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12#include <linux/module.h>
13#include <linux/kernel.h>
14#include <linux/init.h>
15#include <linux/platform_device.h>
16#include <linux/rtc.h>
17#include <linux/mfd/abx500.h>
18#include <linux/mfd/ab8500.h>
19#include <linux/delay.h>
20
21#define AB8500_RTC_SOFF_STAT_REG 0x00
22#define AB8500_RTC_CC_CONF_REG 0x01
23#define AB8500_RTC_READ_REQ_REG 0x02
24#define AB8500_RTC_WATCH_TSECMID_REG 0x03
25#define AB8500_RTC_WATCH_TSECHI_REG 0x04
26#define AB8500_RTC_WATCH_TMIN_LOW_REG 0x05
27#define AB8500_RTC_WATCH_TMIN_MID_REG 0x06
28#define AB8500_RTC_WATCH_TMIN_HI_REG 0x07
29#define AB8500_RTC_ALRM_MIN_LOW_REG 0x08
30#define AB8500_RTC_ALRM_MIN_MID_REG 0x09
31#define AB8500_RTC_ALRM_MIN_HI_REG 0x0A
32#define AB8500_RTC_STAT_REG 0x0B
33#define AB8500_RTC_BKUP_CHG_REG 0x0C
34#define AB8500_RTC_FORCE_BKUP_REG 0x0D
35#define AB8500_RTC_CALIB_REG 0x0E
36#define AB8500_RTC_SWITCH_STAT_REG 0x0F
37
38
39#define RTC_READ_REQUEST 0x01
40#define RTC_WRITE_REQUEST 0x02
41
42
43#define RTC_ALARM_ENA 0x04
44#define RTC_STATUS_DATA 0x01
45
46#define COUNTS_PER_SEC (0xF000 / 60)
47#define AB8500_RTC_EPOCH 2000
48
49static const u8 ab8500_rtc_time_regs[] = {
50 AB8500_RTC_WATCH_TMIN_HI_REG, AB8500_RTC_WATCH_TMIN_MID_REG,
51 AB8500_RTC_WATCH_TMIN_LOW_REG, AB8500_RTC_WATCH_TSECHI_REG,
52 AB8500_RTC_WATCH_TSECMID_REG
53};
54
55static const u8 ab8500_rtc_alarm_regs[] = {
56 AB8500_RTC_ALRM_MIN_HI_REG, AB8500_RTC_ALRM_MIN_MID_REG,
57 AB8500_RTC_ALRM_MIN_LOW_REG
58};
59
60
61static unsigned long get_elapsed_seconds(int year)
62{
63 unsigned long secs;
64 struct rtc_time tm = {
65 .tm_year = year - 1900,
66 .tm_mday = 1,
67 };
68
69
70
71
72
73 rtc_tm_to_time(&tm, &secs);
74 return secs;
75}
76
77static int ab8500_rtc_read_time(struct device *dev, struct rtc_time *tm)
78{
79 unsigned long timeout = jiffies + HZ;
80 int retval, i;
81 unsigned long mins, secs;
82 unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
83 u8 value;
84
85
86 retval = abx500_set_register_interruptible(dev,
87 AB8500_RTC, AB8500_RTC_READ_REQ_REG, RTC_READ_REQUEST);
88 if (retval < 0)
89 return retval;
90
91
92 if (abx500_get_chip_id(dev) == 0) {
93 msleep(1);
94 } else {
95
96 while (time_before(jiffies, timeout)) {
97 retval = abx500_get_register_interruptible(dev,
98 AB8500_RTC, AB8500_RTC_READ_REQ_REG, &value);
99 if (retval < 0)
100 return retval;
101
102 if (!(value & RTC_READ_REQUEST))
103 break;
104
105 msleep(1);
106 }
107 }
108
109
110 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
111 retval = abx500_get_register_interruptible(dev,
112 AB8500_RTC, ab8500_rtc_time_regs[i], &value);
113 if (retval < 0)
114 return retval;
115 buf[i] = value;
116 }
117
118 mins = (buf[0] << 16) | (buf[1] << 8) | buf[2];
119
120 secs = (buf[3] << 8) | buf[4];
121 secs = secs / COUNTS_PER_SEC;
122 secs = secs + (mins * 60);
123
124
125 secs += get_elapsed_seconds(AB8500_RTC_EPOCH);
126
127 rtc_time_to_tm(secs, tm);
128 return rtc_valid_tm(tm);
129}
130
131static int ab8500_rtc_set_time(struct device *dev, struct rtc_time *tm)
132{
133 int retval, i;
134 unsigned char buf[ARRAY_SIZE(ab8500_rtc_time_regs)];
135 unsigned long no_secs, no_mins, secs = 0;
136
137 if (tm->tm_year < (AB8500_RTC_EPOCH - 1900)) {
138 dev_dbg(dev, "year should be equal to or greater than %d\n",
139 AB8500_RTC_EPOCH);
140 return -EINVAL;
141 }
142
143
144 rtc_tm_to_time(tm, &secs);
145
146
147
148
149
150 secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
151
152 no_mins = secs / 60;
153
154 no_secs = secs % 60;
155
156 no_secs = no_secs * COUNTS_PER_SEC;
157
158 buf[4] = no_secs & 0xFF;
159 buf[3] = (no_secs >> 8) & 0xFF;
160
161 buf[2] = no_mins & 0xFF;
162 buf[1] = (no_mins >> 8) & 0xFF;
163 buf[0] = (no_mins >> 16) & 0xFF;
164
165 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_time_regs); i++) {
166 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
167 ab8500_rtc_time_regs[i], buf[i]);
168 if (retval < 0)
169 return retval;
170 }
171
172
173 return abx500_set_register_interruptible(dev, AB8500_RTC,
174 AB8500_RTC_READ_REQ_REG, RTC_WRITE_REQUEST);
175}
176
177static int ab8500_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
178{
179 int retval, i;
180 u8 rtc_ctrl, value;
181 unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
182 unsigned long secs, mins;
183
184
185 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
186 AB8500_RTC_STAT_REG, &rtc_ctrl);
187 if (retval < 0)
188 return retval;
189
190 if (rtc_ctrl & RTC_ALARM_ENA)
191 alarm->enabled = 1;
192 else
193 alarm->enabled = 0;
194
195 alarm->pending = 0;
196
197 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
198 retval = abx500_get_register_interruptible(dev, AB8500_RTC,
199 ab8500_rtc_alarm_regs[i], &value);
200 if (retval < 0)
201 return retval;
202 buf[i] = value;
203 }
204
205 mins = (buf[0] << 16) | (buf[1] << 8) | (buf[2]);
206 secs = mins * 60;
207
208
209 secs += get_elapsed_seconds(AB8500_RTC_EPOCH);
210
211 rtc_time_to_tm(secs, &alarm->time);
212
213 return rtc_valid_tm(&alarm->time);
214}
215
216static int ab8500_rtc_irq_enable(struct device *dev, unsigned int enabled)
217{
218 return abx500_mask_and_set_register_interruptible(dev, AB8500_RTC,
219 AB8500_RTC_STAT_REG, RTC_ALARM_ENA,
220 enabled ? RTC_ALARM_ENA : 0);
221}
222
223static int ab8500_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
224{
225 int retval, i;
226 unsigned char buf[ARRAY_SIZE(ab8500_rtc_alarm_regs)];
227 unsigned long mins, secs = 0;
228
229 if (alarm->time.tm_year < (AB8500_RTC_EPOCH - 1900)) {
230 dev_dbg(dev, "year should be equal to or greater than %d\n",
231 AB8500_RTC_EPOCH);
232 return -EINVAL;
233 }
234
235
236 rtc_tm_to_time(&alarm->time, &secs);
237
238
239
240
241
242 secs -= get_elapsed_seconds(AB8500_RTC_EPOCH);
243
244 mins = secs / 60;
245
246 buf[2] = mins & 0xFF;
247 buf[1] = (mins >> 8) & 0xFF;
248 buf[0] = (mins >> 16) & 0xFF;
249
250
251 for (i = 0; i < ARRAY_SIZE(ab8500_rtc_alarm_regs); i++) {
252 retval = abx500_set_register_interruptible(dev, AB8500_RTC,
253 ab8500_rtc_alarm_regs[i], buf[i]);
254 if (retval < 0)
255 return retval;
256 }
257
258 return ab8500_rtc_irq_enable(dev, alarm->enabled);
259}
260
261static irqreturn_t rtc_alarm_handler(int irq, void *data)
262{
263 struct rtc_device *rtc = data;
264 unsigned long events = RTC_IRQF | RTC_AF;
265
266 dev_dbg(&rtc->dev, "%s\n", __func__);
267 rtc_update_irq(rtc, 1, events);
268
269 return IRQ_HANDLED;
270}
271
272static const struct rtc_class_ops ab8500_rtc_ops = {
273 .read_time = ab8500_rtc_read_time,
274 .set_time = ab8500_rtc_set_time,
275 .read_alarm = ab8500_rtc_read_alarm,
276 .set_alarm = ab8500_rtc_set_alarm,
277 .alarm_irq_enable = ab8500_rtc_irq_enable,
278};
279
280static int __devinit ab8500_rtc_probe(struct platform_device *pdev)
281{
282 int err;
283 struct rtc_device *rtc;
284 u8 rtc_ctrl;
285 int irq;
286
287 irq = platform_get_irq_byname(pdev, "ALARM");
288 if (irq < 0)
289 return irq;
290
291
292 err = abx500_mask_and_set_register_interruptible(&pdev->dev, AB8500_RTC,
293 AB8500_RTC_STAT_REG, RTC_STATUS_DATA, RTC_STATUS_DATA);
294 if (err < 0)
295 return err;
296
297
298 msleep(1);
299
300 err = abx500_get_register_interruptible(&pdev->dev, AB8500_RTC,
301 AB8500_RTC_STAT_REG, &rtc_ctrl);
302 if (err < 0)
303 return err;
304
305
306 if (!(rtc_ctrl & RTC_STATUS_DATA)) {
307 dev_err(&pdev->dev, "RTC supply failure\n");
308 return -ENODEV;
309 }
310
311 rtc = rtc_device_register("ab8500-rtc", &pdev->dev, &ab8500_rtc_ops,
312 THIS_MODULE);
313 if (IS_ERR(rtc)) {
314 dev_err(&pdev->dev, "Registration failed\n");
315 err = PTR_ERR(rtc);
316 return err;
317 }
318
319 err = request_threaded_irq(irq, NULL, rtc_alarm_handler, 0,
320 "ab8500-rtc", rtc);
321 if (err < 0) {
322 rtc_device_unregister(rtc);
323 return err;
324 }
325
326 platform_set_drvdata(pdev, rtc);
327
328 return 0;
329}
330
331static int __devexit ab8500_rtc_remove(struct platform_device *pdev)
332{
333 struct rtc_device *rtc = platform_get_drvdata(pdev);
334 int irq = platform_get_irq_byname(pdev, "ALARM");
335
336 free_irq(irq, rtc);
337 rtc_device_unregister(rtc);
338 platform_set_drvdata(pdev, NULL);
339
340 return 0;
341}
342
343static struct platform_driver ab8500_rtc_driver = {
344 .driver = {
345 .name = "ab8500-rtc",
346 .owner = THIS_MODULE,
347 },
348 .probe = ab8500_rtc_probe,
349 .remove = __devexit_p(ab8500_rtc_remove),
350};
351
352static int __init ab8500_rtc_init(void)
353{
354 return platform_driver_register(&ab8500_rtc_driver);
355}
356
357static void __exit ab8500_rtc_exit(void)
358{
359 platform_driver_unregister(&ab8500_rtc_driver);
360}
361
362module_init(ab8500_rtc_init);
363module_exit(ab8500_rtc_exit);
364MODULE_AUTHOR("Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com>");
365MODULE_DESCRIPTION("AB8500 RTC Driver");
366MODULE_LICENSE("GPL v2");
367
