2 * Driver for NEC VR4100 series Real Time Clock unit.
4 * Copyright (C) 2003-2005 Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 #include <linux/platform_device.h>
22 #include <linux/init.h>
23 #include <linux/ioport.h>
24 #include <linux/irq.h>
25 #include <linux/mc146818rtc.h>
26 #include <linux/miscdevice.h>
27 #include <linux/module.h>
28 #include <linux/poll.h>
29 #include <linux/rtc.h>
30 #include <linux/spinlock.h>
31 #include <linux/types.h>
32 #include <linux/wait.h>
34 #include <asm/div64.h>
37 #include <asm/uaccess.h>
38 #include <asm/vr41xx/vr41xx.h>
40 MODULE_AUTHOR("Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>");
41 MODULE_DESCRIPTION("NEC VR4100 series RTC driver");
42 MODULE_LICENSE("GPL");
44 #define RTC1_TYPE1_START 0x0b0000c0UL
45 #define RTC1_TYPE1_END 0x0b0000dfUL
46 #define RTC2_TYPE1_START 0x0b0001c0UL
47 #define RTC2_TYPE1_END 0x0b0001dfUL
49 #define RTC1_TYPE2_START 0x0f000100UL
50 #define RTC1_TYPE2_END 0x0f00011fUL
51 #define RTC2_TYPE2_START 0x0f000120UL
52 #define RTC2_TYPE2_END 0x0f00013fUL
54 #define RTC1_SIZE 0x20
55 #define RTC2_SIZE 0x20
58 #define ETIMELREG 0x00
59 #define ETIMEMREG 0x02
60 #define ETIMEHREG 0x04
66 #define RTCL1LREG 0x10
67 #define RTCL1HREG 0x12
68 #define RTCL1CNTLREG 0x14
69 #define RTCL1CNTHREG 0x16
70 #define RTCL2LREG 0x18
71 #define RTCL2HREG 0x1a
72 #define RTCL2CNTLREG 0x1c
73 #define RTCL2CNTHREG 0x1e
78 #define TCLKCNTLREG 0x04
79 #define TCLKCNTHREG 0x06
81 #define RTCINTREG 0x1e
82 #define TCLOCK_INT 0x08
83 #define RTCLONG2_INT 0x04
84 #define RTCLONG1_INT 0x02
85 #define ELAPSEDTIME_INT 0x01
87 #define RTC_FREQUENCY 32768
88 #define MAX_PERIODIC_RATE 6553
89 #define MAX_USER_PERIODIC_RATE 64
91 static void __iomem
*rtc1_base
;
92 static void __iomem
*rtc2_base
;
94 #define rtc1_read(offset) readw(rtc1_base + (offset))
95 #define rtc1_write(offset, value) writew((value), rtc1_base + (offset))
97 #define rtc2_read(offset) readw(rtc2_base + (offset))
98 #define rtc2_write(offset, value) writew((value), rtc2_base + (offset))
100 static unsigned long epoch
= 1970; /* Jan 1 1970 00:00:00 */
102 static spinlock_t rtc_task_lock
;
103 static wait_queue_head_t rtc_wait
;
104 static unsigned long rtc_irq_data
;
105 static struct fasync_struct
*rtc_async_queue
;
106 static rtc_task_t
*rtc_callback
;
107 static char rtc_name
[] = "RTC";
108 static unsigned long periodic_frequency
;
109 static unsigned long periodic_count
;
116 static rtc_status_t rtc_status
;
120 FUNCTION_RTC_CONTROL
,
123 struct resource rtc_resource
[2] = {
125 .flags
= IORESOURCE_MEM
, },
127 .flags
= IORESOURCE_MEM
, },
130 static inline unsigned long read_elapsed_second(void)
132 unsigned long first_low
, first_mid
, first_high
;
133 unsigned long second_low
, second_mid
, second_high
;
136 first_low
= rtc1_read(ETIMELREG
);
137 first_mid
= rtc1_read(ETIMEMREG
);
138 first_high
= rtc1_read(ETIMEHREG
);
139 second_low
= rtc1_read(ETIMELREG
);
140 second_mid
= rtc1_read(ETIMEMREG
);
141 second_high
= rtc1_read(ETIMEHREG
);
142 } while (first_low
!= second_low
|| first_mid
!= second_mid
||
143 first_high
!= second_high
);
145 return (first_high
<< 17) | (first_mid
<< 1) | (first_low
>> 15);
148 static inline void write_elapsed_second(unsigned long sec
)
150 spin_lock_irq(&rtc_lock
);
152 rtc1_write(ETIMELREG
, (uint16_t)(sec
<< 15));
153 rtc1_write(ETIMEMREG
, (uint16_t)(sec
>> 1));
154 rtc1_write(ETIMEHREG
, (uint16_t)(sec
>> 17));
156 spin_unlock_irq(&rtc_lock
);
159 static void set_alarm(struct rtc_time
*time
)
161 unsigned long alarm_sec
;
163 alarm_sec
= mktime(time
->tm_year
+ 1900, time
->tm_mon
+ 1, time
->tm_mday
,
164 time
->tm_hour
, time
->tm_min
, time
->tm_sec
);
166 spin_lock_irq(&rtc_lock
);
168 rtc1_write(ECMPLREG
, (uint16_t)(alarm_sec
<< 15));
169 rtc1_write(ECMPMREG
, (uint16_t)(alarm_sec
>> 1));
170 rtc1_write(ECMPHREG
, (uint16_t)(alarm_sec
>> 17));
172 spin_unlock_irq(&rtc_lock
);
175 static void read_alarm(struct rtc_time
*time
)
177 unsigned long low
, mid
, high
;
179 spin_lock_irq(&rtc_lock
);
181 low
= rtc1_read(ECMPLREG
);
182 mid
= rtc1_read(ECMPMREG
);
183 high
= rtc1_read(ECMPHREG
);
185 spin_unlock_irq(&rtc_lock
);
187 to_tm((high
<< 17) | (mid
<< 1) | (low
>> 15), time
);
188 time
->tm_year
-= 1900;
191 static void read_time(struct rtc_time
*time
)
193 unsigned long epoch_sec
, elapsed_sec
;
195 epoch_sec
= mktime(epoch
, 1, 1, 0, 0, 0);
196 elapsed_sec
= read_elapsed_second();
198 to_tm(epoch_sec
+ elapsed_sec
, time
);
199 time
->tm_year
-= 1900;
202 static void set_time(struct rtc_time
*time
)
204 unsigned long epoch_sec
, current_sec
;
206 epoch_sec
= mktime(epoch
, 1, 1, 0, 0, 0);
207 current_sec
= mktime(time
->tm_year
+ 1900, time
->tm_mon
+ 1, time
->tm_mday
,
208 time
->tm_hour
, time
->tm_min
, time
->tm_sec
);
210 write_elapsed_second(current_sec
- epoch_sec
);
213 static ssize_t
rtc_read(struct file
*file
, char __user
*buf
, size_t count
, loff_t
*ppos
)
215 DECLARE_WAITQUEUE(wait
, current
);
216 unsigned long irq_data
;
219 if (count
!= sizeof(unsigned int) && count
!= sizeof(unsigned long))
222 add_wait_queue(&rtc_wait
, &wait
);
225 __set_current_state(TASK_INTERRUPTIBLE
);
227 spin_lock_irq(&rtc_lock
);
228 irq_data
= rtc_irq_data
;
230 spin_unlock_irq(&rtc_lock
);
235 if (file
->f_flags
& O_NONBLOCK
) {
240 if (signal_pending(current
)) {
241 retval
= -ERESTARTSYS
;
247 if (count
== sizeof(unsigned int)) {
248 retval
= put_user(irq_data
, (unsigned int __user
*)buf
);
250 retval
= sizeof(unsigned int);
252 retval
= put_user(irq_data
, (unsigned long __user
*)buf
);
254 retval
= sizeof(unsigned long);
259 __set_current_state(TASK_RUNNING
);
260 remove_wait_queue(&rtc_wait
, &wait
);
265 static unsigned int rtc_poll(struct file
*file
, struct poll_table_struct
*table
)
267 poll_wait(file
, &rtc_wait
, table
);
269 if (rtc_irq_data
!= 0)
270 return POLLIN
| POLLRDNORM
;
275 static int rtc_do_ioctl(unsigned int cmd
, unsigned long arg
, rtc_callfrom_t from
)
277 struct rtc_time time
;
282 enable_irq(ELAPSEDTIME_IRQ
);
285 disable_irq(ELAPSEDTIME_IRQ
);
288 enable_irq(RTCLONG1_IRQ
);
291 disable_irq(RTCLONG1_IRQ
);
294 if (copy_from_user(&time
, (struct rtc_time __user
*)arg
,
295 sizeof(struct rtc_time
)))
301 memset(&time
, 0, sizeof(struct rtc_time
));
305 memset(&time
, 0, sizeof(struct rtc_time
));
307 if (copy_to_user((void __user
*)arg
, &time
, sizeof(struct rtc_time
)))
311 if (capable(CAP_SYS_TIME
) == 0)
314 if (copy_from_user(&time
, (struct rtc_time __user
*)arg
,
315 sizeof(struct rtc_time
)))
321 return put_user(periodic_frequency
, (unsigned long __user
*)arg
);
324 if (arg
> MAX_PERIODIC_RATE
)
327 if (from
== FUNCTION_RTC_IOCTL
&& arg
> MAX_USER_PERIODIC_RATE
&&
328 capable(CAP_SYS_RESOURCE
) == 0)
331 periodic_frequency
= arg
;
333 count
= RTC_FREQUENCY
;
336 periodic_count
= count
;
338 spin_lock_irq(&rtc_lock
);
340 rtc1_write(RTCL1LREG
, count
);
341 rtc1_write(RTCL1HREG
, count
>> 16);
343 spin_unlock_irq(&rtc_lock
);
346 return put_user(epoch
, (unsigned long __user
*)arg
);
348 /* Doesn't support before 1900 */
352 if (capable(CAP_SYS_TIME
) == 0)
364 static int rtc_ioctl(struct inode
*inode
, struct file
*file
, unsigned int cmd
,
367 return rtc_do_ioctl(cmd
, arg
, FUNCTION_RTC_IOCTL
);
370 static int rtc_open(struct inode
*inode
, struct file
*file
)
372 spin_lock_irq(&rtc_lock
);
374 if (rtc_status
== RTC_OPEN
) {
375 spin_unlock_irq(&rtc_lock
);
379 rtc_status
= RTC_OPEN
;
382 spin_unlock_irq(&rtc_lock
);
387 static int rtc_release(struct inode
*inode
, struct file
*file
)
389 if (file
->f_flags
& FASYNC
)
390 (void)fasync_helper(-1, file
, 0, &rtc_async_queue
);
392 spin_lock_irq(&rtc_lock
);
394 rtc1_write(ECMPLREG
, 0);
395 rtc1_write(ECMPMREG
, 0);
396 rtc1_write(ECMPHREG
, 0);
397 rtc1_write(RTCL1LREG
, 0);
398 rtc1_write(RTCL1HREG
, 0);
400 rtc_status
= RTC_RELEASE
;
402 spin_unlock_irq(&rtc_lock
);
404 disable_irq(ELAPSEDTIME_IRQ
);
405 disable_irq(RTCLONG1_IRQ
);
410 static int rtc_fasync(int fd
, struct file
*file
, int on
)
412 return fasync_helper(fd
, file
, on
, &rtc_async_queue
);
415 static struct file_operations rtc_fops
= {
416 .owner
= THIS_MODULE
,
422 .release
= rtc_release
,
423 .fasync
= rtc_fasync
,
426 static irqreturn_t
elapsedtime_interrupt(int irq
, void *dev_id
, struct pt_regs
*regs
)
428 spin_lock(&rtc_lock
);
429 rtc2_write(RTCINTREG
, ELAPSEDTIME_INT
);
431 rtc_irq_data
+= 0x100;
432 rtc_irq_data
&= ~0xff;
433 rtc_irq_data
|= RTC_AF
;
434 spin_unlock(&rtc_lock
);
436 spin_lock(&rtc_lock
);
438 rtc_callback
->func(rtc_callback
->private_data
);
439 spin_unlock(&rtc_lock
);
441 wake_up_interruptible(&rtc_wait
);
443 kill_fasync(&rtc_async_queue
, SIGIO
, POLL_IN
);
448 static irqreturn_t
rtclong1_interrupt(int irq
, void *dev_id
, struct pt_regs
*regs
)
450 unsigned long count
= periodic_count
;
452 spin_lock(&rtc_lock
);
453 rtc2_write(RTCINTREG
, RTCLONG1_INT
);
455 rtc1_write(RTCL1LREG
, count
);
456 rtc1_write(RTCL1HREG
, count
>> 16);
458 rtc_irq_data
+= 0x100;
459 rtc_irq_data
&= ~0xff;
460 rtc_irq_data
|= RTC_PF
;
461 spin_unlock(&rtc_lock
);
463 spin_lock(&rtc_task_lock
);
465 rtc_callback
->func(rtc_callback
->private_data
);
466 spin_unlock(&rtc_task_lock
);
468 wake_up_interruptible(&rtc_wait
);
470 kill_fasync(&rtc_async_queue
, SIGIO
, POLL_IN
);
475 int rtc_register(rtc_task_t
*task
)
477 if (task
== NULL
|| task
->func
== NULL
)
480 spin_lock_irq(&rtc_lock
);
481 if (rtc_status
== RTC_OPEN
) {
482 spin_unlock_irq(&rtc_lock
);
486 spin_lock(&rtc_task_lock
);
487 if (rtc_callback
!= NULL
) {
488 spin_unlock(&rtc_task_lock
);
489 spin_unlock_irq(&rtc_task_lock
);
494 spin_unlock(&rtc_task_lock
);
496 rtc_status
= RTC_OPEN
;
498 spin_unlock_irq(&rtc_lock
);
503 EXPORT_SYMBOL_GPL(rtc_register
);
505 int rtc_unregister(rtc_task_t
*task
)
507 spin_lock_irq(&rtc_task_lock
);
508 if (task
== NULL
|| rtc_callback
!= task
) {
509 spin_unlock_irq(&rtc_task_lock
);
513 spin_lock(&rtc_lock
);
515 rtc1_write(ECMPLREG
, 0);
516 rtc1_write(ECMPMREG
, 0);
517 rtc1_write(ECMPHREG
, 0);
518 rtc1_write(RTCL1LREG
, 0);
519 rtc1_write(RTCL1HREG
, 0);
521 rtc_status
= RTC_RELEASE
;
523 spin_unlock(&rtc_lock
);
527 spin_unlock_irq(&rtc_task_lock
);
529 disable_irq(ELAPSEDTIME_IRQ
);
530 disable_irq(RTCLONG1_IRQ
);
535 EXPORT_SYMBOL_GPL(rtc_unregister
);
537 int rtc_control(rtc_task_t
*task
, unsigned int cmd
, unsigned long arg
)
541 spin_lock_irq(&rtc_task_lock
);
543 if (rtc_callback
!= task
)
546 rtc_do_ioctl(cmd
, arg
, FUNCTION_RTC_CONTROL
);
548 spin_unlock_irq(&rtc_task_lock
);
553 EXPORT_SYMBOL_GPL(rtc_control
);
555 static struct miscdevice rtc_miscdevice
= {
561 static int rtc_probe(struct platform_device
*pdev
)
566 if (pdev
->num_resources
!= 2)
569 rtc1_base
= ioremap(pdev
->resource
[0].start
, RTC1_SIZE
);
570 if (rtc1_base
== NULL
)
573 rtc2_base
= ioremap(pdev
->resource
[1].start
, RTC2_SIZE
);
574 if (rtc2_base
== NULL
) {
580 retval
= misc_register(&rtc_miscdevice
);
589 spin_lock_irq(&rtc_lock
);
591 rtc1_write(ECMPLREG
, 0);
592 rtc1_write(ECMPMREG
, 0);
593 rtc1_write(ECMPHREG
, 0);
594 rtc1_write(RTCL1LREG
, 0);
595 rtc1_write(RTCL1HREG
, 0);
597 rtc_status
= RTC_RELEASE
;
600 spin_unlock_irq(&rtc_lock
);
602 init_waitqueue_head(&rtc_wait
);
604 irq
= ELAPSEDTIME_IRQ
;
605 retval
= request_irq(irq
, elapsedtime_interrupt
, SA_INTERRUPT
,
606 "elapsed_time", NULL
);
609 retval
= request_irq(irq
, rtclong1_interrupt
, SA_INTERRUPT
,
614 printk(KERN_ERR
"rtc: IRQ%d is busy\n", irq
);
615 if (irq
== RTCLONG1_IRQ
)
616 free_irq(ELAPSEDTIME_IRQ
, NULL
);
624 disable_irq(ELAPSEDTIME_IRQ
);
625 disable_irq(RTCLONG1_IRQ
);
627 spin_lock_init(&rtc_task_lock
);
629 printk(KERN_INFO
"rtc: Real Time Clock of NEC VR4100 series\n");
634 static int rtc_remove(struct platform_device
*dev
)
638 retval
= misc_deregister(&rtc_miscdevice
);
642 free_irq(ELAPSEDTIME_IRQ
, NULL
);
643 free_irq(RTCLONG1_IRQ
, NULL
);
644 if (rtc1_base
!= NULL
)
646 if (rtc2_base
!= NULL
)
652 static struct platform_device
*rtc_platform_device
;
654 static struct platform_driver rtc_device_driver
= {
656 .remove
= rtc_remove
,
662 static int __devinit
vr41xx_rtc_init(void)
666 switch (current_cpu_data
.cputype
) {
669 rtc_resource
[0].start
= RTC1_TYPE1_START
;
670 rtc_resource
[0].end
= RTC1_TYPE1_END
;
671 rtc_resource
[1].start
= RTC2_TYPE1_START
;
672 rtc_resource
[1].end
= RTC2_TYPE1_END
;
677 rtc_resource
[0].start
= RTC1_TYPE2_START
;
678 rtc_resource
[0].end
= RTC1_TYPE2_END
;
679 rtc_resource
[1].start
= RTC2_TYPE2_START
;
680 rtc_resource
[1].end
= RTC2_TYPE2_END
;
687 rtc_platform_device
= platform_device_register_simple("RTC", -1,
688 rtc_resource
, ARRAY_SIZE(rtc_resource
));
689 if (IS_ERR(rtc_platform_device
))
690 return PTR_ERR(rtc_platform_device
);
692 retval
= platform_driver_register(&rtc_device_driver
);
694 platform_device_unregister(rtc_platform_device
);
699 static void __devexit
vr41xx_rtc_exit(void)
701 platform_driver_unregister(&rtc_device_driver
);
703 platform_device_unregister(rtc_platform_device
);
706 module_init(vr41xx_rtc_init
);
707 module_exit(vr41xx_rtc_exit
);