/* * RTC driver for Maxim MAX8998 * * Copyright (C) 2010 Samsung Electronics Co.Ltd * Author: Minkyu Kang * Author: Joonyoung Shim * * 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 #include #include #include #include #include #include #include #include #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; bool lp3974_bug_workaround; }; 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]; int ret; max8998_tm_to_data(tm, data); ret = max8998_bulk_write(info->rtc, MAX8998_RTC_SEC, 8, data); if (info->lp3974_bug_workaround) msleep(2000); return ret; } 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) { int ret = max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, 0); if (info->lp3974_bug_workaround) msleep(2000); return ret; } static int max8998_rtc_start_alarm(struct max8998_rtc_info *info) { int ret; u8 alarm0_conf = 0x77; /* LP3974 with delay bug chips has rtc alarm bugs with "MONTH" field */ if (info->lp3974_bug_workaround) alarm0_conf = 0x57; ret = max8998_write_reg(info->rtc, MAX8998_ALARM0_CONF, alarm0_conf); if (info->lp3974_bug_workaround) msleep(2000); return ret; } 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 (info->lp3974_bug_workaround) msleep(2000); if (alrm->enabled) ret = max8998_rtc_start_alarm(info); return ret; } 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_platform_data *pdata = dev_get_platdata(max8998->dev); 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); dev_info(&pdev->dev, "RTC CHIP NAME: %s\n", pdev->id_entry->name); if (pdata->rtc_delay) { info->lp3974_bug_workaround = true; dev_warn(&pdev->dev, "LP3974 with RTC REGERR option." " RTC updates will be extremely slow.\n"); } 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 const struct platform_device_id max8998_rtc_id[] = { { "max8998-rtc", TYPE_MAX8998 }, { "lp3974-rtc", TYPE_LP3974 }, { } }; static struct platform_driver max8998_rtc_driver = { .driver = { .name = "max8998-rtc", .owner = THIS_MODULE, }, .probe = max8998_rtc_probe, .remove = __devexit_p(max8998_rtc_remove), .id_table = max8998_rtc_id, }; 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 "); MODULE_AUTHOR("Joonyoung Shim "); MODULE_DESCRIPTION("Maxim MAX8998 RTC driver"); MODULE_LICENSE("GPL");