/* * 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 #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; int irq; }; 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) { alrm->enabled = 0; } else { ret = max8925_reg_read(info->rtc, MAX8925_ALARM0_CNTL); if (ret < 0) goto out; if (!ret) alrm->enabled = 0; else alrm->enabled = 1; } 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; return 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; if (alrm->enabled) /* only enable alarm on year/month/day/hour/min/sec */ ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x77); else ret = max8925_reg_write(info->rtc, MAX8925_ALARM0_CNTL, 0x0); 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 max8925_rtc_probe(struct platform_device *pdev) { struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent); struct max8925_rtc_info *info; int ret; info = devm_kzalloc(&pdev->dev, sizeof(struct max8925_rtc_info), GFP_KERNEL); if (!info) return -ENOMEM; info->chip = chip; info->rtc = chip->rtc; info->dev = &pdev->dev; info->irq = platform_get_irq(pdev, 0); ret = devm_request_threaded_irq(&pdev->dev, info->irq, NULL, rtc_update_handler, IRQF_ONESHOT, "rtc-alarm0", info); if (ret < 0) { dev_err(chip->dev, "Failed to request IRQ: #%d: %d\n", info->irq, ret); return ret; } dev_set_drvdata(&pdev->dev, info); /* XXX - isn't this redundant? */ platform_set_drvdata(pdev, info); device_init_wakeup(&pdev->dev, 1); info->rtc_dev = devm_rtc_device_register(&pdev->dev, "max8925-rtc", &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); return ret; } return 0; } static int max8925_rtc_remove(struct platform_device *pdev) { return 0; } #ifdef CONFIG_PM_SLEEP static int max8925_rtc_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent); if (device_may_wakeup(dev)) chip->wakeup_flag |= 1 << MAX8925_IRQ_RTC_ALARM0; return 0; } static int max8925_rtc_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent); if (device_may_wakeup(dev)) chip->wakeup_flag &= ~(1 << MAX8925_IRQ_RTC_ALARM0); return 0; } #endif static SIMPLE_DEV_PM_OPS(max8925_rtc_pm_ops, max8925_rtc_suspend, max8925_rtc_resume); static struct platform_driver max8925_rtc_driver = { .driver = { .name = "max8925-rtc", .owner = THIS_MODULE, .pm = &max8925_rtc_pm_ops, }, .probe = max8925_rtc_probe, .remove = max8925_rtc_remove, }; module_platform_driver(max8925_rtc_driver); MODULE_DESCRIPTION("Maxim MAX8925 RTC driver"); MODULE_AUTHOR("Haojian Zhuang "); MODULE_LICENSE("GPL");