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.h>
  13 #include <linux/platform_device.h>
  14
  15 #include <asm/prom.h>
  16 #include <asm/io.h>
  17
  18 static void __iomem *power_reg;
  19
  20 static irqreturn_t power_handler(int irq, void *dev_id)
  21 {
  22         orderly_poweroff(true);
  23
  24         /* FIXME: Check registers for status... */
  25         return IRQ_HANDLED;
  26 }
  27
  28 static int has_button_interrupt(unsigned int irq, struct device_node *dp)
  29 {
  30         if (irq == 0xffffffff)
  31                 return 0;
  32         if (!of_property_read_bool(dp, "button"))
  33                 return 0;
  34
  35         return 1;
  36 }
  37
  38 static int power_probe(struct platform_device *op)
  39 {
  40         struct resource *res = &op->resource[0];
  41         unsigned int irq = op->archdata.irqs[0];
  42
  43         power_reg = of_ioremap(res, 0, 0x4, "power");
  44
  45         printk(KERN_INFO "%pOFn: Control reg at %llx\n",
  46                op->dev.of_node, res->start);
  47
  48         if (has_button_interrupt(irq, op->dev.of_node)) {
  49                 if (request_irq(irq,
  50                                 power_handler, 0, "power", NULL) < 0)
  51                         printk(KERN_ERR "power: Cannot setup IRQ handler.\n");
  52         }
  53
  54         return 0;
  55 }
  56
  57 static const struct of_device_id power_match[] = {
  58         {
  59                 .name = "power",
  60         },
  61         {},
  62 };
  63
  64 static struct platform_driver power_driver = {
  65         .probe          = power_probe,
  66         .driver = {
  67                 .name = "power",
  68                 .of_match_table = power_match,
  69         },
  70 };
  71
  72 builtin_platform_driver(power_driver);