linux/arch/sparc64/kernel/power.c
David S. Miller 13077d8028 [SPARC64]: Export powerd facilities for external entities.
Besides the existing usage for power-button interrupts, we'll
want to make use of this code for domain-services where the
LDOM manager can send reboot requests to the guest node.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-16 04:04:16 -07:00

176 lines
3.6 KiB
C

/* 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 <asm/system.h>
#include <asm/auxio.h>
#include <asm/prom.h>
#include <asm/of_device.h>
#include <asm/io.h>
#include <asm/power.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 DECLARE_WAIT_QUEUE_HEAD(powerd_wait);
static int button_pressed;
void wake_up_powerd(void)
{
if (button_pressed == 0) {
button_pressed = 1;
wake_up(&powerd_wait);
}
}
static irqreturn_t power_handler(int irq, void *dev_id)
{
wake_up_powerd();
/* 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 (!serial_console || 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 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);
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 (kernel_execve("/sbin/shutdown", argv, envp) < 0) {
printk(KERN_ERR "powerd: shutdown execution failed\n");
machine_power_off();
}
return 0;
}
int start_powerd(void)
{
int err;
err = kernel_thread(powerd, NULL, CLONE_FS);
if (err < 0)
printk(KERN_ERR "power: Failed to start power daemon.\n");
else
printk(KERN_INFO "power: powerd running.\n");
return err;
}
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("%s: Control reg at %lx ... ",
op->node->name, res->start);
poweroff_method = machine_halt; /* able to use the standard halt */
if (has_button_interrupt(irq, op->node)) {
if (start_powerd() < 0)
return 0;
if (request_irq(irq,
power_handler, 0, "power", NULL) < 0)
printk(KERN_ERR "power: Cannot setup IRQ handler.\n");
} else {
printk(KERN_INFO "power: Not using powerd.\n");
}
return 0;
}
static struct of_device_id power_match[] = {
{
.name = "power",
},
{},
};
static struct of_platform_driver power_driver = {
.name = "power",
.match_table = power_match,
.probe = power_probe,
};
void __init power_init(void)
{
of_register_driver(&power_driver, &of_bus_type);
return;
}