blob: 051474c65b783c5e9f3315de2fb3732516810027 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Intel & MS High Precision Event Timer Implementation.
3 *
4 * Copyright (C) 2003 Intel Corporation
5 * Venki Pallipadi
6 * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
7 * Bob Picco <robert.picco@hp.com>
8 *
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.
12 */
13
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/interrupt.h>
15#include <linux/module.h>
16#include <linux/kernel.h>
17#include <linux/types.h>
18#include <linux/miscdevice.h>
19#include <linux/major.h>
20#include <linux/ioport.h>
21#include <linux/fcntl.h>
22#include <linux/init.h>
23#include <linux/poll.h>
Al Virof23f6e02006-10-20 15:17:02 -040024#include <linux/mm.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070025#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>
Arnd Bergmann54066a52010-03-22 20:55:11 +010032#include <linux/compat.h>
Tony Luck0aa366f2007-07-20 11:22:30 -070033#include <linux/clocksource.h>
Jaswinder Singh Rajput0ca01762010-10-26 14:22:13 -070034#include <linux/uaccess.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090035#include <linux/slab.h>
Jaswinder Singh Rajput0ca01762010-10-26 14:22:13 -070036#include <linux/io.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
38#include <asm/current.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#include <asm/system.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#include <asm/irq.h>
41#include <asm/div64.h>
42
43#include <linux/acpi.h>
44#include <acpi/acpi_bus.h>
45#include <linux/hpet.h>
46
47/*
48 * The High Precision Event Timer driver.
49 * This driver is closely modelled after the rtc.c driver.
Denis V. Luneve45f2c02008-11-24 11:28:36 +030050 * http://www.intel.com/hardwaredesign/hpetspec_1.pdf
Linus Torvalds1da177e2005-04-16 15:20:36 -070051 */
52#define HPET_USER_FREQ (64)
53#define HPET_DRIFT (500)
54
Randy Dunlap757c4722005-10-30 15:03:42 -080055#define HPET_RANGE_SIZE 1024 /* from HPET spec */
56
David Brownell64a76f62008-07-29 12:47:38 -070057
58/* WARNING -- don't get confused. These macros are never used
59 * to write the (single) counter, and rarely to read it.
60 * They're badly named; to fix, someday.
61 */
Tony Luck0aa366f2007-07-20 11:22:30 -070062#if BITS_PER_LONG == 64
63#define write_counter(V, MC) writeq(V, MC)
64#define read_counter(MC) readq(MC)
65#else
66#define write_counter(V, MC) writel(V, MC)
67#define read_counter(MC) readl(MC)
68#endif
69
Arnd Bergmann54066a52010-03-22 20:55:11 +010070static DEFINE_MUTEX(hpet_mutex); /* replaces BKL */
Clemens Ladisch642d30b2005-10-30 15:03:31 -080071static u32 hpet_nhpet, hpet_max_freq = HPET_USER_FREQ;
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
S.Çağlar Onur3dffec42007-09-26 12:15:33 +030073/* This clocksource driver currently only works on ia64 */
74#ifdef CONFIG_IA64
Tony Luck0aa366f2007-07-20 11:22:30 -070075static void __iomem *hpet_mctr;
76
Magnus Damm8e196082009-04-21 12:24:00 -070077static cycle_t read_hpet(struct clocksource *cs)
Tony Luck0aa366f2007-07-20 11:22:30 -070078{
79 return (cycle_t)read_counter((void __iomem *)hpet_mctr);
80}
81
82static struct clocksource clocksource_hpet = {
Jaswinder Singh Rajput0ca01762010-10-26 14:22:13 -070083 .name = "hpet",
84 .rating = 250,
85 .read = read_hpet,
86 .mask = CLOCKSOURCE_MASK(64),
Jaswinder Singh Rajput0ca01762010-10-26 14:22:13 -070087 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
Tony Luck0aa366f2007-07-20 11:22:30 -070088};
89static struct clocksource *hpet_clocksource;
S.Çağlar Onur3dffec42007-09-26 12:15:33 +030090#endif
Tony Luck0aa366f2007-07-20 11:22:30 -070091
Linus Torvalds1da177e2005-04-16 15:20:36 -070092/* A lock for concurrent access by app and isr hpet activity. */
93static DEFINE_SPINLOCK(hpet_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070094
95#define HPET_DEV_NAME (7)
96
97struct hpet_dev {
98 struct hpets *hd_hpets;
99 struct hpet __iomem *hd_hpet;
100 struct hpet_timer __iomem *hd_timer;
101 unsigned long hd_ireqfreq;
102 unsigned long hd_irqdata;
103 wait_queue_head_t hd_waitqueue;
104 struct fasync_struct *hd_async_queue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105 unsigned int hd_flags;
106 unsigned int hd_irq;
107 unsigned int hd_hdwirq;
108 char hd_name[HPET_DEV_NAME];
109};
110
111struct hpets {
112 struct hpets *hp_next;
113 struct hpet __iomem *hp_hpet;
114 unsigned long hp_hpet_phys;
Tony Luck0aa366f2007-07-20 11:22:30 -0700115 struct clocksource *hp_clocksource;
Clemens Ladischba3f2132005-10-30 15:03:31 -0800116 unsigned long long hp_tick_freq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117 unsigned long hp_delta;
118 unsigned int hp_ntimer;
119 unsigned int hp_which;
120 struct hpet_dev hp_dev[1];
121};
122
123static struct hpets *hpets;
124
125#define HPET_OPEN 0x0001
126#define HPET_IE 0x0002 /* interrupt enabled */
127#define HPET_PERIODIC 0x0004
Clemens Ladisch0d290862005-10-30 15:03:34 -0800128#define HPET_SHARED_IRQ 0x0008
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130
131#ifndef readq
Adrian Bunk887c27f2005-09-10 00:26:52 -0700132static inline unsigned long long readq(void __iomem *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133{
134 return readl(addr) | (((unsigned long long)readl(addr + 4)) << 32LL);
135}
136#endif
137
138#ifndef writeq
Adrian Bunk887c27f2005-09-10 00:26:52 -0700139static inline void writeq(unsigned long long v, void __iomem *addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140{
141 writel(v & 0xffffffff, addr);
142 writel(v >> 32, addr + 4);
143}
144#endif
145
David Howells7d12e782006-10-05 14:55:46 +0100146static irqreturn_t hpet_interrupt(int irq, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700147{
148 struct hpet_dev *devp;
149 unsigned long isr;
150
151 devp = data;
Clemens Ladisch0d290862005-10-30 15:03:34 -0800152 isr = 1 << (devp - devp->hd_hpets->hp_dev);
153
154 if ((devp->hd_flags & HPET_SHARED_IRQ) &&
155 !(isr & readl(&devp->hd_hpet->hpet_isr)))
156 return IRQ_NONE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157
158 spin_lock(&hpet_lock);
159 devp->hd_irqdata++;
160
161 /*
162 * For non-periodic timers, increment the accumulator.
163 * This has the effect of treating non-periodic like periodic.
164 */
165 if ((devp->hd_flags & (HPET_IE | HPET_PERIODIC)) == HPET_IE) {
166 unsigned long m, t;
167
168 t = devp->hd_ireqfreq;
Nils Carlsonae21cf92009-09-23 15:57:13 -0700169 m = read_counter(&devp->hd_timer->hpet_compare);
170 write_counter(t + m, &devp->hd_timer->hpet_compare);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171 }
172
Clemens Ladisch0d290862005-10-30 15:03:34 -0800173 if (devp->hd_flags & HPET_SHARED_IRQ)
174 writel(isr, &devp->hd_hpet->hpet_isr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 spin_unlock(&hpet_lock);
176
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177 wake_up_interruptible(&devp->hd_waitqueue);
178
179 kill_fasync(&devp->hd_async_queue, SIGIO, POLL_IN);
180
181 return IRQ_HANDLED;
182}
183
Kevin Hao70ef6d52008-05-29 18:41:04 +0800184static void hpet_timer_set_irq(struct hpet_dev *devp)
185{
186 unsigned long v;
187 int irq, gsi;
188 struct hpet_timer __iomem *timer;
189
190 spin_lock_irq(&hpet_lock);
191 if (devp->hd_hdwirq) {
192 spin_unlock_irq(&hpet_lock);
193 return;
194 }
195
196 timer = devp->hd_timer;
197
198 /* we prefer level triggered mode */
199 v = readl(&timer->hpet_config);
200 if (!(v & Tn_INT_TYPE_CNF_MASK)) {
201 v |= Tn_INT_TYPE_CNF_MASK;
202 writel(v, &timer->hpet_config);
203 }
204 spin_unlock_irq(&hpet_lock);
205
206 v = (readq(&timer->hpet_config) & Tn_INT_ROUTE_CAP_MASK) >>
207 Tn_INT_ROUTE_CAP_SHIFT;
208
209 /*
210 * In PIC mode, skip IRQ0-4, IRQ6-9, IRQ12-15 which is always used by
211 * legacy device. In IO APIC mode, we skip all the legacy IRQS.
212 */
213 if (acpi_irq_model == ACPI_IRQ_MODEL_PIC)
214 v &= ~0xf3df;
215 else
216 v &= ~0xffff;
217
Akinobu Mitae5d61512010-03-15 00:35:01 -0400218 for_each_set_bit(irq, &v, HPET_MAX_IRQ) {
Yinghai Lu1f45f562008-08-19 20:49:49 -0700219 if (irq >= nr_irqs) {
Kevin Hao70ef6d52008-05-29 18:41:04 +0800220 irq = HPET_MAX_IRQ;
221 break;
222 }
223
Yinghai Lua2f809b2009-04-27 18:01:20 -0700224 gsi = acpi_register_gsi(NULL, irq, ACPI_LEVEL_SENSITIVE,
Kevin Hao70ef6d52008-05-29 18:41:04 +0800225 ACPI_ACTIVE_LOW);
226 if (gsi > 0)
227 break;
228
229 /* FIXME: Setup interrupt source table */
230 }
231
232 if (irq < HPET_MAX_IRQ) {
233 spin_lock_irq(&hpet_lock);
234 v = readl(&timer->hpet_config);
235 v |= irq << Tn_INT_ROUTE_CNF_SHIFT;
236 writel(v, &timer->hpet_config);
237 devp->hd_hdwirq = gsi;
238 spin_unlock_irq(&hpet_lock);
239 }
240 return;
241}
242
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243static int hpet_open(struct inode *inode, struct file *file)
244{
245 struct hpet_dev *devp;
246 struct hpets *hpetp;
247 int i;
248
249 if (file->f_mode & FMODE_WRITE)
250 return -EINVAL;
251
Arnd Bergmann54066a52010-03-22 20:55:11 +0100252 mutex_lock(&hpet_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 spin_lock_irq(&hpet_lock);
254
255 for (devp = NULL, hpetp = hpets; hpetp && !devp; hpetp = hpetp->hp_next)
256 for (i = 0; i < hpetp->hp_ntimer; i++)
David Brownell64a76f62008-07-29 12:47:38 -0700257 if (hpetp->hp_dev[i].hd_flags & HPET_OPEN)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 continue;
259 else {
260 devp = &hpetp->hp_dev[i];
261 break;
262 }
263
264 if (!devp) {
265 spin_unlock_irq(&hpet_lock);
Arnd Bergmann54066a52010-03-22 20:55:11 +0100266 mutex_unlock(&hpet_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267 return -EBUSY;
268 }
269
270 file->private_data = devp;
271 devp->hd_irqdata = 0;
272 devp->hd_flags |= HPET_OPEN;
273 spin_unlock_irq(&hpet_lock);
Arnd Bergmann54066a52010-03-22 20:55:11 +0100274 mutex_unlock(&hpet_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275
Kevin Hao70ef6d52008-05-29 18:41:04 +0800276 hpet_timer_set_irq(devp);
277
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278 return 0;
279}
280
281static ssize_t
282hpet_read(struct file *file, char __user *buf, size_t count, loff_t * ppos)
283{
284 DECLARE_WAITQUEUE(wait, current);
285 unsigned long data;
286 ssize_t retval;
287 struct hpet_dev *devp;
288
289 devp = file->private_data;
290 if (!devp->hd_ireqfreq)
291 return -EIO;
292
293 if (count < sizeof(unsigned long))
294 return -EINVAL;
295
296 add_wait_queue(&devp->hd_waitqueue, &wait);
297
298 for ( ; ; ) {
299 set_current_state(TASK_INTERRUPTIBLE);
300
301 spin_lock_irq(&hpet_lock);
302 data = devp->hd_irqdata;
303 devp->hd_irqdata = 0;
304 spin_unlock_irq(&hpet_lock);
305
306 if (data)
307 break;
308 else if (file->f_flags & O_NONBLOCK) {
309 retval = -EAGAIN;
310 goto out;
311 } else if (signal_pending(current)) {
312 retval = -ERESTARTSYS;
313 goto out;
314 }
315 schedule();
316 }
317
318 retval = put_user(data, (unsigned long __user *)buf);
319 if (!retval)
320 retval = sizeof(unsigned long);
321out:
322 __set_current_state(TASK_RUNNING);
323 remove_wait_queue(&devp->hd_waitqueue, &wait);
324
325 return retval;
326}
327
328static unsigned int hpet_poll(struct file *file, poll_table * wait)
329{
330 unsigned long v;
331 struct hpet_dev *devp;
332
333 devp = file->private_data;
334
335 if (!devp->hd_ireqfreq)
336 return 0;
337
338 poll_wait(file, &devp->hd_waitqueue, wait);
339
340 spin_lock_irq(&hpet_lock);
341 v = devp->hd_irqdata;
342 spin_unlock_irq(&hpet_lock);
343
344 if (v != 0)
345 return POLLIN | POLLRDNORM;
346
347 return 0;
348}
349
350static int hpet_mmap(struct file *file, struct vm_area_struct *vma)
351{
352#ifdef CONFIG_HPET_MMAP
353 struct hpet_dev *devp;
354 unsigned long addr;
355
356 if (((vma->vm_end - vma->vm_start) != PAGE_SIZE) || vma->vm_pgoff)
357 return -EINVAL;
358
359 devp = file->private_data;
360 addr = devp->hd_hpets->hp_hpet_phys;
361
362 if (addr & (PAGE_SIZE - 1))
363 return -ENOSYS;
364
365 vma->vm_flags |= VM_IO;
366 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367
368 if (io_remap_pfn_range(vma, vma->vm_start, addr >> PAGE_SHIFT,
369 PAGE_SIZE, vma->vm_page_prot)) {
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800370 printk(KERN_ERR "%s: io_remap_pfn_range failed\n",
Harvey Harrisonbf9d8922008-04-30 00:55:10 -0700371 __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700372 return -EAGAIN;
373 }
374
375 return 0;
376#else
377 return -ENOSYS;
378#endif
379}
380
381static int hpet_fasync(int fd, struct file *file, int on)
382{
383 struct hpet_dev *devp;
384
385 devp = file->private_data;
386
387 if (fasync_helper(fd, file, on, &devp->hd_async_queue) >= 0)
388 return 0;
389 else
390 return -EIO;
391}
392
393static int hpet_release(struct inode *inode, struct file *file)
394{
395 struct hpet_dev *devp;
396 struct hpet_timer __iomem *timer;
397 int irq = 0;
398
399 devp = file->private_data;
400 timer = devp->hd_timer;
401
402 spin_lock_irq(&hpet_lock);
403
404 writeq((readq(&timer->hpet_config) & ~Tn_INT_ENB_CNF_MASK),
405 &timer->hpet_config);
406
407 irq = devp->hd_irq;
408 devp->hd_irq = 0;
409
410 devp->hd_ireqfreq = 0;
411
412 if (devp->hd_flags & HPET_PERIODIC
413 && readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
414 unsigned long v;
415
416 v = readq(&timer->hpet_config);
417 v ^= Tn_TYPE_CNF_MASK;
418 writeq(v, &timer->hpet_config);
419 }
420
421 devp->hd_flags &= ~(HPET_OPEN | HPET_IE | HPET_PERIODIC);
422 spin_unlock_irq(&hpet_lock);
423
424 if (irq)
425 free_irq(irq, devp);
426
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427 file->private_data = NULL;
428 return 0;
429}
430
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431static int hpet_ioctl_ieon(struct hpet_dev *devp)
432{
433 struct hpet_timer __iomem *timer;
434 struct hpet __iomem *hpet;
435 struct hpets *hpetp;
436 int irq;
437 unsigned long g, v, t, m;
438 unsigned long flags, isr;
439
440 timer = devp->hd_timer;
441 hpet = devp->hd_hpet;
442 hpetp = devp->hd_hpets;
443
Clemens Ladisch9090e6d2005-10-30 15:03:29 -0800444 if (!devp->hd_ireqfreq)
445 return -EIO;
446
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447 spin_lock_irq(&hpet_lock);
448
449 if (devp->hd_flags & HPET_IE) {
450 spin_unlock_irq(&hpet_lock);
451 return -EBUSY;
452 }
453
454 devp->hd_flags |= HPET_IE;
Clemens Ladisch0d290862005-10-30 15:03:34 -0800455
456 if (readl(&timer->hpet_config) & Tn_INT_TYPE_CNF_MASK)
457 devp->hd_flags |= HPET_SHARED_IRQ;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 spin_unlock_irq(&hpet_lock);
459
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 irq = devp->hd_hdwirq;
461
462 if (irq) {
Clemens Ladisch0d290862005-10-30 15:03:34 -0800463 unsigned long irq_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464
Clemens Ladisch96e96942010-10-26 14:22:13 -0700465 if (devp->hd_flags & HPET_SHARED_IRQ) {
466 /*
467 * To prevent the interrupt handler from seeing an
468 * unwanted interrupt status bit, program the timer
469 * so that it will not fire in the near future ...
470 */
471 writel(readl(&timer->hpet_config) & ~Tn_TYPE_CNF_MASK,
472 &timer->hpet_config);
473 write_counter(read_counter(&hpet->hpet_mc),
474 &timer->hpet_compare);
475 /* ... and clear any left-over status. */
476 isr = 1 << (devp - devp->hd_hpets->hp_dev);
477 writel(isr, &hpet->hpet_isr);
478 }
479
Clemens Ladisch0d290862005-10-30 15:03:34 -0800480 sprintf(devp->hd_name, "hpet%d", (int)(devp - hpetp->hp_dev));
481 irq_flags = devp->hd_flags & HPET_SHARED_IRQ
Thomas Gleixner0f2ed4c2006-07-01 19:29:33 -0700482 ? IRQF_SHARED : IRQF_DISABLED;
Clemens Ladisch0d290862005-10-30 15:03:34 -0800483 if (request_irq(irq, hpet_interrupt, irq_flags,
484 devp->hd_name, (void *)devp)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485 printk(KERN_ERR "hpet: IRQ %d is not free\n", irq);
486 irq = 0;
487 }
488 }
489
490 if (irq == 0) {
491 spin_lock_irq(&hpet_lock);
492 devp->hd_flags ^= HPET_IE;
493 spin_unlock_irq(&hpet_lock);
494 return -EIO;
495 }
496
497 devp->hd_irq = irq;
498 t = devp->hd_ireqfreq;
499 v = readq(&timer->hpet_config);
David Brownell64a76f62008-07-29 12:47:38 -0700500
501 /* 64-bit comparators are not yet supported through the ioctls,
502 * so force this into 32-bit mode if it supports both modes
503 */
504 g = v | Tn_32MODE_CNF_MASK | Tn_INT_ENB_CNF_MASK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505
506 if (devp->hd_flags & HPET_PERIODIC) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700507 g |= Tn_TYPE_CNF_MASK;
Nils Carlsonae21cf92009-09-23 15:57:13 -0700508 v |= Tn_TYPE_CNF_MASK | Tn_VAL_SET_CNF_MASK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509 writeq(v, &timer->hpet_config);
510 local_irq_save(flags);
David Brownell64a76f62008-07-29 12:47:38 -0700511
Nils Carlsonae21cf92009-09-23 15:57:13 -0700512 /*
513 * NOTE: First we modify the hidden accumulator
David Brownell64a76f62008-07-29 12:47:38 -0700514 * register supported by periodic-capable comparators.
515 * We never want to modify the (single) counter; that
Nils Carlsonae21cf92009-09-23 15:57:13 -0700516 * would affect all the comparators. The value written
517 * is the counter value when the first interrupt is due.
David Brownell64a76f62008-07-29 12:47:38 -0700518 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519 m = read_counter(&hpet->hpet_mc);
520 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
Nils Carlsonae21cf92009-09-23 15:57:13 -0700521 /*
522 * Then we modify the comparator, indicating the period
523 * for subsequent interrupt.
524 */
525 write_counter(t, &timer->hpet_compare);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 } else {
527 local_irq_save(flags);
528 m = read_counter(&hpet->hpet_mc);
529 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
530 }
531
Clemens Ladisch0d290862005-10-30 15:03:34 -0800532 if (devp->hd_flags & HPET_SHARED_IRQ) {
Clemens Ladisch3d5640d2005-10-30 15:03:39 -0800533 isr = 1 << (devp - devp->hd_hpets->hp_dev);
Clemens Ladisch0d290862005-10-30 15:03:34 -0800534 writel(isr, &hpet->hpet_isr);
535 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 writeq(g, &timer->hpet_config);
537 local_irq_restore(flags);
538
539 return 0;
540}
541
Clemens Ladischba3f2132005-10-30 15:03:31 -0800542/* converts Hz to number of timer ticks */
543static inline unsigned long hpet_time_div(struct hpets *hpets,
544 unsigned long dis)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545{
Clemens Ladischba3f2132005-10-30 15:03:31 -0800546 unsigned long long m;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547
Clemens Ladischba3f2132005-10-30 15:03:31 -0800548 m = hpets->hp_tick_freq + (dis >> 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549 do_div(m, dis);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550 return (unsigned long)m;
551}
552
553static int
Arnd Bergmann54066a52010-03-22 20:55:11 +0100554hpet_ioctl_common(struct hpet_dev *devp, int cmd, unsigned long arg,
555 struct hpet_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556{
557 struct hpet_timer __iomem *timer;
558 struct hpet __iomem *hpet;
559 struct hpets *hpetp;
560 int err;
561 unsigned long v;
562
563 switch (cmd) {
564 case HPET_IE_OFF:
565 case HPET_INFO:
566 case HPET_EPI:
567 case HPET_DPI:
568 case HPET_IRQFREQ:
569 timer = devp->hd_timer;
570 hpet = devp->hd_hpet;
571 hpetp = devp->hd_hpets;
572 break;
573 case HPET_IE_ON:
574 return hpet_ioctl_ieon(devp);
575 default:
576 return -EINVAL;
577 }
578
579 err = 0;
580
581 switch (cmd) {
582 case HPET_IE_OFF:
583 if ((devp->hd_flags & HPET_IE) == 0)
584 break;
585 v = readq(&timer->hpet_config);
586 v &= ~Tn_INT_ENB_CNF_MASK;
587 writeq(v, &timer->hpet_config);
588 if (devp->hd_irq) {
589 free_irq(devp->hd_irq, devp);
590 devp->hd_irq = 0;
591 }
592 devp->hd_flags ^= HPET_IE;
593 break;
594 case HPET_INFO:
595 {
Vasiliy Kulikovdae512e2010-10-26 14:22:15 -0700596 memset(info, 0, sizeof(*info));
Clemens Ladischaf95ead2005-10-30 15:03:38 -0800597 if (devp->hd_ireqfreq)
Arnd Bergmann54066a52010-03-22 20:55:11 +0100598 info->hi_ireqfreq =
Clemens Ladischaf95ead2005-10-30 15:03:38 -0800599 hpet_time_div(hpetp, devp->hd_ireqfreq);
Arnd Bergmann54066a52010-03-22 20:55:11 +0100600 info->hi_flags =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 readq(&timer->hpet_config) & Tn_PER_INT_CAP_MASK;
Arnd Bergmann54066a52010-03-22 20:55:11 +0100602 info->hi_hpet = hpetp->hp_which;
603 info->hi_timer = devp - hpetp->hp_dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604 break;
605 }
606 case HPET_EPI:
607 v = readq(&timer->hpet_config);
608 if ((v & Tn_PER_INT_CAP_MASK) == 0) {
609 err = -ENXIO;
610 break;
611 }
612 devp->hd_flags |= HPET_PERIODIC;
613 break;
614 case HPET_DPI:
615 v = readq(&timer->hpet_config);
616 if ((v & Tn_PER_INT_CAP_MASK) == 0) {
617 err = -ENXIO;
618 break;
619 }
620 if (devp->hd_flags & HPET_PERIODIC &&
621 readq(&timer->hpet_config) & Tn_TYPE_CNF_MASK) {
622 v = readq(&timer->hpet_config);
623 v ^= Tn_TYPE_CNF_MASK;
624 writeq(v, &timer->hpet_config);
625 }
626 devp->hd_flags &= ~HPET_PERIODIC;
627 break;
628 case HPET_IRQFREQ:
Arnd Bergmann54066a52010-03-22 20:55:11 +0100629 if ((arg > hpet_max_freq) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 !capable(CAP_SYS_RESOURCE)) {
631 err = -EACCES;
632 break;
633 }
634
Clemens Ladisch189e2dd2005-10-30 15:03:33 -0800635 if (!arg) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636 err = -EINVAL;
637 break;
638 }
639
Clemens Ladischba3f2132005-10-30 15:03:31 -0800640 devp->hd_ireqfreq = hpet_time_div(hpetp, arg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 }
642
643 return err;
644}
645
Arnd Bergmann54066a52010-03-22 20:55:11 +0100646static long
647hpet_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
648{
649 struct hpet_info info;
650 int err;
651
652 mutex_lock(&hpet_mutex);
653 err = hpet_ioctl_common(file->private_data, cmd, arg, &info);
654 mutex_unlock(&hpet_mutex);
655
656 if ((cmd == HPET_INFO) && !err &&
657 (copy_to_user((void __user *)arg, &info, sizeof(info))))
658 err = -EFAULT;
659
660 return err;
661}
662
663#ifdef CONFIG_COMPAT
664struct compat_hpet_info {
665 compat_ulong_t hi_ireqfreq; /* Hz */
666 compat_ulong_t hi_flags; /* information */
667 unsigned short hi_hpet;
668 unsigned short hi_timer;
669};
670
671static long
672hpet_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
673{
674 struct hpet_info info;
675 int err;
676
677 mutex_lock(&hpet_mutex);
678 err = hpet_ioctl_common(file->private_data, cmd, arg, &info);
679 mutex_unlock(&hpet_mutex);
680
681 if ((cmd == HPET_INFO) && !err) {
682 struct compat_hpet_info __user *u = compat_ptr(arg);
683 if (put_user(info.hi_ireqfreq, &u->hi_ireqfreq) ||
684 put_user(info.hi_flags, &u->hi_flags) ||
685 put_user(info.hi_hpet, &u->hi_hpet) ||
686 put_user(info.hi_timer, &u->hi_timer))
687 err = -EFAULT;
688 }
689
690 return err;
691}
692#endif
693
Arjan van de Ven62322d22006-07-03 00:24:21 -0700694static const struct file_operations hpet_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700695 .owner = THIS_MODULE,
696 .llseek = no_llseek,
697 .read = hpet_read,
698 .poll = hpet_poll,
Arnd Bergmann55929332010-04-27 00:24:05 +0200699 .unlocked_ioctl = hpet_ioctl,
Arnd Bergmann54066a52010-03-22 20:55:11 +0100700#ifdef CONFIG_COMPAT
701 .compat_ioctl = hpet_compat_ioctl,
702#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 .open = hpet_open,
704 .release = hpet_release,
705 .fasync = hpet_fasync,
706 .mmap = hpet_mmap,
707};
708
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800709static int hpet_is_known(struct hpet_data *hdp)
710{
711 struct hpets *hpetp;
712
713 for (hpetp = hpets; hpetp; hpetp = hpetp->hp_next)
714 if (hpetp->hp_hpet_phys == hdp->hd_phys_address)
715 return 1;
716
717 return 0;
718}
719
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720static ctl_table hpet_table[] = {
721 {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722 .procname = "max-user-freq",
723 .data = &hpet_max_freq,
724 .maxlen = sizeof(int),
725 .mode = 0644,
Eric W. Biederman6d456112009-11-16 03:11:48 -0800726 .proc_handler = proc_dointvec,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727 },
Eric W. Biederman894d2492009-11-05 14:34:02 -0800728 {}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729};
730
731static ctl_table hpet_root[] = {
732 {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733 .procname = "hpet",
734 .maxlen = 0,
735 .mode = 0555,
736 .child = hpet_table,
737 },
Eric W. Biederman894d2492009-11-05 14:34:02 -0800738 {}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739};
740
741static ctl_table dev_root[] = {
742 {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743 .procname = "dev",
744 .maxlen = 0,
745 .mode = 0555,
746 .child = hpet_root,
747 },
Eric W. Biederman894d2492009-11-05 14:34:02 -0800748 {}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749};
750
751static struct ctl_table_header *sysctl_header;
752
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753/*
754 * Adjustment for when arming the timer with
755 * initial conditions. That is, main counter
756 * ticks expired before interrupts are enabled.
757 */
758#define TICK_CALIBRATE (1000UL)
759
Yasunori Goto303d3792009-04-02 16:58:31 -0700760static unsigned long __hpet_calibrate(struct hpets *hpetp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761{
762 struct hpet_timer __iomem *timer = NULL;
763 unsigned long t, m, count, i, flags, start;
764 struct hpet_dev *devp;
765 int j;
766 struct hpet __iomem *hpet;
767
768 for (j = 0, devp = hpetp->hp_dev; j < hpetp->hp_ntimer; j++, devp++)
769 if ((devp->hd_flags & HPET_OPEN) == 0) {
770 timer = devp->hd_timer;
771 break;
772 }
773
774 if (!timer)
775 return 0;
776
Clemens Ladisch3d5640d2005-10-30 15:03:39 -0800777 hpet = hpetp->hp_hpet;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700778 t = read_counter(&timer->hpet_compare);
779
780 i = 0;
Clemens Ladischba3f2132005-10-30 15:03:31 -0800781 count = hpet_time_div(hpetp, TICK_CALIBRATE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700782
783 local_irq_save(flags);
784
785 start = read_counter(&hpet->hpet_mc);
786
787 do {
788 m = read_counter(&hpet->hpet_mc);
789 write_counter(t + m + hpetp->hp_delta, &timer->hpet_compare);
790 } while (i++, (m - start) < count);
791
792 local_irq_restore(flags);
793
794 return (m - start) / i;
795}
796
Yasunori Goto303d3792009-04-02 16:58:31 -0700797static unsigned long hpet_calibrate(struct hpets *hpetp)
798{
799 unsigned long ret = -1;
800 unsigned long tmp;
801
802 /*
803 * Try to calibrate until return value becomes stable small value.
804 * If SMI interruption occurs in calibration loop, the return value
805 * will be big. This avoids its impact.
806 */
807 for ( ; ; ) {
808 tmp = __hpet_calibrate(hpetp);
809 if (ret <= tmp)
810 break;
811 ret = tmp;
812 }
813
814 return ret;
815}
816
Linus Torvalds1da177e2005-04-16 15:20:36 -0700817int hpet_alloc(struct hpet_data *hdp)
818{
Thomas Gleixner5761d642008-04-04 16:26:10 +0200819 u64 cap, mcfg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820 struct hpet_dev *devp;
Thomas Gleixner5761d642008-04-04 16:26:10 +0200821 u32 i, ntimer;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822 struct hpets *hpetp;
823 size_t siz;
824 struct hpet __iomem *hpet;
Jaswinder Singh Rajput0ca01762010-10-26 14:22:13 -0700825 static struct hpets *last;
Thomas Gleixner5761d642008-04-04 16:26:10 +0200826 unsigned long period;
Clemens Ladischba3f2132005-10-30 15:03:31 -0800827 unsigned long long temp;
David Brownellf92a7892008-07-31 12:59:56 -0700828 u32 remainder;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829
830 /*
831 * hpet_alloc can be called by platform dependent code.
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800832 * If platform dependent code has allocated the hpet that
833 * ACPI has also reported, then we catch it here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 */
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800835 if (hpet_is_known(hdp)) {
836 printk(KERN_DEBUG "%s: duplicate HPET ignored\n",
Harvey Harrisonbf9d8922008-04-30 00:55:10 -0700837 __func__);
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800838 return 0;
839 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840
841 siz = sizeof(struct hpets) + ((hdp->hd_nirqs - 1) *
842 sizeof(struct hpet_dev));
843
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800844 hpetp = kzalloc(siz, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845
846 if (!hpetp)
847 return -ENOMEM;
848
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849 hpetp->hp_which = hpet_nhpet++;
850 hpetp->hp_hpet = hdp->hd_address;
851 hpetp->hp_hpet_phys = hdp->hd_phys_address;
852
853 hpetp->hp_ntimer = hdp->hd_nirqs;
Thomas Gleixner5761d642008-04-04 16:26:10 +0200854
855 for (i = 0; i < hdp->hd_nirqs; i++)
856 hpetp->hp_dev[i].hd_hdwirq = hdp->hd_irq[i];
857
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858 hpet = hpetp->hp_hpet;
859
860 cap = readq(&hpet->hpet_cap);
861
862 ntimer = ((cap & HPET_NUM_TIM_CAP_MASK) >> HPET_NUM_TIM_CAP_SHIFT) + 1;
863
864 if (hpetp->hp_ntimer != ntimer) {
865 printk(KERN_WARNING "hpet: number irqs doesn't agree"
866 " with number of timers\n");
867 kfree(hpetp);
868 return -ENODEV;
869 }
870
871 if (last)
872 last->hp_next = hpetp;
873 else
874 hpets = hpetp;
875
876 last = hpetp;
877
Clemens Ladischba3f2132005-10-30 15:03:31 -0800878 period = (cap & HPET_COUNTER_CLK_PERIOD_MASK) >>
879 HPET_COUNTER_CLK_PERIOD_SHIFT; /* fs, 10^-15 */
880 temp = 1000000000000000uLL; /* 10^15 femtoseconds per second */
881 temp += period >> 1; /* round */
882 do_div(temp, period);
883 hpetp->hp_tick_freq = temp; /* ticks per second */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884
Andi Kleen3034d112006-09-26 10:52:28 +0200885 printk(KERN_INFO "hpet%d: at MMIO 0x%lx, IRQ%s",
886 hpetp->hp_which, hdp->hd_phys_address,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700887 hpetp->hp_ntimer > 1 ? "s" : "");
888 for (i = 0; i < hpetp->hp_ntimer; i++)
Thomas Gleixner5761d642008-04-04 16:26:10 +0200889 printk("%s %d", i > 0 ? "," : "", hdp->hd_irq[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700890 printk("\n");
891
David Brownellf92a7892008-07-31 12:59:56 -0700892 temp = hpetp->hp_tick_freq;
893 remainder = do_div(temp, 1000000);
David Brownell64a76f62008-07-29 12:47:38 -0700894 printk(KERN_INFO
895 "hpet%u: %u comparators, %d-bit %u.%06u MHz counter\n",
896 hpetp->hp_which, hpetp->hp_ntimer,
897 cap & HPET_COUNTER_SIZE_MASK ? 64 : 32,
David Brownellf92a7892008-07-31 12:59:56 -0700898 (unsigned) temp, remainder);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700899
900 mcfg = readq(&hpet->hpet_config);
901 if ((mcfg & HPET_ENABLE_CNF_MASK) == 0) {
902 write_counter(0L, &hpet->hpet_mc);
903 mcfg |= HPET_ENABLE_CNF_MASK;
904 writeq(mcfg, &hpet->hpet_config);
905 }
906
Clemens Ladisch642d30b2005-10-30 15:03:31 -0800907 for (i = 0, devp = hpetp->hp_dev; i < hpetp->hp_ntimer; i++, devp++) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908 struct hpet_timer __iomem *timer;
909
910 timer = &hpet->hpet_timers[devp - hpetp->hp_dev];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700911
912 devp->hd_hpets = hpetp;
913 devp->hd_hpet = hpet;
914 devp->hd_timer = timer;
915
916 /*
917 * If the timer was reserved by platform code,
918 * then make timer unavailable for opens.
919 */
920 if (hdp->hd_state & (1 << i)) {
921 devp->hd_flags = HPET_OPEN;
922 continue;
923 }
924
925 init_waitqueue_head(&devp->hd_waitqueue);
926 }
927
928 hpetp->hp_delta = hpet_calibrate(hpetp);
Tony Luck0aa366f2007-07-20 11:22:30 -0700929
Linus Torvalds3b2b64f2007-08-31 20:13:57 -0700930/* This clocksource driver currently only works on ia64 */
931#ifdef CONFIG_IA64
Tony Luck0aa366f2007-07-20 11:22:30 -0700932 if (!hpet_clocksource) {
933 hpet_mctr = (void __iomem *)&hpetp->hp_hpet->hpet_mc;
934 CLKSRC_FSYS_MMIO_SET(clocksource_hpet.fsys_mmio, hpet_mctr);
John Stultzd60c3042010-04-26 20:20:47 -0700935 clocksource_register_hz(&clocksource_hpet, hpetp->hp_tick_freq);
Tony Luck0aa366f2007-07-20 11:22:30 -0700936 hpetp->hp_clocksource = &clocksource_hpet;
937 hpet_clocksource = &clocksource_hpet;
938 }
Linus Torvalds3b2b64f2007-08-31 20:13:57 -0700939#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700940
941 return 0;
942}
943
944static acpi_status hpet_resources(struct acpi_resource *res, void *data)
945{
946 struct hpet_data *hdp;
947 acpi_status status;
948 struct acpi_resource_address64 addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949
950 hdp = data;
951
952 status = acpi_resource_to_address64(res, &addr);
953
954 if (ACPI_SUCCESS(status)) {
Bob Moore50eca3e2005-09-30 19:03:00 -0400955 hdp->hd_phys_address = addr.minimum;
Bjorn Helgaas9224a862006-03-28 17:04:00 -0500956 hdp->hd_address = ioremap(addr.minimum, addr.address_length);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700957
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800958 if (hpet_is_known(hdp)) {
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800959 iounmap(hdp->hd_address);
Zhao Yakui78e1ca42007-09-20 21:23:13 -0400960 return AE_ALREADY_EXISTS;
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800961 }
Bob Moore50eca3e2005-09-30 19:03:00 -0400962 } else if (res->type == ACPI_RESOURCE_TYPE_FIXED_MEMORY32) {
963 struct acpi_resource_fixed_memory32 *fixmem32;
Randy Dunlap757c4722005-10-30 15:03:42 -0800964
965 fixmem32 = &res->data.fixed_memory32;
966 if (!fixmem32)
Zhao Yakui78e1ca42007-09-20 21:23:13 -0400967 return AE_NO_MEMORY;
Randy Dunlap757c4722005-10-30 15:03:42 -0800968
Bob Moore50eca3e2005-09-30 19:03:00 -0400969 hdp->hd_phys_address = fixmem32->address;
970 hdp->hd_address = ioremap(fixmem32->address,
Randy Dunlap757c4722005-10-30 15:03:42 -0800971 HPET_RANGE_SIZE);
972
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800973 if (hpet_is_known(hdp)) {
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800974 iounmap(hdp->hd_address);
Zhao Yakui78e1ca42007-09-20 21:23:13 -0400975 return AE_ALREADY_EXISTS;
Randy Dunlap3e6716e2005-10-30 15:03:44 -0800976 }
Bob Moore50eca3e2005-09-30 19:03:00 -0400977 } else if (res->type == ACPI_RESOURCE_TYPE_EXTENDED_IRQ) {
978 struct acpi_resource_extended_irq *irqp;
Bjorn Helgaasbe5efff2006-02-14 13:53:02 -0800979 int i, irq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980
981 irqp = &res->data.extended_irq;
982
Bjorn Helgaasbe5efff2006-02-14 13:53:02 -0800983 for (i = 0; i < irqp->interrupt_count; i++) {
Yinghai Lua2f809b2009-04-27 18:01:20 -0700984 irq = acpi_register_gsi(NULL, irqp->interrupts[i],
Bjorn Helgaasbe5efff2006-02-14 13:53:02 -0800985 irqp->triggering, irqp->polarity);
986 if (irq < 0)
987 return AE_ERROR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700988
Bjorn Helgaasbe5efff2006-02-14 13:53:02 -0800989 hdp->hd_irq[hdp->hd_nirqs] = irq;
990 hdp->hd_nirqs++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991 }
992 }
993
994 return AE_OK;
995}
996
997static int hpet_acpi_add(struct acpi_device *device)
998{
999 acpi_status result;
1000 struct hpet_data data;
1001
1002 memset(&data, 0, sizeof(data));
1003
1004 result =
1005 acpi_walk_resources(device->handle, METHOD_NAME__CRS,
1006 hpet_resources, &data);
1007
1008 if (ACPI_FAILURE(result))
1009 return -ENODEV;
1010
1011 if (!data.hd_address || !data.hd_nirqs) {
Jiri Slabya56d5312010-10-26 14:22:11 -07001012 if (data.hd_address)
1013 iounmap(data.hd_address);
Harvey Harrisonbf9d8922008-04-30 00:55:10 -07001014 printk("%s: no address or irqs in _CRS\n", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015 return -ENODEV;
1016 }
1017
1018 return hpet_alloc(&data);
1019}
1020
1021static int hpet_acpi_remove(struct acpi_device *device, int type)
1022{
Tony Luck0aa366f2007-07-20 11:22:30 -07001023 /* XXX need to unregister clocksource, dealloc mem, etc */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001024 return -EINVAL;
1025}
1026
Thomas Renninger1ba90e32007-07-23 14:44:41 +02001027static const struct acpi_device_id hpet_device_ids[] = {
1028 {"PNP0103", 0},
1029 {"", 0},
1030};
1031MODULE_DEVICE_TABLE(acpi, hpet_device_ids);
1032
Linus Torvalds1da177e2005-04-16 15:20:36 -07001033static struct acpi_driver hpet_acpi_driver = {
1034 .name = "hpet",
Thomas Renninger1ba90e32007-07-23 14:44:41 +02001035 .ids = hpet_device_ids,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001036 .ops = {
1037 .add = hpet_acpi_add,
1038 .remove = hpet_acpi_remove,
1039 },
1040};
1041
1042static struct miscdevice hpet_misc = { HPET_MINOR, "hpet", &hpet_fops };
1043
1044static int __init hpet_init(void)
1045{
1046 int result;
1047
1048 result = misc_register(&hpet_misc);
1049 if (result < 0)
1050 return -ENODEV;
1051
Eric W. Biederman0b4d4142007-02-14 00:34:09 -08001052 sysctl_header = register_sysctl_table(dev_root);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053
1054 result = acpi_bus_register_driver(&hpet_acpi_driver);
1055 if (result < 0) {
1056 if (sysctl_header)
1057 unregister_sysctl_table(sysctl_header);
1058 misc_deregister(&hpet_misc);
1059 return result;
1060 }
1061
1062 return 0;
1063}
1064
1065static void __exit hpet_exit(void)
1066{
1067 acpi_bus_unregister_driver(&hpet_acpi_driver);
1068
1069 if (sysctl_header)
1070 unregister_sysctl_table(sysctl_header);
1071 misc_deregister(&hpet_misc);
1072
1073 return;
1074}
1075
1076module_init(hpet_init);
1077module_exit(hpet_exit);
1078MODULE_AUTHOR("Bob Picco <Robert.Picco@hp.com>");
1079MODULE_LICENSE("GPL");