| /* |
| * 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> |
| #include <linux/delay.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; |
| 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 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 = devm_kzalloc(&pdev->dev, 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; |
| |
| platform_set_drvdata(pdev, info); |
| |
| info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8998-rtc", |
| &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; |
| } |
| |
| ret = devm_request_threaded_irq(&pdev->dev, 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: |
| platform_set_drvdata(pdev, NULL); |
| return ret; |
| } |
| |
| static int max8998_rtc_remove(struct platform_device *pdev) |
| { |
| 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 = max8998_rtc_remove, |
| .id_table = max8998_rtc_id, |
| }; |
| |
| module_platform_driver(max8998_rtc_driver); |
| |
| 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"); |