xref: /rk3399_rockchip-uboot/drivers/i2c/muxes/max96745.c (revision a7a8e68169f79f6d0f9ec66f00b487f452fdfa54)

// SPDX-License-Identifier: GPL-2.0+
/*
 * (C) Copyright 2022 Rockchip Electronics Co., Ltd
 */

#include <asm-generic/gpio.h>
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <i2c.h>
#include <max96745.h>

struct max96745_priv {
	struct udevice *dev;
	struct gpio_desc enable_gpio;
	struct gpio_desc pwdnb_gpio;
	bool idle_disc;
};

static int max96745_select(struct udevice *mux, struct udevice *bus,
			   uint channel)
{
	struct max96745_priv *priv = dev_get_priv(mux);

	if (!priv->idle_disc)
		return 0;

	if (channel == 1)
		dm_i2c_reg_clrset(mux, 0x0086, DIS_REM_CC,
				  FIELD_PREP(DIS_REM_CC, 0));
	else
		dm_i2c_reg_clrset(mux, 0x0076, DIS_REM_CC,
				  FIELD_PREP(DIS_REM_CC, 0));

	return 0;
}

static int max96745_deselect(struct udevice *mux, struct udevice *bus,
			     uint channel)
{
	struct max96745_priv *priv = dev_get_priv(mux);

	if (!priv->idle_disc)
		return 0;

	if (channel == 1)
		dm_i2c_reg_clrset(mux, 0x0086, DIS_REM_CC,
				  FIELD_PREP(DIS_REM_CC, 1));
	else
		dm_i2c_reg_clrset(mux, 0x0076, DIS_REM_CC,
				  FIELD_PREP(DIS_REM_CC, 1));

	return 0;
}

static const struct i2c_mux_ops max96745_ops = {
	.select = max96745_select,
	.deselect = max96745_deselect,
};

static int max96745_power_on(struct max96745_priv *priv)
{
	int ret;

	if (dm_gpio_is_valid(&priv->enable_gpio)) {
		dm_gpio_set_value(&priv->enable_gpio, 1);
		mdelay(200);
	}

	if (dm_gpio_is_valid(&priv->pwdnb_gpio)) {
		dm_gpio_set_value(&priv->pwdnb_gpio, 0);
		mdelay(30);
	}

	/* Set for I2C Fast-mode speed */
	ret = dm_i2c_reg_write(priv->dev, 0x0070, 0x16);
	if (ret < 0)
		return ret;

	if (priv->idle_disc) {
		ret = dm_i2c_reg_clrset(priv->dev, 0x0076, DIS_REM_CC,
					FIELD_PREP(DIS_REM_CC, 1));
		if (ret < 0)
			return ret;

		ret = dm_i2c_reg_clrset(priv->dev, 0x0086, DIS_REM_CC,
					FIELD_PREP(DIS_REM_CC, 1));
		if (ret < 0)
			return ret;
	}

	return 0;
}

static int max96745_probe(struct udevice *dev)
{
	struct max96745_priv *priv = dev_get_priv(dev);
	int ret;

	ret = i2c_set_chip_offset_len(dev, 2);
	if (ret)
		return ret;

	priv->dev = dev;
	priv->idle_disc = dev_read_bool(dev, "i2c-mux-idle-disconnect");

	ret = gpio_request_by_name(dev, "enable-gpios", 0,
				   &priv->enable_gpio, GPIOD_IS_OUT);
	if (ret && ret != -ENOENT) {
		dev_err(dev, "%s: failed to get enable GPIO: %d\n", __func__, ret);
		return ret;
	}

	ret = gpio_request_by_name(dev, "pwdnb-gpios", 0,
				   &priv->pwdnb_gpio, GPIOD_IS_OUT);
	if (ret && ret != -ENOENT) {
		dev_err(dev, "%s: failed to get pwdnb GPIO: %d\n", __func__, ret);
		return ret;
	}

	max96745_power_on(priv);

	return 0;
}

static const struct udevice_id max96745_of_match[] = {
	{ .compatible = "maxim,max96745" },
	{}
};

U_BOOT_DRIVER(max96745) = {
	.name = "max96745",
	.id = UCLASS_I2C_MUX,
	.of_match = max96745_of_match,
	.bind = dm_scan_fdt_dev,
	.probe = max96745_probe,
	.ops = &max96745_ops,
	.priv_auto_alloc_size = sizeof(struct max96745_priv),
};