pmc.c
// SPDX-License-Identifier: GPL-2.0
/* pmc - Driver implementation for power management functions
* of Power Management Controller (PMC) on SPARCstation-Voyager.
*
* Copyright (c) 2002 Eric Brower (ebrower@usa.net)
*/
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/pm.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/module.h>
#include <asm/io.h>
#include <asm/oplib.h>
#include <linux/uaccess.h>
#include <asm/auxio.h>
#include <asm/processor.h>
/* Debug
*
* #define PMC_DEBUG_LED
* #define PMC_NO_IDLE
*/
#define PMC_OBPNAME "SUNW,pmc"
#define PMC_DEVNAME "pmc"
#define PMC_IDLE_REG 0x00
#define PMC_IDLE_ON 0x01
static u8 __iomem *regs;
#define pmc_readb(offs) (sbus_readb(regs+offs))
#define pmc_writeb(val, offs) (sbus_writeb(val, regs+offs))
/*
* CPU idle callback function
* See .../arch/sparc/kernel/process.c
*/
static void pmc_swift_idle(void)
{
#ifdef PMC_DEBUG_LED
set_auxio(0x00, AUXIO_LED);
#endif
pmc_writeb(pmc_readb(PMC_IDLE_REG) | PMC_IDLE_ON, PMC_IDLE_REG);
#ifdef PMC_DEBUG_LED
set_auxio(AUXIO_LED, 0x00);
#endif
}
static int pmc_probe(struct platform_device *op)
{
regs = of_ioremap(&op->resource[0], 0,
resource_size(&op->resource[0]), PMC_OBPNAME);
if (!regs) {
printk(KERN_ERR "%s: unable to map registers\n", PMC_DEVNAME);
return -ENODEV;
}
#ifndef PMC_NO_IDLE
/* Assign power management IDLE handler */
sparc_idle = pmc_swift_idle;
#endif
printk(KERN_INFO "%s: power management initialized\n", PMC_DEVNAME);
return 0;
}
static const struct of_device_id pmc_match[] = {
{
.name = PMC_OBPNAME,
},
{},
};
MODULE_DEVICE_TABLE(of, pmc_match);
static struct platform_driver pmc_driver = {
.driver = {
.name = "pmc",
.of_match_table = pmc_match,
},
.probe = pmc_probe,
};
static int __init pmc_init(void)
{
return platform_driver_register(&pmc_driver);
}
/* This driver is not critical to the boot process
* and is easiest to ioremap when SBus is already
* initialized, so we install ourselves thusly:
*/
__initcall(pmc_init);