path: root/drivers/input/mouse/sentelic.c

/*-
 * Finger Sensing Pad PS/2 mouse driver.
 *
 * Copyright (C) 2005-2007 Asia Vital Components Co., Ltd.
 * Copyright (C) 2005-2012 Tai-hwa Liang, Sentelic Corporation.
 *
 *   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.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/module.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/ctype.h>
#include <linux/libps2.h>
#include <linux/serio.h>
#include <linux/jiffies.h>
#include <linux/slab.h>

#include "psmouse.h"
#include "sentelic.h"

/*
 * Timeout for FSP PS/2 command only (in milliseconds).
 */
#define	FSP_CMD_TIMEOUT		200
#define	FSP_CMD_TIMEOUT2	30

#define	GET_ABS_X(packet)	((packet[1] << 2) | ((packet[3] >> 2) & 0x03))
#define	GET_ABS_Y(packet)	((packet[2] << 2) | (packet[3] & 0x03))

/** Driver version. */
static const char fsp_drv_ver[] = "1.1.0-K";

/*
 * Make sure that the value being sent to FSP will not conflict with
 * possible sample rate values.
 */
static unsigned char fsp_test_swap_cmd(unsigned char reg_val)
{
	switch (reg_val) {
	case 10: case 20: case 40: case 60: case 80: case 100: case 200:
		/*
		 * The requested value being sent to FSP matched to possible
		 * sample rates, swap the given value such that the hardware
		 * wouldn't get confused.
		 */
		return (reg_val >> 4) | (reg_val << 4);
	default:
		return reg_val;	/* swap isn't necessary */
	}
}

/*
 * Make sure that the value being sent to FSP will not conflict with certain
 * commands.
 */
static unsigned char fsp_test_invert_cmd(unsigned char reg_val)
{
	switch (reg_val) {
	case 0xe9: case 0xee: case 0xf2: case 0xff:
		/*
		 * The requested value being sent to FSP matched to certain
		 * commands, inverse the given value such that the hardware
		 * wouldn't get confused.
		 */
		return ~reg_val;
	default:
		return reg_val;	/* inversion isn't necessary */
	}
}

static int fsp_reg_read(struct psmouse *psmouse, int reg_addr, int *reg_val)
{
	struct ps2dev *ps2dev = &psmouse->ps2dev;
	unsigned char param[3];
	unsigned char addr;
	int rc = -1;

	/*
	 * We need to shut off the device and switch it into command
	 * mode so we don't confuse our protocol handler. We don't need
	 * to do that for writes because sysfs set helper does this for
	 * us.
	 */
	psmouse_deactivate(psmouse);

	ps2_begin_command(ps2dev);

	if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
		goto out;

	/* should return 0xfe(request for resending) */
	ps2_sendbyte(ps2dev, 0x66, FSP_CMD_TIMEOUT2);
	/* should return 0xfc(failed) */
	ps2_sendbyte(ps2dev, 0x88, FSP_CMD_TIMEOUT2);

	if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
		goto out;

	if ((addr = fsp_test_invert_cmd(reg_addr)) != reg_addr) {
		ps2_sendbyte(ps2dev, 0x68, FSP_CMD_TIMEOUT2);
	} else if ((addr = fsp_test_swap_cmd(reg_addr)) != reg_addr) {
		/* swapping is required */
		ps2_sendbyte(ps2dev, 0xcc, FSP_CMD_TIMEOUT2);
		/* expect 0xfe */
	} else {
		/* swapping isn't necessary */
		ps2_sendbyte(ps2dev, 0x66, FSP_CMD_TIMEOUT2);
		/* expect 0xfe */
	}
	/* should return 0xfc(failed) */
	ps2_sendbyte(ps2dev, addr, FSP_CMD_TIMEOUT);

	if (__ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO) < 0)
		goto out;

	*reg_val = param[2];
	rc = 0;

 out:
	ps2_end_command(ps2dev);
	psmouse_activate(psmouse);
	psmouse_dbg(psmouse,
		    "READ REG: 0x%02x is 0x%02x (rc = %d)\n",
		    reg_addr, *reg_val, rc);
	return rc;
}

static int fsp_reg_write(struct psmouse *psmouse, int reg_addr, int reg_val)
{
	struct ps2dev *ps2dev = &psmouse->ps2dev;
	unsigned char v;
	int rc = -1;

	ps2_begin_command(ps2dev);

	if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
		goto out;

	if ((v = fsp_test_invert_cmd(reg_addr