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1// SPDX-License-Identifier: GPL-2.02/* drivers/rtc/rtc-goldfish.c3 *4 * Copyright (C) 2007 Google, Inc.5 * Copyright (C) 2017 Imagination Technologies Ltd.6 */7 8#include <linux/io.h>9#include <linux/module.h>10#include <linux/of.h>11#include <linux/platform_device.h>12#include <linux/rtc.h>13#include <linux/goldfish.h>14#include <clocksource/timer-goldfish.h>15 16struct goldfish_rtc {17 void __iomem *base;18 int irq;19 struct rtc_device *rtc;20};21 22static int goldfish_rtc_read_alarm(struct device *dev,23 struct rtc_wkalrm *alrm)24{25 u64 rtc_alarm;26 u64 rtc_alarm_low;27 u64 rtc_alarm_high;28 void __iomem *base;29 struct goldfish_rtc *rtcdrv;30 31 rtcdrv = dev_get_drvdata(dev);32 base = rtcdrv->base;33 34 rtc_alarm_low = gf_ioread32(base + TIMER_ALARM_LOW);35 rtc_alarm_high = gf_ioread32(base + TIMER_ALARM_HIGH);36 rtc_alarm = (rtc_alarm_high << 32) | rtc_alarm_low;37 38 do_div(rtc_alarm, NSEC_PER_SEC);39 memset(alrm, 0, sizeof(struct rtc_wkalrm));40 41 rtc_time64_to_tm(rtc_alarm, &alrm->time);42 43 if (gf_ioread32(base + TIMER_ALARM_STATUS))44 alrm->enabled = 1;45 else46 alrm->enabled = 0;47 48 return 0;49}50 51static int goldfish_rtc_set_alarm(struct device *dev,52 struct rtc_wkalrm *alrm)53{54 struct goldfish_rtc *rtcdrv;55 u64 rtc_alarm64;56 u64 rtc_status_reg;57 void __iomem *base;58 59 rtcdrv = dev_get_drvdata(dev);60 base = rtcdrv->base;61 62 if (alrm->enabled) {63 rtc_alarm64 = rtc_tm_to_time64(&alrm->time) * NSEC_PER_SEC;64 gf_iowrite32((rtc_alarm64 >> 32), base + TIMER_ALARM_HIGH);65 gf_iowrite32(rtc_alarm64, base + TIMER_ALARM_LOW);66 gf_iowrite32(1, base + TIMER_IRQ_ENABLED);67 } else {68 /*69 * if this function was called with enabled=070 * then it could mean that the application is71 * trying to cancel an ongoing alarm72 */73 rtc_status_reg = gf_ioread32(base + TIMER_ALARM_STATUS);74 if (rtc_status_reg)75 gf_iowrite32(1, base + TIMER_CLEAR_ALARM);76 }77 78 return 0;79}80 81static int goldfish_rtc_alarm_irq_enable(struct device *dev,82 unsigned int enabled)83{84 void __iomem *base;85 struct goldfish_rtc *rtcdrv;86 87 rtcdrv = dev_get_drvdata(dev);88 base = rtcdrv->base;89 90 if (enabled)91 gf_iowrite32(1, base + TIMER_IRQ_ENABLED);92 else93 gf_iowrite32(0, base + TIMER_IRQ_ENABLED);94 95 return 0;96}97 98static irqreturn_t goldfish_rtc_interrupt(int irq, void *dev_id)99{100 struct goldfish_rtc *rtcdrv = dev_id;101 void __iomem *base = rtcdrv->base;102 103 gf_iowrite32(1, base + TIMER_CLEAR_INTERRUPT);104 105 rtc_update_irq(rtcdrv->rtc, 1, RTC_IRQF | RTC_AF);106 107 return IRQ_HANDLED;108}109 110static int goldfish_rtc_read_time(struct device *dev, struct rtc_time *tm)111{112 struct goldfish_rtc *rtcdrv;113 void __iomem *base;114 u64 time_high;115 u64 time_low;116 u64 time;117 118 rtcdrv = dev_get_drvdata(dev);119 base = rtcdrv->base;120 121 time_low = gf_ioread32(base + TIMER_TIME_LOW);122 time_high = gf_ioread32(base + TIMER_TIME_HIGH);123 time = (time_high << 32) | time_low;124 125 do_div(time, NSEC_PER_SEC);126 127 rtc_time64_to_tm(time, tm);128 129 return 0;130}131 132static int goldfish_rtc_set_time(struct device *dev, struct rtc_time *tm)133{134 struct goldfish_rtc *rtcdrv;135 void __iomem *base;136 u64 now64;137 138 rtcdrv = dev_get_drvdata(dev);139 base = rtcdrv->base;140 141 now64 = rtc_tm_to_time64(tm) * NSEC_PER_SEC;142 gf_iowrite32((now64 >> 32), base + TIMER_TIME_HIGH);143 gf_iowrite32(now64, base + TIMER_TIME_LOW);144 145 return 0;146}147 148static const struct rtc_class_ops goldfish_rtc_ops = {149 .read_time = goldfish_rtc_read_time,150 .set_time = goldfish_rtc_set_time,151 .read_alarm = goldfish_rtc_read_alarm,152 .set_alarm = goldfish_rtc_set_alarm,153 .alarm_irq_enable = goldfish_rtc_alarm_irq_enable154};155 156static int goldfish_rtc_probe(struct platform_device *pdev)157{158 struct goldfish_rtc *rtcdrv;159 int err;160 161 rtcdrv = devm_kzalloc(&pdev->dev, sizeof(*rtcdrv), GFP_KERNEL);162 if (!rtcdrv)163 return -ENOMEM;164 165 platform_set_drvdata(pdev, rtcdrv);166 rtcdrv->base = devm_platform_ioremap_resource(pdev, 0);167 if (IS_ERR(rtcdrv->base))168 return PTR_ERR(rtcdrv->base);169 170 rtcdrv->irq = platform_get_irq(pdev, 0);171 if (rtcdrv->irq < 0)172 return -ENODEV;173 174 rtcdrv->rtc = devm_rtc_allocate_device(&pdev->dev);175 if (IS_ERR(rtcdrv->rtc))176 return PTR_ERR(rtcdrv->rtc);177 178 rtcdrv->rtc->ops = &goldfish_rtc_ops;179 rtcdrv->rtc->range_max = U64_MAX / NSEC_PER_SEC;180 181 err = devm_request_irq(&pdev->dev, rtcdrv->irq,182 goldfish_rtc_interrupt,183 0, pdev->name, rtcdrv);184 if (err)185 return err;186 187 return devm_rtc_register_device(rtcdrv->rtc);188}189 190static const struct of_device_id goldfish_rtc_of_match[] = {191 { .compatible = "google,goldfish-rtc", },192 {},193};194MODULE_DEVICE_TABLE(of, goldfish_rtc_of_match);195 196static struct platform_driver goldfish_rtc = {197 .probe = goldfish_rtc_probe,198 .driver = {199 .name = "goldfish_rtc",200 .of_match_table = goldfish_rtc_of_match,201 }202};203 204module_platform_driver(goldfish_rtc);205 206MODULE_DESCRIPTION("Android Goldfish Real Time Clock driver");207MODULE_LICENSE("GPL v2");208