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1// SPDX-License-Identifier: GPL-2.02 3/*4 * The RTC driver for Sunplus SP70215 *6 * Copyright (C) 2019 Sunplus Technology Inc., All rights reseerved.7 */8 9#include <linux/bitfield.h>10#include <linux/clk.h>11#include <linux/err.h>12#include <linux/io.h>13#include <linux/ktime.h>14#include <linux/module.h>15#include <linux/of.h>16#include <linux/platform_device.h>17#include <linux/reset.h>18#include <linux/rtc.h>19 20#define RTC_REG_NAME "rtc"21 22#define RTC_CTRL 0x4023#define TIMER_FREEZE_MASK_BIT BIT(5 + 16)24#define TIMER_FREEZE BIT(5)25#define DIS_SYS_RST_RTC_MASK_BIT BIT(4 + 16)26#define DIS_SYS_RST_RTC BIT(4)27#define RTC32K_MODE_RESET_MASK_BIT BIT(3 + 16)28#define RTC32K_MODE_RESET BIT(3)29#define ALARM_EN_OVERDUE_MASK_BIT BIT(2 + 16)30#define ALARM_EN_OVERDUE BIT(2)31#define ALARM_EN_PMC_MASK_BIT BIT(1 + 16)32#define ALARM_EN_PMC BIT(1)33#define ALARM_EN_MASK_BIT BIT(0 + 16)34#define ALARM_EN BIT(0)35#define RTC_TIMER_OUT 0x4436#define RTC_DIVIDER 0x4837#define RTC_TIMER_SET 0x4c38#define RTC_ALARM_SET 0x5039#define RTC_USER_DATA 0x5440#define RTC_RESET_RECORD 0x5841#define RTC_BATT_CHARGE_CTRL 0x5c42#define BAT_CHARGE_RSEL_MASK_BIT GENMASK(3 + 16, 2 + 16)43#define BAT_CHARGE_RSEL_MASK GENMASK(3, 2)44#define BAT_CHARGE_RSEL_2K_OHM FIELD_PREP(BAT_CHARGE_RSEL_MASK, 0)45#define BAT_CHARGE_RSEL_250_OHM FIELD_PREP(BAT_CHARGE_RSEL_MASK, 1)46#define BAT_CHARGE_RSEL_50_OHM FIELD_PREP(BAT_CHARGE_RSEL_MASK, 2)47#define BAT_CHARGE_RSEL_0_OHM FIELD_PREP(BAT_CHARGE_RSEL_MASK, 3)48#define BAT_CHARGE_DSEL_MASK_BIT BIT(1 + 16)49#define BAT_CHARGE_DSEL_MASK GENMASK(1, 1)50#define BAT_CHARGE_DSEL_ON FIELD_PREP(BAT_CHARGE_DSEL_MASK, 0)51#define BAT_CHARGE_DSEL_OFF FIELD_PREP(BAT_CHARGE_DSEL_MASK, 1)52#define BAT_CHARGE_EN_MASK_BIT BIT(0 + 16)53#define BAT_CHARGE_EN BIT(0)54#define RTC_TRIM_CTRL 0x6055 56struct sunplus_rtc {57 struct rtc_device *rtc;58 struct resource *res;59 struct clk *rtcclk;60 struct reset_control *rstc;61 void __iomem *reg_base;62 int irq;63};64 65static void sp_get_seconds(struct device *dev, unsigned long *secs)66{67 struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);68 69 *secs = (unsigned long)readl(sp_rtc->reg_base + RTC_TIMER_OUT);70}71 72static void sp_set_seconds(struct device *dev, unsigned long secs)73{74 struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);75 76 writel((u32)secs, sp_rtc->reg_base + RTC_TIMER_SET);77}78 79static int sp_rtc_read_time(struct device *dev, struct rtc_time *tm)80{81 unsigned long secs;82 83 sp_get_seconds(dev, &secs);84 rtc_time64_to_tm(secs, tm);85 86 return 0;87}88 89static int sp_rtc_set_time(struct device *dev, struct rtc_time *tm)90{91 unsigned long secs;92 93 secs = rtc_tm_to_time64(tm);94 dev_dbg(dev, "%s, secs = %lu\n", __func__, secs);95 sp_set_seconds(dev, secs);96 97 return 0;98}99 100static int sp_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)101{102 struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);103 unsigned long alarm_time;104 105 alarm_time = rtc_tm_to_time64(&alrm->time);106 dev_dbg(dev, "%s, alarm_time: %u\n", __func__, (u32)(alarm_time));107 writel((u32)alarm_time, sp_rtc->reg_base + RTC_ALARM_SET);108 109 return 0;110}111 112static int sp_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)113{114 struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);115 unsigned int alarm_time;116 117 alarm_time = readl(sp_rtc->reg_base + RTC_ALARM_SET);118 dev_dbg(dev, "%s, alarm_time: %u\n", __func__, alarm_time);119 120 if (alarm_time == 0)121 alrm->enabled = 0;122 else123 alrm->enabled = 1;124 125 rtc_time64_to_tm((unsigned long)(alarm_time), &alrm->time);126 127 return 0;128}129 130static int sp_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)131{132 struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);133 134 if (enabled)135 writel((TIMER_FREEZE_MASK_BIT | DIS_SYS_RST_RTC_MASK_BIT |136 RTC32K_MODE_RESET_MASK_BIT | ALARM_EN_OVERDUE_MASK_BIT |137 ALARM_EN_PMC_MASK_BIT | ALARM_EN_MASK_BIT) |138 (DIS_SYS_RST_RTC | ALARM_EN_OVERDUE | ALARM_EN_PMC | ALARM_EN),139 sp_rtc->reg_base + RTC_CTRL);140 else141 writel((ALARM_EN_OVERDUE_MASK_BIT | ALARM_EN_PMC_MASK_BIT | ALARM_EN_MASK_BIT) |142 0x0, sp_rtc->reg_base + RTC_CTRL);143 144 return 0;145}146 147static const struct rtc_class_ops sp_rtc_ops = {148 .read_time = sp_rtc_read_time,149 .set_time = sp_rtc_set_time,150 .set_alarm = sp_rtc_set_alarm,151 .read_alarm = sp_rtc_read_alarm,152 .alarm_irq_enable = sp_rtc_alarm_irq_enable,153};154 155static irqreturn_t sp_rtc_irq_handler(int irq, void *dev_id)156{157 struct platform_device *plat_dev = dev_id;158 struct sunplus_rtc *sp_rtc = dev_get_drvdata(&plat_dev->dev);159 160 rtc_update_irq(sp_rtc->rtc, 1, RTC_IRQF | RTC_AF);161 dev_dbg(&plat_dev->dev, "[RTC] ALARM INT\n");162 163 return IRQ_HANDLED;164}165 166/*167 * -------------------------------------------------------------------------------------168 * bat_charge_rsel bat_charge_dsel bat_charge_en Remarks169 * x x 0 Disable170 * 0 0 1 0.86mA (2K Ohm with diode)171 * 1 0 1 1.81mA (250 Ohm with diode)172 * 2 0 1 2.07mA (50 Ohm with diode)173 * 3 0 1 16.0mA (0 Ohm with diode)174 * 0 1 1 1.36mA (2K Ohm without diode)175 * 1 1 1 3.99mA (250 Ohm without diode)176 * 2 1 1 4.41mA (50 Ohm without diode)177 * 3 1 1 16.0mA (0 Ohm without diode)178 * -------------------------------------------------------------------------------------179 */180static void sp_rtc_set_trickle_charger(struct device dev)181{182 struct sunplus_rtc *sp_rtc = dev_get_drvdata(&dev);183 u32 ohms, rsel;184 u32 chargeable;185 186 if (of_property_read_u32(dev.of_node, "trickle-resistor-ohms", &ohms) ||187 of_property_read_u32(dev.of_node, "aux-voltage-chargeable", &chargeable)) {188 dev_warn(&dev, "battery charger disabled\n");189 return;190 }191 192 switch (ohms) {193 case 2000:194 rsel = BAT_CHARGE_RSEL_2K_OHM;195 break;196 case 250:197 rsel = BAT_CHARGE_RSEL_250_OHM;198 break;199 case 50:200 rsel = BAT_CHARGE_RSEL_50_OHM;201 break;202 case 0:203 rsel = BAT_CHARGE_RSEL_0_OHM;204 break;205 default:206 dev_err(&dev, "invalid charger resistor value (%d)\n", ohms);207 return;208 }209 210 writel(BAT_CHARGE_RSEL_MASK_BIT | rsel, sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);211 212 switch (chargeable) {213 case 0:214 writel(BAT_CHARGE_DSEL_MASK_BIT | BAT_CHARGE_DSEL_OFF,215 sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);216 break;217 case 1:218 writel(BAT_CHARGE_DSEL_MASK_BIT | BAT_CHARGE_DSEL_ON,219 sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);220 break;221 default:222 dev_err(&dev, "invalid aux-voltage-chargeable value (%d)\n", chargeable);223 return;224 }225 226 writel(BAT_CHARGE_EN_MASK_BIT | BAT_CHARGE_EN, sp_rtc->reg_base + RTC_BATT_CHARGE_CTRL);227}228 229static int sp_rtc_probe(struct platform_device *plat_dev)230{231 struct sunplus_rtc *sp_rtc;232 int ret;233 234 sp_rtc = devm_kzalloc(&plat_dev->dev, sizeof(*sp_rtc), GFP_KERNEL);235 if (!sp_rtc)236 return -ENOMEM;237 238 sp_rtc->reg_base = devm_platform_ioremap_resource_byname(plat_dev, RTC_REG_NAME);239 if (IS_ERR(sp_rtc->reg_base))240 return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->reg_base),241 "%s devm_ioremap_resource fail\n", RTC_REG_NAME);242 dev_dbg(&plat_dev->dev, "res = %pR, reg_base = %p\n",243 sp_rtc->res, sp_rtc->reg_base);244 245 sp_rtc->irq = platform_get_irq(plat_dev, 0);246 if (sp_rtc->irq < 0)247 return sp_rtc->irq;248 249 ret = devm_request_irq(&plat_dev->dev, sp_rtc->irq, sp_rtc_irq_handler,250 IRQF_TRIGGER_RISING, "rtc irq", plat_dev);251 if (ret)252 return dev_err_probe(&plat_dev->dev, ret, "devm_request_irq failed:\n");253 254 sp_rtc->rtcclk = devm_clk_get(&plat_dev->dev, NULL);255 if (IS_ERR(sp_rtc->rtcclk))256 return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->rtcclk),257 "devm_clk_get fail\n");258 259 sp_rtc->rstc = devm_reset_control_get_exclusive(&plat_dev->dev, NULL);260 if (IS_ERR(sp_rtc->rstc))261 return dev_err_probe(&plat_dev->dev, PTR_ERR(sp_rtc->rstc),262 "failed to retrieve reset controller\n");263 264 ret = clk_prepare_enable(sp_rtc->rtcclk);265 if (ret)266 goto free_clk;267 268 ret = reset_control_deassert(sp_rtc->rstc);269 if (ret)270 goto free_reset_assert;271 272 device_init_wakeup(&plat_dev->dev, 1);273 dev_set_drvdata(&plat_dev->dev, sp_rtc);274 275 sp_rtc->rtc = devm_rtc_allocate_device(&plat_dev->dev);276 if (IS_ERR(sp_rtc->rtc)) {277 ret = PTR_ERR(sp_rtc->rtc);278 goto free_reset_assert;279 }280 281 sp_rtc->rtc->range_max = U32_MAX;282 sp_rtc->rtc->range_min = 0;283 sp_rtc->rtc->ops = &sp_rtc_ops;284 285 ret = devm_rtc_register_device(sp_rtc->rtc);286 if (ret)287 goto free_reset_assert;288 289 /* Setup trickle charger */290 if (plat_dev->dev.of_node)291 sp_rtc_set_trickle_charger(plat_dev->dev);292 293 /* Keep RTC from system reset */294 writel(DIS_SYS_RST_RTC_MASK_BIT | DIS_SYS_RST_RTC, sp_rtc->reg_base + RTC_CTRL);295 296 return 0;297 298free_reset_assert:299 reset_control_assert(sp_rtc->rstc);300free_clk:301 clk_disable_unprepare(sp_rtc->rtcclk);302 303 return ret;304}305 306static void sp_rtc_remove(struct platform_device *plat_dev)307{308 struct sunplus_rtc *sp_rtc = dev_get_drvdata(&plat_dev->dev);309 310 device_init_wakeup(&plat_dev->dev, 0);311 reset_control_assert(sp_rtc->rstc);312 clk_disable_unprepare(sp_rtc->rtcclk);313}314 315#ifdef CONFIG_PM_SLEEP316static int sp_rtc_suspend(struct device *dev)317{318 struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);319 320 if (device_may_wakeup(dev))321 enable_irq_wake(sp_rtc->irq);322 323 return 0;324}325 326static int sp_rtc_resume(struct device *dev)327{328 struct sunplus_rtc *sp_rtc = dev_get_drvdata(dev);329 330 if (device_may_wakeup(dev))331 disable_irq_wake(sp_rtc->irq);332 333 return 0;334}335#endif336 337static const struct of_device_id sp_rtc_of_match[] = {338 { .compatible = "sunplus,sp7021-rtc" },339 { /* sentinel */ }340};341MODULE_DEVICE_TABLE(of, sp_rtc_of_match);342 343static SIMPLE_DEV_PM_OPS(sp_rtc_pm_ops, sp_rtc_suspend, sp_rtc_resume);344 345static struct platform_driver sp_rtc_driver = {346 .probe = sp_rtc_probe,347 .remove_new = sp_rtc_remove,348 .driver = {349 .name = "sp7021-rtc",350 .of_match_table = sp_rtc_of_match,351 .pm = &sp_rtc_pm_ops,352 },353};354module_platform_driver(sp_rtc_driver);355 356MODULE_AUTHOR("Vincent Shih <vincent.sunplus@gmail.com>");357MODULE_DESCRIPTION("Sunplus RTC driver");358MODULE_LICENSE("GPL v2");359 360