drivers/input/keyboard/atkbd.c

/*
 * AT and PS/2 keyboard driver
 *
 * Copyright (c) 1999-2002 Vojtech Pavlik
 */

/*
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

/*
 * This driver can handle standard AT keyboards and PS/2 keyboards in
 * Translated and Raw Set 2 and Set 3, as well as AT keyboards on dumb
 * input-only controllers and AT keyboards connected over a one way RS232
 * converter.
 */

#include <linux/delay.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/serio.h>
#include <linux/workqueue.h>
#include <linux/libps2.h>
#include <linux/mutex.h>

#define DRIVER_DESC	"AT and PS/2 keyboard driver"

MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

static int atkbd_set = 2;
module_param_named(set, atkbd_set, int, 0);
MODULE_PARM_DESC(set, "Select keyboard code set (2 = default, 3 = PS/2 native)");

#if defined(__i386__) || defined(__x86_64__) || defined(__hppa__)
static int atkbd_reset;
#else
static int atkbd_reset = 1;
#endif
module_param_named(reset, atkbd_reset, bool, 0);
MODULE_PARM_DESC(reset, "Reset keyboard during initialization");

static int atkbd_softrepeat;
module_param_named(softrepeat, atkbd_softrepeat, bool, 0);
MODULE_PARM_DESC(softrepeat, "Use software keyboard repeat");

static int atkbd_softraw = 1;
module_param_named(softraw, atkbd_softraw, bool, 0);
MODULE_PARM_DESC(softraw, "Use software generated rawmode");

static int atkbd_scroll;
module_param_named(scroll, atkbd_scroll, bool, 0);
MODULE_PARM_DESC(scroll, "Enable scroll-wheel on MS Office and similar keyboards");

static int atkbd_extra;
module_param_named(extra, atkbd_extra, bool, 0);
MODULE_PARM_DESC(extra, "Enable extra LEDs and keys on IBM RapidAcces, EzKey and similar keyboards");

/*
 * Scancode to keycode tables. These are just the default setting, and
 * are loadable via an userland utility.
 */

static unsigned char atkbd_set2_keycode[512] = {

#ifdef CONFIG_KEYBOARD_ATKBD_HP_KEYCODES

/* XXX: need a more general approach */

#include "hpps2atkbd.h"	/* include the keyboard scancodes */

#else
	  0, 67, 65, 63, 61, 59, 60, 88,  0, 68, 66, 64, 62, 15, 41,117,
	  0, 56, 42, 93, 29, 16,  2,  0,  0,  0, 44, 31, 30, 17,  3,  0,
	  0, 46, 45, 32, 18,  5,  4, 95,  0, 57, 47, 33, 20, 19,  6,183,
	  0, 49, 48, 35, 34, 21,  7,184,  0,  0, 50, 36, 22,  8,  9,185,
	  0, 51, 37, 23, 24, 11, 10,  0,  0, 52, 53, 38, 39, 25, 12,  0,
	  0, 89, 40,  0, 26, 13,  0,  0, 58, 54, 28, 27,  0, 43,  0, 85,
	  0, 86, 91, 90, 92,  0, 14, 94,  0, 79,124, 75, 71,121,  0,  0,
	 82, 83, 80, 76, 77, 72,  1, 69, 87, 78, 81, 74, 55, 73, 70, 99,

	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
	217,100,255,  0, 97,165,  0,  0,156,  0,  0,  0,  0,  0,  0,125,
	173,114,  0,113,  0,  0,  0,126,128,  0,  0,140,  0,  0,  0,127,
	159,  0,115,  0,164,  0,  0,116,158,  0,150,166,  0,  0,  0,142,
	157,  0,  0,  0,  0,  0,  0,  0,155,  0, 98,  0,  0,163,  0,  0,
	226,  0,  0,  0,  0,  0,  0,  0,  0,255, 96,  0,  0,  0,143,  0,
	  0,  0,  0,  0,  0,  0,  0,  0,  0,107,  0,105,102,  0,  0,112,
	110,111,108,112,106,103,  0,119,  0,118,109,  0, 99,104,119,  0,

	  0,  0,  0, 65, 99,
#endif
};

static unsigned char atkbd_set3_keycode[512] = {

	  0,  0,  0,  0,  0,  0,  0, 59,  1,138,128,129,130, 15, 41, 60,
	131, 29, 42, 86, 58, 16,  2, 61,133, 56, 44, 31, 30, 17,  3, 62,
	134, 46, 45, 32, 18,  5,  4, 63,135, 57, 47, 33, 20, 19,  6, 64,
	136, 49, 48, 35, 34, 21,  7, 65,137,100, 50, 36, 22,  8,  9, 66,
	125, 51, 37, 23, 24, 11, 10, 67,126, 52, 53, 38, 39, 25, 12, 68,
	113,114, 40, 43, 26, 13, 87, 99, 97, 54, 28, 27, 43, 43, 88, 70,
	108,105,119,103,111,107, 14,110,  0, 79,106, 75, 71,109,102,104,
	 82, 83, 80, 76, 77, 72, 69, 98,  0, 96, 81,  0, 78, 73, 55,183,

	184,185,186,187, 74, 94, 92, 93,  0,  0,  0,125,126,127,112,  0,
	  0,139,150,163,165,115,152,150,166,140,160,154,113,114,167,168,
	148,149,147,140
};

static unsigned char atkbd_unxlate_table[128] = {
          0,118, 22, 30, 38, 37, 46, 54, 61, 62, 70, 69, 78, 85,102, 13,
         21, 29, 36, 45, 44, 53, 60, 67, 68, 77, 84, 91, 90, 20, 28, 27,
         35, 43, 52, 51, 59, 66, 75, 76, 82, 14, 18, 93, 26, 34, 33, 42,
         50, 49, 58, 65, 73, 74, 89,124, 17, 41, 88,  5,  6,  4, 12,  3,
         11,  2, 10,  1,  9,119,126,108,117,125,123,107,115,116,121,105,
        114,122,112,113,127, 96, 97,120,  7, 15, 23, 31, 39, 47, 55, 63,
         71, 79, 86, 94,  8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 87,111,
         19, 25, 57, 81, 83, 92, 95, 98, 99,100,101,103,104,106,109,110
};

#define ATKBD_CMD_SETLEDS	0x10ed
#define ATKBD_CMD_GSCANSET	0x11f0
#define ATKBD_CMD_SSCANSET	0x10f0
#define ATKBD_CMD_GETID		0x02f2
#define ATKBD_CMD_SETREP	0x10f3
#define ATKBD_CMD_ENABLE	0x00f4
#define ATKBD_CMD_RESET_DIS	0x00f5
#define ATKBD_CMD_SETALL_MBR	0x00fa
#define ATKBD_CMD_RESET_BAT	0x02ff
#define ATKBD_CMD_RESEND	0x00fe
#define ATKBD_CMD_EX_ENABLE	0x10ea
#define ATKBD_CMD_EX_SETLEDS	0x20eb
#define ATKBD_CMD_OK_GETID	0x02e8

#define ATKBD_RET_ACK		0xfa
#define ATKBD_RET_NAK		0xfe
#define ATKBD_RET_BAT		0xaa
#define ATKBD_RET_EMUL0		0xe0
#define ATKBD_RET_EMUL1		0xe1
#define ATKBD_RET_RELEASE	0xf0
#define ATKBD_RET_HANJA		0xf1
#define ATKBD_RET_HANGEUL	0xf2
#define ATKBD_RET_ERR		0xff

#define ATKBD_KEY_UNKNOWN	  0
#define ATKBD_KEY_NULL		255

#define ATKBD_SCR_1		254
#define ATKBD_SCR_2		253
#define ATKBD_SCR_4		252
#define ATKBD_SCR_8		251
#define ATKBD_SCR_CLICK		250
#define ATKBD_SCR_LEFT		249
#define ATKBD_SCR_RIGHT		248

#define ATKBD_SPECIAL		248

#define ATKBD_LED_EVENT_BIT	0
#define ATKBD_REP_EVENT_BIT	1

#define ATKBD_XL_ERR		0x01
#define ATKBD_XL_BAT		0x02
#define ATKBD_XL_ACK		0x04
#define ATKBD_XL_NAK		0x08
#define ATKBD_XL_HANGEUL	0x10
#define ATKBD_XL_HANJA		0x20

static struct {
	unsigned char keycode;
	unsigned char set2;
} atkbd_scroll_keys[] = {
	{ ATKBD_SCR_1,     0xc5 },
	{ ATKBD_SCR_2,     0x9d },
	{ ATKBD_SCR_4,     0xa4 },
	{ ATKBD_SCR_8,     0x9b },
	{ ATKBD_SCR_CLICK, 0xe0 },
	{ ATKBD_SCR_LEFT,  0xcb },
	{ ATKBD_SCR_RIGHT, 0xd2 },
};

/*
 * The atkbd control structure
 */

struct atkbd {

	struct ps2dev ps2dev;
	struct input_dev *dev;

	/* Written only during init */
	char name[64];
	char phys[32];

	unsigned short id;
	unsigned char keycode[512];
	unsigned char set;
	unsigned char translated;
	unsigned char extra;
	unsigned char write;
	unsigned char softrepeat;
	unsigned char softraw;
	unsigned char scroll;
	unsigned char enabled;

	/* Accessed only from interrupt */
	unsigned char emul;
	unsigned char resend;
	unsigned char release;
	unsigned long xl_bit;
	unsigned int last;
	unsigned long time;
	unsigned long err_count;

	struct delayed_work event_work;
	unsigned long event_jiffies;
	struct mutex event_mutex;
	unsigned long event_mask;
};

static ssize_t atkbd_attr_show_helper(struct device *dev, char *buf,
				ssize_t (*handler)(struct atkbd *, char *));
static ssize_t atkbd_attr_set_helper(struct device *dev, const char *buf, size_t count,
				ssize_t (*handler)(struct atkbd *, const char *, size_t));
#define ATKBD_DEFINE_ATTR(_name)						\
static ssize_t atkbd_show_##_name(struct atkbd *, char *);			\
static ssize_t atkbd_set_##_name(struct atkbd *, const char *, size_t);		\
static ssize_t atkbd_do_show_##_name(struct device *d,				\
				struct device_attribute *attr, char *b)		\
{										\
	return atkbd_attr_show_helper(d, b, atkbd_show_##_name);		\
}										\
static ssize_t atkbd_do_set_##_name(struct device *d,				\
			struct device_attribute *attr, const char *b, size_t s)	\
{										\
	return atkbd_attr_set_helper(d, b, s, atkbd_set_##_name);		\
}										\
static struct device_attribute atkbd_attr_##_name =				\
	__ATTR(_name, S_IWUSR | S_IRUGO, atkbd_do_show_##_name, atkbd_do_set_##_name);

ATKBD_DEFINE_ATTR(extra);
ATKBD_DEFINE_ATTR(scroll);
ATKBD_DEFINE_ATTR(set);
ATKBD_DEFINE_ATTR(softrepeat);
ATKBD_DEFINE_ATTR(softraw);

#define ATKBD_DEFINE_RO_ATTR(_name)						\
static ssize_t atkbd_show_##_name(struct atkbd *, char *);			\
static ssize_t atkbd_do_show_##_name(struct device *d,				\
				struct device_attribute *attr, char *b)		\
{										\
	return atkbd_attr_show_helper(d, b, atkbd_show_##_name);		\
}										\
static struct device_attribute atkbd_attr_##_name =				\
	__ATTR(_name, S_IRUGO, atkbd_do_show_##_name, NULL);

ATKBD_DEFINE_RO_ATTR(err_count);

static struct attribute *atkbd_attributes[] = {
	&atkbd_attr_extra.attr,
	&atkbd_attr_scroll.attr,
	&atkbd_attr_set.attr,
	&atkbd_attr_softrepeat.attr,
	&atkbd_attr_softraw.attr,
	&atkbd_attr_err_count.attr,
	NULL
};

static struct attribute_group atkbd_attribute_group = {
	.attrs	= atkbd_attributes,
};

static const unsigned int xl_table[] = {
	ATKBD_RET_BAT, ATKBD_RET_ERR, ATKBD_RET_ACK,
	ATKBD_RET_NAK, ATKBD_RET_HANJA, ATKBD_RET_HANGEUL,
};

/*
 * Checks if we should mangle the scancode to extract 'release' bit
 * in translated mode.
 */
static int atkbd_need_xlate(unsigned long xl_bit, unsigned char code)
{
	int i;

	if (code == ATKBD_RET_EMUL0 || code == ATKBD_RET_EMUL1)
		return 0;

	for (i = 0; i < ARRAY_SIZE(xl_table); i++)
		if (code == xl_table[i])
			return test_bit(i, &xl_bit);

	return 1;
}

/*
 * Calculates new value of xl_bit so the driver can distinguish
 * between make/break pair of scancodes for select keys and PS/2
 * protocol responses.
 */
static void atkbd_calculate_xl_bit(struct atkbd *atkbd, unsigned char code)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(xl_table); i++) {
		if (!((code ^ xl_table[i]) & 0x7f)) {
			if (code & 0x80)
				__clear_bit(i, &atkbd->xl_bit);
			else
				__set_bit(i, &atkbd->xl_bit);
			break;
		}
	}
}

/*
 * Encode the scancode, 0xe0 prefix, and high bit into a single integer,
 * keeping kernel 2.4 compatibility for set 2
 */
static unsigned int atkbd_compat_scancode(struct atkbd *atkbd, unsigned int code)
{
	if (atkbd->set == 3) {
		if (atkbd->emul == 1)
			code |= 0x100;
        } else {
		code = (code & 0x7f) | ((code & 0x80) << 1);
		if (atkbd->emul == 1)
			code |= 0x80;
	}

	return code;
}

/*
 * atkbd_interrupt(). Here takes place processing of data received from
 * the keyboard into events.
 */

static irqreturn_t atkbd_interrupt(struct serio *serio, unsigned char data,
			unsigned int flags)
{
	struct atkbd *atkbd = serio_get_drvdata(serio);
	struct input_dev *dev = atkbd->dev;
	unsigned int code = data;
	int scroll = 0, hscroll = 0, click = -1, add_release_event = 0;
	int value;
	unsigned char keycode;

#ifdef ATKBD_DEBUG
	printk(KERN_DEBUG "atkbd.c: Received %02x flags %02x\n", data, flags);
#endif

#if !defined(__i386__) && !defined (__x86_64__)
	if ((flags & (SERIO_FRAME | SERIO_PARITY)) && (~flags & SERIO_TIMEOUT) && !atkbd->resend && atkbd->write) {
		printk(KERN_WARNING "atkbd.c: frame/parity error: %02x\n", flags);
		serio_write(serio, ATKBD_CMD_RESEND);
		atkbd->resend = 1;
		goto out;
	}

	if (!flags && data == ATKBD_RET_ACK)
		atkbd->resend = 0;
#endif

	if (unlikely(atkbd->ps2dev.flags & PS2_FLAG_ACK))
		if  (ps2_handle_ack(&atkbd->ps2dev, data))
			goto out;

	if (unlikely(atkbd->ps2dev.flags & PS2_FLAG_CMD))
		if  (ps2_handle_response(&atkbd->ps2dev, data))
			goto out;

	if (!atkbd->enabled)
		goto out;

	input_event(dev, EV_MSC, MSC_RAW, code);

	if (atkbd->translated) {

		if (atkbd->emul || atkbd_need_xlate(atkbd->xl_bit, code)) {
			atkbd->release = code >> 7;
			code &= 0x7f;
		}

		if (!atkbd->emul)
			atkbd_calculate_xl_bit(atkbd, data);
	}

	switch (code) {
		case ATKBD_RET_BAT:
			atkbd->enabled = 0;
			serio_reconnect(atkbd->ps2dev.serio);
			goto out;
		case ATKBD_RET_EMUL0:
			atkbd->emul = 1;
			goto out;
		case ATKBD_RET_EMUL1:
			atkbd->emul = 2;
			goto out;
		case ATKBD_RET_RELEASE:
			atkbd->release = 1;
			goto out;
		case ATKBD_RET_ACK:
		case ATKBD_RET_NAK:
			if (printk_ratelimit())
				printk(KERN_WARNING "atkbd.c: Spurious %s on %s. "
				       "Some program might be trying access hardware directly.\n",
				       data == ATKBD_RET_ACK ? "ACK" : "NAK", serio->phys);
			goto out;
		case ATKBD_RET_HANGEUL:
		case ATKBD_RET_HANJA:
			/*
			 * These keys do not report release and thus need to be
			 * flagged properly
			 */
			add_release_event = 1;
			break;
		case ATKBD_RET_ERR:
			atkbd->err_count++;
#ifdef ATKBD_DEBUG
			printk(KERN_DEBUG "atkbd.c: Keyboard on %s reports too many keys pressed.\n", serio->phys);
#endif
			goto out;
	}

	code = atkbd_compat_scancode(atkbd, code);

	if (atkbd->emul && --atkbd->emul)
		goto out;

	keycode = atkbd->keycode[code];

	if (keycode != ATKBD_KEY_NULL)
		input_event(dev, EV_MSC, MSC_SCAN, code);

	switch (keycode) {
		case ATKBD_KEY_NULL:
			break;
		case ATKBD_KEY_UNKNOWN:
			printk(KERN_WARNING
			       "atkbd.c: Unknown key %s (%s set %d, code %#x on %s).\n",
			       atkbd->release ? "released" : "pressed",
			       atkbd->translated ? "translated" : "raw",
			       atkbd->set, code, serio->phys);
			printk(KERN_WARNING
			       "atkbd.c: Use 'setkeycodes %s%02x <keycode>' to make it known.\n",
			       code & 0x80 ? "e0" : "", code & 0x7f);
			input_sync(dev);
			break;
		case ATKBD_SCR_1:
			scroll = 1 - atkbd->release * 2;
			break;
		case ATKBD_SCR_2:
			scroll = 2 - atkbd->release * 4;
			break;
		case ATKBD_SCR_4:
			scroll = 4 - atkbd->release * 8;
			break;
		case ATKBD_SCR_8:
			scroll = 8 - atkbd->release * 16;
			break;
		case ATKBD_SCR_CLICK:
			click = !atkbd->release;
			break;
		case ATKBD_SCR_LEFT:
			hscroll = -1;
			break;
		case ATKBD_SCR_RIGHT:
			hscroll = 1;
			break;
		default:
			if (atkbd->release) {
				value = 0;
				atkbd->last = 0;
			} else if (!atkbd->softrepeat && test_bit(keycode, dev->key)) {
				/* Workaround Toshiba laptop multiple keypress */
				value = time_before(jiffies, atkbd->time) && atkbd->last == code ? 1 : 2;
			} else {
				value = 1;
				atkbd->last = code;
				atkbd->time = jiffies + msecs_to_jiffies(dev->rep[REP_DELAY]) / 2;
			}

			input_event(dev, EV_KEY, keycode, value);
			input_sync(dev);

			if (value && add_release_event) {
				input_report_key(dev, keycode, 0);
				input_sync(dev);
			}
	}

	if (atkbd->scroll) {
		if (click != -1)
			input_report_key(dev, BTN_MIDDLE, click);
		input_report_rel(dev, REL_WHEEL, scroll);
		input_report_rel(dev, REL_HWHEEL, hscroll);
		input_sync(dev);
	}

	atkbd->release = 0;
out:
	return IRQ_HANDLED;
}

static int atkbd_set_repeat_rate(struct atkbd *atkbd)
{
	const short period[32] =
		{ 33,  37,  42,  46,  50,  54,  58,  63,  67,  75,  83,  92, 100, 109, 116, 125,
		 133, 149, 167, 182, 200, 217, 232, 250, 270, 303, 333, 370, 400, 435, 470, 500 };
	const short delay[4] =
		{ 250, 500, 750, 1000 };

	struct input_dev *dev = atkbd->dev;
	unsigned char param;
	int i = 0, j = 0;

	while (i < ARRAY_SIZE(period) - 1 && period[i] < dev->rep[REP_PERIOD])
		i++;
	dev->rep[REP_PERIOD] = period[i];

	while (j < ARRAY_SIZE(delay) - 1 && delay[j] < dev->rep[REP_DELAY])
		j++;
	dev->rep[REP_DELAY] = delay[j];

	param = i | (j << 5);
	return ps2_command(&atkbd->ps2dev, &param, ATKBD_CMD_SETREP);
}

static int atkbd_set_leds(struct atkbd *atkbd)
{
	struct input_dev *dev = atkbd->dev;
	unsigned char param[2];

	param[0] = (test_bit(LED_SCROLLL, dev->led) ? 1 : 0)
		 | (test_bit(LED_NUML,    dev->led) ? 2 : 0)
		 | (test_bit(LED_CAPSL,   dev->led) ? 4 : 0);
	if (ps2_command(&atkbd->ps2dev, param, ATKBD_CMD_SETLEDS))
		return -1;

	if (atkbd->extra) {
		param[0] = 0;
		param[1] = (test_bit(LED_COMPOSE, dev->led) ? 0x01 : 0)
			 | (test_bit(LED_SLEEP,   dev->led) ? 0x02 : 0)
			 | (test_bit(LED_SUSPEND, dev->led) ? 0x04 : 0)
			 | (test_bit(LED_MISC,    dev->led) ? 0x10 : 0)
			 | (test_bit(LED_MUTE,    dev->led) ? 0x20 : 0);
		if (ps2_command(&atkbd->ps2dev, param, ATKBD_CMD_EX_SETLEDS))
			return -1;
	}

	return 0;
}

/*
 * atkbd_event_work() is used to complete processing of events that
 * can not be processed by input_event() which is often called from
 * interrupt context.
 */

static void atkbd_event_work(struct work_struct *work)
{
	struct atkbd *atkbd = container_of(work, struct atkbd, event_work.work);

	mutex_lock(&atkbd->event_mutex);

	if (test_and_clear_bit(ATKBD_LED_EVENT_BIT, &atkbd->event_mask))
		atkbd_set_leds(atkbd);

	if (test_and_clear_bit(ATKBD_REP_EVENT_BIT, &atkbd->event_mask))
		atkbd_set_repeat_rate(atkbd);

	mutex_unlock(&atkbd->event_mutex);
}

/*
 * Schedule switch for execution. We need to throttle requests,
 * otherwise keyboard may become unresponsive.
 */
static void atkbd_schedule_event_work(struct atkbd *atkbd, int event_bit)
{
	unsigned long delay = msecs_to_jiffies(50);

	if (time_after(jiffies, atkbd->event_jiffies + delay))
		delay = 0;

	atkbd->event_jiffies = jiffies;
	set_bit(event_bit, &atkbd->event_mask);
	wmb();
	schedule_delayed_work(&atkbd->event_work, delay);
}

/*
 * Event callback from the input module. Events that change the state of
 * the hardware are processed here. If action can not be performed in
 * interrupt context it is offloaded to atkbd_event_work.
 */

static int atkbd_event(struct input_dev *dev,
			unsigned int type, unsigned int code, int value)
{
	struct atkbd *atkbd = input_get_drvdata(dev);

	if (!atkbd->write)
		return -1;

	switch (type) {

		case EV_LED:
			atkbd_schedule_event_work(atkbd, ATKBD_LED_EVENT_BIT);
			return 0;

		case EV_REP:
			if (!atkbd->softrepeat)
				atkbd_schedule_event_work(atkbd, ATKBD_REP_EVENT_BIT);
			return 0;
	}

	return -1;
}

/*
 * atkbd_enable() signals that interrupt handler is allowed to
 * generate input events.
 */

static inline void atkbd_enable(struct atkbd *atkbd)
{
	serio_pause_rx(atkbd->ps2dev.serio);
	atkbd->enabled = 1;
	serio_continue_rx(atkbd->ps2dev.serio);
}

/*
 * atkbd_disable() tells input handler that all incoming data except
 * for ACKs and command response should be dropped.
 */

static inline void atkbd_disable(struct atkbd *atkbd)
{
	serio_pause_rx(atkbd->ps2dev.serio);
	atkbd->enabled = 0;
	serio_continue_rx(atkbd->ps2dev.serio);
}

/*
 * atkbd_probe() probes for an AT keyboard on a serio port.
 */

static int atkbd_probe(struct atkbd *atkbd)
{
	struct ps2dev *ps2dev = &atkbd->ps2dev;
	unsigned char param[2];

/*
 * Some systems, where the bit-twiddling when testing the io-lines of the
 * controller may confuse the keyboard need a full reset of the keyboard. On
 * these systems the BIOS also usually doesn't do it for us.
 */

	if (atkbd_reset)
		if (ps2_command(ps2dev, NULL, ATKBD_CMD_RESET_BAT))
			printk(KERN_WARNING "atkbd.c: keyboard reset failed on %s\n", ps2dev->serio->phys);

/*
 * Then we check the keyboard ID. We should get 0xab83 under normal conditions.
 * Some keyboards report different values, but the first byte is always 0xab or
 * 0xac. Some old AT keyboards don't report anything. If a mouse is connected, this
 * should make sure we don't try to set the LEDs on it.
 */

	param[0] = param[1] = 0xa5;	/* initialize with invalid values */
	if (ps2_command(ps2dev, param, ATKBD_CMD_GETID)) {

/*
 * If the get ID command failed, we check if we can at least set the LEDs on
 * the keyboard. This should work on every keyboard out there. It also turns
 * the LEDs off, which we want anyway.
 */
		param[0] = 0;
		if (ps2_command(ps2dev, param, ATKBD_CMD_SETLEDS))
			return -1;
		atkbd->id = 0xabba;
		return 0;
	}

	if (!ps2_is_keyboard_id(param[0]))
		return -1;

	atkbd->id = (param[0] << 8) | param[1];

	if (atkbd->id == 0xaca1 && atkbd->translated) {
		printk(KERN_ERR "atkbd.c: NCD terminal keyboards are only supported on non-translating\n");
		printk(KERN_ERR "atkbd.c: controllers. Use i8042.direct=1 to disable translation.\n");
		return -1;
	}

	return 0;
}

/*
 * atkbd_select_set checks if a keyboard has a working Set 3 support, and
 * sets it into that. Unfortunately there are keyboards that can be switched
 * to Set 3, but don't work well in that (BTC Multimedia ...)
 */

static int atkbd_select_set(struct atkbd *atkbd, int target_set, int allow_extra)
{
	struct ps2dev *ps2dev = &atkbd->ps2dev;
	unsigned char param[2];

	atkbd->extra = 0;
/*
 * For known special keyboards we can go ahead and set the correct set.
 * We check for NCD PS/2 Sun, NorthGate OmniKey 101 and
 * IBM RapidAccess / IBM EzButton / Chicony KBP-8993 keyboards.
 */

	if (atkbd->translated)
		return 2;

	if (atkbd->id == 0xaca1) {
		param[0] = 3;
		ps2_command(ps2dev, param, ATKBD_CMD_SSCANSET);
		return 3;
	}

	if (allow_extra) {
		param[0] = 0x71;
		if (!ps2_command(ps2dev, param, ATKBD_CMD_EX_ENABLE)) {
			atkbd->extra = 1;
			return 2;
		}
	}

	if (target_set != 3)
		return 2;

	if (!ps2_command(ps2dev, param, ATKBD_CMD_OK_GETID)) {
		atkbd->id = param[0] << 8 | param[1];
		return 2;
	}

	param[0] = 3;
	if (ps2_command(ps2dev, param, ATKBD_CMD_SSCANSET))
		return 2;

	param[0] = 0;
	if (ps2_command(ps2dev, param, ATKBD_CMD_GSCANSET))
		return 2;

	if (param[0] != 3) {
		param[0] = 2;
		if (ps2_command(ps2dev, param, ATKBD_CMD_SSCANSET))
		return 2;
	}

	ps2_command(ps2dev, param, ATKBD_CMD_SETALL_MBR);

	return 3;
}

static int atkbd_activate(struct atkbd *atkbd)
{
	struct ps2dev *ps2dev = &atkbd->ps2dev;
	unsigned char param[1];

/*
 * Set the LEDs to a defined state.
 */

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

/*
 * Set autorepeat to fastest possible.
 */

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

/*
 * Enable the keyboard to receive keystrokes.
 */

	if (ps2_command(ps2dev, NULL, ATKBD_CMD_ENABLE)) {
		printk(KERN_ERR "atkbd.c: Failed to enable keyboard on %s\n",
			ps2dev->serio->phys);
		return -1;
	}

	return 0;
}

/*
 * atkbd_cleanup() restores the keyboard state so that BIOS is happy after a
 * reboot.
 */

static void atkbd_cleanup(struct serio *serio)
{
	struct atkbd *atkbd = serio_get_drvdata(serio);
	ps2_command(&atkbd->ps2dev, NULL, ATKBD_CMD_RESET_BAT);
}


/*
 * atkbd_disconnect() closes and frees.
 */

static void atkbd_disconnect(struct serio *serio)
{
	struct atkbd *atkbd = serio_get_drvdata(serio);

	atkbd_disable(atkbd);

	/* make sure we don't have a command in flight */
	synchronize_sched();  /* Allow atkbd_interrupt()s to complete. */
	flush_scheduled_work();

	sysfs_remove_group(&serio->dev.kobj, &atkbd_attribute_group);
	input_unregister_device(atkbd->dev);
	serio_close(serio);
	serio_set_drvdata(serio, NULL);
	kfree(atkbd);
}


/*
 * atkbd_set_keycode_table() initializes keyboard's keycode table
 * according to the selected scancode set
 */

static void atkbd_set_keycode_table(struct atkbd *atkbd)
{
	int i, j;

	memset(atkbd->keycode, 0, sizeof(atkbd->keycode));

	if (atkbd->translated) {
		for (i = 0; i < 128; i++) {
			atkbd->keycode[i] = atkbd_set2_keycode[atkbd_unxlate_table[i]];
			atkbd->keycode[i | 0x80] = atkbd_set2_keycode[atkbd_unxlate_table[i] | 0x80];
			if (atkbd->scroll)
				for (j = 0; j < ARRAY_SIZE(atkbd_scroll_keys); j++)
					if ((atkbd_unxlate_table[i] | 0x80) == atkbd_scroll_keys[j].set2)
						atkbd->keycode[i | 0x80] = atkbd_scroll_keys[j].keycode;
		}
	} else if (atkbd->set == 3) {
		memcpy(atkbd->keycode, atkbd_set3_keycode, sizeof(atkbd->keycode));
	} else {
		memcpy(atkbd->keycode, atkbd_set2_keycode, sizeof(atkbd->keycode));

		if (atkbd->scroll)
			for (i = 0; i < ARRAY_SIZE(atkbd_scroll_keys); i++)
				atkbd->keycode[atkbd_scroll_keys[i].set2] = atkbd_scroll_keys[i].keycode;
	}

	atkbd->keycode[atkbd_compat_scancode(atkbd, ATKBD_RET_HANGEUL)] = KEY_HANGUEL;
	atkbd->keycode[atkbd_compat_scancode(atkbd, ATKBD_RET_HANJA)] = KEY_HANJA;
}

/*
 * atkbd_set_device_attrs() sets up keyboard's input device structure
 */

static void atkbd_set_device_attrs(struct atkbd *atkbd)
{
	struct input_dev *input_dev = atkbd->dev;
	int i;

	if (atkbd->extra)
		snprintf(atkbd->name, sizeof(atkbd->name),
			 "AT Set 2 Extra keyboard");
	else
		snprintf(atkbd->name, sizeof(atkbd->name),
			 "AT %s Set %d keyboard",
			 atkbd->translated ? "Translated" : "Raw", atkbd->set);

	snprintf(atkbd->phys, sizeof(atkbd->phys),
		 "%s/input0", atkbd->ps2dev.serio->phys);

	input_dev->name = atkbd->name;
	input_dev->phys = atkbd->phys;
	input_dev->id.bustype = BUS_I8042;
	input_dev->id.vendor = 0x0001;
	input_dev->id.product = atkbd->translated ? 1 : atkbd->set;
	input_dev->id.version = atkbd->id;
	input_dev->event = atkbd_event;
	input_dev->dev.parent = &atkbd->ps2dev.serio->dev;

	input_set_drvdata(input_dev, atkbd);

	input_dev->evbit[0] = BIT(EV_KEY) | BIT(EV_REP) | BIT(EV_MSC);

	if (atkbd->write) {
		input_dev->evbit[0] |= BIT(EV_LED);
		input_dev->ledbit[0] = BIT(LED_NUML) | BIT(LED_CAPSL) | BIT(LED_SCROLLL);
	}

	if (atkbd->extra)
		input_dev->ledbit[0] |= BIT(LED_COMPOSE) | BIT(LED_SUSPEND) |
					BIT(LED_SLEEP) | BIT(LED_MUTE) | BIT(LED_MISC);

	if (!atkbd->softrepeat) {
		input_dev->rep[REP_DELAY] = 250;
		input_dev->rep[REP_PERIOD] = 33;
	}

	input_dev->mscbit[0] = atkbd->softraw ? BIT(MSC_SCAN) : BIT(MSC_RAW) | BIT(MSC_SCAN);

	if (atkbd->scroll) {
		input_dev->evbit[0] |= BIT(EV_REL);
		input_dev->relbit[0] = BIT(REL_WHEEL) | BIT(REL_HWHEEL);
		set_bit(BTN_MIDDLE, input_dev->keybit);
	}

	input_dev->keycode = atkbd->keycode;
	input_dev->keycodesize = sizeof(unsigned char);
	input_dev->keycodemax = ARRAY_SIZE(atkbd_set2_keycode);

	for (i = 0; i < 512; i++)
		if (atkbd->keycode[i] && atkbd->keycode[i] < ATKBD_SPECIAL)
			set_bit(atkbd->keycode[i], input_dev->keybit);
}

/*
 * atkbd_connect() is called when the serio module finds an interface
 * that isn't handled yet by an appropriate device driver. We check if
 * there is an AT keyboard out there and if yes, we register ourselves
 * to the input module.
 */

static int atkbd_connect(struct serio *serio, struct serio_driver *drv)
{
	struct atkbd *atkbd;
	struct input_dev *dev;
	int err = -ENOMEM;

	atkbd = kzalloc(sizeof(struct atkbd), GFP_KERNEL);
	dev = input_allocate_device();
	if (!atkbd || !dev)
		goto fail1;

	atkbd->dev = dev;
	ps2_init(&atkbd->ps2dev, serio);
	INIT_DELAYED_WORK(&atkbd->event_work, atkbd_event_work);
	mutex_init(&atkbd->event_mutex);

	switch (serio->id.type) {

		case SERIO_8042_XL:
			atkbd->translated = 1;
		case SERIO_8042:
			if (serio->write)
				atkbd->write = 1;
			break;
	}

	atkbd->softraw = atkbd_softraw;
	atkbd->softrepeat = atkbd_softrepeat;
	atkbd->scroll = atkbd_scroll;

	if (atkbd->softrepeat)
		atkbd->softraw = 1;

	serio_set_drvdata(serio, atkbd);

	err = serio_open(serio, drv);
	if (err)
		goto fail2;

	if (atkbd->write) {

		if (atkbd_probe(atkbd)) {
			err = -ENODEV;
			goto fail3;
		}

		atkbd->set = atkbd_select_set(atkbd, atkbd_set, atkbd_extra);
		atkbd_activate(atkbd);

	} else {
		atkbd->set = 2;
		atkbd->id = 0xab00;
	}

	atkbd_set_keycode_table(atkbd);
	atkbd_set_device_attrs(atkbd);

	err = sysfs_create_group(&serio->dev.kobj, &atkbd_attribute_group);
	if (err)
		goto fail3;

	atkbd_enable(atkbd);

	err = input_register_device(atkbd->dev);
	if (err)
		goto fail4;

	return 0;

 fail4: sysfs_remove_group(&serio->dev.kobj, &atkbd_attribute_group);
 fail3:	serio_close(serio);
 fail2:	serio_set_drvdata(serio, NULL);
 fail1:	input_free_device(dev);
	kfree(atkbd);
	return err;
}

/*
 * atkbd_reconnect() tries to restore keyboard into a sane state and is
 * most likely called on resume.
 */

static int atkbd_reconnect(struct serio *serio)
{
	struct atkbd *atkbd = serio_get_drvdata(serio);
	struct serio_driver *drv = serio->drv;

	if (!atkbd || !drv) {
		printk(KERN_DEBUG "atkbd: reconnect request, but serio is disconnected, ignoring...\n");
		return -1;
	}

	atkbd_disable(atkbd);

	if (atkbd->write) {
		if (atkbd_probe(atkbd))
			return -1;
		if (atkbd->set != atkbd_select_set(atkbd, atkbd->set, atkbd->extra))
			return -1;

		atkbd_activate(atkbd);

/*
 * Restore repeat rate and LEDs (that were reset by atkbd_activate)
 * to pre-resume state
 */
		if (!atkbd->softrepeat)
			atkbd_set_repeat_rate(atkbd);
		atkbd_set_leds(atkbd);
	}

	atkbd_enable(atkbd);

	return 0;
}

static struct serio_device_id atkbd_serio_ids[] = {
	{
		.type	= SERIO_8042,
		.proto	= SERIO_ANY,
		.id	= SERIO_ANY,
		.extra	= SERIO_ANY,
	},
	{
		.type	= SERIO_8042_XL,
		.proto	= SERIO_ANY,
		.id	= SERIO_ANY,
		.extra	= SERIO_ANY,
	},
	{
		.type	= SERIO_RS232,
		.proto	= SERIO_PS2SER,
		.id	= SERIO_ANY,
		.extra	= SERIO_ANY,
	},
	{ 0 }
};

MODULE_DEVICE_TABLE(serio, atkbd_serio_ids);

static struct serio_driver atkbd_drv = {
	.driver		= {
		.name	= "atkbd",
	},
	.description	= DRIVER_DESC,
	.id_table	= atkbd_serio_ids,
	.interrupt	= atkbd_interrupt,
	.connect	= atkbd_connect,
	.reconnect	= atkbd_reconnect,
	.disconnect	= atkbd_disconnect,
	.cleanup	= atkbd_cleanup,
};

static ssize_t atkbd_attr_show_helper(struct device *dev, char *buf,
				ssize_t (*handler)(struct atkbd *, char *))
{
	struct serio *serio = to_serio_port(dev);
	int retval;

	retval = serio_pin_driver(serio);
	if (retval)
		return retval;

	if (serio->drv != &atkbd_drv) {
		retval = -ENODEV;
		goto out;
	}

	retval = handler((struct atkbd *)serio_get_drvdata(serio), buf);

out:
	serio_unpin_driver(serio);
	return retval;
}

static ssize_t atkbd_attr_set_helper(struct device *dev, const char *buf, size_t count,
				ssize_t (*handler)(struct atkbd *, const char *, size_t))
{
	struct serio *serio = to_serio_port(dev);
	struct atkbd *atkbd;
	int retval;

	retval = serio_pin_driver(serio);
	if (retval)
		return retval;

	if (serio->drv != &atkbd_drv) {
		retval = -ENODEV;
		goto out;
	}

	atkbd = serio_get_drvdata(serio);
	atkbd_disable(atkbd);
	retval = handler(atkbd, buf, count);
	atkbd_enable(atkbd);

out:
	serio_unpin_driver(serio);
	return retval;
}

static ssize_t atkbd_show_extra(struct atkbd *atkbd, char *buf)
{
	return sprintf(buf, "%d\n", atkbd->extra ? 1 : 0);
}

static ssize_t atkbd_set_extra(struct atkbd *atkbd, const char *buf, size_t count)
{
	struct input_dev *old_dev, *new_dev;
	unsigned long value;
	char *rest;
	int err;
	unsigned char old_extra, old_set;

	if (!atkbd->write)
		return -EIO;

	value = simple_strtoul(buf, &rest, 10);
	if (*rest || value > 1)
		return -EINVAL;

	if (atkbd->extra != value) {
		/*
		 * Since device's properties will change we need to
		 * unregister old device. But allocate and register
		 * new one first to make sure we have it.
		 */
		old_dev = atkbd->dev;
		old_extra = atkbd->extra;
		old_set = atkbd->set;

		new_dev = input_allocate_device();
		if (!new_dev)
			return -ENOMEM;

		atkbd->dev = new_dev;
		atkbd->set = atkbd_select_set(atkbd, atkbd->set, value);
		atkbd_activate(atkbd);
		atkbd_set_keycode_table(atkbd);
		atkbd_set_device_attrs(atkbd);

		err = input_register_device(atkbd->dev);
		if (err) {
			input_free_device(new_dev);

			atkbd->dev = old_dev;
			atkbd->set = atkbd_select_set(atkbd, old_set, old_extra);
			atkbd_set_keycode_table(atkbd);
			atkbd_set_device_attrs(atkbd);

			return err;
		}
		input_unregister_device(old_dev);

	}
	return count;
}

static ssize_t atkbd_show_scroll(struct atkbd *atkbd, char *buf)
{
	return sprintf(buf, "%d\n", atkbd->scroll ? 1 : 0);
}

static ssize_t atkbd_set_scroll(struct atkbd *atkbd, const char *buf, size_t count)
{
	struct input_dev *old_dev, *new_dev;
	unsigned long value;
	char *rest;
	int err;
	unsigned char old_scroll;

	value = simple_strtoul(buf, &rest, 10);
	if (*rest || value > 1)
		return -EINVAL;

	if (atkbd->scroll != value) {
		old_dev = atkbd->dev;
		old_scroll = atkbd->scroll;

		new_dev = input_allocate_device();
		if (!new_dev)
			return -ENOMEM;

		atkbd->dev = new_dev;
		atkbd->scroll = value;
		atkbd_set_keycode_table(atkbd);
		atkbd_set_device_attrs(atkbd);

		err = input_register_device(atkbd->dev);
		if (err) {
			input_free_device(new_dev);

			atkbd->scroll = old_scroll;
			atkbd->dev = old_dev;
			atkbd_set_keycode_table(atkbd);
			atkbd_set_device_attrs(atkbd);

			return err;
		}
		input_unregister_device(old_dev);
	}
	return count;
}

static ssize_t atkbd_show_set(struct atkbd *atkbd, char *buf)
{
	return sprintf(buf, "%d\n", atkbd->set);
}

static ssize_t atkbd_set_set(struct atkbd *atkbd, const char *buf, size_t count)
{
	struct input_dev *old_dev, *new_dev;
	unsigned long value;
	char *rest;
	int err;
	unsigned char old_set, old_extra;

	if (!atkbd->write)
		return -EIO;

	value = simple_strtoul(buf, &rest, 10);
	if (*rest || (value != 2 && value != 3))
		return -EINVAL;

	if (atkbd->set != value) {
		old_dev = atkbd->dev;
		old_extra = atkbd->extra;
		old_set = atkbd->set;

		new_dev = input_allocate_device();
		if (!new_dev)
			return -ENOMEM;

		atkbd->dev = new_dev;
		atkbd->set = atkbd_select_set(atkbd, value, atkbd->extra);
		atkbd_activate(atkbd);
		atkbd_set_keycode_table(atkbd);
		atkbd_set_device_attrs(atkbd);

		err = input_register_device(atkbd->dev);
		if (err) {
			input_free_device(new_dev);

			atkbd->dev = old_dev;
			atkbd->set = atkbd_select_set(atkbd, old_set, old_extra);
			atkbd_set_keycode_table(atkbd);
			atkbd_set_device_attrs(atkbd);

			return err;
		}
		input_unregister_device(old_dev);
	}
	return count;
}

static ssize_t atkbd_show_softrepeat(struct atkbd *atkbd, char *buf)
{
	return sprintf(buf, "%d\n", atkbd->softrepeat ? 1 : 0);
}

static ssize_t atkbd_set_softrepeat(struct atkbd *atkbd, const char *buf, size_t count)
{
	struct input_dev *old_dev, *new_dev;
	unsigned long value;
	char *rest;
	int err;
	unsigned char old_softrepeat, old_softraw;

	if (!atkbd->write)
		return -EIO;

	value = simple_strtoul(buf, &rest, 10);
	if (*rest || value > 1)
		return -EINVAL;

	if (atkbd->softrepeat != value) {
		old_dev = atkbd->dev;
		old_softrepeat = atkbd->softrepeat;
		old_softraw = atkbd->softraw;

		new_dev = input_allocate_device();
		if (!new_dev)
			return -ENOMEM;

		atkbd->dev = new_dev;
		atkbd->softrepeat = value;
		if (atkbd->softrepeat)
			atkbd->softraw = 1;
		atkbd_set_device_attrs(atkbd);

		err = input_register_device(atkbd->dev);
		if (err) {
			input_free_device(new_dev);

			atkbd->dev = old_dev;
			atkbd->softrepeat = old_softrepeat;
			atkbd->softraw = old_softraw;
			atkbd_set_device_attrs(atkbd);

			return err;
		}
		input_unregister_device(old_dev);
	}
	return count;
}


static ssize_t atkbd_show_softraw(struct atkbd *atkbd, char *buf)
{
	return sprintf(buf, "%d\n", atkbd->softraw ? 1 : 0);
}

static ssize_t atkbd_set_softraw(struct atkbd *atkbd, const char *buf, size_t count)
{
	struct input_dev *old_dev, *new_dev;
	unsigned long value;
	char *rest;
	int err;
	unsigned char old_softraw;

	value = simple_strtoul(buf, &rest, 10);
	if (*rest || value > 1)
		return -EINVAL;

	if (atkbd->softraw != value) {
		old_dev = atkbd->dev;
		old_softraw = atkbd->softraw;

		new_dev = input_allocate_device();
		if (!new_dev)
			return -ENOMEM;

		atkbd->dev = new_dev;
		atkbd->softraw = value;
		atkbd_set_device_attrs(atkbd);

		err = input_register_device(atkbd->dev);
		if (err) {
			input_free_device(new_dev);

			atkbd->dev = old_dev;
			atkbd->softraw = old_softraw;
			atkbd_set_device_attrs(atkbd);

			return err;
		}
		input_unregister_device(old_dev);
	}
	return count;
}

static ssize_t atkbd_show_err_count(struct atkbd *atkbd, char *buf)
{
	return sprintf(buf, "%lu\n", atkbd->err_count);
}


static int __init atkbd_init(void)
{
	return serio_register_driver(&atkbd_drv);
}

static void __exit atkbd_exit(void)
{
	serio_unregister_driver(&atkbd_drv);
}

module_init(atkbd_init);
module_exit(atkbd_exit);