/* $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) */ #include <linux/config.h> #include <linux/kernel.h> #include <linux/init.h> #include <linux/sched.h> #include <linux/signal.h> #include <linux/delay.h> #include <asm/system.h> #include <asm/ebus.h> #define __KERNEL_SYSCALLS__ #include <linux/unistd.h> #ifdef CONFIG_PCI static unsigned long power_reg = 0UL; #define POWER_SYSTEM_OFF (1 << 0) #define POWER_COURTESY_OFF (1 << 1) static DECLARE_WAIT_QUEUE_HEAD(powerd_wait); static int button_pressed; static void power_handler(int irq, void *dev_id, struct pt_regs *regs) { if (button_pressed == 0) { wake_up(&powerd_wait); button_pressed = 1; } } #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) { #ifdef CONFIG_PCI if (power_reg != 0UL) { /* Both register bits seem to have the * same effect, so until I figure out * what the difference is... */ writel(POWER_COURTESY_OFF | POWER_SYSTEM_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 }; daemonize(); sprintf(current->comm, "powerd"); again: while (button_pressed == 0) { spin_lock_irq(¤t->sigmask_lock); flush_signals(current); spin_unlock_irq(¤t->sigmask_lock); interruptible_sleep_on(&powerd_wait); } /* Ok, down we go... */ if (execve("/sbin/shutdown", argv, envp) < 0) { printk("powerd: shutdown execution failed\n"); button_pressed = 0; goto again; } return 0; } 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 = (unsigned long)ioremap(edev->resource[0].start, 0x4); printk("power: Control reg at %016lx ... ", power_reg); poweroff_method = machine_halt; /* able to use the standard halt */ if (edev->irqs[0] != PCI_IRQ_NONE) { if (kernel_thread(powerd, 0, 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", (void *) power_reg) < 0) printk("power: Error, cannot register IRQ handler.\n"); } else { printk("not using powerd.\n"); } } #endif /* CONFIG_PCI */