[SPARC]: Fix serial console device detection.
[linux-2.6.git] / arch / sparc64 / kernel / power.c
1 /* power.c: Power management driver.
2  *
3  * Copyright (C) 1999, 2007 David S. Miller (davem@davemloft.net)
4  */
5
6 #include <linux/kernel.h>
7 #include <linux/module.h>
8 #include <linux/init.h>
9 #include <linux/sched.h>
10 #include <linux/signal.h>
11 #include <linux/delay.h>
12 #include <linux/interrupt.h>
13 #include <linux/pm.h>
14 #include <linux/syscalls.h>
15 #include <linux/reboot.h>
16
17 #include <asm/system.h>
18 #include <asm/auxio.h>
19 #include <asm/prom.h>
20 #include <asm/of_device.h>
21 #include <asm/io.h>
22 #include <asm/sstate.h>
23
24 #include <linux/unistd.h>
25
26 /*
27  * sysctl - toggle power-off restriction for serial console 
28  * systems in machine_power_off()
29  */
30 int scons_pwroff = 1; 
31
32 static void __iomem *power_reg;
33
34 static irqreturn_t power_handler(int irq, void *dev_id)
35 {
36         orderly_poweroff(true);
37
38         /* FIXME: Check registers for status... */
39         return IRQ_HANDLED;
40 }
41
42 extern void machine_halt(void);
43 extern void machine_alt_power_off(void);
44 static void (*poweroff_method)(void) = machine_alt_power_off;
45
46 void machine_power_off(void)
47 {
48         sstate_poweroff();
49         if (strcmp(of_console_device->type, "serial") || scons_pwroff) {
50                 if (power_reg) {
51                         /* Both register bits seem to have the
52                          * same effect, so until I figure out
53                          * what the difference is...
54                          */
55                         writel(AUXIO_PCIO_CPWR_OFF | AUXIO_PCIO_SPWR_OFF, power_reg);
56                 } else {
57                         if (poweroff_method != NULL) {
58                                 poweroff_method();
59                                 /* not reached */
60                         }
61                 }
62         }
63         machine_halt();
64 }
65
66 void (*pm_power_off)(void) = machine_power_off;
67 EXPORT_SYMBOL(pm_power_off);
68
69 static int __init has_button_interrupt(unsigned int irq, struct device_node *dp)
70 {
71         if (irq == 0xffffffff)
72                 return 0;
73         if (!of_find_property(dp, "button", NULL))
74                 return 0;
75
76         return 1;
77 }
78
79 static int __devinit power_probe(struct of_device *op, const struct of_device_id *match)
80 {
81         struct resource *res = &op->resource[0];
82         unsigned int irq= op->irqs[0];
83
84         power_reg = of_ioremap(res, 0, 0x4, "power");
85
86         printk(KERN_INFO "%s: Control reg at %lx\n",
87                op->node->name, res->start);
88
89         poweroff_method = machine_halt;  /* able to use the standard halt */
90
91         if (has_button_interrupt(irq, op->node)) {
92                 if (request_irq(irq,
93                                 power_handler, 0, "power", NULL) < 0)
94                         printk(KERN_ERR "power: Cannot setup IRQ handler.\n");
95         }
96
97         return 0;
98 }
99
100 static struct of_device_id power_match[] = {
101         {
102                 .name = "power",
103         },
104         {},
105 };
106
107 static struct of_platform_driver power_driver = {
108         .name           = "power",
109         .match_table    = power_match,
110         .probe          = power_probe,
111 };
112
113 void __init power_init(void)
114 {
115         of_register_driver(&power_driver, &of_platform_bus_type);
116         return;
117 }