blob: 762fa430fb5be3b6a7615eed705e741509475ba7 [file] [log] [blame]
/*
* Intel & MS High Precision Event Timer Implementation.
*
* Copyright (C) 2003 Intel Corporation
* Venki Pallipadi
* (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
* Bob Picco <robert.picco@hp.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/config.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/miscdevice.h>
#include <linux/major.h>
#include <linux/ioport.h>
#include <linux/fcntl.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/sysctl.h>
#include <linux/wait.h>
#include <linux/bcd.h>
#include <linux/seq_file.h>
#include <linux/bitops.h>
#include <asm/current.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/div64.h>
#include <linux/acpi.h>
#include <acpi/acpi_bus.h>
#include <linux/hpet.h>
/*
* The High Precision Event Timer driver.
* This driver is closely modelled after the rtc.c driver.
* http://www.intel.com/labs/platcomp/hpet/hpetspec.htm
*/
#define HPET_USER_FREQ (64)
#define HPET_DRIFT (500)
static u32 hpet_ntimer, hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
/* A lock for concurrent access by app and isr hpet activity. */
static DEFINE_SPINLOCK(hpet_lock);
/* A lock for concurrent intermodule access to hpet and isr hpet activity. */
static DEFINE_SPINLOCK(hpet_task_lock);
#define HPET_DEV_NAME (7)
struct hpet_dev {
struct hpets *hd_hpets;
struct hpet __iomem *hd_hpet;
struct hpet_timer __iomem *hd_timer;
unsigned long hd_ireqfreq;
unsigned long hd_irqdata;
wait_queue_head_t hd_waitqueue;
struct fasync_struct *hd_async_queue;
struct hpet_task *hd_task;
unsigned int hd_flags;
unsigned int hd_irq;
unsigned int hd_hdwirq;
char hd_name[HPET_DEV_NAME];
};
struct hpets {
struct hpets *hp_next;
struct hpet __iomem *hp_hpet;
unsigned long hp_hpet_phys;
struct time_interpolator *hp_interpolator;
unsigned long hp_period;
unsigned long hp_delta;
unsigned int hp_ntimer;
unsigned int hp_which;
struct hpet_dev hp_dev[1];
};
static struct hpets *hpets;
#define HPET_OPEN 0x0001
#define HPET_IE 0x0002 /* interrupt enabled */
#define HPET_PERIODIC 0x0004
#if BITS_PER_LONG == 64
#define write_counter(V, MC) writeq(V, MC)
#define read_counter(MC) readq(MC)
#else
#define write_counter(V, MC) writel(V, MC)
#define read_counter(MC) readl(MC)
#endif
#ifndef readq
static unsigned long long __inline readq(void __iomem *addr)
{
return readl(addr) | (((unsigned long long)readl(addr + 4)) << 32LL);
}
#endif
#ifndef writeq
static void __inline writeq(unsigned long long v, void __iomem *addr)
{
writel(v & 0xffffffff, addr);
writel(v >> 32, addr + 4);
}
#endif
static irqreturn_t hpet_interrupt(int irq, void *data, struct pt_regs *regs)
{
struct hpet_dev *devp;
unsigned long isr;
devp = data;
spin_lock(&hpet_lock);
devp->hd_irqdata++;
/*
* For non-periodic timers, increment the accumulator.
* This has the effect of treating non-periodic like periodic.
*/
if ((devp->hd_flags & (HPET_IE | HPET_PERIODIC)) == HPET_IE) {
unsigned long m, t;
t = devp->hd_ireqfreq;
m = read_counter(&devp->hd_hpet->hpet_mc);
write_counter(t + m + devp->hd_hpets->hp_delta,
&devp->hd_timer->hpet_compare);
}
isr = (1 << (devp - devp->hd_hpets->hp_dev));
writeq(isr, &devp->hd_hpet->hpet_isr);
spin_unlock(&hpet_lock);
spin_lock(&hpet_task_lock);
if (devp->hd_task)
devp->hd_task->ht_func(devp->hd_task->ht_data);
spin_unlock(&hpet_task_lock);
wake_up_interruptible(&devp->hd_waitqueue);
kill_fasync(&devp->hd_async_queue, SIGIO, POLL_IN);
return IRQ_HANDLED;
}
static int hpet_open(struct inode *inode, struct file *file)
{
struct hpet_dev *devp;
struct hpets *hpetp;
int i;
if (file->f_mode & FMODE_WRITE)
return -EINVAL;
spin_lock_irq(&hpet_lock);
for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
for (i = 0; i < hpetp->hp_ntimer; i++)
if (hpetp->hp_dev[i].hd_flags & HPET_OPEN
|| hpetp->hp_dev[i].hd_task)
continue;
else {
devp = &hpetp->hp_dev[i];
break;
}
if (!devp) {
spin_unlock_irq(&hpet_lock);
return -EBUSY;
}
file->private_data = devp;
devp->hd_irqdata = 0;
devp->hd_flags |= HPET_OPEN;
spin_unlock_irq(&hpet_lock);
return 0;
}
static ssize_t
hpet_read(struct file *file, char __user *buf, size_t count, loff_t * ppos)
{
DECLARE_WAITQUEUE(wait, current);
unsigned long data;
ssize_t retval;
struct hpet_dev *devp;
devp = file->private_data;
if (!devp->hd_ireqfreq)
return -EIO;
if (count < sizeof(unsigned long))
return -EINVAL;
add_wait_queue(&devp->hd_waitqueue, &wait);
for ( ; ; ) {
set_current_state(TASK_INTERRUPTIBLE);
spin_lock_irq(&hpet_lock);
data = devp->hd_irqdata;
devp->hd_irqdata = 0;
spin_unlock_irq(&hpet_lock);
if (data)
break;
else if (file->f_flags & O_NONBLOCK) {
retval = -EAGAIN;
goto out;
} else if (signal_pending(current)) {
retval = -ERESTARTSYS;
goto out;
}
schedule();
}
retval = put_user(data, (unsigned long __user *)buf);
if (!retval)
retval = sizeof(unsigned long);
out:
__set_current_state(TASK_RUNNING);
remove_wait_queue(&devp->hd_waitqueue, &wait);
return retval;
}
static unsigned int hpet_poll(struct file *file, poll_table * wait)
{
unsigned long v;
struct hpet_dev *devp;
devp = file->private_data;
if (!devp->hd_ireqfreq)
return 0;
poll_wait(file, &devp->hd_waitqueue, wait);
spin_lock_irq(&hpet_lock);
v = devp->hd_irqdata;
spin_unlock_irq(&hpet_lock);
if (v != 0)
return POLLIN | POLLRDNORM;
return 0;
}
static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
{
#ifdef CONFIG_HPET_MMAP
struct hpet_dev *devp;
unsigned long addr;
if (((vma->vm_end - vma->vm_start) != PAGE_SIZE) || vma->vm_pgoff)
return -EINVAL;
devp = file->private_data;
addr = devp->hd_hpets->hp_hpet_phys;
if (addr & (PAGE_SIZE - 1))
return -ENOSYS;
vma->vm_flags |= VM_IO;
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
addr = __pa(addr);
if (io_remap_pfn_range(vma, vma->vm_start, addr >> PAGE_SHIFT,
PAGE_SIZE, vma->vm_page_prot)) {
printk(KERN_ERR "remap_pfn_range failed in hpet.c\n");
return -EAGAIN;
}
return 0;
#else
return -ENOSYS;
#endif
}
static int hpet_fasync(int fd, struct file *file, int on)
{
struct hpet_dev *devp;
devp = file->private_data;
if (fasync_helper(fd, file, on, &devp->hd_async_queue) >= 0)
return 0;
else
return -EIO;
}
static int hpet_release(struct inode *inode, struct file *file)
{
struct hpet_dev *devp;
struct hpet_timer __iomem *timer;
int irq = 0;
devp = file->private_data;
timer = devp->hd_timer;
spin_lock_irq(&hpet_lock);
writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
&timer->hpet_config);
irq = devp->hd_irq;
devp->hd_irq = 0;
devp->hd_ireqfreq = 0;
if (devp->hd_flags & HPET_PERIODIC
&& readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
unsigned long v;
v = readq(&timer->hpet_config);
v ^= Tn_TYPE_CNF_MASK;
writeq(v, &timer->hpet_config);
}
devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC);
spin_unlock_irq(&hpet_lock);
if (irq)
free_irq(irq, devp);
if (file->f_flags & FASYNC)
hpet_fasync(-1, file, 0);
file->private_data = NULL;
return 0;
}
static int hpet_ioctl_common(struct hpet_dev *, int, unsigned long, int);
static int
hpet_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
unsigned long arg)
{
struct hpet_dev *devp;
devp = file->private_data;
return hpet_ioctl_common(devp, cmd, arg, 0);
}
static int hpet_ioctl_ieon(struct hpet_dev *devp)
{
struct hpet_timer __iomem *timer;
struct hpet __iomem *hpet;
struct hpets *hpetp;
int irq;
unsigned long g, v, t, m;
unsigned long flags, isr;
timer = devp->hd_timer;
hpet = devp->hd_hpet;
hpetp = devp->hd_hpets;
v = readq(&timer->hpet_config);
spin_lock_irq(&hpet_lock);
if (devp->hd_flags & HPET_IE) {
spin_unlock_irq(&hpet_lock);
return -EBUSY;
}
devp->hd_flags |= HPET_IE;
spin_unlock_irq(&hpet_lock);
t = readq(&timer->hpet_config);
irq = devp->hd_hdwirq;
if (irq) {
sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
if (request_irq
(irq, hpet_interrupt, SA_INTERRUPT, devp->hd_name, (void *)devp)) {
printk(KERN_ERR "hpet: IRQ %d is not free\n", irq);
irq = 0;
}
}
if (irq == 0) {
spin_lock_irq(&hpet_lock);
devp->hd_flags ^= HPET_IE;
spin_unlock_irq(&hpet_lock);
return -EIO;
}
devp->hd_irq = irq;
t = devp->hd_ireqfreq;
v = readq(&timer->hpet_config);
g = v | Tn_INT_ENB_CNF_MASK;
if (devp->hd_flags & HPET_PERIODIC) {
write_counter(t, &timer->hpet_compare);
g |= Tn_TYPE_CNF_MASK;
v |= Tn_TYPE_CNF_MASK;
writeq(v, &timer->hpet_config);
v |= Tn_VAL_SET_CNF_MASK;
writeq(v, &timer->hpet_config);
local_irq_save(flags);
m = read_counter(&hpet->hpet_mc);
write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
} else {
local_irq_save(flags);
m = read_counter(&hpet->hpet_mc);
write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
}
isr = (1 << (devp - hpets->hp_dev));
writeq(isr, &hpet->hpet_isr);
writeq(g, &timer->hpet_config);
local_irq_restore(flags);
return 0;
}
static inline unsigned long hpet_time_div(unsigned long dis)
{
unsigned long long m = 1000000000000000ULL;
do_div(m, dis);
return (unsigned long)m;
}
static int
hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel)
{
struct hpet_timer __iomem *timer;
struct hpet __iomem *hpet;
struct hpets *hpetp;
int err;
unsigned long v;
switch (cmd) {
case HPET_IE_OFF:
case HPET_INFO:
case HPET_EPI:
case HPET_DPI:
case HPET_IRQFREQ:
timer = devp->hd_timer;
hpet = devp->hd_hpet;
hpetp = devp->hd_hpets;
break;
case HPET_IE_ON:
return hpet_ioctl_ieon(devp);
default:
return -EINVAL;
}
err = 0;
switch (cmd) {
case HPET_IE_OFF:
if ((devp->hd_flags & HPET_IE) == 0)
break;
v = readq(&timer->hpet_config);
v &= ~Tn_INT_ENB_CNF_MASK;
writeq(v, &timer->hpet_config);
if (devp->hd_irq) {
free_irq(devp->hd_irq, devp);
devp->hd_irq = 0;
}
devp->hd_flags ^= HPET_IE;
break;
case HPET_INFO:
{
struct hpet_info info;
info.hi_ireqfreq = hpet_time_div(hpetp->hp_period *
devp->hd_ireqfreq);
info.hi_flags =
readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK;
info.hi_hpet = devp->hd_hpets->hp_which;
info.hi_timer = devp - devp->hd_hpets->hp_dev;
if (copy_to_user((void __user *)arg, &info, sizeof(info)))
err = -EFAULT;
break;
}
case HPET_EPI:
v = readq(&timer->hpet_config);
if ((v & Tn_PER_INT_CAP_MASK) == 0) {
err = -ENXIO;
break;
}
devp->hd_flags |= HPET_PERIODIC;
break;
case HPET_DPI:
v = readq(&timer->hpet_config);
if ((v & Tn_PER_INT_CAP_MASK) == 0) {
err = -ENXIO;
break;
}
if (devp->hd_flags & HPET_PERIODIC &&
readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
v = readq(&timer->hpet_config);
v ^= Tn_TYPE_CNF_MASK;
writeq(v, &timer->hpet_config);
}
devp->hd_flags &= ~HPET_PERIODIC;
break;
case HPET_IRQFREQ:
if (!kernel && (arg > hpet_max_freq) &&
!capable(CAP_SYS_RESOURCE)) {
err = -EACCES;
break;
}
if (arg & (arg - 1)) {
err = -EINVAL;
break;
}
devp->hd_ireqfreq = hpet_time_div(hpetp->hp_period * arg);
}
return err;
}
static struct file_operations hpet_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.read = hpet_read,
.poll = hpet_poll,
.ioctl = hpet_ioctl,
.open = hpet_open,
.release = hpet_release,
.fasync = hpet_fasync,
.mmap = hpet_mmap,
};
EXPORT_SYMBOL(hpet_alloc);
EXPORT_SYMBOL(hpet_register);
EXPORT_SYMBOL(hpet_unregister);
EXPORT_SYMBOL(hpet_control);
int hpet_register(struct hpet_task *tp, int periodic)
{
unsigned int i;
u64 mask;
struct hpet_timer __iomem *timer;
struct hpet_dev *devp;
struct hpets *hpetp;
switch (periodic) {
case 1:
mask = Tn_PER_INT_CAP_MASK;
break;
case 0:
mask = 0;
break;
default:
return -EINVAL;
}
spin_lock_irq(&hpet_task_lock);
spin_lock(&hpet_lock);
for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
for (timer = hpetp->hp_hpet->hpet_timers, i = 0;
i < hpetp->hp_ntimer; i++, timer++) {
if ((readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK)
!= mask)
continue;
devp = &hpetp->hp_dev[i];
if (devp->hd_flags & HPET_OPEN || devp->hd_task) {
devp = NULL;
continue;
}
tp->ht_opaque = devp;
devp->hd_task = tp;
break;
}
spin_unlock(&hpet_lock);
spin_unlock_irq(&hpet_task_lock);
if (tp->ht_opaque)
return 0;
else
return -EBUSY;
}
static inline int hpet_tpcheck(struct hpet_task *tp)
{
struct hpet_dev *devp;
struct hpets *hpetp;
devp = tp->ht_opaque;
if (!devp)
return -ENXIO;
for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
if (devp >= hpetp->hp_dev
&& devp < (hpetp->hp_dev + hpetp->hp_ntimer)
&& devp->hd_hpet == hpetp->hp_hpet)
return 0;
return -ENXIO;
}
int hpet_unregister(struct hpet_task *tp)
{
struct hpet_dev *devp;
struct hpet_timer __iomem *timer;
int err;
if ((err = hpet_tpcheck(tp)))
return err;
spin_lock_irq(&hpet_task_lock);
spin_lock(&hpet_lock);
devp = tp->ht_opaque;
if (devp->hd_task != tp) {
spin_unlock(&hpet_lock);
spin_unlock_irq(&hpet_task_lock);
return -ENXIO;
}
timer = devp->hd_timer;
writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
&timer->hpet_config);
devp->hd_flags &= ~(HPET_IE | HPET_PERIODIC);
devp->hd_task = NULL;
spin_unlock(&hpet_lock);
spin_unlock_irq(&hpet_task_lock);
return 0;
}
int hpet_control(struct hpet_task *tp, unsigned int cmd, unsigned long arg)
{
struct hpet_dev *devp;
int err;
if ((err = hpet_tpcheck(tp)))
return err;
spin_lock_irq(&hpet_lock);
devp = tp->ht_opaque;
if (devp->hd_task != tp) {
spin_unlock_irq(&hpet_lock);
return -ENXIO;
}
spin_unlock_irq(&hpet_lock);
return hpet_ioctl_common(devp, cmd, arg, 1);
}
static ctl_table hpet_table[] = {
{
.ctl_name = 1,
.procname = "max-user-freq",
.data = &hpet_max_freq,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = &proc_dointvec,
},
{.ctl_name = 0}
};
static ctl_table hpet_root[] = {
{
.ctl_name = 1,
.procname = "hpet",
.maxlen = 0,
.mode = 0555,
.child = hpet_table,
},
{.ctl_name = 0}
};
static ctl_table dev_root[] = {
{
.ctl_name = CTL_DEV,
.procname = "dev",
.maxlen = 0,
.mode = 0555,
.child = hpet_root,
},
{.ctl_name = 0}
};
static struct ctl_table_header *sysctl_header;
static void hpet_register_interpolator(struct hpets *hpetp)
{
#ifdef CONFIG_TIME_INTERPOLATION
struct time_interpolator *ti;
ti = kmalloc(sizeof(*ti), GFP_KERNEL);
if (!ti)
return;
memset(ti, 0, sizeof(*ti));
ti->source = TIME_SOURCE_MMIO64;
ti->shift = 10;
ti->addr = &hpetp->hp_hpet->hpet_mc;
ti->frequency = hpet_time_div(hpets->hp_period);
ti->drift = ti->frequency * HPET_DRIFT / 1000000;
ti->mask = -1;
hpetp->hp_interpolator = ti;
register_time_interpolator(ti);
#endif
}
/*
* Adjustment for when arming the timer with
* initial conditions. That is, main counter
* ticks expired before interrupts are enabled.
*/
#define TICK_CALIBRATE (1000UL)
static unsigned long hpet_calibrate(struct hpets *hpetp)
{
struct hpet_timer __iomem *timer = NULL;
unsigned long t, m, count, i, flags, start;
struct hpet_dev *devp;
int j;
struct hpet __iomem *hpet;
for (j = 0, devp = hpetp->hp_dev; j < hpetp->hp_ntimer; j++, devp++)
if ((devp->hd_flags & HPET_OPEN) == 0) {
timer = devp->hd_timer;
break;
}
if (!timer)
return 0;
hpet = hpets->hp_hpet;
t = read_counter(&timer->hpet_compare);
i = 0;
count = hpet_time_div(hpetp->hp_period * TICK_CALIBRATE);
local_irq_save(flags);
start = read_counter(&hpet->hpet_mc);
do {
m = read_counter(&hpet->hpet_mc);
write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
} while (i++, (m - start) < count);
local_irq_restore(flags);
return (m - start) / i;
}
int hpet_alloc(struct hpet_data *hdp)
{
u64 cap, mcfg;
struct hpet_dev *devp;
u32 i, ntimer;
struct hpets *hpetp;
size_t siz;
struct hpet __iomem *hpet;
static struct hpets *last = (struct hpets *)0;
unsigned long ns;
/*
* hpet_alloc can be called by platform dependent code.
* if platform dependent code has allocated the hpet
* ACPI also reports hpet, then we catch it here.
*/
for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
if (hpetp->hp_hpet == hdp->hd_address)
return 0;
siz = sizeof(struct hpets) + ((hdp->hd_nirqs - 1) *
sizeof(struct hpet_dev));
hpetp = kmalloc(siz, GFP_KERNEL);
if (!hpetp)
return -ENOMEM;
memset(hpetp, 0, siz);
hpetp->hp_which = hpet_nhpet++;
hpetp->hp_hpet = hdp->hd_address;
hpetp->hp_hpet_phys = hdp->hd_phys_address;
hpetp->hp_ntimer = hdp->hd_nirqs;
for (i = 0; i < hdp->hd_nirqs; i++)
hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i];
hpet = hpetp->hp_hpet;
cap = readq(&hpet->hpet_cap);
ntimer = ((cap & HPET_NUM_TIM_CAP_MASK) >> HPET_NUM_TIM_CAP_SHIFT) + 1;
if (hpetp->hp_ntimer != ntimer) {
printk(KERN_WARNING "hpet: number irqs doesn't agree"
" with number of timers\n");
kfree(hpetp);
return -ENODEV;
}
if (last)
last->hp_next = hpetp;
else
hpets = hpetp;
last = hpetp;
hpetp->hp_period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
HPET_COUNTER_CLK_PERIOD_SHIFT;
printk(KERN_INFO "hpet%d: at MMIO 0x%lx, IRQ%s",
hpetp->hp_which, hdp->hd_phys_address,
hpetp->hp_ntimer > 1 ? "s" : "");
for (i = 0; i < hpetp->hp_ntimer; i++)
printk("%s %d", i > 0 ? "," : "", hdp->hd_irq[i]);
printk("\n");
ns = hpetp->hp_period; /* femptoseconds, 10^-15 */
ns /= 1000000; /* convert to nanoseconds, 10^-9 */
printk(KERN_INFO "hpet%d: %ldns tick, %d %d-bit timers\n",
hpetp->hp_which, ns, hpetp->hp_ntimer,
cap & HPET_COUNTER_SIZE_MASK ? 64 : 32);
mcfg = readq(&hpet->hpet_config);
if ((mcfg & HPET_ENABLE_CNF_MASK) == 0) {
write_counter(0L, &hpet->hpet_mc);
mcfg |= HPET_ENABLE_CNF_MASK;
writeq(mcfg, &hpet->hpet_config);
}
for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer;
i++, hpet_ntimer++, devp++) {
unsigned long v;
struct hpet_timer __iomem *timer;
timer = &hpet->hpet_timers[devp - hpetp->hp_dev];
v = readq(&timer->hpet_config);
devp->hd_hpets = hpetp;
devp->hd_hpet = hpet;
devp->hd_timer = timer;
/*
* If the timer was reserved by platform code,
* then make timer unavailable for opens.
*/
if (hdp->hd_state & (1 << i)) {
devp->hd_flags = HPET_OPEN;
continue;
}
init_waitqueue_head(&devp->hd_waitqueue);
}
hpetp->hp_delta = hpet_calibrate(hpetp);
hpet_register_interpolator(hpetp);
return 0;
}
static acpi_status hpet_resources(struct acpi_resource *res, void *data)
{
struct hpet_data *hdp;
acpi_status status;
struct acpi_resource_address64 addr;
struct hpets *hpetp;
hdp = data;
status = acpi_resource_to_address64(res, &addr);
if (ACPI_SUCCESS(status)) {
unsigned long size;
size = addr.max_address_range - addr.min_address_range + 1;
hdp->hd_phys_address = addr.min_address_range;
hdp->hd_address = ioremap(addr.min_address_range, size);
for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
if (hpetp->hp_hpet == hdp->hd_address)
return -EBUSY;
} else if (res->id == ACPI_RSTYPE_EXT_IRQ) {
struct acpi_resource_ext_irq *irqp;
int i;
irqp = &res->data.extended_irq;
if (irqp->number_of_interrupts > 0) {
hdp->hd_nirqs = irqp->number_of_interrupts;
for (i = 0; i < hdp->hd_nirqs; i++)
hdp->hd_irq[i] =
acpi_register_gsi(irqp->interrupts[i],
irqp->edge_level,
irqp->active_high_low);
}
}
return AE_OK;
}
static int hpet_acpi_add(struct acpi_device *device)
{
acpi_status result;
struct hpet_data data;
memset(&data, 0, sizeof(data));
result =
acpi_walk_resources(device->handle, METHOD_NAME__CRS,
hpet_resources, &data);
if (ACPI_FAILURE(result))
return -ENODEV;
if (!data.hd_address || !data.hd_nirqs) {
printk("%s: no address or irqs in _CRS\n", __FUNCTION__);
return -ENODEV;
}
return hpet_alloc(&data);
}
static int hpet_acpi_remove(struct acpi_device *device, int type)
{
/* XXX need to unregister interpolator, dealloc mem, etc */
return -EINVAL;
}
static struct acpi_driver hpet_acpi_driver = {
.name = "hpet",
.ids = "PNP0103",
.ops = {
.add = hpet_acpi_add,
.remove = hpet_acpi_remove,
},
};
static struct miscdevice hpet_misc = { HPET_MINOR, "hpet", &hpet_fops };
static int __init hpet_init(void)
{
int result;
result = misc_register(&hpet_misc);
if (result < 0)
return -ENODEV;
sysctl_header = register_sysctl_table(dev_root, 0);
result = acpi_bus_register_driver(&hpet_acpi_driver);
if (result < 0) {
if (sysctl_header)
unregister_sysctl_table(sysctl_header);
misc_deregister(&hpet_misc);
return result;
}
return 0;
}
static void __exit hpet_exit(void)
{
acpi_bus_unregister_driver(&hpet_acpi_driver);
if (sysctl_header)
unregister_sysctl_table(sysctl_header);
misc_deregister(&hpet_misc);
return;
}
module_init(hpet_init);
module_exit(hpet_exit);
MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>");
MODULE_LICENSE("GPL");