view loadtools/gtapower.c @ 497:74610c4f10f7

target-utils: added 10 ms delay at the end of abb_power_off() The deosmification of the ABB access code (replacement of osmo_delay_ms() bogus delays with correctly-timed ones, which are significantly shorter) had one annoying side effect: when executing the poweroff command from any of the programs, one last '=' prompt character was being sent (and received by the x86 host) as the Calypso board powers off. With delays being shorter now, the abb_power_off() function was returning and the standalone program's main loop was printing its prompt before the Iota chip fully executed the switch-off sequence! I thought about inserting an endless tight loop at the end of the abb_power_off() function, but the implemented solution of a 10 ms delay is a little nicer IMO because if the DEVOFF operation doesn't happen for some reason in a manual hacking scenario, there won't be an artificial blocker in the form of a tight loop keeping us from further poking around.
author Mychaela Falconia <falcon@freecalypso.org>
date Sat, 25 May 2019 20:44:05 +0000
parents e7502631a0f9
children
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/*
 * This module is included only when loadtools are being built to run on the
 * GTA0x application processor (AP).  It provides automated modem power
 * control, i.e., coordinates modem power control with loadtools operations
 * for convenience.
 */

#include <sys/types.h>
#include <sys/file.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

/*
 * Check this pathname: it is correct for the kernel version I'm using
 * on my test GTA02, but it differs for some other kernel versions.
 */
static char modem_powerctl_pathname[] =
	"/sys/bus/platform/devices/gta02-pm-gsm.0/power_on";

void
set_gta_modem_power_ctrl(boolval)
{
	char strbuf[16];
	int len, fd;

	len = sprintf(strbuf, "%d\n", boolval);
	fd = open(modem_powerctl_pathname, O_WRONLY);
	if (fd < 0) {
		perror(modem_powerctl_pathname);
		exit(1);
	}
	write(fd, strbuf, len);
	close(fd);
}

void
fork_gta_modem_poweron()
{
	int i;

	i = fork();
	if (i < 0) {
		perror("fork");
		exit(1);
	}
	if (i)
		return;
	printf("Toggling %s\n", modem_powerctl_pathname);
	set_gta_modem_power_ctrl(0);
	usleep(350000);
	set_gta_modem_power_ctrl(1);
	exit(0);
}