| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Real-time clock driver for MPC5121 |
| * |
| * Copyright 2007, Domen Puncer <domen.puncer@telargo.com> |
| * Copyright 2008, Freescale Semiconductor, Inc. All rights reserved. |
| * Copyright 2011, Dmitry Eremin-Solenikov |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/module.h> |
| #include <linux/rtc.h> |
| #include <linux/of.h> |
| #include <linux/of_address.h> |
| #include <linux/of_device.h> |
| #include <linux/of_irq.h> |
| #include <linux/of_platform.h> |
| #include <linux/io.h> |
| #include <linux/slab.h> |
| |
| struct mpc5121_rtc_regs { |
| u8 set_time; /* RTC + 0x00 */ |
| u8 hour_set; /* RTC + 0x01 */ |
| u8 minute_set; /* RTC + 0x02 */ |
| u8 second_set; /* RTC + 0x03 */ |
| |
| u8 set_date; /* RTC + 0x04 */ |
| u8 month_set; /* RTC + 0x05 */ |
| u8 weekday_set; /* RTC + 0x06 */ |
| u8 date_set; /* RTC + 0x07 */ |
| |
| u8 write_sw; /* RTC + 0x08 */ |
| u8 sw_set; /* RTC + 0x09 */ |
| u16 year_set; /* RTC + 0x0a */ |
| |
| u8 alm_enable; /* RTC + 0x0c */ |
| u8 alm_hour_set; /* RTC + 0x0d */ |
| u8 alm_min_set; /* RTC + 0x0e */ |
| u8 int_enable; /* RTC + 0x0f */ |
| |
| u8 reserved1; |
| u8 hour; /* RTC + 0x11 */ |
| u8 minute; /* RTC + 0x12 */ |
| u8 second; /* RTC + 0x13 */ |
| |
| u8 month; /* RTC + 0x14 */ |
| u8 wday_mday; /* RTC + 0x15 */ |
| u16 year; /* RTC + 0x16 */ |
| |
| u8 int_alm; /* RTC + 0x18 */ |
| u8 int_sw; /* RTC + 0x19 */ |
| u8 alm_status; /* RTC + 0x1a */ |
| u8 sw_minute; /* RTC + 0x1b */ |
| |
| u8 bus_error_1; /* RTC + 0x1c */ |
| u8 int_day; /* RTC + 0x1d */ |
| u8 int_min; /* RTC + 0x1e */ |
| u8 int_sec; /* RTC + 0x1f */ |
| |
| /* |
| * target_time: |
| * intended to be used for hibernation but hibernation |
| * does not work on silicon rev 1.5 so use it for non-volatile |
| * storage of offset between the actual_time register and linux |
| * time |
| */ |
| u32 target_time; /* RTC + 0x20 */ |
| /* |
| * actual_time: |
| * readonly time since VBAT_RTC was last connected |
| */ |
| u32 actual_time; /* RTC + 0x24 */ |
| u32 keep_alive; /* RTC + 0x28 */ |
| }; |
| |
| struct mpc5121_rtc_data { |
| unsigned irq; |
| unsigned irq_periodic; |
| struct mpc5121_rtc_regs __iomem *regs; |
| struct rtc_device *rtc; |
| struct rtc_wkalrm wkalarm; |
| }; |
| |
| /* |
| * Update second/minute/hour registers. |
| * |
| * This is just so alarm will work. |
| */ |
| static void mpc5121_rtc_update_smh(struct mpc5121_rtc_regs __iomem *regs, |
| struct rtc_time *tm) |
| { |
| out_8(®s->second_set, tm->tm_sec); |
| out_8(®s->minute_set, tm->tm_min); |
| out_8(®s->hour_set, tm->tm_hour); |
| |
| /* set time sequence */ |
| out_8(®s->set_time, 0x1); |
| out_8(®s->set_time, 0x3); |
| out_8(®s->set_time, 0x1); |
| out_8(®s->set_time, 0x0); |
| } |
| |
| static int mpc5121_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); |
| struct mpc5121_rtc_regs __iomem *regs = rtc->regs; |
| unsigned long now; |
| |
| /* |
| * linux time is actual_time plus the offset saved in target_time |
| */ |
| now = in_be32(®s->actual_time) + in_be32(®s->target_time); |
| |
| rtc_time64_to_tm(now, tm); |
| |
| /* |
| * update second minute hour registers |
| * so alarms will work |
| */ |
| mpc5121_rtc_update_smh(regs, tm); |
| |
| return 0; |
| } |
| |
| static int mpc5121_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); |
| struct mpc5121_rtc_regs __iomem *regs = rtc->regs; |
| unsigned long now; |
| |
| /* |
| * The actual_time register is read only so we write the offset |
| * between it and linux time to the target_time register. |
| */ |
| now = rtc_tm_to_time64(tm); |
| out_be32(®s->target_time, now - in_be32(®s->actual_time)); |
| |
| /* |
| * update second minute hour registers |
| * so alarms will work |
| */ |
| mpc5121_rtc_update_smh(regs, tm); |
| |
| return 0; |
| } |
| |
| static int mpc5200_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); |
| struct mpc5121_rtc_regs __iomem *regs = rtc->regs; |
| int tmp; |
| |
| tm->tm_sec = in_8(®s->second); |
| tm->tm_min = in_8(®s->minute); |
| |
| /* 12 hour format? */ |
| if (in_8(®s->hour) & 0x20) |
| tm->tm_hour = (in_8(®s->hour) >> 1) + |
| (in_8(®s->hour) & 1 ? 12 : 0); |
| else |
| tm->tm_hour = in_8(®s->hour); |
| |
| tmp = in_8(®s->wday_mday); |
| tm->tm_mday = tmp & 0x1f; |
| tm->tm_mon = in_8(®s->month) - 1; |
| tm->tm_year = in_be16(®s->year) - 1900; |
| tm->tm_wday = (tmp >> 5) % 7; |
| tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); |
| tm->tm_isdst = 0; |
| |
| return 0; |
| } |
| |
| static int mpc5200_rtc_set_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); |
| struct mpc5121_rtc_regs __iomem *regs = rtc->regs; |
| |
| mpc5121_rtc_update_smh(regs, tm); |
| |
| /* date */ |
| out_8(®s->month_set, tm->tm_mon + 1); |
| out_8(®s->weekday_set, tm->tm_wday ? tm->tm_wday : 7); |
| out_8(®s->date_set, tm->tm_mday); |
| out_be16(®s->year_set, tm->tm_year + 1900); |
| |
| /* set date sequence */ |
| out_8(®s->set_date, 0x1); |
| out_8(®s->set_date, 0x3); |
| out_8(®s->set_date, 0x1); |
| out_8(®s->set_date, 0x0); |
| |
| return 0; |
| } |
| |
| static int mpc5121_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) |
| { |
| struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); |
| struct mpc5121_rtc_regs __iomem *regs = rtc->regs; |
| |
| *alarm = rtc->wkalarm; |
| |
| alarm->pending = in_8(®s->alm_status); |
| |
| return 0; |
| } |
| |
| static int mpc5121_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) |
| { |
| struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); |
| struct mpc5121_rtc_regs __iomem *regs = rtc->regs; |
| |
| /* |
| * the alarm has no seconds so deal with it |
| */ |
| if (alarm->time.tm_sec) { |
| alarm->time.tm_sec = 0; |
| alarm->time.tm_min++; |
| if (alarm->time.tm_min >= 60) { |
| alarm->time.tm_min = 0; |
| alarm->time.tm_hour++; |
| if (alarm->time.tm_hour >= 24) |
| alarm->time.tm_hour = 0; |
| } |
| } |
| |
| alarm->time.tm_mday = -1; |
| alarm->time.tm_mon = -1; |
| alarm->time.tm_year = -1; |
| |
| out_8(®s->alm_min_set, alarm->time.tm_min); |
| out_8(®s->alm_hour_set, alarm->time.tm_hour); |
| |
| out_8(®s->alm_enable, alarm->enabled); |
| |
| rtc->wkalarm = *alarm; |
| return 0; |
| } |
| |
| static irqreturn_t mpc5121_rtc_handler(int irq, void *dev) |
| { |
| struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev); |
| struct mpc5121_rtc_regs __iomem *regs = rtc->regs; |
| |
| if (in_8(®s->int_alm)) { |
| /* acknowledge and clear status */ |
| out_8(®s->int_alm, 1); |
| out_8(®s->alm_status, 1); |
| |
| rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_AF); |
| return IRQ_HANDLED; |
| } |
| |
| return IRQ_NONE; |
| } |
| |
| static irqreturn_t mpc5121_rtc_handler_upd(int irq, void *dev) |
| { |
| struct mpc5121_rtc_data *rtc = dev_get_drvdata((struct device *)dev); |
| struct mpc5121_rtc_regs __iomem *regs = rtc->regs; |
| |
| if (in_8(®s->int_sec) && (in_8(®s->int_enable) & 0x1)) { |
| /* acknowledge */ |
| out_8(®s->int_sec, 1); |
| |
| rtc_update_irq(rtc->rtc, 1, RTC_IRQF | RTC_UF); |
| return IRQ_HANDLED; |
| } |
| |
| return IRQ_NONE; |
| } |
| |
| static int mpc5121_rtc_alarm_irq_enable(struct device *dev, |
| unsigned int enabled) |
| { |
| struct mpc5121_rtc_data *rtc = dev_get_drvdata(dev); |
| struct mpc5121_rtc_regs __iomem *regs = rtc->regs; |
| int val; |
| |
| if (enabled) |
| val = 1; |
| else |
| val = 0; |
| |
| out_8(®s->alm_enable, val); |
| rtc->wkalarm.enabled = val; |
| |
| return 0; |
| } |
| |
| static const struct rtc_class_ops mpc5121_rtc_ops = { |
| .read_time = mpc5121_rtc_read_time, |
| .set_time = mpc5121_rtc_set_time, |
| .read_alarm = mpc5121_rtc_read_alarm, |
| .set_alarm = mpc5121_rtc_set_alarm, |
| .alarm_irq_enable = mpc5121_rtc_alarm_irq_enable, |
| }; |
| |
| static const struct rtc_class_ops mpc5200_rtc_ops = { |
| .read_time = mpc5200_rtc_read_time, |
| .set_time = mpc5200_rtc_set_time, |
| .read_alarm = mpc5121_rtc_read_alarm, |
| .set_alarm = mpc5121_rtc_set_alarm, |
| .alarm_irq_enable = mpc5121_rtc_alarm_irq_enable, |
| }; |
| |
| static int mpc5121_rtc_probe(struct platform_device *op) |
| { |
| struct mpc5121_rtc_data *rtc; |
| int err = 0; |
| |
| rtc = devm_kzalloc(&op->dev, sizeof(*rtc), GFP_KERNEL); |
| if (!rtc) |
| return -ENOMEM; |
| |
| rtc->regs = devm_platform_ioremap_resource(op, 0); |
| if (IS_ERR(rtc->regs)) { |
| dev_err(&op->dev, "%s: couldn't map io space\n", __func__); |
| return -ENOSYS; |
| } |
| |
| device_init_wakeup(&op->dev, 1); |
| |
| platform_set_drvdata(op, rtc); |
| |
| rtc->irq = irq_of_parse_and_map(op->dev.of_node, 1); |
| err = devm_request_irq(&op->dev, rtc->irq, mpc5121_rtc_handler, 0, |
| "mpc5121-rtc", &op->dev); |
| if (err) { |
| dev_err(&op->dev, "%s: could not request irq: %i\n", |
| __func__, rtc->irq); |
| goto out_dispose; |
| } |
| |
| rtc->irq_periodic = irq_of_parse_and_map(op->dev.of_node, 0); |
| err = devm_request_irq(&op->dev, rtc->irq_periodic, |
| mpc5121_rtc_handler_upd, 0, "mpc5121-rtc_upd", |
| &op->dev); |
| if (err) { |
| dev_err(&op->dev, "%s: could not request irq: %i\n", |
| __func__, rtc->irq_periodic); |
| goto out_dispose2; |
| } |
| |
| rtc->rtc = devm_rtc_allocate_device(&op->dev); |
| if (IS_ERR(rtc->rtc)) { |
| err = PTR_ERR(rtc->rtc); |
| goto out_dispose2; |
| } |
| |
| rtc->rtc->ops = &mpc5200_rtc_ops; |
| rtc->rtc->uie_unsupported = 1; |
| rtc->rtc->range_min = RTC_TIMESTAMP_BEGIN_0000; |
| rtc->rtc->range_max = 65733206399ULL; /* 4052-12-31 23:59:59 */ |
| |
| if (of_device_is_compatible(op->dev.of_node, "fsl,mpc5121-rtc")) { |
| u32 ka; |
| ka = in_be32(&rtc->regs->keep_alive); |
| if (ka & 0x02) { |
| dev_warn(&op->dev, |
| "mpc5121-rtc: Battery or oscillator failure!\n"); |
| out_be32(&rtc->regs->keep_alive, ka); |
| } |
| rtc->rtc->ops = &mpc5121_rtc_ops; |
| /* |
| * This is a limitation of the driver that abuses the target |
| * time register, the actual maximum year for the mpc5121 is |
| * also 4052. |
| */ |
| rtc->rtc->range_min = 0; |
| rtc->rtc->range_max = U32_MAX; |
| } |
| |
| err = rtc_register_device(rtc->rtc); |
| if (err) |
| goto out_dispose2; |
| |
| return 0; |
| |
| out_dispose2: |
| irq_dispose_mapping(rtc->irq_periodic); |
| out_dispose: |
| irq_dispose_mapping(rtc->irq); |
| |
| return err; |
| } |
| |
| static int mpc5121_rtc_remove(struct platform_device *op) |
| { |
| struct mpc5121_rtc_data *rtc = platform_get_drvdata(op); |
| struct mpc5121_rtc_regs __iomem *regs = rtc->regs; |
| |
| /* disable interrupt, so there are no nasty surprises */ |
| out_8(®s->alm_enable, 0); |
| out_8(®s->int_enable, in_8(®s->int_enable) & ~0x1); |
| |
| irq_dispose_mapping(rtc->irq); |
| irq_dispose_mapping(rtc->irq_periodic); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_OF |
| static const struct of_device_id mpc5121_rtc_match[] = { |
| { .compatible = "fsl,mpc5121-rtc", }, |
| { .compatible = "fsl,mpc5200-rtc", }, |
| {}, |
| }; |
| MODULE_DEVICE_TABLE(of, mpc5121_rtc_match); |
| #endif |
| |
| static struct platform_driver mpc5121_rtc_driver = { |
| .driver = { |
| .name = "mpc5121-rtc", |
| .of_match_table = of_match_ptr(mpc5121_rtc_match), |
| }, |
| .probe = mpc5121_rtc_probe, |
| .remove = mpc5121_rtc_remove, |
| }; |
| |
| module_platform_driver(mpc5121_rtc_driver); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("John Rigby <jcrigby@gmail.com>"); |