Lockpick_RCM/bdk/rtc/max77620-rtc.c

148 lines
4.0 KiB
C

/*
* PMIC Real Time Clock driver for Nintendo Switch's MAX77620-RTC
*
* Copyright (c) 2018-2019 CTCaer
* Copyright (c) 2019 shchmue
*
* 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 <rtc/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;
u8 hour = i2c_recv_byte(I2C_5, MAX77620_RTC_I2C_ADDR, MAX77620_RTC_HOUR_REG);
time->hour = hour & 0x1F;
if (!(val & MAX77620_RTC_24H) && (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->day = 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);
}
void max77620_rtc_epoch_to_date(u32 epoch, rtc_time_t *time)
{
u32 tmp, edays, year, month, day;
// Set time.
time->sec = epoch % 60;
epoch /= 60;
time->min = epoch % 60;
epoch /= 60;
time->hour = epoch % 24;
epoch /= 24;
// Calculate base date values.
tmp = (u32)(((u64)4 * epoch + 102032) / 146097 + 15);
tmp = (u32)((u64)epoch + 2442113 + tmp - (tmp >> 2));
year = (20 * tmp - 2442) / 7305;
edays = tmp - 365 * year - (year >> 2);
month = edays * 1000 / 30601;
day = edays - month * 30 - month * 601 / 1000;
// Month/Year offset.
if(month < 14)
{
year -= 4716;
month--;
}
else
{
year -= 4715;
month -= 13;
}
// Set date.
time->year = year;
time->month = month;
time->day = day;
// Set weekday.
time->weekday = 0; //! TODO.
}
u32 max77620_rtc_date_to_epoch(const rtc_time_t *time)
{
u32 year, month, epoch;
//Year
year = time->year;
//Month of year
month = time->month;
// Month/Year offset.
if(month < 3)
{
month += 12;
year--;
}
epoch = (365 * year) + (year >> 2) - (year / 100) + (year / 400); // Years to days.
epoch += (30 * month) + (3 * (month + 1) / 5) + time->day; // Months to days.
epoch -= 719561; // Epoch time is 1/1/1970.
epoch *= 86400; // Days to seconds.
epoch += (3600 * time->hour) + (60 * time->min) + time->sec; // Add hours, minutes and seconds.
return epoch;
}