blob: fee41b97c9e89e3835734454a720fb772ed17202 [file] [log] [blame]
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -07001/*
2 * An rtc driver for the Dallas DS1553
3 *
4 * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.jp>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/bcd.h>
12#include <linux/init.h>
13#include <linux/kernel.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090014#include <linux/gfp.h>
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -070015#include <linux/delay.h>
16#include <linux/jiffies.h>
17#include <linux/interrupt.h>
18#include <linux/rtc.h>
19#include <linux/platform_device.h>
20#include <linux/io.h>
21
Atsushi Nemoto618161f2009-12-15 16:46:01 -080022#define DRV_VERSION "0.3"
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -070023
24#define RTC_REG_SIZE 0x2000
25#define RTC_OFFSET 0x1ff0
26
27#define RTC_FLAGS (RTC_OFFSET + 0)
28#define RTC_SECONDS_ALARM (RTC_OFFSET + 2)
29#define RTC_MINUTES_ALARM (RTC_OFFSET + 3)
30#define RTC_HOURS_ALARM (RTC_OFFSET + 4)
31#define RTC_DATE_ALARM (RTC_OFFSET + 5)
32#define RTC_INTERRUPTS (RTC_OFFSET + 6)
33#define RTC_WATCHDOG (RTC_OFFSET + 7)
34#define RTC_CONTROL (RTC_OFFSET + 8)
35#define RTC_CENTURY (RTC_OFFSET + 8)
36#define RTC_SECONDS (RTC_OFFSET + 9)
37#define RTC_MINUTES (RTC_OFFSET + 10)
38#define RTC_HOURS (RTC_OFFSET + 11)
39#define RTC_DAY (RTC_OFFSET + 12)
40#define RTC_DATE (RTC_OFFSET + 13)
41#define RTC_MONTH (RTC_OFFSET + 14)
42#define RTC_YEAR (RTC_OFFSET + 15)
43
44#define RTC_CENTURY_MASK 0x3f
45#define RTC_SECONDS_MASK 0x7f
46#define RTC_DAY_MASK 0x07
47
48/* Bits in the Control/Century register */
49#define RTC_WRITE 0x80
50#define RTC_READ 0x40
51
52/* Bits in the Seconds register */
53#define RTC_STOP 0x80
54
55/* Bits in the Flags register */
56#define RTC_FLAGS_AF 0x40
57#define RTC_FLAGS_BLF 0x10
58
59/* Bits in the Interrupts register */
60#define RTC_INTS_AE 0x80
61
62struct rtc_plat_data {
63 struct rtc_device *rtc;
64 void __iomem *ioaddr;
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -070065 unsigned long last_jiffies;
66 int irq;
67 unsigned int irqen;
68 int alrm_sec;
69 int alrm_min;
70 int alrm_hour;
71 int alrm_mday;
Atsushi Nemoto618161f2009-12-15 16:46:01 -080072 spinlock_t lock;
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -070073};
74
75static int ds1553_rtc_set_time(struct device *dev, struct rtc_time *tm)
76{
77 struct platform_device *pdev = to_platform_device(dev);
78 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
79 void __iomem *ioaddr = pdata->ioaddr;
80 u8 century;
81
Adrian Bunkfe20ba72008-10-18 20:28:41 -070082 century = bin2bcd((tm->tm_year + 1900) / 100);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -070083
84 writeb(RTC_WRITE, pdata->ioaddr + RTC_CONTROL);
85
Adrian Bunkfe20ba72008-10-18 20:28:41 -070086 writeb(bin2bcd(tm->tm_year % 100), ioaddr + RTC_YEAR);
87 writeb(bin2bcd(tm->tm_mon + 1), ioaddr + RTC_MONTH);
88 writeb(bin2bcd(tm->tm_wday) & RTC_DAY_MASK, ioaddr + RTC_DAY);
89 writeb(bin2bcd(tm->tm_mday), ioaddr + RTC_DATE);
90 writeb(bin2bcd(tm->tm_hour), ioaddr + RTC_HOURS);
91 writeb(bin2bcd(tm->tm_min), ioaddr + RTC_MINUTES);
92 writeb(bin2bcd(tm->tm_sec) & RTC_SECONDS_MASK, ioaddr + RTC_SECONDS);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -070093
94 /* RTC_CENTURY and RTC_CONTROL share same register */
95 writeb(RTC_WRITE | (century & RTC_CENTURY_MASK), ioaddr + RTC_CENTURY);
96 writeb(century & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
97 return 0;
98}
99
100static int ds1553_rtc_read_time(struct device *dev, struct rtc_time *tm)
101{
102 struct platform_device *pdev = to_platform_device(dev);
103 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
104 void __iomem *ioaddr = pdata->ioaddr;
105 unsigned int year, month, day, hour, minute, second, week;
106 unsigned int century;
107
108 /* give enough time to update RTC in case of continuous read */
109 if (pdata->last_jiffies == jiffies)
110 msleep(1);
111 pdata->last_jiffies = jiffies;
112 writeb(RTC_READ, ioaddr + RTC_CONTROL);
113 second = readb(ioaddr + RTC_SECONDS) & RTC_SECONDS_MASK;
114 minute = readb(ioaddr + RTC_MINUTES);
115 hour = readb(ioaddr + RTC_HOURS);
116 day = readb(ioaddr + RTC_DATE);
117 week = readb(ioaddr + RTC_DAY) & RTC_DAY_MASK;
118 month = readb(ioaddr + RTC_MONTH);
119 year = readb(ioaddr + RTC_YEAR);
120 century = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
121 writeb(0, ioaddr + RTC_CONTROL);
Adrian Bunkfe20ba72008-10-18 20:28:41 -0700122 tm->tm_sec = bcd2bin(second);
123 tm->tm_min = bcd2bin(minute);
124 tm->tm_hour = bcd2bin(hour);
125 tm->tm_mday = bcd2bin(day);
126 tm->tm_wday = bcd2bin(week);
127 tm->tm_mon = bcd2bin(month) - 1;
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700128 /* year is 1900 + tm->tm_year */
Adrian Bunkfe20ba72008-10-18 20:28:41 -0700129 tm->tm_year = bcd2bin(year) + bcd2bin(century) * 100 - 1900;
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700130
131 if (rtc_valid_tm(tm) < 0) {
132 dev_err(dev, "retrieved date/time is not valid.\n");
133 rtc_time_to_tm(0, tm);
134 }
135 return 0;
136}
137
138static void ds1553_rtc_update_alarm(struct rtc_plat_data *pdata)
139{
140 void __iomem *ioaddr = pdata->ioaddr;
141 unsigned long flags;
142
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800143 spin_lock_irqsave(&pdata->lock, flags);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700144 writeb(pdata->alrm_mday < 0 || (pdata->irqen & RTC_UF) ?
Adrian Bunkfe20ba72008-10-18 20:28:41 -0700145 0x80 : bin2bcd(pdata->alrm_mday),
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700146 ioaddr + RTC_DATE_ALARM);
147 writeb(pdata->alrm_hour < 0 || (pdata->irqen & RTC_UF) ?
Adrian Bunkfe20ba72008-10-18 20:28:41 -0700148 0x80 : bin2bcd(pdata->alrm_hour),
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700149 ioaddr + RTC_HOURS_ALARM);
150 writeb(pdata->alrm_min < 0 || (pdata->irqen & RTC_UF) ?
Adrian Bunkfe20ba72008-10-18 20:28:41 -0700151 0x80 : bin2bcd(pdata->alrm_min),
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700152 ioaddr + RTC_MINUTES_ALARM);
153 writeb(pdata->alrm_sec < 0 || (pdata->irqen & RTC_UF) ?
Adrian Bunkfe20ba72008-10-18 20:28:41 -0700154 0x80 : bin2bcd(pdata->alrm_sec),
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700155 ioaddr + RTC_SECONDS_ALARM);
156 writeb(pdata->irqen ? RTC_INTS_AE : 0, ioaddr + RTC_INTERRUPTS);
157 readb(ioaddr + RTC_FLAGS); /* clear interrupts */
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800158 spin_unlock_irqrestore(&pdata->lock, flags);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700159}
160
161static int ds1553_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
162{
163 struct platform_device *pdev = to_platform_device(dev);
164 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
165
Anton Vorontsov2fac6672009-01-06 14:42:11 -0800166 if (pdata->irq <= 0)
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700167 return -EINVAL;
168 pdata->alrm_mday = alrm->time.tm_mday;
169 pdata->alrm_hour = alrm->time.tm_hour;
170 pdata->alrm_min = alrm->time.tm_min;
171 pdata->alrm_sec = alrm->time.tm_sec;
172 if (alrm->enabled)
173 pdata->irqen |= RTC_AF;
174 ds1553_rtc_update_alarm(pdata);
175 return 0;
176}
177
178static int ds1553_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
179{
180 struct platform_device *pdev = to_platform_device(dev);
181 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
182
Anton Vorontsov2fac6672009-01-06 14:42:11 -0800183 if (pdata->irq <= 0)
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700184 return -EINVAL;
185 alrm->time.tm_mday = pdata->alrm_mday < 0 ? 0 : pdata->alrm_mday;
186 alrm->time.tm_hour = pdata->alrm_hour < 0 ? 0 : pdata->alrm_hour;
187 alrm->time.tm_min = pdata->alrm_min < 0 ? 0 : pdata->alrm_min;
188 alrm->time.tm_sec = pdata->alrm_sec < 0 ? 0 : pdata->alrm_sec;
189 alrm->enabled = (pdata->irqen & RTC_AF) ? 1 : 0;
190 return 0;
191}
192
David Howells7d12e782006-10-05 14:55:46 +0100193static irqreturn_t ds1553_rtc_interrupt(int irq, void *dev_id)
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700194{
195 struct platform_device *pdev = dev_id;
196 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
197 void __iomem *ioaddr = pdata->ioaddr;
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800198 unsigned long events = 0;
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700199
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800200 spin_lock(&pdata->lock);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700201 /* read and clear interrupt */
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800202 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_AF) {
203 events = RTC_IRQF;
204 if (readb(ioaddr + RTC_SECONDS_ALARM) & 0x80)
205 events |= RTC_UF;
206 else
207 events |= RTC_AF;
208 if (likely(pdata->rtc))
209 rtc_update_irq(pdata->rtc, 1, events);
210 }
211 spin_unlock(&pdata->lock);
212 return events ? IRQ_HANDLED : IRQ_NONE;
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700213}
214
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800215static int ds1553_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700216{
217 struct platform_device *pdev = to_platform_device(dev);
218 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
219
Anton Vorontsov2fac6672009-01-06 14:42:11 -0800220 if (pdata->irq <= 0)
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800221 return -EINVAL;
222 if (enabled)
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700223 pdata->irqen |= RTC_AF;
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800224 else
225 pdata->irqen &= ~RTC_AF;
226 ds1553_rtc_update_alarm(pdata);
227 return 0;
228}
229
David Brownellff8371a2006-09-30 23:28:17 -0700230static const struct rtc_class_ops ds1553_rtc_ops = {
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800231 .read_time = ds1553_rtc_read_time,
232 .set_time = ds1553_rtc_set_time,
233 .read_alarm = ds1553_rtc_read_alarm,
234 .set_alarm = ds1553_rtc_set_alarm,
235 .alarm_irq_enable = ds1553_rtc_alarm_irq_enable,
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700236};
237
Chris Wright2c3c8be2010-05-12 18:28:57 -0700238static ssize_t ds1553_nvram_read(struct file *filp, struct kobject *kobj,
Zhang Rui91a69022007-06-09 13:57:22 +0800239 struct bin_attribute *bin_attr,
240 char *buf, loff_t pos, size_t size)
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700241{
Atsushi Nemoto50e49be2009-12-15 16:46:04 -0800242 struct device *dev = container_of(kobj, struct device, kobj);
243 struct platform_device *pdev = to_platform_device(dev);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700244 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
245 void __iomem *ioaddr = pdata->ioaddr;
246 ssize_t count;
247
248 for (count = 0; size > 0 && pos < RTC_OFFSET; count++, size--)
249 *buf++ = readb(ioaddr + pos++);
250 return count;
251}
252
Chris Wright2c3c8be2010-05-12 18:28:57 -0700253static ssize_t ds1553_nvram_write(struct file *filp, struct kobject *kobj,
Zhang Rui91a69022007-06-09 13:57:22 +0800254 struct bin_attribute *bin_attr,
255 char *buf, loff_t pos, size_t size)
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700256{
Atsushi Nemoto50e49be2009-12-15 16:46:04 -0800257 struct device *dev = container_of(kobj, struct device, kobj);
258 struct platform_device *pdev = to_platform_device(dev);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700259 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
260 void __iomem *ioaddr = pdata->ioaddr;
261 ssize_t count;
262
263 for (count = 0; size > 0 && pos < RTC_OFFSET; count++, size--)
264 writeb(*buf++, ioaddr + pos++);
265 return count;
266}
267
268static struct bin_attribute ds1553_nvram_attr = {
269 .attr = {
270 .name = "nvram",
David Brownella4b1d502007-11-14 16:58:30 -0800271 .mode = S_IRUGO | S_IWUSR,
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700272 },
273 .size = RTC_OFFSET,
274 .read = ds1553_nvram_read,
275 .write = ds1553_nvram_write,
276};
277
Prarit Bhargavac2391222007-02-12 00:52:29 -0800278static int __devinit ds1553_rtc_probe(struct platform_device *pdev)
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700279{
280 struct rtc_device *rtc;
281 struct resource *res;
282 unsigned int cen, sec;
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800283 struct rtc_plat_data *pdata;
284 void __iomem *ioaddr;
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700285 int ret = 0;
286
287 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
288 if (!res)
289 return -ENODEV;
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800290 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700291 if (!pdata)
292 return -ENOMEM;
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800293 if (!devm_request_mem_region(&pdev->dev, res->start, RTC_REG_SIZE,
294 pdev->name))
295 return -EBUSY;
296
297 ioaddr = devm_ioremap(&pdev->dev, res->start, RTC_REG_SIZE);
298 if (!ioaddr)
299 return -ENOMEM;
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700300 pdata->ioaddr = ioaddr;
301 pdata->irq = platform_get_irq(pdev, 0);
302
303 /* turn RTC on if it was not on */
304 sec = readb(ioaddr + RTC_SECONDS);
305 if (sec & RTC_STOP) {
306 sec &= RTC_SECONDS_MASK;
307 cen = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
308 writeb(RTC_WRITE, ioaddr + RTC_CONTROL);
309 writeb(sec, ioaddr + RTC_SECONDS);
310 writeb(cen & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
311 }
312 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_BLF)
313 dev_warn(&pdev->dev, "voltage-low detected.\n");
314
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800315 spin_lock_init(&pdata->lock);
316 pdata->last_jiffies = jiffies;
317 platform_set_drvdata(pdev, pdata);
Anton Vorontsov2fac6672009-01-06 14:42:11 -0800318 if (pdata->irq > 0) {
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700319 writeb(0, ioaddr + RTC_INTERRUPTS);
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800320 if (devm_request_irq(&pdev->dev, pdata->irq,
321 ds1553_rtc_interrupt,
Atsushi Nemoto014b6e92009-06-17 16:26:13 -0700322 IRQF_DISABLED, pdev->name, pdev) < 0) {
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700323 dev_warn(&pdev->dev, "interrupt not available.\n");
Anton Vorontsov2fac6672009-01-06 14:42:11 -0800324 pdata->irq = 0;
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700325 }
326 }
327
328 rtc = rtc_device_register(pdev->name, &pdev->dev,
329 &ds1553_rtc_ops, THIS_MODULE);
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800330 if (IS_ERR(rtc))
331 return PTR_ERR(rtc);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700332 pdata->rtc = rtc;
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800333
Atsushi Nemoto391b1fe2006-09-30 23:28:18 -0700334 ret = sysfs_create_bin_file(&pdev->dev.kobj, &ds1553_nvram_attr);
335 if (ret)
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800336 rtc_device_unregister(rtc);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700337 return ret;
338}
339
340static int __devexit ds1553_rtc_remove(struct platform_device *pdev)
341{
342 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
343
344 sysfs_remove_bin_file(&pdev->dev.kobj, &ds1553_nvram_attr);
345 rtc_device_unregister(pdata->rtc);
Atsushi Nemoto618161f2009-12-15 16:46:01 -0800346 if (pdata->irq > 0)
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700347 writeb(0, pdata->ioaddr + RTC_INTERRUPTS);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700348 return 0;
349}
350
Kay Sieversad28a072008-04-10 21:29:25 -0700351/* work with hotplug and coldplug */
352MODULE_ALIAS("platform:rtc-ds1553");
353
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700354static struct platform_driver ds1553_rtc_driver = {
355 .probe = ds1553_rtc_probe,
356 .remove = __devexit_p(ds1553_rtc_remove),
357 .driver = {
Atsushi Nemotoe7634c22007-10-16 01:28:17 -0700358 .name = "rtc-ds1553",
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700359 .owner = THIS_MODULE,
360 },
361};
362
363static __init int ds1553_init(void)
364{
365 return platform_driver_register(&ds1553_rtc_driver);
366}
367
368static __exit void ds1553_exit(void)
369{
Atsushi Nemotoef154ec2007-07-21 04:37:55 -0700370 platform_driver_unregister(&ds1553_rtc_driver);
Atsushi Nemoto9bf5b4f2006-06-25 05:48:28 -0700371}
372
373module_init(ds1553_init);
374module_exit(ds1553_exit);
375
376MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
377MODULE_DESCRIPTION("Dallas DS1553 RTC driver");
378MODULE_LICENSE("GPL");
379MODULE_VERSION(DRV_VERSION);