include: replace linux/module.h with "struct module" wherever possible
[linux-2.6/next.git] / drivers / rtc / rtc-ds1553.c
blob1350029044e6247247c3220efa362dd3bb832e63
1 /*
2 * An rtc driver for the Dallas DS1553
4 * Copyright (C) 2006 Atsushi Nemoto <anemo@mba.ocn.ne.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 version 2 as
8 * published by the Free Software Foundation.
9 */
11 #include <linux/bcd.h>
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/gfp.h>
15 #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 #include <linux/module.h>
23 #define DRV_VERSION "0.3"
25 #define RTC_REG_SIZE 0x2000
26 #define RTC_OFFSET 0x1ff0
28 #define RTC_FLAGS (RTC_OFFSET + 0)
29 #define RTC_SECONDS_ALARM (RTC_OFFSET + 2)
30 #define RTC_MINUTES_ALARM (RTC_OFFSET + 3)
31 #define RTC_HOURS_ALARM (RTC_OFFSET + 4)
32 #define RTC_DATE_ALARM (RTC_OFFSET + 5)
33 #define RTC_INTERRUPTS (RTC_OFFSET + 6)
34 #define RTC_WATCHDOG (RTC_OFFSET + 7)
35 #define RTC_CONTROL (RTC_OFFSET + 8)
36 #define RTC_CENTURY (RTC_OFFSET + 8)
37 #define RTC_SECONDS (RTC_OFFSET + 9)
38 #define RTC_MINUTES (RTC_OFFSET + 10)
39 #define RTC_HOURS (RTC_OFFSET + 11)
40 #define RTC_DAY (RTC_OFFSET + 12)
41 #define RTC_DATE (RTC_OFFSET + 13)
42 #define RTC_MONTH (RTC_OFFSET + 14)
43 #define RTC_YEAR (RTC_OFFSET + 15)
45 #define RTC_CENTURY_MASK 0x3f
46 #define RTC_SECONDS_MASK 0x7f
47 #define RTC_DAY_MASK 0x07
49 /* Bits in the Control/Century register */
50 #define RTC_WRITE 0x80
51 #define RTC_READ 0x40
53 /* Bits in the Seconds register */
54 #define RTC_STOP 0x80
56 /* Bits in the Flags register */
57 #define RTC_FLAGS_AF 0x40
58 #define RTC_FLAGS_BLF 0x10
60 /* Bits in the Interrupts register */
61 #define RTC_INTS_AE 0x80
63 struct rtc_plat_data {
64 struct rtc_device *rtc;
65 void __iomem *ioaddr;
66 unsigned long last_jiffies;
67 int irq;
68 unsigned int irqen;
69 int alrm_sec;
70 int alrm_min;
71 int alrm_hour;
72 int alrm_mday;
73 spinlock_t lock;
76 static int ds1553_rtc_set_time(struct device *dev, struct rtc_time *tm)
78 struct platform_device *pdev = to_platform_device(dev);
79 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
80 void __iomem *ioaddr = pdata->ioaddr;
81 u8 century;
83 century = bin2bcd((tm->tm_year + 1900) / 100);
85 writeb(RTC_WRITE, pdata->ioaddr + RTC_CONTROL);
87 writeb(bin2bcd(tm->tm_year % 100), ioaddr + RTC_YEAR);
88 writeb(bin2bcd(tm->tm_mon + 1), ioaddr + RTC_MONTH);
89 writeb(bin2bcd(tm->tm_wday) & RTC_DAY_MASK, ioaddr + RTC_DAY);
90 writeb(bin2bcd(tm->tm_mday), ioaddr + RTC_DATE);
91 writeb(bin2bcd(tm->tm_hour), ioaddr + RTC_HOURS);
92 writeb(bin2bcd(tm->tm_min), ioaddr + RTC_MINUTES);
93 writeb(bin2bcd(tm->tm_sec) & RTC_SECONDS_MASK, ioaddr + RTC_SECONDS);
95 /* RTC_CENTURY and RTC_CONTROL share same register */
96 writeb(RTC_WRITE | (century & RTC_CENTURY_MASK), ioaddr + RTC_CENTURY);
97 writeb(century & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
98 return 0;
101 static int ds1553_rtc_read_time(struct device *dev, struct rtc_time *tm)
103 struct platform_device *pdev = to_platform_device(dev);
104 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
105 void __iomem *ioaddr = pdata->ioaddr;
106 unsigned int year, month, day, hour, minute, second, week;
107 unsigned int century;
109 /* give enough time to update RTC in case of continuous read */
110 if (pdata->last_jiffies == jiffies)
111 msleep(1);
112 pdata->last_jiffies = jiffies;
113 writeb(RTC_READ, ioaddr + RTC_CONTROL);
114 second = readb(ioaddr + RTC_SECONDS) & RTC_SECONDS_MASK;
115 minute = readb(ioaddr + RTC_MINUTES);
116 hour = readb(ioaddr + RTC_HOURS);
117 day = readb(ioaddr + RTC_DATE);
118 week = readb(ioaddr + RTC_DAY) & RTC_DAY_MASK;
119 month = readb(ioaddr + RTC_MONTH);
120 year = readb(ioaddr + RTC_YEAR);
121 century = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
122 writeb(0, ioaddr + RTC_CONTROL);
123 tm->tm_sec = bcd2bin(second);
124 tm->tm_min = bcd2bin(minute);
125 tm->tm_hour = bcd2bin(hour);
126 tm->tm_mday = bcd2bin(day);
127 tm->tm_wday = bcd2bin(week);
128 tm->tm_mon = bcd2bin(month) - 1;
129 /* year is 1900 + tm->tm_year */
130 tm->tm_year = bcd2bin(year) + bcd2bin(century) * 100 - 1900;
132 if (rtc_valid_tm(tm) < 0) {
133 dev_err(dev, "retrieved date/time is not valid.\n");
134 rtc_time_to_tm(0, tm);
136 return 0;
139 static void ds1553_rtc_update_alarm(struct rtc_plat_data *pdata)
141 void __iomem *ioaddr = pdata->ioaddr;
142 unsigned long flags;
144 spin_lock_irqsave(&pdata->lock, flags);
145 writeb(pdata->alrm_mday < 0 || (pdata->irqen & RTC_UF) ?
146 0x80 : bin2bcd(pdata->alrm_mday),
147 ioaddr + RTC_DATE_ALARM);
148 writeb(pdata->alrm_hour < 0 || (pdata->irqen & RTC_UF) ?
149 0x80 : bin2bcd(pdata->alrm_hour),
150 ioaddr + RTC_HOURS_ALARM);
151 writeb(pdata->alrm_min < 0 || (pdata->irqen & RTC_UF) ?
152 0x80 : bin2bcd(pdata->alrm_min),
153 ioaddr + RTC_MINUTES_ALARM);
154 writeb(pdata->alrm_sec < 0 || (pdata->irqen & RTC_UF) ?
155 0x80 : bin2bcd(pdata->alrm_sec),
156 ioaddr + RTC_SECONDS_ALARM);
157 writeb(pdata->irqen ? RTC_INTS_AE : 0, ioaddr + RTC_INTERRUPTS);
158 readb(ioaddr + RTC_FLAGS); /* clear interrupts */
159 spin_unlock_irqrestore(&pdata->lock, flags);
162 static int ds1553_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
164 struct platform_device *pdev = to_platform_device(dev);
165 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
167 if (pdata->irq <= 0)
168 return -EINVAL;
169 pdata->alrm_mday = alrm->time.tm_mday;
170 pdata->alrm_hour = alrm->time.tm_hour;
171 pdata->alrm_min = alrm->time.tm_min;
172 pdata->alrm_sec = alrm->time.tm_sec;
173 if (alrm->enabled)
174 pdata->irqen |= RTC_AF;
175 ds1553_rtc_update_alarm(pdata);
176 return 0;
179 static int ds1553_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
181 struct platform_device *pdev = to_platform_device(dev);
182 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
184 if (pdata->irq <= 0)
185 return -EINVAL;
186 alrm->time.tm_mday = pdata->alrm_mday < 0 ? 0 : pdata->alrm_mday;
187 alrm->time.tm_hour = pdata->alrm_hour < 0 ? 0 : pdata->alrm_hour;
188 alrm->time.tm_min = pdata->alrm_min < 0 ? 0 : pdata->alrm_min;
189 alrm->time.tm_sec = pdata->alrm_sec < 0 ? 0 : pdata->alrm_sec;
190 alrm->enabled = (pdata->irqen & RTC_AF) ? 1 : 0;
191 return 0;
194 static irqreturn_t ds1553_rtc_interrupt(int irq, void *dev_id)
196 struct platform_device *pdev = dev_id;
197 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
198 void __iomem *ioaddr = pdata->ioaddr;
199 unsigned long events = 0;
201 spin_lock(&pdata->lock);
202 /* read and clear interrupt */
203 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_AF) {
204 events = RTC_IRQF;
205 if (readb(ioaddr + RTC_SECONDS_ALARM) & 0x80)
206 events |= RTC_UF;
207 else
208 events |= RTC_AF;
209 if (likely(pdata->rtc))
210 rtc_update_irq(pdata->rtc, 1, events);
212 spin_unlock(&pdata->lock);
213 return events ? IRQ_HANDLED : IRQ_NONE;
216 static int ds1553_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
218 struct platform_device *pdev = to_platform_device(dev);
219 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
221 if (pdata->irq <= 0)
222 return -EINVAL;
223 if (enabled)
224 pdata->irqen |= RTC_AF;
225 else
226 pdata->irqen &= ~RTC_AF;
227 ds1553_rtc_update_alarm(pdata);
228 return 0;
231 static const struct rtc_class_ops ds1553_rtc_ops = {
232 .read_time = ds1553_rtc_read_time,
233 .set_time = ds1553_rtc_set_time,
234 .read_alarm = ds1553_rtc_read_alarm,
235 .set_alarm = ds1553_rtc_set_alarm,
236 .alarm_irq_enable = ds1553_rtc_alarm_irq_enable,
239 static ssize_t ds1553_nvram_read(struct file *filp, struct kobject *kobj,
240 struct bin_attribute *bin_attr,
241 char *buf, loff_t pos, size_t size)
243 struct device *dev = container_of(kobj, struct device, kobj);
244 struct platform_device *pdev = to_platform_device(dev);
245 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
246 void __iomem *ioaddr = pdata->ioaddr;
247 ssize_t count;
249 for (count = 0; size > 0 && pos < RTC_OFFSET; count++, size--)
250 *buf++ = readb(ioaddr + pos++);
251 return count;
254 static ssize_t ds1553_nvram_write(struct file *filp, struct kobject *kobj,
255 struct bin_attribute *bin_attr,
256 char *buf, loff_t pos, size_t size)
258 struct device *dev = container_of(kobj, struct device, kobj);
259 struct platform_device *pdev = to_platform_device(dev);
260 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
261 void __iomem *ioaddr = pdata->ioaddr;
262 ssize_t count;
264 for (count = 0; size > 0 && pos < RTC_OFFSET; count++, size--)
265 writeb(*buf++, ioaddr + pos++);
266 return count;
269 static struct bin_attribute ds1553_nvram_attr = {
270 .attr = {
271 .name = "nvram",
272 .mode = S_IRUGO | S_IWUSR,
274 .size = RTC_OFFSET,
275 .read = ds1553_nvram_read,
276 .write = ds1553_nvram_write,
279 static int __devinit ds1553_rtc_probe(struct platform_device *pdev)
281 struct rtc_device *rtc;
282 struct resource *res;
283 unsigned int cen, sec;
284 struct rtc_plat_data *pdata;
285 void __iomem *ioaddr;
286 int ret = 0;
288 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
289 if (!res)
290 return -ENODEV;
291 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
292 if (!pdata)
293 return -ENOMEM;
294 if (!devm_request_mem_region(&pdev->dev, res->start, RTC_REG_SIZE,
295 pdev->name))
296 return -EBUSY;
298 ioaddr = devm_ioremap(&pdev->dev, res->start, RTC_REG_SIZE);
299 if (!ioaddr)
300 return -ENOMEM;
301 pdata->ioaddr = ioaddr;
302 pdata->irq = platform_get_irq(pdev, 0);
304 /* turn RTC on if it was not on */
305 sec = readb(ioaddr + RTC_SECONDS);
306 if (sec & RTC_STOP) {
307 sec &= RTC_SECONDS_MASK;
308 cen = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
309 writeb(RTC_WRITE, ioaddr + RTC_CONTROL);
310 writeb(sec, ioaddr + RTC_SECONDS);
311 writeb(cen & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
313 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_BLF)
314 dev_warn(&pdev->dev, "voltage-low detected.\n");
316 spin_lock_init(&pdata->lock);
317 pdata->last_jiffies = jiffies;
318 platform_set_drvdata(pdev, pdata);
319 if (pdata->irq > 0) {
320 writeb(0, ioaddr + RTC_INTERRUPTS);
321 if (devm_request_irq(&pdev->dev, pdata->irq,
322 ds1553_rtc_interrupt,
323 IRQF_DISABLED, pdev->name, pdev) < 0) {
324 dev_warn(&pdev->dev, "interrupt not available.\n");
325 pdata->irq = 0;
329 rtc = rtc_device_register(pdev->name, &pdev->dev,
330 &ds1553_rtc_ops, THIS_MODULE);
331 if (IS_ERR(rtc))
332 return PTR_ERR(rtc);
333 pdata->rtc = rtc;
335 ret = sysfs_create_bin_file(&pdev->dev.kobj, &ds1553_nvram_attr);
336 if (ret)
337 rtc_device_unregister(rtc);
338 return ret;
341 static int __devexit ds1553_rtc_remove(struct platform_device *pdev)
343 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
345 sysfs_remove_bin_file(&pdev->dev.kobj, &ds1553_nvram_attr);
346 rtc_device_unregister(pdata->rtc);
347 if (pdata->irq > 0)
348 writeb(0, pdata->ioaddr + RTC_INTERRUPTS);
349 return 0;
352 /* work with hotplug and coldplug */
353 MODULE_ALIAS("platform:rtc-ds1553");
355 static struct platform_driver ds1553_rtc_driver = {
356 .probe = ds1553_rtc_probe,
357 .remove = __devexit_p(ds1553_rtc_remove),
358 .driver = {
359 .name = "rtc-ds1553",
360 .owner = THIS_MODULE,
364 static __init int ds1553_init(void)
366 return platform_driver_register(&ds1553_rtc_driver);
369 static __exit void ds1553_exit(void)
371 platform_driver_unregister(&ds1553_rtc_driver);
374 module_init(ds1553_init);
375 module_exit(ds1553_exit);
377 MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
378 MODULE_DESCRIPTION("Dallas DS1553 RTC driver");
379 MODULE_LICENSE("GPL");
380 MODULE_VERSION(DRV_VERSION);