/* * Copyright 2010 Freescale Semiconductor, Inc. * * Author: Priyanka Jain <Priyanka.Jain@freescale.com> * * See file CREDITS for list of people who contributed to this * project. * * 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. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ /* * This file provides Date & Time support (no alarms) for PT7C4338 chip. * * This file is based on drivers/rtc/ds1337.c * * PT7C4338 chip is manufactured by Pericom Technology Inc. * It is a serial real-time clock which provides * 1)Low-power clock/calendar. * 2)Programmable square-wave output. * It has 56 bytes of nonvolatile RAM. */ #include <common.h> #include <command.h> #include <rtc.h> #include <i2c.h> /* RTC register addresses */ #define RTC_SEC_REG_ADDR 0x0 #define RTC_MIN_REG_ADDR 0x1 #define RTC_HR_REG_ADDR 0x2 #define RTC_DAY_REG_ADDR 0x3 #define RTC_DATE_REG_ADDR 0x4 #define RTC_MON_REG_ADDR 0x5 #define RTC_YR_REG_ADDR 0x6 #define RTC_CTL_STAT_REG_ADDR 0x7 /* RTC second register address bit */ #define RTC_SEC_BIT_CH 0x80 /* Clock Halt (in Register 0) */ /* RTC control and status register bits */ #define RTC_CTL_STAT_BIT_RS0 0x1 /* Rate select 0 */ #define RTC_CTL_STAT_BIT_RS1 0x2 /* Rate select 1 */ #define RTC_CTL_STAT_BIT_SQWE 0x10 /* Square Wave Enable */ #define RTC_CTL_STAT_BIT_OSF 0x20 /* Oscillator Stop Flag */ #define RTC_CTL_STAT_BIT_OUT 0x80 /* Output Level Control */ /* RTC reset value */ #define RTC_PT7C4338_RESET_VAL \ (RTC_CTL_STAT_BIT_RS0 | RTC_CTL_STAT_BIT_RS1 | RTC_CTL_STAT_BIT_OUT) /****** Helper functions ****************************************/ static u8 rtc_read(u8 reg) { return i2c_reg_read(CONFIG_SYS_I2C_RTC_ADDR, reg); } static void rtc_write(u8 reg, u8 val) { i2c_reg_write(CONFIG_SYS_I2C_RTC_ADDR, reg, val); } /****************************************************************/ /* Get the current time from the RTC */ int rtc_get(struct rtc_time *tmp) { int ret = 0; u8 sec, min, hour, mday, wday, mon, year, ctl_stat; ctl_stat = rtc_read(RTC_CTL_STAT_REG_ADDR); sec = rtc_read(RTC_SEC_REG_ADDR); min = rtc_read(RTC_MIN_REG_ADDR); hour = rtc_read(RTC_HR_REG_ADDR); wday = rtc_read(RTC_DAY_REG_ADDR); mday = rtc_read(RTC_DATE_REG_ADDR); mon = rtc_read(RTC_MON_REG_ADDR); year = rtc_read(RTC_YR_REG_ADDR); debug("Get RTC year: %02x mon: %02x mday: %02x wday: %02x " "hr: %02x min: %02x sec: %02x control_status: %02x\n", year, mon, mday, wday, hour, min, sec, ctl_stat); if (ctl_stat & RTC_CTL_STAT_BIT_OSF) { printf("### Warning: RTC oscillator has stopped\n"); /* clear the OSF flag */ rtc_write(RTC_CTL_STAT_REG_ADDR, rtc_read(RTC_CTL_STAT_REG_ADDR)\ & ~RTC_CTL_STAT_BIT_OSF); ret = -1; } tmp->tm_sec = bcd2bin(sec & 0x7F); tmp->tm_min = bcd2bin(min & 0x7F); tmp->tm_hour = bcd2bin(hour & 0x3F); tmp->tm_mday = bcd2bin(mday & 0x3F); tmp->tm_mon = bcd2bin(mon & 0x1F); tmp->tm_year = bcd2bin(year) + 2000; tmp->tm_wday = bcd2bin((wday - 1) & 0x07); tmp->tm_yday = 0; tmp->tm_isdst = 0; debug("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, tmp->tm_hour, tmp->tm_min, tmp->tm_sec); return ret; } /* Set the RTC */ int rtc_set(struct rtc_time *tmp) { debug("Set DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n", tmp->tm_year, tmp->tm_mon, tmp->tm_mday, tmp->tm_wday, tmp->tm_hour, tmp->tm_min, tmp->tm_sec); rtc_write(RTC_YR_REG_ADDR, bin2bcd(tmp->tm_year % 100)); rtc_write(RTC_MON_REG_ADDR, bin2bcd(tmp->tm_mon)); rtc_write(RTC_DAY_REG_ADDR, bin2bcd(tmp->tm_wday + 1)); rtc_write(RTC_DATE_REG_ADDR, bin2bcd(tmp->tm_mday)); rtc_write(RTC_HR_REG_ADDR, bin2bcd(tmp->tm_hour)); rtc_write(RTC_MIN_REG_ADDR, bin2bcd(tmp->tm_min)); rtc_write(RTC_SEC_REG_ADDR, bin2bcd(tmp->tm_sec)); return 0; } /* Reset the RTC */ void rtc_reset(void) { rtc_write(RTC_SEC_REG_ADDR, 0x00); /* clearing Clock Halt */ rtc_write(RTC_CTL_STAT_REG_ADDR, RTC_PT7C4338_RESET_VAL); }