diff options
Diffstat (limited to 'drivers/rtc/rtc-as3722.c')
| -rw-r--r-- | drivers/rtc/rtc-as3722.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-as3722.c b/drivers/rtc/rtc-as3722.c new file mode 100644 index 000000000000..9cfa8170a2d6 --- /dev/null +++ b/drivers/rtc/rtc-as3722.c @@ -0,0 +1,275 @@ +/* + * rtc-as3722.c - Real Time Clock driver for ams AS3722 PMICs + * + * Copyright (C) 2013 ams AG + * Copyright (c) 2013, NVIDIA Corporation. All rights reserved. + * + * Author: Florian Lobmaier <florian.lobmaier@ams.com> + * Author: Laxman Dewangan <ldewangan@nvidia.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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/bcd.h> +#include <linux/completion.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/ioctl.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mfd/as3722.h> +#include <linux/platform_device.h> +#include <linux/rtc.h> +#include <linux/time.h> + +#define AS3722_RTC_START_YEAR 2000 +struct as3722_rtc { + struct rtc_device *rtc; + struct device *dev; + struct as3722 *as3722; + int alarm_irq; + bool irq_enable; +}; + +static void as3722_time_to_reg(u8 *rbuff, struct rtc_time *tm) +{ + rbuff[0] = bin2bcd(tm->tm_sec); + rbuff[1] = bin2bcd(tm->tm_min); + rbuff[2] = bin2bcd(tm->tm_hour); + rbuff[3] = bin2bcd(tm->tm_mday); + rbuff[4] = bin2bcd(tm->tm_mon); + rbuff[5] = bin2bcd(tm->tm_year - (AS3722_RTC_START_YEAR - 1900)); +} + +static void as3722_reg_to_time(u8 *rbuff, struct rtc_time *tm) +{ + tm->tm_sec = bcd2bin(rbuff[0] & 0x7F); + tm->tm_min = bcd2bin(rbuff[1] & 0x7F); + tm->tm_hour = bcd2bin(rbuff[2] & 0x3F); + tm->tm_mday = bcd2bin(rbuff[3] & 0x3F); + tm->tm_mon = bcd2bin(rbuff[4] & 0x1F); + tm->tm_year = (AS3722_RTC_START_YEAR - 1900) + bcd2bin(rbuff[5] & 0x7F); + return; +} + +static int as3722_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev); + struct as3722 *as3722 = as3722_rtc->as3722; + u8 as_time_array[6]; + int ret; + + ret = as3722_block_read(as3722, AS3722_RTC_SECOND_REG, + 6, as_time_array); + if (ret < 0) { + dev_err(dev, "RTC_SECOND reg block read failed %d\n", ret); + return ret; + } + as3722_reg_to_time(as_time_array, tm); + return 0; +} + +static int as3722_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev); + struct as3722 *as3722 = as3722_rtc->as3722; + u8 as_time_array[6]; + int ret; + + if (tm->tm_year < (AS3722_RTC_START_YEAR - 1900)) + return -EINVAL; + + as3722_time_to_reg(as_time_array, tm); + ret = as3722_block_write(as3722, AS3722_RTC_SECOND_REG, 6, + as_time_array); + if (ret < 0) + dev_err(dev, "RTC_SECOND reg block write failed %d\n", ret); + return ret; +} + +static int as3722_rtc_alarm_irq_enable(struct device *dev, + unsigned int enabled) +{ + struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev); + + if (enabled && !as3722_rtc->irq_enable) { + enable_irq(as3722_rtc->alarm_irq); + as3722_rtc->irq_enable = true; + } else if (!enabled && as3722_rtc->irq_enable) { + disable_irq(as3722_rtc->alarm_irq); + as3722_rtc->irq_enable = false; + } + return 0; +} + +static int as3722_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev); + struct as3722 *as3722 = as3722_rtc->as3722; + u8 as_time_array[6]; + int ret; + + ret = as3722_block_read(as3722, AS3722_RTC_ALARM_SECOND_REG, 6, + as_time_array); + if (ret < 0) { + dev_err(dev, "RTC_ALARM_SECOND block read failed %d\n", ret); + return ret; + } + + as3722_reg_to_time(as_time_array, &alrm->time); + return 0; +} + +static int as3722_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev); + struct as3722 *as3722 = as3722_rtc->as3722; + u8 as_time_array[6]; + int ret; + + if (alrm->time.tm_year < (AS3722_RTC_START_YEAR - 1900)) + return -EINVAL; + + ret = as3722_rtc_alarm_irq_enable(dev, 0); + if (ret < 0) { + dev_err(dev, "Disable RTC alarm failed\n"); + return ret; + } + + as3722_time_to_reg(as_time_array, &alrm->time); + ret = as3722_block_write(as3722, AS3722_RTC_ALARM_SECOND_REG, 6, + as_time_array); + if (ret < 0) { + dev_err(dev, "RTC_ALARM_SECOND block write failed %d\n", ret); + return ret; + } + + if (alrm->enabled) + ret = as3722_rtc_alarm_irq_enable(dev, alrm->enabled); + return ret; +} + +static irqreturn_t as3722_alarm_irq(int irq, void *data) +{ + struct as3722_rtc *as3722_rtc = data; + + rtc_update_irq(as3722_rtc->rtc, 1, RTC_IRQF | RTC_AF); + return IRQ_HANDLED; +} + +static const struct rtc_class_ops as3722_rtc_ops = { + .read_time = as3722_rtc_read_time, + .set_time = as3722_rtc_set_time, + .read_alarm = as3722_rtc_read_alarm, + .set_alarm = as3722_rtc_set_alarm, + .alarm_irq_enable = as3722_rtc_alarm_irq_enable, +}; + +static int as3722_rtc_probe(struct platform_device *pdev) +{ + struct as3722 *as3722 = dev_get_drvdata(pdev->dev.parent); + struct as3722_rtc *as3722_rtc; + int ret; + + as3722_rtc = devm_kzalloc(&pdev->dev, sizeof(*as3722_rtc), GFP_KERNEL); + if (!as3722_rtc) + return -ENOMEM; + + as3722_rtc->as3722 = as3722; + as3722_rtc->dev = &pdev->dev; + platform_set_drvdata(pdev, as3722_rtc); + + /* Enable the RTC to make sure it is running. */ + ret = as3722_update_bits(as3722, AS3722_RTC_CONTROL_REG, + AS3722_RTC_ON | AS3722_RTC_ALARM_WAKEUP_EN, + AS3722_RTC_ON | AS3722_RTC_ALARM_WAKEUP_EN); + if (ret < 0) { + dev_err(&pdev->dev, "RTC_CONTROL reg write failed: %d\n", ret); + return ret; + } + + device_init_wakeup(&pdev->dev, 1); + + as3722_rtc->rtc = rtc_device_register("as3722", &pdev->dev, + &as3722_rtc_ops, THIS_MODULE); + if (IS_ERR(as3722_rtc->rtc)) { + ret = PTR_ERR(as3722_rtc->rtc); + dev_err(&pdev->dev, "RTC register failed: %d\n", ret); + return ret; + } + + as3722_rtc->alarm_irq = platform_get_irq(pdev, 0); + dev_info(&pdev->dev, "RTC interrupt %d\n", as3722_rtc->alarm_irq); + + ret = request_threaded_irq(as3722_rtc->alarm_irq, NULL, + as3722_alarm_irq, IRQF_ONESHOT | IRQF_EARLY_RESUME, + "rtc-alarm", as3722_rtc); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to request alarm IRQ %d: %d\n", + as3722_rtc->alarm_irq, ret); + goto scrub; + } + disable_irq(as3722_rtc->alarm_irq); + return 0; +scrub: + rtc_device_unregister(as3722_rtc->rtc); + return ret; +} + +static int as3722_rtc_remove(struct platform_device *pdev) +{ + struct as3722_rtc *as3722_rtc = platform_get_drvdata(pdev); + + free_irq(as3722_rtc->alarm_irq, as3722_rtc); + rtc_device_unregister(as3722_rtc->rtc); + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int as3722_rtc_suspend(struct device *dev) +{ + struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + enable_irq_wake(as3722_rtc->alarm_irq); + + return 0; +} + +static int as3722_rtc_resume(struct device *dev) +{ + struct as3722_rtc *as3722_rtc = dev_get_drvdata(dev); + + if (device_may_wakeup(dev)) + disable_irq_wake(as3722_rtc->alarm_irq); + return 0; +} +#endif + +static const struct dev_pm_ops as3722_rtc_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(as3722_rtc_suspend, as3722_rtc_resume) +}; + +static struct platform_driver as3722_rtc_driver = { + .probe = as3722_rtc_probe, + .remove = as3722_rtc_remove, + .driver = { + .name = "as3722-rtc", + .pm = &as3722_rtc_pm_ops, + }, +}; +module_platform_driver(as3722_rtc_driver); + +MODULE_DESCRIPTION("RTC driver for AS3722 PMICs"); +MODULE_ALIAS("platform:as3722-rtc"); +MODULE_AUTHOR("Florian Lobmaier <florian.lobmaier@ams.com>"); +MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>"); +MODULE_LICENSE("GPL"); |