Re: [rft] s2ram wakeup moves to .c, could fix few machines

["H. Peter Anvin" <hpa@xxxxxxxxx>]

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;
		}
	}
}


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