diff options
Diffstat (limited to 'drivers/rtc/rtc-mpc5121.c')
| -rw-r--r-- | drivers/rtc/rtc-mpc5121.c | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-mpc5121.c b/drivers/rtc/rtc-mpc5121.c new file mode 100644 index 00000000000..4313ca03a96 --- /dev/null +++ b/drivers/rtc/rtc-mpc5121.c @@ -0,0 +1,387 @@ +/* + * Real-time clock driver for MPC5121 + * + * Copyright 2007, Domen Puncer <domen.puncer@telargo.com> + * Copyright 2008, Freescale Semiconductor, Inc. All rights reserved. + * + * 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> + +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 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 int mpc5121_rtc_update_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; + + val = in_8(®s->int_enable); + + if (enabled) + val = (val & ~0x8) | 0x1; + else + val &= ~0x1; + + out_8(®s->int_enable, 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, + .update_irq_enable = mpc5121_rtc_update_irq_enable, +}; + +static int __devinit mpc5121_rtc_probe(struct of_device *op, + const struct of_device_id *match) +{ + struct mpc5121_rtc_data *rtc; + int err = 0; + u32 ka; + + rtc = kzalloc(sizeof(*rtc), GFP_KERNEL); + if (!rtc) + return -ENOMEM; + + rtc->regs = of_iomap(op->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->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->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; + } + + 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); + 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 of_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", }, + {}, +}; + +static struct of_platform_driver mpc5121_rtc_driver = { + .owner = THIS_MODULE, + .name = "mpc5121-rtc", + .match_table = mpc5121_rtc_match, + .probe = mpc5121_rtc_probe, + .remove = __devexit_p(mpc5121_rtc_remove), +}; + +static int __init mpc5121_rtc_init(void) +{ + return of_register_platform_driver(&mpc5121_rtc_driver); +} +module_init(mpc5121_rtc_init); + +static void __exit mpc5121_rtc_exit(void) +{ + of_unregister_platform_driver(&mpc5121_rtc_driver); +} +module_exit(mpc5121_rtc_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("John Rigby <jcrigby@gmail.com>"); |