lkml.org 
[lkml]   [2008]   [Feb]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [rft] s2ram wakeup moves to .c, could fix few machines
Okay, this uses the iodelay as the timesource... here is the total 
silliness (and totally untested, of course.)

-hpa

static inline void io_delay(void)
{
outb(0, 0x80);
}
static void udelay(int loops)
{
while (loops--)
io_delay(); /* Approximately 1 us */
}
static void beep(unsigned int hz)
{
u8 enable;
if (!hz) {
enable = 0x00; /* Turn off speaker */
} else {
u16 div = 1193181/hz;
outb(0xb6, 0x43); /* Ctr 2, squarewave, load, binary */
io_delay();
outb(div, 0x42); /* LSB of counter */
io_delay();
outb(div >> 8, 0x42); /* MSB of counter */
io_delay();
enable = 0x03; /* Turn on speaker */
}
inb(0x61); /* Dummy read of System Control Port B */
io_delay();
outb(enable, 0x61); /* Enable timer 2 output to speaker */
io_delay();
}
#define DOT_HZ 880
#define DASH_HZ 587
#define US_PER_DOT 125000

/* Okay, this is totally silly, but it's kind of fun. */
void send_morse(const char *pattern)
{
char s;
while ((s = *pattern++)) {
switch (s) {
case '.':
beep(DOT_HZ);
udelay(US_PER_DOT);
beep(0);
udelay(US_PER_DOT);
break;
case '-':
beep(DASH_HZ);
udelay(US_PER_DOT*3);
beep(0);
udelay(US_PER_DOT);
break;
default: /* Assume it's a space */
udelay(US_PER_DOT*3);
break;
}
}
}

\
 
 \ /
  Last update: 2008-02-08 00:17    [from the cache]
©2003-2011 Jasper Spaans