blob: 7163b91bb773bd3a8ef0a3be75d9936ffc116f9b [file] [log] [blame]
Akshay Bhated13d892015-12-03 14:41:21 -05001/*
2 * Driver for the Epson RTC module RX-8010 SJ
3 *
4 * Copyright(C) Timesys Corporation 2015
5 * Copyright(C) General Electric Company 2015
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 *
11 */
12
13#include <linux/bcd.h>
14#include <linux/bitops.h>
15#include <linux/i2c.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/rtc.h>
19
20#define RX8010_SEC 0x10
21#define RX8010_MIN 0x11
22#define RX8010_HOUR 0x12
23#define RX8010_WDAY 0x13
24#define RX8010_MDAY 0x14
25#define RX8010_MONTH 0x15
26#define RX8010_YEAR 0x16
27#define RX8010_YEAR 0x16
28#define RX8010_RESV17 0x17
29#define RX8010_ALMIN 0x18
30#define RX8010_ALHOUR 0x19
31#define RX8010_ALWDAY 0x1A
32#define RX8010_TCOUNT0 0x1B
33#define RX8010_TCOUNT1 0x1C
34#define RX8010_EXT 0x1D
35#define RX8010_FLAG 0x1E
36#define RX8010_CTRL 0x1F
37/* 0x20 to 0x2F are user registers */
38#define RX8010_RESV30 0x30
39#define RX8010_RESV31 0x32
40#define RX8010_IRQ 0x32
41
42#define RX8010_EXT_WADA BIT(3)
43
44#define RX8010_FLAG_VLF BIT(1)
45#define RX8010_FLAG_AF BIT(3)
46#define RX8010_FLAG_TF BIT(4)
47#define RX8010_FLAG_UF BIT(5)
48
49#define RX8010_CTRL_AIE BIT(3)
50#define RX8010_CTRL_UIE BIT(5)
51#define RX8010_CTRL_STOP BIT(6)
52#define RX8010_CTRL_TEST BIT(7)
53
54#define RX8010_ALARM_AE BIT(7)
55
56static const struct i2c_device_id rx8010_id[] = {
57 { "rx8010", 0 },
58 { }
59};
60MODULE_DEVICE_TABLE(i2c, rx8010_id);
61
62struct rx8010_data {
63 struct i2c_client *client;
64 struct rtc_device *rtc;
65 u8 ctrlreg;
66 spinlock_t flags_lock;
67};
68
69static irqreturn_t rx8010_irq_1_handler(int irq, void *dev_id)
70{
71 struct i2c_client *client = dev_id;
72 struct rx8010_data *rx8010 = i2c_get_clientdata(client);
73 int flagreg;
74
75 spin_lock(&rx8010->flags_lock);
76
77 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
78
79 if (flagreg <= 0) {
80 spin_unlock(&rx8010->flags_lock);
81 return IRQ_NONE;
82 }
83
84 if (flagreg & RX8010_FLAG_VLF)
85 dev_warn(&client->dev, "Frequency stop detected\n");
86
87 if (flagreg & RX8010_FLAG_TF) {
88 flagreg &= ~RX8010_FLAG_TF;
89 rtc_update_irq(rx8010->rtc, 1, RTC_PF | RTC_IRQF);
90 }
91
92 if (flagreg & RX8010_FLAG_AF) {
93 flagreg &= ~RX8010_FLAG_AF;
94 rtc_update_irq(rx8010->rtc, 1, RTC_AF | RTC_IRQF);
95 }
96
97 if (flagreg & RX8010_FLAG_UF) {
98 flagreg &= ~RX8010_FLAG_UF;
99 rtc_update_irq(rx8010->rtc, 1, RTC_UF | RTC_IRQF);
100 }
101
102 i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg);
103
104 spin_unlock(&rx8010->flags_lock);
105 return IRQ_HANDLED;
106}
107
108static int rx8010_get_time(struct device *dev, struct rtc_time *dt)
109{
110 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
111 u8 date[7];
112 int flagreg;
113 int err;
114
115 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
116 if (flagreg < 0)
117 return flagreg;
118
119 if (flagreg & RX8010_FLAG_VLF) {
120 dev_warn(dev, "Frequency stop detected\n");
121 return -EINVAL;
122 }
123
124 err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_SEC,
125 7, date);
126 if (err != 7)
127 return err < 0 ? err : -EIO;
128
129 dt->tm_sec = bcd2bin(date[RX8010_SEC - RX8010_SEC] & 0x7f);
130 dt->tm_min = bcd2bin(date[RX8010_MIN - RX8010_SEC] & 0x7f);
131 dt->tm_hour = bcd2bin(date[RX8010_HOUR - RX8010_SEC] & 0x3f);
132 dt->tm_mday = bcd2bin(date[RX8010_MDAY - RX8010_SEC] & 0x3f);
133 dt->tm_mon = bcd2bin(date[RX8010_MONTH - RX8010_SEC] & 0x1f) - 1;
134 dt->tm_year = bcd2bin(date[RX8010_YEAR - RX8010_SEC]) + 100;
135 dt->tm_wday = ffs(date[RX8010_WDAY - RX8010_SEC] & 0x7f);
136
137 return rtc_valid_tm(dt);
138}
139
140static int rx8010_set_time(struct device *dev, struct rtc_time *dt)
141{
142 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
143 u8 date[7];
144 int ctrl, flagreg;
145 int ret;
146 unsigned long irqflags;
147
148 if ((dt->tm_year < 100) || (dt->tm_year > 199))
149 return -EINVAL;
150
151 /* set STOP bit before changing clock/calendar */
152 ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL);
153 if (ctrl < 0)
154 return ctrl;
155 rx8010->ctrlreg = ctrl | RX8010_CTRL_STOP;
156 ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
157 rx8010->ctrlreg);
158 if (ret < 0)
159 return ret;
160
161 date[RX8010_SEC - RX8010_SEC] = bin2bcd(dt->tm_sec);
162 date[RX8010_MIN - RX8010_SEC] = bin2bcd(dt->tm_min);
163 date[RX8010_HOUR - RX8010_SEC] = bin2bcd(dt->tm_hour);
164 date[RX8010_MDAY - RX8010_SEC] = bin2bcd(dt->tm_mday);
165 date[RX8010_MONTH - RX8010_SEC] = bin2bcd(dt->tm_mon + 1);
166 date[RX8010_YEAR - RX8010_SEC] = bin2bcd(dt->tm_year - 100);
167 date[RX8010_WDAY - RX8010_SEC] = bin2bcd(1 << dt->tm_wday);
168
169 ret = i2c_smbus_write_i2c_block_data(rx8010->client,
170 RX8010_SEC, 7, date);
171 if (ret < 0)
172 return ret;
173
174 /* clear STOP bit after changing clock/calendar */
175 ctrl = i2c_smbus_read_byte_data(rx8010->client, RX8010_CTRL);
176 if (ctrl < 0)
177 return ctrl;
178 rx8010->ctrlreg = ctrl & ~RX8010_CTRL_STOP;
179 ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
180 rx8010->ctrlreg);
181 if (ret < 0)
182 return ret;
183
184 spin_lock_irqsave(&rx8010->flags_lock, irqflags);
185
186 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
187 if (flagreg < 0) {
188 spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
189 return flagreg;
190 }
191
192 if (flagreg & RX8010_FLAG_VLF)
193 ret = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG,
194 flagreg & ~RX8010_FLAG_VLF);
195
196 spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
197
198 return 0;
199}
200
201static int rx8010_init_client(struct i2c_client *client)
202{
203 struct rx8010_data *rx8010 = i2c_get_clientdata(client);
204 u8 ctrl[2];
205 int need_clear = 0, err = 0;
206
207 /* Initialize reserved registers as specified in datasheet */
208 err = i2c_smbus_write_byte_data(client, RX8010_RESV17, 0xD8);
209 if (err < 0)
210 return err;
211
212 err = i2c_smbus_write_byte_data(client, RX8010_RESV30, 0x00);
213 if (err < 0)
214 return err;
215
216 err = i2c_smbus_write_byte_data(client, RX8010_RESV31, 0x08);
217 if (err < 0)
218 return err;
219
220 err = i2c_smbus_write_byte_data(client, RX8010_IRQ, 0x00);
221 if (err < 0)
222 return err;
223
224 err = i2c_smbus_read_i2c_block_data(rx8010->client, RX8010_FLAG,
225 2, ctrl);
226 if (err != 2)
227 return err < 0 ? err : -EIO;
228
229 if (ctrl[0] & RX8010_FLAG_VLF)
230 dev_warn(&client->dev, "Frequency stop was detected\n");
231
232 if (ctrl[0] & RX8010_FLAG_AF) {
233 dev_warn(&client->dev, "Alarm was detected\n");
234 need_clear = 1;
235 }
236
237 if (ctrl[0] & RX8010_FLAG_TF)
238 need_clear = 1;
239
240 if (ctrl[0] & RX8010_FLAG_UF)
241 need_clear = 1;
242
243 if (need_clear) {
244 ctrl[0] &= ~(RX8010_FLAG_AF | RX8010_FLAG_TF | RX8010_FLAG_UF);
245 err = i2c_smbus_write_byte_data(client, RX8010_FLAG, ctrl[0]);
246 if (err < 0)
247 return err;
248 }
249
250 rx8010->ctrlreg = (ctrl[1] & ~RX8010_CTRL_TEST);
251
252 return err;
253}
254
255static int rx8010_read_alarm(struct device *dev, struct rtc_wkalrm *t)
256{
257 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
258 struct i2c_client *client = rx8010->client;
259 u8 alarmvals[3];
260 int flagreg;
261 int err;
262
263 err = i2c_smbus_read_i2c_block_data(client, RX8010_ALMIN, 3, alarmvals);
264 if (err != 3)
265 return err < 0 ? err : -EIO;
266
267 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
268 if (flagreg < 0)
269 return flagreg;
270
271 t->time.tm_sec = 0;
272 t->time.tm_min = bcd2bin(alarmvals[0] & 0x7f);
273 t->time.tm_hour = bcd2bin(alarmvals[1] & 0x3f);
274
Uwe Kleine-König56d86a72016-06-28 10:43:45 +0200275 if (!(alarmvals[2] & RX8010_ALARM_AE))
Akshay Bhated13d892015-12-03 14:41:21 -0500276 t->time.tm_mday = bcd2bin(alarmvals[2] & 0x7f);
277
Akshay Bhated13d892015-12-03 14:41:21 -0500278 t->enabled = !!(rx8010->ctrlreg & RX8010_CTRL_AIE);
279 t->pending = (flagreg & RX8010_FLAG_AF) && t->enabled;
280
281 return err;
282}
283
284static int rx8010_set_alarm(struct device *dev, struct rtc_wkalrm *t)
285{
286 struct i2c_client *client = to_i2c_client(dev);
287 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
288 u8 alarmvals[3];
289 int extreg, flagreg;
290 int err;
291 unsigned long irqflags;
292
293 spin_lock_irqsave(&rx8010->flags_lock, irqflags);
294 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
295 if (flagreg < 0) {
296 spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
297 return flagreg;
298 }
299
300 if (rx8010->ctrlreg & (RX8010_CTRL_AIE | RX8010_CTRL_UIE)) {
301 rx8010->ctrlreg &= ~(RX8010_CTRL_AIE | RX8010_CTRL_UIE);
302 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
303 rx8010->ctrlreg);
304 if (err < 0) {
305 spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
306 return err;
307 }
308 }
309
310 flagreg &= ~RX8010_FLAG_AF;
311 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg);
312 spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
313 if (err < 0)
314 return err;
315
316 alarmvals[0] = bin2bcd(t->time.tm_min);
317 alarmvals[1] = bin2bcd(t->time.tm_hour);
318 alarmvals[2] = bin2bcd(t->time.tm_mday);
319
320 err = i2c_smbus_write_i2c_block_data(rx8010->client, RX8010_ALMIN,
321 2, alarmvals);
322 if (err < 0)
323 return err;
324
325 extreg = i2c_smbus_read_byte_data(client, RX8010_EXT);
326 if (extreg < 0)
327 return extreg;
328
329 extreg |= RX8010_EXT_WADA;
330 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_EXT, extreg);
331 if (err < 0)
332 return err;
333
334 if (alarmvals[2] == 0)
335 alarmvals[2] |= RX8010_ALARM_AE;
336
337 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_ALWDAY,
338 alarmvals[2]);
339 if (err < 0)
340 return err;
341
342 if (t->enabled) {
343 if (rx8010->rtc->uie_rtctimer.enabled)
344 rx8010->ctrlreg |= RX8010_CTRL_UIE;
345 if (rx8010->rtc->aie_timer.enabled)
346 rx8010->ctrlreg |=
347 (RX8010_CTRL_AIE | RX8010_CTRL_UIE);
348
349 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
350 rx8010->ctrlreg);
351 if (err < 0)
352 return err;
353 }
354
355 return 0;
356}
357
358static int rx8010_alarm_irq_enable(struct device *dev,
359 unsigned int enabled)
360{
361 struct i2c_client *client = to_i2c_client(dev);
362 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
363 int flagreg;
364 u8 ctrl;
365 int err;
366
367 ctrl = rx8010->ctrlreg;
368
369 if (enabled) {
370 if (rx8010->rtc->uie_rtctimer.enabled)
371 ctrl |= RX8010_CTRL_UIE;
372 if (rx8010->rtc->aie_timer.enabled)
373 ctrl |= (RX8010_CTRL_AIE | RX8010_CTRL_UIE);
374 } else {
375 if (!rx8010->rtc->uie_rtctimer.enabled)
376 ctrl &= ~RX8010_CTRL_UIE;
377 if (!rx8010->rtc->aie_timer.enabled)
378 ctrl &= ~RX8010_CTRL_AIE;
379 }
380
381 flagreg = i2c_smbus_read_byte_data(client, RX8010_FLAG);
382 if (flagreg < 0)
383 return flagreg;
384
385 flagreg &= ~RX8010_FLAG_AF;
386 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_FLAG, flagreg);
387 if (err < 0)
388 return err;
389
390 if (ctrl != rx8010->ctrlreg) {
391 rx8010->ctrlreg = ctrl;
392 err = i2c_smbus_write_byte_data(rx8010->client, RX8010_CTRL,
393 rx8010->ctrlreg);
394 if (err < 0)
395 return err;
396 }
397
398 return 0;
399}
400
401static int rx8010_ioctl(struct device *dev, unsigned int cmd, unsigned long arg)
402{
403 struct i2c_client *client = to_i2c_client(dev);
404 struct rx8010_data *rx8010 = dev_get_drvdata(dev);
405 int ret, tmp;
406 int flagreg;
407 unsigned long irqflags;
408
409 switch (cmd) {
410 case RTC_VL_READ:
411 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
412 if (flagreg < 0)
413 return flagreg;
414
415 tmp = !!(flagreg & RX8010_FLAG_VLF);
416 if (copy_to_user((void __user *)arg, &tmp, sizeof(int)))
417 return -EFAULT;
418
419 return 0;
420
421 case RTC_VL_CLR:
422 spin_lock_irqsave(&rx8010->flags_lock, irqflags);
423 flagreg = i2c_smbus_read_byte_data(rx8010->client, RX8010_FLAG);
424 if (flagreg < 0) {
425 spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
426 return flagreg;
427 }
428
429 flagreg &= ~RX8010_FLAG_VLF;
430 ret = i2c_smbus_write_byte_data(client, RX8010_FLAG, flagreg);
431 spin_unlock_irqrestore(&rx8010->flags_lock, irqflags);
432 if (ret < 0)
433 return ret;
434
435 return 0;
436
437 default:
438 return -ENOIOCTLCMD;
439 }
440}
441
442static struct rtc_class_ops rx8010_rtc_ops = {
443 .read_time = rx8010_get_time,
444 .set_time = rx8010_set_time,
445 .ioctl = rx8010_ioctl,
446};
447
448static int rx8010_probe(struct i2c_client *client,
449 const struct i2c_device_id *id)
450{
451 struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
452 struct rx8010_data *rx8010;
453 int err = 0;
454
455 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA
456 | I2C_FUNC_SMBUS_I2C_BLOCK)) {
457 dev_err(&adapter->dev, "doesn't support required functionality\n");
458 return -EIO;
459 }
460
461 rx8010 = devm_kzalloc(&client->dev, sizeof(struct rx8010_data),
462 GFP_KERNEL);
463 if (!rx8010)
464 return -ENOMEM;
465
466 rx8010->client = client;
467 i2c_set_clientdata(client, rx8010);
468
469 spin_lock_init(&rx8010->flags_lock);
470
471 err = rx8010_init_client(client);
472 if (err)
473 return err;
474
475 if (client->irq > 0) {
476 dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
477 err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
478 rx8010_irq_1_handler,
479 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
480 "rx8010", client);
481
482 if (err) {
483 dev_err(&client->dev, "unable to request IRQ\n");
484 client->irq = 0;
485 } else {
486 rx8010_rtc_ops.read_alarm = rx8010_read_alarm;
487 rx8010_rtc_ops.set_alarm = rx8010_set_alarm;
488 rx8010_rtc_ops.alarm_irq_enable = rx8010_alarm_irq_enable;
489 }
490 }
491
492 rx8010->rtc = devm_rtc_device_register(&client->dev, client->name,
493 &rx8010_rtc_ops, THIS_MODULE);
494
495 if (IS_ERR(rx8010->rtc)) {
496 dev_err(&client->dev, "unable to register the class device\n");
497 return PTR_ERR(rx8010->rtc);
498 }
499
500 rx8010->rtc->max_user_freq = 1;
501
502 return err;
503}
504
505static struct i2c_driver rx8010_driver = {
506 .driver = {
507 .name = "rtc-rx8010",
508 },
509 .probe = rx8010_probe,
510 .id_table = rx8010_id,
511};
512
513module_i2c_driver(rx8010_driver);
514
515MODULE_AUTHOR("Akshay Bhat <akshay.bhat@timesys.com>");
516MODULE_DESCRIPTION("Epson RX8010SJ RTC driver");
517MODULE_LICENSE("GPL v2");