drivers/input/mouse/focaltech.c - kernel/msm-4.9 - Gitiles

 /*
  * Focaltech TouchPad PS/2 mouse driver
  *
  * Copyright (c) 2014 Red Hat Inc.
  * Copyright (c) 2014 Mathias Gottschlag <mgottschlag@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * Red Hat authors:
  *
  * Hans de Goede <hdegoede@redhat.com>
  */


 #include <linux/device.h>
 #include <linux/libps2.h>
 #include <linux/input/mt.h>
 #include <linux/serio.h>
 #include <linux/slab.h>
 #include "psmouse.h"
 #include "focaltech.h"

 static const char * const focaltech_pnp_ids[] = {
 	"FLT0101",
 	"FLT0102",
 	"FLT0103",
 	NULL
 };

 /*
  * Even if the kernel is built without support for Focaltech PS/2 touchpads (or
  * when the real driver fails to recognize the device), we still have to detect
  * them in order to avoid further detection attempts confusing the touchpad.
  * This way it at least works in PS/2 mouse compatibility mode.
  */
 int focaltech_detect(struct psmouse *psmouse, bool set_properties)
 {
 	if (!psmouse_matches_pnp_id(psmouse, focaltech_pnp_ids))
 		return -ENODEV;

 	if (set_properties) {
 		psmouse->vendor = "FocalTech";
 		psmouse->name = "FocalTech Touchpad";
 	}

 	return 0;
 }

 static void focaltech_reset(struct psmouse *psmouse)
 {
 	ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
 	psmouse_reset(psmouse);
 }

 #ifdef CONFIG_MOUSE_PS2_FOCALTECH

 /*
  * Packet types - the numbers are not consecutive, so we might be missing
  * something here.
  */
 #define FOC_TOUCH 0x3 /* bitmap of active fingers */
 #define FOC_ABS 0x6 /* absolute position of one finger */
 #define FOC_REL 0x9 /* relative position of 1-2 fingers */

 #define FOC_MAX_FINGERS 5

 #define FOC_MAX_X 2431
 #define FOC_MAX_Y 1663

 /*
  * Current state of a single finger on the touchpad.
  */
 struct focaltech_finger_state {
 	/* The touchpad has generated a touch event for the finger */
 	bool active;

 	/*
 	 * The touchpad has sent position data for the finger. The
 	 * flag is 0 when the finger is not active, and there is a
 	 * time between the first touch event for the finger and the
 	 * following absolute position packet for the finger where the
 	 * touchpad has declared the finger to be valid, but we do not
 	 * have any valid position yet.
 	 */
 	bool valid;

 	/*
 	 * Absolute position (from the bottom left corner) of the
 	 * finger.
 	 */
 	unsigned int x;
 	unsigned int y;
 };

 /*
  * Description of the current state of the touchpad hardware.
  */
 struct focaltech_hw_state {
 	/*
 	 * The touchpad tracks the positions of the fingers for us,
 	 * the array indices correspond to the finger indices returned
 	 * in the report packages.
 	 */
 	struct focaltech_finger_state fingers[FOC_MAX_FINGERS];

 	/* True if the clickpad has been pressed. */
 	bool pressed;
 };

 struct focaltech_data {
 	unsigned int x_max, y_max;
 	struct focaltech_hw_state state;
 };

 static void focaltech_report_state(struct psmouse *psmouse)
 {
 	struct focaltech_data *priv = psmouse->private;
 	struct focaltech_hw_state *state = &priv->state;
 	struct input_dev *dev = psmouse->dev;
 	int i;

 	for (i = 0; i < FOC_MAX_FINGERS; i++) {
 		struct focaltech_finger_state *finger = &state->fingers[i];
 		bool active = finger->active && finger->valid;

 		input_mt_slot(dev, i);
 		input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
 		if (active) {
 			input_report_abs(dev, ABS_MT_POSITION_X, finger->x);
 			input_report_abs(dev, ABS_MT_POSITION_Y,
 					 FOC_MAX_Y - finger->y);
 		}
 	}
 	input_mt_report_pointer_emulation(dev, true);

 	input_report_key(psmouse->dev, BTN_LEFT, state->pressed);
 	input_sync(psmouse->dev);
 }

 static void focaltech_process_touch_packet(struct psmouse *psmouse,
 					   unsigned char *packet)
 {
 	struct focaltech_data *priv = psmouse->private;
 	struct focaltech_hw_state *state = &priv->state;
 	unsigned char fingers = packet[1];
 	int i;

 	state->pressed = (packet[0] >> 4) & 1;

 	/* the second byte contains a bitmap of all fingers touching the pad */
 	for (i = 0; i < FOC_MAX_FINGERS; i++) {
 		state->fingers[i].active = fingers & 0x1;
 		if (!state->fingers[i].active) {
 			/*
 			 * Even when the finger becomes active again, we still
 			 * will have to wait for the first valid position.
 			 */
 			state->fingers[i].valid = false;
 		}
 		fingers >>= 1;
 	}
 }

 static void focaltech_process_abs_packet(struct psmouse *psmouse,
 					 unsigned char *packet)
 {
 	struct focaltech_data *priv = psmouse->private;
 	struct focaltech_hw_state *state = &priv->state;
 	unsigned int finger;

 	finger = (packet[1] >> 4) - 1;
 	if (finger >= FOC_MAX_FINGERS) {
 		psmouse_err(psmouse, "Invalid finger in abs packet: %d\n",
 			    finger);
 		return;
 	}

 	state->pressed = (packet[0] >> 4) & 1;

 	/*
 	 * packet[5] contains some kind of tool size in the most
 	 * significant nibble. 0xff is a special value (latching) that
 	 * signals a large contact area.
 	 */
 	if (packet[5] == 0xff) {
 		state->fingers[finger].valid = false;
 		return;
 	}

 	state->fingers[finger].x = ((packet[1] & 0xf) << 8) | packet[2];
 	state->fingers[finger].y = (packet[3] << 8) | packet[4];
 	state->fingers[finger].valid = true;
 }

 static void focaltech_process_rel_packet(struct psmouse *psmouse,
 					 unsigned char *packet)
 {
 	struct focaltech_data *priv = psmouse->private;
 	struct focaltech_hw_state *state = &priv->state;
 	int finger1, finger2;

 	state->pressed = packet[0] >> 7;
 	finger1 = ((packet[0] >> 4) & 0x7) - 1;
 	if (finger1 < FOC_MAX_FINGERS) {
 		state->fingers[finger1].x += (char)packet[1];
 		state->fingers[finger1].y += (char)packet[2];
 	} else {
 		psmouse_err(psmouse, "First finger in rel packet invalid: %d\n",
 			    finger1);
 	}

 	/*
 	 * If there is an odd number of fingers, the last relative
 	 * packet only contains one finger. In this case, the second
 	 * finger index in the packet is 0 (we subtract 1 in the lines
 	 * above to create array indices, so the finger will overflow
 	 * and be above FOC_MAX_FINGERS).
 	 */
 	finger2 = ((packet[3] >> 4) & 0x7) - 1;
 	if (finger2 < FOC_MAX_FINGERS) {
 		state->fingers[finger2].x += (char)packet[4];
 		state->fingers[finger2].y += (char)packet[5];
 	}
 }

 static void focaltech_process_packet(struct psmouse *psmouse)
 {
 	unsigned char *packet = psmouse->packet;

 	switch (packet[0] & 0xf) {
 	case FOC_TOUCH:
 		focaltech_process_touch_packet(psmouse, packet);
 		break;

 	case FOC_ABS:
 		focaltech_process_abs_packet(psmouse, packet);
 		break;

 	case FOC_REL:
 		focaltech_process_rel_packet(psmouse, packet);
 		break;

 	default:
 		psmouse_err(psmouse, "Unknown packet type: %02x\n", packet[0]);
 		break;
 	}

 	focaltech_report_state(psmouse);
 }

 static psmouse_ret_t focaltech_process_byte(struct psmouse *psmouse)
 {
 	if (psmouse->pktcnt >= 6) { /* Full packet received */
 		focaltech_process_packet(psmouse);
 		return PSMOUSE_FULL_PACKET;
 	}

 	/*
 	 * We might want to do some validation of the data here, but
 	 * we do not know the protocol well enough
 	 */
 	return PSMOUSE_GOOD_DATA;
 }

 static int focaltech_switch_protocol(struct psmouse *psmouse)
 {
 	struct ps2dev *ps2dev = &psmouse->ps2dev;
 	unsigned char param[3];

 	param[0] = 0;
 	if (ps2_command(ps2dev, param, 0x10f8))
 		return -EIO;

 	if (ps2_command(ps2dev, param, 0x10f8))
 		return -EIO;

 	if (ps2_command(ps2dev, param, 0x10f8))
 		return -EIO;

 	param[0] = 1;
 	if (ps2_command(ps2dev, param, 0x10f8))
 		return -EIO;

 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
 		return -EIO;

 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_ENABLE))
 		return -EIO;

 	return 0;
 }

 static void focaltech_disconnect(struct psmouse *psmouse)
 {
 	focaltech_reset(psmouse);
 	kfree(psmouse->private);
 	psmouse->private = NULL;
 }

 static int focaltech_reconnect(struct psmouse *psmouse)
 {
 	int error;

 	focaltech_reset(psmouse);

 	error = focaltech_switch_protocol(psmouse);
 	if (error) {
 		psmouse_err(psmouse, "Unable to initialize the device\n");
 		return error;
 	}

 	return 0;
 }

 static void focaltech_set_input_params(struct psmouse *psmouse)
 {
 	struct input_dev *dev = psmouse->dev;
 	struct focaltech_data *priv = psmouse->private;

 	/*
 	 * Undo part of setup done for us by psmouse core since touchpad
 	 * is not a relative device.
 	 */
 	__clear_bit(EV_REL, dev->evbit);
 	__clear_bit(REL_X, dev->relbit);
 	__clear_bit(REL_Y, dev->relbit);
 	__clear_bit(BTN_RIGHT, dev->keybit);
 	__clear_bit(BTN_MIDDLE, dev->keybit);

 	/*
 	 * Now set up our capabilities.
 	 */
 	__set_bit(EV_ABS, dev->evbit);
 	input_set_abs_params(dev, ABS_MT_POSITION_X, 0, priv->x_max, 0, 0);
 	input_set_abs_params(dev, ABS_MT_POSITION_Y, 0, priv->y_max, 0, 0);
 	input_mt_init_slots(dev, 5, INPUT_MT_POINTER);
 	__set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
 }

 static int focaltech_read_register(struct ps2dev *ps2dev, int reg,
 				   unsigned char *param)
 {
 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
 		return -EIO;

 	param[0] = 0;
 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
 		return -EIO;

 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
 		return -EIO;

 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
 		return -EIO;

 	param[0] = reg;
 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
 		return -EIO;

 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
 		return -EIO;

 	return 0;
 }

 static int focaltech_read_size(struct psmouse *psmouse)
 {
 	struct ps2dev *ps2dev = &psmouse->ps2dev;
 	struct focaltech_data *priv = psmouse->private;
 	char param[3];

 	if (focaltech_read_register(ps2dev, 2, param))
 		return -EIO;

 	/* not sure whether this is 100% correct */
 	priv->x_max = (unsigned char)param[1] * 128;
 	priv->y_max = (unsigned char)param[2] * 128;

 	return 0;
 }
 int focaltech_init(struct psmouse *psmouse)
 {
 	struct focaltech_data *priv;
 	int error;

 	psmouse->private = priv = kzalloc(sizeof(struct focaltech_data),
 					  GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	focaltech_reset(psmouse);

 	error = focaltech_read_size(psmouse);
 	if (error) {
 		psmouse_err(psmouse,
 			    "Unable to read the size of the touchpad\n");
 		goto fail;
 	}

 	error = focaltech_switch_protocol(psmouse);
 	if (error) {
 		psmouse_err(psmouse, "Unable to initialize the device\n");
 		goto fail;
 	}

 	focaltech_set_input_params(psmouse);

 	psmouse->protocol_handler = focaltech_process_byte;
 	psmouse->pktsize = 6;
 	psmouse->disconnect = focaltech_disconnect;
 	psmouse->reconnect = focaltech_reconnect;
 	psmouse->cleanup = focaltech_reset;
 	/* resync is not supported yet */
 	psmouse->resync_time = 0;

 	return 0;

 fail:
 	focaltech_reset(psmouse);
 	kfree(priv);
 	return error;
 }

 #else /* CONFIG_MOUSE_PS2_FOCALTECH */

 int focaltech_init(struct psmouse *psmouse)
 {
 	focaltech_reset(psmouse);

 	return 0;
 }

 #endif /* CONFIG_MOUSE_PS2_FOCALTECH */
	/*
	* Focaltech TouchPad PS/2 mouse driver
	*
	* Copyright (c) 2014 Red Hat Inc.
	* Copyright (c) 2014 Mathias Gottschlag <mgottschlag@gmail.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* Red Hat authors:
	*
	* Hans de Goede <hdegoede@redhat.com>
	*/


	#include <linux/device.h>
	#include <linux/libps2.h>
	#include <linux/input/mt.h>
	#include <linux/serio.h>
	#include <linux/slab.h>
	#include "psmouse.h"
	#include "focaltech.h"

	static const char * const focaltech_pnp_ids[] = {
	"FLT0101",
	"FLT0102",
	"FLT0103",
	NULL
	};

	/*
	* Even if the kernel is built without support for Focaltech PS/2 touchpads (or
	* when the real driver fails to recognize the device), we still have to detect
	* them in order to avoid further detection attempts confusing the touchpad.
	* This way it at least works in PS/2 mouse compatibility mode.
	*/
	int focaltech_detect(struct psmouse *psmouse, bool set_properties)
	{
	if (!psmouse_matches_pnp_id(psmouse, focaltech_pnp_ids))
	return -ENODEV;

	if (set_properties) {
	psmouse->vendor = "FocalTech";
	psmouse->name = "FocalTech Touchpad";
	}

	return 0;
	}

	static void focaltech_reset(struct psmouse *psmouse)
	{
	ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
	psmouse_reset(psmouse);
	}

	#ifdef CONFIG_MOUSE_PS2_FOCALTECH

	/*
	* Packet types - the numbers are not consecutive, so we might be missing
	* something here.
	*/
	#define FOC_TOUCH 0x3 /* bitmap of active fingers */
	#define FOC_ABS 0x6 /* absolute position of one finger */
	#define FOC_REL 0x9 /* relative position of 1-2 fingers */

	#define FOC_MAX_FINGERS 5

	#define FOC_MAX_X 2431
	#define FOC_MAX_Y 1663

	/*
	* Current state of a single finger on the touchpad.
	*/
	struct focaltech_finger_state {
	/* The touchpad has generated a touch event for the finger */
	bool active;

	/*
	* The touchpad has sent position data for the finger. The
	* flag is 0 when the finger is not active, and there is a
	* time between the first touch event for the finger and the
	* following absolute position packet for the finger where the
	* touchpad has declared the finger to be valid, but we do not
	* have any valid position yet.
	*/
	bool valid;

	/*
	* Absolute position (from the bottom left corner) of the
	* finger.
	*/
	unsigned int x;
	unsigned int y;
	};

	/*
	* Description of the current state of the touchpad hardware.
	*/
	struct focaltech_hw_state {
	/*
	* The touchpad tracks the positions of the fingers for us,
	* the array indices correspond to the finger indices returned
	* in the report packages.
	*/
	struct focaltech_finger_state fingers[FOC_MAX_FINGERS];

	/* True if the clickpad has been pressed. */
	bool pressed;
	};

	struct focaltech_data {
	unsigned int x_max, y_max;
	struct focaltech_hw_state state;
	};

	static void focaltech_report_state(struct psmouse *psmouse)
	{
	struct focaltech_data *priv = psmouse->private;
	struct focaltech_hw_state *state = &priv->state;
	struct input_dev *dev = psmouse->dev;
	int i;

	for (i = 0; i < FOC_MAX_FINGERS; i++) {
	struct focaltech_finger_state *finger = &state->fingers[i];
	bool active = finger->active && finger->valid;

	input_mt_slot(dev, i);
	input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
	if (active) {
	input_report_abs(dev, ABS_MT_POSITION_X, finger->x);
	input_report_abs(dev, ABS_MT_POSITION_Y,
	FOC_MAX_Y - finger->y);
	}
	}
	input_mt_report_pointer_emulation(dev, true);

	input_report_key(psmouse->dev, BTN_LEFT, state->pressed);
	input_sync(psmouse->dev);
	}

	static void focaltech_process_touch_packet(struct psmouse *psmouse,
	unsigned char *packet)
	{
	struct focaltech_data *priv = psmouse->private;
	struct focaltech_hw_state *state = &priv->state;
	unsigned char fingers = packet[1];
	int i;

	state->pressed = (packet[0] >> 4) & 1;

	/* the second byte contains a bitmap of all fingers touching the pad */
	for (i = 0; i < FOC_MAX_FINGERS; i++) {
	state->fingers[i].active = fingers & 0x1;
	if (!state->fingers[i].active) {
	/*
	* Even when the finger becomes active again, we still
	* will have to wait for the first valid position.
	*/
	state->fingers[i].valid = false;
	}
	fingers >>= 1;
	}
	}

	static void focaltech_process_abs_packet(struct psmouse *psmouse,
	unsigned char *packet)
	{
	struct focaltech_data *priv = psmouse->private;
	struct focaltech_hw_state *state = &priv->state;
	unsigned int finger;

	finger = (packet[1] >> 4) - 1;
	if (finger >= FOC_MAX_FINGERS) {
	psmouse_err(psmouse, "Invalid finger in abs packet: %d\n",
	finger);
	return;
	}

	state->pressed = (packet[0] >> 4) & 1;

	/*
	* packet[5] contains some kind of tool size in the most
	* significant nibble. 0xff is a special value (latching) that
	* signals a large contact area.
	*/
	if (packet[5] == 0xff) {
	state->fingers[finger].valid = false;
	return;
	}

	state->fingers[finger].x = ((packet[1] & 0xf) << 8) \| packet[2];
	state->fingers[finger].y = (packet[3] << 8) \| packet[4];
	state->fingers[finger].valid = true;
	}

	static void focaltech_process_rel_packet(struct psmouse *psmouse,
	unsigned char *packet)
	{
	struct focaltech_data *priv = psmouse->private;
	struct focaltech_hw_state *state = &priv->state;
	int finger1, finger2;

	state->pressed = packet[0] >> 7;
	finger1 = ((packet[0] >> 4) & 0x7) - 1;
	if (finger1 < FOC_MAX_FINGERS) {
	state->fingers[finger1].x += (char)packet[1];
	state->fingers[finger1].y += (char)packet[2];
	} else {
	psmouse_err(psmouse, "First finger in rel packet invalid: %d\n",
	finger1);
	}

	/*
	* If there is an odd number of fingers, the last relative
	* packet only contains one finger. In this case, the second
	* finger index in the packet is 0 (we subtract 1 in the lines
	* above to create array indices, so the finger will overflow
	* and be above FOC_MAX_FINGERS).
	*/
	finger2 = ((packet[3] >> 4) & 0x7) - 1;
	if (finger2 < FOC_MAX_FINGERS) {
	state->fingers[finger2].x += (char)packet[4];
	state->fingers[finger2].y += (char)packet[5];
	}
	}

	static void focaltech_process_packet(struct psmouse *psmouse)
	{
	unsigned char *packet = psmouse->packet;

	switch (packet[0] & 0xf) {
	case FOC_TOUCH:
	focaltech_process_touch_packet(psmouse, packet);
	break;

	case FOC_ABS:
	focaltech_process_abs_packet(psmouse, packet);
	break;

	case FOC_REL:
	focaltech_process_rel_packet(psmouse, packet);
	break;

	default:
	psmouse_err(psmouse, "Unknown packet type: %02x\n", packet[0]);
	break;
	}

	focaltech_report_state(psmouse);
	}

	static psmouse_ret_t focaltech_process_byte(struct psmouse *psmouse)
	{
	if (psmouse->pktcnt >= 6) { /* Full packet received */
	focaltech_process_packet(psmouse);
	return PSMOUSE_FULL_PACKET;
	}

	/*
	* We might want to do some validation of the data here, but
	* we do not know the protocol well enough
	*/
	return PSMOUSE_GOOD_DATA;
	}

	static int focaltech_switch_protocol(struct psmouse *psmouse)
	{
	struct ps2dev *ps2dev = &psmouse->ps2dev;
	unsigned char param[3];

	param[0] = 0;
	if (ps2_command(ps2dev, param, 0x10f8))
	return -EIO;

	if (ps2_command(ps2dev, param, 0x10f8))
	return -EIO;

	if (ps2_command(ps2dev, param, 0x10f8))
	return -EIO;

	param[0] = 1;
	if (ps2_command(ps2dev, param, 0x10f8))
	return -EIO;

	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
	return -EIO;

	if (ps2_command(ps2dev, param, PSMOUSE_CMD_ENABLE))
	return -EIO;

	return 0;
	}

	static void focaltech_disconnect(struct psmouse *psmouse)
	{
	focaltech_reset(psmouse);
	kfree(psmouse->private);
	psmouse->private = NULL;
	}

	static int focaltech_reconnect(struct psmouse *psmouse)
	{
	int error;

	focaltech_reset(psmouse);

	error = focaltech_switch_protocol(psmouse);
	if (error) {
	psmouse_err(psmouse, "Unable to initialize the device\n");
	return error;
	}

	return 0;
	}

	static void focaltech_set_input_params(struct psmouse *psmouse)
	{
	struct input_dev *dev = psmouse->dev;
	struct focaltech_data *priv = psmouse->private;

	/*
	* Undo part of setup done for us by psmouse core since touchpad
	* is not a relative device.
	*/
	__clear_bit(EV_REL, dev->evbit);
	__clear_bit(REL_X, dev->relbit);
	__clear_bit(REL_Y, dev->relbit);
	__clear_bit(BTN_RIGHT, dev->keybit);
	__clear_bit(BTN_MIDDLE, dev->keybit);

	/*
	* Now set up our capabilities.
	*/
	__set_bit(EV_ABS, dev->evbit);
	input_set_abs_params(dev, ABS_MT_POSITION_X, 0, priv->x_max, 0, 0);
	input_set_abs_params(dev, ABS_MT_POSITION_Y, 0, priv->y_max, 0, 0);
	input_mt_init_slots(dev, 5, INPUT_MT_POINTER);
	__set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
	}

	static int focaltech_read_register(struct ps2dev *ps2dev, int reg,
	unsigned char *param)
	{
	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
	return -EIO;

	param[0] = 0;
	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
	return -EIO;

	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
	return -EIO;

	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
	return -EIO;

	param[0] = reg;
	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
	return -EIO;

	if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
	return -EIO;

	return 0;
	}

	static int focaltech_read_size(struct psmouse *psmouse)
	{
	struct ps2dev *ps2dev = &psmouse->ps2dev;
	struct focaltech_data *priv = psmouse->private;
	char param[3];

	if (focaltech_read_register(ps2dev, 2, param))
	return -EIO;

	/* not sure whether this is 100% correct */
	priv->x_max = (unsigned char)param[1] * 128;
	priv->y_max = (unsigned char)param[2] * 128;

	return 0;
	}
	int focaltech_init(struct psmouse *psmouse)
	{
	struct focaltech_data *priv;
	int error;

	psmouse->private = priv = kzalloc(sizeof(struct focaltech_data),
	GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	focaltech_reset(psmouse);

	error = focaltech_read_size(psmouse);
	if (error) {
	psmouse_err(psmouse,
	"Unable to read the size of the touchpad\n");
	goto fail;
	}

	error = focaltech_switch_protocol(psmouse);
	if (error) {
	psmouse_err(psmouse, "Unable to initialize the device\n");
	goto fail;
	}

	focaltech_set_input_params(psmouse);

	psmouse->protocol_handler = focaltech_process_byte;
	psmouse->pktsize = 6;
	psmouse->disconnect = focaltech_disconnect;
	psmouse->reconnect = focaltech_reconnect;
	psmouse->cleanup = focaltech_reset;
	/* resync is not supported yet */
	psmouse->resync_time = 0;

	return 0;

	fail:
	focaltech_reset(psmouse);
	kfree(priv);
	return error;
	}

	#else /* CONFIG_MOUSE_PS2_FOCALTECH */

	int focaltech_init(struct psmouse *psmouse)
	{
	focaltech_reset(psmouse);

	return 0;
	}

	#endif /* CONFIG_MOUSE_PS2_FOCALTECH */