x86/mm/pat: Don't report PAT on CPUs that don't support it
[linux/fpc-iii.git] / drivers / rtc / rtc-abx80x.c
blobfea9a60b06cf6dd25b1a078bf6e812265aa0acc1
1 /*
2 * A driver for the I2C members of the Abracon AB x8xx RTC family,
3 * and compatible: AB 1805 and AB 0805
5 * Copyright 2014-2015 Macq S.A.
7 * Author: Philippe De Muyter <phdm@macqel.be>
8 * Author: Alexandre Belloni <alexandre.belloni@free-electrons.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
16 #include <linux/bcd.h>
17 #include <linux/i2c.h>
18 #include <linux/module.h>
19 #include <linux/rtc.h>
21 #define ABX8XX_REG_HTH 0x00
22 #define ABX8XX_REG_SC 0x01
23 #define ABX8XX_REG_MN 0x02
24 #define ABX8XX_REG_HR 0x03
25 #define ABX8XX_REG_DA 0x04
26 #define ABX8XX_REG_MO 0x05
27 #define ABX8XX_REG_YR 0x06
28 #define ABX8XX_REG_WD 0x07
30 #define ABX8XX_REG_AHTH 0x08
31 #define ABX8XX_REG_ASC 0x09
32 #define ABX8XX_REG_AMN 0x0a
33 #define ABX8XX_REG_AHR 0x0b
34 #define ABX8XX_REG_ADA 0x0c
35 #define ABX8XX_REG_AMO 0x0d
36 #define ABX8XX_REG_AWD 0x0e
38 #define ABX8XX_REG_STATUS 0x0f
39 #define ABX8XX_STATUS_AF BIT(2)
41 #define ABX8XX_REG_CTRL1 0x10
42 #define ABX8XX_CTRL_WRITE BIT(0)
43 #define ABX8XX_CTRL_ARST BIT(2)
44 #define ABX8XX_CTRL_12_24 BIT(6)
46 #define ABX8XX_REG_IRQ 0x12
47 #define ABX8XX_IRQ_AIE BIT(2)
48 #define ABX8XX_IRQ_IM_1_4 (0x3 << 5)
50 #define ABX8XX_REG_CD_TIMER_CTL 0x18
52 #define ABX8XX_REG_OSC 0x1c
53 #define ABX8XX_OSC_FOS BIT(3)
54 #define ABX8XX_OSC_BOS BIT(4)
55 #define ABX8XX_OSC_ACAL_512 BIT(5)
56 #define ABX8XX_OSC_ACAL_1024 BIT(6)
58 #define ABX8XX_OSC_OSEL BIT(7)
60 #define ABX8XX_REG_OSS 0x1d
61 #define ABX8XX_OSS_OF BIT(1)
62 #define ABX8XX_OSS_OMODE BIT(4)
64 #define ABX8XX_REG_CFG_KEY 0x1f
65 #define ABX8XX_CFG_KEY_OSC 0xa1
66 #define ABX8XX_CFG_KEY_MISC 0x9d
68 #define ABX8XX_REG_ID0 0x28
70 #define ABX8XX_REG_TRICKLE 0x20
71 #define ABX8XX_TRICKLE_CHARGE_ENABLE 0xa0
72 #define ABX8XX_TRICKLE_STANDARD_DIODE 0x8
73 #define ABX8XX_TRICKLE_SCHOTTKY_DIODE 0x4
75 static u8 trickle_resistors[] = {0, 3, 6, 11};
77 enum abx80x_chip {AB0801, AB0803, AB0804, AB0805,
78 AB1801, AB1803, AB1804, AB1805, ABX80X};
80 struct abx80x_cap {
81 u16 pn;
82 bool has_tc;
85 static struct abx80x_cap abx80x_caps[] = {
86 [AB0801] = {.pn = 0x0801},
87 [AB0803] = {.pn = 0x0803},
88 [AB0804] = {.pn = 0x0804, .has_tc = true},
89 [AB0805] = {.pn = 0x0805, .has_tc = true},
90 [AB1801] = {.pn = 0x1801},
91 [AB1803] = {.pn = 0x1803},
92 [AB1804] = {.pn = 0x1804, .has_tc = true},
93 [AB1805] = {.pn = 0x1805, .has_tc = true},
94 [ABX80X] = {.pn = 0}
97 static int abx80x_is_rc_mode(struct i2c_client *client)
99 int flags = 0;
101 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);
102 if (flags < 0) {
103 dev_err(&client->dev,
104 "Failed to read autocalibration attribute\n");
105 return flags;
108 return (flags & ABX8XX_OSS_OMODE) ? 1 : 0;
111 static int abx80x_enable_trickle_charger(struct i2c_client *client,
112 u8 trickle_cfg)
114 int err;
117 * Write the configuration key register to enable access to the Trickle
118 * register
120 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY,
121 ABX8XX_CFG_KEY_MISC);
122 if (err < 0) {
123 dev_err(&client->dev, "Unable to write configuration key\n");
124 return -EIO;
127 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_TRICKLE,
128 ABX8XX_TRICKLE_CHARGE_ENABLE |
129 trickle_cfg);
130 if (err < 0) {
131 dev_err(&client->dev, "Unable to write trickle register\n");
132 return -EIO;
135 return 0;
138 static int abx80x_rtc_read_time(struct device *dev, struct rtc_time *tm)
140 struct i2c_client *client = to_i2c_client(dev);
141 unsigned char buf[8];
142 int err, flags, rc_mode = 0;
144 /* Read the Oscillator Failure only in XT mode */
145 rc_mode = abx80x_is_rc_mode(client);
146 if (rc_mode < 0)
147 return rc_mode;
149 if (!rc_mode) {
150 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);
151 if (flags < 0)
152 return flags;
154 if (flags & ABX8XX_OSS_OF) {
155 dev_err(dev, "Oscillator failure, data is invalid.\n");
156 return -EINVAL;
160 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH,
161 sizeof(buf), buf);
162 if (err < 0) {
163 dev_err(&client->dev, "Unable to read date\n");
164 return -EIO;
167 tm->tm_sec = bcd2bin(buf[ABX8XX_REG_SC] & 0x7F);
168 tm->tm_min = bcd2bin(buf[ABX8XX_REG_MN] & 0x7F);
169 tm->tm_hour = bcd2bin(buf[ABX8XX_REG_HR] & 0x3F);
170 tm->tm_wday = buf[ABX8XX_REG_WD] & 0x7;
171 tm->tm_mday = bcd2bin(buf[ABX8XX_REG_DA] & 0x3F);
172 tm->tm_mon = bcd2bin(buf[ABX8XX_REG_MO] & 0x1F) - 1;
173 tm->tm_year = bcd2bin(buf[ABX8XX_REG_YR]) + 100;
175 err = rtc_valid_tm(tm);
176 if (err < 0)
177 dev_err(&client->dev, "retrieved date/time is not valid.\n");
179 return err;
182 static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm)
184 struct i2c_client *client = to_i2c_client(dev);
185 unsigned char buf[8];
186 int err, flags;
188 if (tm->tm_year < 100)
189 return -EINVAL;
191 buf[ABX8XX_REG_HTH] = 0;
192 buf[ABX8XX_REG_SC] = bin2bcd(tm->tm_sec);
193 buf[ABX8XX_REG_MN] = bin2bcd(tm->tm_min);
194 buf[ABX8XX_REG_HR] = bin2bcd(tm->tm_hour);
195 buf[ABX8XX_REG_DA] = bin2bcd(tm->tm_mday);
196 buf[ABX8XX_REG_MO] = bin2bcd(tm->tm_mon + 1);
197 buf[ABX8XX_REG_YR] = bin2bcd(tm->tm_year - 100);
198 buf[ABX8XX_REG_WD] = tm->tm_wday;
200 err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_HTH,
201 sizeof(buf), buf);
202 if (err < 0) {
203 dev_err(&client->dev, "Unable to write to date registers\n");
204 return -EIO;
207 /* Clear the OF bit of Oscillator Status Register */
208 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS);
209 if (flags < 0)
210 return flags;
212 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSS,
213 flags & ~ABX8XX_OSS_OF);
214 if (err < 0) {
215 dev_err(&client->dev, "Unable to write oscillator status register\n");
216 return err;
219 return 0;
222 static irqreturn_t abx80x_handle_irq(int irq, void *dev_id)
224 struct i2c_client *client = dev_id;
225 struct rtc_device *rtc = i2c_get_clientdata(client);
226 int status;
228 status = i2c_smbus_read_byte_data(client, ABX8XX_REG_STATUS);
229 if (status < 0)
230 return IRQ_NONE;
232 if (status & ABX8XX_STATUS_AF)
233 rtc_update_irq(rtc, 1, RTC_AF | RTC_IRQF);
235 i2c_smbus_write_byte_data(client, ABX8XX_REG_STATUS, 0);
237 return IRQ_HANDLED;
240 static int abx80x_read_alarm(struct device *dev, struct rtc_wkalrm *t)
242 struct i2c_client *client = to_i2c_client(dev);
243 unsigned char buf[7];
245 int irq_mask, err;
247 if (client->irq <= 0)
248 return -EINVAL;
250 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ASC,
251 sizeof(buf), buf);
252 if (err)
253 return err;
255 irq_mask = i2c_smbus_read_byte_data(client, ABX8XX_REG_IRQ);
256 if (irq_mask < 0)
257 return irq_mask;
259 t->time.tm_sec = bcd2bin(buf[0] & 0x7F);
260 t->time.tm_min = bcd2bin(buf[1] & 0x7F);
261 t->time.tm_hour = bcd2bin(buf[2] & 0x3F);
262 t->time.tm_mday = bcd2bin(buf[3] & 0x3F);
263 t->time.tm_mon = bcd2bin(buf[4] & 0x1F) - 1;
264 t->time.tm_wday = buf[5] & 0x7;
266 t->enabled = !!(irq_mask & ABX8XX_IRQ_AIE);
267 t->pending = (buf[6] & ABX8XX_STATUS_AF) && t->enabled;
269 return err;
272 static int abx80x_set_alarm(struct device *dev, struct rtc_wkalrm *t)
274 struct i2c_client *client = to_i2c_client(dev);
275 u8 alarm[6];
276 int err;
278 if (client->irq <= 0)
279 return -EINVAL;
281 alarm[0] = 0x0;
282 alarm[1] = bin2bcd(t->time.tm_sec);
283 alarm[2] = bin2bcd(t->time.tm_min);
284 alarm[3] = bin2bcd(t->time.tm_hour);
285 alarm[4] = bin2bcd(t->time.tm_mday);
286 alarm[5] = bin2bcd(t->time.tm_mon + 1);
288 err = i2c_smbus_write_i2c_block_data(client, ABX8XX_REG_AHTH,
289 sizeof(alarm), alarm);
290 if (err < 0) {
291 dev_err(&client->dev, "Unable to write alarm registers\n");
292 return -EIO;
295 if (t->enabled) {
296 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
297 (ABX8XX_IRQ_IM_1_4 |
298 ABX8XX_IRQ_AIE));
299 if (err)
300 return err;
303 return 0;
306 static int abx80x_rtc_set_autocalibration(struct device *dev,
307 int autocalibration)
309 struct i2c_client *client = to_i2c_client(dev);
310 int retval, flags = 0;
312 if ((autocalibration != 0) && (autocalibration != 1024) &&
313 (autocalibration != 512)) {
314 dev_err(dev, "autocalibration value outside permitted range\n");
315 return -EINVAL;
318 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);
319 if (flags < 0)
320 return flags;
322 if (autocalibration == 0) {
323 flags &= ~(ABX8XX_OSC_ACAL_512 | ABX8XX_OSC_ACAL_1024);
324 } else if (autocalibration == 1024) {
325 /* 1024 autocalibration is 0x10 */
326 flags |= ABX8XX_OSC_ACAL_1024;
327 flags &= ~(ABX8XX_OSC_ACAL_512);
328 } else {
329 /* 512 autocalibration is 0x11 */
330 flags |= (ABX8XX_OSC_ACAL_1024 | ABX8XX_OSC_ACAL_512);
333 /* Unlock write access to Oscillator Control Register */
334 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY,
335 ABX8XX_CFG_KEY_OSC);
336 if (retval < 0) {
337 dev_err(dev, "Failed to write CONFIG_KEY register\n");
338 return retval;
341 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags);
343 return retval;
346 static int abx80x_rtc_get_autocalibration(struct device *dev)
348 struct i2c_client *client = to_i2c_client(dev);
349 int flags = 0, autocalibration;
351 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);
352 if (flags < 0)
353 return flags;
355 if (flags & ABX8XX_OSC_ACAL_512)
356 autocalibration = 512;
357 else if (flags & ABX8XX_OSC_ACAL_1024)
358 autocalibration = 1024;
359 else
360 autocalibration = 0;
362 return autocalibration;
365 static ssize_t autocalibration_store(struct device *dev,
366 struct device_attribute *attr,
367 const char *buf, size_t count)
369 int retval;
370 unsigned long autocalibration = 0;
372 retval = kstrtoul(buf, 10, &autocalibration);
373 if (retval < 0) {
374 dev_err(dev, "Failed to store RTC autocalibration attribute\n");
375 return -EINVAL;
378 retval = abx80x_rtc_set_autocalibration(dev, autocalibration);
380 return retval ? retval : count;
383 static ssize_t autocalibration_show(struct device *dev,
384 struct device_attribute *attr, char *buf)
386 int autocalibration = 0;
388 autocalibration = abx80x_rtc_get_autocalibration(dev);
389 if (autocalibration < 0) {
390 dev_err(dev, "Failed to read RTC autocalibration\n");
391 sprintf(buf, "0\n");
392 return autocalibration;
395 return sprintf(buf, "%d\n", autocalibration);
398 static DEVICE_ATTR_RW(autocalibration);
400 static ssize_t oscillator_store(struct device *dev,
401 struct device_attribute *attr,
402 const char *buf, size_t count)
404 struct i2c_client *client = to_i2c_client(dev);
405 int retval, flags, rc_mode = 0;
407 if (strncmp(buf, "rc", 2) == 0) {
408 rc_mode = 1;
409 } else if (strncmp(buf, "xtal", 4) == 0) {
410 rc_mode = 0;
411 } else {
412 dev_err(dev, "Oscillator selection value outside permitted ones\n");
413 return -EINVAL;
416 flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSC);
417 if (flags < 0)
418 return flags;
420 if (rc_mode == 0)
421 flags &= ~(ABX8XX_OSC_OSEL);
422 else
423 flags |= (ABX8XX_OSC_OSEL);
425 /* Unlock write access on Oscillator Control register */
426 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_CFG_KEY,
427 ABX8XX_CFG_KEY_OSC);
428 if (retval < 0) {
429 dev_err(dev, "Failed to write CONFIG_KEY register\n");
430 return retval;
433 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSC, flags);
434 if (retval < 0) {
435 dev_err(dev, "Failed to write Oscillator Control register\n");
436 return retval;
439 return retval ? retval : count;
442 static ssize_t oscillator_show(struct device *dev,
443 struct device_attribute *attr, char *buf)
445 int rc_mode = 0;
446 struct i2c_client *client = to_i2c_client(dev);
448 rc_mode = abx80x_is_rc_mode(client);
450 if (rc_mode < 0) {
451 dev_err(dev, "Failed to read RTC oscillator selection\n");
452 sprintf(buf, "\n");
453 return rc_mode;
456 if (rc_mode)
457 return sprintf(buf, "rc\n");
458 else
459 return sprintf(buf, "xtal\n");
462 static DEVICE_ATTR_RW(oscillator);
464 static struct attribute *rtc_calib_attrs[] = {
465 &dev_attr_autocalibration.attr,
466 &dev_attr_oscillator.attr,
467 NULL,
470 static const struct attribute_group rtc_calib_attr_group = {
471 .attrs = rtc_calib_attrs,
474 static int abx80x_alarm_irq_enable(struct device *dev, unsigned int enabled)
476 struct i2c_client *client = to_i2c_client(dev);
477 int err;
479 if (enabled)
480 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
481 (ABX8XX_IRQ_IM_1_4 |
482 ABX8XX_IRQ_AIE));
483 else
484 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_IRQ,
485 ABX8XX_IRQ_IM_1_4);
486 return err;
489 static const struct rtc_class_ops abx80x_rtc_ops = {
490 .read_time = abx80x_rtc_read_time,
491 .set_time = abx80x_rtc_set_time,
492 .read_alarm = abx80x_read_alarm,
493 .set_alarm = abx80x_set_alarm,
494 .alarm_irq_enable = abx80x_alarm_irq_enable,
497 static int abx80x_dt_trickle_cfg(struct device_node *np)
499 const char *diode;
500 int trickle_cfg = 0;
501 int i, ret;
502 u32 tmp;
504 ret = of_property_read_string(np, "abracon,tc-diode", &diode);
505 if (ret)
506 return ret;
508 if (!strcmp(diode, "standard"))
509 trickle_cfg |= ABX8XX_TRICKLE_STANDARD_DIODE;
510 else if (!strcmp(diode, "schottky"))
511 trickle_cfg |= ABX8XX_TRICKLE_SCHOTTKY_DIODE;
512 else
513 return -EINVAL;
515 ret = of_property_read_u32(np, "abracon,tc-resistor", &tmp);
516 if (ret)
517 return ret;
519 for (i = 0; i < sizeof(trickle_resistors); i++)
520 if (trickle_resistors[i] == tmp)
521 break;
523 if (i == sizeof(trickle_resistors))
524 return -EINVAL;
526 return (trickle_cfg | i);
529 static void rtc_calib_remove_sysfs_group(void *_dev)
531 struct device *dev = _dev;
533 sysfs_remove_group(&dev->kobj, &rtc_calib_attr_group);
536 static int abx80x_probe(struct i2c_client *client,
537 const struct i2c_device_id *id)
539 struct device_node *np = client->dev.of_node;
540 struct rtc_device *rtc;
541 int i, data, err, trickle_cfg = -EINVAL;
542 char buf[7];
543 unsigned int part = id->driver_data;
544 unsigned int partnumber;
545 unsigned int majrev, minrev;
546 unsigned int lot;
547 unsigned int wafer;
548 unsigned int uid;
550 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
551 return -ENODEV;
553 err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_ID0,
554 sizeof(buf), buf);
555 if (err < 0) {
556 dev_err(&client->dev, "Unable to read partnumber\n");
557 return -EIO;
560 partnumber = (buf[0] << 8) | buf[1];
561 majrev = buf[2] >> 3;
562 minrev = buf[2] & 0x7;
563 lot = ((buf[4] & 0x80) << 2) | ((buf[6] & 0x80) << 1) | buf[3];
564 uid = ((buf[4] & 0x7f) << 8) | buf[5];
565 wafer = (buf[6] & 0x7c) >> 2;
566 dev_info(&client->dev, "model %04x, revision %u.%u, lot %x, wafer %x, uid %x\n",
567 partnumber, majrev, minrev, lot, wafer, uid);
569 data = i2c_smbus_read_byte_data(client, ABX8XX_REG_CTRL1);
570 if (data < 0) {
571 dev_err(&client->dev, "Unable to read control register\n");
572 return -EIO;
575 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CTRL1,
576 ((data & ~(ABX8XX_CTRL_12_24 |
577 ABX8XX_CTRL_ARST)) |
578 ABX8XX_CTRL_WRITE));
579 if (err < 0) {
580 dev_err(&client->dev, "Unable to write control register\n");
581 return -EIO;
584 /* part autodetection */
585 if (part == ABX80X) {
586 for (i = 0; abx80x_caps[i].pn; i++)
587 if (partnumber == abx80x_caps[i].pn)
588 break;
589 if (abx80x_caps[i].pn == 0) {
590 dev_err(&client->dev, "Unknown part: %04x\n",
591 partnumber);
592 return -EINVAL;
594 part = i;
597 if (partnumber != abx80x_caps[part].pn) {
598 dev_err(&client->dev, "partnumber mismatch %04x != %04x\n",
599 partnumber, abx80x_caps[part].pn);
600 return -EINVAL;
603 if (np && abx80x_caps[part].has_tc)
604 trickle_cfg = abx80x_dt_trickle_cfg(np);
606 if (trickle_cfg > 0) {
607 dev_info(&client->dev, "Enabling trickle charger: %02x\n",
608 trickle_cfg);
609 abx80x_enable_trickle_charger(client, trickle_cfg);
612 err = i2c_smbus_write_byte_data(client, ABX8XX_REG_CD_TIMER_CTL,
613 BIT(2));
614 if (err)
615 return err;
617 rtc = devm_rtc_device_register(&client->dev, "abx8xx",
618 &abx80x_rtc_ops, THIS_MODULE);
620 if (IS_ERR(rtc))
621 return PTR_ERR(rtc);
623 i2c_set_clientdata(client, rtc);
625 if (client->irq > 0) {
626 dev_info(&client->dev, "IRQ %d supplied\n", client->irq);
627 err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
628 abx80x_handle_irq,
629 IRQF_SHARED | IRQF_ONESHOT,
630 "abx8xx",
631 client);
632 if (err) {
633 dev_err(&client->dev, "unable to request IRQ, alarms disabled\n");
634 client->irq = 0;
638 /* Export sysfs entries */
639 err = sysfs_create_group(&(&client->dev)->kobj, &rtc_calib_attr_group);
640 if (err) {
641 dev_err(&client->dev, "Failed to create sysfs group: %d\n",
642 err);
643 return err;
646 err = devm_add_action_or_reset(&client->dev,
647 rtc_calib_remove_sysfs_group,
648 &client->dev);
649 if (err)
650 dev_err(&client->dev,
651 "Failed to add sysfs cleanup action: %d\n",
652 err);
654 return err;
657 static int abx80x_remove(struct i2c_client *client)
659 return 0;
662 static const struct i2c_device_id abx80x_id[] = {
663 { "abx80x", ABX80X },
664 { "ab0801", AB0801 },
665 { "ab0803", AB0803 },
666 { "ab0804", AB0804 },
667 { "ab0805", AB0805 },
668 { "ab1801", AB1801 },
669 { "ab1803", AB1803 },
670 { "ab1804", AB1804 },
671 { "ab1805", AB1805 },
672 { "rv1805", AB1805 },
675 MODULE_DEVICE_TABLE(i2c, abx80x_id);
677 static struct i2c_driver abx80x_driver = {
678 .driver = {
679 .name = "rtc-abx80x",
681 .probe = abx80x_probe,
682 .remove = abx80x_remove,
683 .id_table = abx80x_id,
686 module_i2c_driver(abx80x_driver);
688 MODULE_AUTHOR("Philippe De Muyter <phdm@macqel.be>");
689 MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@free-electrons.com>");
690 MODULE_DESCRIPTION("Abracon ABX80X RTC driver");
691 MODULE_LICENSE("GPL v2");