blob: 1e34f29e58bb723537429dd0aacb9e0fe7df11b9 [file] [log] [blame]
/* apc - Driver implementation for power management functions
* of Aurora Personality Chip (APC) on SPARCstation-4/5 and
* derivatives.
*
* 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/miscdevice.h>
#include <linux/pm.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <asm/io.h>
#include <asm/oplib.h>
#include <asm/uaccess.h>
#include <asm/auxio.h>
#include <asm/apc.h>
/* Debugging
*
* #define APC_DEBUG_LED
*/
#define APC_MINOR MISC_DYNAMIC_MINOR
#define APC_OBPNAME "power-management"
#define APC_DEVNAME "apc"
static u8 __iomem *regs;
static int apc_no_idle __devinitdata = 0;
#define apc_readb(offs) (sbus_readb(regs+offs))
#define apc_writeb(val, offs) (sbus_writeb(val, regs+offs))
/* Specify "apc=noidle" on the kernel command line to
* disable APC CPU standby support. Certain prototype
* systems (SPARCstation-Fox) do not play well with APC
* CPU idle, so disable this if your system has APC and
* crashes randomly.
*/
static int __init apc_setup(char *str)
{
if(!strncmp(str, "noidle", strlen("noidle"))) {
apc_no_idle = 1;
return 1;
}
return 0;
}
__setup("apc=", apc_setup);
/*
* CPU idle callback function
* See .../arch/sparc/kernel/process.c
*/
static void apc_swift_idle(void)
{
#ifdef APC_DEBUG_LED
set_auxio(0x00, AUXIO_LED);
#endif
apc_writeb(apc_readb(APC_IDLE_REG) | APC_IDLE_ON, APC_IDLE_REG);
#ifdef APC_DEBUG_LED
set_auxio(AUXIO_LED, 0x00);
#endif
}
static inline void apc_free(struct platform_device *op)
{
of_iounmap(&op->resource[0], regs, resource_size(&op->resource[0]));
}
static int apc_open(struct inode *inode, struct file *f)
{
return 0;
}
static int apc_release(struct inode *inode, struct file *f)
{
return 0;
}
static long apc_ioctl(struct file *f, unsigned int cmd, unsigned long __arg)
{
__u8 inarg, __user *arg = (__u8 __user *) __arg;
switch (cmd) {
case APCIOCGFANCTL:
if (put_user(apc_readb(APC_FANCTL_REG) & APC_REGMASK, arg))
return -EFAULT;
break;
case APCIOCGCPWR:
if (put_user(apc_readb(APC_CPOWER_REG) & APC_REGMASK, arg))
return -EFAULT;
break;
case APCIOCGBPORT:
if (put_user(apc_readb(APC_BPORT_REG) & APC_BPMASK, arg))
return -EFAULT;
break;
case APCIOCSFANCTL:
if (get_user(inarg, arg))
return -EFAULT;
apc_writeb(inarg & APC_REGMASK, APC_FANCTL_REG);
break;
case APCIOCSCPWR:
if (get_user(inarg, arg))
return -EFAULT;
apc_writeb(inarg & APC_REGMASK, APC_CPOWER_REG);
break;
case APCIOCSBPORT:
if (get_user(inarg, arg))
return -EFAULT;
apc_writeb(inarg & APC_BPMASK, APC_BPORT_REG);
break;
default:
return -EINVAL;
};
return 0;
}
static const struct file_operations apc_fops = {
.unlocked_ioctl = apc_ioctl,
.open = apc_open,
.release = apc_release,
.llseek = noop_llseek,
};
static struct miscdevice apc_miscdev = { APC_MINOR, APC_DEVNAME, &apc_fops };
static int __devinit apc_probe(struct platform_device *op)
{
int err;
regs = of_ioremap(&op->resource[0], 0,
resource_size(&op->resource[0]), APC_OBPNAME);
if (!regs) {
printk(KERN_ERR "%s: unable to map registers\n", APC_DEVNAME);
return -ENODEV;
}
err = misc_register(&apc_miscdev);
if (err) {
printk(KERN_ERR "%s: unable to register device\n", APC_DEVNAME);
apc_free(op);
return -ENODEV;
}
/* Assign power management IDLE handler */
if (!apc_no_idle)
pm_idle = apc_swift_idle;
printk(KERN_INFO "%s: power management initialized%s\n",
APC_DEVNAME, apc_no_idle ? " (CPU idle disabled)" : "");
return 0;
}
static struct of_device_id apc_match[] = {
{
.name = APC_OBPNAME,
},
{},
};
MODULE_DEVICE_TABLE(of, apc_match);
static struct platform_driver apc_driver = {
.driver = {
.name = "apc",
.owner = THIS_MODULE,
.of_match_table = apc_match,
},
.probe = apc_probe,
};
static int __init apc_init(void)
{
return platform_driver_register(&apc_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(apc_init);