u-boot/drivers/rtc/rv3029.c
Heiko Schocher 71d19f30d6 rtc, rv3029: add trickle charger support.
Signed-off-by: Heiko Schocher <hs@denx.de>
Acked-by: Detlev Zundel <dzu@denx.de>
2011-04-26 00:24:40 +02:00

211 lines
6 KiB
C

/*
* (C) Copyright 2010
* Heiko Schocher, DENX Software Engineering, hs@denx.de
*
* 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
*/
#include <common.h>
#include <command.h>
#include <i2c.h>
#include <rtc.h>
#define RTC_RV3029_CTRL1 0x00
#define RTC_RV3029_CTRL1_EERE (1 << 3)
#define RTC_RV3029_CTRL_STATUS 0x03
#define RTC_RV3029_CTRLS_EEBUSY (1 << 7)
#define RTC_RV3029_CTRL_RESET 0x04
#define RTC_RV3029_CTRL_SYS_R (1 << 4)
#define RTC_RV3029_CLOCK_PAGE 0x08
#define RTC_RV3029_PAGE_LEN 7
#define RV3029C2_W_SECONDS 0x00
#define RV3029C2_W_MINUTES 0x01
#define RV3029C2_W_HOURS 0x02
#define RV3029C2_W_DATE 0x03
#define RV3029C2_W_DAYS 0x04
#define RV3029C2_W_MONTHS 0x05
#define RV3029C2_W_YEARS 0x06
#define RV3029C2_REG_HR_12_24 (1 << 6) /* 24h/12h mode */
#define RV3029C2_REG_HR_PM (1 << 5) /* PM/AM bit in 12h mode */
#define RTC_RV3029_EEPROM_CTRL 0x30
#define RTC_RV3029_TRICKLE_1K (1 << 4)
#define RTC_RV3029_TRICKLE_5K (1 << 5)
#define RTC_RV3029_TRICKLE_20K (1 << 6)
#define RTC_RV3029_TRICKLE_80K (1 << 7)
int rtc_get( struct rtc_time *tmp )
{
int ret;
unsigned char buf[RTC_RV3029_PAGE_LEN];
ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CLOCK_PAGE, 1, buf, \
RTC_RV3029_PAGE_LEN);
if (ret) {
printf("%s: error reading RTC: %x\n", __func__, ret);
return -1;
}
tmp->tm_sec = bcd2bin( buf[RV3029C2_W_SECONDS] & 0x7f);
tmp->tm_min = bcd2bin( buf[RV3029C2_W_MINUTES] & 0x7f);
if (buf[RV3029C2_W_HOURS] & RV3029C2_REG_HR_12_24) {
/* 12h format */
tmp->tm_hour = bcd2bin(buf[RV3029C2_W_HOURS] & 0x1f);
if (buf[RV3029C2_W_HOURS] & RV3029C2_REG_HR_PM)
/* PM flag set */
tmp->tm_hour += 12;
} else
tmp->tm_hour = bcd2bin(buf[RV3029C2_W_HOURS] & 0x3f);
tmp->tm_mday = bcd2bin( buf[RV3029C2_W_DATE] & 0x3F );
tmp->tm_mon = bcd2bin( buf[RV3029C2_W_MONTHS] & 0x1F );
tmp->tm_wday = bcd2bin( buf[RV3029C2_W_DAYS] & 0x07 );
/* RTC supports only years > 1999 */
tmp->tm_year = bcd2bin( buf[RV3029C2_W_YEARS]) + 2000;
tmp->tm_yday = 0;
tmp->tm_isdst = 0;
#ifdef RTC_DEBUG
printf( "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 );
#endif
return 0;
}
int rtc_set( struct rtc_time *tmp )
{
int ret;
unsigned char buf[RTC_RV3029_PAGE_LEN];
#ifdef RTC_DEBUG
printf( "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);
#endif
if (tmp->tm_year < 2000) {
printf("RTC: year %d < 2000 not possible\n", tmp->tm_year);
return -1;
}
buf[RV3029C2_W_SECONDS] = bin2bcd(tmp->tm_sec);
buf[RV3029C2_W_MINUTES] = bin2bcd(tmp->tm_min);
buf[RV3029C2_W_HOURS] = bin2bcd(tmp->tm_hour);
/* set 24h format */
buf[RV3029C2_W_HOURS] &= ~RV3029C2_REG_HR_12_24;
buf[RV3029C2_W_DATE] = bin2bcd(tmp->tm_mday);
buf[RV3029C2_W_DAYS] = bin2bcd(tmp->tm_wday);
buf[RV3029C2_W_MONTHS] = bin2bcd(tmp->tm_mon);
tmp->tm_year -= 2000;
buf[RV3029C2_W_YEARS] = bin2bcd(tmp->tm_year);
ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CLOCK_PAGE, 1,
buf, RTC_RV3029_PAGE_LEN);
/* give the RTC some time to update */
udelay(1000);
return 0;
}
/* sets EERE-Bit (automatic EEPROM refresh) */
static void set_eere_bit(int state)
{
int ret;
unsigned char reg_ctrl1;
ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL1, 1,
&reg_ctrl1, 1);
if (state)
reg_ctrl1 |= RTC_RV3029_CTRL1_EERE;
else
reg_ctrl1 &= (~RTC_RV3029_CTRL1_EERE);
ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL1, 1,
&reg_ctrl1, 1);
}
/* waits until EEPROM page is no longer busy (times out after 10ms*loops) */
static int wait_eebusy(int loops)
{
int i, ret;
unsigned char ctrl_status;
for (i = 0; i < loops; i++) {
ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_STATUS,
1, &ctrl_status, 1);
if ((ctrl_status & RTC_RV3029_CTRLS_EEBUSY) == 0)
break;
udelay(10000);
}
return i;
}
void rtc_reset (void)
{
int ret;
unsigned char buf[RTC_RV3029_PAGE_LEN];
buf[0] = RTC_RV3029_CTRL_SYS_R;
ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_CTRL_RESET, 1,
buf, 1);
#if defined(CONFIG_SYS_RV3029_TCR)
/*
* because EEPROM_CTRL register is in EEPROM page it is necessary to
* disable automatic EEPROM refresh and check if EEPROM is busy
* before EEPORM_CTRL register may be accessed
*/
set_eere_bit(0);
wait_eebusy(100);
/* read current trickle charger setting */
ret = i2c_read(CONFIG_SYS_I2C_RTC_ADDR, RTC_RV3029_EEPROM_CTRL,
1, buf, 1);
/* enable automatic EEPROM refresh again */
set_eere_bit(1);
/*
* to minimize EEPROM access write trickle charger setting only if it
* differs from current value
*/
if ((buf[0] & 0xF0) != CONFIG_SYS_RV3029_TCR) {
buf[0] = (buf[0] & 0x0F) | CONFIG_SYS_RV3029_TCR;
/*
* write trickle charger setting (disable autom. EEPROM
* refresh and wait until EEPROM is idle)
*/
set_eere_bit(0);
wait_eebusy(100);
ret = i2c_write(CONFIG_SYS_I2C_RTC_ADDR,
RTC_RV3029_EEPROM_CTRL, 1, buf, 1);
/*
* it is necessary to wait 10ms before EEBUSY-Bit may be read
* (this is not documented in the data sheet yet, but the
* manufacturer recommends it)
*/
udelay(10000);
/* wait until EEPROM write access is finished */
wait_eebusy(100);
set_eere_bit(1);
}
#endif
}