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 "remap_pfn_range failed in hpet.c\n");
297 static int hpet_fasync(int fd, struct file *file, int on)
299 struct hpet_dev *devp;
301 devp = file->private_data;
303 if (fasync_helper(fd, file, on, &devp->hd_async_queue) >= 0)
309 static int hpet_release(struct inode *inode, struct file *file)
311 struct hpet_dev *devp;
312 struct hpet_timer __iomem *timer;
315 devp = file->private_data;
316 timer = devp->hd_timer;
318 spin_lock_irq(&hpet_lock);
320 writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
321 &timer->hpet_config);
326 devp->hd_ireqfreq = 0;
328 if (devp->hd_flags & HPET_PERIODIC
329 && readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
332 v = readq(&timer->hpet_config);
333 v ^= Tn_TYPE_CNF_MASK;
334 writeq(v, &timer->hpet_config);
337 devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC);
338 spin_unlock_irq(&hpet_lock);
343 if (file->f_flags & FASYNC)
344 hpet_fasync(-1, file, 0);
346 file->private_data = NULL;
350 static int hpet_ioctl_common(struct hpet_dev *, int, unsigned long, int);
353 hpet_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
356 struct hpet_dev *devp;
358 devp = file->private_data;
359 return hpet_ioctl_common(devp, cmd, arg, 0);
362 static int hpet_ioctl_ieon(struct hpet_dev *devp)
364 struct hpet_timer __iomem *timer;
365 struct hpet __iomem *hpet;
368 unsigned long g, v, t, m;
369 unsigned long flags, isr;
371 timer = devp->hd_timer;
372 hpet = devp->hd_hpet;
373 hpetp = devp->hd_hpets;
375 if (!devp->hd_ireqfreq)
378 spin_lock_irq(&hpet_lock);
380 if (devp->hd_flags & HPET_IE) {
381 spin_unlock_irq(&hpet_lock);
385 devp->hd_flags |= HPET_IE;
387 if (readl(&timer->hpet_config) & Tn_INT_TYPE_CNF_MASK)
388 devp->hd_flags |= HPET_SHARED_IRQ;
389 spin_unlock_irq(&hpet_lock);
391 irq = devp->hd_hdwirq;
394 unsigned long irq_flags;
396 sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
397 irq_flags = devp->hd_flags & HPET_SHARED_IRQ
398 ? SA_SHIRQ : SA_INTERRUPT;
399 if (request_irq(irq, hpet_interrupt, irq_flags,
400 devp->hd_name, (void *)devp)) {
401 printk(KERN_ERR "hpet: IRQ %d is not free\n", irq);
407 spin_lock_irq(&hpet_lock);
408 devp->hd_flags ^= HPET_IE;
409 spin_unlock_irq(&hpet_lock);
414 t = devp->hd_ireqfreq;
415 v = readq(&timer->hpet_config);
416 g = v | Tn_INT_ENB_CNF_MASK;
418 if (devp->hd_flags & HPET_PERIODIC) {
419 write_counter(t, &timer->hpet_compare);
420 g |= Tn_TYPE_CNF_MASK;
421 v |= Tn_TYPE_CNF_MASK;
422 writeq(v, &timer->hpet_config);
423 v |= Tn_VAL_SET_CNF_MASK;
424 writeq(v, &timer->hpet_config);
425 local_irq_save(flags);
426 m = read_counter(&hpet->hpet_mc);
427 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
429 local_irq_save(flags);
430 m = read_counter(&hpet->hpet_mc);
431 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
434 if (devp->hd_flags & HPET_SHARED_IRQ) {
435 isr = 1 << (devp - devp->hd_hpets->hp_dev);
436 writel(isr, &hpet->hpet_isr);
438 writeq(g, &timer->hpet_config);
439 local_irq_restore(flags);
444 /* converts Hz to number of timer ticks */
445 static inline unsigned long hpet_time_div(struct hpets *hpets,
448 unsigned long long m;
450 m = hpets->hp_tick_freq + (dis >> 1);
452 return (unsigned long)m;
456 hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg, int kernel)
458 struct hpet_timer __iomem *timer;
459 struct hpet __iomem *hpet;
470 timer = devp->hd_timer;
471 hpet = devp->hd_hpet;
472 hpetp = devp->hd_hpets;
475 return hpet_ioctl_ieon(devp);
484 if ((devp->hd_flags & HPET_IE) == 0)
486 v = readq(&timer->hpet_config);
487 v &= ~Tn_INT_ENB_CNF_MASK;
488 writeq(v, &timer->hpet_config);
490 free_irq(devp->hd_irq, devp);
493 devp->hd_flags ^= HPET_IE;
497 struct hpet_info info;
499 if (devp->hd_ireqfreq)
501 hpet_time_div(hpetp, devp->hd_ireqfreq);
503 info.hi_ireqfreq = 0;
505 readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK;
506 info.hi_hpet = hpetp->hp_which;
507 info.hi_timer = devp - hpetp->hp_dev;
509 memcpy((void *)arg, &info, sizeof(info));
511 if (copy_to_user((void __user *)arg, &info,
517 v = readq(&timer->hpet_config);
518 if ((v & Tn_PER_INT_CAP_MASK) == 0) {
522 devp->hd_flags |= HPET_PERIODIC;
525 v = readq(&timer->hpet_config);
526 if ((v & Tn_PER_INT_CAP_MASK) == 0) {
530 if (devp->hd_flags & HPET_PERIODIC &&
531 readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
532 v = readq(&timer->hpet_config);
533 v ^= Tn_TYPE_CNF_MASK;
534 writeq(v, &timer->hpet_config);
536 devp->hd_flags &= ~HPET_PERIODIC;
539 if (!kernel && (arg > hpet_max_freq) &&
540 !capable(CAP_SYS_RESOURCE)) {
550 devp->hd_ireqfreq = hpet_time_div(hpetp, arg);
556 static struct file_operations hpet_fops = {
557 .owner = THIS_MODULE,
563 .release = hpet_release,
564 .fasync = hpet_fasync,
568 EXPORT_SYMBOL(hpet_alloc);
569 EXPORT_SYMBOL(hpet_register);
570 EXPORT_SYMBOL(hpet_unregister);
571 EXPORT_SYMBOL(hpet_control);
573 int hpet_register(struct hpet_task *tp, int periodic)
577 struct hpet_timer __iomem *timer;
578 struct hpet_dev *devp;
583 mask = Tn_PER_INT_CAP_MASK;
592 tp->ht_opaque = NULL;
594 spin_lock_irq(&hpet_task_lock);
595 spin_lock(&hpet_lock);
597 for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
598 for (timer = hpetp->hp_hpet->hpet_timers, i = 0;
599 i < hpetp->hp_ntimer; i++, timer++) {
600 if ((readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK)
604 devp = &hpetp->hp_dev[i];
606 if (devp->hd_flags & HPET_OPEN || devp->hd_task) {
611 tp->ht_opaque = devp;
616 spin_unlock(&hpet_lock);
617 spin_unlock_irq(&hpet_task_lock);
625 static inline int hpet_tpcheck(struct hpet_task *tp)
627 struct hpet_dev *devp;
630 devp = tp->ht_opaque;
635 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
636 if (devp >= hpetp->hp_dev
637 && devp < (hpetp->hp_dev + hpetp->hp_ntimer)
638 && devp->hd_hpet == hpetp->hp_hpet)
644 int hpet_unregister(struct hpet_task *tp)
646 struct hpet_dev *devp;
647 struct hpet_timer __iomem *timer;
650 if ((err = hpet_tpcheck(tp)))
653 spin_lock_irq(&hpet_task_lock);
654 spin_lock(&hpet_lock);
656 devp = tp->ht_opaque;
657 if (devp->hd_task != tp) {
658 spin_unlock(&hpet_lock);
659 spin_unlock_irq(&hpet_task_lock);
663 timer = devp->hd_timer;
664 writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
665 &timer->hpet_config);
666 devp->hd_flags &= ~(HPET_IE | HPET_PERIODIC);
667 devp->hd_task = NULL;
668 spin_unlock(&hpet_lock);
669 spin_unlock_irq(&hpet_task_lock);
674 int hpet_control(struct hpet_task *tp, unsigned int cmd, unsigned long arg)
676 struct hpet_dev *devp;
679 if ((err = hpet_tpcheck(tp)))
682 spin_lock_irq(&hpet_lock);
683 devp = tp->ht_opaque;
684 if (devp->hd_task != tp) {
685 spin_unlock_irq(&hpet_lock);
688 spin_unlock_irq(&hpet_lock);
689 return hpet_ioctl_common(devp, cmd, arg, 1);
692 static ctl_table hpet_table[] = {
695 .procname = "max-user-freq",
696 .data = &hpet_max_freq,
697 .maxlen = sizeof(int),
699 .proc_handler = &proc_dointvec,
704 static ctl_table hpet_root[] = {
715 static ctl_table dev_root[] = {
726 static struct ctl_table_header *sysctl_header;
728 static void hpet_register_interpolator(struct hpets *hpetp)
730 #ifdef CONFIG_TIME_INTERPOLATION
731 struct time_interpolator *ti;
733 ti = kmalloc(sizeof(*ti), GFP_KERNEL);
737 memset(ti, 0, sizeof(*ti));
738 ti->source = TIME_SOURCE_MMIO64;
740 ti->addr = &hpetp->hp_hpet->hpet_mc;
741 ti->frequency = hpetp->hp_tick_freq;
742 ti->drift = HPET_DRIFT;
745 hpetp->hp_interpolator = ti;
746 register_time_interpolator(ti);
751 * Adjustment for when arming the timer with
752 * initial conditions. That is, main counter
753 * ticks expired before interrupts are enabled.
755 #define TICK_CALIBRATE (1000UL)
757 static unsigned long hpet_calibrate(struct hpets *hpetp)
759 struct hpet_timer __iomem *timer = NULL;
760 unsigned long t, m, count, i, flags, start;
761 struct hpet_dev *devp;
763 struct hpet __iomem *hpet;
765 for (j = 0, devp = hpetp->hp_dev; j < hpetp->hp_ntimer; j++, devp++)
766 if ((devp->hd_flags & HPET_OPEN) == 0) {
767 timer = devp->hd_timer;
774 hpet = hpetp->hp_hpet;
775 t = read_counter(&timer->hpet_compare);
778 count = hpet_time_div(hpetp, TICK_CALIBRATE);
780 local_irq_save(flags);
782 start = read_counter(&hpet->hpet_mc);
785 m = read_counter(&hpet->hpet_mc);
786 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
787 } while (i++, (m - start) < count);
789 local_irq_restore(flags);
791 return (m - start) / i;
794 int hpet_alloc(struct hpet_data *hdp)
797 struct hpet_dev *devp;
801 struct hpet __iomem *hpet;
802 static struct hpets *last = (struct hpets *)0;
803 unsigned long period;
804 unsigned long long temp;
807 * hpet_alloc can be called by platform dependent code.
808 * if platform dependent code has allocated the hpet
809 * ACPI also reports hpet, then we catch it here.
811 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
812 if (hpetp->hp_hpet_phys == hdp->hd_phys_address) {
813 printk(KERN_DEBUG "%s: duplicate HPET ignored\n",
818 siz = sizeof(struct hpets) + ((hdp->hd_nirqs - 1) *
819 sizeof(struct hpet_dev));
821 hpetp = kmalloc(siz, GFP_KERNEL);
826 memset(hpetp, 0, siz);
828 hpetp->hp_which = hpet_nhpet++;
829 hpetp->hp_hpet = hdp->hd_address;
830 hpetp->hp_hpet_phys = hdp->hd_phys_address;
832 hpetp->hp_ntimer = hdp->hd_nirqs;
834 for (i = 0; i < hdp->hd_nirqs; i++)
835 hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i];
837 hpet = hpetp->hp_hpet;
839 cap = readq(&hpet->hpet_cap);
841 ntimer = ((cap & HPET_NUM_TIM_CAP_MASK) >> HPET_NUM_TIM_CAP_SHIFT) + 1;
843 if (hpetp->hp_ntimer != ntimer) {
844 printk(KERN_WARNING "hpet: number irqs doesn't agree"
845 " with number of timers\n");
851 last->hp_next = hpetp;
857 period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
858 HPET_COUNTER_CLK_PERIOD_SHIFT; /* fs, 10^-15 */
859 temp = 1000000000000000uLL; /* 10^15 femtoseconds per second */
860 temp += period >> 1; /* round */
861 do_div(temp, period);
862 hpetp->hp_tick_freq = temp; /* ticks per second */
864 printk(KERN_INFO "hpet%d: at MMIO 0x%lx (virtual 0x%p), IRQ%s",
865 hpetp->hp_which, hdp->hd_phys_address, hdp->hd_address,
866 hpetp->hp_ntimer > 1 ? "s" : "");
867 for (i = 0; i < hpetp->hp_ntimer; i++)
868 printk("%s %d", i > 0 ? "," : "", hdp->hd_irq[i]);
871 printk(KERN_INFO "hpet%u: %u %d-bit timers, %Lu Hz\n",
872 hpetp->hp_which, hpetp->hp_ntimer,
873 cap & HPET_COUNTER_SIZE_MASK ? 64 : 32, hpetp->hp_tick_freq);
875 mcfg = readq(&hpet->hpet_config);
876 if ((mcfg & HPET_ENABLE_CNF_MASK) == 0) {
877 write_counter(0L, &hpet->hpet_mc);
878 mcfg |= HPET_ENABLE_CNF_MASK;
879 writeq(mcfg, &hpet->hpet_config);
882 for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer; i++, devp++) {
883 struct hpet_timer __iomem *timer;
885 timer = &hpet->hpet_timers[devp - hpetp->hp_dev];
887 devp->hd_hpets = hpetp;
888 devp->hd_hpet = hpet;
889 devp->hd_timer = timer;
892 * If the timer was reserved by platform code,
893 * then make timer unavailable for opens.
895 if (hdp->hd_state & (1 << i)) {
896 devp->hd_flags = HPET_OPEN;
900 init_waitqueue_head(&devp->hd_waitqueue);
903 hpetp->hp_delta = hpet_calibrate(hpetp);
904 hpet_register_interpolator(hpetp);
909 static acpi_status hpet_resources(struct acpi_resource *res, void *data)
911 struct hpet_data *hdp;
913 struct acpi_resource_address64 addr;
918 status = acpi_resource_to_address64(res, &addr);
920 if (ACPI_SUCCESS(status)) {
923 size = addr.max_address_range - addr.min_address_range + 1;
924 hdp->hd_phys_address = addr.min_address_range;
925 hdp->hd_address = ioremap(addr.min_address_range, size);
927 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
928 if (hpetp->hp_hpet_phys == hdp->hd_phys_address) {
929 printk(KERN_DEBUG "%s: 0x%lx is busy\n",
930 __FUNCTION__, hdp->hd_phys_address);
931 iounmap(hdp->hd_address);
934 } else if (res->id == ACPI_RSTYPE_FIXED_MEM32) {
935 struct acpi_resource_fixed_mem32 *fixmem32;
937 fixmem32 = &res->data.fixed_memory32;
941 hdp->hd_phys_address = fixmem32->range_base_address;
942 hdp->hd_address = ioremap(fixmem32->range_base_address,
945 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
946 if (hpetp->hp_hpet_phys == hdp->hd_phys_address) {
947 printk(KERN_DEBUG "%s: 0x%lx is busy\n",
948 __FUNCTION__, hdp->hd_phys_address);
949 iounmap(hdp->hd_address);
952 } else if (res->id == ACPI_RSTYPE_EXT_IRQ) {
953 struct acpi_resource_ext_irq *irqp;
956 irqp = &res->data.extended_irq;
958 if (irqp->number_of_interrupts > 0) {
959 hdp->hd_nirqs = irqp->number_of_interrupts;
961 for (i = 0; i < hdp->hd_nirqs; i++) {
963 acpi_register_gsi(irqp->interrupts[i],
965 irqp->active_high_low);
976 static int hpet_acpi_add(struct acpi_device *device)
979 struct hpet_data data;
981 memset(&data, 0, sizeof(data));
984 acpi_walk_resources(device->handle, METHOD_NAME__CRS,
985 hpet_resources, &data);
987 if (ACPI_FAILURE(result))
990 if (!data.hd_address || !data.hd_nirqs) {
991 printk("%s: no address or irqs in _CRS\n", __FUNCTION__);
995 return hpet_alloc(&data);
998 static int hpet_acpi_remove(struct acpi_device *device, int type)
1000 /* XXX need to unregister interpolator, dealloc mem, etc */
1004 static struct acpi_driver hpet_acpi_driver = {
1008 .add = hpet_acpi_add,
1009 .remove = hpet_acpi_remove,
1013 static struct miscdevice hpet_misc = { HPET_MINOR, "hpet", &hpet_fops };
1015 static int __init hpet_init(void)
1019 result = misc_register(&hpet_misc);
1023 sysctl_header = register_sysctl_table(dev_root, 0);
1025 result = acpi_bus_register_driver(&hpet_acpi_driver);
1028 unregister_sysctl_table(sysctl_header);
1029 misc_deregister(&hpet_misc);
1036 static void __exit hpet_exit(void)
1038 acpi_bus_unregister_driver(&hpet_acpi_driver);
1041 unregister_sysctl_table(sysctl_header);
1042 misc_deregister(&hpet_misc);
1047 module_init(hpet_init);
1048 module_exit(hpet_exit);
1049 MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>");
1050 MODULE_LICENSE("GPL");