atkbd.c

at91_ps2_驱动~at91sam9261的IO口模拟PS2键盘驱动程序设计——最新

/*
 * 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.
 * 标准AT键盘以及PS/2接口键盘的扫描码和2，3套码.
 */

#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 <[e-mail]>");
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.
 * 下列为键盘扫描码 全部为默认值
 */

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 work_struct event_work;
	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
 * 译码扫描码，在...前面加上0xe0，高位对应着单独的整数
 * 与2.4内核保存兼容性
 */
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.
 * AT键盘中断，这里发生键盘输入事件的数据处理
 */

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:
			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;