i2c_pad_ctrl.c

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/* SPDX-License-Identifier: GPL-2.0-only */
 
#include <amdblocks/acpimmio.h>
#include <amdblocks/i2c.h>
#include <console/console.h>
#include <types.h>
#include "i2c_pad_def.h"
 
void fch_i2c_pad_init(unsigned int bus,
                      enum i2c_speed speed,
                      const struct i2c_pad_control *ctrl)
{
        uint32_t pad_ctrl;
 
        pad_ctrl = misc_read32(MISC_I2C_PAD_CTRL(bus));
 
        pad_ctrl &= ~I2C_PAD_CTRL_NG_MASK;
        pad_ctrl |= I2C_PAD_CTRL_NG_NORMAL;
 
        switch (ctrl->rx_level) {
        case I2C_PAD_RX_NO_CHANGE:
                break;
        case I2C_PAD_RX_OFF:
                pad_ctrl &= ~I2C_PAD_CTRL_RX_SEL_MASK;
                pad_ctrl |= I2C_PAD_CTRL_RX_SEL_OFF;
                break;
        case I2C_PAD_RX_3_3V:
                pad_ctrl &= ~I2C_PAD_CTRL_RX_SEL_MASK;
                pad_ctrl |= I2C_PAD_CTRL_RX_SEL_3_3V;
                break;
        case I2C_PAD_RX_1_8V:
                pad_ctrl &= ~I2C_PAD_CTRL_RX_SEL_MASK;
                pad_ctrl |= I2C_PAD_CTRL_RX_SEL_1_8V;
                break;
        default:
                printk(BIOS_WARNING, "Invalid I2C pad RX level for bus %u\n", bus);
                break;
        }
 
        pad_ctrl &= ~I2C_PAD_CTRL_FALLSLEW_MASK;
        pad_ctrl |= speed == I2C_SPEED_STANDARD ?
                I2C_PAD_CTRL_FALLSLEW_STD : I2C_PAD_CTRL_FALLSLEW_LOW;
        pad_ctrl |= I2C_PAD_CTRL_FALLSLEW_EN;
        misc_write32(MISC_I2C_PAD_CTRL(bus), pad_ctrl);
}