From a39069f6ce6500a5ca39e534108247f25169d8e0 Mon Sep 17 00:00:00 2001 From: Haojian Zhuang Date: Mon, 25 Jan 2010 06:30:29 -0500 Subject: rtc: Enable rtc in max8925 MAX8925 is a PMIC that contains RTC component. Signed-off-by: Haojian Zhuang Signed-off-by: Samuel Ortiz --- drivers/rtc/rtc-max8925.c | 314 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 314 insertions(+) create mode 100644 drivers/rtc/rtc-max8925.c (limited to 'drivers/rtc/rtc-max8925.c') diff --git a/drivers/rtc/rtc-max8925.c b/drivers/rtc/rtc-max8925.c new file mode 100644 index 000000000000..acdbb1760187 --- /dev/null +++ b/drivers/rtc/rtc-max8925.c @@ -0,0 +1,314 @@ +/* + * RTC driver for Maxim MAX8925 + * + * Copyright (C) 2009-2010 Marvell International Ltd. + * Haojian Zhuang + * + * 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 +#include +#include +#include +#include + +enum { + RTC_SEC = 0, + RTC_MIN, + RTC_HOUR, + RTC_WEEKDAY, + RTC_DATE, + RTC_MONTH, + RTC_YEAR1, + RTC_YEAR2, +}; + +#define MAX8925_RTC_SEC 0x00 +#define MAX8925_RTC_MIN 0x01 +#define MAX8925_RTC_HOUR 0x02 +#define MAX8925_RTC_WEEKDAY 0x03 +#define MAX8925_RTC_DATE 0x04 +#define MAX8925_RTC_MONTH 0x05 +#define MAX8925_RTC_YEAR1 0x06 +#define MAX8925_RTC_YEAR2 0x07 +#define MAX8925_ALARM0_SEC 0x08 +#define MAX8925_ALARM0_MIN 0x09 +#define MAX8925_ALARM0_HOUR 0x0a +#define MAX8925_ALARM0_WEEKDAY 0x0b +#define MAX8925_ALARM0_DATE 0x0c +#define MAX8925_ALARM0_MON 0x0d +#define MAX8925_ALARM0_YEAR1 0x0e +#define MAX8925_ALARM0_YEAR2 0x0f +#define MAX8925_ALARM1_SEC 0x10 +#define MAX8925_ALARM1_MIN 0x11 +#define MAX8925_ALARM1_HOUR 0x12 +#define MAX8925_ALARM1_WEEKDAY 0x13 +#define MAX8925_ALARM1_DATE 0x14 +#define MAX8925_ALARM1_MON 0x15 +#define MAX8925_ALARM1_YEAR1 0x16 +#define MAX8925_ALARM1_YEAR2 0x17 +#define MAX8925_RTC_CNTL 0x1b +#define MAX8925_RTC_STATUS 0x20 + +#define TIME_NUM 8 +#define ALARM_1SEC (1 << 7) +#define HOUR_12 (1 << 7) +#define HOUR_AM_PM (1 << 5) +#define ALARM0_IRQ (1 << 3) +#define ALARM1_IRQ (1 << 2) +#define ALARM0_STATUS (1 << 2) +#define ALARM1_STATUS (1 << 1) + + +struct max8925_rtc_info { + struct rtc_device *rtc_dev; + struct max8925_chip *chip; + struct i2c_client *rtc; + struct device *dev; +}; + +static irqreturn_t rtc_update_handler(int irq, void *data) +{ + struct max8925_rtc_info *info = (struct max8925_rtc_info *)data; + + /* disable ALARM0 except for 1SEC alarm */ + max8925_set_bits(info->rtc, MAX8925_ALARM0_CNTL, 0x7f, 0); + rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF); + return IRQ_HANDLED; +} + +static int tm_calc(struct rtc_time *tm, unsigned char *buf, int len) +{ + if (len < TIME_NUM) + return -EINVAL; + tm->tm_year = (buf[RTC_YEAR2] >> 4) * 1000 + + (buf[RTC_YEAR2] & 0xf) * 100 + + (buf[RTC_YEAR1] >> 4) * 10 + + (buf[RTC_YEAR1] & 0xf); + tm->tm_year -= 1900; + tm->tm_mon = ((buf[RTC_MONTH] >> 4) & 0x01) * 10 + + (buf[RTC_MONTH] & 0x0f); + tm->tm_mday = ((buf[RTC_DATE] >> 4) & 0x03) * 10 + + (buf[RTC_DATE] & 0x0f); + tm->tm_wday = buf[RTC_WEEKDAY] & 0x07; + if (buf[RTC_HOUR] & HOUR_12) { + tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x1) * 10 + + (buf[RTC_HOUR] & 0x0f); + if (buf[RTC_HOUR] & HOUR_AM_PM) + tm->tm_hour += 12; + } else + tm->tm_hour = ((buf[RTC_HOUR] >> 4) & 0x03) * 10 + + (buf[RTC_HOUR] & 0x0f); + tm->tm_min = ((buf[RTC_MIN] >> 4) & 0x7) * 10 + + (buf[RTC_MIN] & 0x0f); + tm->tm_sec = ((buf[RTC_SEC] >> 4) & 0x7) * 10 + + (buf[RTC_SEC] & 0x0f); + return 0; +} + +static int data_calc(unsigned char *buf, struct rtc_time *tm, int len) +{ + unsigned char high, low; + + if (len < TIME_NUM) + return -EINVAL; + + high = (tm->tm_year + 1900) / 1000; + low = (tm->tm_year + 1900) / 100; + low = low - high * 10; + buf[RTC_YEAR2] = (high << 4) + low; + high = (tm->tm_year + 1900) / 10; + low = tm->tm_year + 1900; + low = low - high * 10; + high = high - (high / 10) * 10; + buf[RTC_YEAR1] = (high << 4) + low; + high = tm->tm_mon / 10; + low = tm->tm_mon; + low = low - high * 10; + buf[RTC_MONTH] = (high << 4) + low; + high = tm->tm_mday / 10; + low = tm->tm_mday; + low = low - high * 10; + buf[RTC_DATE] = (high << 4) + low; + buf[RTC_WEEKDAY] = tm->tm_wday; + high = tm->tm_hour / 10; + low = tm->tm_hour; + low = low - high * 10; + buf[RTC_HOUR] = (high << 4) + low; + high = tm->tm_min / 10; + low = tm->tm_min; + low = low - high * 10; + buf[RTC_MIN] = (high << 4) + low; + high = tm->tm_sec / 10; + low = tm->tm_sec; + low = low - high * 10; + buf[RTC_SEC] = (high << 4) + low; + return 0; +} + +static int max8925_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct max8925_rtc_info *info = dev_get_drvdata(dev); + unsigned char buf[TIME_NUM]; + int ret; + + ret = max8925_bulk_read(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf); + if (ret < 0) + goto out; + ret = tm_calc(tm, buf, TIME_NUM); +out: + return ret; +} + +static int max8925_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct max8925_rtc_info *info = dev_get_drvdata(dev); + unsigned char buf[TIME_NUM]; + int ret; + + ret = data_calc(buf, tm, TIME_NUM); + if (ret < 0) + goto out; + ret = max8925_bulk_write(info->rtc, MAX8925_RTC_SEC, TIME_NUM, buf); +out: + return ret; +} + +static int max8925_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct max8925_rtc_info *info = dev_get_drvdata(dev); + unsigned char buf[TIME_NUM]; + int ret; + + ret = max8925_bulk_read(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf); + if (ret < 0) + goto out; + ret = tm_calc(&alrm->time, buf, TIME_NUM); + if (ret < 0) + goto out; + ret = max8925_reg_read(info->rtc, MAX8925_RTC_IRQ_MASK); + if (ret < 0) + goto out; + if ((ret & ALARM0_IRQ) == 0) + alrm->enabled = 1; + else + alrm->enabled = 0; + ret = max8925_reg_read(info->rtc, MAX8925_RTC_STATUS); + if (ret < 0) + goto out; + if (ret & ALARM0_STATUS) + alrm->pending = 1; + else + alrm->pending = 0; +out: + return ret; +} + +static int max8925_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct max8925_rtc_info *info = dev_get_drvdata(dev); + unsigned char buf[TIME_NUM]; + int ret; + + ret = data_calc(buf, &alrm->time, TIME_NUM); + if (ret < 0) + goto out; + ret = max8925_bulk_write(info->rtc, MAX8925_ALARM0_SEC, TIME_NUM, buf); + if (ret < 0) + goto out; + /* only enable alarm on year/month/day/hour/min/sec */ + ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x77); + if (ret < 0) + goto out; +out: + return ret; +} + +static const struct rtc_class_ops max8925_rtc_ops = { + .read_time = max8925_rtc_read_time, + .set_time = max8925_rtc_set_time, + .read_alarm = max8925_rtc_read_alarm, + .set_alarm = max8925_rtc_set_alarm, +}; + +static int __devinit max8925_rtc_probe(struct platform_device *pdev) +{ + struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent); + struct max8925_rtc_info *info; + int irq, ret; + + info = kzalloc(sizeof(struct max8925_rtc_info), GFP_KERNEL); + if (!info) + return -ENOMEM; + info->chip = chip; + info->rtc = chip->rtc; + info->dev = &pdev->dev; + irq = chip->irq_base + MAX8925_IRQ_RTC_ALARM0; + + ret = request_threaded_irq(irq, NULL, rtc_update_handler, + IRQF_ONESHOT, "rtc-alarm0", info); + if (ret < 0) { + dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n", + irq, ret); + goto out_irq; + } + + info->rtc_dev = rtc_device_register("max8925-rtc", &pdev->dev, + &max8925_rtc_ops, THIS_MODULE); + ret = PTR_ERR(info->rtc_dev); + if (IS_ERR(info->rtc_dev)) { + dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret); + goto out_rtc; + } + + dev_set_drvdata(&pdev->dev, info); + platform_set_drvdata(pdev, info); + + return 0; +out_rtc: + free_irq(chip->irq_base + MAX8925_IRQ_RTC_ALARM0, info); +out_irq: + kfree(info); + return ret; +} + +static int __devexit max8925_rtc_remove(struct platform_device *pdev) +{ + struct max8925_rtc_info *info = platform_get_drvdata(pdev); + + if (info) { + free_irq(info->chip->irq_base + MAX8925_IRQ_RTC_ALARM0, info); + rtc_device_unregister(info->rtc_dev); + kfree(info); + } + return 0; +} + +static struct platform_driver max8925_rtc_driver = { + .driver = { + .name = "max8925-rtc", + .owner = THIS_MODULE, + }, + .probe = max8925_rtc_probe, + .remove = __devexit_p(max8925_rtc_remove), +}; + +static int __init max8925_rtc_init(void) +{ + return platform_driver_register(&max8925_rtc_driver); +} +module_init(max8925_rtc_init); + +static void __exit max8925_rtc_exit(void) +{ + platform_driver_unregister(&max8925_rtc_driver); +} +module_exit(max8925_rtc_exit); + +MODULE_DESCRIPTION("Maxim MAX8925 RTC driver"); +MODULE_AUTHOR("Haojian Zhuang "); +MODULE_LICENSE("GPL"); + -- cgit v1.2.3-59-g8ed1b