power.c

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/* power.c: Power management driver.
 *
 * Copyright (C) 1999, 2007, 2008 David S. Miller ([email protected])
 */

#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/reboot.h>
#include <linux/of_device.h>

#include <asm/prom.h>
#include <asm/io.h>

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;
}

static int __devinit 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 platform_device *op)
{
    struct resource *res = &op->resource[0];
    unsigned int irq = op->archdata.irqs[0];

    power_reg = of_ioremap(res, 0, 0x4, "power");

    printk(KERN_INFO "%s: Control reg at %llx\n",
           op->dev.of_node->name, res->start);

    if (has_button_interrupt(irq, op->dev.of_node)) {
        if (request_irq(irq,
                power_handler, 0, "power", NULL) < 0)
            printk(KERN_ERR "power: Cannot setup IRQ handler.\n");
    }

    return 0;
}

static const struct of_device_id power_match[] = {
    {
        .name = "power",
    },
    {},
};

static struct platform_driver power_driver = {
    .probe      = power_probe,
    .driver = {
        .name = "power",
        .owner = THIS_MODULE,
        .of_match_table = power_match,
    },
};

static int __init power_init(void)
{
    return platform_driver_register(&power_driver);
}

device_initcall(power_init);