arch/sparc/kernel/power.c

   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 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 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                 .of_match_table = power_match,
  67         },
  68 };
  69
  70 builtin_platform_driver(power_driver);