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 16 static void __iomem *power_reg; 17 18 static 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 26 static int __devinit 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 36 static int __devinit 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 55 static const struct of_device_id power_match[] = { 56 { 57 .name = "power", 58 }, 59 {}, 60 }; 61 62 static struct platform_driver power_driver = { 63 .probe = power_probe, 64 .driver = { 65 .name = "power", 66 .owner = THIS_MODULE, 67 .of_match_table = power_match, 68 }, 69 }; 70 71 static int __init power_init(void) 72 { 73 return platform_driver_register(&power_driver); 74 } 75 76 device_initcall(power_init); 77