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1// SPDX-License-Identifier: GPL-2.0+2/*3 * drivers/rtc/rtc-rc5t619.c4 *5 * Real time clock driver for RICOH RC5T619 power management chip.6 *7 * Copyright (C) 2019 Andreas Kemnade8 */9 10#include <linux/kernel.h>11#include <linux/device.h>12#include <linux/errno.h>13#include <linux/init.h>14#include <linux/module.h>15#include <linux/mfd/rn5t618.h>16#include <linux/platform_device.h>17#include <linux/regmap.h>18#include <linux/bcd.h>19#include <linux/rtc.h>20#include <linux/slab.h>21#include <linux/irqdomain.h>22 23struct rc5t619_rtc {24 int irq;25 struct rtc_device *rtc;26 struct rn5t618 *rn5t618;27};28 29#define CTRL1_ALARM_ENABLED 0x4030#define CTRL1_24HR 0x2031#define CTRL1_PERIODIC_MASK 0xf32 33#define CTRL2_PON 0x1034#define CTRL2_ALARM_STATUS 0x8035#define CTRL2_CTFG 0x436#define CTRL2_CTC 0x137 38#define MONTH_CENTFLAG 0x8039#define HOUR_PMFLAG 0x2040#define MDAY_DAL_EXT 0x8041 42static uint8_t rtc5t619_12hour_bcd2bin(uint8_t hour)43{44 if (hour & HOUR_PMFLAG) {45 hour = bcd2bin(hour & ~HOUR_PMFLAG);46 return hour == 12 ? 12 : 12 + hour;47 }48 49 hour = bcd2bin(hour);50 return hour == 12 ? 0 : hour;51}52 53static uint8_t rtc5t619_12hour_bin2bcd(uint8_t hour)54{55 if (!hour)56 return 0x12;57 58 if (hour < 12)59 return bin2bcd(hour);60 61 if (hour == 12)62 return 0x12 | HOUR_PMFLAG;63 64 return bin2bcd(hour - 12) | HOUR_PMFLAG;65}66 67static int rc5t619_rtc_periodic_disable(struct device *dev)68{69 struct rc5t619_rtc *rtc = dev_get_drvdata(dev);70 int err;71 72 /* disable function */73 err = regmap_update_bits(rtc->rn5t618->regmap,74 RN5T618_RTC_CTRL1, CTRL1_PERIODIC_MASK, 0);75 if (err < 0)76 return err;77 78 /* clear alarm flag and CTFG */79 err = regmap_update_bits(rtc->rn5t618->regmap, RN5T618_RTC_CTRL2,80 CTRL2_ALARM_STATUS | CTRL2_CTFG | CTRL2_CTC,81 0);82 if (err < 0)83 return err;84 85 return 0;86}87 88/* things to be done once after power on */89static int rc5t619_rtc_pon_setup(struct device *dev)90{91 struct rc5t619_rtc *rtc = dev_get_drvdata(dev);92 int err;93 unsigned int reg_data;94 95 err = regmap_read(rtc->rn5t618->regmap, RN5T618_RTC_CTRL2, ®_data);96 if (err < 0)97 return err;98 99 /* clear VDET PON */100 reg_data &= ~(CTRL2_PON | CTRL2_CTC | 0x4a); /* 0101-1011 */101 reg_data |= 0x20; /* 0010-0000 */102 err = regmap_write(rtc->rn5t618->regmap, RN5T618_RTC_CTRL2, reg_data);103 if (err < 0)104 return err;105 106 /* clearing RTC Adjust register */107 err = regmap_write(rtc->rn5t618->regmap, RN5T618_RTC_ADJUST, 0);108 if (err)109 return err;110 111 return regmap_update_bits(rtc->rn5t618->regmap,112 RN5T618_RTC_CTRL1,113 CTRL1_24HR, CTRL1_24HR);114}115 116static int rc5t619_rtc_read_time(struct device *dev, struct rtc_time *tm)117{118 struct rc5t619_rtc *rtc = dev_get_drvdata(dev);119 u8 buff[7];120 int err;121 int cent_flag;122 unsigned int ctrl1;123 unsigned int ctrl2;124 125 err = regmap_read(rtc->rn5t618->regmap, RN5T618_RTC_CTRL2, &ctrl2);126 if (err < 0)127 return err;128 129 if (ctrl2 & CTRL2_PON)130 return -EINVAL;131 132 err = regmap_read(rtc->rn5t618->regmap, RN5T618_RTC_CTRL1, &ctrl1);133 if (err < 0)134 return err;135 136 err = regmap_bulk_read(rtc->rn5t618->regmap, RN5T618_RTC_SECONDS,137 buff, sizeof(buff));138 if (err < 0)139 return err;140 141 if (buff[5] & MONTH_CENTFLAG)142 cent_flag = 1;143 else144 cent_flag = 0;145 146 tm->tm_sec = bcd2bin(buff[0]);147 tm->tm_min = bcd2bin(buff[1]);148 149 if (ctrl1 & CTRL1_24HR)150 tm->tm_hour = bcd2bin(buff[2]);151 else152 tm->tm_hour = rtc5t619_12hour_bcd2bin(buff[2]);153 154 tm->tm_wday = bcd2bin(buff[3]);155 tm->tm_mday = bcd2bin(buff[4]);156 tm->tm_mon = bcd2bin(buff[5] & 0x1f) - 1; /* back to system 0-11 */157 tm->tm_year = bcd2bin(buff[6]) + 100 * cent_flag;158 159 return 0;160}161 162static int rc5t619_rtc_set_time(struct device *dev, struct rtc_time *tm)163{164 struct rc5t619_rtc *rtc = dev_get_drvdata(dev);165 u8 buff[7];166 int err;167 int cent_flag;168 unsigned int ctrl1;169 unsigned int ctrl2;170 171 err = regmap_read(rtc->rn5t618->regmap, RN5T618_RTC_CTRL2, &ctrl2);172 if (err < 0)173 return err;174 175 if (ctrl2 & CTRL2_PON)176 rc5t619_rtc_pon_setup(dev);177 178 err = regmap_read(rtc->rn5t618->regmap, RN5T618_RTC_CTRL1, &ctrl1);179 if (err < 0)180 return err;181 182 if (tm->tm_year >= 100)183 cent_flag = 1;184 else185 cent_flag = 0;186 187 buff[0] = bin2bcd(tm->tm_sec);188 buff[1] = bin2bcd(tm->tm_min);189 190 if (ctrl1 & CTRL1_24HR)191 buff[2] = bin2bcd(tm->tm_hour);192 else193 buff[2] = rtc5t619_12hour_bin2bcd(tm->tm_hour);194 195 buff[3] = bin2bcd(tm->tm_wday);196 buff[4] = bin2bcd(tm->tm_mday);197 buff[5] = bin2bcd(tm->tm_mon + 1); /* system set 0-11 */198 buff[6] = bin2bcd(tm->tm_year - cent_flag * 100);199 200 if (cent_flag)201 buff[5] |= MONTH_CENTFLAG;202 203 err = regmap_bulk_write(rtc->rn5t618->regmap, RN5T618_RTC_SECONDS,204 buff, sizeof(buff));205 if (err < 0) {206 dev_err(dev, "failed to program new time: %d\n", err);207 return err;208 }209 210 return 0;211}212 213/* 0-disable, 1-enable */214static int rc5t619_rtc_alarm_enable(struct device *dev, unsigned int enabled)215{216 struct rc5t619_rtc *rtc = dev_get_drvdata(dev);217 218 return regmap_update_bits(rtc->rn5t618->regmap,219 RN5T618_RTC_CTRL1,220 CTRL1_ALARM_ENABLED,221 enabled ? CTRL1_ALARM_ENABLED : 0);222}223 224static int rc5t619_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)225{226 struct rc5t619_rtc *rtc = dev_get_drvdata(dev);227 u8 buff[6];228 unsigned int buff_cent;229 int err;230 int cent_flag;231 unsigned int ctrl1;232 233 err = regmap_read(rtc->rn5t618->regmap, RN5T618_RTC_CTRL1, &ctrl1);234 if (err)235 return err;236 237 err = regmap_read(rtc->rn5t618->regmap, RN5T618_RTC_MONTH, &buff_cent);238 if (err < 0) {239 dev_err(dev, "failed to read time: %d\n", err);240 return err;241 }242 243 if (buff_cent & MONTH_CENTFLAG)244 cent_flag = 1;245 else246 cent_flag = 0;247 248 err = regmap_bulk_read(rtc->rn5t618->regmap, RN5T618_RTC_ALARM_Y_SEC,249 buff, sizeof(buff));250 if (err)251 return err;252 253 buff[3] = buff[3] & 0x3f;254 255 alrm->time.tm_sec = bcd2bin(buff[0]);256 alrm->time.tm_min = bcd2bin(buff[1]);257 258 if (ctrl1 & CTRL1_24HR)259 alrm->time.tm_hour = bcd2bin(buff[2]);260 else261 alrm->time.tm_hour = rtc5t619_12hour_bcd2bin(buff[2]);262 263 alrm->time.tm_mday = bcd2bin(buff[3]);264 alrm->time.tm_mon = bcd2bin(buff[4]) - 1;265 alrm->time.tm_year = bcd2bin(buff[5]) + 100 * cent_flag;266 alrm->enabled = !!(ctrl1 & CTRL1_ALARM_ENABLED);267 dev_dbg(dev, "read alarm: %ptR\n", &alrm->time);268 269 return 0;270}271 272static int rc5t619_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)273{274 struct rc5t619_rtc *rtc = dev_get_drvdata(dev);275 u8 buff[6];276 int err;277 int cent_flag;278 unsigned int ctrl1;279 280 err = regmap_read(rtc->rn5t618->regmap, RN5T618_RTC_CTRL1, &ctrl1);281 if (err)282 return err;283 284 err = rc5t619_rtc_alarm_enable(dev, 0);285 if (err < 0)286 return err;287 288 if (rtc->irq == -1)289 return -EINVAL;290 291 if (alrm->enabled == 0)292 return 0;293 294 if (alrm->time.tm_year >= 100)295 cent_flag = 1;296 else297 cent_flag = 0;298 299 alrm->time.tm_mon += 1;300 buff[0] = bin2bcd(alrm->time.tm_sec);301 buff[1] = bin2bcd(alrm->time.tm_min);302 303 if (ctrl1 & CTRL1_24HR)304 buff[2] = bin2bcd(alrm->time.tm_hour);305 else306 buff[2] = rtc5t619_12hour_bin2bcd(alrm->time.tm_hour);307 308 buff[3] = bin2bcd(alrm->time.tm_mday);309 buff[4] = bin2bcd(alrm->time.tm_mon);310 buff[5] = bin2bcd(alrm->time.tm_year - 100 * cent_flag);311 buff[3] |= MDAY_DAL_EXT;312 313 err = regmap_bulk_write(rtc->rn5t618->regmap, RN5T618_RTC_ALARM_Y_SEC,314 buff, sizeof(buff));315 if (err < 0)316 return err;317 318 return rc5t619_rtc_alarm_enable(dev, alrm->enabled);319}320 321static const struct rtc_class_ops rc5t619_rtc_ops = {322 .read_time = rc5t619_rtc_read_time,323 .set_time = rc5t619_rtc_set_time,324 .set_alarm = rc5t619_rtc_set_alarm,325 .read_alarm = rc5t619_rtc_read_alarm,326 .alarm_irq_enable = rc5t619_rtc_alarm_enable,327};328 329static int rc5t619_rtc_alarm_flag_clr(struct device *dev)330{331 struct rc5t619_rtc *rtc = dev_get_drvdata(dev);332 333 /* clear alarm-D status bits.*/334 return regmap_update_bits(rtc->rn5t618->regmap,335 RN5T618_RTC_CTRL2,336 CTRL2_ALARM_STATUS | CTRL2_CTC, 0);337}338 339static irqreturn_t rc5t619_rtc_irq(int irq, void *data)340{341 struct device *dev = data;342 struct rc5t619_rtc *rtc = dev_get_drvdata(dev);343 344 rc5t619_rtc_alarm_flag_clr(dev);345 346 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);347 return IRQ_HANDLED;348}349 350static int rc5t619_rtc_probe(struct platform_device *pdev)351{352 struct device *dev = &pdev->dev;353 struct rn5t618 *rn5t618 = dev_get_drvdata(pdev->dev.parent);354 struct rc5t619_rtc *rtc;355 unsigned int ctrl2;356 int err;357 358 rtc = devm_kzalloc(dev, sizeof(*rtc), GFP_KERNEL);359 if (!rtc)360 return -ENOMEM;361 362 rtc->rn5t618 = rn5t618;363 364 dev_set_drvdata(dev, rtc);365 rtc->irq = -1;366 367 if (rn5t618->irq_data)368 rtc->irq = regmap_irq_get_virq(rn5t618->irq_data,369 RN5T618_IRQ_RTC);370 371 if (rtc->irq < 0)372 rtc->irq = -1;373 374 err = regmap_read(rtc->rn5t618->regmap, RN5T618_RTC_CTRL2, &ctrl2);375 if (err < 0)376 return err;377 378 /* disable rtc periodic function */379 err = rc5t619_rtc_periodic_disable(&pdev->dev);380 if (err)381 return err;382 383 if (ctrl2 & CTRL2_PON) {384 err = rc5t619_rtc_alarm_flag_clr(&pdev->dev);385 if (err)386 return err;387 }388 389 rtc->rtc = devm_rtc_allocate_device(&pdev->dev);390 if (IS_ERR(rtc->rtc)) {391 err = PTR_ERR(rtc->rtc);392 dev_err(dev, "RTC device register: err %d\n", err);393 return err;394 }395 396 rtc->rtc->ops = &rc5t619_rtc_ops;397 rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_1900;398 rtc->rtc->range_max = RTC_TIMESTAMP_END_2099;399 400 /* set interrupt and enable it */401 if (rtc->irq != -1) {402 err = devm_request_threaded_irq(&pdev->dev, rtc->irq, NULL,403 rc5t619_rtc_irq,404 IRQF_ONESHOT,405 "rtc-rc5t619",406 &pdev->dev);407 if (err < 0) {408 dev_err(&pdev->dev, "request IRQ:%d fail\n", rtc->irq);409 rtc->irq = -1;410 411 err = rc5t619_rtc_alarm_enable(&pdev->dev, 0);412 if (err)413 return err;414 415 } else {416 /* enable wake */417 device_init_wakeup(&pdev->dev, 1);418 enable_irq_wake(rtc->irq);419 }420 } else {421 /* system don't want to using alarm interrupt, so close it */422 err = rc5t619_rtc_alarm_enable(&pdev->dev, 0);423 if (err)424 return err;425 426 dev_warn(&pdev->dev, "rc5t619 interrupt is disabled\n");427 }428 429 return devm_rtc_register_device(rtc->rtc);430}431 432static const struct platform_device_id rc5t619_rtc_id[] = {433 {434 .name = "rc5t619-rtc",435 }, {436 /* sentinel */437 }438};439MODULE_DEVICE_TABLE(platform, rc5t619_rtc_id);440 441static struct platform_driver rc5t619_rtc_driver = {442 .driver = {443 .name = "rc5t619-rtc",444 },445 .probe = rc5t619_rtc_probe,446 .id_table = rc5t619_rtc_id,447};448module_platform_driver(rc5t619_rtc_driver);449 450MODULE_DESCRIPTION("RICOH RC5T619 RTC driver");451MODULE_LICENSE("GPL");452