kbd.c

U-BOOT,著名的Bootloader程序

	}
	if (e0 == 1) {
		e0 = 0;		/* delete flag */
		if (!(((scancode & 0x7F) == 0x38) ||	/* the right ctrl key */
		      ((scancode & 0x7F) == 0x1D) ||	/* the right alt key */
		      ((scancode & 0x7F) == 0x35) ||	/* the right '/' key */
		      ((scancode & 0x7F) == 0x1C)))
			/* the right enter key */
			/* we swallow unknown e0 codes */
			return;
	}
	/* special cntrl keys */
	switch (scancode) {
	case 0x2A:
	case 0x36:		/* shift pressed */
		shift = 1;
		return;		/* do nothing else */
	case 0xAA:
	case 0xB6:		/* shift released */
		shift = 0;
		return;		/* do nothing else */
	case 0x38:		/* alt pressed */
		alt = 1;
		return;		/* do nothing else */
	case 0xB8:		/* alt released */
		alt = 0;
		return;		/* do nothing else */
	case 0x1d:		/* ctrl pressed */
		ctrl = 1;
		return;		/* do nothing else */
	case 0x9d:		/* ctrl released */
		ctrl = 0;
		return;		/* do nothing else */
	case 0x46:		/* scrollock pressed */
		scroll_lock = ~scroll_lock;
		kbd_set_leds ();
		return;		/* do nothing else */
	case 0x3A:		/* capslock pressed */
		caps_lock = ~caps_lock;
		kbd_set_leds ();
		return;
	case 0x45:		/* numlock pressed */
		num_lock = ~num_lock;
		kbd_set_leds ();
		return;
	case 0xC6:		/* scroll lock released */
	case 0xC5:		/* num lock released */
	case 0xBA:		/* caps lock released */
		return;		/* just swallow */
	}
	if ((scancode & 0x80) == 0x80)	/* key released */
		return;
	/* now, decide which table we need */
	if (scancode > (sizeof (kbd_plain_xlate) / sizeof (kbd_plain_xlate[0]))) {	/* scancode not in list */
		PRINTF ("unkown scancode %X\n", scancode);
		return;		/* swallow it */
	}
	/* setup plain code first */
	keycode = kbd_plain_xlate[scancode];
	if (caps_lock == 1) {	/* caps_lock is pressed, overwrite plain code */
		if (scancode > (sizeof (kbd_shift_xlate) / sizeof (kbd_shift_xlate[0]))) {	/* scancode not in list */
			PRINTF ("unkown caps-locked scancode %X\n", scancode);
			return;	/* swallow it */
		}
		keycode = kbd_shift_xlate[scancode];
		if (keycode < 'A') {	/* we only want the alphas capital */
			keycode = kbd_plain_xlate[scancode];
		}
	}
	if (shift == 1) {	/* shift overwrites caps_lock */
		if (scancode > (sizeof (kbd_shift_xlate) / sizeof (kbd_shift_xlate[0]))) {	/* scancode not in list */
			PRINTF ("unkown shifted scancode %X\n", scancode);
			return;	/* swallow it */
		}
		keycode = kbd_shift_xlate[scancode];
	}
	if (ctrl == 1) {	/* ctrl overwrites caps_lock and shift */
		if (scancode > (sizeof (kbd_ctrl_xlate) / sizeof (kbd_ctrl_xlate[0]))) {	/* scancode not in list */
			PRINTF ("unkown ctrl scancode %X\n", scancode);
			return;	/* swallow it */
		}
		keycode = kbd_ctrl_xlate[scancode];
	}
	/* check if valid keycode */
	if (keycode == 0xff) {
		PRINTF ("unkown scancode %X\n", scancode);
		return;		/* swallow unknown codes */
	}

	kbd_put_queue (keycode);
	PRINTF ("%x\n", keycode);
}

/*
 * This reads the keyboard status port, and does the
 * appropriate action.
 *
 */
unsigned char handle_kbd_event(void)
{
	unsigned char status = kbd_read_status();
	unsigned int work = 10000;

	while ((--work > 0) && (status & KBD_STAT_OBF)) {
		unsigned char scancode;

		scancode = kbd_read_input();

		/* Error bytes must be ignored to make the
		   Synaptics touchpads compaq use work */
		/* Ignore error bytes */
		if (!(status & (KBD_STAT_GTO | KBD_STAT_PERR)))
		{
			if (status & KBD_STAT_MOUSE_OBF)
				; /* not supported: handle_mouse_event(scancode); */
			else
				handle_keyboard_event(scancode);
		}
		status = kbd_read_status();
	}
	if (!work)
		PRINTF("pc_keyb: controller jammed (0x%02X).\n", status);
	return status;
}


/******************************************************************************
 * Lowlevel Part of keyboard section
 */
unsigned char kbd_read_status(void)
{
	return(in8(CFG_ISA_IO_BASE_ADDRESS + KDB_COMMAND_PORT));
}

unsigned char kbd_read_input(void)
{
	return(in8(CFG_ISA_IO_BASE_ADDRESS + KDB_DATA_PORT));
}

void kbd_write_command(unsigned char cmd)
{
	out8(CFG_ISA_IO_BASE_ADDRESS + KDB_COMMAND_PORT,cmd);
}

void kbd_write_output(unsigned char data)
{
	out8(CFG_ISA_IO_BASE_ADDRESS + KDB_DATA_PORT, data);
}

int kbd_read_data(void)
{
	int val;
	unsigned char status;

	val = -1;
	status = kbd_read_status();
	if (status & KBD_STAT_OBF) {
		val = kbd_read_input();
		if (status & (KBD_STAT_GTO | KBD_STAT_PERR))
			val = -2;
	}
	return val;
}

int kbd_wait_for_input(void)
{
	unsigned long timeout;
	int val;

	timeout = KBD_TIMEOUT;
	val=kbd_read_data();
	while(val < 0)
	{
		if(timeout--==0)
			return -1;
		udelay(1000);
		val=kbd_read_data();
	}
	return val;
}


int kb_wait(void)
{
	unsigned long timeout = KBC_TIMEOUT * 10;

	do {
		unsigned char status = handle_kbd_event();
		if (!(status & KBD_STAT_IBF))
			return 0; /* ok */
		udelay(1000);
		timeout--;
	} while (timeout);
	return 1;
}

void kbd_write_command_w(int data)
{
	if(kb_wait())
		PRINTF("timeout in kbd_write_command_w\n");
	kbd_write_command(data);
}

void kbd_write_output_w(int data)
{
	if(kb_wait())
		PRINTF("timeout in kbd_write_output_w\n");
	kbd_write_output(data);
}

void kbd_send_data(unsigned char data)
{
	unsigned char status;
	disable_8259A_irq(1); /* disable interrupt */
	kbd_write_output_w(data);
	status = kbd_wait_for_input();
	if (status == KBD_REPLY_ACK)
		enable_8259A_irq(1); /* enable interrupt */
}


char * kbd_initialize(void)
{
	int status;

	in_pointer = 0; /* delete in Buffer */
	out_pointer = 0;
	/*
	 * Test the keyboard interface.
	 * This seems to be the only way to get it going.
	 * If the test is successful a x55 is placed in the input buffer.
	 */
	kbd_write_command_w(KBD_CCMD_SELF_TEST);
	if (kbd_wait_for_input() != 0x55)
		return "Kbd:   failed self test";
	/*
	 * Perform a keyboard interface test.  This causes the controller
	 * to test the keyboard clock and data lines.  The results of the
	 * test are placed in the input buffer.
	 */
	kbd_write_command_w(KBD_CCMD_KBD_TEST);
	if (kbd_wait_for_input() != 0x00)
		return "Kbd:   interface failed self test";
	/*
	 * Enable the keyboard by allowing the keyboard clock to run.
	 */
	kbd_write_command_w(KBD_CCMD_KBD_ENABLE);
	status = kbd_wait_for_input();
	/*
	 * Reset keyboard. If the read times out
	 * then the assumption is that no keyboard is
	 * plugged into the machine.
	 * This defaults the keyboard to scan-code set 2.
	 *
	 * Set up to try again if the keyboard asks for RESEND.
	 */
	do {
		kbd_write_output_w(KBD_CMD_RESET);
		status = kbd_wait_for_input();
		if (status == KBD_REPLY_ACK)
			break;
		if (status != KBD_REPLY_RESEND) {
			PRINTF("status: %X\n",status);
			return "Kbd:   reset failed, no ACK";
		}
	} while (1);
	if (kbd_wait_for_input() != KBD_REPLY_POR)
		return "Kbd:   reset failed, no POR";

	/*
	 * Set keyboard controller mode. During this, the keyboard should be
	 * in the disabled state.
	 *
	 * Set up to try again if the keyboard asks for RESEND.
	 */
	do {
		kbd_write_output_w(KBD_CMD_DISABLE);
		status = kbd_wait_for_input();
		if (status == KBD_REPLY_ACK)
			break;
		if (status != KBD_REPLY_RESEND)
			return "Kbd:   disable keyboard: no ACK";
	} while (1);

	kbd_write_command_w(KBD_CCMD_WRITE_MODE);
	kbd_write_output_w(KBD_MODE_KBD_INT
			      | KBD_MODE_SYS
			      | KBD_MODE_DISABLE_MOUSE
			      | KBD_MODE_KCC);

	/* AMCC powerpc portables need this to use scan-code set 1 -- Cort */
	kbd_write_command_w(KBD_CCMD_READ_MODE);
	if (!(kbd_wait_for_input() & KBD_MODE_KCC)) {
		/*
		 * If the controller does not support conversion,
		 * Set the keyboard to scan-code set 1.
		 */
		kbd_write_output_w(0xF0);
		kbd_wait_for_input();
		kbd_write_output_w(0x01);
		kbd_wait_for_input();
	}
	kbd_write_output_w(KBD_CMD_ENABLE);
	if (kbd_wait_for_input() != KBD_REPLY_ACK)
		return "Kbd:   enable keyboard: no ACK";

	/*
	 * Finally, set the typematic rate to maximum.
	 */
	kbd_write_output_w(KBD_CMD_SET_RATE);
	if (kbd_wait_for_input() != KBD_REPLY_ACK)
		return "Kbd:   Set rate: no ACK";
	kbd_write_output_w(0x00);
	if (kbd_wait_for_input() != KBD_REPLY_ACK)
		return "Kbd:   Set rate: no ACK";
	return NULL;
}

void kbd_interrupt(void)
{
	handle_kbd_event();
}