diff options
Diffstat (limited to 'drivers/rtc/rtc-max8998.c')
| -rw-r--r-- | drivers/rtc/rtc-max8998.c | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-max8998.c b/drivers/rtc/rtc-max8998.c new file mode 100644 index 000000000000..f22dee35f330 --- /dev/null +++ b/drivers/rtc/rtc-max8998.c @@ -0,0 +1,300 @@ +/* + * RTC driver for Maxim MAX8998 + * + * Copyright (C) 2010 Samsung Electronics Co.Ltd + * Author: Minkyu Kang <mk7.kang@samsung.com> + * Author: Joonyoung Shim <jy0922.shim@samsung.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/module.h> +#include <linux/i2c.h> +#include <linux/slab.h> +#include <linux/bcd.h> +#include <linux/rtc.h> +#include <linux/platform_device.h> +#include <linux/mfd/max8998.h> +#include <linux/mfd/max8998-private.h> + +#define MAX8998_RTC_SEC 0x00 +#define MAX8998_RTC_MIN 0x01 +#define MAX8998_RTC_HOUR 0x02 +#define MAX8998_RTC_WEEKDAY 0x03 +#define MAX8998_RTC_DATE 0x04 +#define MAX8998_RTC_MONTH 0x05 +#define MAX8998_RTC_YEAR1 0x06 +#define MAX8998_RTC_YEAR2 0x07 +#define MAX8998_ALARM0_SEC 0x08 +#define MAX8998_ALARM0_MIN 0x09 +#define MAX8998_ALARM0_HOUR 0x0a +#define MAX8998_ALARM0_WEEKDAY 0x0b +#define MAX8998_ALARM0_DATE 0x0c +#define MAX8998_ALARM0_MONTH 0x0d +#define MAX8998_ALARM0_YEAR1 0x0e +#define MAX8998_ALARM0_YEAR2 0x0f +#define MAX8998_ALARM1_SEC 0x10 +#define MAX8998_ALARM1_MIN 0x11 +#define MAX8998_ALARM1_HOUR 0x12 +#define MAX8998_ALARM1_WEEKDAY 0x13 +#define MAX8998_ALARM1_DATE 0x14 +#define MAX8998_ALARM1_MONTH 0x15 +#define MAX8998_ALARM1_YEAR1 0x16 +#define MAX8998_ALARM1_YEAR2 0x17 +#define MAX8998_ALARM0_CONF 0x18 +#define MAX8998_ALARM1_CONF 0x19 +#define MAX8998_RTC_STATUS 0x1a +#define MAX8998_WTSR_SMPL_CNTL 0x1b +#define MAX8998_TEST 0x1f + +#define HOUR_12 (1 << 7) +#define HOUR_PM (1 << 5) +#define ALARM0_STATUS (1 << 1) +#define ALARM1_STATUS (1 << 2) + +enum { + RTC_SEC = 0, + RTC_MIN, + RTC_HOUR, + RTC_WEEKDAY, + RTC_DATE, + RTC_MONTH, + RTC_YEAR1, + RTC_YEAR2, +}; + +struct max8998_rtc_info { + struct device *dev; + struct max8998_dev *max8998; + struct i2c_client *rtc; + struct rtc_device *rtc_dev; + int irq; +}; + +static void max8998_data_to_tm(u8 *data, struct rtc_time *tm) +{ + tm->tm_sec = bcd2bin(data[RTC_SEC]); + tm->tm_min = bcd2bin(data[RTC_MIN]); + if (data[RTC_HOUR] & HOUR_12) { + tm->tm_hour = bcd2bin(data[RTC_HOUR] & 0x1f); + if (data[RTC_HOUR] & HOUR_PM) + tm->tm_hour += 12; + } else + tm->tm_hour = bcd2bin(data[RTC_HOUR] & 0x3f); + + tm->tm_wday = data[RTC_WEEKDAY] & 0x07; + tm->tm_mday = bcd2bin(data[RTC_DATE]); + tm->tm_mon = bcd2bin(data[RTC_MONTH]); + tm->tm_year = bcd2bin(data[RTC_YEAR1]) + bcd2bin(data[RTC_YEAR2]) * 100; + tm->tm_year -= 1900; +} + +static void max8998_tm_to_data(struct rtc_time *tm, u8 *data) +{ + data[RTC_SEC] = bin2bcd(tm->tm_sec); + data[RTC_MIN] = bin2bcd(tm->tm_min); + data[RTC_HOUR] = bin2bcd(tm->tm_hour); + data[RTC_WEEKDAY] = tm->tm_wday; + data[RTC_DATE] = bin2bcd(tm->tm_mday); + data[RTC_MONTH] = bin2bcd(tm->tm_mon); + data[RTC_YEAR1] = bin2bcd(tm->tm_year % 100); + data[RTC_YEAR2] = bin2bcd((tm->tm_year + 1900) / 100); +} + +static int max8998_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct max8998_rtc_info *info = dev_get_drvdata(dev); + u8 data[8]; + int ret; + + ret = max8998_bulk_read(info->rtc, MAX8998_RTC_SEC, 8, data); + if (ret < 0) + return ret; + + max8998_data_to_tm(data, tm); + + return rtc_valid_tm(tm); +} + +static int max8998_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct max8998_rtc_info *info = dev_get_drvdata(dev); + u8 data[8]; + + max8998_tm_to_data(tm, data); + + return max8998_bulk_write(info->rtc, MAX8998_RTC_SEC, 8, data); +} + +static int max8998_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct max8998_rtc_info *info = dev_get_drvdata(dev); + u8 data[8]; + u8 val; + int ret; + + ret = max8998_bulk_read(info->rtc, MAX8998_ALARM0_SEC, 8, data); + if (ret < 0) + return ret; + + max8998_data_to_tm(data, &alrm->time); + + ret = max8998_read_reg(info->rtc, MAX8998_ALARM0_CONF, &val); + if (ret < 0) + return ret; + + alrm->enabled = !!val; + + ret = max8998_read_reg(info->rtc, MAX8998_RTC_STATUS, &val); + if (ret < 0) + return ret; + + if (val & ALARM0_STATUS) + alrm->pending = 1; + else + alrm->pending = 0; + + return 0; +} + +static int max8998_rtc_stop_alarm(struct max8998_rtc_info *info) +{ + return max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, 0); +} + +static int max8998_rtc_start_alarm(struct max8998_rtc_info *info) +{ + return max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, 0x77); +} + +static int max8998_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct max8998_rtc_info *info = dev_get_drvdata(dev); + u8 data[8]; + int ret; + + max8998_tm_to_data(&alrm->time, data); + + ret = max8998_rtc_stop_alarm(info); + if (ret < 0) + return ret; + + ret = max8998_bulk_write(info->rtc, MAX8998_ALARM0_SEC, 8, data); + if (ret < 0) + return ret; + + if (alrm->enabled) + return max8998_rtc_start_alarm(info); + + return 0; +} + +static int max8998_rtc_alarm_irq_enable(struct device *dev, + unsigned int enabled) +{ + struct max8998_rtc_info *info = dev_get_drvdata(dev); + + if (enabled) + return max8998_rtc_start_alarm(info); + else + return max8998_rtc_stop_alarm(info); +} + +static irqreturn_t max8998_rtc_alarm_irq(int irq, void *data) +{ + struct max8998_rtc_info *info = data; + + rtc_update_irq(info->rtc_dev, 1, RTC_IRQF | RTC_AF); + + return IRQ_HANDLED; +} + +static const struct rtc_class_ops max8998_rtc_ops = { + .read_time = max8998_rtc_read_time, + .set_time = max8998_rtc_set_time, + .read_alarm = max8998_rtc_read_alarm, + .set_alarm = max8998_rtc_set_alarm, + .alarm_irq_enable = max8998_rtc_alarm_irq_enable, +}; + +static int __devinit max8998_rtc_probe(struct platform_device *pdev) +{ + struct max8998_dev *max8998 = dev_get_drvdata(pdev->dev.parent); + struct max8998_rtc_info *info; + int ret; + + info = kzalloc(sizeof(struct max8998_rtc_info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + info->dev = &pdev->dev; + info->max8998 = max8998; + info->rtc = max8998->rtc; + info->irq = max8998->irq_base + MAX8998_IRQ_ALARM0; + + info->rtc_dev = rtc_device_register("max8998-rtc", &pdev->dev, + &max8998_rtc_ops, THIS_MODULE); + + if (IS_ERR(info->rtc_dev)) { + ret = PTR_ERR(info->rtc_dev); + dev_err(&pdev->dev, "Failed to register RTC device: %d\n", ret); + goto out_rtc; + } + + platform_set_drvdata(pdev, info); + + ret = request_threaded_irq(info->irq, NULL, max8998_rtc_alarm_irq, 0, + "rtc-alarm0", info); + if (ret < 0) + dev_err(&pdev->dev, "Failed to request alarm IRQ: %d: %d\n", + info->irq, ret); + + return 0; + +out_rtc: + kfree(info); + return ret; +} + +static int __devexit max8998_rtc_remove(struct platform_device *pdev) +{ + struct max8998_rtc_info *info = platform_get_drvdata(pdev); + + if (info) { + free_irq(info->irq, info); + rtc_device_unregister(info->rtc_dev); + kfree(info); + } + + return 0; +} + +static struct platform_driver max8998_rtc_driver = { + .driver = { + .name = "max8998-rtc", + .owner = THIS_MODULE, + }, + .probe = max8998_rtc_probe, + .remove = __devexit_p(max8998_rtc_remove), +}; + +static int __init max8998_rtc_init(void) +{ + return platform_driver_register(&max8998_rtc_driver); +} +module_init(max8998_rtc_init); + +static void __exit max8998_rtc_exit(void) +{ + platform_driver_unregister(&max8998_rtc_driver); +} +module_exit(max8998_rtc_exit); + +MODULE_AUTHOR("Minkyu Kang <mk7.kang@samsung.com>"); +MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>"); +MODULE_DESCRIPTION("Maxim MAX8998 RTC driver"); +MODULE_LICENSE("GPL"); |