diff options
Diffstat (limited to 'drivers/rtc/rtc-mpc5121.c')
| -rw-r--r-- | drivers/rtc/rtc-mpc5121.c | 411 |
1 files changed, 411 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mpc5121.c b/drivers/rtc/rtc-mpc5121.c new file mode 100644 index 000000000..6d7656a75 --- /dev/null +++ b/drivers/rtc/rtc-mpc5121.c @@ -0,0 +1,411 @@ +// 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; + + 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 PTR_ERR(rtc->regs); + } + + 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; + set_bit(RTC_FEATURE_ALARM_RES_MINUTE, rtc->rtc->features); + clear_bit(RTC_FEATURE_UPDATE_INTERRUPT, rtc->rtc->features); + 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 = devm_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>"); |