pc_keyb.c

RTEMS (Real-Time Executive for Multiprocessor Systems) is a free open source real-time operating sys

	do {
		/*
		 * "handle_kbd_event()" will handle any incoming events
		 * while we wait - keypresses or mouse movement.
		 */
		unsigned char status = handle_kbd_event();

		if (! (status & KBD_STAT_IBF))
			return;
		mdelay(1);
		timeout--;
	} while (timeout);
#ifdef KBD_REPORT_TIMEOUTS
	printk( "Keyboard timed out[1]\n");
#endif
}


/*
 * This reads the keyboard status port, and does the
 * appropriate action.
 *
 * It requires that we hold the keyboard controller
 * spinlock.
 */
static unsigned char handle_kbd_event(void)
{
	unsigned char status = kbd_read_status();
	unsigned int work = 10000;

	while (status & KBD_STAT_OBF) {
		unsigned char scancode;

		scancode = kbd_read_input();
		if (status & KBD_STAT_MOUSE_OBF) {
#if 0
			handle_mouse_event(scancode);
#endif
		} else {
			if (do_acknowledge(scancode))
				handle_scancode(scancode, !(scancode & 0x80));
			mark_bh(KEYBOARD_BH);
		}

		status = kbd_read_status();
		
		if(!work--)
		{
			printk( "pc_keyb: controller jammed (0x%02X).\n", status);
			break;
		}
      return status;
	}

   /* 
    * the commands to set the leds for some reason, returns 0x14, 0x16 
    * and I am intepreting as an ACK, because the original code from
    * Linux was timeing out here... 
    */
	acknowledge = 1;
	reply_expected = 0;
	resend = 0;
	return status;
}


void keyboard_interrupt( void )
{
	handle_kbd_event();
}

/*
 * send_data sends a character to the keyboard and waits
 * for an acknowledge, possibly retrying if asked to. Returns
 * the success status.
 *
 * Don't use 'jiffies', so that we don't depend on interrupts
 */
static int send_data(unsigned char data)
{
	int retries = 3;

	do {
		unsigned long timeout = KBD_TIMEOUT;

		acknowledge = 0; /* Set by interrupt routine on receipt of ACK. */
		resend = 0;
		reply_expected = 1;
		kbd_write_output_w(data);
		for (;;) {
			if (acknowledge)
				return 1;
			if (resend)
				break;
			mdelay(1);
			if (!--timeout) {
#ifdef KBD_REPORT_TIMEOUTS
				printk("Keyboard timeout[2]\n");
#endif
				return 0;
			}
		}
	} while (retries-- > 0);
#ifdef KBD_REPORT_TIMEOUTS
	printk( "keyboard: Too many NACKs -- noisy kbd cable?\n");
#endif
	return 0;
}

void pckbd_leds(unsigned char leds)
{
	if (!send_data(KBD_CMD_SET_LEDS) || !send_data(leds))
	    send_data(KBD_CMD_ENABLE);	/* re-enable kbd if any errors */
}

/*
 * In case we run on a non-x86 hardware we need to initialize both the
 * keyboard controller and the keyboard.  On a x86, the BIOS will
 * already have initialized them.
 *
 * Some x86 BIOSes do not correctly initialize the keyboard, so the
 * "kbd-reset" command line options can be given to force a reset.
 * [Ranger]
 */
#ifdef __i386__
 int kbd_startup_reset = 0;
#else
 int kbd_startup_reset = 1;
#endif

/* for "kbd-reset" cmdline param */
void kbd_reset_setup(char *str, int *ints)
{
	kbd_startup_reset = 1;
}

#define KBD_NO_DATA	(-1)	/* No data */
#define KBD_BAD_DATA	(-2)	/* Parity or other error */

static int kbd_read_data(void)
{
	int retval = KBD_NO_DATA;
	unsigned char status;

	status = kbd_read_status();
	if (status & KBD_STAT_OBF) {
		unsigned char data = kbd_read_input();

		retval = data;
		if (status & (KBD_STAT_GTO | KBD_STAT_PERR))
			retval = KBD_BAD_DATA;
	}
	return retval;
}

static void kbd_clear_input(void)
{
	int maxread = 100;	/* Random number */

	do {
		if (kbd_read_data() == KBD_NO_DATA)
			break;
	} while (--maxread);
}

static int kbd_wait_for_input(void)
{
	long timeout = KBD_INIT_TIMEOUT;

	do {
		int retval = kbd_read_data();
		if (retval >= 0)
			return retval;
		mdelay(1);
	} while (--timeout);
	return -1;
}

static void kbd_write_command_w(int data)
{
	kb_wait();
	kbd_write_command(data);
}

static void kbd_write_output_w(int data)
{
	kb_wait();
	kbd_write_output(data);
}

static char * initialize_kbd(void)
{
	int status;

	/*
	 * 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 "Keyboard 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 "Keyboard interface failed self test";

	/*
	 * Enable the keyboard by allowing the keyboard clock to run.
	 */
	kbd_write_command_w(KBD_CCMD_KBD_ENABLE);

	/*
	 * 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)
			return "Keyboard reset failed, no ACK";
	} while (1);

	if (kbd_wait_for_input() != KBD_REPLY_POR)
		return "Keyboard 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 "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);

	/* ibm 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 "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 "Set rate: no ACK";
	kbd_write_output_w(0x00);
	if (kbd_wait_for_input() != KBD_REPLY_ACK)
		return "Set rate: no ACK";
	return NULL;
}


void pckbd_init_hw(void)
{
	/* kbd_request_region();  */

	/*  Flush any pending input. */
	kbd_clear_input();

	if (kbd_startup_reset) {
		char *msg = initialize_kbd();
		if (msg)
			printk( "initialize_kbd: %s\n", msg);
	}

#if defined CONFIG_PSMOUSE
	psaux_init();
#endif

	/* Ok, finally allocate the IRQ, and off we go.. */
#if 0
	kbd_request_irq( keyboard_interrupt );
#endif

}

/*
char BSP_wait_polled_input( void )
{
  int c,level;

  _CPU_ISR_Disable(level);
  while ( ( c= kbd_wait_for_input() ) < 0 )
      continue;
  _CPU_ISR_Enable (level);
  return c;
}
*/