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/module.h>
14 #include <linux/i2c.h>
15 #include <linux/bcd.h>
16 #include <linux/rtc.h>
17
18 #define DRV_VERSION "0.3"
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_ALM (1<<2) /* alarm */
39 #define ISL1208_REG_SR_BAT (1<<1) /* battery */
40 #define ISL1208_REG_SR_RTCF (1<<0) /* rtc fail */
41 #define ISL1208_REG_INT 0x08
42 #define ISL1208_REG_INT_ALME (1<<6) /* alarm enable */
43 #define ISL1208_REG_INT_IM (1<<7) /* interrupt/alarm mode */
44 #define ISL1208_REG_09 0x09 /* reserved */
45 #define ISL1208_REG_ATR 0x0a
46 #define ISL1208_REG_DTR 0x0b
47
48 /* alarm section */
49 #define ISL1208_REG_SCA 0x0c
50 #define ISL1208_REG_MNA 0x0d
51 #define ISL1208_REG_HRA 0x0e
52 #define ISL1208_REG_DTA 0x0f
53 #define ISL1208_REG_MOA 0x10
54 #define ISL1208_REG_DWA 0x11
55 #define ISL1208_ALARM_SECTION_LEN 6
56
57 /* user section */
58 #define ISL1208_REG_USR1 0x12
59 #define ISL1208_REG_USR2 0x13
60 #define ISL1208_USR_SECTION_LEN 2
61
62 static struct i2c_driver isl1208_driver;
63
64 /* block read */
65 static int
isl1208_i2c_read_regs(struct i2c_client * client,u8 reg,u8 buf[],unsigned len)66 isl1208_i2c_read_regs(struct i2c_client *client, u8 reg, u8 buf[],
67 unsigned len)
68 {
69 u8 reg_addr[1] = { reg };
70 struct i2c_msg msgs[2] = {
71 {client->addr, 0, sizeof(reg_addr), reg_addr}
72 ,
73 {client->addr, I2C_M_RD, len, buf}
74 };
75 int ret;
76
77 BUG_ON(reg > ISL1208_REG_USR2);
78 BUG_ON(reg + len > ISL1208_REG_USR2 + 1);
79
80 ret = i2c_transfer(client->adapter, msgs, 2);
81 if (ret > 0)
82 ret = 0;
83 return ret;
84 }
85
86 /* block write */
87 static int
isl1208_i2c_set_regs(struct i2c_client * client,u8 reg,u8 const buf[],unsigned len)88 isl1208_i2c_set_regs(struct i2c_client *client, u8 reg, u8 const buf[],
89 unsigned len)
90 {
91 u8 i2c_buf[ISL1208_REG_USR2 + 2];
92 struct i2c_msg msgs[1] = {
93 {client->addr, 0, len + 1, i2c_buf}
94 };
95 int ret;
96
97 BUG_ON(reg > ISL1208_REG_USR2);
98 BUG_ON(reg + len > ISL1208_REG_USR2 + 1);
99
100 i2c_buf[0] = reg;
101 memcpy(&i2c_buf[1], &buf[0], len);
102
103 ret = i2c_transfer(client->adapter, msgs, 1);
104 if (ret > 0)
105 ret = 0;
106 return ret;
107 }
108
109 /* simple check to see wether we have a isl1208 */
110 static int
isl1208_i2c_validate_client(struct i2c_client * client)111 isl1208_i2c_validate_client(struct i2c_client *client)
112 {
113 u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };
114 u8 zero_mask[ISL1208_RTC_SECTION_LEN] = {
115 0x80, 0x80, 0x40, 0xc0, 0xe0, 0x00, 0xf8
116 };
117 int i;
118 int ret;
119
120 ret = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN);
121 if (ret < 0)
122 return ret;
123
124 for (i = 0; i < ISL1208_RTC_SECTION_LEN; ++i) {
125 if (regs[i] & zero_mask[i]) /* check if bits are cleared */
126 return -ENODEV;
127 }
128
129 return 0;
130 }
131
132 static int
isl1208_i2c_get_sr(struct i2c_client * client)133 isl1208_i2c_get_sr(struct i2c_client *client)
134 {
135 int sr = i2c_smbus_read_byte_data(client, ISL1208_REG_SR);
136 if (sr < 0)
137 return -EIO;
138
139 return sr;
140 }
141
142 static int
isl1208_i2c_get_atr(struct i2c_client * client)143 isl1208_i2c_get_atr(struct i2c_client *client)
144 {
145 int atr = i2c_smbus_read_byte_data(client, ISL1208_REG_ATR);
146 if (atr < 0)
147 return atr;
148
149 /* The 6bit value in the ATR register controls the load
150 * capacitance C_load * in steps of 0.25pF
151 *
152 * bit (1<<5) of the ATR register is inverted
153 *
154 * C_load(ATR=0x20) = 4.50pF
155 * C_load(ATR=0x00) = 12.50pF
156 * C_load(ATR=0x1f) = 20.25pF
157 *
158 */
159
160 atr &= 0x3f; /* mask out lsb */
161 atr ^= 1 << 5; /* invert 6th bit */
162 atr += 2 * 9; /* add offset of 4.5pF; unit[atr] = 0.25pF */
163
164 return atr;
165 }
166
167 static int
isl1208_i2c_get_dtr(struct i2c_client * client)168 isl1208_i2c_get_dtr(struct i2c_client *client)
169 {
170 int dtr = i2c_smbus_read_byte_data(client, ISL1208_REG_DTR);
171 if (dtr < 0)
172 return -EIO;
173
174 /* dtr encodes adjustments of {-60,-40,-20,0,20,40,60} ppm */
175 dtr = ((dtr & 0x3) * 20) * (dtr & (1 << 2) ? -1 : 1);
176
177 return dtr;
178 }
179
180 static int
isl1208_i2c_get_usr(struct i2c_client * client)181 isl1208_i2c_get_usr(struct i2c_client *client)
182 {
183 u8 buf[ISL1208_USR_SECTION_LEN] = { 0, };
184 int ret;
185
186 ret = isl1208_i2c_read_regs(client, ISL1208_REG_USR1, buf,
187 ISL1208_USR_SECTION_LEN);
188 if (ret < 0)
189 return ret;
190
191 return (buf[1] << 8) | buf[0];
192 }
193
194 static int
isl1208_i2c_set_usr(struct i2c_client * client,u16 usr)195 isl1208_i2c_set_usr(struct i2c_client *client, u16 usr)
196 {
197 u8 buf[ISL1208_USR_SECTION_LEN];
198
199 buf[0] = usr & 0xff;
200 buf[1] = (usr >> 8) & 0xff;
201
202 return isl1208_i2c_set_regs(client, ISL1208_REG_USR1, buf,
203 ISL1208_USR_SECTION_LEN);
204 }
205
206 static int
isl1208_rtc_toggle_alarm(struct i2c_client * client,int enable)207 isl1208_rtc_toggle_alarm(struct i2c_client *client, int enable)
208 {
209 int icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT);
210
211 if (icr < 0) {
212 dev_err(&client->dev, "%s: reading INT failed\n", __func__);
213 return icr;
214 }
215
216 if (enable)
217 icr |= ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM;
218 else
219 icr &= ~(ISL1208_REG_INT_ALME | ISL1208_REG_INT_IM);
220
221 icr = i2c_smbus_write_byte_data(client, ISL1208_REG_INT, icr);
222 if (icr < 0) {
223 dev_err(&client->dev, "%s: writing INT failed\n", __func__);
224 return icr;
225 }
226
227 return 0;
228 }
229
230 static int
isl1208_rtc_proc(struct device * dev,struct seq_file * seq)231 isl1208_rtc_proc(struct device *dev, struct seq_file *seq)
232 {
233 struct i2c_client *const client = to_i2c_client(dev);
234 int sr, dtr, atr, usr;
235
236 sr = isl1208_i2c_get_sr(client);
237 if (sr < 0) {
238 dev_err(&client->dev, "%s: reading SR failed\n", __func__);
239 return sr;
240 }
241
242 seq_printf(seq, "status_reg\t:%s%s%s%s%s%s (0x%.2x)\n",
243 (sr & ISL1208_REG_SR_RTCF) ? " RTCF" : "",
244 (sr & ISL1208_REG_SR_BAT) ? " BAT" : "",
245 (sr & ISL1208_REG_SR_ALM) ? " ALM" : "",
246 (sr & ISL1208_REG_SR_WRTC) ? " WRTC" : "",
247 (sr & ISL1208_REG_SR_XTOSCB) ? " XTOSCB" : "",
248 (sr & ISL1208_REG_SR_ARST) ? " ARST" : "", sr);
249
250 seq_printf(seq, "batt_status\t: %s\n",
251 (sr & ISL1208_REG_SR_RTCF) ? "bad" : "okay");
252
253 dtr = isl1208_i2c_get_dtr(client);
254 if (dtr >= 0 - 1)
255 seq_printf(seq, "digital_trim\t: %d ppm\n", dtr);
256
257 atr = isl1208_i2c_get_atr(client);
258 if (atr >= 0)
259 seq_printf(seq, "analog_trim\t: %d.%.2d pF\n",
260 atr >> 2, (atr & 0x3) * 25);
261
262 usr = isl1208_i2c_get_usr(client);
263 if (usr >= 0)
264 seq_printf(seq, "user_data\t: 0x%.4x\n", usr);
265
266 return 0;
267 }
268
269 static int
isl1208_i2c_read_time(struct i2c_client * client,struct rtc_time * tm)270 isl1208_i2c_read_time(struct i2c_client *client, struct rtc_time *tm)
271 {
272 int sr;
273 u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };
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 -EIO;
279 }
280
281 sr = isl1208_i2c_read_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN);
282 if (sr < 0) {
283 dev_err(&client->dev, "%s: reading RTC section failed\n",
284 __func__);
285 return sr;
286 }
287
288 tm->tm_sec = bcd2bin(regs[ISL1208_REG_SC]);
289 tm->tm_min = bcd2bin(regs[ISL1208_REG_MN]);
290
291 /* HR field has a more complex interpretation */
292 {
293 const u8 _hr = regs[ISL1208_REG_HR];
294 if (_hr & ISL1208_REG_HR_MIL) /* 24h format */
295 tm->tm_hour = bcd2bin(_hr & 0x3f);
296 else {
297 /* 12h format */
298 tm->tm_hour = bcd2bin(_hr & 0x1f);
299 if (_hr & ISL1208_REG_HR_PM) /* PM flag set */
300 tm->tm_hour += 12;
301 }
302 }
303
304 tm->tm_mday = bcd2bin(regs[ISL1208_REG_DT]);
305 tm->tm_mon = bcd2bin(regs[ISL1208_REG_MO]) - 1; /* rtc starts at 1 */
306 tm->tm_year = bcd2bin(regs[ISL1208_REG_YR]) + 100;
307 tm->tm_wday = bcd2bin(regs[ISL1208_REG_DW]);
308
309 return 0;
310 }
311
312 static int
isl1208_i2c_read_alarm(struct i2c_client * client,struct rtc_wkalrm * alarm)313 isl1208_i2c_read_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm)
314 {
315 struct rtc_time *const tm = &alarm->time;
316 u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, };
317 int icr, yr, sr = isl1208_i2c_get_sr(client);
318
319 if (sr < 0) {
320 dev_err(&client->dev, "%s: reading SR failed\n", __func__);
321 return sr;
322 }
323
324 sr = isl1208_i2c_read_regs(client, ISL1208_REG_SCA, regs,
325 ISL1208_ALARM_SECTION_LEN);
326 if (sr < 0) {
327 dev_err(&client->dev, "%s: reading alarm section failed\n",
328 __func__);
329 return sr;
330 }
331
332 /* MSB of each alarm register is an enable bit */
333 tm->tm_sec = bcd2bin(regs[ISL1208_REG_SCA - ISL1208_REG_SCA] & 0x7f);
334 tm->tm_min = bcd2bin(regs[ISL1208_REG_MNA - ISL1208_REG_SCA] & 0x7f);
335 tm->tm_hour = bcd2bin(regs[ISL1208_REG_HRA - ISL1208_REG_SCA] & 0x3f);
336 tm->tm_mday = bcd2bin(regs[ISL1208_REG_DTA - ISL1208_REG_SCA] & 0x3f);
337 tm->tm_mon =
338 bcd2bin(regs[ISL1208_REG_MOA - ISL1208_REG_SCA] & 0x1f) - 1;
339 tm->tm_wday = bcd2bin(regs[ISL1208_REG_DWA - ISL1208_REG_SCA] & 0x03);
340
341 /* The alarm doesn't store the year so get it from the rtc section */
342 yr = i2c_smbus_read_byte_data(client, ISL1208_REG_YR);
343 if (yr < 0) {
344 dev_err(&client->dev, "%s: reading RTC YR failed\n", __func__);
345 return yr;
346 }
347 tm->tm_year = bcd2bin(yr) + 100;
348
349 icr = i2c_smbus_read_byte_data(client, ISL1208_REG_INT);
350 if (icr < 0) {
351 dev_err(&client->dev, "%s: reading INT failed\n", __func__);
352 return icr;
353 }
354 alarm->enabled = !!(icr & ISL1208_REG_INT_ALME);
355
356 return 0;
357 }
358
359 static int
isl1208_i2c_set_alarm(struct i2c_client * client,struct rtc_wkalrm * alarm)360 isl1208_i2c_set_alarm(struct i2c_client *client, struct rtc_wkalrm *alarm)
361 {
362 struct rtc_time *alarm_tm = &alarm->time;
363 u8 regs[ISL1208_ALARM_SECTION_LEN] = { 0, };
364 const int offs = ISL1208_REG_SCA;
365 unsigned long rtc_secs, alarm_secs;
366 struct rtc_time rtc_tm;
367 int err, enable;
368
369 err = isl1208_i2c_read_time(client, &rtc_tm);
370 if (err)
371 return err;
372 err = rtc_tm_to_time(&rtc_tm, &rtc_secs);
373 if (err)
374 return err;
375 err = rtc_tm_to_time(alarm_tm, &alarm_secs);
376 if (err)
377 return err;
378
379 /* If the alarm time is before the current time disable the alarm */
380 if (!alarm->enabled || alarm_secs <= rtc_secs)
381 enable = 0x00;
382 else
383 enable = 0x80;
384
385 /* Program the alarm and enable it for each setting */
386 regs[ISL1208_REG_SCA - offs] = bin2bcd(alarm_tm->tm_sec) | enable;
387 regs[ISL1208_REG_MNA - offs] = bin2bcd(alarm_tm->tm_min) | enable;
388 regs[ISL1208_REG_HRA - offs] = bin2bcd(alarm_tm->tm_hour) |
389 ISL1208_REG_HR_MIL | enable;
390
391 regs[ISL1208_REG_DTA - offs] = bin2bcd(alarm_tm->tm_mday) | enable;
392 regs[ISL1208_REG_MOA - offs] = bin2bcd(alarm_tm->tm_mon + 1) | enable;
393 regs[ISL1208_REG_DWA - offs] = bin2bcd(alarm_tm->tm_wday & 7) | enable;
394
395 /* write ALARM registers */
396 err = isl1208_i2c_set_regs(client, offs, regs,
397 ISL1208_ALARM_SECTION_LEN);
398 if (err < 0) {
399 dev_err(&client->dev, "%s: writing ALARM section failed\n",
400 __func__);
401 return err;
402 }
403
404 err = isl1208_rtc_toggle_alarm(client, enable);
405 if (err)
406 return err;
407
408 return 0;
409 }
410
411 static int
isl1208_rtc_read_time(struct device * dev,struct rtc_time * tm)412 isl1208_rtc_read_time(struct device *dev, struct rtc_time *tm)
413 {
414 return isl1208_i2c_read_time(to_i2c_client(dev), tm);
415 }
416
417 static int
isl1208_i2c_set_time(struct i2c_client * client,struct rtc_time const * tm)418 isl1208_i2c_set_time(struct i2c_client *client, struct rtc_time const *tm)
419 {
420 int sr;
421 u8 regs[ISL1208_RTC_SECTION_LEN] = { 0, };
422
423 /* The clock has an 8 bit wide bcd-coded register (they never learn)
424 * for the year. tm_year is an offset from 1900 and we are interested
425 * in the 2000-2099 range, so any value less than 100 is invalid.
426 */
427 if (tm->tm_year < 100)
428 return -EINVAL;
429
430 regs[ISL1208_REG_SC] = bin2bcd(tm->tm_sec);
431 regs[ISL1208_REG_MN] = bin2bcd(tm->tm_min);
432 regs[ISL1208_REG_HR] = bin2bcd(tm->tm_hour) | ISL1208_REG_HR_MIL;
433
434 regs[ISL1208_REG_DT] = bin2bcd(tm->tm_mday);
435 regs[ISL1208_REG_MO] = bin2bcd(tm->tm_mon + 1);
436 regs[ISL1208_REG_YR] = bin2bcd(tm->tm_year - 100);
437
438 regs[ISL1208_REG_DW] = bin2bcd(tm->tm_wday & 7);
439
440 sr = isl1208_i2c_get_sr(client);
441 if (sr < 0) {
442 dev_err(&client->dev, "%s: reading SR failed\n", __func__);
443 return sr;
444 }
445
446 /* set WRTC */
447 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR,
448 sr | ISL1208_REG_SR_WRTC);
449 if (sr < 0) {
450 dev_err(&client->dev, "%s: writing SR failed\n", __func__);
451 return sr;
452 }
453
454 /* write RTC registers */
455 sr = isl1208_i2c_set_regs(client, 0, regs, ISL1208_RTC_SECTION_LEN);
456 if (sr < 0) {
457 dev_err(&client->dev, "%s: writing RTC section failed\n",
458 __func__);
459 return sr;
460 }
461
462 /* clear WRTC again */
463 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR,
464 sr & ~ISL1208_REG_SR_WRTC);
465 if (sr < 0) {
466 dev_err(&client->dev, "%s: writing SR failed\n", __func__);
467 return sr;
468 }
469
470 return 0;
471 }
472
473
474 static int
isl1208_rtc_set_time(struct device * dev,struct rtc_time * tm)475 isl1208_rtc_set_time(struct device *dev, struct rtc_time *tm)
476 {
477 return isl1208_i2c_set_time(to_i2c_client(dev), tm);
478 }
479
480 static int
isl1208_rtc_read_alarm(struct device * dev,struct rtc_wkalrm * alarm)481 isl1208_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
482 {
483 return isl1208_i2c_read_alarm(to_i2c_client(dev), alarm);
484 }
485
486 static int
isl1208_rtc_set_alarm(struct device * dev,struct rtc_wkalrm * alarm)487 isl1208_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
488 {
489 return isl1208_i2c_set_alarm(to_i2c_client(dev), alarm);
490 }
491
492 static irqreturn_t
isl1208_rtc_interrupt(int irq,void * data)493 isl1208_rtc_interrupt(int irq, void *data)
494 {
495 unsigned long timeout = jiffies + msecs_to_jiffies(1000);
496 struct i2c_client *client = data;
497 struct rtc_device *rtc = i2c_get_clientdata(client);
498 int handled = 0, sr, err;
499
500 /*
501 * I2C reads get NAK'ed if we read straight away after an interrupt?
502 * Using a mdelay/msleep didn't seem to help either, so we work around
503 * this by continually trying to read the register for a short time.
504 */
505 while (1) {
506 sr = isl1208_i2c_get_sr(client);
507 if (sr >= 0)
508 break;
509
510 if (time_after(jiffies, timeout)) {
511 dev_err(&client->dev, "%s: reading SR failed\n",
512 __func__);
513 return sr;
514 }
515 }
516
517 if (sr & ISL1208_REG_SR_ALM) {
518 dev_dbg(&client->dev, "alarm!\n");
519
520 rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF);
521
522 /* Clear the alarm */
523 sr &= ~ISL1208_REG_SR_ALM;
524 sr = i2c_smbus_write_byte_data(client, ISL1208_REG_SR, sr);
525 if (sr < 0)
526 dev_err(&client->dev, "%s: writing SR failed\n",
527 __func__);
528 else
529 handled = 1;
530
531 /* Disable the alarm */
532 err = isl1208_rtc_toggle_alarm(client, 0);
533 if (err)
534 return err;
535 }
536
537 return handled ? IRQ_HANDLED : IRQ_NONE;
538 }
539
540 static const struct rtc_class_ops isl1208_rtc_ops = {
541 .proc = isl1208_rtc_proc,
542 .read_time = isl1208_rtc_read_time,
543 .set_time = isl1208_rtc_set_time,
544 .read_alarm = isl1208_rtc_read_alarm,
545 .set_alarm = isl1208_rtc_set_alarm,
546 };
547
548 /* sysfs interface */
549
550 static ssize_t
isl1208_sysfs_show_atrim(struct device * dev,struct device_attribute * attr,char * buf)551 isl1208_sysfs_show_atrim(struct device *dev,
552 struct device_attribute *attr, char *buf)
553 {
554 int atr = isl1208_i2c_get_atr(to_i2c_client(dev));
555 if (atr < 0)
556 return atr;
557
558 return sprintf(buf, "%d.%.2d pF\n", atr >> 2, (atr & 0x3) * 25);
559 }
560
561 static DEVICE_ATTR(atrim, S_IRUGO, isl1208_sysfs_show_atrim, NULL);
562
563 static ssize_t
isl1208_sysfs_show_dtrim(struct device * dev,struct device_attribute * attr,char * buf)564 isl1208_sysfs_show_dtrim(struct device *dev,
565 struct device_attribute *attr, char *buf)
566 {
567 int dtr = isl1208_i2c_get_dtr(to_i2c_client(dev));
568 if (dtr < 0)
569 return dtr;
570
571 return sprintf(buf, "%d ppm\n", dtr);
572 }
573
574 static DEVICE_ATTR(dtrim, S_IRUGO, isl1208_sysfs_show_dtrim, NULL);
575
576 static ssize_t
isl1208_sysfs_show_usr(struct device * dev,struct device_attribute * attr,char * buf)577 isl1208_sysfs_show_usr(struct device *dev,
578 struct device_attribute *attr, char *buf)
579 {
580 int usr = isl1208_i2c_get_usr(to_i2c_client(dev));
581 if (usr < 0)
582 return usr;
583
584 return sprintf(buf, "0x%.4x\n", usr);
585 }
586
587 static ssize_t
isl1208_sysfs_store_usr(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)588 isl1208_sysfs_store_usr(struct device *dev,
589 struct device_attribute *attr,
590 const char *buf, size_t count)
591 {
592 int usr = -1;
593
594 if (buf[0] == '0' && (buf[1] == 'x' || buf[1] == 'X')) {
595 if (sscanf(buf, "%x", &usr) != 1)
596 return -EINVAL;
597 } else {
598 if (sscanf(buf, "%d", &usr) != 1)
599 return -EINVAL;
600 }
601
602 if (usr < 0 || usr > 0xffff)
603 return -EINVAL;
604
605 return isl1208_i2c_set_usr(to_i2c_client(dev), usr) ? -EIO : count;
606 }
607
608 static DEVICE_ATTR(usr, S_IRUGO | S_IWUSR, isl1208_sysfs_show_usr,
609 isl1208_sysfs_store_usr);
610
611 static struct attribute *isl1208_rtc_attrs[] = {
612 &dev_attr_atrim.attr,
613 &dev_attr_dtrim.attr,
614 &dev_attr_usr.attr,
615 NULL
616 };
617
618 static const struct attribute_group isl1208_rtc_sysfs_files = {
619 .attrs = isl1208_rtc_attrs,
620 };
621
622 static int
isl1208_probe(struct i2c_client * client,const struct i2c_device_id * id)623 isl1208_probe(struct i2c_client *client, const struct i2c_device_id *id)
624 {
625 int rc = 0;
626 struct rtc_device *rtc;
627
628 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
629 return -ENODEV;
630
631 if (isl1208_i2c_validate_client(client) < 0)
632 return -ENODEV;
633
634 dev_info(&client->dev,
635 "chip found, driver version " DRV_VERSION "\n");
636
637 if (client->irq > 0) {
638 rc = request_threaded_irq(client->irq, NULL,
639 isl1208_rtc_interrupt,
640 IRQF_SHARED,
641 isl1208_driver.driver.name, client);
642 if (!rc) {
643 device_init_wakeup(&client->dev, 1);
644 enable_irq_wake(client->irq);
645 } else {
646 dev_err(&client->dev,
647 "Unable to request irq %d, no alarm support\n",
648 client->irq);
649 client->irq = 0;
650 }
651 }
652
653 rtc = rtc_device_register(isl1208_driver.driver.name,
654 &client->dev, &isl1208_rtc_ops,
655 THIS_MODULE);
656 if (IS_ERR(rtc)) {
657 rc = PTR_ERR(rtc);
658 goto exit_free_irq;
659 }
660
661 i2c_set_clientdata(client, rtc);
662
663 rc = isl1208_i2c_get_sr(client);
664 if (rc < 0) {
665 dev_err(&client->dev, "reading status failed\n");
666 goto exit_unregister;
667 }
668
669 if (rc & ISL1208_REG_SR_RTCF)
670 dev_warn(&client->dev, "rtc power failure detected, "
671 "please set clock.\n");
672
673 rc = sysfs_create_group(&client->dev.kobj, &isl1208_rtc_sysfs_files);
674 if (rc)
675 goto exit_unregister;
676
677 return 0;
678
679 exit_unregister:
680 rtc_device_unregister(rtc);
681 exit_free_irq:
682 if (client->irq)
683 free_irq(client->irq, client);
684
685 return rc;
686 }
687
688 static int
isl1208_remove(struct i2c_client * client)689 isl1208_remove(struct i2c_client *client)
690 {
691 struct rtc_device *rtc = i2c_get_clientdata(client);
692
693 sysfs_remove_group(&client->dev.kobj, &isl1208_rtc_sysfs_files);
694 rtc_device_unregister(rtc);
695 if (client->irq)
696 free_irq(client->irq, client);
697
698 return 0;
699 }
700
701 static const struct i2c_device_id isl1208_id[] = {
702 { "isl1208", 0 },
703 { }
704 };
705 MODULE_DEVICE_TABLE(i2c, isl1208_id);
706
707 static struct i2c_driver isl1208_driver = {
708 .driver = {
709 .name = "rtc-isl1208",
710 },
711 .probe = isl1208_probe,
712 .remove = isl1208_remove,
713 .id_table = isl1208_id,
714 };
715
716 module_i2c_driver(isl1208_driver);
717
718 MODULE_AUTHOR("Herbert Valerio Riedel <hvr@gnu.org>");
719 MODULE_DESCRIPTION("Intersil ISL1208 RTC driver");
720 MODULE_LICENSE("GPL");
721 MODULE_VERSION(DRV_VERSION);
722