TegraExplorer/source/rtc/max77620-rtc.c

78 lines
2.6 KiB
C

/*
* PMIC Real Time Clock driver for Nintendo Switch's MAX77620-RTC
*
* Copyright (c) 2018 CTCaer
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
*/
#include "max77620-rtc.h"
#include "../soc/i2c.h"
#include "../utils/util.h"
void max77620_rtc_get_time(rtc_time_t *time)
{
u8 val = 0;
// Update RTC regs from RTC clock.
i2c_send_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_UPDATE0_REG, MAX77620_RTC_READ_UPDATE);
// Get control reg config.
val = i2c_recv_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_CONTROL_REG);
// TODO: Check for binary format also?
// Get time.
time->sec = i2c_recv_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_SEC_REG) & 0x7F;
time->min = i2c_recv_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_MIN_REG) & 0x7F;
time->hour = i2c_recv_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_HOUR_REG) & 0x1F;
if (!(val & MAX77620_RTC_24H) && time->hour & MAX77620_RTC_HOUR_PM_MASK)
time->hour = (time->hour & 0xF) + 12;
// Get day of week. 1: Monday to 7: Sunday.
time->weekday = 0;
val = i2c_recv_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_WEEKDAY_REG);
for (int i = 0; i < 8; i++)
{
time->weekday++;
if (val & 1)
break;
val >>= 1;
}
// Get date.
time->date = i2c_recv_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_DATE_REG) & 0x1f;
time->month = (i2c_recv_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_MONTH_REG) & 0xF) - 1;
time->year = (i2c_recv_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_YEAR_REG) & 0x7F) + 2000;
}
void max77620_rtc_stop_alarm()
{
u8 val = 0;
// Update RTC regs from RTC clock.
i2c_send_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_UPDATE0_REG, MAX77620_RTC_READ_UPDATE);
// Stop alarm for both ALARM1 and ALARM2. Horizon uses ALARM2.
for (int i = 0; i < (MAX77620_RTC_NR_TIME_REGS * 2); i++)
{
val = i2c_recv_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_ALARM1_SEC_REG + i);
val &= ~MAX77620_RTC_ALARM_EN_MASK;
i2c_send_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_ALARM1_SEC_REG + i, val);
}
// Update RTC clock from RTC regs.
i2c_send_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_UPDATE0_REG, MAX77620_RTC_WRITE_UPDATE);
}