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regulator: s2mps11: Adjust supported buck voltages to real values
[linux/fpc-iii.git] / drivers / rtc / rtc-isl1208.c
blob471e395b20db73d98830c55e2f4f10637c56d278
1 /*
2 * Intersil ISL1208 rtc class driver
3 *
4 * Copyright 2005,2006 Hebert Valerio Riedel <hvr@gnu.org>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
10 *
11 */
12
13 #include <linux/bcd.h>
14 #include <linux/i2c.h>
15 #include <linux/module.h>
16 #include <linux/of_device.h>
17 #include <linux/of_irq.h>
18 #include <linux/rtc.h>
19
20 /* Register map */
21 /* rtc section */
22 #define ISL1208_REG_SC 0x00
23 #define ISL1208_REG_MN 0x01
24 #define ISL1208_REG_HR 0x02
25 #define ISL1208_REG_HR_MIL (1<<7) /* 24h/12h mode */
26 #define ISL1208_REG_HR_PM (1<<5) /* PM/AM bit in 12h mode */
27 #define ISL1208_REG_DT 0x03
28 #define ISL1208_REG_MO 0x04
29 #define ISL1208_REG_YR 0x05
30 #define ISL1208_REG_DW 0x06
31 #define ISL1208_RTC_SECTION_LEN 7
32
33 /* control/status section */
34 #define ISL1208_REG_SR 0x07
35 #define ISL1208_REG_SR_ARST (1<<7) /* auto reset */
36 #define ISL1208_REG_SR_XTOSCB (1<<6) /* crystal oscillator */
37 #define ISL1208_REG_SR_WRTC (1<<4) /* write rtc */
38 #define ISL1208_REG_SR_EVT (1<<3) /* event */
39 #define ISL1208_REG_SR_ALM (1<<2) /* alarm */
40 #define ISL1208_REG_SR_BAT (1<<1) /* battery */
41 #define ISL1208_REG_SR_RTCF (1<<0) /* rtc fail */
42 #define ISL1208_REG_INT 0x08
43 #define ISL1208_REG_INT_ALME (1<<6) /* alarm enable */
44 #define ISL1208_REG_INT_IM (1<<7) /* interrupt/alarm mode */
45 #define ISL1219_REG_EV 0x09
46 #define ISL1219_REG_EV_EVEN (1<<4) /* event detection enable */
47 #define ISL1219_REG_EV_EVIENB (1<<7) /* event in pull-up disable */
48 #define ISL1208_REG_ATR 0x0a
49 #define ISL1208_REG_DTR 0x0b
50
51 /* alarm section */
52 #define ISL1208_REG_SCA 0x0c
53 #define ISL1208_REG_MNA 0x0d
54 #define ISL1208_REG_HRA 0x0e
55 #define ISL1208_REG_DTA 0x0f
56 #define ISL1208_REG_MOA 0x10
57 #define ISL1208_REG_DWA 0x11
58 #define ISL1208_ALARM_SECTION_LEN 6
59
60 /* user section */
61 #define ISL1208_REG_USR1 0x12
62 #define ISL1208_REG_USR2 0x13
63 #define ISL1208_USR_SECTION_LEN 2
64
65 /* event section */
66 #define ISL1219_REG_SCT 0x14
67 #define ISL1219_REG_MNT 0x15
68 #define ISL1219_REG_HRT 0x16
69 #define ISL1219_REG_DTT 0x17
70 #define ISL1219_REG_MOT 0x18
71 #define ISL1219_REG_YRT 0x19
72 #define ISL1219_EVT_SECTION_LEN 6
73
74 static struct i2c_driver isl1208_driver;
75
76 /* ISL1208 various variants */
77 enum isl1208_id {
78 TYPE_ISL1208 = 0,
79 TYPE_ISL1209,
80 TYPE_ISL1218,
81 TYPE_ISL1219,
82 ISL_LAST_ID
83 };
84
85 /* Chip capabilities table */
86 static const struct isl1208_config {
87 const char name[8];
88 unsigned int nvmem_length;
89 unsigned has_tamper:1;
90 unsigned has_timestamp:1;
91 } isl1208_configs[] = {
92 [TYPE_ISL1208] = { "isl1208", 2, false, false },
93 [TYPE_ISL1209] = { "isl1209", 2, true, false },
94 [TYPE_ISL1218] = { "isl1218", 8, false, false },
95 [TYPE_ISL1219] = { "isl1219", 2, true, true },
96 };
97
98 static const struct i2c_device_id isl1208_id[] = {
99 { "isl1208", TYPE_ISL1208 },
100 { "isl1209", TYPE_ISL1209 },
101 { "isl1218", TYPE_ISL1218 },
102 { "isl1219", TYPE_ISL1219 },
103 { }
104 };
105 MODULE_DEVICE_TABLE(i2c, isl1208_id);
106
107 static const struct of_device_id isl1208_of_match[] = {
108 { .compatible = "isil,isl1208", .data = &isl1208_configs[TYPE_ISL1208] },
109 { .compatible = "isil,isl1209", .data = &isl1208_configs[TYPE_ISL1209] },
110 { .compatible = "isil,isl1218", .data = &isl1208_configs[TYPE_ISL1218] },
111 { .compatible = "isil,isl1219", .data = &isl1208_configs[TYPE_ISL1219] },
112 { }
113 };
114 MODULE_DEVICE_TABLE(of, isl1208_of_match);
115
116 /* Device state */
117 struct isl1208_state {
118 struct nvmem_config nvmem_config;
119 struct rtc_device *rtc;
120 const struct isl1208_config *config;
121 };
122
123 /* block read */
124 static int
125 isl1208_i2c_read_regs(struct i2c_client *client, u8 reg, u8 buf[],
126 unsigned len)
127 {
128 int ret;
129
130 WARN_ON(reg > ISL1219_REG_YRT);
131 WARN_ON(reg + len > ISL1219_REG_YRT + 1);
132
133 ret = i2c_smbus_read_i2c_block_data(client, reg, len, buf);
134 return (ret < 0) ? ret : 0;
135 }
136
137 /* block write */
138 static int
139 isl1208_i2c_set_regs(struct i2c_client *client, u8 reg, u8 const buf[],
140 unsigned len)
141 {
142 int ret;
143
144 WARN_ON(reg > ISL1219_REG_YRT);
145 WARN_ON(reg + len > ISL1219_REG_YRT + 1);
146
147 ret = i2c_smbus_write_i2c_block_data(client, reg, len, buf);
148 return (ret < 0) ? ret : 0;
149 }
150
151 /* simple check to see whether we have a isl1208 */
152 static int
153 isl1208_i2c_validate_client(struct i2c_client *client)
154 {
155 u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };
156 u8 zero_mask[ISL1208_RTC_SECTION_LEN] = {
157 0x80, 0x80, 0x40, 0xc0, 0xe0, 0x00, 0xf8
158 };
159 int i;
160 int ret;
161
162 ret = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN);
163 if (ret < 0)
164 return ret;
165
166 for (i = 0; i < ISL1208_RTC_SECTION_LEN; ++i) {
167 if (regs[i] & zero_mask[i]) /* check if bits are cleared */
168 return -ENODEV;
169 }
170
171 return 0;
172 }
173
174 static int
175 isl1208_i2c_get_sr(struct i2c_client *client)
176 {
177 return i2c_smbus_read_byte_data(client, ISL1208_REG_SR);
178 }
179
180 static int
181 isl1208_i2c_get_atr(struct i2c_client *client)
182 {
183 int atr = i2c_smbus_read_byte_data(client, ISL1208_REG_ATR);
184 if (atr < 0)
185 return atr;
186
187 /* The 6bit value in the ATR register controls the load
188 * capacitance C_load * in steps of 0.25pF
189 *
190 * bit (1<<5) of the ATR register is inverted
191 *
192 * C_load(ATR=0x20) = 4.50pF
193 * C_load(ATR=0x00) = 12.50pF
194 * C_load(ATR=0x1f) = 20.25pF
195 *
196 */
197
198 atr &= 0x3f; /* mask out lsb */
199 atr ^= 1 << 5; /* invert 6th bit */
200 atr += 2 * 9; /* add offset of 4.5pF; unit[atr] = 0.25pF */
201
202 return atr;
203 }
204
205 /* returns adjustment value + 100 */
206 static int
207 isl1208_i2c_get_dtr(struct i2c_client *client)
208 {
209 int dtr = i2c_smbus_read_byte_data(client, ISL1208_REG_DTR);
210 if (dtr < 0)
211 return -EIO;
212
213 /* dtr encodes adjustments of {-60,-40,-20,0,20,40,60} ppm */
214 dtr = ((dtr & 0x3) * 20) * (dtr & (1 << 2) ? -1 : 1);
215
216 return dtr + 100;
217 }
218
219 static int
220 isl1208_i2c_get_usr(struct i2c_client *client)
221 {
222 u8 buf[ISL1208_USR_SECTION_LEN] = { 0, };
223 int ret;
224
225 ret = isl1208_i2c_read_regs(client, ISL1208_REG_USR1, buf,
226 ISL1208_USR_SECTION_LEN);
227 if (ret < 0)
228 return ret;
229
230 return (buf[1] << 8) | buf[0];
231 }
232
233 static int
234 isl1208_i2c_set_usr(struct i2c_client *client, u16 usr)
235 {
236 u8 buf[ISL1208_USR_SECTION_LEN];
237
238 buf[0] = usr & 0xff;
239 buf[1] = (usr >> 8) & 0xff;
240
241 return isl1208_i2c_set_regs(client, ISL1208_REG_USR1, buf,
242 ISL1208_USR_SECTION_LEN);
243 }
244
245 static int
246 isl1208_rtc_toggle_alarm(struct i2c_client *client, int enable)
247 {
248 int icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT);
249
250 if (icr < 0) {
251 dev_err(&client->dev, "%s: reading INT failed\n", __func__);
252 return icr;
253 }
254
255 if (enable)
256 icr |= ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM;
257 else
258 icr &= ~(ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM);
259
260 icr = i2c_smbus_write_byte_data(client, ISL1208_REG_INT, icr);
261 if (icr < 0) {
262 dev_err(&client->dev, "%s: writing INT failed\n", __func__);
263 return icr;
264 }
265
266 return 0;
267 }
268
269 static int
270 isl1208_rtc_proc(struct device *dev, struct seq_file *seq)
271 {
272 struct i2c_client *const client = to_i2c_client(dev);
273 int sr, dtr, atr, usr;
274
275 sr = isl1208_i2c_get_sr(client);
276 if (sr < 0) {
277 dev_err(&client->dev, "%s: reading SR failed\n", __func__);
278 return sr;
279 }
280
281 seq_printf(seq, "status_reg\t:%s%s%s%s%s%s (0x%.2x)\n",
282 (sr & ISL1208_REG_SR_RTCF) ? " RTCF" : "",
283 (sr & ISL1208_REG_SR_BAT) ? " BAT" : "",
284 (sr & ISL1208_REG_SR_ALM) ? " ALM" : "",
285 (sr & ISL1208_REG_SR_WRTC) ? " WRTC" : "",
286 (sr & ISL1208_REG_SR_XTOSCB) ? " XTOSCB" : "",
287 (sr & ISL1208_REG_SR_ARST) ? " ARST" : "", sr);
288
289 seq_printf(seq, "batt_status\t: %s\n",
290 (sr & ISL1208_REG_SR_RTCF) ? "bad" : "okay");
291
292 dtr = isl1208_i2c_get_dtr(client);
293 if (dtr >= 0)
294 seq_printf(seq, "digital_trim\t: %d ppm\n", dtr - 100);
295
296 atr = isl1208_i2c_get_atr(client);
297 if (atr >= 0)
298 seq_printf(seq, "analog_trim\t: %d.%.2d pF\n",
299 atr >> 2, (atr & 0x3) * 25);
300
301 usr = isl1208_i2c_get_usr(client);
302 if (usr >= 0)
303 seq_printf(seq, "user_data\t: 0x%.4x\n", usr);
304
305 return 0;
306 }
307
308 static int
309 isl1208_i2c_read_time(struct i2c_client *client, struct rtc_time *tm)
310 {
311 int sr;
312 u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };
313
314 sr = isl1208_i2c_get_sr(client);
315 if (sr < 0) {
316 dev_err(&client->dev, "%s: reading SR failed\n", __func__);
317 return -EIO;
318 }
319
320 sr = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN);
321 if (sr < 0) {
322 dev_err(&client->dev, "%s: reading RTC section failed\n",
323 __func__);
324 return sr;
325 }
326
327 tm->tm_sec = bcd2bin(regs[ISL1208_REG_SC]);
328 tm->tm_min = bcd2bin(regs[ISL1208_REG_MN]);
329
330 /* HR field has a more complex interpretation */
331 {
332 const u8 _hr = regs[ISL1208_REG_HR];
333 if (_hr & ISL1208_REG_HR_MIL) /* 24h format */
334 tm->tm_hour = bcd2bin(_hr & 0x3f);
335 else {
336 /* 12h format */
337 tm->tm_hour = bcd2bin(_hr & 0x1f);
338 if (_hr & ISL1208_REG_HR_PM) /* PM flag set */
339 tm->tm_hour += 12;
340 }
341 }
342
343 tm->tm_mday = bcd2bin(regs[ISL1208_REG_DT]);
344 tm->tm_mon = bcd2bin(regs[ISL1208_REG_MO]) - 1; /* rtc starts at 1 */
345 tm->tm_year = bcd2bin(regs[ISL1208_REG_YR]) + 100;
346 tm->tm_wday = bcd2bin(regs[ISL1208_REG_DW]);
347
348 return 0;
349 }
350
351 static int
352 isl1208_i2c_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm)
353 {
354 struct rtc_time *const tm = &alarm->time;
355 u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, };
356 int icr, yr, sr = isl1208_i2c_get_sr(client);
357
358 if (sr < 0) {
359 dev_err(&client->dev, "%s: reading SR failed\n", __func__);
360 return sr;
361 }
362
363 sr = isl1208_i2c_read_regs(client, ISL1208_REG_SCA, regs,
364 ISL1208_ALARM_SECTION_LEN);
365 if (sr < 0) {
366 dev_err(&client->dev, "%s: reading alarm section failed\n",
367 __func__);
368 return sr;
369 }
370
371 /* MSB of each alarm register is an enable bit */
372 tm->tm_sec = bcd2bin(regs[ISL1208_REG_SCA - ISL1208_REG_SCA] & 0x7f);
373 tm->tm_min = bcd2bin(regs[ISL1208_REG_MNA - ISL1208_REG_SCA] & 0x7f);
374 tm->tm_hour = bcd2bin(regs[ISL1208_REG_HRA - ISL1208_REG_SCA] & 0x3f);
375 tm->tm_mday = bcd2bin(regs[ISL1208_REG_DTA - ISL1208_REG_SCA] & 0x3f);
376 tm->tm_mon =
377 bcd2bin(regs[ISL1208_REG_MOA - ISL1208_REG_SCA] & 0x1f) - 1;
378 tm->tm_wday = bcd2bin(regs[ISL1208_REG_DWA - ISL1208_REG_SCA] & 0x03);
379
380 /* The alarm doesn't store the year so get it from the rtc section */
381 yr = i2c_smbus_read_byte_data(client, ISL1208_REG_YR);
382 if (yr < 0) {
383 dev_err(&client->dev, "%s: reading RTC YR failed\n", __func__);
384 return yr;
385 }
386 tm->tm_year = bcd2bin(yr) + 100;
387
388 icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT);
389 if (icr < 0) {
390 dev_err(&client->dev, "%s: reading INT failed\n", __func__);
391 return icr;
392 }
393 alarm->enabled = !!(icr & ISL1208_REG_INT_ALME);
394
395 return 0;
396 }
397
398 static int
399 isl1208_i2c_set_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm)
400 {
401 struct rtc_time *alarm_tm = &alarm->time;
402 u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, };
403 const int offs = ISL1208_REG_SCA;
404 struct rtc_time rtc_tm;
405 int err, enable;
406
407 err = isl1208_i2c_read_time(client, &rtc_tm);
408 if (err)
409 return err;
410
411 /* If the alarm time is before the current time disable the alarm */
412 if (!alarm->enabled || rtc_tm_sub(alarm_tm, &rtc_tm) <= 0)
413 enable = 0x00;
414 else
415 enable = 0x80;
416
417 /* Program the alarm and enable it for each setting */
418 regs[ISL1208_REG_SCA - offs] = bin2bcd(alarm_tm->tm_sec) | enable;
419 regs[ISL1208_REG_MNA - offs] = bin2bcd(alarm_tm->tm_min) | enable;
420 regs[ISL1208_REG_HRA - offs] = bin2bcd(alarm_tm->tm_hour) |
421 ISL1208_REG_HR_MIL | enable;
422
423 regs[ISL1208_REG_DTA - offs] = bin2bcd(alarm_tm->tm_mday) | enable;
424 regs[ISL1208_REG_MOA - offs] = bin2bcd(alarm_tm->tm_mon + 1) | enable;
425 regs[ISL1208_REG_DWA - offs] = bin2bcd(alarm_tm->tm_wday & 7) | enable;
426
427 /* write ALARM registers */
428 err = isl1208_i2c_set_regs(client, offs, regs,
429 ISL1208_ALARM_SECTION_LEN);
430 if (err < 0) {
431 dev_err(&client->dev, "%s: writing ALARM section failed\n",
432 __func__);
433 return err;
434 }
435
436 err = isl1208_rtc_toggle_alarm(client, enable);
437 if (err)
438 return err;
439
440 return 0;
441 }
442
443 static int
444 isl1208_rtc_read_time(struct device *dev, struct rtc_time *tm)
445 {
446 return isl1208_i2c_read_time(to_i2c_client(dev), tm);
447 }
448
449 static int
450 isl1208_i2c_set_time(struct i2c_client *client, struct rtc_time const *tm)
451 {
452 int sr;
453 u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };
454
455 /* The clock has an 8 bit wide bcd-coded register (they never learn)
456 * for the year. tm_year is an offset from 1900 and we are interested
457 * in the 2000-2099 range, so any value less than 100 is invalid.
458 */
459 if (tm->tm_year < 100)
460 return -EINVAL;
461
462 regs[ISL1208_REG_SC] = bin2bcd(tm->tm_sec);
463 regs[ISL1208_REG_MN] = bin2bcd(tm->tm_min);
464 regs[ISL1208_REG_HR] = bin2bcd(tm->tm_hour) | ISL1208_REG_HR_MIL;
465
466 regs[ISL1208_REG_DT] = bin2bcd(tm->tm_mday);
467 regs[ISL1208_REG_MO] = bin2bcd(tm->tm_mon + 1);
468 regs[ISL1208_REG_YR] = bin2bcd(tm->tm_year - 100);
469
470 regs[ISL1208_REG_DW] = bin2bcd(tm->tm_wday & 7);
471
472 sr = isl1208_i2c_get_sr(client);
473 if (sr < 0) {
474 dev_err(&client->dev, "%s: reading SR failed\n", __func__);
475 return sr;
476 }
477
478 /* set WRTC */
479 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR,
480 sr | ISL1208_REG_SR_WRTC);
481 if (sr < 0) {
482 dev_err(&client->dev, "%s: writing SR failed\n", __func__);
483 return sr;
484 }
485
486 /* write RTC registers */
487 sr = isl1208_i2c_set_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN);
488 if (sr < 0) {
489 dev_err(&client->dev, "%s: writing RTC section failed\n",
490 __func__);
491 return sr;
492 }
493
494 /* clear WRTC again */
495 sr = isl1208_i2c_get_sr(client);
496 if (sr < 0) {
497 dev_err(&client->dev, "%s: reading SR failed\n", __func__);
498 return sr;
499 }
500 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR,
501 sr & ~ISL1208_REG_SR_WRTC);
502 if (sr < 0) {
503 dev_err(&client->dev, "%s: writing SR failed\n", __func__);
504 return sr;
505 }
506
507 return 0;
508 }
509
510
511 static int
512 isl1208_rtc_set_time(struct device *dev, struct rtc_time *tm)
513 {
514 return isl1208_i2c_set_time(to_i2c_client(dev), tm);
515 }
516
517 static int
518 isl1208_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
519 {
520 return isl1208_i2c_read_alarm(to_i2c_client(dev), alarm);
521 }
522
523 static int
524 isl1208_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
525 {
526 return isl1208_i2c_set_alarm(to_i2c_client(dev), alarm);
527 }
528
529 static ssize_t timestamp0_store(struct device *dev,
530 struct device_attribute *attr,
531 const char *buf, size_t count)
532 {
533 struct i2c_client *client = to_i2c_client(dev->parent);
534 int sr;
535
536 sr = isl1208_i2c_get_sr(client);
537 if (sr < 0) {
538 dev_err(dev, "%s: reading SR failed\n", __func__);
539 return sr;
540 }
541
542 sr &= ~ISL1208_REG_SR_EVT;
543
544 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr);
545 if (sr < 0)
546 dev_err(dev, "%s: writing SR failed\n",
547 __func__);
548
549 return count;
550 };
551
552 static ssize_t timestamp0_show(struct device *dev,
553 struct device_attribute *attr, char *buf)
554 {
555 struct i2c_client *client = to_i2c_client(dev->parent);
556 u8 regs[ISL1219_EVT_SECTION_LEN] = { 0, };
557 struct rtc_time tm;
558 int sr;
559
560 sr = isl1208_i2c_get_sr(client);
561 if (sr < 0) {
562 dev_err(dev, "%s: reading SR failed\n", __func__);
563 return sr;
564 }
565
566 if (!(sr & ISL1208_REG_SR_EVT))
567 return 0;
568
569 sr = isl1208_i2c_read_regs(client, ISL1219_REG_SCT, regs,
570 ISL1219_EVT_SECTION_LEN);
571 if (sr < 0) {
572 dev_err(dev, "%s: reading event section failed\n",
573 __func__);
574 return 0;
575 }
576
577 /* MSB of each alarm register is an enable bit */
578 tm.tm_sec = bcd2bin(regs[ISL1219_REG_SCT - ISL1219_REG_SCT] & 0x7f);
579 tm.tm_min = bcd2bin(regs[ISL1219_REG_MNT - ISL1219_REG_SCT] & 0x7f);
580 tm.tm_hour = bcd2bin(regs[ISL1219_REG_HRT - ISL1219_REG_SCT] & 0x3f);
581 tm.tm_mday = bcd2bin(regs[ISL1219_REG_DTT - ISL1219_REG_SCT] & 0x3f);
582 tm.tm_mon =
583 bcd2bin(regs[ISL1219_REG_MOT - ISL1219_REG_SCT] & 0x1f) - 1;
584 tm.tm_year = bcd2bin(regs[ISL1219_REG_YRT - ISL1219_REG_SCT]) + 100;
585
586 sr = rtc_valid_tm(&tm);
587 if (sr)
588 return sr;
589
590 return sprintf(buf, "%llu\n",
591 (unsigned long long)rtc_tm_to_time64(&tm));
592 };
593
594 static DEVICE_ATTR_RW(timestamp0);
595
596 static irqreturn_t
597 isl1208_rtc_interrupt(int irq, void *data)
598 {
599 unsigned long timeout = jiffies + msecs_to_jiffies(1000);
600 struct i2c_client *client = data;
601 struct isl1208_state *isl1208 = i2c_get_clientdata(client);
602 int handled = 0, sr, err;
603
604 /*
605 * I2C reads get NAK'ed if we read straight away after an interrupt?
606 * Using a mdelay/msleep didn't seem to help either, so we work around
607 * this by continually trying to read the register for a short time.
608 */
609 while (1) {
610 sr = isl1208_i2c_get_sr(client);
611 if (sr >= 0)
612 break;
613
614 if (time_after(jiffies, timeout)) {
615 dev_err(&client->dev, "%s: reading SR failed\n",
616 __func__);
617 return sr;
618 }
619 }
620
621 if (sr & ISL1208_REG_SR_ALM) {
622 dev_dbg(&client->dev, "alarm!\n");
623
624 rtc_update_irq(isl1208->rtc, 1, RTC_IRQF | RTC_AF);
625
626 /* Clear the alarm */
627 sr &= ~ISL1208_REG_SR_ALM;
628 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr);
629 if (sr < 0)
630 dev_err(&client->dev, "%s: writing SR failed\n",
631 __func__);
632 else
633 handled = 1;
634
635 /* Disable the alarm */
636 err = isl1208_rtc_toggle_alarm(client, 0);
637 if (err)
638 return err;
639 }
640
641 if (isl1208->config->has_tamper && (sr & ISL1208_REG_SR_EVT)) {
642 dev_warn(&client->dev, "event detected");
643 handled = 1;
644 if (isl1208->config->has_timestamp)
645 sysfs_notify(&isl1208->rtc->dev.kobj, NULL,
646 dev_attr_timestamp0.attr.name);
647 }
648
649 return handled ? IRQ_HANDLED : IRQ_NONE;
650 }
651
652 static const struct rtc_class_ops isl1208_rtc_ops = {
653 .proc = isl1208_rtc_proc,
654 .read_time = isl1208_rtc_read_time,
655 .set_time = isl1208_rtc_set_time,
656 .read_alarm = isl1208_rtc_read_alarm,
657 .set_alarm = isl1208_rtc_set_alarm,
658 };
659
660 /* sysfs interface */
661
662 static ssize_t
663 isl1208_sysfs_show_atrim(struct device *dev,
664 struct device_attribute *attr, char *buf)
665 {
666 int atr = isl1208_i2c_get_atr(to_i2c_client(dev->parent));
667 if (atr < 0)
668 return atr;
669
670 return sprintf(buf, "%d.%.2d pF\n", atr >> 2, (atr & 0x3) * 25);
671 }
672
673 static DEVICE_ATTR(atrim, S_IRUGO, isl1208_sysfs_show_atrim, NULL);
674
675 static ssize_t
676 isl1208_sysfs_show_dtrim(struct device *dev,
677 struct device_attribute *attr, char *buf)
678 {
679 int dtr = isl1208_i2c_get_dtr(to_i2c_client(dev->parent));
680 if (dtr < 0)
681 return dtr;
682
683 return sprintf(buf, "%d ppm\n", dtr - 100);
684 }
685
686 static DEVICE_ATTR(dtrim, S_IRUGO, isl1208_sysfs_show_dtrim, NULL);
687
688 static ssize_t
689 isl1208_sysfs_show_usr(struct device *dev,
690 struct device_attribute *attr, char *buf)
691 {
692 int usr = isl1208_i2c_get_usr(to_i2c_client(dev->parent));
693 if (usr < 0)
694 return usr;
695
696 return sprintf(buf, "0x%.4x\n", usr);
697 }
698
699 static ssize_t
700 isl1208_sysfs_store_usr(struct device *dev,
701 struct device_attribute *attr,
702 const char *buf, size_t count)
703 {
704 int usr = -1;
705
706 if (buf[0] == '0' && (buf[1] == 'x' || buf[1] == 'X')) {
707 if (sscanf(buf, "%x", &usr) != 1)
708 return -EINVAL;
709 } else {
710 if (sscanf(buf, "%d", &usr) != 1)
711 return -EINVAL;
712 }
713
714 if (usr < 0 || usr > 0xffff)
715 return -EINVAL;
716
717 if (isl1208_i2c_set_usr(to_i2c_client(dev->parent), usr))
718 return -EIO;
719
720 return count;
721 }
722
723 static DEVICE_ATTR(usr, S_IRUGO | S_IWUSR, isl1208_sysfs_show_usr,
724 isl1208_sysfs_store_usr);
725
726 static struct attribute *isl1208_rtc_attrs[] = {
727 &dev_attr_atrim.attr,
728 &dev_attr_dtrim.attr,
729 &dev_attr_usr.attr,
730 NULL
731 };
732
733 static const struct attribute_group isl1208_rtc_sysfs_files = {
734 .attrs = isl1208_rtc_attrs,
735 };
736
737 static struct attribute *isl1219_rtc_attrs[] = {
738 &dev_attr_timestamp0.attr,
739 NULL
740 };
741
742 static const struct attribute_group isl1219_rtc_sysfs_files = {
743 .attrs = isl1219_rtc_attrs,
744 };
745
746 static int isl1208_nvmem_read(void *priv, unsigned int off, void *buf,
747 size_t count)
748 {
749 struct isl1208_state *isl1208 = priv;
750 struct i2c_client *client = to_i2c_client(isl1208->rtc->dev.parent);
751 int ret;
752
753 /* nvmem sanitizes offset/count for us, but count==0 is possible */
754 if (!count)
755 return count;
756 ret = isl1208_i2c_read_regs(client, ISL1208_REG_USR1 + off, buf,
757 count);
758 return ret == 0 ? count : ret;
759 }
760
761 static int isl1208_nvmem_write(void *priv, unsigned int off, void *buf,
762 size_t count)
763 {
764 struct isl1208_state *isl1208 = priv;
765 struct i2c_client *client = to_i2c_client(isl1208->rtc->dev.parent);
766 int ret;
767
768 /* nvmem sanitizes off/count for us, but count==0 is possible */
769 if (!count)
770 return count;
771 ret = isl1208_i2c_set_regs(client, ISL1208_REG_USR1 + off, buf,
772 count);
773
774 return ret == 0 ? count : ret;
775 }
776
777 static const struct nvmem_config isl1208_nvmem_config = {
778 .name = "isl1208_nvram",
779 .word_size = 1,
780 .stride = 1,
781 /* .size from chip specific config */
782 .reg_read = isl1208_nvmem_read,
783 .reg_write = isl1208_nvmem_write,
784 };
785
786 static int isl1208_setup_irq(struct i2c_client *client, int irq)
787 {
788 int rc = devm_request_threaded_irq(&client->dev, irq, NULL,
789 isl1208_rtc_interrupt,
790 IRQF_SHARED | IRQF_ONESHOT,
791 isl1208_driver.driver.name,
792 client);
793 if (!rc) {
794 device_init_wakeup(&client->dev, 1);
795 enable_irq_wake(irq);
796 } else {
797 dev_err(&client->dev,
798 "Unable to request irq %d, no alarm support\n",
799 irq);
800 }
801 return rc;
802 }
803
804 static int
805 isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id)
806 {
807 int rc = 0;
808 struct isl1208_state *isl1208;
809 int evdet_irq = -1;
810
811 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
812 return -ENODEV;
813
814 if (isl1208_i2c_validate_client(client) < 0)
815 return -ENODEV;
816
817 /* Allocate driver state, point i2c client data to it */
818 isl1208 = devm_kzalloc(&client->dev, sizeof(*isl1208), GFP_KERNEL);
819 if (!isl1208)
820 return -ENOMEM;
821 i2c_set_clientdata(client, isl1208);
822
823 /* Determine which chip we have */
824 if (client->dev.of_node) {
825 isl1208->config = of_device_get_match_data(&client->dev);
826 if (!isl1208->config)
827 return -ENODEV;
828 } else {
829 if (id->driver_data >= ISL_LAST_ID)
830 return -ENODEV;
831 isl1208->config = &isl1208_configs[id->driver_data];
832 }
833
834 isl1208->rtc = devm_rtc_allocate_device(&client->dev);
835 if (IS_ERR(isl1208->rtc))
836 return PTR_ERR(isl1208->rtc);
837
838 isl1208->rtc->ops = &isl1208_rtc_ops;
839
840 /* Setup nvmem configuration in driver state struct */
841 isl1208->nvmem_config = isl1208_nvmem_config;
842 isl1208->nvmem_config.size = isl1208->config->nvmem_length;
843 isl1208->nvmem_config.priv = isl1208;
844
845 rc = isl1208_i2c_get_sr(client);
846 if (rc < 0) {
847 dev_err(&client->dev, "reading status failed\n");
848 return rc;
849 }
850
851 if (rc & ISL1208_REG_SR_RTCF)
852 dev_warn(&client->dev, "rtc power failure detected, "
853 "please set clock.\n");
854
855 if (isl1208->config->has_tamper) {
856 struct device_node *np = client->dev.of_node;
857 u32 evienb;
858
859 rc = i2c_smbus_read_byte_data(client, ISL1219_REG_EV);
860 if (rc < 0) {
861 dev_err(&client->dev, "failed to read EV reg\n");
862 return rc;
863 }
864 rc |= ISL1219_REG_EV_EVEN;
865 if (!of_property_read_u32(np, "isil,ev-evienb", &evienb)) {
866 if (evienb)
867 rc |= ISL1219_REG_EV_EVIENB;
868 else
869 rc &= ~ISL1219_REG_EV_EVIENB;
870 }
871 rc = i2c_smbus_write_byte_data(client, ISL1219_REG_EV, rc);
872 if (rc < 0) {
873 dev_err(&client->dev, "could not enable tamper detection\n");
874 return rc;
875 }
876 evdet_irq = of_irq_get_byname(np, "evdet");
877 }
878 if (isl1208->config->has_timestamp) {
879 rc = rtc_add_group(isl1208->rtc, &isl1219_rtc_sysfs_files);
880 if (rc)
881 return rc;
882 }
883
884 rc = rtc_add_group(isl1208->rtc, &isl1208_rtc_sysfs_files);
885 if (rc)
886 return rc;
887
888 if (client->irq > 0)
889 rc = isl1208_setup_irq(client, client->irq);
890 if (rc)
891 return rc;
892
893 if (evdet_irq > 0 && evdet_irq != client->irq)
894 rc = isl1208_setup_irq(client, evdet_irq);
895 if (rc)
896 return rc;
897
898 rc = rtc_nvmem_register(isl1208->rtc, &isl1208->nvmem_config);
899 if (rc)
900 return rc;
901
902 return rtc_register_device(isl1208->rtc);
903 }
904
905 static struct i2c_driver isl1208_driver = {
906 .driver = {
907 .name = "rtc-isl1208",
908 .of_match_table = of_match_ptr(isl1208_of_match),
909 },
910 .probe = isl1208_probe,
911 .id_table = isl1208_id,
912 };
913
914 module_i2c_driver(isl1208_driver);
915
916 MODULE_AUTHOR("Herbert Valerio Riedel <hvr@gnu.org>");
917 MODULE_DESCRIPTION("Intersil ISL1208 RTC driver");
918 MODULE_LICENSE("GPL");
Linux with added FPC-III support