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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Real time clock driver for DA90524 *5 * Copyright(c) 2012 Dialog Semiconductor Ltd.6 *7 * Author: Dajun Dajun Chen <dajun.chen@diasemi.com>8 */9 10#include <linux/module.h>11#include <linux/platform_device.h>12#include <linux/rtc.h>13#include <linux/err.h>14#include <linux/delay.h>15 16#include <linux/mfd/da9052/da9052.h>17#include <linux/mfd/da9052/reg.h>18 19#define rtc_err(rtc, fmt, ...) \20 dev_err(rtc->da9052->dev, "%s: " fmt, __func__, ##__VA_ARGS__)21 22#define DA9052_GET_TIME_RETRIES 523 24struct da9052_rtc {25 struct rtc_device *rtc;26 struct da9052 *da9052;27};28 29static int da9052_rtc_enable_alarm(struct da9052_rtc *rtc, bool enable)30{31 int ret;32 if (enable) {33 ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,34 DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON,35 DA9052_ALARM_Y_ALARM_ON);36 if (ret != 0)37 rtc_err(rtc, "Failed to enable ALM: %d\n", ret);38 } else {39 ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,40 DA9052_ALARM_Y_ALARM_ON|DA9052_ALARM_Y_TICK_ON, 0);41 if (ret != 0)42 rtc_err(rtc, "Write error: %d\n", ret);43 }44 return ret;45}46 47static irqreturn_t da9052_rtc_irq(int irq, void *data)48{49 struct da9052_rtc *rtc = data;50 51 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);52 53 return IRQ_HANDLED;54}55 56static int da9052_read_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm)57{58 int ret;59 uint8_t v[2][5];60 int idx = 1;61 int timeout = DA9052_GET_TIME_RETRIES;62 63 ret = da9052_group_read(rtc->da9052, DA9052_ALARM_MI_REG, 5, &v[0][0]);64 if (ret) {65 rtc_err(rtc, "Failed to group read ALM: %d\n", ret);66 return ret;67 }68 69 do {70 ret = da9052_group_read(rtc->da9052,71 DA9052_ALARM_MI_REG, 5, &v[idx][0]);72 if (ret) {73 rtc_err(rtc, "Failed to group read ALM: %d\n", ret);74 return ret;75 }76 77 if (memcmp(&v[0][0], &v[1][0], 5) == 0) {78 rtc_tm->tm_year = (v[0][4] & DA9052_RTC_YEAR) + 100;79 rtc_tm->tm_mon = (v[0][3] & DA9052_RTC_MONTH) - 1;80 rtc_tm->tm_mday = v[0][2] & DA9052_RTC_DAY;81 rtc_tm->tm_hour = v[0][1] & DA9052_RTC_HOUR;82 rtc_tm->tm_min = v[0][0] & DA9052_RTC_MIN;83 rtc_tm->tm_sec = 0;84 85 ret = rtc_valid_tm(rtc_tm);86 return ret;87 }88 89 idx = (1-idx);90 msleep(20);91 92 } while (timeout--);93 94 rtc_err(rtc, "Timed out reading alarm time\n");95 96 return -EIO;97}98 99static int da9052_set_alarm(struct da9052_rtc *rtc, struct rtc_time *rtc_tm)100{101 struct da9052 *da9052 = rtc->da9052;102 unsigned long alm_time;103 int ret;104 uint8_t v[3];105 106 alm_time = rtc_tm_to_time64(rtc_tm);107 108 if (rtc_tm->tm_sec > 0) {109 alm_time += 60 - rtc_tm->tm_sec;110 rtc_time64_to_tm(alm_time, rtc_tm);111 }112 BUG_ON(rtc_tm->tm_sec); /* it will cause repeated irqs if not zero */113 114 rtc_tm->tm_year -= 100;115 rtc_tm->tm_mon += 1;116 117 ret = da9052_reg_update(da9052, DA9052_ALARM_MI_REG,118 DA9052_RTC_MIN, rtc_tm->tm_min);119 if (ret != 0) {120 rtc_err(rtc, "Failed to write ALRM MIN: %d\n", ret);121 return ret;122 }123 124 v[0] = rtc_tm->tm_hour;125 v[1] = rtc_tm->tm_mday;126 v[2] = rtc_tm->tm_mon;127 128 ret = da9052_group_write(da9052, DA9052_ALARM_H_REG, 3, v);129 if (ret < 0)130 return ret;131 132 ret = da9052_reg_update(da9052, DA9052_ALARM_Y_REG,133 DA9052_RTC_YEAR, rtc_tm->tm_year);134 if (ret != 0)135 rtc_err(rtc, "Failed to write ALRM YEAR: %d\n", ret);136 137 return ret;138}139 140static int da9052_rtc_get_alarm_status(struct da9052_rtc *rtc)141{142 int ret;143 144 ret = da9052_reg_read(rtc->da9052, DA9052_ALARM_Y_REG);145 if (ret < 0) {146 rtc_err(rtc, "Failed to read ALM: %d\n", ret);147 return ret;148 }149 150 return !!(ret&DA9052_ALARM_Y_ALARM_ON);151}152 153static int da9052_rtc_read_time(struct device *dev, struct rtc_time *rtc_tm)154{155 struct da9052_rtc *rtc = dev_get_drvdata(dev);156 int ret;157 uint8_t v[2][6];158 int idx = 1;159 int timeout = DA9052_GET_TIME_RETRIES;160 161 ret = da9052_group_read(rtc->da9052, DA9052_COUNT_S_REG, 6, &v[0][0]);162 if (ret) {163 rtc_err(rtc, "Failed to read RTC time : %d\n", ret);164 return ret;165 }166 167 do {168 ret = da9052_group_read(rtc->da9052,169 DA9052_COUNT_S_REG, 6, &v[idx][0]);170 if (ret) {171 rtc_err(rtc, "Failed to read RTC time : %d\n", ret);172 return ret;173 }174 175 if (memcmp(&v[0][0], &v[1][0], 6) == 0) {176 rtc_tm->tm_year = (v[0][5] & DA9052_RTC_YEAR) + 100;177 rtc_tm->tm_mon = (v[0][4] & DA9052_RTC_MONTH) - 1;178 rtc_tm->tm_mday = v[0][3] & DA9052_RTC_DAY;179 rtc_tm->tm_hour = v[0][2] & DA9052_RTC_HOUR;180 rtc_tm->tm_min = v[0][1] & DA9052_RTC_MIN;181 rtc_tm->tm_sec = v[0][0] & DA9052_RTC_SEC;182 183 return 0;184 }185 186 idx = (1-idx);187 msleep(20);188 189 } while (timeout--);190 191 rtc_err(rtc, "Timed out reading time\n");192 193 return -EIO;194}195 196static int da9052_rtc_set_time(struct device *dev, struct rtc_time *tm)197{198 struct da9052_rtc *rtc;199 uint8_t v[6];200 int ret;201 202 /* DA9052 only has 6 bits for year - to represent 2000-2063 */203 if ((tm->tm_year < 100) || (tm->tm_year > 163))204 return -EINVAL;205 206 rtc = dev_get_drvdata(dev);207 208 v[0] = tm->tm_sec;209 v[1] = tm->tm_min;210 v[2] = tm->tm_hour;211 v[3] = tm->tm_mday;212 v[4] = tm->tm_mon + 1;213 v[5] = tm->tm_year - 100;214 215 ret = da9052_group_write(rtc->da9052, DA9052_COUNT_S_REG, 6, v);216 if (ret < 0)217 rtc_err(rtc, "failed to set RTC time: %d\n", ret);218 return ret;219}220 221static int da9052_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)222{223 int ret;224 struct rtc_time *tm = &alrm->time;225 struct da9052_rtc *rtc = dev_get_drvdata(dev);226 227 ret = da9052_read_alarm(rtc, tm);228 if (ret < 0) {229 rtc_err(rtc, "failed to read RTC alarm: %d\n", ret);230 return ret;231 }232 233 alrm->enabled = da9052_rtc_get_alarm_status(rtc);234 return 0;235}236 237static int da9052_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)238{239 int ret;240 struct rtc_time *tm = &alrm->time;241 struct da9052_rtc *rtc = dev_get_drvdata(dev);242 243 /* DA9052 only has 6 bits for year - to represent 2000-2063 */244 if ((tm->tm_year < 100) || (tm->tm_year > 163))245 return -EINVAL;246 247 ret = da9052_rtc_enable_alarm(rtc, 0);248 if (ret < 0)249 return ret;250 251 ret = da9052_set_alarm(rtc, tm);252 if (ret < 0)253 return ret;254 255 ret = da9052_rtc_enable_alarm(rtc, 1);256 return ret;257}258 259static int da9052_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)260{261 struct da9052_rtc *rtc = dev_get_drvdata(dev);262 263 return da9052_rtc_enable_alarm(rtc, enabled);264}265 266static const struct rtc_class_ops da9052_rtc_ops = {267 .read_time = da9052_rtc_read_time,268 .set_time = da9052_rtc_set_time,269 .read_alarm = da9052_rtc_read_alarm,270 .set_alarm = da9052_rtc_set_alarm,271 .alarm_irq_enable = da9052_rtc_alarm_irq_enable,272};273 274static int da9052_rtc_probe(struct platform_device *pdev)275{276 struct da9052_rtc *rtc;277 int ret;278 279 rtc = devm_kzalloc(&pdev->dev, sizeof(struct da9052_rtc), GFP_KERNEL);280 if (!rtc)281 return -ENOMEM;282 283 rtc->da9052 = dev_get_drvdata(pdev->dev.parent);284 platform_set_drvdata(pdev, rtc);285 286 ret = da9052_reg_write(rtc->da9052, DA9052_BBAT_CONT_REG, 0xFE);287 if (ret < 0) {288 rtc_err(rtc,289 "Failed to setup RTC battery charging: %d\n", ret);290 return ret;291 }292 293 ret = da9052_reg_update(rtc->da9052, DA9052_ALARM_Y_REG,294 DA9052_ALARM_Y_TICK_ON, 0);295 if (ret != 0)296 rtc_err(rtc, "Failed to disable TICKS: %d\n", ret);297 298 device_init_wakeup(&pdev->dev, true);299 rtc->rtc = devm_rtc_allocate_device(&pdev->dev);300 if (IS_ERR(rtc->rtc))301 return PTR_ERR(rtc->rtc);302 303 rtc->rtc->ops = &da9052_rtc_ops;304 rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000;305 rtc->rtc->range_max = RTC_TIMESTAMP_END_2063;306 307 ret = devm_rtc_register_device(rtc->rtc);308 if (ret)309 return ret;310 311 ret = da9052_request_irq(rtc->da9052, DA9052_IRQ_ALARM, "ALM",312 da9052_rtc_irq, rtc);313 if (ret != 0) {314 rtc_err(rtc, "irq registration failed: %d\n", ret);315 return ret;316 }317 318 return 0;319}320 321static struct platform_driver da9052_rtc_driver = {322 .probe = da9052_rtc_probe,323 .driver = {324 .name = "da9052-rtc",325 },326};327 328module_platform_driver(da9052_rtc_driver);329 330MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>");331MODULE_DESCRIPTION("RTC driver for Dialog DA9052 PMIC");332MODULE_LICENSE("GPL");333MODULE_ALIAS("platform:da9052-rtc");334