From 48802d37079bfc3e705cd43af78b7b2186a02046 Mon Sep 17 00:00:00 2001
From: Raghavendra Ganiga ravi23ganiga@gmail.com Date: Thu, 17 Apr 2014 23:14:22 +0530 Subject: [PATCH] rtc: add support maxim dallas rtc ds1347
This is a patch to add support for maxim dallas rtc ds1347
Signed-off-by: Raghavendra Chandra Ganiga ravi23ganiga@gmail.com --- drivers/rtc/Makefile | 1 + drivers/rtc/ds1347.c | 180 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 181 insertions(+) create mode 100644 drivers/rtc/ds1347.c
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile index 003d322..d26d4e1 100644 --- a/drivers/rtc/Makefile +++ b/drivers/rtc/Makefile @@ -17,6 +17,7 @@ obj-$(CONFIG_RTC_DS1306) += ds1306.o obj-$(CONFIG_RTC_DS1307) += ds1307.o obj-$(CONFIG_RTC_DS1338) += ds1307.o obj-$(CONFIG_RTC_DS1337) += ds1337.o +obj-$(CONFIG_RTC_DS1347) += ds1347.o obj-$(CONFIG_RTC_DS1374) += ds1374.o obj-$(CONFIG_RTC_DS1388) += ds1337.o obj-$(CONFIG_RTC_DS1556) += ds1556.o diff --git a/drivers/rtc/ds1347.c b/drivers/rtc/ds1347.c new file mode 100644 index 0000000..b452c36 --- /dev/null +++ b/drivers/rtc/ds1347.c @@ -0,0 +1,180 @@ +/* + * Dallas Maxim RTC DS1347 Driver + * + * Copyright (C) 2014 Raghavendra Chandra Ganiga ravi23ganiga@gmail.com + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <rtc.h> +#include <spi.h> + +#if defined(CONFIG_CMD_DATE) + +/* +* DS1347 Registers +*/ +#define RTC_SECONDS_REG 0x01 +#define RTC_MINUTES_REG 0x03 +#define RTC_HOURS_REG 0x05 +#define RTC_DATE_REG 0x07 +#define RTC_MONTH_REG 0x09 +#define RTC_DAY_REG 0x0B +#define RTC_YEAR_REG 0x0D +#define RTC_CONTROL_REG 0x0F +#define RTC_CENTURY_REG 0x13 +#define RTC_ALARM_CONFIG_REG 0x15 +#define RTC_STATUS_REG 0x17 +#define RTC_ALARM_SEC_REG 0x19 +#define RTC_ALARM_MIN_REG 0x1B +#define RTC_ALARM_HOUR_REG 0x1D +#define RTC_ALARM_DATE_REG 0x1F +#define RTC_ALARM_MONTH_REG 0x21 +#define RTC_ALARM_DAY_REG 0x23 +#define RTC_ALARM_YEAR_REG 0x25 +#define RTC_BURST_REG 0x3F + +static struct spi_slave *slave; + +static unsigned char rtc_read(unsigned char address); +static int rtc_write(unsigned char address, unsigned char value); + +int rtc_get(struct rtc_time *tm) +{ + int ret; + unsigned char data, century; + if (!slave) { + slave = spi_setup_slave(CONFIG_DS1347_BUS, + CONFIG_DS1347_CS, 1000000, + SPI_MODE_3); + if (!slave) + return -1; + } + + ret = spi_claim_bus(slave); + if (ret) + return -1; + + data = rtc_read(RTC_SECONDS_REG); + tm->tm_sec = bcd2bin(data); + + data = rtc_read(RTC_MINUTES_REG); + tm->tm_min = bcd2bin(data); + + data = rtc_read(RTC_HOURS_REG); + tm->tm_hour = bcd2bin(data); + + data = rtc_read(RTC_DATE_REG); + tm->tm_mday = bcd2bin(data); + + data = rtc_read(RTC_MONTH_REG); + tm->tm_mon = bcd2bin(data); + + /* use the century register support in rtc */ + century = rtc_read(RTC_CENTURY_REG); + data = rtc_read(RTC_YEAR_REG); + tm->tm_year = bcd2bin(data) + (bcd2bin(century) * 100); + + data = rtc_read(RTC_DAY_REG); + tm->tm_wday = bcd2bin(data) - 1; + + tm->tm_yday = 0; + tm->tm_isdst = 0; + + spi_release_bus(slave); + + return 0; +} + +int rtc_set(struct rtc_time *tm) +{ + int ret; + unsigned char data; + + if (!slave) { + slave = spi_setup_slave(CONFIG_DS1347_BUS, + CONFIG_DS1347_CS, 1000000, + SPI_MODE_3); + + if (!slave) + return -1; + } + + ret = spi_claim_bus(slave); + if (ret) + return -1; + + rtc_write(RTC_SECONDS_REG, bin2bcd(tm->tm_sec)); + + rtc_write(RTC_MINUTES_REG, bin2bcd(tm->tm_min)); + + rtc_write(RTC_HOURS_REG, bin2bcd(tm->tm_hour)); + + rtc_write(RTC_DATE_REG, bin2bcd(tm->tm_mday)); + + rtc_write(RTC_MONTH_REG, bin2bcd(tm->tm_mon)); + + /* use the century register support in rtc */ + data = tm->tm_year / 100; + rtc_write(RTC_CENTURY_REG, bin2bcd(data)); + + data = tm->tm_year % 100; + rtc_write(RTC_YEAR_REG, bin2bcd(data)); + + rtc_write(RTC_DAY_REG, bin2bcd(tm->tm_wday + 1)); + + spi_release_bus(slave); + + return 0; +} + +void rtc_reset(void) +{ + int ret; + + if (!slave) { + slave = spi_setup_slave(CONFIG_DS1347_BUS, + CONFIG_DS1347_CS, 1000000, + SPI_MODE_3); + + if (!slave) + return; + } + + ret = spi_claim_bus(slave); + if (ret) + return; + + /* Disable Write Protection */ + ret = rtc_write(RTC_CONTROL_REG, 0x00); + + /* Disable RTC Alarm - no alarm support */ + ret = rtc_write(RTC_ALARM_CONFIG_REG, 0x00); + + /* Enable Oscillator and No Glitch Filter */ + ret = rtc_write(RTC_STATUS_REG, 0x00); + + spi_release_bus(slave); +} +/* +* Helper Functions +*/ +static unsigned char rtc_read(unsigned char address) +{ + address |= 0x80; + + return spi_w8r8(slave, address); +} + +static int rtc_write(unsigned char address, unsigned char value) +{ + unsigned char dout[2]; + + dout[0] = address; + dout[1] = value; + + return spi_xfer(slave, 16, dout, NULL, SPI_XFER_BEGIN | SPI_XFER_END); +} + +#endif /* CONFIG_CMD_DATE */