/*
 * Copyright (c) 2017-2019, ARM Limited and Contributors. All rights reserved.
 * Copyright (c) 2018, Icenowy Zheng <icenowy@aosc.io>
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */

#include <errno.h>

#include <common/debug.h>
#include <drivers/allwinner/axp.h>
#include <drivers/allwinner/sunxi_rsb.h>

#include <sunxi_def.h>
#include <sunxi_mmap.h>
#include <sunxi_private.h>

#define AXP805_HW_ADDR	0x745
#define AXP805_RT_ADDR	0x3a

static enum pmic_type {
	UNKNOWN,
	AXP805,
} pmic;

int axp_read(uint8_t reg)
{
	return rsb_read(AXP805_RT_ADDR, reg);
}

int axp_write(uint8_t reg, uint8_t val)
{
	return rsb_write(AXP805_RT_ADDR, reg, val);
}

static int rsb_init(void)
{
	int ret;

	ret = rsb_init_controller();
	if (ret)
		return ret;

	/* Switch to the recommended 3 MHz bus clock. */
	ret = rsb_set_bus_speed(SUNXI_OSC24M_CLK_IN_HZ, 3000000);
	if (ret)
		return ret;

	/* Initiate an I2C transaction to switch the PMIC to RSB mode. */
	ret = rsb_set_device_mode(AXP20X_MODE_RSB << 16 | AXP20X_MODE_REG << 8);
	if (ret)
		return ret;

	/* Associate the 8-bit runtime address with the 12-bit bus address. */
	ret = rsb_assign_runtime_address(AXP805_HW_ADDR, AXP805_RT_ADDR);
	if (ret)
		return ret;

	return axp_check_id();
}

int sunxi_pmic_setup(uint16_t socid, const void *fdt)
{
	int ret;

	INFO("PMIC: Probing AXP805 on RSB\n");

	ret = sunxi_init_platform_r_twi(socid, true);
	if (ret)
		return ret;

	ret = rsb_init();
	if (ret)
		return ret;

	/* Switch the AXP805 to master/single-PMIC mode. */
	ret = axp_write(0xff, 0x0);
	if (ret)
		return ret;

	pmic = AXP805;
	axp_setup_regulators(fdt);

	/* Switch the PMIC back to I2C mode. */
	ret = axp_write(AXP20X_MODE_REG, AXP20X_MODE_I2C);
	if (ret)
		return ret;

	return 0;
}

void sunxi_power_down(void)
{
	switch (pmic) {
	case AXP805:
		/* (Re-)init RSB in case the rich OS has disabled it. */
		sunxi_init_platform_r_twi(SUNXI_SOC_H6, true);
		rsb_init();
		axp_power_off();
		break;
	default:
		break;
	}
}