/* $Id: power.c,v 1.10 2001/12/11 01:57:16 davem Exp $
* power.c: Power management driver.
*
* Copyright (C) 1999 David S. Miller (davem@redhat.com)
*/
#define __KERNEL_SYSCALLS__
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <asm/system.h>
#include <asm/ebus.h>
#include <asm/auxio.h>
#include <linux/unistd.h>
/*
* sysctl - toggle power-off restriction for serial console
* systems in machine_power_off()
*/
int scons_pwroff = 1;
#ifdef CONFIG_PCI
static void __iomem *power_reg;
static DECLARE_WAIT_QUEUE_HEAD(powerd_wait);
static int button_pressed;
static irqreturn_t power_handler(int irq, void *dev_id, struct pt_regs *regs)
{
if (button_pressed == 0) {
button_pressed = 1;
wake_up(&powerd_wait);
}
/* FIXME: Check registers for status... */
return IRQ_HANDLED;
}
#endif /* CONFIG_PCI */
extern void machine_halt(void);
extern void machine_alt_power_off(void);
static void (*poweroff_method)(void) = machine_alt_power_off;
void machine_power_off(void)
{
if (!serial_console || scons_pwroff) {
#ifdef CONFIG_PCI
if (power_reg) {
/* Both register bits seem to have the
* same effect, so until I figure out
* what the difference is...
*/
writel(AUXIO_PCIO_CPWR_OFF | AUXIO_PCIO_SPWR_OFF, power_reg);
} else
#endif /* CONFIG_PCI */
if (poweroff_method != NULL) {
poweroff_method();
/* not reached */
}
}
machine_halt();
}
#ifdef CONFIG_PCI
static int powerd(void *__unused)
{
static char *envp[] = { "HOME=/", "TERM=linux", "PATH=/sbin:/usr/sbin:/bin:/usr/bin", NULL };
char *argv[] = { "/sbin/shutdown", "-h", "now", NULL };
DECLARE_WAITQUEUE(wait, current);
daemonize("powerd");
add_wait_queue(&powerd_wait, &wait);
again:
for (;;) {
set_task_state(current, TASK_INTERRUPTIBLE);
if (button_pressed)
break;
flush_signals(current);
schedule();
}
__set_current_state(TASK_RUNNING);
remove_wait_queue(&powerd_wait, &wait);
/* Ok, down we go... */
button_pressed = 0;
if (execve("/sbin/shutdown", argv, envp) < 0) {
printk("powerd: shutdown execution failed\n");
add_wait_queue(&powerd_wait, &wait);
goto again;
}
return 0;
}
static int __init has_button_interrupt(struct linux_ebus_device *edev)
{
if (edev->irqs[0] == PCI_IRQ_NONE)
return 0;
if (!prom_node_has_property(edev->prom_node, "button"))
return 0;
return 1;
}
void __init power_init(void)
{
struct linux_ebus *ebus;
struct linux_ebus_device *edev;
static int invoked;
if (invoked)
return;
invoked = 1;
for_each_ebus(ebus) {
for_each_ebusdev(edev, ebus) {
if (!strcmp(edev->prom_name, "power"))
goto found;
}
}
return;
found:
power_reg = ioremap(edev->resource[0].start, 0x4);
printk("power: Control reg at %p ... ", power_reg);
poweroff_method = machine_halt; /* able to use the standard halt */
if (has_button_interrupt(edev)) {
if (kernel_thread(powerd, NULL, CLONE_FS) < 0) {
printk("Failed to start power daemon.\n");
return;
}
printk("powerd running.\n");
if (request_irq(edev->irqs[0],
power_handler, SA_SHIRQ, "power", NULL) < 0)
printk("power: Error, cannot register IRQ handler.\n");
} else {
printk("not using powerd.\n");
}
}
#endif /* CONFIG_PCI */
