keyboard.c

来自「linux 内核源代码」· C语言 代码 · 共 1,426 行 · 第 1/3 页

/*
 * linux/drivers/char/keyboard.c
 *
 * Written for linux by Johan Myreen as a translation from
 * the assembly version by Linus (with diacriticals added)
 *
 * Some additional features added by Christoph Niemann (ChN), March 1993
 *
 * Loadable keymaps by Risto Kankkunen, May 1993
 *
 * Diacriticals redone & other small changes, [e-mail], June 1993
 * Added decr/incr_console, dynamic keymaps, Unicode support,
 * dynamic function/string keys, led setting,  Sept 1994
 * `Sticky' modifier keys, 951006.
 *
 * 11-11-96: SAK should now work in the raw mode (Martin Mares)
 *
 * Modified to provide 'generic' keyboard support by Hamish Macdonald
 * Merge with the m68k keyboard driver and split-off of the PC low-level
 * parts by Geert Uytterhoeven, May 1997
 *
 * 27-05-97: Added support for the Magic SysRq Key (Martin Mares)
 * 30-07-98: Dead keys redone, [e-mail].
 * 21-08-02: Converted to input API, major cleanup. (Vojtech Pavlik)
 */

#include <linux/consolemap.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/irq.h>

#include <linux/kbd_kern.h>
#include <linux/kbd_diacr.h>
#include <linux/vt_kern.h>
#include <linux/consolemap.h>
#include <linux/sysrq.h>
#include <linux/input.h>
#include <linux/reboot.h>
#include <linux/notifier.h>

extern void ctrl_alt_del(void);

/*
 * Exported functions/variables
 */

#define KBD_DEFMODE ((1 << VC_REPEAT) | (1 << VC_META))

/*
 * Some laptops take the 789uiojklm,. keys as number pad when NumLock is on.
 * This seems a good reason to start with NumLock off. On HIL keyboards
 * of PARISC machines however there is no NumLock key and everyone expects the keypad
 * to be used for numbers.
 */

#if defined(CONFIG_PARISC) && (defined(CONFIG_KEYBOARD_HIL) || defined(CONFIG_KEYBOARD_HIL_OLD))
#define KBD_DEFLEDS (1 << VC_NUMLOCK)
#else
#define KBD_DEFLEDS 0
#endif

#define KBD_DEFLOCK 0

void compute_shiftstate(void);

/*
 * Handler Tables.
 */

#define K_HANDLERS\
	k_self,		k_fn,		k_spec,		k_pad,\
	k_dead,		k_cons,		k_cur,		k_shift,\
	k_meta,		k_ascii,	k_lock,		k_lowercase,\
	k_slock,	k_dead2,	k_brl,		k_ignore

typedef void (k_handler_fn)(struct vc_data *vc, unsigned char value,
			    char up_flag);
static k_handler_fn K_HANDLERS;
k_handler_fn *k_handler[16] = { K_HANDLERS };
EXPORT_SYMBOL_GPL(k_handler);

#define FN_HANDLERS\
	fn_null,	fn_enter,	fn_show_ptregs,	fn_show_mem,\
	fn_show_state,	fn_send_intr,	fn_lastcons,	fn_caps_toggle,\
	fn_num,		fn_hold,	fn_scroll_forw,	fn_scroll_back,\
	fn_boot_it,	fn_caps_on,	fn_compose,	fn_SAK,\
	fn_dec_console, fn_inc_console, fn_spawn_con,	fn_bare_num

typedef void (fn_handler_fn)(struct vc_data *vc);
static fn_handler_fn FN_HANDLERS;
static fn_handler_fn *fn_handler[] = { FN_HANDLERS };

/*
 * Variables exported for vt_ioctl.c
 */

/* maximum values each key_handler can handle */
const int max_vals[] = {
	255, ARRAY_SIZE(func_table) - 1, ARRAY_SIZE(fn_handler) - 1, NR_PAD - 1,
	NR_DEAD - 1, 255, 3, NR_SHIFT - 1, 255, NR_ASCII - 1, NR_LOCK - 1,
	255, NR_LOCK - 1, 255, NR_BRL - 1
};

const int NR_TYPES = ARRAY_SIZE(max_vals);

struct kbd_struct kbd_table[MAX_NR_CONSOLES];
static struct kbd_struct *kbd = kbd_table;

struct vt_spawn_console vt_spawn_con = {
	.lock = __SPIN_LOCK_UNLOCKED(vt_spawn_con.lock),
	.pid  = NULL,
	.sig  = 0,
};

/*
 * Variables exported for vt.c
 */

int shift_state = 0;

/*
 * Internal Data.
 */

static struct input_handler kbd_handler;
static unsigned long key_down[BITS_TO_LONGS(KEY_CNT)];	/* keyboard key bitmap */
static unsigned char shift_down[NR_SHIFT];		/* shift state counters.. */
static int dead_key_next;
static int npadch = -1;					/* -1 or number assembled on pad */
static unsigned int diacr;
static char rep;					/* flag telling character repeat */

static unsigned char ledstate = 0xff;			/* undefined */
static unsigned char ledioctl;

static struct ledptr {
	unsigned int *addr;
	unsigned int mask;
	unsigned char valid:1;
} ledptrs[3];

/* Simple translation table for the SysRq keys */

#ifdef CONFIG_MAGIC_SYSRQ
unsigned char kbd_sysrq_xlate[KEY_MAX + 1] =
        "\000\0331234567890-=\177\t"                    /* 0x00 - 0x0f */
        "qwertyuiop[]\r\000as"                          /* 0x10 - 0x1f */
        "dfghjkl;'`\000\\zxcv"                          /* 0x20 - 0x2f */
        "bnm,./\000*\000 \000\201\202\203\204\205"      /* 0x30 - 0x3f */
        "\206\207\210\211\212\000\000789-456+1"         /* 0x40 - 0x4f */
        "230\177\000\000\213\214\000\000\000\000\000\000\000\000\000\000" /* 0x50 - 0x5f */
        "\r\000/";                                      /* 0x60 - 0x6f */
static int sysrq_down;
static int sysrq_alt_use;
#endif
static int sysrq_alt;

/*
 * Notifier list for console keyboard events
 */
static ATOMIC_NOTIFIER_HEAD(keyboard_notifier_list);

int register_keyboard_notifier(struct notifier_block *nb)
{
	return atomic_notifier_chain_register(&keyboard_notifier_list, nb);
}
EXPORT_SYMBOL_GPL(register_keyboard_notifier);

int unregister_keyboard_notifier(struct notifier_block *nb)
{
	return atomic_notifier_chain_unregister(&keyboard_notifier_list, nb);
}
EXPORT_SYMBOL_GPL(unregister_keyboard_notifier);

/*
 * Translation of scancodes to keycodes. We set them on only the first
 * keyboard in the list that accepts the scancode and keycode.
 * Explanation for not choosing the first attached keyboard anymore:
 *  USB keyboards for example have two event devices: one for all "normal"
 *  keys and one for extra function keys (like "volume up", "make coffee",
 *  etc.). So this means that scancodes for the extra function keys won't
 *  be valid for the first event device, but will be for the second.
 */
int getkeycode(unsigned int scancode)
{
	struct input_handle *handle;
	int keycode;
	int error = -ENODEV;

	list_for_each_entry(handle, &kbd_handler.h_list, h_node) {
		error = handle->dev->getkeycode(handle->dev, scancode, &keycode);
		if (!error)
			return keycode;
	}

	return error;
}

int setkeycode(unsigned int scancode, unsigned int keycode)
{
	struct input_handle *handle;
	int error = -ENODEV;

	list_for_each_entry(handle, &kbd_handler.h_list, h_node) {
		error = handle->dev->setkeycode(handle->dev, scancode, keycode);
		if (!error)
			break;
	}

	return error;
}

/*
 * Making beeps and bells.
 */
static void kd_nosound(unsigned long ignored)
{
	struct input_handle *handle;

	list_for_each_entry(handle, &kbd_handler.h_list, h_node) {
		if (test_bit(EV_SND, handle->dev->evbit)) {
			if (test_bit(SND_TONE, handle->dev->sndbit))
				input_inject_event(handle, EV_SND, SND_TONE, 0);
			if (test_bit(SND_BELL, handle->dev->sndbit))
				input_inject_event(handle, EV_SND, SND_BELL, 0);
		}
	}
}

static DEFINE_TIMER(kd_mksound_timer, kd_nosound, 0, 0);

void kd_mksound(unsigned int hz, unsigned int ticks)
{
	struct list_head *node;

	del_timer(&kd_mksound_timer);

	if (hz) {
		list_for_each_prev(node, &kbd_handler.h_list) {
			struct input_handle *handle = to_handle_h(node);
			if (test_bit(EV_SND, handle->dev->evbit)) {
				if (test_bit(SND_TONE, handle->dev->sndbit)) {
					input_inject_event(handle, EV_SND, SND_TONE, hz);
					break;
				}
				if (test_bit(SND_BELL, handle->dev->sndbit)) {
					input_inject_event(handle, EV_SND, SND_BELL, 1);
					break;
				}
			}
		}
		if (ticks)
			mod_timer(&kd_mksound_timer, jiffies + ticks);
	} else
		kd_nosound(0);
}

/*
 * Setting the keyboard rate.
 */

int kbd_rate(struct kbd_repeat *rep)
{
	struct list_head *node;
	unsigned int d = 0;
	unsigned int p = 0;

	list_for_each(node, &kbd_handler.h_list) {
		struct input_handle *handle = to_handle_h(node);
		struct input_dev *dev = handle->dev;

		if (test_bit(EV_REP, dev->evbit)) {
			if (rep->delay > 0)
				input_inject_event(handle, EV_REP, REP_DELAY, rep->delay);
			if (rep->period > 0)
				input_inject_event(handle, EV_REP, REP_PERIOD, rep->period);
			d = dev->rep[REP_DELAY];
			p = dev->rep[REP_PERIOD];
		}
	}
	rep->delay  = d;
	rep->period = p;
	return 0;
}

/*
 * Helper Functions.
 */
static void put_queue(struct vc_data *vc, int ch)
{
	struct tty_struct *tty = vc->vc_tty;

	if (tty) {
		tty_insert_flip_char(tty, ch, 0);
		con_schedule_flip(tty);
	}
}

static void puts_queue(struct vc_data *vc, char *cp)
{
	struct tty_struct *tty = vc->vc_tty;

	if (!tty)
		return;

	while (*cp) {
		tty_insert_flip_char(tty, *cp, 0);
		cp++;
	}
	con_schedule_flip(tty);
}

static void applkey(struct vc_data *vc, int key, char mode)
{
	static char buf[] = { 0x1b, 'O', 0x00, 0x00 };

	buf[1] = (mode ? 'O' : '[');
	buf[2] = key;
	puts_queue(vc, buf);
}

/*
 * Many other routines do put_queue, but I think either
 * they produce ASCII, or they produce some user-assigned
 * string, and in both cases we might assume that it is
 * in utf-8 already.
 */
static void to_utf8(struct vc_data *vc, uint c)
{
	if (c < 0x80)
		/*  0******* */
		put_queue(vc, c);
	else if (c < 0x800) {
		/* 110***** 10****** */
		put_queue(vc, 0xc0 | (c >> 6));
		put_queue(vc, 0x80 | (c & 0x3f));
    	} else if (c < 0x10000) {
	       	if (c >= 0xD800 && c < 0xE000)
			return;
		if (c == 0xFFFF)
			return;
		/* 1110**** 10****** 10****** */
		put_queue(vc, 0xe0 | (c >> 12));
		put_queue(vc, 0x80 | ((c >> 6) & 0x3f));
		put_queue(vc, 0x80 | (c & 0x3f));
    	} else if (c < 0x110000) {
		/* 11110*** 10****** 10****** 10****** */
		put_queue(vc, 0xf0 | (c >> 18));
		put_queue(vc, 0x80 | ((c >> 12) & 0x3f));
		put_queue(vc, 0x80 | ((c >> 6) & 0x3f));
		put_queue(vc, 0x80 | (c & 0x3f));
	}
}

/*
 * Called after returning from RAW mode or when changing consoles - recompute
 * shift_down[] and shift_state from key_down[] maybe called when keymap is
 * undefined, so that shiftkey release is seen
 */
void compute_shiftstate(void)
{
	unsigned int i, j, k, sym, val;

	shift_state = 0;
	memset(shift_down, 0, sizeof(shift_down));

	for (i = 0; i < ARRAY_SIZE(key_down); i++) {

		if (!key_down[i])
			continue;

		k = i * BITS_PER_LONG;

		for (j = 0; j < BITS_PER_LONG; j++, k++) {

			if (!test_bit(k, key_down))
				continue;

			sym = U(key_maps[0][k]);
			if (KTYP(sym) != KT_SHIFT && KTYP(sym) != KT_SLOCK)
				continue;

			val = KVAL(sym);
			if (val == KVAL(K_CAPSSHIFT))
				val = KVAL(K_SHIFT);

			shift_down[val]++;
			shift_state |= (1 << val);
		}
	}
}

/*
 * We have a combining character DIACR here, followed by the character CH.
 * If the combination occurs in the table, return the corresponding value.
 * Otherwise, if CH is a space or equals DIACR, return DIACR.
 * Otherwise, conclude that DIACR was not combining after all,
 * queue it and return CH.
 */
static unsigned int handle_diacr(struct vc_data *vc, unsigned int ch)
{
	unsigned int d = diacr;
	unsigned int i;

	diacr = 0;

	if ((d & ~0xff) == BRL_UC_ROW) {
		if ((ch & ~0xff) == BRL_UC_ROW)
			return d | ch;
	} else {
		for (i = 0; i < accent_table_size; i++)
			if (accent_table[i].diacr == d && accent_table[i].base == ch)
				return accent_table[i].result;
	}

	if (ch == ' ' || ch == (BRL_UC_ROW|0) || ch == d)
		return d;

	if (kbd->kbdmode == VC_UNICODE)
		to_utf8(vc, d);
	else {
		int c = conv_uni_to_8bit(d);
		if (c != -1)
			put_queue(vc, c);
	}

	return ch;
}

/*
 * Special function handlers
 */
static void fn_enter(struct vc_data *vc)
{
	if (diacr) {
		if (kbd->kbdmode == VC_UNICODE)
			to_utf8(vc, diacr);
		else {
			int c = conv_uni_to_8bit(diacr);
			if (c != -1)
				put_queue(vc, c);
		}
		diacr = 0;
	}
	put_queue(vc, 13);
	if (vc_kbd_mode(kbd, VC_CRLF))
		put_queue(vc, 10);
}

static void fn_caps_toggle(struct vc_data *vc)
{
	if (rep)
		return;
	chg_vc_kbd_led(kbd, VC_CAPSLOCK);
}

static void fn_caps_on(struct vc_data *vc)
{
	if (rep)
		return;
	set_vc_kbd_led(kbd, VC_CAPSLOCK);
}

static void fn_show_ptregs(struct vc_data *vc)
{
	struct pt_regs *regs = get_irq_regs();
	if (regs)
		show_regs(regs);
}