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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * rtc-rc5t583.c -- RICOH RC5T583 Real Time Clock4 *5 * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.6 * Author: Venu Byravarasu <vbyravarasu@nvidia.com>7 */8 9#include <linux/kernel.h>10#include <linux/errno.h>11#include <linux/init.h>12#include <linux/module.h>13#include <linux/types.h>14#include <linux/rtc.h>15#include <linux/bcd.h>16#include <linux/platform_device.h>17#include <linux/interrupt.h>18#include <linux/mfd/rc5t583.h>19 20struct rc5t583_rtc {21 struct rtc_device *rtc;22 /* To store the list of enabled interrupts, during system suspend */23 u32 irqen;24};25 26/* Total number of RTC registers needed to set time*/27#define NUM_TIME_REGS (RC5T583_RTC_YEAR - RC5T583_RTC_SEC + 1)28 29/* Total number of RTC registers needed to set Y-Alarm*/30#define NUM_YAL_REGS (RC5T583_RTC_AY_YEAR - RC5T583_RTC_AY_MIN + 1)31 32/* Set Y-Alarm interrupt */33#define SET_YAL BIT(5)34 35/* Get Y-Alarm interrupt status*/36#define GET_YAL_STATUS BIT(3)37 38static int rc5t583_rtc_alarm_irq_enable(struct device *dev, unsigned enabled)39{40 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);41 u8 val;42 43 /* Set Y-Alarm, based on 'enabled' */44 val = enabled ? SET_YAL : 0;45 46 return regmap_update_bits(rc5t583->regmap, RC5T583_RTC_CTL1, SET_YAL,47 val);48}49 50/*51 * Gets current rc5t583 RTC time and date parameters.52 *53 * The RTC's time/alarm representation is not what gmtime(3) requires54 * Linux to use:55 *56 * - Months are 1..12 vs Linux 0-1157 * - Years are 0..99 vs Linux 1900..N (we assume 21st century)58 */59static int rc5t583_rtc_read_time(struct device *dev, struct rtc_time *tm)60{61 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);62 u8 rtc_data[NUM_TIME_REGS];63 int ret;64 65 ret = regmap_bulk_read(rc5t583->regmap, RC5T583_RTC_SEC, rtc_data,66 NUM_TIME_REGS);67 if (ret < 0) {68 dev_err(dev, "RTC read time failed with err:%d\n", ret);69 return ret;70 }71 72 tm->tm_sec = bcd2bin(rtc_data[0]);73 tm->tm_min = bcd2bin(rtc_data[1]);74 tm->tm_hour = bcd2bin(rtc_data[2]);75 tm->tm_wday = bcd2bin(rtc_data[3]);76 tm->tm_mday = bcd2bin(rtc_data[4]);77 tm->tm_mon = bcd2bin(rtc_data[5]) - 1;78 tm->tm_year = bcd2bin(rtc_data[6]) + 100;79 80 return ret;81}82 83static int rc5t583_rtc_set_time(struct device *dev, struct rtc_time *tm)84{85 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);86 unsigned char rtc_data[NUM_TIME_REGS];87 int ret;88 89 rtc_data[0] = bin2bcd(tm->tm_sec);90 rtc_data[1] = bin2bcd(tm->tm_min);91 rtc_data[2] = bin2bcd(tm->tm_hour);92 rtc_data[3] = bin2bcd(tm->tm_wday);93 rtc_data[4] = bin2bcd(tm->tm_mday);94 rtc_data[5] = bin2bcd(tm->tm_mon + 1);95 rtc_data[6] = bin2bcd(tm->tm_year - 100);96 97 ret = regmap_bulk_write(rc5t583->regmap, RC5T583_RTC_SEC, rtc_data,98 NUM_TIME_REGS);99 if (ret < 0) {100 dev_err(dev, "RTC set time failed with error %d\n", ret);101 return ret;102 }103 104 return ret;105}106 107static int rc5t583_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)108{109 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);110 unsigned char alarm_data[NUM_YAL_REGS];111 u32 interrupt_enable;112 int ret;113 114 ret = regmap_bulk_read(rc5t583->regmap, RC5T583_RTC_AY_MIN, alarm_data,115 NUM_YAL_REGS);116 if (ret < 0) {117 dev_err(dev, "rtc_read_alarm error %d\n", ret);118 return ret;119 }120 121 alm->time.tm_sec = 0;122 alm->time.tm_min = bcd2bin(alarm_data[0]);123 alm->time.tm_hour = bcd2bin(alarm_data[1]);124 alm->time.tm_mday = bcd2bin(alarm_data[2]);125 alm->time.tm_mon = bcd2bin(alarm_data[3]) - 1;126 alm->time.tm_year = bcd2bin(alarm_data[4]) + 100;127 128 ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL1, &interrupt_enable);129 if (ret < 0)130 return ret;131 132 /* check if YALE is set */133 if (interrupt_enable & SET_YAL)134 alm->enabled = 1;135 136 return ret;137}138 139static int rc5t583_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)140{141 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);142 unsigned char alarm_data[NUM_YAL_REGS];143 int ret;144 145 ret = rc5t583_rtc_alarm_irq_enable(dev, 0);146 if (ret)147 return ret;148 149 alarm_data[0] = bin2bcd(alm->time.tm_min);150 alarm_data[1] = bin2bcd(alm->time.tm_hour);151 alarm_data[2] = bin2bcd(alm->time.tm_mday);152 alarm_data[3] = bin2bcd(alm->time.tm_mon + 1);153 alarm_data[4] = bin2bcd(alm->time.tm_year - 100);154 155 ret = regmap_bulk_write(rc5t583->regmap, RC5T583_RTC_AY_MIN, alarm_data,156 NUM_YAL_REGS);157 if (ret) {158 dev_err(dev, "rtc_set_alarm error %d\n", ret);159 return ret;160 }161 162 if (alm->enabled)163 ret = rc5t583_rtc_alarm_irq_enable(dev, 1);164 165 return ret;166}167 168static irqreturn_t rc5t583_rtc_interrupt(int irq, void *rtc)169{170 struct device *dev = rtc;171 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);172 struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);173 unsigned long events = 0;174 int ret;175 u32 rtc_reg;176 177 ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL2, &rtc_reg);178 if (ret < 0)179 return IRQ_NONE;180 181 if (rtc_reg & GET_YAL_STATUS) {182 events = RTC_IRQF | RTC_AF;183 /* clear pending Y-alarm interrupt bit */184 rtc_reg &= ~GET_YAL_STATUS;185 }186 187 ret = regmap_write(rc5t583->regmap, RC5T583_RTC_CTL2, rtc_reg);188 if (ret)189 return IRQ_NONE;190 191 /* Notify RTC core on event */192 rtc_update_irq(rc5t583_rtc->rtc, 1, events);193 194 return IRQ_HANDLED;195}196 197static const struct rtc_class_ops rc5t583_rtc_ops = {198 .read_time = rc5t583_rtc_read_time,199 .set_time = rc5t583_rtc_set_time,200 .read_alarm = rc5t583_rtc_read_alarm,201 .set_alarm = rc5t583_rtc_set_alarm,202 .alarm_irq_enable = rc5t583_rtc_alarm_irq_enable,203};204 205static int rc5t583_rtc_probe(struct platform_device *pdev)206{207 struct rc5t583 *rc5t583 = dev_get_drvdata(pdev->dev.parent);208 struct rc5t583_rtc *ricoh_rtc;209 struct rc5t583_platform_data *pmic_plat_data;210 int ret;211 int irq;212 213 ricoh_rtc = devm_kzalloc(&pdev->dev, sizeof(struct rc5t583_rtc),214 GFP_KERNEL);215 if (!ricoh_rtc)216 return -ENOMEM;217 218 platform_set_drvdata(pdev, ricoh_rtc);219 220 /* Clear pending interrupts */221 ret = regmap_write(rc5t583->regmap, RC5T583_RTC_CTL2, 0);222 if (ret < 0)223 return ret;224 225 /* clear RTC Adjust register */226 ret = regmap_write(rc5t583->regmap, RC5T583_RTC_ADJ, 0);227 if (ret < 0) {228 dev_err(&pdev->dev, "unable to program rtc_adjust reg\n");229 return -EBUSY;230 }231 232 pmic_plat_data = dev_get_platdata(rc5t583->dev);233 irq = pmic_plat_data->irq_base;234 if (irq <= 0) {235 dev_warn(&pdev->dev, "Wake up is not possible as irq = %d\n",236 irq);237 return ret;238 }239 240 irq += RC5T583_IRQ_YALE;241 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,242 rc5t583_rtc_interrupt, IRQF_TRIGGER_LOW,243 "rtc-rc5t583", &pdev->dev);244 if (ret < 0) {245 dev_err(&pdev->dev, "IRQ is not free.\n");246 return ret;247 }248 device_init_wakeup(&pdev->dev, 1);249 250 ricoh_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,251 &rc5t583_rtc_ops, THIS_MODULE);252 if (IS_ERR(ricoh_rtc->rtc)) {253 ret = PTR_ERR(ricoh_rtc->rtc);254 dev_err(&pdev->dev, "RTC device register: err %d\n", ret);255 return ret;256 }257 258 return 0;259}260 261/*262 * Disable rc5t583 RTC interrupts.263 * Sets status flag to free.264 */265static void rc5t583_rtc_remove(struct platform_device *pdev)266{267 struct rc5t583_rtc *rc5t583_rtc = platform_get_drvdata(pdev);268 269 rc5t583_rtc_alarm_irq_enable(&rc5t583_rtc->rtc->dev, 0);270}271 272#ifdef CONFIG_PM_SLEEP273static int rc5t583_rtc_suspend(struct device *dev)274{275 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);276 struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);277 int ret;278 279 /* Store current list of enabled interrupts*/280 ret = regmap_read(rc5t583->regmap, RC5T583_RTC_CTL1,281 &rc5t583_rtc->irqen);282 return ret;283}284 285static int rc5t583_rtc_resume(struct device *dev)286{287 struct rc5t583 *rc5t583 = dev_get_drvdata(dev->parent);288 struct rc5t583_rtc *rc5t583_rtc = dev_get_drvdata(dev);289 290 /* Restore list of enabled interrupts before suspend */291 return regmap_write(rc5t583->regmap, RC5T583_RTC_CTL1,292 rc5t583_rtc->irqen);293}294#endif295 296static SIMPLE_DEV_PM_OPS(rc5t583_rtc_pm_ops, rc5t583_rtc_suspend,297 rc5t583_rtc_resume);298 299static struct platform_driver rc5t583_rtc_driver = {300 .probe = rc5t583_rtc_probe,301 .remove_new = rc5t583_rtc_remove,302 .driver = {303 .name = "rtc-rc5t583",304 .pm = &rc5t583_rtc_pm_ops,305 },306};307 308module_platform_driver(rc5t583_rtc_driver);309MODULE_ALIAS("platform:rtc-rc5t583");310MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>");311MODULE_DESCRIPTION("RICOH 5T583 RTC driver");312MODULE_LICENSE("GPL v2");313