drivers/input/mouse/hil_ptr.c - LeafOS-Devices/android_kernel_realme_mt6785 - Gitiles

 /*
  * Generic linux-input device driver for axis-bearing devices
  *
  * Copyright (c) 2001 Brian S. Julin
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions, and the following disclaimer,
  *    without modification.
  * 2. The name of the author may not be used to endorse or promote products
  *    derived from this software without specific prior written permission.
  *
  * Alternatively, this software may be distributed under the terms of the
  * GNU General Public License ("GPL").
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  *
  * References:
  * HP-HIL Technical Reference Manual.  Hewlett Packard Product No. 45918A
  *
  */

 #include <linux/hil.h>
 #include <linux/input.h>
 #include <linux/serio.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/pci_ids.h>

 #define PREFIX "HIL PTR: "
 #define HIL_GENERIC_NAME "HIL pointer device"

 MODULE_AUTHOR("Brian S. Julin <bri@calyx.com>");
 MODULE_DESCRIPTION(HIL_GENERIC_NAME " driver");
 MODULE_LICENSE("Dual BSD/GPL");


 #define TABLET_SIMULATES_MOUSE	/* allow tablet to be used as mouse */
 #undef  TABLET_AUTOADJUST	/* auto-adjust valid tablet ranges */


 #define HIL_PTR_MAX_LENGTH 16

 struct hil_ptr {
 	struct input_dev *dev;
 	struct serio *serio;

 	/* Input buffer and index for packets from HIL bus. */
 	hil_packet data[HIL_PTR_MAX_LENGTH];
 	int idx4; /* four counts per packet */

 	/* Raw device info records from HIL bus, see hil.h for fields. */
 	char	idd[HIL_PTR_MAX_LENGTH];	/* DID byte and IDD record */
 	char	rsc[HIL_PTR_MAX_LENGTH];	/* RSC record */
 	char	exd[HIL_PTR_MAX_LENGTH];	/* EXD record */
 	char	rnm[HIL_PTR_MAX_LENGTH + 1];	/* RNM record + NULL term. */

 	/* Extra device details not contained in struct input_dev. */
 	unsigned int nbtn, naxes;
 	unsigned int btnmap[7];

 	/* Something to sleep around with. */
 	struct semaphore sem;
 };

 /* Process a complete packet after transfer from the HIL */
 static void hil_ptr_process_record(struct hil_ptr *ptr)
 {
 	struct input_dev *dev = ptr->dev;
 	hil_packet *data = ptr->data;
 	hil_packet p;
 	int idx, i, cnt, laxis;
 	int ax16, absdev;

 	idx = ptr->idx4/4;
 	p = data[idx - 1];

 	if ((p & ~HIL_CMDCT_POL) ==
 	    (HIL_ERR_INT | HIL_PKT_CMD | HIL_CMD_POL)) goto report;
 	if ((p & ~HIL_CMDCT_RPL) ==
 	    (HIL_ERR_INT | HIL_PKT_CMD | HIL_CMD_RPL)) goto report;

 	/* Not a poll response.  See if we are loading config records. */
 	switch (p & HIL_PKT_DATA_MASK) {
 	case HIL_CMD_IDD:
 		for (i = 0; i < idx; i++)
 			ptr->idd[i] = ptr->data[i] & HIL_PKT_DATA_MASK;
 		for (; i < HIL_PTR_MAX_LENGTH; i++)
 			ptr->idd[i] = 0;
 		break;
 	case HIL_CMD_RSC:
 		for (i = 0; i < idx; i++)
 			ptr->rsc[i] = ptr->data[i] & HIL_PKT_DATA_MASK;
 		for (; i < HIL_PTR_MAX_LENGTH; i++)
 			ptr->rsc[i] = 0;
 		break;
 	case HIL_CMD_EXD:
 		for (i = 0; i < idx; i++)
 			ptr->exd[i] = ptr->data[i] & HIL_PKT_DATA_MASK;
 		for (; i < HIL_PTR_MAX_LENGTH; i++)
 			ptr->exd[i] = 0;
 		break;
 	case HIL_CMD_RNM:
 		for (i = 0; i < idx; i++)
 			ptr->rnm[i] = ptr->data[i] & HIL_PKT_DATA_MASK;
 		for (; i < HIL_PTR_MAX_LENGTH + 1; i++)
 			ptr->rnm[i] = '\0';
 		break;
 	default:
 		/* These occur when device isn't present */
 		if (p == (HIL_ERR_INT | HIL_PKT_CMD)) break;
 		/* Anything else we'd like to know about. */
 		printk(KERN_WARNING PREFIX "Device sent unknown record %x\n", p);
 		break;
 	}
 	goto out;

  report:
 	if ((p & HIL_CMDCT_POL) != idx - 1) {
 		printk(KERN_WARNING PREFIX "Malformed poll packet %x (idx = %i)\n", p, idx);
 		goto out;
 	}

 	i = (ptr->data[0] & HIL_POL_AXIS_ALT) ? 3 : 0;
 	laxis = ptr->data[0] & HIL_POL_NUM_AXES_MASK;
 	laxis += i;

 	ax16 = ptr->idd[1] & HIL_IDD_HEADER_16BIT; /* 8 or 16bit resolution */
 	absdev = ptr->idd[1] & HIL_IDD_HEADER_ABS;

 	for (cnt = 1; i < laxis; i++) {
 		unsigned int lo,hi,val;
 		lo = ptr->data[cnt++] & HIL_PKT_DATA_MASK;
 		hi = ax16 ? (ptr->data[cnt++] & HIL_PKT_DATA_MASK) : 0;
 		if (absdev) {
 			val = lo + (hi<<8);
 #ifdef TABLET_AUTOADJUST
 			if (val < dev->absmin[ABS_X + i])
 				dev->absmin[ABS_X + i] = val;
 			if (val > dev->absmax[ABS_X + i])
 				dev->absmax[ABS_X + i] = val;
 #endif
 			if (i%3) val = dev->absmax[ABS_X + i] - val;
 			input_report_abs(dev, ABS_X + i, val);
 		} else {
 			val = (int) (((int8_t)lo) | ((int8_t)hi<<8));
 			if (i%3) val *= -1;
 			input_report_rel(dev, REL_X + i, val);
 		}
 	}

 	while (cnt < idx - 1) {
 		unsigned int btn;
 		int up;
 		btn = ptr->data[cnt++];
 		up = btn & 1;
 		btn &= 0xfe;
 		if (btn == 0x8e) {
 			continue; /* TODO: proximity == touch? */
 		}
 		else if ((btn > 0x8c) || (btn < 0x80)) continue;
 		btn = (btn - 0x80) >> 1;
 		btn = ptr->btnmap[btn];
 		input_report_key(dev, btn, !up);
 	}
 	input_sync(dev);
  out:
 	ptr->idx4 = 0;
 	up(&ptr->sem);
 }

 static void hil_ptr_process_err(struct hil_ptr *ptr) {
 	printk(KERN_WARNING PREFIX "errored HIL packet\n");
 	ptr->idx4 = 0;
 	up(&ptr->sem);
 	return;
 }

 static irqreturn_t hil_ptr_interrupt(struct serio *serio,
         unsigned char data, unsigned int flags)
 {
 	struct hil_ptr *ptr;
 	hil_packet packet;
 	int idx;

 	ptr = serio_get_drvdata(serio);
 	if (ptr == NULL) {
 		BUG();
 		return IRQ_HANDLED;
 	}

 	if (ptr->idx4 >= (HIL_PTR_MAX_LENGTH * sizeof(hil_packet))) {
 		hil_ptr_process_err(ptr);
 		return IRQ_HANDLED;
 	}
 	idx = ptr->idx4/4;
 	if (!(ptr->idx4 % 4)) ptr->data[idx] = 0;
 	packet = ptr->data[idx];
 	packet |= ((hil_packet)data) << ((3 - (ptr->idx4 % 4)) * 8);
 	ptr->data[idx] = packet;

 	/* Records of N 4-byte hil_packets must terminate with a command. */
 	if ((++(ptr->idx4)) % 4) return IRQ_HANDLED;
 	if ((packet & 0xffff0000) != HIL_ERR_INT) {
 		hil_ptr_process_err(ptr);
 		return IRQ_HANDLED;
 	}
 	if (packet & HIL_PKT_CMD)
 		hil_ptr_process_record(ptr);
 	return IRQ_HANDLED;
 }

 static void hil_ptr_disconnect(struct serio *serio)
 {
 	struct hil_ptr *ptr;

 	ptr = serio_get_drvdata(serio);
 	if (ptr == NULL) {
 		BUG();
 		return;
 	}

 	serio_close(serio);
 	input_unregister_device(ptr->dev);
 	kfree(ptr);
 }

 static int hil_ptr_connect(struct serio *serio, struct serio_driver *driver)
 {
 	struct hil_ptr	 *ptr;
 	char		 *txt;
 	unsigned int	 i, naxsets, btntype;
 	uint8_t		 did, *idd;

 	if (!(ptr = kzalloc(sizeof(struct hil_ptr), GFP_KERNEL)))
 		return -ENOMEM;

 	ptr->dev = input_allocate_device();
 	if (!ptr->dev)
 		goto bail0;

 	ptr->dev->private = ptr;

 	if (serio_open(serio, driver))
 		goto bail1;

 	serio_set_drvdata(serio, ptr);
 	ptr->serio = serio;

 	init_MUTEX_LOCKED(&(ptr->sem));

 	/* Get device info.  MLC driver supplies devid/status/etc. */
 	serio->write(serio, 0);
 	serio->write(serio, 0);
 	serio->write(serio, HIL_PKT_CMD >> 8);
 	serio->write(serio, HIL_CMD_IDD);
 	down(&(ptr->sem));

 	serio->write(serio, 0);
 	serio->write(serio, 0);
 	serio->write(serio, HIL_PKT_CMD >> 8);
 	serio->write(serio, HIL_CMD_RSC);
 	down(&(ptr->sem));

 	serio->write(serio, 0);
 	serio->write(serio, 0);
 	serio->write(serio, HIL_PKT_CMD >> 8);
 	serio->write(serio, HIL_CMD_RNM);
 	down(&(ptr->sem));

 	serio->write(serio, 0);
 	serio->write(serio, 0);
 	serio->write(serio, HIL_PKT_CMD >> 8);
 	serio->write(serio, HIL_CMD_EXD);
 	down(&(ptr->sem));

 	up(&(ptr->sem));

 	did = ptr->idd[0];
 	idd = ptr->idd + 1;
 	txt = "unknown";
 	if ((did & HIL_IDD_DID_TYPE_MASK) == HIL_IDD_DID_TYPE_REL) {
 		ptr->dev->evbit[0] = BIT(EV_REL);
 		txt = "relative";
 	}

 	if ((did & HIL_IDD_DID_TYPE_MASK) == HIL_IDD_DID_TYPE_ABS) {
 		ptr->dev->evbit[0] = BIT(EV_ABS);
 		txt = "absolute";
 	}
 	if (!ptr->dev->evbit[0]) {
 		goto bail2;
 	}

 	ptr->nbtn = HIL_IDD_NUM_BUTTONS(idd);
 	if (ptr->nbtn) ptr->dev->evbit[0] |= BIT(EV_KEY);

 	naxsets = HIL_IDD_NUM_AXSETS(*idd);
 	ptr->naxes = HIL_IDD_NUM_AXES_PER_SET(*idd);

 	printk(KERN_INFO PREFIX "HIL pointer device found (did: 0x%02x, axis: %s)\n",
 			did, txt);
 	printk(KERN_INFO PREFIX "HIL pointer has %i buttons and %i sets of %i axes\n",
 			ptr->nbtn, naxsets, ptr->naxes);

 	btntype = BTN_MISC;
 	if ((did & HIL_IDD_DID_ABS_TABLET_MASK) == HIL_IDD_DID_ABS_TABLET)
 #ifdef TABLET_SIMULATES_MOUSE
 		btntype = BTN_TOUCH;
 #else
 		btntype = BTN_DIGI;
 #endif
 	if ((did & HIL_IDD_DID_ABS_TSCREEN_MASK) == HIL_IDD_DID_ABS_TSCREEN)
 		btntype = BTN_TOUCH;

 	if ((did & HIL_IDD_DID_REL_MOUSE_MASK) == HIL_IDD_DID_REL_MOUSE)
 		btntype = BTN_MOUSE;

 	for (i = 0; i < ptr->nbtn; i++) {
 		set_bit(btntype | i, ptr->dev->keybit);
 		ptr->btnmap[i] = btntype | i;
 	}

 	if (btntype == BTN_MOUSE) {
 		/* Swap buttons 2 and 3 */
 		ptr->btnmap[1] = BTN_MIDDLE;
 		ptr->btnmap[2] = BTN_RIGHT;
 	}

 	if ((did & HIL_IDD_DID_TYPE_MASK) == HIL_IDD_DID_TYPE_REL) {
 		for (i = 0; i < ptr->naxes; i++) {
 			set_bit(REL_X + i, ptr->dev->relbit);
 		}
 		for (i = 3; (i < ptr->naxes + 3) && (naxsets > 1); i++) {
 			set_bit(REL_X + i, ptr->dev->relbit);
 		}
 	} else {
 		for (i = 0; i < ptr->naxes; i++) {
 			set_bit(ABS_X + i, ptr->dev->absbit);
 			ptr->dev->absmin[ABS_X + i] = 0;
 			ptr->dev->absmax[ABS_X + i] =
 				HIL_IDD_AXIS_MAX((ptr->idd + 1), i);
 		}
 		for (i = 3; (i < ptr->naxes + 3) && (naxsets > 1); i++) {
 			set_bit(ABS_X + i, ptr->dev->absbit);
 			ptr->dev->absmin[ABS_X + i] = 0;
 			ptr->dev->absmax[ABS_X + i] =
 				HIL_IDD_AXIS_MAX((ptr->idd + 1), (i - 3));
 		}
 #ifdef TABLET_AUTOADJUST
 		for (i = 0; i < ABS_MAX; i++) {
 			int diff = ptr->dev->absmax[ABS_X + i] / 10;
 			ptr->dev->absmin[ABS_X + i] += diff;
 			ptr->dev->absmax[ABS_X + i] -= diff;
 		}
 #endif
 	}

 	ptr->dev->name = strlen(ptr->rnm) ? ptr->rnm : HIL_GENERIC_NAME;

 	ptr->dev->id.bustype	= BUS_HIL;
 	ptr->dev->id.vendor	= PCI_VENDOR_ID_HP;
 	ptr->dev->id.product	= 0x0001; /* TODO: get from ptr->rsc */
 	ptr->dev->id.version	= 0x0100; /* TODO: get from ptr->rsc */
 	ptr->dev->dev		= &serio->dev;

 	input_register_device(ptr->dev);
 	printk(KERN_INFO "input: %s (%s), ID: %d\n",
 		ptr->dev->name,
 		(btntype == BTN_MOUSE) ? "HIL mouse":"HIL tablet or touchpad",
 		did);

 	return 0;
  bail2:
 	serio_close(serio);
  bail1:
 	input_free_device(ptr->dev);
  bail0:
 	kfree(ptr);
 	serio_set_drvdata(serio, NULL);
 	return -ENODEV;
 }

 static struct serio_device_id hil_ptr_ids[] = {
 	{
 		.type = SERIO_HIL_MLC,
 		.proto = SERIO_HIL,
 		.id = SERIO_ANY,
 		.extra = SERIO_ANY,
 	},
 	{ 0 }
 };

 static struct serio_driver hil_ptr_serio_driver = {
 	.driver		= {
 		.name	= "hil_ptr",
 	},
 	.description	= "HP HIL mouse/tablet driver",
 	.id_table	= hil_ptr_ids,
 	.connect	= hil_ptr_connect,
 	.disconnect	= hil_ptr_disconnect,
 	.interrupt	= hil_ptr_interrupt
 };

 static int __init hil_ptr_init(void)
 {
 	serio_register_driver(&hil_ptr_serio_driver);
         return 0;
 }

 static void __exit hil_ptr_exit(void)
 {
 	serio_unregister_driver(&hil_ptr_serio_driver);
 }

 module_init(hil_ptr_init);
 module_exit(hil_ptr_exit);
	/*
	* Generic linux-input device driver for axis-bearing devices
	*
	* Copyright (c) 2001 Brian S. Julin
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions, and the following disclaimer,
	* without modification.
	* 2. The name of the author may not be used to endorse or promote products
	* derived from this software without specific prior written permission.
	*
	* Alternatively, this software may be distributed under the terms of the
	* GNU General Public License ("GPL").
	*
	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
	* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	*
	* References:
	* HP-HIL Technical Reference Manual. Hewlett Packard Product No. 45918A
	*
	*/

	#include <linux/hil.h>
	#include <linux/input.h>
	#include <linux/serio.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/slab.h>
	#include <linux/pci_ids.h>

	#define PREFIX "HIL PTR: "
	#define HIL_GENERIC_NAME "HIL pointer device"

	MODULE_AUTHOR("Brian S. Julin <bri@calyx.com>");
	MODULE_DESCRIPTION(HIL_GENERIC_NAME " driver");
	MODULE_LICENSE("Dual BSD/GPL");


	#define TABLET_SIMULATES_MOUSE /* allow tablet to be used as mouse */
	#undef TABLET_AUTOADJUST /* auto-adjust valid tablet ranges */


	#define HIL_PTR_MAX_LENGTH 16

	struct hil_ptr {
	struct input_dev *dev;
	struct serio *serio;

	/* Input buffer and index for packets from HIL bus. */
	hil_packet data[HIL_PTR_MAX_LENGTH];
	int idx4; /* four counts per packet */

	/* Raw device info records from HIL bus, see hil.h for fields. */
	char idd[HIL_PTR_MAX_LENGTH]; /* DID byte and IDD record */
	char rsc[HIL_PTR_MAX_LENGTH]; /* RSC record */
	char exd[HIL_PTR_MAX_LENGTH]; /* EXD record */
	char rnm[HIL_PTR_MAX_LENGTH + 1]; /* RNM record + NULL term. */

	/* Extra device details not contained in struct input_dev. */
	unsigned int nbtn, naxes;
	unsigned int btnmap[7];

	/* Something to sleep around with. */
	struct semaphore sem;
	};

	/* Process a complete packet after transfer from the HIL */
	static void hil_ptr_process_record(struct hil_ptr *ptr)
	{
	struct input_dev *dev = ptr->dev;
	hil_packet *data = ptr->data;
	hil_packet p;
	int idx, i, cnt, laxis;
	int ax16, absdev;

	idx = ptr->idx4/4;
	p = data[idx - 1];

	if ((p & ~HIL_CMDCT_POL) ==
	(HIL_ERR_INT \| HIL_PKT_CMD \| HIL_CMD_POL)) goto report;
	if ((p & ~HIL_CMDCT_RPL) ==
	(HIL_ERR_INT \| HIL_PKT_CMD \| HIL_CMD_RPL)) goto report;

	/* Not a poll response. See if we are loading config records. */
	switch (p & HIL_PKT_DATA_MASK) {
	case HIL_CMD_IDD:
	for (i = 0; i < idx; i++)
	ptr->idd[i] = ptr->data[i] & HIL_PKT_DATA_MASK;
	for (; i < HIL_PTR_MAX_LENGTH; i++)
	ptr->idd[i] = 0;
	break;
	case HIL_CMD_RSC:
	for (i = 0; i < idx; i++)
	ptr->rsc[i] = ptr->data[i] & HIL_PKT_DATA_MASK;
	for (; i < HIL_PTR_MAX_LENGTH; i++)
	ptr->rsc[i] = 0;
	break;
	case HIL_CMD_EXD:
	for (i = 0; i < idx; i++)
	ptr->exd[i] = ptr->data[i] & HIL_PKT_DATA_MASK;
	for (; i < HIL_PTR_MAX_LENGTH; i++)
	ptr->exd[i] = 0;
	break;
	case HIL_CMD_RNM:
	for (i = 0; i < idx; i++)
	ptr->rnm[i] = ptr->data[i] & HIL_PKT_DATA_MASK;
	for (; i < HIL_PTR_MAX_LENGTH + 1; i++)
	ptr->rnm[i] = '\0';
	break;
	default:
	/* These occur when device isn't present */
	if (p == (HIL_ERR_INT \| HIL_PKT_CMD)) break;
	/* Anything else we'd like to know about. */
	printk(KERN_WARNING PREFIX "Device sent unknown record %x\n", p);
	break;
	}
	goto out;

	report:
	if ((p & HIL_CMDCT_POL) != idx - 1) {
	printk(KERN_WARNING PREFIX "Malformed poll packet %x (idx = %i)\n", p, idx);
	goto out;
	}

	i = (ptr->data[0] & HIL_POL_AXIS_ALT) ? 3 : 0;
	laxis = ptr->data[0] & HIL_POL_NUM_AXES_MASK;
	laxis += i;

	ax16 = ptr->idd[1] & HIL_IDD_HEADER_16BIT; /* 8 or 16bit resolution */
	absdev = ptr->idd[1] & HIL_IDD_HEADER_ABS;

	for (cnt = 1; i < laxis; i++) {
	unsigned int lo,hi,val;
	lo = ptr->data[cnt++] & HIL_PKT_DATA_MASK;
	hi = ax16 ? (ptr->data[cnt++] & HIL_PKT_DATA_MASK) : 0;
	if (absdev) {
	val = lo + (hi<<8);
	#ifdef TABLET_AUTOADJUST
	if (val < dev->absmin[ABS_X + i])
	dev->absmin[ABS_X + i] = val;
	if (val > dev->absmax[ABS_X + i])
	dev->absmax[ABS_X + i] = val;
	#endif
	if (i%3) val = dev->absmax[ABS_X + i] - val;
	input_report_abs(dev, ABS_X + i, val);
	} else {
	val = (int) (((int8_t)lo) \| ((int8_t)hi<<8));
	if (i%3) val *= -1;
	input_report_rel(dev, REL_X + i, val);
	}
	}

	while (cnt < idx - 1) {
	unsigned int btn;
	int up;
	btn = ptr->data[cnt++];
	up = btn & 1;
	btn &= 0xfe;
	if (btn == 0x8e) {
	continue; /* TODO: proximity == touch? */
	}
	else if ((btn > 0x8c) \|\| (btn < 0x80)) continue;
	btn = (btn - 0x80) >> 1;
	btn = ptr->btnmap[btn];
	input_report_key(dev, btn, !up);
	}
	input_sync(dev);
	out:
	ptr->idx4 = 0;
	up(&ptr->sem);
	}

	static void hil_ptr_process_err(struct hil_ptr *ptr) {
	printk(KERN_WARNING PREFIX "errored HIL packet\n");
	ptr->idx4 = 0;
	up(&ptr->sem);
	return;
	}

	static irqreturn_t hil_ptr_interrupt(struct serio *serio,
	unsigned char data, unsigned int flags)
	{
	struct hil_ptr *ptr;
	hil_packet packet;
	int idx;

	ptr = serio_get_drvdata(serio);
	if (ptr == NULL) {
	BUG();
	return IRQ_HANDLED;
	}

	if (ptr->idx4 >= (HIL_PTR_MAX_LENGTH * sizeof(hil_packet))) {
	hil_ptr_process_err(ptr);
	return IRQ_HANDLED;
	}
	idx = ptr->idx4/4;
	if (!(ptr->idx4 % 4)) ptr->data[idx] = 0;
	packet = ptr->data[idx];
	packet \|= ((hil_packet)data) << ((3 - (ptr->idx4 % 4)) * 8);
	ptr->data[idx] = packet;

	/* Records of N 4-byte hil_packets must terminate with a command. */
	if ((++(ptr->idx4)) % 4) return IRQ_HANDLED;
	if ((packet & 0xffff0000) != HIL_ERR_INT) {
	hil_ptr_process_err(ptr);
	return IRQ_HANDLED;
	}
	if (packet & HIL_PKT_CMD)
	hil_ptr_process_record(ptr);
	return IRQ_HANDLED;
	}

	static void hil_ptr_disconnect(struct serio *serio)
	{
	struct hil_ptr *ptr;

	ptr = serio_get_drvdata(serio);
	if (ptr == NULL) {
	BUG();
	return;
	}

	serio_close(serio);
	input_unregister_device(ptr->dev);
	kfree(ptr);
	}

	static int hil_ptr_connect(struct serio serio, struct serio_driver driver)
	{
	struct hil_ptr *ptr;
	char *txt;
	unsigned int i, naxsets, btntype;
	uint8_t did, *idd;

	if (!(ptr = kzalloc(sizeof(struct hil_ptr), GFP_KERNEL)))
	return -ENOMEM;

	ptr->dev = input_allocate_device();
	if (!ptr->dev)
	goto bail0;

	ptr->dev->private = ptr;

	if (serio_open(serio, driver))
	goto bail1;

	serio_set_drvdata(serio, ptr);
	ptr->serio = serio;

	init_MUTEX_LOCKED(&(ptr->sem));

	/* Get device info. MLC driver supplies devid/status/etc. */
	serio->write(serio, 0);
	serio->write(serio, 0);
	serio->write(serio, HIL_PKT_CMD >> 8);
	serio->write(serio, HIL_CMD_IDD);
	down(&(ptr->sem));

	serio->write(serio, 0);
	serio->write(serio, 0);
	serio->write(serio, HIL_PKT_CMD >> 8);
	serio->write(serio, HIL_CMD_RSC);
	down(&(ptr->sem));

	serio->write(serio, 0);
	serio->write(serio, 0);
	serio->write(serio, HIL_PKT_CMD >> 8);
	serio->write(serio, HIL_CMD_RNM);
	down(&(ptr->sem));

	serio->write(serio, 0);
	serio->write(serio, 0);
	serio->write(serio, HIL_PKT_CMD >> 8);
	serio->write(serio, HIL_CMD_EXD);
	down(&(ptr->sem));

	up(&(ptr->sem));

	did = ptr->idd[0];
	idd = ptr->idd + 1;
	txt = "unknown";
	if ((did & HIL_IDD_DID_TYPE_MASK) == HIL_IDD_DID_TYPE_REL) {
	ptr->dev->evbit[0] = BIT(EV_REL);
	txt = "relative";
	}

	if ((did & HIL_IDD_DID_TYPE_MASK) == HIL_IDD_DID_TYPE_ABS) {
	ptr->dev->evbit[0] = BIT(EV_ABS);
	txt = "absolute";
	}
	if (!ptr->dev->evbit[0]) {
	goto bail2;
	}

	ptr->nbtn = HIL_IDD_NUM_BUTTONS(idd);
	if (ptr->nbtn) ptr->dev->evbit[0] \|= BIT(EV_KEY);

	naxsets = HIL_IDD_NUM_AXSETS(*idd);
	ptr->naxes = HIL_IDD_NUM_AXES_PER_SET(*idd);

	printk(KERN_INFO PREFIX "HIL pointer device found (did: 0x%02x, axis: %s)\n",
	did, txt);
	printk(KERN_INFO PREFIX "HIL pointer has %i buttons and %i sets of %i axes\n",
	ptr->nbtn, naxsets, ptr->naxes);

	btntype = BTN_MISC;
	if ((did & HIL_IDD_DID_ABS_TABLET_MASK) == HIL_IDD_DID_ABS_TABLET)
	#ifdef TABLET_SIMULATES_MOUSE
	btntype = BTN_TOUCH;
	#else
	btntype = BTN_DIGI;
	#endif
	if ((did & HIL_IDD_DID_ABS_TSCREEN_MASK) == HIL_IDD_DID_ABS_TSCREEN)
	btntype = BTN_TOUCH;

	if ((did & HIL_IDD_DID_REL_MOUSE_MASK) == HIL_IDD_DID_REL_MOUSE)
	btntype = BTN_MOUSE;

	for (i = 0; i < ptr->nbtn; i++) {
	set_bit(btntype \| i, ptr->dev->keybit);
	ptr->btnmap[i] = btntype \| i;
	}

	if (btntype == BTN_MOUSE) {
	/* Swap buttons 2 and 3 */
	ptr->btnmap[1] = BTN_MIDDLE;
	ptr->btnmap[2] = BTN_RIGHT;
	}

	if ((did & HIL_IDD_DID_TYPE_MASK) == HIL_IDD_DID_TYPE_REL) {
	for (i = 0; i < ptr->naxes; i++) {
	set_bit(REL_X + i, ptr->dev->relbit);
	}
	for (i = 3; (i < ptr->naxes + 3) && (naxsets > 1); i++) {
	set_bit(REL_X + i, ptr->dev->relbit);
	}
	} else {
	for (i = 0; i < ptr->naxes; i++) {
	set_bit(ABS_X + i, ptr->dev->absbit);
	ptr->dev->absmin[ABS_X + i] = 0;
	ptr->dev->absmax[ABS_X + i] =
	HIL_IDD_AXIS_MAX((ptr->idd + 1), i);
	}
	for (i = 3; (i < ptr->naxes + 3) && (naxsets > 1); i++) {
	set_bit(ABS_X + i, ptr->dev->absbit);
	ptr->dev->absmin[ABS_X + i] = 0;
	ptr->dev->absmax[ABS_X + i] =
	HIL_IDD_AXIS_MAX((ptr->idd + 1), (i - 3));
	}
	#ifdef TABLET_AUTOADJUST
	for (i = 0; i < ABS_MAX; i++) {
	int diff = ptr->dev->absmax[ABS_X + i] / 10;
	ptr->dev->absmin[ABS_X + i] += diff;
	ptr->dev->absmax[ABS_X + i] -= diff;
	}
	#endif
	}

	ptr->dev->name = strlen(ptr->rnm) ? ptr->rnm : HIL_GENERIC_NAME;

	ptr->dev->id.bustype = BUS_HIL;
	ptr->dev->id.vendor = PCI_VENDOR_ID_HP;
	ptr->dev->id.product = 0x0001; /* TODO: get from ptr->rsc */
	ptr->dev->id.version = 0x0100; /* TODO: get from ptr->rsc */
	ptr->dev->dev = &serio->dev;

	input_register_device(ptr->dev);
	printk(KERN_INFO "input: %s (%s), ID: %d\n",
	ptr->dev->name,
	(btntype == BTN_MOUSE) ? "HIL mouse":"HIL tablet or touchpad",
	did);

	return 0;
	bail2:
	serio_close(serio);
	bail1:
	input_free_device(ptr->dev);
	bail0:
	kfree(ptr);
	serio_set_drvdata(serio, NULL);
	return -ENODEV;
	}

	static struct serio_device_id hil_ptr_ids[] = {
	{
	.type = SERIO_HIL_MLC,
	.proto = SERIO_HIL,
	.id = SERIO_ANY,
	.extra = SERIO_ANY,
	},
	{ 0 }
	};

	static struct serio_driver hil_ptr_serio_driver = {
	.driver = {
	.name = "hil_ptr",
	},
	.description = "HP HIL mouse/tablet driver",
	.id_table = hil_ptr_ids,
	.connect = hil_ptr_connect,
	.disconnect = hil_ptr_disconnect,
	.interrupt = hil_ptr_interrupt
	};

	static int __init hil_ptr_init(void)
	{
	serio_register_driver(&hil_ptr_serio_driver);
	return 0;
	}

	static void __exit hil_ptr_exit(void)
	{
	serio_unregister_driver(&hil_ptr_serio_driver);
	}

	module_init(hil_ptr_init);
	module_exit(hil_ptr_exit);