diff options
Diffstat (limited to 'drivers/rtc/rtc-tps65910.c')
| -rw-r--r-- | drivers/rtc/rtc-tps65910.c | 337 |
1 files changed, 337 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-tps65910.c b/drivers/rtc/rtc-tps65910.c new file mode 100644 index 000000000..f42aa2b2d --- /dev/null +++ b/drivers/rtc/rtc-tps65910.c @@ -0,0 +1,337 @@ +/* + * rtc-tps65910.c -- TPS65910 Real Time Clock interface + * + * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. + * Author: Venu Byravarasu <vbyravarasu@nvidia.com> + * + * Based on original TI driver rtc-twl.c + * Copyright (C) 2007 MontaVista Software, Inc + * Author: Alexandre Rusev <source@mvista.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/rtc.h> +#include <linux/bcd.h> +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/mfd/tps65910.h> + +struct tps65910_rtc { + struct rtc_device *rtc; + int irq; +}; + +/* Total number of RTC registers needed to set time*/ +#define NUM_TIME_REGS (TPS65910_YEARS - TPS65910_SECONDS + 1) + +static int tps65910_rtc_alarm_irq_enable(struct device *dev, unsigned enabled) +{ + struct tps65910 *tps = dev_get_drvdata(dev->parent); + u8 val = 0; + + if (enabled) + val = TPS65910_RTC_INTERRUPTS_IT_ALARM; + + return regmap_write(tps->regmap, TPS65910_RTC_INTERRUPTS, val); +} + +/* + * Gets current tps65910 RTC time and date parameters. + * + * The RTC's time/alarm representation is not what gmtime(3) requires + * Linux to use: + * + * - Months are 1..12 vs Linux 0-11 + * - Years are 0..99 vs Linux 1900..N (we assume 21st century) + */ +static int tps65910_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + unsigned char rtc_data[NUM_TIME_REGS]; + struct tps65910 *tps = dev_get_drvdata(dev->parent); + int ret; + + /* Copy RTC counting registers to static registers or latches */ + ret = regmap_update_bits(tps->regmap, TPS65910_RTC_CTRL, + TPS65910_RTC_CTRL_GET_TIME, TPS65910_RTC_CTRL_GET_TIME); + if (ret < 0) { + dev_err(dev, "RTC CTRL reg update failed with err:%d\n", ret); + return ret; + } + + ret = regmap_bulk_read(tps->regmap, TPS65910_SECONDS, rtc_data, + NUM_TIME_REGS); + if (ret < 0) { + dev_err(dev, "reading from RTC failed with err:%d\n", ret); + return ret; + } + + tm->tm_sec = bcd2bin(rtc_data[0]); + tm->tm_min = bcd2bin(rtc_data[1]); + tm->tm_hour = bcd2bin(rtc_data[2]); + tm->tm_mday = bcd2bin(rtc_data[3]); + tm->tm_mon = bcd2bin(rtc_data[4]) - 1; + tm->tm_year = bcd2bin(rtc_data[5]) + 100; + + return ret; +} + +static int tps65910_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + unsigned char rtc_data[NUM_TIME_REGS]; + struct tps65910 *tps = dev_get_drvdata(dev->parent); + int ret; + + rtc_data[0] = bin2bcd(tm->tm_sec); + rtc_data[1] = bin2bcd(tm->tm_min); + rtc_data[2] = bin2bcd(tm->tm_hour); + rtc_data[3] = bin2bcd(tm->tm_mday); + rtc_data[4] = bin2bcd(tm->tm_mon + 1); + rtc_data[5] = bin2bcd(tm->tm_year - 100); + + /* Stop RTC while updating the RTC time registers */ + ret = regmap_update_bits(tps->regmap, TPS65910_RTC_CTRL, + TPS65910_RTC_CTRL_STOP_RTC, 0); + if (ret < 0) { + dev_err(dev, "RTC stop failed with err:%d\n", ret); + return ret; + } + + /* update all the time registers in one shot */ + ret = regmap_bulk_write(tps->regmap, TPS65910_SECONDS, rtc_data, + NUM_TIME_REGS); + if (ret < 0) { + dev_err(dev, "rtc_set_time error %d\n", ret); + return ret; + } + + /* Start back RTC */ + ret = regmap_update_bits(tps->regmap, TPS65910_RTC_CTRL, + TPS65910_RTC_CTRL_STOP_RTC, 1); + if (ret < 0) + dev_err(dev, "RTC start failed with err:%d\n", ret); + + return ret; +} + +/* + * Gets current tps65910 RTC alarm time. + */ +static int tps65910_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) +{ + unsigned char alarm_data[NUM_TIME_REGS]; + u32 int_val; + struct tps65910 *tps = dev_get_drvdata(dev->parent); + int ret; + + ret = regmap_bulk_read(tps->regmap, TPS65910_SECONDS, alarm_data, + NUM_TIME_REGS); + if (ret < 0) { + dev_err(dev, "rtc_read_alarm error %d\n", ret); + return ret; + } + + alm->time.tm_sec = bcd2bin(alarm_data[0]); + alm->time.tm_min = bcd2bin(alarm_data[1]); + alm->time.tm_hour = bcd2bin(alarm_data[2]); + alm->time.tm_mday = bcd2bin(alarm_data[3]); + alm->time.tm_mon = bcd2bin(alarm_data[4]) - 1; + alm->time.tm_year = bcd2bin(alarm_data[5]) + 100; + + ret = regmap_read(tps->regmap, TPS65910_RTC_INTERRUPTS, &int_val); + if (ret < 0) + return ret; + + if (int_val & TPS65910_RTC_INTERRUPTS_IT_ALARM) + alm->enabled = 1; + + return ret; +} + +static int tps65910_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) +{ + unsigned char alarm_data[NUM_TIME_REGS]; + struct tps65910 *tps = dev_get_drvdata(dev->parent); + int ret; + + ret = tps65910_rtc_alarm_irq_enable(dev, 0); + if (ret) + return ret; + + alarm_data[0] = bin2bcd(alm->time.tm_sec); + alarm_data[1] = bin2bcd(alm->time.tm_min); + alarm_data[2] = bin2bcd(alm->time.tm_hour); + alarm_data[3] = bin2bcd(alm->time.tm_mday); + alarm_data[4] = bin2bcd(alm->time.tm_mon + 1); + alarm_data[5] = bin2bcd(alm->time.tm_year - 100); + + /* update all the alarm registers in one shot */ + ret = regmap_bulk_write(tps->regmap, TPS65910_ALARM_SECONDS, + alarm_data, NUM_TIME_REGS); + if (ret) { + dev_err(dev, "rtc_set_alarm error %d\n", ret); + return ret; + } + + if (alm->enabled) + ret = tps65910_rtc_alarm_irq_enable(dev, 1); + + return ret; +} + +static irqreturn_t tps65910_rtc_interrupt(int irq, void *rtc) +{ + struct device *dev = rtc; + unsigned long events = 0; + struct tps65910 *tps = dev_get_drvdata(dev->parent); + struct tps65910_rtc *tps_rtc = dev_get_drvdata(dev); + int ret; + u32 rtc_reg; + + ret = regmap_read(tps->regmap, TPS65910_RTC_STATUS, &rtc_reg); + if (ret) + return IRQ_NONE; + + if (rtc_reg & TPS65910_RTC_STATUS_ALARM) + events = RTC_IRQF | RTC_AF; + + ret = regmap_write(tps->regmap, TPS65910_RTC_STATUS, rtc_reg); + if (ret) + return IRQ_NONE; + + /* Notify RTC core on event */ + rtc_update_irq(tps_rtc->rtc, 1, events); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops tps65910_rtc_ops = { + .read_time = tps65910_rtc_read_time, + .set_time = tps65910_rtc_set_time, + .read_alarm = tps65910_rtc_read_alarm, + .set_alarm = tps65910_rtc_set_alarm, + .alarm_irq_enable = tps65910_rtc_alarm_irq_enable, +}; + +static int tps65910_rtc_probe(struct platform_device *pdev) +{ + struct tps65910 *tps65910 = NULL; + struct tps65910_rtc *tps_rtc = NULL; + int ret; + int irq; + u32 rtc_reg; + + tps65910 = dev_get_drvdata(pdev->dev.parent); + + tps_rtc = devm_kzalloc(&pdev->dev, sizeof(struct tps65910_rtc), + GFP_KERNEL); + if (!tps_rtc) + return -ENOMEM; + + /* Clear pending interrupts */ + ret = regmap_read(tps65910->regmap, TPS65910_RTC_STATUS, &rtc_reg); + if (ret < 0) + return ret; + + ret = regmap_write(tps65910->regmap, TPS65910_RTC_STATUS, rtc_reg); + if (ret < 0) + return ret; + + dev_dbg(&pdev->dev, "Enabling rtc-tps65910.\n"); + + /* Enable RTC digital power domain */ + ret = regmap_update_bits(tps65910->regmap, TPS65910_DEVCTRL, + DEVCTRL_RTC_PWDN_MASK, 0 << DEVCTRL_RTC_PWDN_SHIFT); + if (ret < 0) + return ret; + + rtc_reg = TPS65910_RTC_CTRL_STOP_RTC; + ret = regmap_write(tps65910->regmap, TPS65910_RTC_CTRL, rtc_reg); + if (ret < 0) + return ret; + + platform_set_drvdata(pdev, tps_rtc); + + irq = platform_get_irq(pdev, 0); + if (irq <= 0) { + dev_warn(&pdev->dev, "Wake up is not possible as irq = %d\n", + irq); + return -ENXIO; + } + + ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, + tps65910_rtc_interrupt, IRQF_TRIGGER_LOW | IRQF_EARLY_RESUME, + dev_name(&pdev->dev), &pdev->dev); + if (ret < 0) { + dev_err(&pdev->dev, "IRQ is not free.\n"); + return ret; + } + tps_rtc->irq = irq; + device_set_wakeup_capable(&pdev->dev, 1); + + tps_rtc->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, + &tps65910_rtc_ops, THIS_MODULE); + if (IS_ERR(tps_rtc->rtc)) { + ret = PTR_ERR(tps_rtc->rtc); + dev_err(&pdev->dev, "RTC device register: err %d\n", ret); + return ret; + } + + return 0; +} + +/* + * Disable tps65910 RTC interrupts. + * Sets status flag to free. + */ +static int tps65910_rtc_remove(struct platform_device *pdev) +{ + tps65910_rtc_alarm_irq_enable(&pdev->dev, 0); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int tps65910_rtc_suspend(struct device *dev) +{ + struct tps65910_rtc *tps_rtc = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + enable_irq_wake(tps_rtc->irq); + return 0; +} + +static int tps65910_rtc_resume(struct device *dev) +{ + struct tps65910_rtc *tps_rtc = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + disable_irq_wake(tps_rtc->irq); + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(tps65910_rtc_pm_ops, tps65910_rtc_suspend, + tps65910_rtc_resume); + +static struct platform_driver tps65910_rtc_driver = { + .probe = tps65910_rtc_probe, + .remove = tps65910_rtc_remove, + .driver = { + .name = "tps65910-rtc", + .pm = &tps65910_rtc_pm_ops, + }, +}; + +module_platform_driver(tps65910_rtc_driver); +MODULE_ALIAS("platform:rtc-tps65910"); +MODULE_AUTHOR("Venu Byravarasu <vbyravarasu@nvidia.com>"); +MODULE_LICENSE("GPL"); |