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/*
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 * Fan driver for Nintendo Switch
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 *
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 * Copyright (c) 2018-2024 CTCaer
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 *
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 * This program is free software; you can redistribute it and/or modify it
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 * under the terms and conditions of the GNU General Public License,
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 * version 2, as published by the Free Software Foundation.
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 *
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 * This program is distributed in the hope it will be useful, but WITHOUT
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
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 * more details.
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 *
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 * You should have received a copy of the GNU General Public License
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 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
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 */
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#include <thermal/fan.h>
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#include <power/regulator_5v.h>
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#include <soc/bpmp.h>
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#include <soc/clock.h>
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#include <soc/fuse.h>
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#include <soc/gpio.h>
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#include <soc/hw_init.h>
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#include <soc/pinmux.h>
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#include <soc/timer.h>
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#include <soc/t210.h>
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void fan_set_duty(u32 duty)
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{
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	static bool fan_init = false;
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	static u16  curr_duty = -1;
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	if (duty > 236)
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		duty = 236;
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	if (curr_duty == duty)
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		return;
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	curr_duty = duty;
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	if (!fan_init)
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	{
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		// Fan tachometer.
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		u32 pull_resistor = hw_get_chip_id() == GP_HIDREV_MAJOR_T210 ? PINMUX_PULL_UP : 0;
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		PINMUX_AUX(PINMUX_AUX_CAM1_PWDN) = PINMUX_TRISTATE | PINMUX_INPUT_ENABLE | pull_resistor | 1;
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		gpio_direction_input(GPIO_PORT_S, GPIO_PIN_7);
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		// Enable PWM if disabled.
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		if (fuse_read_hw_type() == FUSE_NX_HW_TYPE_AULA)
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			clock_enable_pwm();
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		PWM(PWM_CONTROLLER_PWM_CSR_1) = PWM_CSR_EN | (0x100 << 16); // Max PWM to disable fan.
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		PINMUX_AUX(PINMUX_AUX_LCD_GPIO2) = 1; // Set source to PWM1.
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		gpio_config(GPIO_PORT_V, GPIO_PIN_4, GPIO_MODE_SPIO); // Fan power mode.
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		fan_init = true;
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	}
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	// Inverted polarity.
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	u32 inv_duty = 236 - duty;
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	// If disabled send a 0 duty.
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	if (inv_duty == 236)
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	{
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		PWM(PWM_CONTROLLER_PWM_CSR_1) = PWM_CSR_EN | (0x100 << 16); // Bit 24 is absolute 0%.
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		regulator_5v_disable(REGULATOR_5V_FAN);
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		// Disable fan.
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		PINMUX_AUX(PINMUX_AUX_LCD_GPIO2) = PINMUX_INPUT_ENABLE | PINMUX_PARKED    |
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										   PINMUX_TRISTATE     | PINMUX_PULL_DOWN; // Set source to PWM1.
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	}
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	else // Set PWM duty.
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	{
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		// Fan power supply.
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		regulator_5v_enable(REGULATOR_5V_FAN);
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		PWM(PWM_CONTROLLER_PWM_CSR_1) = PWM_CSR_EN | (inv_duty << 16);
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		// Enable fan.
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		PINMUX_AUX(PINMUX_AUX_LCD_GPIO2) = 1; // Set source to PWM1.
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	}
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}
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void fan_get_speed(u32 *duty, u32 *rpm)
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{
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	if (rpm)
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	{
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		u32  irq_count = 0;
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		bool should_read = true;
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		// Poll irqs for 2 seconds. (5 seconds for accurate count).
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		int  timer = get_tmr_us() + 2000000;
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		while ((timer - get_tmr_us()) > 0)
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		{
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			bool irq_val = gpio_read(GPIO_PORT_S, GPIO_PIN_7);
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			if (irq_val && should_read)
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			{
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				irq_count++;
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				should_read = false;
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			}
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			else if (!irq_val)
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				should_read = true;
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		}
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		// Halve the irq count.
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		irq_count /= 2;
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		// Calculate rpm based on triggered interrupts.
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		*rpm = irq_count * (60 / 2);
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	}
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	if (duty)
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		*duty = 236 - ((PWM(PWM_CONTROLLER_PWM_CSR_1) >> 16) & 0xFF);
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}
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void fan_set_from_temp(u32 temp)
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{
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	if (temp >= 52)
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		fan_set_duty(102);
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	else if (temp >= 47)
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		fan_set_duty(76);
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	else if (temp >= 42)
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		fan_set_duty(51);
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	else if (temp <= 39)
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		fan_set_duty(0);
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}
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