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1// SPDX-License-Identifier: GPL-2.0-or-later2//3// Copyright (C) 2018 ROHM Semiconductors4//5// RTC driver for ROHM BD71828 and BD71815 PMIC6 7#include <linux/bcd.h>8#include <linux/mfd/rohm-bd71815.h>9#include <linux/mfd/rohm-bd71828.h>10#include <linux/module.h>11#include <linux/of.h>12#include <linux/platform_device.h>13#include <linux/regmap.h>14#include <linux/rtc.h>15 16/*17 * On BD71828 and BD71815 the ALM0 MASK is 14 bytes after the ALM018 * block start19 */20#define BD718XX_ALM_EN_OFFSET 1421 22/*23 * We read regs RTC_SEC => RTC_YEAR24 * this struct is ordered according to chip registers.25 * Keep it u8 only (or packed) to avoid padding issues.26 */27struct bd70528_rtc_day {28 u8 sec;29 u8 min;30 u8 hour;31} __packed;32 33struct bd70528_rtc_data {34 struct bd70528_rtc_day time;35 u8 week;36 u8 day;37 u8 month;38 u8 year;39} __packed;40 41struct bd71828_rtc_alm {42 struct bd70528_rtc_data alm0;43 struct bd70528_rtc_data alm1;44 u8 alm_mask;45 u8 alm1_mask;46} __packed;47 48struct bd70528_rtc {49 struct rohm_regmap_dev *parent;50 struct regmap *regmap;51 struct device *dev;52 u8 reg_time_start;53 u8 bd718xx_alm_block_start;54};55 56static inline void tmday2rtc(struct rtc_time *t, struct bd70528_rtc_day *d)57{58 d->sec &= ~BD70528_MASK_RTC_SEC;59 d->min &= ~BD70528_MASK_RTC_MINUTE;60 d->hour &= ~BD70528_MASK_RTC_HOUR;61 d->sec |= bin2bcd(t->tm_sec);62 d->min |= bin2bcd(t->tm_min);63 d->hour |= bin2bcd(t->tm_hour);64}65 66static inline void tm2rtc(struct rtc_time *t, struct bd70528_rtc_data *r)67{68 r->day &= ~BD70528_MASK_RTC_DAY;69 r->week &= ~BD70528_MASK_RTC_WEEK;70 r->month &= ~BD70528_MASK_RTC_MONTH;71 /*72 * PM and 24H bits are not used by Wake - thus we clear them73 * here and not in tmday2rtc() which is also used by wake.74 */75 r->time.hour &= ~(BD70528_MASK_RTC_HOUR_PM | BD70528_MASK_RTC_HOUR_24H);76 77 tmday2rtc(t, &r->time);78 /*79 * We do always set time in 24H mode.80 */81 r->time.hour |= BD70528_MASK_RTC_HOUR_24H;82 r->day |= bin2bcd(t->tm_mday);83 r->week |= bin2bcd(t->tm_wday);84 r->month |= bin2bcd(t->tm_mon + 1);85 r->year = bin2bcd(t->tm_year - 100);86}87 88static inline void rtc2tm(struct bd70528_rtc_data *r, struct rtc_time *t)89{90 t->tm_sec = bcd2bin(r->time.sec & BD70528_MASK_RTC_SEC);91 t->tm_min = bcd2bin(r->time.min & BD70528_MASK_RTC_MINUTE);92 t->tm_hour = bcd2bin(r->time.hour & BD70528_MASK_RTC_HOUR);93 /*94 * If RTC is in 12H mode, then bit BD70528_MASK_RTC_HOUR_PM95 * is not BCD value but tells whether it is AM or PM96 */97 if (!(r->time.hour & BD70528_MASK_RTC_HOUR_24H)) {98 t->tm_hour %= 12;99 if (r->time.hour & BD70528_MASK_RTC_HOUR_PM)100 t->tm_hour += 12;101 }102 t->tm_mday = bcd2bin(r->day & BD70528_MASK_RTC_DAY);103 t->tm_mon = bcd2bin(r->month & BD70528_MASK_RTC_MONTH) - 1;104 t->tm_year = 100 + bcd2bin(r->year & BD70528_MASK_RTC_YEAR);105 t->tm_wday = bcd2bin(r->week & BD70528_MASK_RTC_WEEK);106}107 108static int bd71828_set_alarm(struct device *dev, struct rtc_wkalrm *a)109{110 int ret;111 struct bd71828_rtc_alm alm;112 struct bd70528_rtc *r = dev_get_drvdata(dev);113 114 ret = regmap_bulk_read(r->regmap, r->bd718xx_alm_block_start, &alm,115 sizeof(alm));116 if (ret) {117 dev_err(dev, "Failed to read alarm regs\n");118 return ret;119 }120 121 tm2rtc(&a->time, &alm.alm0);122 123 if (!a->enabled)124 alm.alm_mask &= ~BD70528_MASK_ALM_EN;125 else126 alm.alm_mask |= BD70528_MASK_ALM_EN;127 128 ret = regmap_bulk_write(r->regmap, r->bd718xx_alm_block_start, &alm,129 sizeof(alm));130 if (ret)131 dev_err(dev, "Failed to set alarm time\n");132 133 return ret;134 135}136 137static int bd71828_read_alarm(struct device *dev, struct rtc_wkalrm *a)138{139 int ret;140 struct bd71828_rtc_alm alm;141 struct bd70528_rtc *r = dev_get_drvdata(dev);142 143 ret = regmap_bulk_read(r->regmap, r->bd718xx_alm_block_start, &alm,144 sizeof(alm));145 if (ret) {146 dev_err(dev, "Failed to read alarm regs\n");147 return ret;148 }149 150 rtc2tm(&alm.alm0, &a->time);151 a->time.tm_mday = -1;152 a->time.tm_mon = -1;153 a->time.tm_year = -1;154 a->enabled = !!(alm.alm_mask & BD70528_MASK_ALM_EN);155 a->pending = 0;156 157 return 0;158}159 160static int bd71828_set_time(struct device *dev, struct rtc_time *t)161{162 int ret;163 struct bd70528_rtc_data rtc_data;164 struct bd70528_rtc *r = dev_get_drvdata(dev);165 166 ret = regmap_bulk_read(r->regmap, r->reg_time_start, &rtc_data,167 sizeof(rtc_data));168 if (ret) {169 dev_err(dev, "Failed to read RTC time registers\n");170 return ret;171 }172 tm2rtc(t, &rtc_data);173 174 ret = regmap_bulk_write(r->regmap, r->reg_time_start, &rtc_data,175 sizeof(rtc_data));176 if (ret)177 dev_err(dev, "Failed to set RTC time\n");178 179 return ret;180}181 182static int bd70528_get_time(struct device *dev, struct rtc_time *t)183{184 struct bd70528_rtc *r = dev_get_drvdata(dev);185 struct bd70528_rtc_data rtc_data;186 int ret;187 188 /* read the RTC date and time registers all at once */189 ret = regmap_bulk_read(r->regmap, r->reg_time_start, &rtc_data,190 sizeof(rtc_data));191 if (ret) {192 dev_err(dev, "Failed to read RTC time (err %d)\n", ret);193 return ret;194 }195 196 rtc2tm(&rtc_data, t);197 198 return 0;199}200 201static int bd71828_alm_enable(struct device *dev, unsigned int enabled)202{203 int ret;204 struct bd70528_rtc *r = dev_get_drvdata(dev);205 unsigned int enableval = BD70528_MASK_ALM_EN;206 207 if (!enabled)208 enableval = 0;209 210 ret = regmap_update_bits(r->regmap, r->bd718xx_alm_block_start +211 BD718XX_ALM_EN_OFFSET, BD70528_MASK_ALM_EN,212 enableval);213 if (ret)214 dev_err(dev, "Failed to change alarm state\n");215 216 return ret;217}218 219static const struct rtc_class_ops bd71828_rtc_ops = {220 .read_time = bd70528_get_time,221 .set_time = bd71828_set_time,222 .read_alarm = bd71828_read_alarm,223 .set_alarm = bd71828_set_alarm,224 .alarm_irq_enable = bd71828_alm_enable,225};226 227static irqreturn_t alm_hndlr(int irq, void *data)228{229 struct rtc_device *rtc = data;230 231 rtc_update_irq(rtc, 1, RTC_IRQF | RTC_AF | RTC_PF);232 return IRQ_HANDLED;233}234 235static int bd70528_probe(struct platform_device *pdev)236{237 struct bd70528_rtc *bd_rtc;238 const struct rtc_class_ops *rtc_ops;239 const char *irq_name;240 int ret;241 struct rtc_device *rtc;242 int irq;243 unsigned int hr;244 u8 hour_reg;245 enum rohm_chip_type chip = platform_get_device_id(pdev)->driver_data;246 247 bd_rtc = devm_kzalloc(&pdev->dev, sizeof(*bd_rtc), GFP_KERNEL);248 if (!bd_rtc)249 return -ENOMEM;250 251 bd_rtc->regmap = dev_get_regmap(pdev->dev.parent, NULL);252 if (!bd_rtc->regmap) {253 dev_err(&pdev->dev, "No regmap\n");254 return -EINVAL;255 }256 257 bd_rtc->dev = &pdev->dev;258 rtc_ops = &bd71828_rtc_ops;259 260 switch (chip) {261 case ROHM_CHIP_TYPE_BD71815:262 irq_name = "bd71815-rtc-alm-0";263 bd_rtc->reg_time_start = BD71815_REG_RTC_START;264 265 /*266 * See also BD718XX_ALM_EN_OFFSET:267 * This works for BD71828 and BD71815 as they have same offset268 * between ALM0 start and ALM0_MASK. If new ICs are to be269 * added this requires proper check as ALM0_MASK is not located270 * at the end of ALM0 block - but after all ALM blocks so if271 * amount of ALMs differ the offset to enable/disable is likely272 * to be incorrect and enable/disable must be given as own273 * reg address here.274 */275 bd_rtc->bd718xx_alm_block_start = BD71815_REG_RTC_ALM_START;276 hour_reg = BD71815_REG_HOUR;277 break;278 case ROHM_CHIP_TYPE_BD71828:279 irq_name = "bd71828-rtc-alm-0";280 bd_rtc->reg_time_start = BD71828_REG_RTC_START;281 bd_rtc->bd718xx_alm_block_start = BD71828_REG_RTC_ALM_START;282 hour_reg = BD71828_REG_RTC_HOUR;283 break;284 default:285 dev_err(&pdev->dev, "Unknown chip\n");286 return -ENOENT;287 }288 289 irq = platform_get_irq_byname(pdev, irq_name);290 291 if (irq < 0)292 return irq;293 294 platform_set_drvdata(pdev, bd_rtc);295 296 ret = regmap_read(bd_rtc->regmap, hour_reg, &hr);297 298 if (ret) {299 dev_err(&pdev->dev, "Failed to reag RTC clock\n");300 return ret;301 }302 303 if (!(hr & BD70528_MASK_RTC_HOUR_24H)) {304 struct rtc_time t;305 306 ret = rtc_ops->read_time(&pdev->dev, &t);307 308 if (!ret)309 ret = rtc_ops->set_time(&pdev->dev, &t);310 311 if (ret) {312 dev_err(&pdev->dev,313 "Setting 24H clock for RTC failed\n");314 return ret;315 }316 }317 318 device_set_wakeup_capable(&pdev->dev, true);319 device_wakeup_enable(&pdev->dev);320 321 rtc = devm_rtc_allocate_device(&pdev->dev);322 if (IS_ERR(rtc)) {323 dev_err(&pdev->dev, "RTC device creation failed\n");324 return PTR_ERR(rtc);325 }326 327 rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;328 rtc->range_max = RTC_TIMESTAMP_END_2099;329 rtc->ops = rtc_ops;330 331 /* Request alarm IRQ prior to registerig the RTC */332 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, &alm_hndlr,333 IRQF_ONESHOT, "bd70528-rtc", rtc);334 if (ret)335 return ret;336 337 return devm_rtc_register_device(rtc);338}339 340static const struct platform_device_id bd718x7_rtc_id[] = {341 { "bd71828-rtc", ROHM_CHIP_TYPE_BD71828 },342 { "bd71815-rtc", ROHM_CHIP_TYPE_BD71815 },343 { },344};345MODULE_DEVICE_TABLE(platform, bd718x7_rtc_id);346 347static struct platform_driver bd70528_rtc = {348 .driver = {349 .name = "bd70528-rtc"350 },351 .probe = bd70528_probe,352 .id_table = bd718x7_rtc_id,353};354 355module_platform_driver(bd70528_rtc);356 357MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>");358MODULE_DESCRIPTION("ROHM BD71828 and BD71815 PMIC RTC driver");359MODULE_LICENSE("GPL");360MODULE_ALIAS("platform:bd70528-rtc");361