u-boot/drivers/rtc/pcf2127.c
Meng Yi 8f3a8428c9 rtc: Add RTC chip pcf2127 support
This driver compatible with pcf2127 and pcf2129

Signed-off-by: Meng Yi <meng.yi@nxp.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2016-12-02 21:03:31 -07:00

107 lines
2.6 KiB
C

/*
* Copyright (C) 2016 by NXP Semiconductors Inc.
* Date & Time support for PCF2127 RTC
*/
/* #define DEBUG */
#include <common.h>
#include <command.h>
#include <dm.h>
#include <i2c.h>
#include <rtc.h>
#define PCF2127_REG_CTRL1 (0x00)
#define PCF2127_REG_CTRL2 (0x01)
#define PCF2127_REG_CTRL3 (0x02)
#define PCF2127_REG_SC (0x03) /* datetime */
#define PCF2127_REG_MN (0x04)
#define PCF2127_REG_HR (0x05)
#define PCF2127_REG_DM (0x06)
#define PCF2127_REG_DW (0x07)
#define PCF2127_REG_MO (0x08)
#define PCF2127_REG_YR (0x09)
static int pcf2127_rtc_set(struct udevice *dev, const struct rtc_time *tm)
{
uchar buf[8];
int i = 0;
/* start register address */
buf[i++] = PCF2127_REG_SC;
/* hours, minutes and seconds */
buf[i++] = bin2bcd(tm->tm_sec);
buf[i++] = bin2bcd(tm->tm_min);
buf[i++] = bin2bcd(tm->tm_hour);
buf[i++] = bin2bcd(tm->tm_mday);
buf[i++] = tm->tm_wday & 0x07;
/* month, 1 - 12 */
buf[i++] = bin2bcd(tm->tm_mon + 1);
/* year */
buf[i++] = bin2bcd(tm->tm_year % 100);
/* write register's data */
if (dm_i2c_write(dev, PCF2127_REG_CTRL1, buf, sizeof(buf)) < 0)
return -1;
return 0;
}
static int pcf2127_rtc_get(struct udevice *dev, struct rtc_time *tm)
{
int rel = 0;
uchar buf[10] = { PCF2127_REG_CTRL1 };
if (dm_i2c_write(dev, PCF2127_REG_CTRL1, buf, 1) < 0)
return -1;
if (dm_i2c_read(dev, PCF2127_REG_CTRL1, buf, sizeof(buf)) < 0)
return -1;
if (buf[PCF2127_REG_CTRL3] & 0x04)
puts("### Warning: RTC Low Voltage - date/time not reliable\n");
tm->tm_sec = bcd2bin(buf[PCF2127_REG_SC] & 0x7F);
tm->tm_min = bcd2bin(buf[PCF2127_REG_MN] & 0x7F);
tm->tm_hour = bcd2bin(buf[PCF2127_REG_HR] & 0x3F);
tm->tm_mday = bcd2bin(buf[PCF2127_REG_DM] & 0x3F);
tm->tm_mon = bcd2bin(buf[PCF2127_REG_MO] & 0x1F) - 1;
tm->tm_year = bcd2bin(buf[PCF2127_REG_YR]) + 1900;
if (tm->tm_year < 1970)
tm->tm_year += 100; /* assume we are in 1970...2069 */
tm->tm_wday = buf[PCF2127_REG_DW] & 0x07;
tm->tm_yday = 0;
tm->tm_isdst = 0;
debug("Get DATE: %4d-%02d-%02d (wday=%d) TIME: %2d:%02d:%02d\n",
tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_wday,
tm->tm_hour, tm->tm_min, tm->tm_sec);
return rel;
}
static int pcf2127_rtc_reset(struct udevice *dev)
{
/*Doing nothing here*/
return 0;
}
static const struct rtc_ops pcf2127_rtc_ops = {
.get = pcf2127_rtc_get,
.set = pcf2127_rtc_set,
.reset = pcf2127_rtc_reset,
};
static const struct udevice_id pcf2127_rtc_ids[] = {
{ .compatible = "pcf2127-rtc" },
{ }
};
U_BOOT_DRIVER(rtc_pcf2127) = {
.name = "rtc-pcf2127",
.id = UCLASS_RTC,
.of_match = pcf2127_rtc_ids,
.ops = &pcf2127_rtc_ops,
};