zephyr/drivers/i2c/i2c_npcx_port.c

176 lines
4.9 KiB
C

/*
* Copyright (c) 2020 Nuvoton Technology Corporation.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT nuvoton_npcx_i2c_port
/**
* @file
* @brief Nuvoton NPCX smb/i2c port driver
*
* This file contains the driver of SMBus/I2C buses (ports) which provides
* pin-muxing for each i2c io-pads. In order to support "SMBus Multi-Bus"
* feature, please refer the diagram below, the driver also provides connection
* between Zephyr i2c api functions and i2c controller driver which provides
* full support for SMBus/I2C transactions.
*
* Port SEL
* |
* |\|
* SCL_N Port 0----| \ +--------------+
* SDA_N Port 0----| |----| SMB/I2C |
* | |----| Controller N |
* SCL_N Port 1----| | +--------------+
* SDA_N Port 1----| /
* |/
*
*/
#include <assert.h>
#include <zephyr/drivers/clock_control.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/pinctrl.h>
#include <zephyr/dt-bindings/i2c/i2c.h>
#include <soc.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(i2c_npcx_port, LOG_LEVEL_ERR);
#include "i2c_npcx_controller.h"
#include "i2c-priv.h"
/* Device config */
struct i2c_npcx_port_config {
uint32_t bitrate;
uint8_t port;
const struct device *i2c_ctrl;
/* pinmux configuration */
const struct pinctrl_dev_config *pcfg;
};
/* I2C api functions */
static int i2c_npcx_port_configure(const struct device *dev,
uint32_t dev_config)
{
const struct i2c_npcx_port_config *const config = dev->config;
if (config->i2c_ctrl == NULL) {
LOG_ERR("Cannot find i2c controller on port%02x!",
config->port);
return -EIO;
}
if (!(dev_config & I2C_MODE_CONTROLLER)) {
return -ENOTSUP;
}
if (dev_config & I2C_ADDR_10_BITS) {
return -ENOTSUP;
}
/* Configure i2c controller */
return npcx_i2c_ctrl_configure(config->i2c_ctrl, dev_config);
}
static int i2c_npcx_port_get_config(const struct device *dev, uint32_t *dev_config)
{
const struct i2c_npcx_port_config *const config = dev->config;
uint32_t speed;
int ret;
if (config->i2c_ctrl == NULL) {
LOG_ERR("Cannot find i2c controller on port%02x!", config->port);
return -EIO;
}
ret = npcx_i2c_ctrl_get_speed(config->i2c_ctrl, &speed);
if (!ret) {
*dev_config = (I2C_MODE_CONTROLLER | speed);
}
return ret;
}
static int i2c_npcx_port_transfer(const struct device *dev,
struct i2c_msg *msgs, uint8_t num_msgs, uint16_t addr)
{
const struct i2c_npcx_port_config *const config = dev->config;
int ret = 0;
int idx_ctrl = (config->port & 0xF0) >> 4;
int idx_port = (config->port & 0x0F);
if (config->i2c_ctrl == NULL) {
LOG_ERR("Cannot find i2c controller on port%02x!",
config->port);
return -EIO;
}
/* Lock mutex of i2c/smb controller */
npcx_i2c_ctrl_mutex_lock(config->i2c_ctrl);
/* Switch correct port for i2c controller first */
npcx_pinctrl_i2c_port_sel(idx_ctrl, idx_port);
/* Start transaction with i2c controller */
ret = npcx_i2c_ctrl_transfer(config->i2c_ctrl, msgs, num_msgs, addr,
config->port);
/* Unlock mutex of i2c/smb controller */
npcx_i2c_ctrl_mutex_unlock(config->i2c_ctrl);
return ret;
}
/* I2C driver registration */
static int i2c_npcx_port_init(const struct device *dev)
{
const struct i2c_npcx_port_config *const config = dev->config;
uint32_t i2c_config;
int ret;
/* Configure pin-mux for I2C device */
ret = pinctrl_apply_state(config->pcfg, PINCTRL_STATE_DEFAULT);
if (ret < 0) {
LOG_ERR("I2C pinctrl setup failed (%d)", ret);
return ret;
}
/* Setup initial i2c configuration */
i2c_config = (I2C_MODE_CONTROLLER | i2c_map_dt_bitrate(config->bitrate));
ret = i2c_npcx_port_configure(dev, i2c_config);
if (ret != 0) {
return ret;
}
return 0;
}
static const struct i2c_driver_api i2c_port_npcx_driver_api = {
.configure = i2c_npcx_port_configure,
.get_config = i2c_npcx_port_get_config,
.transfer = i2c_npcx_port_transfer,
};
/* I2C port init macro functions */
#define NPCX_I2C_PORT_INIT(inst) \
PINCTRL_DT_INST_DEFINE(inst); \
\
static const struct i2c_npcx_port_config i2c_npcx_port_cfg_##inst = { \
.port = DT_INST_PROP(inst, port), \
.bitrate = DT_INST_PROP(inst, clock_frequency), \
.i2c_ctrl = DEVICE_DT_GET(DT_INST_PHANDLE(inst, controller)), \
.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(inst), \
}; \
\
DEVICE_DT_INST_DEFINE(inst, \
i2c_npcx_port_init, \
NULL, NULL, \
&i2c_npcx_port_cfg_##inst, \
PRE_KERNEL_1, CONFIG_I2C_INIT_PRIORITY, \
&i2c_port_npcx_driver_api);
DT_INST_FOREACH_STATUS_OKAY(NPCX_I2C_PORT_INIT)