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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * RTC driver for Maxim MAX89254 *5 * Copyright (C) 2009-2010 Marvell International Ltd.6 * Haojian Zhuang <haojian.zhuang@marvell.com>7 */8 9#include <linux/module.h>10#include <linux/i2c.h>11#include <linux/slab.h>12#include <linux/rtc.h>13#include <linux/platform_device.h>14#include <linux/mfd/max8925.h>15 16enum {17 RTC_SEC = 0,18 RTC_MIN,19 RTC_HOUR,20 RTC_WEEKDAY,21 RTC_DATE,22 RTC_MONTH,23 RTC_YEAR1,24 RTC_YEAR2,25};26 27#define MAX8925_RTC_SEC 0x0028#define MAX8925_RTC_MIN 0x0129#define MAX8925_RTC_HOUR 0x0230#define MAX8925_RTC_WEEKDAY 0x0331#define MAX8925_RTC_DATE 0x0432#define MAX8925_RTC_MONTH 0x0533#define MAX8925_RTC_YEAR1 0x0634#define MAX8925_RTC_YEAR2 0x0735#define MAX8925_ALARM0_SEC 0x0836#define MAX8925_ALARM0_MIN 0x0937#define MAX8925_ALARM0_HOUR 0x0a38#define MAX8925_ALARM0_WEEKDAY 0x0b39#define MAX8925_ALARM0_DATE 0x0c40#define MAX8925_ALARM0_MON 0x0d41#define MAX8925_ALARM0_YEAR1 0x0e42#define MAX8925_ALARM0_YEAR2 0x0f43#define MAX8925_ALARM1_SEC 0x1044#define MAX8925_ALARM1_MIN 0x1145#define MAX8925_ALARM1_HOUR 0x1246#define MAX8925_ALARM1_WEEKDAY 0x1347#define MAX8925_ALARM1_DATE 0x1448#define MAX8925_ALARM1_MON 0x1549#define MAX8925_ALARM1_YEAR1 0x1650#define MAX8925_ALARM1_YEAR2 0x1751#define MAX8925_RTC_CNTL 0x1b52#define MAX8925_RTC_STATUS 0x2053 54#define TIME_NUM 855#define ALARM_1SEC (1 << 7)56#define HOUR_12 (1 << 7)57#define HOUR_AM_PM (1 << 5)58#define ALARM0_IRQ (1 << 3)59#define ALARM1_IRQ (1 << 2)60#define ALARM0_STATUS (1 << 2)61#define ALARM1_STATUS (1 << 1)62 63 64struct max8925_rtc_info {65 struct rtc_device *rtc_dev;66 struct max8925_chip *chip;67 struct i2c_client *rtc;68 struct device *dev;69 int irq;70};71 72static irqreturn_t rtc_update_handler(int irq, void *data)73{74 struct max8925_rtc_info *info = (struct max8925_rtc_info *)data;75 76 /* disable ALARM0 except for 1SEC alarm */77 max8925_set_bits(info->rtc, MAX8925_ALARM0_CNTL, 0x7f, 0);78 rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF);79 return IRQ_HANDLED;80}81 82static int tm_calc(struct rtc_time *tm, unsigned char *buf, int len)83{84 if (len < TIME_NUM)85 return -EINVAL;86 tm->tm_year = (buf[RTC_YEAR2] >> 4) * 100087 + (buf[RTC_YEAR2] & 0xf) * 10088 + (buf[RTC_YEAR1] >> 4) * 1089 + (buf[RTC_YEAR1] & 0xf);90 tm->tm_year -= 1900;91 tm->tm_mon = ((buf[RTC_MONTH] >> 4) & 0x01) * 1092 + (buf[RTC_MONTH] & 0x0f);93 tm->tm_mday = ((buf[RTC_DATE] >> 4) & 0x03) * 1094 + (buf[RTC_DATE] & 0x0f);95 tm->tm_wday = buf[RTC_WEEKDAY] & 0x07;96 if (buf[RTC_HOUR] & HOUR_12) {97 tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x1) * 1098 + (buf[RTC_HOUR] & 0x0f);99 if (buf[RTC_HOUR] & HOUR_AM_PM)100 tm->tm_hour += 12;101 } else102 tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x03) * 10103 + (buf[RTC_HOUR] & 0x0f);104 tm->tm_min = ((buf[RTC_MIN] >> 4) & 0x7) * 10105 + (buf[RTC_MIN] & 0x0f);106 tm->tm_sec = ((buf[RTC_SEC] >> 4) & 0x7) * 10107 + (buf[RTC_SEC] & 0x0f);108 return 0;109}110 111static int data_calc(unsigned char *buf, struct rtc_time *tm, int len)112{113 unsigned char high, low;114 115 if (len < TIME_NUM)116 return -EINVAL;117 118 high = (tm->tm_year + 1900) / 1000;119 low = (tm->tm_year + 1900) / 100;120 low = low - high * 10;121 buf[RTC_YEAR2] = (high << 4) + low;122 high = (tm->tm_year + 1900) / 10;123 low = tm->tm_year + 1900;124 low = low - high * 10;125 high = high - (high / 10) * 10;126 buf[RTC_YEAR1] = (high << 4) + low;127 high = tm->tm_mon / 10;128 low = tm->tm_mon;129 low = low - high * 10;130 buf[RTC_MONTH] = (high << 4) + low;131 high = tm->tm_mday / 10;132 low = tm->tm_mday;133 low = low - high * 10;134 buf[RTC_DATE] = (high << 4) + low;135 buf[RTC_WEEKDAY] = tm->tm_wday;136 high = tm->tm_hour / 10;137 low = tm->tm_hour;138 low = low - high * 10;139 buf[RTC_HOUR] = (high << 4) + low;140 high = tm->tm_min / 10;141 low = tm->tm_min;142 low = low - high * 10;143 buf[RTC_MIN] = (high << 4) + low;144 high = tm->tm_sec / 10;145 low = tm->tm_sec;146 low = low - high * 10;147 buf[RTC_SEC] = (high << 4) + low;148 return 0;149}150 151static int max8925_rtc_read_time(struct device *dev, struct rtc_time *tm)152{153 struct max8925_rtc_info *info = dev_get_drvdata(dev);154 unsigned char buf[TIME_NUM];155 int ret;156 157 ret = max8925_bulk_read(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);158 if (ret < 0)159 goto out;160 ret = tm_calc(tm, buf, TIME_NUM);161out:162 return ret;163}164 165static int max8925_rtc_set_time(struct device *dev, struct rtc_time *tm)166{167 struct max8925_rtc_info *info = dev_get_drvdata(dev);168 unsigned char buf[TIME_NUM];169 int ret;170 171 ret = data_calc(buf, tm, TIME_NUM);172 if (ret < 0)173 goto out;174 ret = max8925_bulk_write(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf);175out:176 return ret;177}178 179static int max8925_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)180{181 struct max8925_rtc_info *info = dev_get_drvdata(dev);182 unsigned char buf[TIME_NUM];183 int ret;184 185 ret = max8925_bulk_read(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);186 if (ret < 0)187 goto out;188 ret = tm_calc(&alrm->time, buf, TIME_NUM);189 if (ret < 0)190 goto out;191 ret = max8925_reg_read(info->rtc, MAX8925_RTC_IRQ_MASK);192 if (ret < 0)193 goto out;194 if (ret & ALARM0_IRQ) {195 alrm->enabled = 0;196 } else {197 ret = max8925_reg_read(info->rtc, MAX8925_ALARM0_CNTL);198 if (ret < 0)199 goto out;200 if (!ret)201 alrm->enabled = 0;202 else203 alrm->enabled = 1;204 }205 ret = max8925_reg_read(info->rtc, MAX8925_RTC_STATUS);206 if (ret < 0)207 goto out;208 if (ret & ALARM0_STATUS)209 alrm->pending = 1;210 else211 alrm->pending = 0;212 return 0;213out:214 return ret;215}216 217static int max8925_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)218{219 struct max8925_rtc_info *info = dev_get_drvdata(dev);220 unsigned char buf[TIME_NUM];221 int ret;222 223 ret = data_calc(buf, &alrm->time, TIME_NUM);224 if (ret < 0)225 goto out;226 ret = max8925_bulk_write(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf);227 if (ret < 0)228 goto out;229 if (alrm->enabled)230 /* only enable alarm on year/month/day/hour/min/sec */231 ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x77);232 else233 ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x0);234out:235 return ret;236}237 238static const struct rtc_class_ops max8925_rtc_ops = {239 .read_time = max8925_rtc_read_time,240 .set_time = max8925_rtc_set_time,241 .read_alarm = max8925_rtc_read_alarm,242 .set_alarm = max8925_rtc_set_alarm,243};244 245static int max8925_rtc_probe(struct platform_device *pdev)246{247 struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);248 struct max8925_rtc_info *info;249 int ret;250 251 info = devm_kzalloc(&pdev->dev, sizeof(struct max8925_rtc_info),252 GFP_KERNEL);253 if (!info)254 return -ENOMEM;255 info->chip = chip;256 info->rtc = chip->rtc;257 info->dev = &pdev->dev;258 info->irq = platform_get_irq(pdev, 0);259 260 ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL,261 rtc_update_handler, IRQF_ONESHOT,262 "rtc-alarm0", info);263 if (ret < 0) {264 dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n",265 info->irq, ret);266 return ret;267 }268 269 dev_set_drvdata(&pdev->dev, info);270 /* XXX - isn't this redundant? */271 platform_set_drvdata(pdev, info);272 273 device_init_wakeup(&pdev->dev, 1);274 275 info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8925-rtc",276 &max8925_rtc_ops, THIS_MODULE);277 ret = PTR_ERR(info->rtc_dev);278 if (IS_ERR(info->rtc_dev)) {279 dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret);280 return ret;281 }282 283 return 0;284}285 286#ifdef CONFIG_PM_SLEEP287static int max8925_rtc_suspend(struct device *dev)288{289 struct platform_device *pdev = to_platform_device(dev);290 struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);291 292 if (device_may_wakeup(dev))293 chip->wakeup_flag |= 1 << MAX8925_IRQ_RTC_ALARM0;294 return 0;295}296static int max8925_rtc_resume(struct device *dev)297{298 struct platform_device *pdev = to_platform_device(dev);299 struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);300 301 if (device_may_wakeup(dev))302 chip->wakeup_flag &= ~(1 << MAX8925_IRQ_RTC_ALARM0);303 return 0;304}305#endif306 307static SIMPLE_DEV_PM_OPS(max8925_rtc_pm_ops, max8925_rtc_suspend, max8925_rtc_resume);308 309static struct platform_driver max8925_rtc_driver = {310 .driver = {311 .name = "max8925-rtc",312 .pm = &max8925_rtc_pm_ops,313 },314 .probe = max8925_rtc_probe,315};316 317module_platform_driver(max8925_rtc_driver);318 319MODULE_DESCRIPTION("Maxim MAX8925 RTC driver");320MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");321MODULE_LICENSE("GPL");322 323