev, "Unknown device_type for '%s'. %s.",
  			 hdev->name,
  			 error ? "Ignoring" : "Assuming pen");
  
  		if (error)
  			goto fail;
  
  		features->device_type |= WACOM_DEVICETYPE_PEN;
  	}
  
  	wacom_calculate_res(features);
  
  	wacom_update_name(wacom, wireless ? " (WL)" : "");
  
  	/* pen only Bamboo neither support touch nor pad */
  	if ((features->type == BAMBOO_PEN) &&
  	    ((features->device_type & WACOM_DEVICETYPE_TOUCH) ||
  	    (features->device_type & WACOM_DEVICETYPE_PAD))) {
  		error = -ENODEV;
  		goto fail;
  	}
  
  	error = wacom_add_shared_data(hdev);
  	if (error)
  		goto fail;
  
  	if (!(features->device_type & WACOM_DEVICETYPE_WL_MONITOR) &&
  	     (features->quirks & WACOM_QUIRK_BATTERY)) {
  		error = wacom_initialize_battery(wacom);
  		if (error)
  			goto fail;
  	}
  
  	error = wacom_register_inputs(wacom);
  	if (error)
  		goto fail;
  
  	if (wacom->wacom_wac.features.device_type & WACOM_DEVICETYPE_PAD) {
  		error = wacom_initialize_leds(wacom);
  		if (error)
  			goto fail;
  
  		error = wacom_initialize_remotes(wacom);
  		if (error)
  			goto fail;
  	}
  
  	if (features->type == HID_GENERIC)
  		connect_mask |= HID_CONNECT_DRIVER;
  
  	/* Regular HID work starts now */
  	error = hid_hw_start(hdev, connect_mask);
  	if (error) {
  		hid_err(hdev, "hw start failed\n");
  		goto fail;
  	}
  
  	if (!wireless) {
  		/* Note that if query fails it is not a hard failure */
  		wacom_query_tablet_data(wacom);
  	}
  
  	/* touch only Bamboo doesn't support pen */
  	if ((features->type == BAMBOO_TOUCH) &&
  	    (features->device_type & WACOM_DEVICETYPE_PEN)) {
  		cancel_delayed_work_sync(&wacom->init_work);
  		_wacom_query_tablet_data(wacom);
  		error = -ENODEV;
  		goto fail_quirks;
  	}
  
  	if (features->device_type & WACOM_DEVICETYPE_WL_MONITOR)
  		error = hid_hw_open(hdev);
  
  	wacom_set_shared_values(wacom_wac);
  	devres_close_group(&hdev->dev, wacom);
  
  	return 0;
  
  fail_quirks:
  	hid_hw_stop(hdev);
  fail:
  	wacom_release_resources(wacom);
  	return error;
  }
  
  static void wacom_wireless_work(struct work_struct *work)
  {
  	struct wacom *wacom = container_of(work, struct wacom, wireless_work);
  	struct usb_device *usbdev = wacom->usbdev;
  	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
  	struct hid_device *hdev1, *hdev2;
  	struct wacom *wacom1, *wacom2;
  	struct wacom_wac *wacom_wac1, *wacom_wac2;
  	int error;
  
  	/*
  	 * Regardless if this is a disconnect or a new tablet,
  	 * remove any existing input and battery devices.
  	 */
  
  	wacom_destroy_battery(wacom);
  
  	/* Stylus interface */
  	hdev1 = usb_get_intfdata(usbdev->config->interface[1]);
  	wacom1 = hid_get_drvdata(hdev1);
  	wacom_wac1 = &(wacom1->wacom_wac);
  	wacom_release_resources(wacom1);
  
  	/* Touch interface */
  	hdev2 = usb_get_intfdata(usbdev->config->interface[2]);
  	wacom2 = hid_get_drvdata(hdev2);
  	wacom_wac2 = &(wacom2->wacom_wac);
  	wacom_release_resources(wacom2);
  
  	if (wacom_wac->pid == 0) {
  		hid_info(wacom->hdev, "wireless tablet disconnected\n");
  	} else {
  		const struct hid_device_id *id = wacom_ids;
  
  		hid_info(wacom->hdev, "wireless tablet connected with PID %x\n",
  			 wacom_wac->pid);
  
  		while (id->bus) {
  			if (id->vendor == USB_VENDOR_ID_WACOM &&
  			    id->product == wacom_wac->pid)
  				break;
  			id++;
  		}
  
  		if (!id->bus) {
  			hid_info(wacom->hdev, "ignoring unknown PID.\n");
  			return;
  		}
  
  		/* Stylus interface */
  		wacom_wac1->features =
  			*((struct wacom_features *)id->driver_data);
  
  		wacom_wac1->pid = wacom_wac->pid;
  		hid_hw_stop(hdev1);
  		error = wacom_parse_and_register(wacom1, true);
  		if (error)
  			goto fail;
  
  		/* Touch interface */
  		if (wacom_wac1->features.touch_max ||
  		    (wacom_wac1->features.type >= INTUOSHT &&
  		    wacom_wac1->features.type <= BAMBOO_PT)) {
  			wacom_wac2->features =
  				*((struct wacom_features *)id->driver_data);
  			wacom_wac2->pid = wacom_wac->pid;
  			hid_hw_stop(hdev2);
  			error = wacom_parse_and_register(wacom2, true);
  			if (error)
  				goto fail;
  		}
  
  		strlcpy(wacom_wac->name, wacom_wac1->name,
  			sizeof(wacom_wac->name));
  		error = wacom_initialize_battery(wacom);
  		if (error)
  			goto fail;
  	}
  
  	return;
  
  fail:
  	wacom_release_resources(wacom1);
  	wacom_release_resources(wacom2);
  	return;
  }
  
  static void wacom_remote_destroy_one(struct wacom *wacom, unsigned int index)
  {
  	struct wacom_remote *remote = wacom->remote;
  	u32 serial = remote->remotes[index].serial;
  	int i;
  	unsigned long flags;
  
  	for (i = 0; i < WACOM_MAX_REMOTES; i++) {
  		if (remote->remotes[i].serial == serial) {
  
  			spin_lock_irqsave(&remote->remote_lock, flags);
  			remote->remotes[i].registered = false;
  			spin_unlock_irqrestore(&remote->remote_lock, flags);
  
  			if (remote->remotes[i].battery.battery)
  				devres_release_group(&wacom->hdev->dev,
  						     &remote->remotes[i].battery.bat_desc);
  
  			if (remote->remotes[i].group.name)
  				devres_release_group(&wacom->hdev->dev,
  						     &remote->remotes[i]);
  
  			remote->remotes[i].serial = 0;
  			remote->remotes[i].group.name = NULL;
  			remote->remotes[i].battery.battery = NULL;
  			wacom->led.groups[i].select = WACOM_STATUS_UNKNOWN;
  		}
  	}
  }
  
  static int wacom_remote_create_one(struct wacom *wacom, u32 serial,
  				   unsigned int index)
  {
  	struct wacom_remote *remote = wacom->remote;
  	struct device *dev = &wacom->hdev->dev;
  	int error, k;
  
  	/* A remote can pair more than once with an EKR,
  	 * check to make sure this serial isn't already paired.
  	 */
  	for (k = 0; k < WACOM_MAX_REMOTES; k++) {
  		if (remote->remotes[k].serial == serial)
  			break;
  	}
  
  	if (k < WACOM_MAX_REMOTES) {
  		remote->remotes[index].serial = serial;
  		return 0;
  	}
  
  	if (!devres_open_group(dev, &remote->remotes[index], GFP_KERNEL))
  		return -ENOMEM;
  
  	error = wacom_remote_create_attr_group(wacom, serial, index);
  	if (error)
  		goto fail;
  
  	remote->remotes[index].input = wacom_allocate_input(wacom);
  	if (!remote->remotes[index].input) {
  		error = -ENOMEM;
  		goto fail;
  	}
  	remote->remotes[index].input->uniq = remote->remotes[index].group.name;
  	remote->remotes[index].input->name = wacom->wacom_wac.pad_name;
  
  	if (!remote->remotes[index].input->name) {
  		error = -EINVAL;
  		goto fail;
  	}
  
  	error = wacom_setup_pad_input_capabilities(remote->remotes[index].input,
  						   &wacom->wacom_wac);
  	if (error)
  		goto fail;
  
  	remote->remotes[index].serial = serial;
  
  	error = input_register_device(remote->remotes[index].input);
  	if (error)
  		goto fail;
  
  	error = wacom_led_groups_alloc_and_register_one(
  					&remote->remotes[index].input->dev,
  					wacom, index, 3, true);
  	if (error)
  		goto fail;
  
  	remote->remotes[index].registered = true;
  
  	devres_close_group(dev, &remote->remotes[index]);
  	return 0;
  
  fail:
  	devres_release_group(dev, &remote->remotes[index]);
  	remote->remotes[index].serial = 0;
  	return error;
  }
  
  static int wacom_remote_attach_battery(struct wacom *wacom, int index)
  {
  	struct wacom_remote *remote = wacom->remote;
  	int error;
  
  	if (!remote->remotes[index].registered)
  		return 0;
  
  	if (remote->remotes[index].battery.battery)
  		return 0;
  
  	if (wacom->led.groups[index].select == WACOM_STATUS_UNKNOWN)
  		return 0;
  
  	error = __wacom_initialize_battery(wacom,
  					&wacom->remote->remotes[index].battery);
  	if (error)
  		return error;
  
  	return 0;
  }
  
  static void wacom_remote_work(struct work_struct *work)
  {
  	struct wacom *wacom = container_of(work, struct wacom, remote_work);
  	struct wacom_remote *remote = wacom->remote;
  	struct wacom_remote_data data;
  	unsigned long flags;
  	unsigned int count;
  	u32 serial;
  	int i;
  
  	spin_lock_irqsave(&remote->remote_lock, flags);
  
  	count = kfifo_out(&remote->remote_fifo, &data, sizeof(data));
  
  	if (count != sizeof(data)) {
  		hid_err(wacom->hdev,
  			"workitem triggered without status available\n");
  		spin_unlock_irqrestore(&remote->remote_lock, flags);
  		return;
  	}
  
  	if (!kfifo_is_empty(&remote->remote_fifo))
  		wacom_schedule_work(&wacom->wacom_wac, WACOM_WORKER_REMOTE);
  
  	spin_unlock_irqrestore(&remote->remote_lock, flags);
  
  	for (i = 0; i < WACOM_MAX_REMOTES; i++) {
  		serial = data.remote[i].serial;
  		if (data.remote[i].connected) {
  
  			if (remote->remotes[i].serial == serial) {
  				wacom_remote_attach_battery(wacom, i);
  				continue;
  			}
  
  			if (remote->remotes[i].serial)
  				wacom_remote_destroy_one(wacom, i);
  
  			wacom_remote_create_one(wacom, serial, i);
  
  		} else if (remote->remotes[i].serial) {
  			wacom_remote_destroy_one(wacom, i);
  		}
  	}
  }
  
  static void wacom_mode_change_work(struct work_struct *work)
  {
  	struct wacom *wacom = container_of(work, struct wacom, mode_change_work);
  	struct wacom_shared *shared = wacom->wacom_wac.shared;
  	struct wacom *wacom1 = NULL;
  	struct wacom *wacom2 = NULL;
  	bool is_direct = wacom->wacom_wac.is_direct_mode;
  	int error = 0;
  
  	if (shared->pen) {
  		wacom1 = hid_get_drvdata(shared->pen);
  		wacom_release_resources(wacom1);
  		hid_hw_stop(wacom1->hdev);
  		wacom1->wacom_wac.has_mode_change = true;
  		wacom1->wacom_wac.is_direct_mode = is_direct;
  	}
  
  	if (shared->touch) {
  		wacom2 = hid_get_drvdata(shared->touch);
  		wacom_release_resources(wacom2);
  		hid_hw_stop(wacom2->hdev);
  		wacom2->wacom_wac.has_mode_change = true;
  		wacom2->wacom_wac.is_direct_mode = is_direct;
  	}
  
  	if (wacom1) {
  		error = wacom_parse_and_register(wacom1, false);
  		if (error)
  			return;
  	}
  
  	if (wacom2) {
  		error = wacom_parse_and_register(wacom2, false);
  		if (error)
  			return;
  	}
  
  	return;
  }
  
  static int wacom_probe(struct hid_device *hdev,
  		const struct hid_device_id *id)
  {
  	struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
  	struct usb_device *dev = interface_to_usbdev(intf);
  	struct wacom *wacom;
  	struct wacom_wac *wacom_wac;
  	struct wacom_features *features;
  	int error;
  
  	if (!id->driver_data)
  		return -EINVAL;
  
  	hdev->quirks |= HID_QUIRK_NO_INIT_REPORTS;
  
  	/* hid-core sets this quirk for the boot interface */
  	hdev->quirks &= ~HID_QUIRK_NOGET;
  
  	wacom = devm_kzalloc(&hdev->dev, sizeof(struct wacom), GFP_KERNEL);
  	if (!wacom)
  		return -ENOMEM;
  
  	hid_set_drvdata(hdev, wacom);
  	wacom->hdev = hdev;
  
  	wacom_wac = &wacom->wacom_wac;
  	wacom_wac->features = *((struct wacom_features *)id->driver_data);
  	features = &wacom_wac->features;
  
  	if (features->check_for_hid_type && features->hid_type != hdev->type)
  		return -ENODEV;
  
  	error = kfifo_alloc(&wacom_wac->pen_fifo, WACOM_PKGLEN_MAX, GFP_KERNEL);
  	if (error)
  		return error;
  
  	wacom_wac->hid_data.inputmode = -1;
  	wacom_wac->mode_report = -1;
  
  	wacom->usbdev = dev;
  	wacom->intf = intf;
  	mutex_init(&wacom->lock);
  	INIT_DELAYED_WORK(&wacom->init_work, wacom_init_work);
  	INIT_WORK(&wacom->wireless_work, wacom_wireless_work);
  	INIT_WORK(&wacom->battery_work, wacom_battery_work);
  	INIT_WORK(&wacom->remote_work, wacom_remote_work);
  	INIT_WORK(&wacom->mode_change_work, wacom_mode_change_work);
  
  	/* ask for the report descriptor to be loaded by HID */
  	error = hid_parse(hdev);
  	if (error) {
  		hid_err(hdev, "parse failed\n");
  		return error;
  	}
  
  	error = wacom_parse_and_register(wacom, false);
  	if (error)
  		return error;
  
  	if (hdev->bus == BUS_BLUETOOTH) {
  		error = device_create_file(&hdev->dev, &dev_attr_speed);
  		if (error)
  			hid_warn(hdev,
  				 "can't create sysfs speed attribute err: %d\n",
  				 error);
  	}
  
  	return 0;
  }
  
  static void wacom_remove(struct hid_device *hdev)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
  	struct wacom_features *features = &wacom_wac->features;
  
  	if (features->device_type & WACOM_DEVICETYPE_WL_MONITOR)
  		hid_hw_close(hdev);
  
  	hid_hw_stop(hdev);
  
  	cancel_delayed_work_sync(&wacom->init_work);
  	cancel_work_sync(&wacom->wireless_work);
  	cancel_work_sync(&wacom->battery_work);
  	cancel_work_sync(&wacom->remote_work);
  	cancel_work_sync(&wacom->mode_change_work);
  	if (hdev->bus == BUS_BLUETOOTH)
  		device_remove_file(&hdev->dev, &dev_attr_speed);
  
  	/* make sure we don't trigger the LEDs */
  	wacom_led_groups_release(wacom);
  
  	if (wacom->wacom_wac.features.type != REMOTE)
  		wacom_release_resources(wacom);
  
  	kfifo_free(&wacom_wac->pen_fifo);
  }
  
  #ifdef CONFIG_PM
  static int wacom_resume(struct hid_device *hdev)
  {
  	struct wacom *wacom = hid_get_drvdata(hdev);
  
  	mutex_lock(&wacom->lock);
  
  	/* switch to wacom mode first */
  	_wacom_query_tablet_data(wacom);
  	wacom_led_control(wacom);
  
  	mutex_unlock(&wacom->lock);
  
  	return 0;
  }
  
  static int wacom_reset_resume(struct hid_device *hdev)
  {
  	return wacom_resume(hdev);
  }
  #endif /* CONFIG_PM */
  
  static struct hid_driver wacom_driver = {
  	.name =		"wacom",
  	.id_table =	wacom_ids,
  	.probe =	wacom_probe,
  	.remove =	wacom_remove,
  	.report =	wacom_wac_report,
  #ifdef CONFIG_PM
  	.resume =	wacom_resume,
  	.reset_resume =	wacom_reset_resume,
  #endif
  	.raw_event =	wacom_raw_event,
  };
  module_hid_driver(wacom_driver);
  
  MODULE_VERSION(DRIVER_VERSION);
  MODULE_AUTHOR(DRIVER_AUTHOR);
  MODULE_DESCRIPTION(DRIVER_DESC);
  MODULE_LICENSE("GPL");
  