Input: add new driver for Sentelic Finger Sensing Pad

This is the driver for Sentelic Finger Sensing Pad which can be found
on MSI WIND Netbook.

Signed-off-by: Tai-hwa Liang <avatar@sentelic.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/mouse/sentelic.c b/drivers/input/mouse/sentelic.c
new file mode 100644
index 0000000..97b1e72
--- /dev/null
+++ b/drivers/input/mouse/sentelic.c
@@ -0,0 +1,867 @@
+/*-
+ * Finger Sensing Pad PS/2 mouse driver.
+ *
+ * Copyright (C) 2005-2007 Asia Vital Components Co., Ltd.
+ * Copyright (C) 2005-2009 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/version.h>
+#include <linux/input.h>
+#include <linux/ctype.h>
+#include <linux/libps2.h>
+#include <linux/serio.h>
+#include <linux/jiffies.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
+
+/** Driver version. */
+static const char fsp_drv_ver[] = "1.0.0-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.
+	 */
+	ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE);
+	psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
+	mutex_lock(&ps2dev->cmd_mutex);
+
+	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:
+	mutex_unlock(&ps2dev->cmd_mutex);
+	ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE);
+	psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
+	dev_dbg(&ps2dev->serio->dev, "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;
+
+	mutex_lock(&ps2dev->cmd_mutex);
+
+	if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
+		goto out;
+
+	if ((v = fsp_test_invert_cmd(reg_addr)) != reg_addr) {
+		/* inversion is required */
+		ps2_sendbyte(ps2dev, 0x74, FSP_CMD_TIMEOUT2);
+	} else {
+		if ((v = fsp_test_swap_cmd(reg_addr)) != reg_addr) {
+			/* swapping is required */
+			ps2_sendbyte(ps2dev, 0x77, FSP_CMD_TIMEOUT2);
+		} else {
+			/* swapping isn't necessary */
+			ps2_sendbyte(ps2dev, 0x55, FSP_CMD_TIMEOUT2);
+		}
+	}
+	/* write the register address in correct order */
+	ps2_sendbyte(ps2dev, v, FSP_CMD_TIMEOUT2);
+
+	if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
+		return -1;
+
+	if ((v = fsp_test_invert_cmd(reg_val)) != reg_val) {
+		/* inversion is required */
+		ps2_sendbyte(ps2dev, 0x47, FSP_CMD_TIMEOUT2);
+	} else if ((v = fsp_test_swap_cmd(reg_val)) != reg_val) {
+		/* swapping is required */
+		ps2_sendbyte(ps2dev, 0x44, FSP_CMD_TIMEOUT2);
+	} else {
+		/* swapping isn't necessary */
+		ps2_sendbyte(ps2dev, 0x33, FSP_CMD_TIMEOUT2);
+	}
+
+	/* write the register value in correct order */
+	ps2_sendbyte(ps2dev, v, FSP_CMD_TIMEOUT2);
+	rc = 0;
+
+ out:
+	mutex_unlock(&ps2dev->cmd_mutex);
+	dev_dbg(&ps2dev->serio->dev, "WRITE REG: 0x%02x to 0x%02x (rc = %d)\n",
+		reg_addr, reg_val, rc);
+	return rc;
+}
+
+/* Enable register clock gating for writing certain registers */
+static int fsp_reg_write_enable(struct psmouse *psmouse, bool enable)
+{
+	int v, nv;
+
+	if (fsp_reg_read(psmouse, FSP_REG_SYSCTL1, &v) == -1)
+		return -1;
+
+	if (enable)
+		nv = v | FSP_BIT_EN_REG_CLK;
+	else
+		nv = v & ~FSP_BIT_EN_REG_CLK;
+
+	/* only write if necessary */
+	if (nv != v)
+		if (fsp_reg_write(psmouse, FSP_REG_SYSCTL1, nv) == -1)
+			return -1;
+
+	return 0;
+}
+
+static int fsp_page_reg_read(struct psmouse *psmouse, int *reg_val)
+{
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+	unsigned char param[3];
+	int rc = -1;
+
+	ps2_command(ps2dev, NULL, PSMOUSE_CMD_DISABLE);
+	psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
+	mutex_lock(&ps2dev->cmd_mutex);
+
+	if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
+		goto out;
+
+	ps2_sendbyte(ps2dev, 0x66, FSP_CMD_TIMEOUT2);
+	ps2_sendbyte(ps2dev, 0x88, FSP_CMD_TIMEOUT2);
+
+	if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
+		goto out;
+
+	ps2_sendbyte(ps2dev, 0x83, FSP_CMD_TIMEOUT2);
+	ps2_sendbyte(ps2dev, 0x88, FSP_CMD_TIMEOUT2);
+
+	/* get the returned result */
+	if (__ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
+		goto out;
+
+	*reg_val = param[2];
+	rc = 0;
+
+ out:
+	mutex_unlock(&ps2dev->cmd_mutex);
+	ps2_command(ps2dev, NULL, PSMOUSE_CMD_ENABLE);
+	psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
+	dev_dbg(&ps2dev->serio->dev, "READ PAGE REG: 0x%02x (rc = %d)\n",
+		*reg_val, rc);
+	return rc;
+}
+
+static int fsp_page_reg_write(struct psmouse *psmouse, int reg_val)
+{
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+	unsigned char v;
+	int rc = -1;
+
+	mutex_lock(&ps2dev->cmd_mutex);
+
+	if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
+		goto out;
+
+	ps2_sendbyte(ps2dev, 0x38, FSP_CMD_TIMEOUT2);
+	ps2_sendbyte(ps2dev, 0x88, FSP_CMD_TIMEOUT2);
+
+	if (ps2_sendbyte(ps2dev, 0xf3, FSP_CMD_TIMEOUT) < 0)
+		return -1;
+
+	if ((v = fsp_test_invert_cmd(reg_val)) != reg_val) {
+		ps2_sendbyte(ps2dev, 0x47, FSP_CMD_TIMEOUT2);
+	} else if ((v = fsp_test_swap_cmd(reg_val)) != reg_val) {
+		/* swapping is required */
+		ps2_sendbyte(ps2dev, 0x44, FSP_CMD_TIMEOUT2);
+	} else {
+		/* swapping isn't necessary */
+		ps2_sendbyte(ps2dev, 0x33, FSP_CMD_TIMEOUT2);
+	}
+
+	ps2_sendbyte(ps2dev, v, FSP_CMD_TIMEOUT2);
+	rc = 0;
+
+ out:
+	mutex_unlock(&ps2dev->cmd_mutex);
+	dev_dbg(&ps2dev->serio->dev, "WRITE PAGE REG: to 0x%02x (rc = %d)\n",
+		reg_val, rc);
+	return rc;
+}
+
+static int fsp_get_version(struct psmouse *psmouse, int *version)
+{
+	if (fsp_reg_read(psmouse, FSP_REG_VERSION, version))
+		return -EIO;
+
+	return 0;
+}
+
+static int fsp_get_revision(struct psmouse *psmouse, int *rev)
+{
+	if (fsp_reg_read(psmouse, FSP_REG_REVISION, rev))
+		return -EIO;
+
+	return 0;
+}
+
+static int fsp_get_buttons(struct psmouse *psmouse, int *btn)
+{
+	static const int buttons[] = {
+		0x16, /* Left/Middle/Right/Forward/Backward & Scroll Up/Down */
+		0x06, /* Left/Middle/Right & Scroll Up/Down/Right/Left */
+		0x04, /* Left/Middle/Right & Scroll Up/Down */
+		0x02, /* Left/Middle/Right */
+	};
+	int val;
+
+	if (fsp_reg_read(psmouse, FSP_REG_TMOD_STATUS1, &val) == -1)
+		return -EIO;
+
+	*btn = buttons[(val & 0x30) >> 4];
+	return 0;
+}
+
+/* Enable on-pad command tag output */
+static int fsp_opc_tag_enable(struct psmouse *psmouse, bool enable)
+{
+	int v, nv;
+	int res = 0;
+
+	if (fsp_reg_read(psmouse, FSP_REG_OPC_QDOWN, &v) == -1) {
+		dev_err(&psmouse->ps2dev.serio->dev, "Unable get OPC state.\n");
+		return -EIO;
+	}
+
+	if (enable)
+		nv = v | FSP_BIT_EN_OPC_TAG;
+	else
+		nv = v & ~FSP_BIT_EN_OPC_TAG;
+
+	/* only write if necessary */
+	if (nv != v) {
+		fsp_reg_write_enable(psmouse, true);
+		res = fsp_reg_write(psmouse, FSP_REG_OPC_QDOWN, nv);
+		fsp_reg_write_enable(psmouse, false);
+	}
+
+	if (res != 0) {
+		dev_err(&psmouse->ps2dev.serio->dev,
+			"Unable to enable OPC tag.\n");
+		res = -EIO;
+	}
+
+	return res;
+}
+
+static int fsp_onpad_vscr(struct psmouse *psmouse, bool enable)
+{
+	struct fsp_data *pad = psmouse->private;
+	int val;
+
+	if (fsp_reg_read(psmouse, FSP_REG_ONPAD_CTL, &val))
+		return -EIO;
+
+	pad->vscroll = enable;
+
+	if (enable)
+		val |= (FSP_BIT_FIX_VSCR | FSP_BIT_ONPAD_ENABLE);
+	else
+		val &= ~FSP_BIT_FIX_VSCR;
+
+	if (fsp_reg_write(psmouse, FSP_REG_ONPAD_CTL, val))
+		return -EIO;
+
+	return 0;
+}
+
+static int fsp_onpad_hscr(struct psmouse *psmouse, bool enable)
+{
+	struct fsp_data *pad = psmouse->private;
+	int val, v2;
+
+	if (fsp_reg_read(psmouse, FSP_REG_ONPAD_CTL, &val))
+		return -EIO;
+
+	if (fsp_reg_read(psmouse, FSP_REG_SYSCTL5, &v2))
+		return -EIO;
+
+	pad->hscroll = enable;
+
+	if (enable) {
+		val |= (FSP_BIT_FIX_HSCR | FSP_BIT_ONPAD_ENABLE);
+		v2 |= FSP_BIT_EN_MSID6;
+	} else {
+		val &= ~FSP_BIT_FIX_HSCR;
+		v2 &= ~(FSP_BIT_EN_MSID6 | FSP_BIT_EN_MSID7 | FSP_BIT_EN_MSID8);
+	}
+
+	if (fsp_reg_write(psmouse, FSP_REG_ONPAD_CTL, val))
+		return -EIO;
+
+	/* reconfigure horizontal scrolling packet output */
+	if (fsp_reg_write(psmouse, FSP_REG_SYSCTL5, v2))
+		return -EIO;
+
+	return 0;
+}
+
+/*
+ * Write device specific initial parameters.
+ *
+ * ex: 0xab 0xcd - write oxcd into register 0xab
+ */
+static ssize_t fsp_attr_set_setreg(struct psmouse *psmouse, void *data,
+				   const char *buf, size_t count)
+{
+	unsigned long reg, val;
+	char *rest;
+	ssize_t retval;
+
+	reg = simple_strtoul(buf, &rest, 16);
+	if (rest == buf || *rest != ' ' || reg > 0xff)
+		return -EINVAL;
+
+	if (strict_strtoul(rest + 1, 16, &val) || val > 0xff)
+		return -EINVAL;
+
+	if (fsp_reg_write_enable(psmouse, true))
+		return -EIO;
+
+	retval = fsp_reg_write(psmouse, reg, val) < 0 ? -EIO : count;
+
+	fsp_reg_write_enable(psmouse, false);
+
+	return count;
+}
+
+PSMOUSE_DEFINE_WO_ATTR(setreg, S_IWUSR, NULL, fsp_attr_set_setreg);
+
+static ssize_t fsp_attr_show_getreg(struct psmouse *psmouse,
+					void *data, char *buf)
+{
+	struct fsp_data *pad = psmouse->private;
+
+	return sprintf(buf, "%02x%02x\n", pad->last_reg, pad->last_val);
+}
+
+/*
+ * Read a register from device.
+ *
+ * ex: 0xab -- read content from register 0xab
+ */
+static ssize_t fsp_attr_set_getreg(struct psmouse *psmouse, void *data,
+					const char *buf, size_t count)
+{
+	struct fsp_data *pad = psmouse->private;
+	unsigned long reg;
+	int val;
+
+	if (strict_strtoul(buf, 16, &reg) || reg > 0xff)
+		return -EINVAL;
+
+	if (fsp_reg_read(psmouse, reg, &val))
+		return -EIO;
+
+	pad->last_reg = reg;
+	pad->last_val = val;
+
+	return count;
+}
+
+PSMOUSE_DEFINE_ATTR(getreg, S_IWUSR | S_IRUGO, NULL,
+			fsp_attr_show_getreg, fsp_attr_set_getreg);
+
+static ssize_t fsp_attr_show_pagereg(struct psmouse *psmouse,
+					void *data, char *buf)
+{
+	int val = 0;
+
+	if (fsp_page_reg_read(psmouse, &val))
+		return -EIO;
+
+	return sprintf(buf, "%02x\n", val);
+}
+
+static ssize_t fsp_attr_set_pagereg(struct psmouse *psmouse, void *data,
+					const char *buf, size_t count)
+{
+	unsigned long val;
+
+	if (strict_strtoul(buf, 16, &val) || val > 0xff)
+		return -EINVAL;
+
+	if (fsp_page_reg_write(psmouse, val))
+		return -EIO;
+
+	return count;
+}
+
+PSMOUSE_DEFINE_ATTR(page, S_IWUSR | S_IRUGO, NULL,
+			fsp_attr_show_pagereg, fsp_attr_set_pagereg);
+
+static ssize_t fsp_attr_show_vscroll(struct psmouse *psmouse,
+					void *data, char *buf)
+{
+	struct fsp_data *pad = psmouse->private;
+
+	return sprintf(buf, "%d\n", pad->vscroll);
+}
+
+static ssize_t fsp_attr_set_vscroll(struct psmouse *psmouse, void *data,
+					const char *buf, size_t count)
+{
+	unsigned long val;
+
+	if (strict_strtoul(buf, 10, &val) || val > 1)
+		return -EINVAL;
+
+	fsp_onpad_vscr(psmouse, val);
+
+	return count;
+}
+
+PSMOUSE_DEFINE_ATTR(vscroll, S_IWUSR | S_IRUGO, NULL,
+			fsp_attr_show_vscroll, fsp_attr_set_vscroll);
+
+static ssize_t fsp_attr_show_hscroll(struct psmouse *psmouse,
+					void *data, char *buf)
+{
+	struct fsp_data *pad = psmouse->private;
+
+	return sprintf(buf, "%d\n", pad->hscroll);
+}
+
+static ssize_t fsp_attr_set_hscroll(struct psmouse *psmouse, void *data,
+					const char *buf, size_t count)
+{
+	unsigned long val;
+
+	if (strict_strtoul(buf, 10, &val) || val > 1)
+		return -EINVAL;
+
+	fsp_onpad_hscr(psmouse, val);
+
+	return count;
+}
+
+PSMOUSE_DEFINE_ATTR(hscroll, S_IWUSR | S_IRUGO, NULL,
+			fsp_attr_show_hscroll, fsp_attr_set_hscroll);
+
+static ssize_t fsp_attr_show_flags(struct psmouse *psmouse,
+					void *data, char *buf)
+{
+	struct fsp_data *pad = psmouse->private;
+
+	return sprintf(buf, "%c\n",
+			pad->flags & FSPDRV_FLAG_EN_OPC ? 'C' : 'c');
+}
+
+static ssize_t fsp_attr_set_flags(struct psmouse *psmouse, void *data,
+					const char *buf, size_t count)
+{
+	struct fsp_data *pad = psmouse->private;
+	size_t i;
+
+	for (i = 0; i < count; i++) {
+		switch (buf[i]) {
+		case 'C':
+			pad->flags |= FSPDRV_FLAG_EN_OPC;
+			break;
+		case 'c':
+			pad->flags &= ~FSPDRV_FLAG_EN_OPC;
+			break;
+		default:
+			return -EINVAL;
+		}
+	}
+	return count;
+}
+
+PSMOUSE_DEFINE_ATTR(flags, S_IWUSR | S_IRUGO, NULL,
+			fsp_attr_show_flags, fsp_attr_set_flags);
+
+static ssize_t fsp_attr_show_ver(struct psmouse *psmouse,
+					void *data, char *buf)
+{
+	return sprintf(buf, "Sentelic FSP kernel module %s\n", fsp_drv_ver);
+}
+
+PSMOUSE_DEFINE_RO_ATTR(ver, S_IRUGO, NULL, fsp_attr_show_ver);
+
+static struct attribute *fsp_attributes[] = {
+	&psmouse_attr_setreg.dattr.attr,
+	&psmouse_attr_getreg.dattr.attr,
+	&psmouse_attr_page.dattr.attr,
+	&psmouse_attr_vscroll.dattr.attr,
+	&psmouse_attr_hscroll.dattr.attr,
+	&psmouse_attr_flags.dattr.attr,
+	&psmouse_attr_ver.dattr.attr,
+	NULL
+};
+
+static struct attribute_group fsp_attribute_group = {
+	.attrs = fsp_attributes,
+};
+
+#ifdef FSP_DEBUG
+static void fsp_packet_debug(unsigned char packet[])
+{
+	static unsigned int ps2_packet_cnt;
+	static unsigned int ps2_last_second;
+	unsigned int jiffies_msec;
+
+	ps2_packet_cnt++;
+	jiffies_msec = jiffies_to_msecs(jiffies);
+	printk(KERN_DEBUG "%08dms PS/2 packets: %02x, %02x, %02x, %02x\n",
+		jiffies_msec, packet[0], packet[1], packet[2], packet[3]);
+
+	if (jiffies_msec - ps2_last_second > 1000) {
+		printk(KERN_DEBUG "PS/2 packets/sec = %d\n", ps2_packet_cnt);
+		ps2_packet_cnt = 0;
+		ps2_last_second = jiffies_msec;
+	}
+}
+#else
+static void fsp_packet_debug(unsigned char packet[])
+{
+}
+#endif
+
+static psmouse_ret_t fsp_process_byte(struct psmouse *psmouse)
+{
+	struct input_dev *dev = psmouse->dev;
+	struct fsp_data *ad = psmouse->private;
+	unsigned char *packet = psmouse->packet;
+	unsigned char button_status = 0, lscroll = 0, rscroll = 0;
+	int rel_x, rel_y;
+
+	if (psmouse->pktcnt < 4)
+		return PSMOUSE_GOOD_DATA;
+
+	/*
+	 * Full packet accumulated, process it
+	 */
+
+	switch (psmouse->packet[0] >> FSP_PKT_TYPE_SHIFT) {
+	case FSP_PKT_TYPE_ABS:
+		dev_warn(&psmouse->ps2dev.serio->dev,
+			 "Unexpected absolute mode packet, ignored.\n");
+		break;
+
+	case FSP_PKT_TYPE_NORMAL_OPC:
+		/* on-pad click, filter it if necessary */
+		if ((ad->flags & FSPDRV_FLAG_EN_OPC) != FSPDRV_FLAG_EN_OPC)
+			packet[0] &= ~BIT(0);
+		/* fall through */
+
+	case FSP_PKT_TYPE_NORMAL:
+		/* normal packet */
+		/* special packet data translation from on-pad packets */
+		if (packet[3] != 0) {
+			if (packet[3] & BIT(0))
+				button_status |= 0x01;	/* wheel down */
+			if (packet[3] & BIT(1))
+				button_status |= 0x0f;	/* wheel up */
+			if (packet[3] & BIT(2))
+				button_status |= BIT(5);/* horizontal left */
+			if (packet[3] & BIT(3))
+				button_status |= BIT(4);/* horizontal right */
+			/* push back to packet queue */
+			if (button_status != 0)
+				packet[3] = button_status;
+			rscroll = (packet[3] >> 4) & 1;
+			lscroll = (packet[3] >> 5) & 1;
+		}
+		/*
+		 * Processing wheel up/down and extra button events
+		 */
+		input_report_rel(dev, REL_WHEEL,
+				 (int)(packet[3] & 8) - (int)(packet[3] & 7));
+		input_report_rel(dev, REL_HWHEEL, lscroll - rscroll);
+		input_report_key(dev, BTN_BACK, lscroll);
+		input_report_key(dev, BTN_FORWARD, rscroll);
+
+		/*
+		 * Standard PS/2 Mouse
+		 */
+		input_report_key(dev, BTN_LEFT, packet[0] & 1);
+		input_report_key(dev, BTN_MIDDLE, (packet[0] >> 2) & 1);
+		input_report_key(dev, BTN_RIGHT, (packet[0] >> 1) & 1);
+
+		rel_x = packet[1] ? (int)packet[1] - (int)((packet[0] << 4) & 0x100) : 0;
+		rel_y = packet[2] ? (int)((packet[0] << 3) & 0x100) - (int)packet[2] : 0;
+
+		input_report_rel(dev, REL_X, rel_x);
+		input_report_rel(dev, REL_Y, rel_y);
+		break;
+	}
+
+	input_sync(dev);
+
+	fsp_packet_debug(packet);
+
+	return PSMOUSE_FULL_PACKET;
+}
+
+static int fsp_activate_protocol(struct psmouse *psmouse)
+{
+	struct fsp_data *pad = psmouse->private;
+	struct ps2dev *ps2dev = &psmouse->ps2dev;
+	unsigned char param[2];
+	int val;
+
+	/*
+	 * Standard procedure to enter FSP Intellimouse mode
+	 * (scrolling wheel, 4th and 5th buttons)
+	 */
+	param[0] = 200;
+	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
+	param[0] = 200;
+	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
+	param[0] =  80;
+	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
+
+	ps2_command(ps2dev, param, PSMOUSE_CMD_GETID);
+	if (param[0] != 0x04) {
+		dev_err(&psmouse->ps2dev.serio->dev,
+			"Unable to enable 4 bytes packet format.\n");
+		return -EIO;
+	}
+
+	if (fsp_reg_read(psmouse, FSP_REG_SYSCTL5, &val)) {
+		dev_err(&psmouse->ps2dev.serio->dev,
+			"Unable to read SYSCTL5 register.\n");
+		return -EIO;
+	}
+
+	val &= ~(FSP_BIT_EN_MSID7 | FSP_BIT_EN_MSID8 | FSP_BIT_EN_AUTO_MSID8);
+	/* Ensure we are not in absolute mode */
+	val &= ~FSP_BIT_EN_PKT_G0;
+	if (pad->buttons == 0x06) {
+		/* Left/Middle/Right & Scroll Up/Down/Right/Left */
+		val |= FSP_BIT_EN_MSID6;
+	}
+
+	if (fsp_reg_write(psmouse, FSP_REG_SYSCTL5, val)) {
+		dev_err(&psmouse->ps2dev.serio->dev,
+			"Unable to set up required mode bits.\n");
+		return -EIO;
+	}
+
+	/*
+	 * Enable OPC tags such that driver can tell the difference between
+	 * on-pad and real button click
+	 */
+	if (fsp_opc_tag_enable(psmouse, true))
+		dev_warn(&psmouse->ps2dev.serio->dev,
+			 "Failed to enable OPC tag mode.\n");
+
+	/* Enable on-pad vertical and horizontal scrolling */
+	fsp_onpad_vscr(psmouse, true);
+	fsp_onpad_hscr(psmouse, true);
+
+	return 0;
+}
+
+int fsp_detect(struct psmouse *psmouse, int set_properties)
+{
+	int id;
+
+	if (fsp_reg_read(psmouse, FSP_REG_DEVICE_ID, &id))
+		return -EIO;
+
+	if (id != 0x01)
+		return -ENODEV;
+
+	if (set_properties) {
+		psmouse->vendor = "Sentelic";
+		psmouse->name = "FingerSensingPad";
+	}
+
+	return 0;
+}
+
+static void fsp_reset(struct psmouse *psmouse)
+{
+	fsp_opc_tag_enable(psmouse, false);
+	fsp_onpad_vscr(psmouse, false);
+	fsp_onpad_hscr(psmouse, false);
+}
+
+static void fsp_disconnect(struct psmouse *psmouse)
+{
+	sysfs_remove_group(&psmouse->ps2dev.serio->dev.kobj,
+			   &fsp_attribute_group);
+
+	fsp_reset(psmouse);
+	kfree(psmouse->private);
+}
+
+static int fsp_reconnect(struct psmouse *psmouse)
+{
+	int version;
+
+	if (fsp_detect(psmouse, 0))
+		return -ENODEV;
+
+	if (fsp_get_version(psmouse, &version))
+		return -ENODEV;
+
+	if (fsp_activate_protocol(psmouse))
+		return -EIO;
+
+	return 0;
+}
+
+int fsp_init(struct psmouse *psmouse)
+{
+	struct fsp_data *priv;
+	int ver, rev, buttons;
+	int error;
+
+	if (fsp_get_version(psmouse, &ver) ||
+	    fsp_get_revision(psmouse, &rev) ||
+	    fsp_get_buttons(psmouse, &buttons)) {
+		return -ENODEV;
+	}
+
+	printk(KERN_INFO
+		"Finger Sensing Pad, hw: %d.%d.%d, sw: %s, buttons: %d\n",
+		ver >> 4, ver & 0x0F, rev, fsp_drv_ver, buttons & 7);
+
+	psmouse->private = priv = kzalloc(sizeof(struct fsp_data), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->ver = ver;
+	priv->rev = rev;
+	priv->buttons = buttons;
+
+	/* enable on-pad click by default */
+	priv->flags |= FSPDRV_FLAG_EN_OPC;
+
+	/* Set up various supported input event bits */
+	__set_bit(BTN_BACK, psmouse->dev->keybit);
+	__set_bit(BTN_FORWARD, psmouse->dev->keybit);
+	__set_bit(REL_WHEEL, psmouse->dev->relbit);
+	__set_bit(REL_HWHEEL, psmouse->dev->relbit);
+
+	psmouse->protocol_handler = fsp_process_byte;
+	psmouse->disconnect = fsp_disconnect;
+	psmouse->reconnect = fsp_reconnect;
+	psmouse->cleanup = fsp_reset;
+	psmouse->pktsize = 4;
+
+	/* set default packet output based on number of buttons we found */
+	error = fsp_activate_protocol(psmouse);
+	if (error)
+		goto err_out;
+
+	error = sysfs_create_group(&psmouse->ps2dev.serio->dev.kobj,
+				   &fsp_attribute_group);
+	if (error) {
+		dev_err(&psmouse->ps2dev.serio->dev,
+			"Failed to create sysfs attributes (%d)", error);
+		goto err_out;
+	}
+
+	return 0;
+
+ err_out:
+	kfree(psmouse->private);
+	psmouse->private = NULL;
+	return error;
+}