hekate/bdk/rtc/max77620-rtc.c
CTCaer 185526d134 Introducing Bootloader Development Kit (BDK)
BDK will allow developers to use the full collection of drivers,
with limited editing, if any, for making payloads for Nintendo Switch.

Using a single source for everything will also help decoupling
Switch specific code and easily port it to other Tegra X1/X1+ platforms.
And maybe even to lower targets.

Everything is now centrilized into bdk folder.
Every module or project can utilize it by simply including it.

This is just the start and it will continue to improve.
2020-06-14 15:25:21 +03:00

147 lines
4 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 "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;
}