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ocfs2: Make the left masklogs compat.
[taoma-kernel.git] / drivers / rtc / rtc-ds1553.c
blobff432e2ca275a14311165a7e65f93326d3379f6b
1 /*
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>
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
22 #define DRV_VERSION "0.3"
23
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
62 struct rtc_plat_data {
63 struct rtc_device *rtc;
64 void __iomem *ioaddr;
65 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;
72 spinlock_t lock;
73 };
74
75 static 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
82 century = bin2bcd((tm->tm_year + 1900) / 100);
83
84 writeb(RTC_WRITE, pdata->ioaddr + RTC_CONTROL);
85
86 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);
93
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
100 static 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);
122 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;
128 /* year is 1900 + tm->tm_year */
129 tm->tm_year = bcd2bin(year) + bcd2bin(century) * 100 - 1900;
130
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
138 static void ds1553_rtc_update_alarm(struct rtc_plat_data *pdata)
139 {
140 void __iomem *ioaddr = pdata->ioaddr;
141 unsigned long flags;
142
143 spin_lock_irqsave(&pdata->lock, flags);
144 writeb(pdata->alrm_mday < 0 || (pdata->irqen & RTC_UF) ?
145 0x80 : bin2bcd(pdata->alrm_mday),
146 ioaddr + RTC_DATE_ALARM);
147 writeb(pdata->alrm_hour < 0 || (pdata->irqen & RTC_UF) ?
148 0x80 : bin2bcd(pdata->alrm_hour),
149 ioaddr + RTC_HOURS_ALARM);
150 writeb(pdata->alrm_min < 0 || (pdata->irqen & RTC_UF) ?
151 0x80 : bin2bcd(pdata->alrm_min),
152 ioaddr + RTC_MINUTES_ALARM);
153 writeb(pdata->alrm_sec < 0 || (pdata->irqen & RTC_UF) ?
154 0x80 : bin2bcd(pdata->alrm_sec),
155 ioaddr + RTC_SECONDS_ALARM);
156 writeb(pdata->irqen ? RTC_INTS_AE : 0, ioaddr + RTC_INTERRUPTS);
157 readb(ioaddr + RTC_FLAGS); /* clear interrupts */
158 spin_unlock_irqrestore(&pdata->lock, flags);
159 }
160
161 static 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
166 if (pdata->irq <= 0)
167 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
178 static 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
183 if (pdata->irq <= 0)
184 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
193 static irqreturn_t ds1553_rtc_interrupt(int irq, void *dev_id)
194 {
195 struct platform_device *pdev = dev_id;
196 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
197 void __iomem *ioaddr = pdata->ioaddr;
198 unsigned long events = 0;
199
200 spin_lock(&pdata->lock);
201 /* read and clear interrupt */
202 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;
213 }
214
215 static int ds1553_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
216 {
217 struct platform_device *pdev = to_platform_device(dev);
218 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
219
220 if (pdata->irq <= 0)
221 return -EINVAL;
222 if (enabled)
223 pdata->irqen |= RTC_AF;
224 else
225 pdata->irqen &= ~RTC_AF;
226 ds1553_rtc_update_alarm(pdata);
227 return 0;
228 }
229
230 static int ds1553_rtc_update_irq_enable(struct device *dev,
231 unsigned int enabled)
232 {
233 struct platform_device *pdev = to_platform_device(dev);
234 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
235
236 if (pdata->irq <= 0)
237 return -EINVAL;
238 if (enabled)
239 pdata->irqen |= RTC_UF;
240 else
241 pdata->irqen &= ~RTC_UF;
242 ds1553_rtc_update_alarm(pdata);
243 return 0;
244 }
245
246 static const struct rtc_class_ops ds1553_rtc_ops = {
247 .read_time = ds1553_rtc_read_time,
248 .set_time = ds1553_rtc_set_time,
249 .read_alarm = ds1553_rtc_read_alarm,
250 .set_alarm = ds1553_rtc_set_alarm,
251 .alarm_irq_enable = ds1553_rtc_alarm_irq_enable,
252 .update_irq_enable = ds1553_rtc_update_irq_enable,
253 };
254
255 static ssize_t ds1553_nvram_read(struct file *filp, struct kobject *kobj,
256 struct bin_attribute *bin_attr,
257 char *buf, loff_t pos, size_t size)
258 {
259 struct device *dev = container_of(kobj, struct device, kobj);
260 struct platform_device *pdev = to_platform_device(dev);
261 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
262 void __iomem *ioaddr = pdata->ioaddr;
263 ssize_t count;
264
265 for (count = 0; size > 0 && pos < RTC_OFFSET; count++, size--)
266 *buf++ = readb(ioaddr + pos++);
267 return count;
268 }
269
270 static ssize_t ds1553_nvram_write(struct file *filp, struct kobject *kobj,
271 struct bin_attribute *bin_attr,
272 char *buf, loff_t pos, size_t size)
273 {
274 struct device *dev = container_of(kobj, struct device, kobj);
275 struct platform_device *pdev = to_platform_device(dev);
276 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
277 void __iomem *ioaddr = pdata->ioaddr;
278 ssize_t count;
279
280 for (count = 0; size > 0 && pos < RTC_OFFSET; count++, size--)
281 writeb(*buf++, ioaddr + pos++);
282 return count;
283 }
284
285 static struct bin_attribute ds1553_nvram_attr = {
286 .attr = {
287 .name = "nvram",
288 .mode = S_IRUGO | S_IWUSR,
289 },
290 .size = RTC_OFFSET,
291 .read = ds1553_nvram_read,
292 .write = ds1553_nvram_write,
293 };
294
295 static int __devinit ds1553_rtc_probe(struct platform_device *pdev)
296 {
297 struct rtc_device *rtc;
298 struct resource *res;
299 unsigned int cen, sec;
300 struct rtc_plat_data *pdata;
301 void __iomem *ioaddr;
302 int ret = 0;
303
304 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
305 if (!res)
306 return -ENODEV;
307 pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
308 if (!pdata)
309 return -ENOMEM;
310 if (!devm_request_mem_region(&pdev->dev, res->start, RTC_REG_SIZE,
311 pdev->name))
312 return -EBUSY;
313
314 ioaddr = devm_ioremap(&pdev->dev, res->start, RTC_REG_SIZE);
315 if (!ioaddr)
316 return -ENOMEM;
317 pdata->ioaddr = ioaddr;
318 pdata->irq = platform_get_irq(pdev, 0);
319
320 /* turn RTC on if it was not on */
321 sec = readb(ioaddr + RTC_SECONDS);
322 if (sec & RTC_STOP) {
323 sec &= RTC_SECONDS_MASK;
324 cen = readb(ioaddr + RTC_CENTURY) & RTC_CENTURY_MASK;
325 writeb(RTC_WRITE, ioaddr + RTC_CONTROL);
326 writeb(sec, ioaddr + RTC_SECONDS);
327 writeb(cen & RTC_CENTURY_MASK, ioaddr + RTC_CONTROL);
328 }
329 if (readb(ioaddr + RTC_FLAGS) & RTC_FLAGS_BLF)
330 dev_warn(&pdev->dev, "voltage-low detected.\n");
331
332 spin_lock_init(&pdata->lock);
333 pdata->last_jiffies = jiffies;
334 platform_set_drvdata(pdev, pdata);
335 if (pdata->irq > 0) {
336 writeb(0, ioaddr + RTC_INTERRUPTS);
337 if (devm_request_irq(&pdev->dev, pdata->irq,
338 ds1553_rtc_interrupt,
339 IRQF_DISABLED, pdev->name, pdev) < 0) {
340 dev_warn(&pdev->dev, "interrupt not available.\n");
341 pdata->irq = 0;
342 }
343 }
344
345 rtc = rtc_device_register(pdev->name, &pdev->dev,
346 &ds1553_rtc_ops, THIS_MODULE);
347 if (IS_ERR(rtc))
348 return PTR_ERR(rtc);
349 pdata->rtc = rtc;
350
351 ret = sysfs_create_bin_file(&pdev->dev.kobj, &ds1553_nvram_attr);
352 if (ret)
353 rtc_device_unregister(rtc);
354 return ret;
355 }
356
357 static int __devexit ds1553_rtc_remove(struct platform_device *pdev)
358 {
359 struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
360
361 sysfs_remove_bin_file(&pdev->dev.kobj, &ds1553_nvram_attr);
362 rtc_device_unregister(pdata->rtc);
363 if (pdata->irq > 0)
364 writeb(0, pdata->ioaddr + RTC_INTERRUPTS);
365 return 0;
366 }
367
368 /* work with hotplug and coldplug */
369 MODULE_ALIAS("platform:rtc-ds1553");
370
371 static struct platform_driver ds1553_rtc_driver = {
372 .probe = ds1553_rtc_probe,
373 .remove = __devexit_p(ds1553_rtc_remove),
374 .driver = {
375 .name = "rtc-ds1553",
376 .owner = THIS_MODULE,
377 },
378 };
379
380 static __init int ds1553_init(void)
381 {
382 return platform_driver_register(&ds1553_rtc_driver);
383 }
384
385 static __exit void ds1553_exit(void)
386 {
387 platform_driver_unregister(&ds1553_rtc_driver);
388 }
389
390 module_init(ds1553_init);
391 module_exit(ds1553_exit);
392
393 MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
394 MODULE_DESCRIPTION("Dallas DS1553 RTC driver");
395 MODULE_LICENSE("GPL");
396 MODULE_VERSION(DRV_VERSION);
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