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/*-
* Copyright (c) 1992-1995 Søren Schmidt
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz and Don Ahn.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer
* in this position and unchanged.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This is a modified version of the keyboard reset code used in syscons.
* If the keyboard reset fails, we assume that the keyboard has been
* unplugged and we use a serial port (COM1) as the console instead.
* Returns 1 on failure (no keyboard), 0 on success (keyboard attached).
*
* This grody hack brought to you by Bill Paul (wpaul@ctr.columbia.edu)
*
* $Id: probe_keyboard.c,v 1.2 1997/03/31 03:12:15 weingart Exp $
*/
#ifdef PROBE_KEYBOARD
#include <machine/console.h>
#include <machine/cpufunc.h>
#include "boot.h"
int
probe_keyboard(void)
{
int i, retries = 5;
unsigned char val;
/* flush any noise in the buffer */
while (inb(KB_STAT) & KB_BUF_FULL) {
delay1ms();
(void) inb(KB_DATA);
}
/* Try to reset keyboard hardware */
again:
while (--retries) {
#ifdef DEBUG
printf("%d ", retries);
#endif
while ((inb(KB_STAT) & KB_READY) == KB_READY) delay1ms();
outb(KB_DATA, KB_RESET);
for (i=0; i<1000; i++) {
delay1ms();
val = inb(KB_DATA);
if (val == KB_ACK || val == KB_ECHO)
goto gotack;
if (val == KB_RESEND)
break;
}
}
gotres:
#ifdef DEBUG
printf("gotres\n");
#endif
if (!retries) {
#ifdef DEBUG
printf("gave up\n");
#endif
return(1);
}
gotack:
delay1ms();
while ((inb(KB_STAT) & KB_BUF_FULL) == 0) delay1ms();
delay1ms();
#ifdef DEBUG
printf("ACK ");
#endif
val = inb(KB_DATA);
if (val == KB_ACK)
goto gotack;
if (val == KB_RESEND)
goto again;
if (val != KB_RESET_DONE) {
#ifdef DEBUG
printf("stray val %d\n", val);
#endif
return(0);
}
#ifdef DEBUG
printf("ok\n");
#endif
return(0);
}
#endif /* PROBE_KEYBOARD */
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