--- a/drivers/rtc/Kconfig +++ b/drivers/rtc/Kconfig @@ -625,6 +625,15 @@ config RTC_DRV_NUC900 If you say yes here you get support for the RTC subsystem of the NUC910/NUC920 used in embedded systems. +config RTC_DRV_RTC7301 + tristate "Epson RTC-7301 SF/DG" + help + If you say Y here you will get support for the + Epson RTC-7301 SF/DG RTC chips. + + This driver can also be built as a module. If so, the module + will be called rtc-7301. + comment "on-CPU RTC drivers" config RTC_DRV_DAVINCI --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -76,6 +76,7 @@ obj-$(CONFIG_RTC_DRV_RP5C01) += rtc-rp5c obj-$(CONFIG_RTC_DRV_RS5C313) += rtc-rs5c313.o obj-$(CONFIG_RTC_DRV_RS5C348) += rtc-rs5c348.o obj-$(CONFIG_RTC_DRV_RS5C372) += rtc-rs5c372.o +obj-$(CONFIG_RTC_DRV_RTC7301) += rtc-rtc7301.o obj-$(CONFIG_RTC_DRV_RX8025) += rtc-rx8025.o obj-$(CONFIG_RTC_DRV_RX8581) += rtc-rx8581.o obj-$(CONFIG_RTC_DRV_S35390A) += rtc-s35390a.o --- /dev/null +++ b/drivers/rtc/rtc-rtc7301.c @@ -0,0 +1,219 @@ +/* + * Driver for Epson RTC-7301SF/DG + * + * Copyright (C) 2009 Jose Vasconcellos + * + * 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 <linux/module.h> +#include <linux/rtc.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/delay.h> +#include <linux/bcd.h> + +#define RTC_NAME "rtc7301" +#define RTC_VERSION "0.1" + +/* Epson RTC-7301 register addresses */ +#define RTC7301_SEC 0x00 +#define RTC7301_SEC10 0x01 +#define RTC7301_MIN 0x02 +#define RTC7301_MIN10 0x03 +#define RTC7301_HOUR 0x04 +#define RTC7301_HOUR10 0x05 +#define RTC7301_WEEKDAY 0x06 +#define RTC7301_DAY 0x07 +#define RTC7301_DAY10 0x08 +#define RTC7301_MON 0x09 +#define RTC7301_MON10 0x0A +#define RTC7301_YEAR 0x0B +#define RTC7301_YEAR10 0x0C +#define RTC7301_YEAR100 0x0D +#define RTC7301_YEAR1000 0x0E +#define RTC7301_CTRLREG 0x0F + +static uint8_t __iomem *rtc7301_base; + +#define read_reg(offset) (readb(rtc7301_base + offset) & 0xf) +#define write_reg(offset, data) writeb(data, rtc7301_base + (offset)) + +#define rtc7301_isbusy() (read_reg(RTC7301_CTRLREG) & 1) + +static void rtc7301_init_settings(void) +{ + int i; + + write_reg(RTC7301_CTRLREG, 2); + write_reg(RTC7301_YEAR1000, 2); + udelay(122); + + /* bank 1 */ + write_reg(RTC7301_CTRLREG, 6); + for (i=0; i<15; i++) + write_reg(i, 0); + + /* bank 2 */ + write_reg(RTC7301_CTRLREG, 14); + for (i=0; i<15; i++) + write_reg(i, 0); + write_reg(RTC7301_CTRLREG, 0); +} + +static int rtc7301_get_datetime(struct device *dev, struct rtc_time *dt) +{ + int cnt; + uint8_t buf[16]; + + cnt = 0; + while (rtc7301_isbusy()) { + udelay(244); + if (cnt++ > 100) { + dev_err(dev, "%s: timeout error %x\n", __func__, rtc7301_base[RTC7301_CTRLREG]); + return -EIO; + } + } + + for (cnt=0; cnt<16; cnt++) + buf[cnt] = read_reg(cnt); + + if (buf[RTC7301_SEC10] & 8) { + dev_err(dev, "%s: RTC not set\n", __func__); + return -EINVAL; + } + + memset(dt, 0, sizeof(*dt)); + + dt->tm_sec = buf[RTC7301_SEC] + buf[RTC7301_SEC10]*10; + dt->tm_min = buf[RTC7301_MIN] + buf[RTC7301_MIN10]*10; + dt->tm_hour = buf[RTC7301_HOUR] + buf[RTC7301_HOUR10]*10; + + dt->tm_mday = buf[RTC7301_DAY] + buf[RTC7301_DAY10]*10; + dt->tm_mon = buf[RTC7301_MON] + buf[RTC7301_MON10]*10 - 1; + dt->tm_year = buf[RTC7301_YEAR] + buf[RTC7301_YEAR10]*10 + + buf[RTC7301_YEAR100]*100 + + ((buf[RTC7301_YEAR1000] & 3)*1000) - 1900; + + /* the rtc device may contain illegal values on power up + * according to the data sheet. make sure they are valid. + */ + + return rtc_valid_tm(dt); +} + +static int rtc7301_set_datetime(struct device *dev, struct rtc_time *dt) +{ + int data; + + data = dt->tm_year + 1900; + if (data >= 2100 || data < 1900) + return -EINVAL; + + write_reg(RTC7301_CTRLREG, 2); + udelay(122); + + data = bin2bcd(dt->tm_sec); + write_reg(RTC7301_SEC, data); + write_reg(RTC7301_SEC10, (data >> 4)); + + data = bin2bcd(dt->tm_min); + write_reg(RTC7301_MIN, data ); + write_reg(RTC7301_MIN10, (data >> 4)); + + data = bin2bcd(dt->tm_hour); + write_reg(RTC7301_HOUR, data); + write_reg(RTC7301_HOUR10, (data >> 4)); + + data = bin2bcd(dt->tm_mday); + write_reg(RTC7301_DAY, data); + write_reg(RTC7301_DAY10, (data>> 4)); + + data = bin2bcd(dt->tm_mon + 1); + write_reg(RTC7301_MON, data); + write_reg(RTC7301_MON10, (data >> 4)); + + data = bin2bcd(dt->tm_year % 100); + write_reg(RTC7301_YEAR, data); + write_reg(RTC7301_YEAR10, (data >> 4)); + data = bin2bcd((1900 + dt->tm_year) / 100); + write_reg(RTC7301_YEAR100, data); + + data = bin2bcd(dt->tm_wday); + write_reg(RTC7301_WEEKDAY, data); + + write_reg(RTC7301_CTRLREG, 0); + + return 0; +} + +static const struct rtc_class_ops rtc7301_rtc_ops = { + .read_time = rtc7301_get_datetime, + .set_time = rtc7301_set_datetime, +}; + +static int __devinit rtc7301_probe(struct platform_device *pdev) +{ + struct rtc_device *rtc; + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENOENT; + + rtc7301_base = ioremap_nocache(res->start, 0x1000 /*res->end - res->start + 1*/); + if (!rtc7301_base) + return -EINVAL; + + rtc = rtc_device_register(RTC_NAME, &pdev->dev, + &rtc7301_rtc_ops, THIS_MODULE); + if (IS_ERR(rtc)) { + iounmap(rtc7301_base); + return PTR_ERR(rtc); + } + + platform_set_drvdata(pdev, rtc); + + rtc7301_init_settings(); + return 0; +} + +static int __devexit rtc7301_remove(struct platform_device *pdev) +{ + struct rtc_device *rtc = platform_get_drvdata(pdev); + + if (rtc) + rtc_device_unregister(rtc); + if (rtc7301_base) + iounmap(rtc7301_base); + return 0; +} + +static struct platform_driver rtc7301_driver = { + .driver = { + .name = RTC_NAME, + .owner = THIS_MODULE, + }, + .probe = rtc7301_probe, + .remove = __devexit_p(rtc7301_remove), +}; + +static __init int rtc7301_init(void) +{ + return platform_driver_register(&rtc7301_driver); +} +module_init(rtc7301_init); + +static __exit void rtc7301_exit(void) +{ + platform_driver_unregister(&rtc7301_driver); +} +module_exit(rtc7301_exit); + +MODULE_DESCRIPTION("Epson 7301 RTC driver"); +MODULE_AUTHOR("Jose Vasconcellos <jvasco@verizon.net>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:" RTC_NAME); +MODULE_VERSION(RTC_VERSION);