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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Real-time clock driver for MPC51214 *5 * Copyright 2007, Domen Puncer <domen.puncer@telargo.com>6 * Copyright 2008, Freescale Semiconductor, Inc. All rights reserved.7 * Copyright 2011, Dmitry Eremin-Solenikov8 */9 10#include <linux/init.h>11#include <linux/module.h>12#include <linux/rtc.h>13#include <linux/of.h>14#include <linux/of_irq.h>15#include <linux/platform_device.h>16#include <linux/io.h>17#include <linux/slab.h>18 19struct mpc5121_rtc_regs {20 u8 set_time; /* RTC + 0x00 */21 u8 hour_set; /* RTC + 0x01 */22 u8 minute_set; /* RTC + 0x02 */23 u8 second_set; /* RTC + 0x03 */24 25 u8 set_date; /* RTC + 0x04 */26 u8 month_set; /* RTC + 0x05 */27 u8 weekday_set; /* RTC + 0x06 */28 u8 date_set; /* RTC + 0x07 */29 30 u8 write_sw; /* RTC + 0x08 */31 u8 sw_set; /* RTC + 0x09 */32 u16 year_set; /* RTC + 0x0a */33 34 u8 alm_enable; /* RTC + 0x0c */35 u8 alm_hour_set; /* RTC + 0x0d */36 u8 alm_min_set; /* RTC + 0x0e */37 u8 int_enable; /* RTC + 0x0f */38 39 u8 reserved1;40 u8 hour; /* RTC + 0x11 */41 u8 minute; /* RTC + 0x12 */42 u8 second; /* RTC + 0x13 */43 44 u8 month; /* RTC + 0x14 */45 u8 wday_mday; /* RTC + 0x15 */46 u16 year; /* RTC + 0x16 */47 48 u8 int_alm; /* RTC + 0x18 */49 u8 int_sw; /* RTC + 0x19 */50 u8 alm_status; /* RTC + 0x1a */51 u8 sw_minute; /* RTC + 0x1b */52 53 u8 bus_error_1; /* RTC + 0x1c */54 u8 int_day; /* RTC + 0x1d */55 u8 int_min; /* RTC + 0x1e */56 u8 int_sec; /* RTC + 0x1f */57 58 /*59 * target_time:60 * intended to be used for hibernation but hibernation61 * does not work on silicon rev 1.5 so use it for non-volatile62 * storage of offset between the actual_time register and linux63 * time64 */65 u32 target_time; /* RTC + 0x20 */66 /*67 * actual_time:68 * readonly time since VBAT_RTC was last connected69 */70 u32 actual_time; /* RTC + 0x24 */71 u32 keep_alive; /* RTC + 0x28 */72};73 74struct mpc5121_rtc_data {75 unsigned irq;76 unsigned irq_periodic;77 struct mpc5121_rtc_regs __iomem *regs;78 struct rtc_device *rtc;79 struct rtc_wkalrm wkalarm;80};81 82/*83 * Update second/minute/hour registers.84 *85 * This is just so alarm will work.86 */87static void mpc5121_rtc_update_smh(struct mpc5121_rtc_regs __iomem *regs,88 struct rtc_time *tm)89{90 out_8(®s->second_set, tm->tm_sec);91 out_8(®s->minute_set, tm->tm_min);92 out_8(®s->hour_set, tm->tm_hour);93 94 /* set time sequence */95 out_8(®s->set_time, 0x1);96 out_8(®s->set_time, 0x3);97 out_8(®s->set_time, 0x1);98 out_8(®s->set_time, 0x0);99}100 101static int mpc5121_rtc_read_time(struct device *dev, struct rtc_time *tm)102{103 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);104 struct mpc5121_rtc_regs __iomem *regs = rtc->regs;105 unsigned long now;106 107 /*108 * linux time is actual_time plus the offset saved in target_time109 */110 now = in_be32(®s->actual_time) + in_be32(®s->target_time);111 112 rtc_time64_to_tm(now, tm);113 114 /*115 * update second minute hour registers116 * so alarms will work117 */118 mpc5121_rtc_update_smh(regs, tm);119 120 return 0;121}122 123static int mpc5121_rtc_set_time(struct device *dev, struct rtc_time *tm)124{125 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);126 struct mpc5121_rtc_regs __iomem *regs = rtc->regs;127 unsigned long now;128 129 /*130 * The actual_time register is read only so we write the offset131 * between it and linux time to the target_time register.132 */133 now = rtc_tm_to_time64(tm);134 out_be32(®s->target_time, now - in_be32(®s->actual_time));135 136 /*137 * update second minute hour registers138 * so alarms will work139 */140 mpc5121_rtc_update_smh(regs, tm);141 142 return 0;143}144 145static int mpc5200_rtc_read_time(struct device *dev, struct rtc_time *tm)146{147 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);148 struct mpc5121_rtc_regs __iomem *regs = rtc->regs;149 int tmp;150 151 tm->tm_sec = in_8(®s->second);152 tm->tm_min = in_8(®s->minute);153 154 /* 12 hour format? */155 if (in_8(®s->hour) & 0x20)156 tm->tm_hour = (in_8(®s->hour) >> 1) +157 (in_8(®s->hour) & 1 ? 12 : 0);158 else159 tm->tm_hour = in_8(®s->hour);160 161 tmp = in_8(®s->wday_mday);162 tm->tm_mday = tmp & 0x1f;163 tm->tm_mon = in_8(®s->month) - 1;164 tm->tm_year = in_be16(®s->year) - 1900;165 tm->tm_wday = (tmp >> 5) % 7;166 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);167 tm->tm_isdst = 0;168 169 return 0;170}171 172static int mpc5200_rtc_set_time(struct device *dev, struct rtc_time *tm)173{174 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);175 struct mpc5121_rtc_regs __iomem *regs = rtc->regs;176 177 mpc5121_rtc_update_smh(regs, tm);178 179 /* date */180 out_8(®s->month_set, tm->tm_mon + 1);181 out_8(®s->weekday_set, tm->tm_wday ? tm->tm_wday : 7);182 out_8(®s->date_set, tm->tm_mday);183 out_be16(®s->year_set, tm->tm_year + 1900);184 185 /* set date sequence */186 out_8(®s->set_date, 0x1);187 out_8(®s->set_date, 0x3);188 out_8(®s->set_date, 0x1);189 out_8(®s->set_date, 0x0);190 191 return 0;192}193 194static int mpc5121_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)195{196 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);197 struct mpc5121_rtc_regs __iomem *regs = rtc->regs;198 199 *alarm = rtc->wkalarm;200 201 alarm->pending = in_8(®s->alm_status);202 203 return 0;204}205 206static int mpc5121_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)207{208 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);209 struct mpc5121_rtc_regs __iomem *regs = rtc->regs;210 211 alarm->time.tm_mday = -1;212 alarm->time.tm_mon = -1;213 alarm->time.tm_year = -1;214 215 out_8(®s->alm_min_set, alarm->time.tm_min);216 out_8(®s->alm_hour_set, alarm->time.tm_hour);217 218 out_8(®s->alm_enable, alarm->enabled);219 220 rtc->wkalarm = *alarm;221 return 0;222}223 224static irqreturn_t mpc5121_rtc_handler(int irq, void *dev)225{226 struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev);227 struct mpc5121_rtc_regs __iomem *regs = rtc->regs;228 229 if (in_8(®s->int_alm)) {230 /* acknowledge and clear status */231 out_8(®s->int_alm, 1);232 out_8(®s->alm_status, 1);233 234 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF);235 return IRQ_HANDLED;236 }237 238 return IRQ_NONE;239}240 241static irqreturn_t mpc5121_rtc_handler_upd(int irq, void *dev)242{243 struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev);244 struct mpc5121_rtc_regs __iomem *regs = rtc->regs;245 246 if (in_8(®s->int_sec) && (in_8(®s->int_enable) & 0x1)) {247 /* acknowledge */248 out_8(®s->int_sec, 1);249 250 rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_UF);251 return IRQ_HANDLED;252 }253 254 return IRQ_NONE;255}256 257static int mpc5121_rtc_alarm_irq_enable(struct device *dev,258 unsigned int enabled)259{260 struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev);261 struct mpc5121_rtc_regs __iomem *regs = rtc->regs;262 int val;263 264 if (enabled)265 val = 1;266 else267 val = 0;268 269 out_8(®s->alm_enable, val);270 rtc->wkalarm.enabled = val;271 272 return 0;273}274 275static const struct rtc_class_ops mpc5121_rtc_ops = {276 .read_time = mpc5121_rtc_read_time,277 .set_time = mpc5121_rtc_set_time,278 .read_alarm = mpc5121_rtc_read_alarm,279 .set_alarm = mpc5121_rtc_set_alarm,280 .alarm_irq_enable = mpc5121_rtc_alarm_irq_enable,281};282 283static const struct rtc_class_ops mpc5200_rtc_ops = {284 .read_time = mpc5200_rtc_read_time,285 .set_time = mpc5200_rtc_set_time,286 .read_alarm = mpc5121_rtc_read_alarm,287 .set_alarm = mpc5121_rtc_set_alarm,288 .alarm_irq_enable = mpc5121_rtc_alarm_irq_enable,289};290 291static int mpc5121_rtc_probe(struct platform_device *op)292{293 struct mpc5121_rtc_data *rtc;294 int err = 0;295 296 rtc = devm_kzalloc(&op->dev, sizeof(*rtc), GFP_KERNEL);297 if (!rtc)298 return -ENOMEM;299 300 rtc->regs = devm_platform_ioremap_resource(op, 0);301 if (IS_ERR(rtc->regs)) {302 dev_err(&op->dev, "%s: couldn't map io space\n", __func__);303 return PTR_ERR(rtc->regs);304 }305 306 device_init_wakeup(&op->dev, 1);307 308 platform_set_drvdata(op, rtc);309 310 rtc->irq = irq_of_parse_and_map(op->dev.of_node, 1);311 err = devm_request_irq(&op->dev, rtc->irq, mpc5121_rtc_handler, 0,312 "mpc5121-rtc", &op->dev);313 if (err) {314 dev_err(&op->dev, "%s: could not request irq: %i\n",315 __func__, rtc->irq);316 goto out_dispose;317 }318 319 rtc->irq_periodic = irq_of_parse_and_map(op->dev.of_node, 0);320 err = devm_request_irq(&op->dev, rtc->irq_periodic,321 mpc5121_rtc_handler_upd, 0, "mpc5121-rtc_upd",322 &op->dev);323 if (err) {324 dev_err(&op->dev, "%s: could not request irq: %i\n",325 __func__, rtc->irq_periodic);326 goto out_dispose2;327 }328 329 rtc->rtc = devm_rtc_allocate_device(&op->dev);330 if (IS_ERR(rtc->rtc)) {331 err = PTR_ERR(rtc->rtc);332 goto out_dispose2;333 }334 335 rtc->rtc->ops = &mpc5200_rtc_ops;336 set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->rtc->features);337 clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->rtc->features);338 rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_0000;339 rtc->rtc->range_max = 65733206399ULL; /* 4052-12-31 23:59:59 */340 341 if (of_device_is_compatible(op->dev.of_node, "fsl,mpc5121-rtc")) {342 u32 ka;343 ka = in_be32(&rtc->regs->keep_alive);344 if (ka & 0x02) {345 dev_warn(&op->dev,346 "mpc5121-rtc: Battery or oscillator failure!\n");347 out_be32(&rtc->regs->keep_alive, ka);348 }349 rtc->rtc->ops = &mpc5121_rtc_ops;350 /*351 * This is a limitation of the driver that abuses the target352 * time register, the actual maximum year for the mpc5121 is353 * also 4052.354 */355 rtc->rtc->range_min = 0;356 rtc->rtc->range_max = U32_MAX;357 }358 359 err = devm_rtc_register_device(rtc->rtc);360 if (err)361 goto out_dispose2;362 363 return 0;364 365out_dispose2:366 irq_dispose_mapping(rtc->irq_periodic);367out_dispose:368 irq_dispose_mapping(rtc->irq);369 370 return err;371}372 373static void mpc5121_rtc_remove(struct platform_device *op)374{375 struct mpc5121_rtc_data *rtc = platform_get_drvdata(op);376 struct mpc5121_rtc_regs __iomem *regs = rtc->regs;377 378 /* disable interrupt, so there are no nasty surprises */379 out_8(®s->alm_enable, 0);380 out_8(®s->int_enable, in_8(®s->int_enable) & ~0x1);381 382 irq_dispose_mapping(rtc->irq);383 irq_dispose_mapping(rtc->irq_periodic);384}385 386#ifdef CONFIG_OF387static const struct of_device_id mpc5121_rtc_match[] = {388 { .compatible = "fsl,mpc5121-rtc", },389 { .compatible = "fsl,mpc5200-rtc", },390 {},391};392MODULE_DEVICE_TABLE(of, mpc5121_rtc_match);393#endif394 395static struct platform_driver mpc5121_rtc_driver = {396 .driver = {397 .name = "mpc5121-rtc",398 .of_match_table = of_match_ptr(mpc5121_rtc_match),399 },400 .probe = mpc5121_rtc_probe,401 .remove_new = mpc5121_rtc_remove,402};403 404module_platform_driver(mpc5121_rtc_driver);405 406MODULE_DESCRIPTION("Freescale MPC5121 built-in RTC driver");407MODULE_LICENSE("GPL");408MODULE_AUTHOR("John Rigby <jcrigby@gmail.com>");409