| /* |
| * Real Time Clock driver for Freescale MC13XXX PMIC |
| * |
| * (C) 2009 Sascha Hauer, Pengutronix |
| * (C) 2009 Uwe Kleine-Koenig, Pengutronix |
| * |
| * 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/mfd/mc13xxx.h> |
| #include <linux/platform_device.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| #include <linux/rtc.h> |
| |
| #define DRIVER_NAME "mc13xxx-rtc" |
| |
| #define MC13XXX_RTCTOD 20 |
| #define MC13XXX_RTCTODA 21 |
| #define MC13XXX_RTCDAY 22 |
| #define MC13XXX_RTCDAYA 23 |
| |
| struct mc13xxx_rtc { |
| struct rtc_device *rtc; |
| struct mc13xxx *mc13xxx; |
| int valid; |
| }; |
| |
| static int mc13xxx_rtc_irq_enable_unlocked(struct device *dev, |
| unsigned int enabled, int irq) |
| { |
| struct mc13xxx_rtc *priv = dev_get_drvdata(dev); |
| int (*func)(struct mc13xxx *mc13xxx, int irq); |
| |
| if (!priv->valid) |
| return -ENODATA; |
| |
| func = enabled ? mc13xxx_irq_unmask : mc13xxx_irq_mask; |
| return func(priv->mc13xxx, irq); |
| } |
| |
| static int mc13xxx_rtc_irq_enable(struct device *dev, |
| unsigned int enabled, int irq) |
| { |
| struct mc13xxx_rtc *priv = dev_get_drvdata(dev); |
| int ret; |
| |
| mc13xxx_lock(priv->mc13xxx); |
| |
| ret = mc13xxx_rtc_irq_enable_unlocked(dev, enabled, irq); |
| |
| mc13xxx_unlock(priv->mc13xxx); |
| |
| return ret; |
| } |
| |
| static int mc13xxx_rtc_read_time(struct device *dev, struct rtc_time *tm) |
| { |
| struct mc13xxx_rtc *priv = dev_get_drvdata(dev); |
| unsigned int seconds, days1, days2; |
| unsigned long s1970; |
| int ret; |
| |
| mc13xxx_lock(priv->mc13xxx); |
| |
| if (!priv->valid) { |
| ret = -ENODATA; |
| goto out; |
| } |
| |
| ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days1); |
| if (unlikely(ret)) |
| goto out; |
| |
| ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTOD, &seconds); |
| if (unlikely(ret)) |
| goto out; |
| |
| ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days2); |
| out: |
| mc13xxx_unlock(priv->mc13xxx); |
| |
| if (ret) |
| return ret; |
| |
| if (days2 == days1 + 1) { |
| if (seconds >= 86400 / 2) |
| days2 = days1; |
| else |
| days1 = days2; |
| } |
| |
| if (days1 != days2) |
| return -EIO; |
| |
| s1970 = days1 * 86400 + seconds; |
| |
| rtc_time_to_tm(s1970, tm); |
| |
| return rtc_valid_tm(tm); |
| } |
| |
| static int mc13xxx_rtc_set_mmss(struct device *dev, unsigned long secs) |
| { |
| struct mc13xxx_rtc *priv = dev_get_drvdata(dev); |
| unsigned int seconds, days; |
| unsigned int alarmseconds; |
| int ret; |
| |
| seconds = secs % 86400; |
| days = secs / 86400; |
| |
| mc13xxx_lock(priv->mc13xxx); |
| |
| /* |
| * temporarily invalidate alarm to prevent triggering it when the day is |
| * already updated while the time isn't yet. |
| */ |
| ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTODA, &alarmseconds); |
| if (unlikely(ret)) |
| goto out; |
| |
| if (alarmseconds < 86400) { |
| ret = mc13xxx_reg_write(priv->mc13xxx, |
| MC13XXX_RTCTODA, 0x1ffff); |
| if (unlikely(ret)) |
| goto out; |
| } |
| |
| /* |
| * write seconds=0 to prevent a day switch between writing days |
| * and seconds below |
| */ |
| ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCTOD, 0); |
| if (unlikely(ret)) |
| goto out; |
| |
| ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCDAY, days); |
| if (unlikely(ret)) |
| goto out; |
| |
| ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCTOD, seconds); |
| if (unlikely(ret)) |
| goto out; |
| |
| /* restore alarm */ |
| if (alarmseconds < 86400) { |
| ret = mc13xxx_reg_write(priv->mc13xxx, |
| MC13XXX_RTCTODA, alarmseconds); |
| if (unlikely(ret)) |
| goto out; |
| } |
| |
| ret = mc13xxx_irq_ack(priv->mc13xxx, MC13XXX_IRQ_RTCRST); |
| if (unlikely(ret)) |
| goto out; |
| |
| ret = mc13xxx_irq_unmask(priv->mc13xxx, MC13XXX_IRQ_RTCRST); |
| out: |
| priv->valid = !ret; |
| |
| mc13xxx_unlock(priv->mc13xxx); |
| |
| return ret; |
| } |
| |
| static int mc13xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) |
| { |
| struct mc13xxx_rtc *priv = dev_get_drvdata(dev); |
| unsigned seconds, days; |
| unsigned long s1970; |
| int enabled, pending; |
| int ret; |
| |
| mc13xxx_lock(priv->mc13xxx); |
| |
| ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTODA, &seconds); |
| if (unlikely(ret)) |
| goto out; |
| if (seconds >= 86400) { |
| ret = -ENODATA; |
| goto out; |
| } |
| |
| ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days); |
| if (unlikely(ret)) |
| goto out; |
| |
| ret = mc13xxx_irq_status(priv->mc13xxx, MC13XXX_IRQ_TODA, |
| &enabled, &pending); |
| |
| out: |
| mc13xxx_unlock(priv->mc13xxx); |
| |
| if (ret) |
| return ret; |
| |
| alarm->enabled = enabled; |
| alarm->pending = pending; |
| |
| s1970 = days * 86400 + seconds; |
| |
| rtc_time_to_tm(s1970, &alarm->time); |
| dev_dbg(dev, "%s: %lu\n", __func__, s1970); |
| |
| return 0; |
| } |
| |
| static int mc13xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) |
| { |
| struct mc13xxx_rtc *priv = dev_get_drvdata(dev); |
| unsigned long s1970; |
| unsigned seconds, days; |
| int ret; |
| |
| mc13xxx_lock(priv->mc13xxx); |
| |
| /* disable alarm to prevent false triggering */ |
| ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCTODA, 0x1ffff); |
| if (unlikely(ret)) |
| goto out; |
| |
| ret = mc13xxx_irq_ack(priv->mc13xxx, MC13XXX_IRQ_TODA); |
| if (unlikely(ret)) |
| goto out; |
| |
| ret = rtc_tm_to_time(&alarm->time, &s1970); |
| if (unlikely(ret)) |
| goto out; |
| |
| dev_dbg(dev, "%s: o%2.s %lu\n", __func__, alarm->enabled ? "n" : "ff", |
| s1970); |
| |
| ret = mc13xxx_rtc_irq_enable_unlocked(dev, alarm->enabled, |
| MC13XXX_IRQ_TODA); |
| if (unlikely(ret)) |
| goto out; |
| |
| seconds = s1970 % 86400; |
| days = s1970 / 86400; |
| |
| ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCDAYA, days); |
| if (unlikely(ret)) |
| goto out; |
| |
| ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCTODA, seconds); |
| |
| out: |
| mc13xxx_unlock(priv->mc13xxx); |
| |
| return ret; |
| } |
| |
| static irqreturn_t mc13xxx_rtc_alarm_handler(int irq, void *dev) |
| { |
| struct mc13xxx_rtc *priv = dev; |
| struct mc13xxx *mc13xxx = priv->mc13xxx; |
| |
| dev_dbg(&priv->rtc->dev, "Alarm\n"); |
| |
| rtc_update_irq(priv->rtc, 1, RTC_IRQF | RTC_AF); |
| |
| mc13xxx_irq_ack(mc13xxx, irq); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static irqreturn_t mc13xxx_rtc_update_handler(int irq, void *dev) |
| { |
| struct mc13xxx_rtc *priv = dev; |
| struct mc13xxx *mc13xxx = priv->mc13xxx; |
| |
| dev_dbg(&priv->rtc->dev, "1HZ\n"); |
| |
| rtc_update_irq(priv->rtc, 1, RTC_IRQF | RTC_UF); |
| |
| mc13xxx_irq_ack(mc13xxx, irq); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int mc13xxx_rtc_alarm_irq_enable(struct device *dev, |
| unsigned int enabled) |
| { |
| return mc13xxx_rtc_irq_enable(dev, enabled, MC13XXX_IRQ_TODA); |
| } |
| |
| static const struct rtc_class_ops mc13xxx_rtc_ops = { |
| .read_time = mc13xxx_rtc_read_time, |
| .set_mmss = mc13xxx_rtc_set_mmss, |
| .read_alarm = mc13xxx_rtc_read_alarm, |
| .set_alarm = mc13xxx_rtc_set_alarm, |
| .alarm_irq_enable = mc13xxx_rtc_alarm_irq_enable, |
| }; |
| |
| static irqreturn_t mc13xxx_rtc_reset_handler(int irq, void *dev) |
| { |
| struct mc13xxx_rtc *priv = dev; |
| struct mc13xxx *mc13xxx = priv->mc13xxx; |
| |
| dev_dbg(&priv->rtc->dev, "RTCRST\n"); |
| priv->valid = 0; |
| |
| mc13xxx_irq_mask(mc13xxx, irq); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static int __init mc13xxx_rtc_probe(struct platform_device *pdev) |
| { |
| int ret; |
| struct mc13xxx_rtc *priv; |
| struct mc13xxx *mc13xxx; |
| int rtcrst_pending; |
| |
| priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); |
| if (!priv) |
| return -ENOMEM; |
| |
| mc13xxx = dev_get_drvdata(pdev->dev.parent); |
| priv->mc13xxx = mc13xxx; |
| |
| platform_set_drvdata(pdev, priv); |
| |
| mc13xxx_lock(mc13xxx); |
| |
| ret = mc13xxx_irq_request(mc13xxx, MC13XXX_IRQ_RTCRST, |
| mc13xxx_rtc_reset_handler, DRIVER_NAME, priv); |
| if (ret) |
| goto err_reset_irq_request; |
| |
| ret = mc13xxx_irq_status(mc13xxx, MC13XXX_IRQ_RTCRST, |
| NULL, &rtcrst_pending); |
| if (ret) |
| goto err_reset_irq_status; |
| |
| priv->valid = !rtcrst_pending; |
| |
| ret = mc13xxx_irq_request_nounmask(mc13xxx, MC13XXX_IRQ_1HZ, |
| mc13xxx_rtc_update_handler, DRIVER_NAME, priv); |
| if (ret) |
| goto err_update_irq_request; |
| |
| ret = mc13xxx_irq_request_nounmask(mc13xxx, MC13XXX_IRQ_TODA, |
| mc13xxx_rtc_alarm_handler, DRIVER_NAME, priv); |
| if (ret) |
| goto err_alarm_irq_request; |
| |
| mc13xxx_unlock(mc13xxx); |
| |
| priv->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, |
| &mc13xxx_rtc_ops, THIS_MODULE); |
| if (IS_ERR(priv->rtc)) { |
| ret = PTR_ERR(priv->rtc); |
| |
| mc13xxx_lock(mc13xxx); |
| |
| mc13xxx_irq_free(mc13xxx, MC13XXX_IRQ_TODA, priv); |
| err_alarm_irq_request: |
| |
| mc13xxx_irq_free(mc13xxx, MC13XXX_IRQ_1HZ, priv); |
| err_update_irq_request: |
| |
| err_reset_irq_status: |
| |
| mc13xxx_irq_free(mc13xxx, MC13XXX_IRQ_RTCRST, priv); |
| err_reset_irq_request: |
| |
| mc13xxx_unlock(mc13xxx); |
| |
| platform_set_drvdata(pdev, NULL); |
| } |
| |
| return ret; |
| } |
| |
| static int __exit mc13xxx_rtc_remove(struct platform_device *pdev) |
| { |
| struct mc13xxx_rtc *priv = platform_get_drvdata(pdev); |
| |
| mc13xxx_lock(priv->mc13xxx); |
| |
| mc13xxx_irq_free(priv->mc13xxx, MC13XXX_IRQ_TODA, priv); |
| mc13xxx_irq_free(priv->mc13xxx, MC13XXX_IRQ_1HZ, priv); |
| mc13xxx_irq_free(priv->mc13xxx, MC13XXX_IRQ_RTCRST, priv); |
| |
| mc13xxx_unlock(priv->mc13xxx); |
| |
| platform_set_drvdata(pdev, NULL); |
| |
| return 0; |
| } |
| |
| static const struct platform_device_id mc13xxx_rtc_idtable[] = { |
| { |
| .name = "mc13783-rtc", |
| }, { |
| .name = "mc13892-rtc", |
| }, { |
| .name = "mc34708-rtc", |
| }, |
| { /* sentinel */ } |
| }; |
| MODULE_DEVICE_TABLE(platform, mc13xxx_rtc_idtable); |
| |
| static struct platform_driver mc13xxx_rtc_driver = { |
| .id_table = mc13xxx_rtc_idtable, |
| .remove = __exit_p(mc13xxx_rtc_remove), |
| .driver = { |
| .name = DRIVER_NAME, |
| .owner = THIS_MODULE, |
| }, |
| }; |
| |
| module_platform_driver_probe(mc13xxx_rtc_driver, &mc13xxx_rtc_probe); |
| |
| MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>"); |
| MODULE_DESCRIPTION("RTC driver for Freescale MC13XXX PMIC"); |
| MODULE_LICENSE("GPL v2"); |