1/* power.c: Power management driver.
2 *
3 * Copyright (C) 1999, 2007, 2008 David S. Miller (davem@davemloft.net)
4 */
5
6#include <linux/kernel.h>
7#include <linux/export.h>
8#include <linux/init.h>
9#include <linux/interrupt.h>
10#include <linux/reboot.h>
11#include <linux/of_device.h>
12
13#include <asm/prom.h>
14#include <asm/io.h>
15
16static void __iomem *power_reg;
17
18static irqreturn_t power_handler(int irq, void *dev_id)
19{
20	orderly_poweroff(true);
21
22	/* FIXME: Check registers for status... */
23	return IRQ_HANDLED;
24}
25
26static int has_button_interrupt(unsigned int irq, struct device_node *dp)
27{
28	if (irq == 0xffffffff)
29		return 0;
30	if (!of_find_property(dp, "button", NULL))
31		return 0;
32
33	return 1;
34}
35
36static int power_probe(struct platform_device *op)
37{
38	struct resource *res = &op->resource[0];
39	unsigned int irq = op->archdata.irqs[0];
40
41	power_reg = of_ioremap(res, 0, 0x4, "power");
42
43	printk(KERN_INFO "%s: Control reg at %llx\n",
44	       op->dev.of_node->name, res->start);
45
46	if (has_button_interrupt(irq, op->dev.of_node)) {
47		if (request_irq(irq,
48				power_handler, 0, "power", NULL) < 0)
49			printk(KERN_ERR "power: Cannot setup IRQ handler.\n");
50	}
51
52	return 0;
53}
54
55static const struct of_device_id power_match[] = {
56	{
57		.name = "power",
58	},
59	{},
60};
61
62static struct platform_driver power_driver = {
63	.probe		= power_probe,
64	.driver = {
65		.name = "power",
66		.of_match_table = power_match,
67	},
68};
69
70static int __init power_init(void)
71{
72	return platform_driver_register(&power_driver);
73}
74
75device_initcall(power_init);
76