2 * Intel & MS High Precision Event Timer Implementation.
4 * Copyright (C) 2003 Intel Corporation
6 * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
7 * Bob Picco <robert.picco@hp.com>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
14 #include <linux/config.h>
15 #include <linux/interrupt.h>
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/types.h>
19 #include <linux/miscdevice.h>
20 #include <linux/major.h>
21 #include <linux/ioport.h>
22 #include <linux/fcntl.h>
23 #include <linux/init.h>
24 #include <linux/poll.h>
25 #include <linux/proc_fs.h>
26 #include <linux/spinlock.h>
27 #include <linux/sysctl.h>
28 #include <linux/wait.h>
29 #include <linux/bcd.h>
30 #include <linux/seq_file.h>
31 #include <linux/bitops.h>
33 #include <asm/current.h>
34 #include <asm/uaccess.h>
35 #include <asm/system.h>
38 #include <asm/div64.h>
40 #include <linux/acpi.h>
41 #include <acpi/acpi_bus.h>
42 #include <linux/hpet.h>
45 * The High Precision Event Timer driver.
46 * This driver is closely modelled after the rtc.c driver.
47 * http://www.intel.com/hardwaredesign/hpetspec.htm
49 #define HPET_USER_FREQ (64)
50 #define HPET_DRIFT (500)
52 #define HPET_RANGE_SIZE 1024 /* from HPET spec */
54 static u32 hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
56 /* A lock for concurrent access by app and isr hpet activity. */
57 static DEFINE_SPINLOCK(hpet_lock);
58 /* A lock for concurrent intermodule access to hpet and isr hpet activity. */
59 static DEFINE_SPINLOCK(hpet_task_lock);
61 #define HPET_DEV_NAME (7)
64 struct hpets *hd_hpets;
65 struct hpet __iomem *hd_hpet;
66 struct hpet_timer __iomem *hd_timer;
67 unsigned long hd_ireqfreq;
68 unsigned long hd_irqdata;
69 wait_queue_head_t hd_waitqueue;
70 struct fasync_struct *hd_async_queue;
71 struct hpet_task *hd_task;
72 unsigned int hd_flags;
74 unsigned int hd_hdwirq;
75 char hd_name[HPET_DEV_NAME];
79 struct hpets *hp_next;
80 struct hpet __iomem *hp_hpet;
81 unsigned long hp_hpet_phys;
82 struct time_interpolator *hp_interpolator;
83 unsigned long long hp_tick_freq;
84 unsigned long hp_delta;
85 unsigned int hp_ntimer;
86 unsigned int hp_which;
87 struct hpet_dev hp_dev[1];
90 static struct hpets *hpets;
92 #define HPET_OPEN 0x0001
93 #define HPET_IE 0x0002 /* interrupt enabled */
94 #define HPET_PERIODIC 0x0004
95 #define HPET_SHARED_IRQ 0x0008
97 #if BITS_PER_LONG == 64
98 #define write_counter(V, MC) writeq(V, MC)
99 #define read_counter(MC) readq(MC)
101 #define write_counter(V, MC) writel(V, MC)
102 #define read_counter(MC) readl(MC)
106 static inline unsigned long long readq(void __iomem *addr)
108 return readl(addr) | (((unsigned long long)readl(addr + 4)) << 32LL);
113 static inline void writeq(unsigned long long v, void __iomem *addr)
115 writel(v & 0xffffffff, addr);
116 writel(v >> 32, addr + 4);
120 static irqreturn_t hpet_interrupt(int irq, void *data, struct pt_regs *regs)
122 struct hpet_dev *devp;
126 isr = 1 << (devp - devp->hd_hpets->hp_dev);
128 if ((devp->hd_flags & HPET_SHARED_IRQ) &&
129 !(isr & readl(&devp->hd_hpet->hpet_isr)))
132 spin_lock(&hpet_lock);
136 * For non-periodic timers, increment the accumulator.
137 * This has the effect of treating non-periodic like periodic.
139 if ((devp->hd_flags & (HPET_IE | HPET_PERIODIC)) == HPET_IE) {
142 t = devp->hd_ireqfreq;
143 m = read_counter(&devp->hd_hpet->hpet_mc);
144 write_counter(t + m + devp->hd_hpets->hp_delta,
145 &devp->hd_timer->hpet_compare);
148 if (devp->hd_flags & HPET_SHARED_IRQ)
149 writel(isr, &devp->hd_hpet->hpet_isr);
150 spin_unlock(&hpet_lock);
152 spin_lock(&hpet_task_lock);
154 devp->hd_task->ht_func(devp->hd_task->ht_data);
155 spin_unlock(&hpet_task_lock);
157 wake_up_interruptible(&devp->hd_waitqueue);
159 kill_fasync(&devp->hd_async_queue, SIGIO, POLL_IN);
164 static int hpet_open(struct inode *inode, struct file *file)
166 struct hpet_dev *devp;
170 if (file->f_mode & FMODE_WRITE)
173 spin_lock_irq(&hpet_lock);
175 for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
176 for (i = 0; i < hpetp->hp_ntimer; i++)
177 if (hpetp->hp_dev[i].hd_flags & HPET_OPEN
178 || hpetp->hp_dev[i].hd_task)
181 devp = &hpetp->hp_dev[i];
186 spin_unlock_irq(&hpet_lock);
190 file->private_data = devp;
191 devp->hd_irqdata = 0;
192 devp->hd_flags |= HPET_OPEN;
193 spin_unlock_irq(&hpet_lock);
199 hpet_read(struct file *file, char __user *buf, size_t count, loff_t * ppos)
201 DECLARE_WAITQUEUE(wait, current);
204 struct hpet_dev *devp;
206 devp = file->private_data;
207 if (!devp->hd_ireqfreq)
210 if (count < sizeof(unsigned long))
213 add_wait_queue(&devp->hd_waitqueue, &wait);
216 set_current_state(TASK_INTERRUPTIBLE);
218 spin_lock_irq(&hpet_lock);
219 data = devp->hd_irqdata;
220 devp->hd_irqdata = 0;
221 spin_unlock_irq(&hpet_lock);
225 else if (file->f_flags & O_NONBLOCK) {
228 } else if (signal_pending(current)) {
229 retval = -ERESTARTSYS;
235 retval = put_user(data, (unsigned long __user *)buf);
237 retval = sizeof(unsigned long);
239 __set_current_state(TASK_RUNNING);
240 remove_wait_queue(&devp->hd_waitqueue, &wait);
245 static unsigned int hpet_poll(struct file *file, poll_table * wait)
248 struct hpet_dev *devp;
250 devp = file->private_data;
252 if (!devp->hd_ireqfreq)
255 poll_wait(file, &devp->hd_waitqueue, wait);
257 spin_lock_irq(&hpet_lock);
258 v = devp->hd_irqdata;
259 spin_unlock_irq(&hpet_lock);
262 return POLLIN | POLLRDNORM;
267 static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
269 #ifdef CONFIG_HPET_MMAP
270 struct hpet_dev *devp;
273 if (((vma->vm_end - vma->vm_start) != PAGE_SIZE) || vma->vm_pgoff)
276 devp = file->private_data;
277 addr = devp->hd_hpets->hp_hpet_phys;
279 if (addr & (PAGE_SIZE - 1))
282 vma->vm_flags |= VM_IO;
283 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
285 if (io_remap_pfn_range(vma, vma->vm_start, addr >> PAGE_SHIFT,
286 PAGE_SIZE, vma->vm_page_prot)) {
287 printk(KERN_ERR "%s: io_remap_pfn_range failed\n",
298 static int hpet_fasync(int fd, struct file *file, int on)
300 struct hpet_dev *devp;
302 devp = file->private_data;
304 if (fasync_helper(fd, file, on, &devp->hd_async_queue) >= 0)
310 static int hpet_release(struct inode *inode, struct file *file)
312 struct hpet_dev *devp;
313 struct hpet_timer __iomem *timer;
316 devp = file->private_data;
317 timer = devp->hd_timer;
319 spin_lock_irq(&hpet_lock);
321 writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
322 &timer->hpet_config);
327 devp->hd_ireqfreq = 0;
329 if (devp->hd_flags & HPET_PERIODIC
330 && readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
333 v = readq(&timer->hpet_config);
334 v ^= Tn_TYPE_CNF_MASK;
335 writeq(v, &timer->hpet_config);
338 devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC);
339 spin_unlock_irq(&hpet_lock);
344 if (file->f_flags & FASYNC)
345 hpet_fasync(-1, file, 0);
347 file->private_data = NULL;
351 static int hpet_ioctl_common(struct hpet_dev *, int, unsigned long, int);
354 hpet_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
357 struct hpet_dev *devp;
359 devp = file->private_data;
360 return hpet_ioctl_common(devp, cmd, arg, 0);
363 static int hpet_ioctl_ieon(struct hpet_dev *devp)
365 struct hpet_timer __iomem *timer;
366 struct hpet __iomem *hpet;
369 unsigned long g, v, t, m;
370 unsigned long flags, isr;
372 timer = devp->hd_timer;
373 hpet = devp->hd_hpet;
374 hpetp = devp->hd_hpets;
376 if (!devp->hd_ireqfreq)
379 spin_lock_irq(&hpet_lock);
381 if (devp->hd_flags & HPET_IE) {
382 spin_unlock_irq(&hpet_lock);
386 devp->hd_flags |= HPET_IE;
388 if (readl(&timer->hpet_config) & Tn_INT_TYPE_CNF_MASK)
389 devp->hd_flags |= HPET_SHARED_IRQ;
390 spin_unlock_irq(&hpet_lock);
392 irq = devp->hd_hdwirq;
395 unsigned long irq_flags;
397 sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
398 irq_flags = devp->hd_flags & HPET_SHARED_IRQ
399 ? SA_SHIRQ : SA_INTERRUPT;
400 if (request_irq(irq, hpet_interrupt, irq_flags,
401 devp->hd_name, (void *)devp)) {
402 printk(KERN_ERR "hpet: IRQ %d is not free\n", irq);
408 spin_lock_irq(&hpet_lock);
409 devp->hd_flags ^= HPET_IE;
410 spin_unlock_irq(&hpet_lock);
415 t = devp->hd_ireqfreq;
416 v = readq(&timer->hpet_config);
417 g = v | Tn_INT_ENB_CNF_MASK;
419 if (devp->hd_flags & HPET_PERIODIC) {
420 write_counter(t, &timer->hpet_compare);
421 g |= Tn_TYPE_CNF_MASK;
422 v |= Tn_TYPE_CNF_MASK;
423 writeq(v, &timer->hpet_config);
424 v |= Tn_VAL_SET_CNF_MASK;
425 writeq(v, &timer->hpet_config);
426 local_irq_save(flags);
427 m = read_counter(&hpet->hpet_mc);
428 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
430 local_irq_save(flags);
431 m = read_counter(&hpet->hpet_mc);
432 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
435 if (devp->hd_flags & HPET_SHARED_IRQ) {
436 isr = 1 << (devp - devp->hd_hpets->hp_dev);
437 writel(isr, &hpet->hpet_isr);
439 writeq(g, &timer->hpet_config);
440 local_irq_restore(flags);
445 /* converts Hz to number of timer ticks */
446 static inline unsigned long hpet_time_div(struct hpets *hpets,
449 unsigned long long m;
451 m = hpets->hp_tick_freq + (dis >> 1);
453 return (unsigned long)m;
457 hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel)
459 struct hpet_timer __iomem *timer;
460 struct hpet __iomem *hpet;
471 timer = devp->hd_timer;
472 hpet = devp->hd_hpet;
473 hpetp = devp->hd_hpets;
476 return hpet_ioctl_ieon(devp);
485 if ((devp->hd_flags & HPET_IE) == 0)
487 v = readq(&timer->hpet_config);
488 v &= ~Tn_INT_ENB_CNF_MASK;
489 writeq(v, &timer->hpet_config);
491 free_irq(devp->hd_irq, devp);
494 devp->hd_flags ^= HPET_IE;
498 struct hpet_info info;
500 if (devp->hd_ireqfreq)
502 hpet_time_div(hpetp, devp->hd_ireqfreq);
504 info.hi_ireqfreq = 0;
506 readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK;
507 info.hi_hpet = hpetp->hp_which;
508 info.hi_timer = devp - hpetp->hp_dev;
510 memcpy((void *)arg, &info, sizeof(info));
512 if (copy_to_user((void __user *)arg, &info,
518 v = readq(&timer->hpet_config);
519 if ((v & Tn_PER_INT_CAP_MASK) == 0) {
523 devp->hd_flags |= HPET_PERIODIC;
526 v = readq(&timer->hpet_config);
527 if ((v & Tn_PER_INT_CAP_MASK) == 0) {
531 if (devp->hd_flags & HPET_PERIODIC &&
532 readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
533 v = readq(&timer->hpet_config);
534 v ^= Tn_TYPE_CNF_MASK;
535 writeq(v, &timer->hpet_config);
537 devp->hd_flags &= ~HPET_PERIODIC;
540 if (!kernel && (arg > hpet_max_freq) &&
541 !capable(CAP_SYS_RESOURCE)) {
551 devp->hd_ireqfreq = hpet_time_div(hpetp, arg);
557 static struct file_operations hpet_fops = {
558 .owner = THIS_MODULE,
564 .release = hpet_release,
565 .fasync = hpet_fasync,
569 static int hpet_is_known(struct hpet_data *hdp)
573 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
574 if (hpetp->hp_hpet_phys == hdp->hd_phys_address)
580 EXPORT_SYMBOL(hpet_alloc);
581 EXPORT_SYMBOL(hpet_register);
582 EXPORT_SYMBOL(hpet_unregister);
583 EXPORT_SYMBOL(hpet_control);
585 int hpet_register(struct hpet_task *tp, int periodic)
589 struct hpet_timer __iomem *timer;
590 struct hpet_dev *devp;
595 mask = Tn_PER_INT_CAP_MASK;
604 tp->ht_opaque = NULL;
606 spin_lock_irq(&hpet_task_lock);
607 spin_lock(&hpet_lock);
609 for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
610 for (timer = hpetp->hp_hpet->hpet_timers, i = 0;
611 i < hpetp->hp_ntimer; i++, timer++) {
612 if ((readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK)
616 devp = &hpetp->hp_dev[i];
618 if (devp->hd_flags & HPET_OPEN || devp->hd_task) {
623 tp->ht_opaque = devp;
628 spin_unlock(&hpet_lock);
629 spin_unlock_irq(&hpet_task_lock);
637 static inline int hpet_tpcheck(struct hpet_task *tp)
639 struct hpet_dev *devp;
642 devp = tp->ht_opaque;
647 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
648 if (devp >= hpetp->hp_dev
649 && devp < (hpetp->hp_dev + hpetp->hp_ntimer)
650 && devp->hd_hpet == hpetp->hp_hpet)
656 int hpet_unregister(struct hpet_task *tp)
658 struct hpet_dev *devp;
659 struct hpet_timer __iomem *timer;
662 if ((err = hpet_tpcheck(tp)))
665 spin_lock_irq(&hpet_task_lock);
666 spin_lock(&hpet_lock);
668 devp = tp->ht_opaque;
669 if (devp->hd_task != tp) {
670 spin_unlock(&hpet_lock);
671 spin_unlock_irq(&hpet_task_lock);
675 timer = devp->hd_timer;
676 writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
677 &timer->hpet_config);
678 devp->hd_flags &= ~(HPET_IE | HPET_PERIODIC);
679 devp->hd_task = NULL;
680 spin_unlock(&hpet_lock);
681 spin_unlock_irq(&hpet_task_lock);
686 int hpet_control(struct hpet_task *tp, unsigned int cmd, unsigned long arg)
688 struct hpet_dev *devp;
691 if ((err = hpet_tpcheck(tp)))
694 spin_lock_irq(&hpet_lock);
695 devp = tp->ht_opaque;
696 if (devp->hd_task != tp) {
697 spin_unlock_irq(&hpet_lock);
700 spin_unlock_irq(&hpet_lock);
701 return hpet_ioctl_common(devp, cmd, arg, 1);
704 static ctl_table hpet_table[] = {
707 .procname = "max-user-freq",
708 .data = &hpet_max_freq,
709 .maxlen = sizeof(int),
711 .proc_handler = &proc_dointvec,
716 static ctl_table hpet_root[] = {
727 static ctl_table dev_root[] = {
738 static struct ctl_table_header *sysctl_header;
740 static void hpet_register_interpolator(struct hpets *hpetp)
742 #ifdef CONFIG_TIME_INTERPOLATION
743 struct time_interpolator *ti;
745 ti = kzalloc(sizeof(*ti), GFP_KERNEL);
749 ti->source = TIME_SOURCE_MMIO64;
751 ti->addr = &hpetp->hp_hpet->hpet_mc;
752 ti->frequency = hpetp->hp_tick_freq;
753 ti->drift = HPET_DRIFT;
756 hpetp->hp_interpolator = ti;
757 register_time_interpolator(ti);
762 * Adjustment for when arming the timer with
763 * initial conditions. That is, main counter
764 * ticks expired before interrupts are enabled.
766 #define TICK_CALIBRATE (1000UL)
768 static unsigned long hpet_calibrate(struct hpets *hpetp)
770 struct hpet_timer __iomem *timer = NULL;
771 unsigned long t, m, count, i, flags, start;
772 struct hpet_dev *devp;
774 struct hpet __iomem *hpet;
776 for (j = 0, devp = hpetp->hp_dev; j < hpetp->hp_ntimer; j++, devp++)
777 if ((devp->hd_flags & HPET_OPEN) == 0) {
778 timer = devp->hd_timer;
785 hpet = hpetp->hp_hpet;
786 t = read_counter(&timer->hpet_compare);
789 count = hpet_time_div(hpetp, TICK_CALIBRATE);
791 local_irq_save(flags);
793 start = read_counter(&hpet->hpet_mc);
796 m = read_counter(&hpet->hpet_mc);
797 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
798 } while (i++, (m - start) < count);
800 local_irq_restore(flags);
802 return (m - start) / i;
805 int hpet_alloc(struct hpet_data *hdp)
808 struct hpet_dev *devp;
812 struct hpet __iomem *hpet;
813 static struct hpets *last = NULL;
814 unsigned long period;
815 unsigned long long temp;
818 * hpet_alloc can be called by platform dependent code.
819 * If platform dependent code has allocated the hpet that
820 * ACPI has also reported, then we catch it here.
822 if (hpet_is_known(hdp)) {
823 printk(KERN_DEBUG "%s: duplicate HPET ignored\n",
828 siz = sizeof(struct hpets) + ((hdp->hd_nirqs - 1) *
829 sizeof(struct hpet_dev));
831 hpetp = kzalloc(siz, GFP_KERNEL);
836 hpetp->hp_which = hpet_nhpet++;
837 hpetp->hp_hpet = hdp->hd_address;
838 hpetp->hp_hpet_phys = hdp->hd_phys_address;
840 hpetp->hp_ntimer = hdp->hd_nirqs;
842 for (i = 0; i < hdp->hd_nirqs; i++)
843 hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i];
845 hpet = hpetp->hp_hpet;
847 cap = readq(&hpet->hpet_cap);
849 ntimer = ((cap & HPET_NUM_TIM_CAP_MASK) >> HPET_NUM_TIM_CAP_SHIFT) + 1;
851 if (hpetp->hp_ntimer != ntimer) {
852 printk(KERN_WARNING "hpet: number irqs doesn't agree"
853 " with number of timers\n");
859 last->hp_next = hpetp;
865 period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
866 HPET_COUNTER_CLK_PERIOD_SHIFT; /* fs, 10^-15 */
867 temp = 1000000000000000uLL; /* 10^15 femtoseconds per second */
868 temp += period >> 1; /* round */
869 do_div(temp, period);
870 hpetp->hp_tick_freq = temp; /* ticks per second */
872 printk(KERN_INFO "hpet%d: at MMIO 0x%lx (virtual 0x%p), IRQ%s",
873 hpetp->hp_which, hdp->hd_phys_address, hdp->hd_address,
874 hpetp->hp_ntimer > 1 ? "s" : "");
875 for (i = 0; i < hpetp->hp_ntimer; i++)
876 printk("%s %d", i > 0 ? "," : "", hdp->hd_irq[i]);
879 printk(KERN_INFO "hpet%u: %u %d-bit timers, %Lu Hz\n",
880 hpetp->hp_which, hpetp->hp_ntimer,
881 cap & HPET_COUNTER_SIZE_MASK ? 64 : 32, hpetp->hp_tick_freq);
883 mcfg = readq(&hpet->hpet_config);
884 if ((mcfg & HPET_ENABLE_CNF_MASK) == 0) {
885 write_counter(0L, &hpet->hpet_mc);
886 mcfg |= HPET_ENABLE_CNF_MASK;
887 writeq(mcfg, &hpet->hpet_config);
890 for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer; i++, devp++) {
891 struct hpet_timer __iomem *timer;
893 timer = &hpet->hpet_timers[devp - hpetp->hp_dev];
895 devp->hd_hpets = hpetp;
896 devp->hd_hpet = hpet;
897 devp->hd_timer = timer;
900 * If the timer was reserved by platform code,
901 * then make timer unavailable for opens.
903 if (hdp->hd_state & (1 << i)) {
904 devp->hd_flags = HPET_OPEN;
908 init_waitqueue_head(&devp->hd_waitqueue);
911 hpetp->hp_delta = hpet_calibrate(hpetp);
912 hpet_register_interpolator(hpetp);
917 static acpi_status hpet_resources(struct acpi_resource *res, void *data)
919 struct hpet_data *hdp;
921 struct acpi_resource_address64 addr;
925 status = acpi_resource_to_address64(res, &addr);
927 if (ACPI_SUCCESS(status)) {
930 size = addr.max_address_range - addr.min_address_range + 1;
931 hdp->hd_phys_address = addr.min_address_range;
932 hdp->hd_address = ioremap(addr.min_address_range, size);
934 if (hpet_is_known(hdp)) {
935 printk(KERN_DEBUG "%s: 0x%lx is busy\n",
936 __FUNCTION__, hdp->hd_phys_address);
937 iounmap(hdp->hd_address);
940 } else if (res->id == ACPI_RSTYPE_FIXED_MEM32) {
941 struct acpi_resource_fixed_mem32 *fixmem32;
943 fixmem32 = &res->data.fixed_memory32;
947 hdp->hd_phys_address = fixmem32->range_base_address;
948 hdp->hd_address = ioremap(fixmem32->range_base_address,
951 if (hpet_is_known(hdp)) {
952 printk(KERN_DEBUG "%s: 0x%lx is busy\n",
953 __FUNCTION__, hdp->hd_phys_address);
954 iounmap(hdp->hd_address);
957 } else if (res->id == ACPI_RSTYPE_EXT_IRQ) {
958 struct acpi_resource_ext_irq *irqp;
961 irqp = &res->data.extended_irq;
963 if (irqp->number_of_interrupts > 0) {
964 hdp->hd_nirqs = irqp->number_of_interrupts;
966 for (i = 0; i < hdp->hd_nirqs; i++) {
968 acpi_register_gsi(irqp->interrupts[i],
970 irqp->active_high_low);
981 static int hpet_acpi_add(struct acpi_device *device)
984 struct hpet_data data;
986 memset(&data, 0, sizeof(data));
989 acpi_walk_resources(device->handle, METHOD_NAME__CRS,
990 hpet_resources, &data);
992 if (ACPI_FAILURE(result))
995 if (!data.hd_address || !data.hd_nirqs) {
996 printk("%s: no address or irqs in _CRS\n", __FUNCTION__);
1000 return hpet_alloc(&data);
1003 static int hpet_acpi_remove(struct acpi_device *device, int type)
1005 /* XXX need to unregister interpolator, dealloc mem, etc */
1009 static struct acpi_driver hpet_acpi_driver = {
1013 .add = hpet_acpi_add,
1014 .remove = hpet_acpi_remove,
1018 static struct miscdevice hpet_misc = { HPET_MINOR, "hpet", &hpet_fops };
1020 static int __init hpet_init(void)
1024 result = misc_register(&hpet_misc);
1028 sysctl_header = register_sysctl_table(dev_root, 0);
1030 result = acpi_bus_register_driver(&hpet_acpi_driver);
1033 unregister_sysctl_table(sysctl_header);
1034 misc_deregister(&hpet_misc);
1041 static void __exit hpet_exit(void)
1043 acpi_bus_unregister_driver(&hpet_acpi_driver);
1046 unregister_sysctl_table(sysctl_header);
1047 misc_deregister(&hpet_misc);
1052 module_init(hpet_init);
1053 module_exit(hpet_exit);
1054 MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>");
1055 MODULE_LICENSE("GPL");