/* * 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 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/init.h> #include <linux/module.h> #include <linux/rtc.h> #include <linux/of_device.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_time_to_tm(now, tm); /* * update second minute hour registers * so alarms will work */ mpc5121_rtc_update_smh(regs, tm); return rtc_valid_tm(tm); } 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; int ret; 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. */ ret = rtc_tm_to_time(tm, &now); if (ret == 0) 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 __devinit mpc5121_rtc_probe(struct platform_device *op) { struct mpc5121_rtc_data *rtc; int err = 0; rtc = kzalloc(sizeof(*rtc), GFP_KERNEL); if (!rtc) return -ENOMEM; rtc->regs = of_iomap(op->dev.of_node, 0); if (!rtc->regs) { dev_err(&op->dev, "%s: couldn't map io space\n", __func__); err = -ENOSYS; goto out_free; } device_init_wakeup(&op->dev, 1); dev_set_drvdata(&op->dev, rtc); rtc->irq = irq_of_parse_and_map(op->dev.of_node, 1); err = request_irq(rtc->irq, mpc5121_rtc_handler, IRQF_DISABLED, "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 = request_irq(rtc->irq_periodic, mpc5121_rtc_handler_upd, IRQF_DISABLED, "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; } 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 = rtc_device_register("mpc5121-rtc", &op->dev, &mpc5121_rtc_ops, THIS_MODULE); } else { rtc->rtc = rtc_device_register("mpc5200-rtc", &op->dev, &mpc5200_rtc_ops, THIS_MODULE); } if (IS_ERR(rtc->rtc)) { err = PTR_ERR(rtc->rtc); goto out_free_irq; } return 0; out_free_irq: free_irq(rtc->irq_periodic, &op->dev); out_dispose2: irq_dispose_mapping(rtc->irq_periodic); free_irq(rtc->irq, &op->dev); out_dispose: irq_dispose_mapping(rtc->irq); iounmap(rtc->regs); out_free: kfree(rtc); return err; } static int __devexit mpc5121_rtc_remove(struct platform_device *op) { struct mpc5121_rtc_data *rtc = dev_get_drvdata(&op->dev); 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); rtc_device_unregister(rtc->rtc); iounmap(rtc->regs); free_irq(rtc->irq, &op->dev); free_irq(rtc->irq_periodic, &op->dev); irq_dispose_mapping(rtc->irq); irq_dispose_mapping(rtc->irq_periodic); dev_set_drvdata(&op->dev, NULL); kfree(rtc); return 0; } static struct of_device_id mpc5121_rtc_match[] __devinitdata = { { .compatible = "fsl,mpc5121-rtc", }, { .compatible = "fsl,mpc5200-rtc", }, {}, }; static struct platform_driver mpc5121_rtc_driver = { .driver = { .name = "mpc5121-rtc", .owner = THIS_MODULE, .of_match_table = mpc5121_rtc_match, }, .probe = mpc5121_rtc_probe, .remove = __devexit_p(mpc5121_rtc_remove), }; module_platform_driver(mpc5121_rtc_driver); MODULE_LICENSE("GPL"); MODULE_AUTHOR("John Rigby <jcrigby@gmail.com>");