android_kernel_samsung_msm8976/arch/sparc64/kernel/power.c
David S. Miller c73fcc846c [SPARC]: Fix serial console device detection.
The current scheme works on static interpretation of text names, which
is wrong.

The output-device setting, for example, must be resolved via an alias
or similar to a full path name to the console device.

Paths also contain an optional set of 'options', which starts with a
colon at the end of the path.  The option area is used to specify
which of two serial ports ('a' or 'b') the path refers to when a
device node drives multiple ports.  'a' is assumed if the option
specification is missing.

This was caught by the UltraSPARC-T1 simulator.  The 'output-device'
property was set to 'ttya' and we didn't pick upon the fact that this
is an OBP alias set to '/virtual-devices/console'.  Instead we saw it
as the first serial console device, instead of the hypervisor console.

The infrastructure is now there to take advantage of this to resolve
the console correctly even in multi-head situations in fbcon too.

Thanks to Greg Onufer for the bug report.

Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-20 16:59:26 -07:00

117 lines
2.5 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 <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 = {
.name = "power",
.match_table = power_match,
.probe = power_probe,
};
void __init power_init(void)
{
of_register_driver(&power_driver, &of_platform_bus_type);
return;
}