sparc/kernel/power.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /* power.c: Power management driver.
0003  *
0004  * Copyright (C) 1999, 2007, 2008 David S. Miller (davem@davemloft.net)
0005  */
0006
0007 #include <linux/kernel.h>
0008 #include <linux/export.h>
0009 #include <linux/init.h>
0010 #include <linux/interrupt.h>
0011 #include <linux/reboot.h>
0012 #include <linux/of_device.h>
0013
0014 #include <asm/prom.h>
0015 #include <asm/io.h>
0016
0017 static void __iomem *power_reg;
0018
0019 static irqreturn_t power_handler(int irq, void *dev_id)
0020 {
0021     orderly_poweroff(true);
0022
0023     /* FIXME: Check registers for status... */
0024     return IRQ_HANDLED;
0025 }
0026
0027 static int has_button_interrupt(unsigned int irq, struct device_node *dp)
0028 {
0029     if (irq == 0xffffffff)
0030         return 0;
0031     if (!of_find_property(dp, "button", NULL))
0032         return 0;
0033
0034     return 1;
0035 }
0036
0037 static int power_probe(struct platform_device *op)
0038 {
0039     struct resource *res = &op->resource[0];
0040     unsigned int irq = op->archdata.irqs[0];
0041
0042     power_reg = of_ioremap(res, 0, 0x4, "power");
0043
0044     printk(KERN_INFO "%pOFn: Control reg at %llx\n",
0045            op->dev.of_node, res->start);
0046
0047     if (has_button_interrupt(irq, op->dev.of_node)) {
0048         if (request_irq(irq,
0049                 power_handler, 0, "power", NULL) < 0)
0050             printk(KERN_ERR "power: Cannot setup IRQ handler.\n");
0051     }
0052
0053     return 0;
0054 }
0055
0056 static const struct of_device_id power_match[] = {
0057     {
0058         .name = "power",
0059     },
0060     {},
0061 };
0062
0063 static struct platform_driver power_driver = {
0064     .probe      = power_probe,
0065     .driver = {
0066         .name = "power",
0067         .of_match_table = power_match,
0068     },
0069 };
0070
0071 builtin_platform_driver(power_driver);