diff options
| -rw-r--r-- | sys/i386/boot/biosboot/probe_keyboard.c | 28 |
1 files changed, 24 insertions, 4 deletions
diff --git a/sys/i386/boot/biosboot/probe_keyboard.c b/sys/i386/boot/biosboot/probe_keyboard.c index d7334359a7a5..29d315147ccb 100644 --- a/sys/i386/boot/biosboot/probe_keyboard.c +++ b/sys/i386/boot/biosboot/probe_keyboard.c @@ -42,7 +42,7 @@ * * This grody hack brought to you by Bill Paul (wpaul@ctr.columbia.edu) * - * $Id: probe_keyboard.c,v 1.1 1995/01/20 07:48:25 wpaul Exp $ + * $Id: probe_keyboard.c,v 1.2 1995/02/15 04:17:59 rich Exp $ */ #include <machine/console.h> @@ -65,6 +65,12 @@ 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 */ while (retries--) { outb(KB_DATA, KB_RESET); @@ -72,11 +78,25 @@ probe_keyboard(void) delay1ms(); val = inb(KB_DATA); if (val == KB_ACK || val == KB_ECHO) - return(0); + goto gotres; if (val == KB_RESEND) - return (1); + break; } } +gotres: + if (!retries) + return(1); + else { +gotack: + delay1ms(); + while ((inb(KB_STAT) & KB_BUF_FULL) == 0) delay1ms(); + delay1ms(); + val = inb(KB_DATA); + if (val == KB_ACK) + goto gotack; + if (val != KB_RESET_DONE) + return(1); + } - return (0); + return(0); } |