49ab972aea
commit ab772027 (sparc: arch/sparc/kernel/apc.c to unlocked_ioctl)
added lock/unlock_kernel() to the apc ioctl code.
The code needs no serialization at all. Neither put/get_user nor the
read/write access to the sbus devices require it. Remove BKL.
cycle_kernel_lock() was added during the big BKL pushdown. It should
ensure the serializiation against driver init code. In this case there
is nothing to serialize. Remove it as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
192 lines
4.1 KiB
C
192 lines
4.1 KiB
C
/* 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 of_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,
|
|
};
|
|
|
|
static struct miscdevice apc_miscdev = { APC_MINOR, APC_DEVNAME, &apc_fops };
|
|
|
|
static int __devinit apc_probe(struct of_device *op,
|
|
const struct of_device_id *match)
|
|
{
|
|
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 __initdata apc_match[] = {
|
|
{
|
|
.name = APC_OBPNAME,
|
|
},
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, apc_match);
|
|
|
|
static struct of_platform_driver apc_driver = {
|
|
.name = "apc",
|
|
.match_table = apc_match,
|
|
.probe = apc_probe,
|
|
};
|
|
|
|
static int __init apc_init(void)
|
|
{
|
|
return of_register_driver(&apc_driver, &of_bus_type);
|
|
}
|
|
|
|
/* 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);
|