arch/sparc/kernel/power.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* power.c: Power management driver.
   3  *
   4  * Copyright (C) 1999, 2007, 2008 David S. Miller (davem@davemloft.net)
   5  */
   6
   7 #include <linux/kernel.h>
   8 #include <linux/export.h>
   9 #include <linux/init.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/reboot.h>
  12 #include <linux/of_device.h>
  13
  14 #include <asm/prom.h>
  15 #include <asm/io.h>
  16
  17 static void __iomem *power_reg;
  18
  19 static irqreturn_t power_handler(int irq, void *dev_id)
  20 {
  21         orderly_poweroff(true);
  22
  23         /* FIXME: Check registers for status... */
  24         return IRQ_HANDLED;
  25 }
  26
  27 static int has_button_interrupt(unsigned int irq, struct device_node *dp)
  28 {
  29         if (irq == 0xffffffff)
  30                 return 0;
  31         if (!of_find_property(dp, "button", NULL))
  32                 return 0;
  33
  34         return 1;
  35 }
  36
  37 static int power_probe(struct platform_device *op)
  38 {
  39         struct resource *res = &op->resource[0];
  40         unsigned int irq = op->archdata.irqs[0];
  41
  42         power_reg = of_ioremap(res, 0, 0x4, "power");
  43
  44         printk(KERN_INFO "%s: Control reg at %llx\n",
  45                op->dev.of_node->name, res->start);
  46
  47         if (has_button_interrupt(irq, op->dev.of_node)) {
  48                 if (request_irq(irq,
  49                                 power_handler, 0, "power", NULL) < 0)
  50                         printk(KERN_ERR "power: Cannot setup IRQ handler.\n");
  51         }
  52
  53         return 0;
  54 }
  55
  56 static const struct of_device_id power_match[] = {
  57         {
  58                 .name = "power",
  59         },
  60         {},
  61 };
  62
  63 static struct platform_driver power_driver = {
  64         .probe          = power_probe,
  65         .driver = {
  66                 .name = "power",
  67                 .of_match_table = power_match,
  68         },
  69 };
  70
  71 builtin_platform_driver(power_driver);