/* power.c: Power management driver. * * Copyright (C) 1999, 2007 David S. Miller (davem@davemloft.net) */ #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 <linux/pm.h> #include <linux/syscalls.h> #include <linux/reboot.h> #include <asm/system.h> #include <asm/auxio.h> #include <asm/prom.h> #include <asm/of_device.h> #include <asm/io.h> #include <asm/sstate.h> #include <linux/unistd.h> /* * sysctl - toggle power-off restriction for serial console * systems in machine_power_off() */ int scons_pwroff = 1; static void __iomem *power_reg; static irqreturn_t power_handler(int irq, void *dev_id) { orderly_poweroff(true); /* FIXME: Check registers for status... */ return IRQ_HANDLED; } 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) { sstate_poweroff(); if (strcmp(of_console_device->type, "serial") || scons_pwroff) { 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 { if (poweroff_method != NULL) { poweroff_method(); /* not reached */ } } } machine_halt(); } void (*pm_power_off)(void) = machine_power_off; EXPORT_SYMBOL(pm_power_off); static int __init has_button_interrupt(unsigned int irq, struct device_node *dp) { if (irq == 0xffffffff) return 0; if (!of_find_property(dp, "button", NULL)) return 0; return 1; } static int __devinit power_probe(struct of_device *op, const struct of_device_id *match) { struct resource *res = &op->resource[0]; unsigned int irq= op->irqs[0]; power_reg = of_ioremap(res, 0, 0x4, "power"); printk(KERN_INFO "%s: Control reg at %lx\n", op->node->name, res->start); poweroff_method = machine_halt; /* able to use the standard halt */ if (has_button_interrupt(irq, op->node)) { if (request_irq(irq, power_handler, 0, "power", NULL) < 0) printk(KERN_ERR "power: Cannot setup IRQ handler.\n"); } return 0; } static struct of_device_id power_match[] = { { .name = "power", }, {}, }; static struct of_platform_driver power_driver = { .match_table = power_match, .probe = power_probe, .driver = { .name = "power", }, }; void __init power_init(void) { of_register_driver(&power_driver, &of_platform_bus_type); return; }