zephyr/drivers/i2c/i2c_renesas_ra_iic.c

557 lines
19 KiB
C

/*
* Copyright (c) 2024 Renesas Electronics Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT renesas_ra_iic
#include <math.h>
#include <zephyr/devicetree.h>
#include <zephyr/drivers/clock_control.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/pinctrl.h>
#include <zephyr/irq.h>
#include <zephyr/sys/util.h>
#include "r_iic_master.h"
#include <errno.h>
#include <soc.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(renesas_ra_iic);
typedef void (*init_func_t)(const struct device *dev);
static const double RA_IIC_MASTER_DIV_TIME_NS = 1000000000;
struct i2c_ra_iic_config {
void (*irq_config_func)(const struct device *dev);
const struct pinctrl_dev_config *pcfg;
uint32_t noise_filter_stage;
double rise_time_s;
double fall_time_s;
uint32_t duty_cycle_percent;
};
struct i2c_ra_iic_data {
iic_master_instance_ctrl_t ctrl;
i2c_master_cfg_t fsp_config;
struct k_mutex bus_mutex;
struct k_sem complete_sem;
i2c_master_event_t event;
iic_master_extended_cfg_t iic_master_ext_cfg;
uint32_t dev_config;
};
/* IIC master clock setting calculation function. */
static void calc_iic_master_clock_setting(const struct device *dev, const uint32_t fsp_i2c_rate,
iic_master_clock_settings_t *clk_cfg);
/* FSP interruption handlers. */
void iic_master_rxi_isr(void);
void iic_master_txi_isr(void);
void iic_master_tei_isr(void);
void iic_master_eri_isr(void);
struct ra_iic_master_bitrate {
uint32_t bitrate;
uint32_t duty;
uint32_t divider;
uint32_t brl;
uint32_t brh;
uint32_t duty_error_percent;
};
static int i2c_ra_iic_configure(const struct device *dev, uint32_t dev_config)
{
struct i2c_ra_iic_data *data = (struct i2c_ra_iic_data *const)dev->data;
if (!(dev_config & I2C_MODE_CONTROLLER)) {
LOG_ERR("Only I2C Master mode supported.");
return -EIO;
}
switch (I2C_SPEED_GET(dev_config)) {
case I2C_SPEED_STANDARD:
data->fsp_config.rate = I2C_MASTER_RATE_STANDARD;
break;
case I2C_SPEED_FAST:
data->fsp_config.rate = I2C_MASTER_RATE_FAST;
break;
case I2C_SPEED_FAST_PLUS:
data->fsp_config.rate = I2C_MASTER_RATE_FASTPLUS;
break;
default:
LOG_ERR("%s: Invalid I2C speed rate flag: %d", __func__, I2C_SPEED_GET(dev_config));
return -EIO;
}
/* Recalc clock setting after updating config. */
calc_iic_master_clock_setting(dev, data->fsp_config.rate,
&data->iic_master_ext_cfg.clock_settings);
R_IIC_MASTER_Close(&data->ctrl);
R_IIC_MASTER_Open(&data->ctrl, &data->fsp_config);
/* save current devconfig. */
data->dev_config = dev_config;
return 0;
}
static int i2c_ra_iic_get_config(const struct device *dev, uint32_t *dev_config)
{
struct i2c_ra_iic_data *data = (struct i2c_ra_iic_data *const)dev->data;
*dev_config = data->dev_config;
return 0;
}
#define OPERATION(msg) (((struct i2c_msg *)msg)->flags & I2C_MSG_RW_MASK)
static int i2c_ra_iic_transfer(const struct device *dev, struct i2c_msg *msgs, uint8_t num_msgs,
uint16_t addr)
{
struct i2c_ra_iic_data *data = (struct i2c_ra_iic_data *const)dev->data;
struct i2c_msg *current, *next;
fsp_err_t fsp_err = FSP_SUCCESS;
int ret = 0;
if (!num_msgs) {
return 0;
}
/* Check for validity of all messages before transfer */
current = msgs;
/*
* Set I2C_MSG_RESTART flag on first message in order to send start
* condition
*/
current->flags |= I2C_MSG_RESTART;
for (int i = 1; i <= num_msgs; i++) {
if (i < num_msgs) {
next = current + 1;
/*
* Restart condition between messages
* of different directions is required
*/
if (OPERATION(current) != OPERATION(next)) {
if (!(next->flags & I2C_MSG_RESTART)) {
LOG_ERR("%s: Restart condition between messages of "
"different directions is required."
"Current/Total: [%d/%d]",
__func__, i, num_msgs);
ret = -EIO;
break;
}
}
/* Stop condition is only allowed on last message */
if (current->flags & I2C_MSG_STOP) {
LOG_ERR("%s: Invalid stop flag. Stop condition is only allowed on "
"last message. "
"Current/Total: [%d/%d]",
__func__, i, num_msgs);
ret = -EIO;
break;
}
} else {
current->flags |= I2C_MSG_STOP;
}
current++;
}
if (ret) {
return ret;
}
k_mutex_lock(&data->bus_mutex, K_FOREVER);
/* Set destination address with configured address mode before sending msg. */
i2c_master_addr_mode_t addr_mode = 0;
if (I2C_MSG_ADDR_10_BITS & data->dev_config) {
addr_mode = I2C_MASTER_ADDR_MODE_10BIT;
} else {
addr_mode = I2C_MASTER_ADDR_MODE_7BIT;
}
R_IIC_MASTER_SlaveAddressSet(&data->ctrl, addr, addr_mode);
/* Process input `msgs`. */
current = msgs;
while (num_msgs > 0) {
if (num_msgs > 1) {
next = current + 1;
} else {
next = NULL;
}
if (current->flags & I2C_MSG_READ) {
fsp_err =
R_IIC_MASTER_Read(&data->ctrl, current->buf, current->len,
next != NULL && (next->flags & I2C_MSG_RESTART));
} else {
fsp_err =
R_IIC_MASTER_Write(&data->ctrl, current->buf, current->len,
next != NULL && (next->flags & I2C_MSG_RESTART));
}
if (fsp_err != FSP_SUCCESS) {
switch (fsp_err) {
case FSP_ERR_INVALID_SIZE:
LOG_ERR("%s: Provided number of bytes more than uint16_t size "
"(65535) while DTC is used for data transfer.",
__func__);
break;
case FSP_ERR_IN_USE:
LOG_ERR("%s: Bus busy condition. Another transfer was in progress.",
__func__);
break;
default:
/* Should not reach here. */
LOG_ERR("%s: Unknown error. FSP_ERR=%d\n", __func__, fsp_err);
break;
}
ret = -EIO;
goto RELEASE_BUS;
}
/* Wait for callback to return. */
k_sem_take(&data->complete_sem, K_FOREVER);
/* Handle event msg from callback. */
switch (data->event) {
case I2C_MASTER_EVENT_ABORTED:
LOG_ERR("%s: %s failed.", __func__,
(current->flags & I2C_MSG_READ) ? "Read" : "Write");
ret = -EIO;
goto RELEASE_BUS;
case I2C_MASTER_EVENT_RX_COMPLETE:
break;
case I2C_MASTER_EVENT_TX_COMPLETE:
break;
default:
break;
}
current++;
num_msgs--;
}
RELEASE_BUS:
k_mutex_unlock(&data->bus_mutex);
return ret;
}
static void i2c_ra_iic_callback(i2c_master_callback_args_t *p_args)
{
const struct device *dev = p_args->p_context;
struct i2c_ra_iic_data *data = dev->data;
data->event = p_args->event;
k_sem_give(&data->complete_sem);
}
static int i2c_ra_iic_init(const struct device *dev)
{
const struct i2c_ra_iic_config *config = dev->config;
struct i2c_ra_iic_data *data = (struct i2c_ra_iic_data *)dev->data;
fsp_err_t fsp_err = FSP_SUCCESS;
int ret = 0;
/* Configure dt provided device signals when available */
ret = pinctrl_apply_state(config->pcfg, PINCTRL_STATE_DEFAULT);
if (ret < 0) {
LOG_ERR("%s: pinctrl config failed.", __func__);
return ret;
}
k_mutex_init(&data->bus_mutex);
k_sem_init(&data->complete_sem, 0, 1);
switch (data->fsp_config.rate) {
case I2C_MASTER_RATE_STANDARD:
case I2C_MASTER_RATE_FAST:
case I2C_MASTER_RATE_FASTPLUS:
calc_iic_master_clock_setting(dev, data->fsp_config.rate,
&data->iic_master_ext_cfg.clock_settings);
data->iic_master_ext_cfg.timeout_mode = IIC_MASTER_TIMEOUT_MODE_SHORT;
data->iic_master_ext_cfg.timeout_scl_low = IIC_MASTER_TIMEOUT_SCL_LOW_ENABLED;
data->fsp_config.p_extend = &data->iic_master_ext_cfg;
break;
default:
LOG_ERR("%s: Invalid I2C speed rate: %d", __func__, data->fsp_config.rate);
return -ENOTSUP;
}
fsp_err = R_IIC_MASTER_Open(&data->ctrl, &data->fsp_config);
__ASSERT(fsp_err == FSP_SUCCESS, "%s: Open iic master failed. FSP_ERR=%d", __func__,
fsp_err);
config->irq_config_func(dev);
return 0;
}
static void calc_iic_master_bitrate(const struct i2c_ra_iic_config *config, uint32_t total_brl_brh,
uint32_t brh, uint32_t divider,
struct ra_iic_master_bitrate *result)
{
const uint32_t noise_filter_stage = config->noise_filter_stage;
const double rise_time_s = config->rise_time_s;
const double fall_time_s = config->fall_time_s;
const uint32_t requested_duty = config->duty_cycle_percent;
const uint32_t peripheral_clock = R_FSP_SystemClockHzGet(FSP_PRIV_CLOCK_PCLKB);
uint32_t constant_add = 0;
/* A constant is added to BRL and BRH in all formulas. This constand is 3 + nf
* when CKS == 0, or 2 + nf when CKS != 0.
*/
if (divider == 0) {
constant_add = 3 + noise_filter_stage;
} else {
/* All dividers other than 0 use an addition of 2 + noise_filter_stages. */
constant_add = 2 + noise_filter_stage;
}
/* Converts all divided numbers to double to avoid data loss. */
uint32_t divided_pclk = (peripheral_clock >> divider);
result->bitrate =
1 / ((total_brl_brh + 2 * constant_add) / divided_pclk + rise_time_s + fall_time_s);
result->duty =
100 *
((rise_time_s + ((brh + constant_add) / divided_pclk)) /
(rise_time_s + fall_time_s + ((total_brl_brh + 2 * constant_add)) / divided_pclk));
result->divider = divider;
result->brh = brh;
result->brl = total_brl_brh - brh;
result->duty_error_percent =
(result->duty > requested_duty ? result->duty - requested_duty
: requested_duty - result->duty) /
requested_duty;
LOG_DBG("%s: [input] total_brl_brh[%d] brh[%d] divider[%d]"
" [output] bitrate[%u] duty[%u] divider[%u] brh[%u] brl[%u] "
"duty_error_percent[%u]\n",
__func__, total_brl_brh, brh, divider, result->bitrate, result->duty,
result->divider, result->brh, result->brl, result->duty_error_percent);
}
static void calc_iic_master_clock_setting(const struct device *dev, const uint32_t fsp_i2c_rate,
iic_master_clock_settings_t *clk_cfg)
{
const struct i2c_ra_iic_config *config = dev->config;
const uint32_t noise_filter_stage = config->noise_filter_stage;
const double rise_time_s = config->rise_time_s;
const double fall_time_s = config->fall_time_s;
const uint32_t requested_duty = config->duty_cycle_percent;
const uint32_t peripheral_clock = R_FSP_SystemClockHzGet(FSP_PRIV_CLOCK_PCLKB);
uint32_t requested_bitrate = 0;
switch (fsp_i2c_rate) {
case I2C_MASTER_RATE_STANDARD:
case I2C_MASTER_RATE_FAST:
case I2C_MASTER_RATE_FASTPLUS:
requested_bitrate = fsp_i2c_rate;
break;
default:
LOG_ERR("%s: Invalid I2C speed rate: %d", __func__, fsp_i2c_rate);
return;
}
/* Start with maximum possible bitrate. */
uint32_t min_brh = noise_filter_stage + 1;
uint32_t min_brl_brh = 2 * min_brh;
struct ra_iic_master_bitrate bitrate = {};
calc_iic_master_bitrate(config, min_brl_brh, min_brh, 0, &bitrate);
/* Start with the smallest divider because it gives the most resolution. */
uint32_t constant_add = 3 + noise_filter_stage;
for (int temp_divider = 0; temp_divider <= 7; ++temp_divider) {
if (1 == temp_divider) {
/* All dividers other than 0 use an addition of 2 + noise_filter_stages.
*/
constant_add = 2 + noise_filter_stage;
}
/* If the requested bitrate cannot be achieved with this divider, continue.
*/
uint32_t divided_pclk = (peripheral_clock >> temp_divider);
uint32_t total_brl_brh =
ceil(((1 / (double)requested_bitrate) - (rise_time_s + fall_time_s)) *
divided_pclk -
(2 * constant_add));
if ((total_brl_brh > 62) || (total_brl_brh < min_brl_brh)) {
continue;
}
uint32_t temp_brh = total_brl_brh * requested_duty / 100;
if (temp_brh < min_brh) {
temp_brh = min_brh;
}
/* Calculate the actual bitrate and duty cycle. */
struct ra_iic_master_bitrate temp_bitrate = {};
calc_iic_master_bitrate(config, total_brl_brh, temp_brh, temp_divider,
&temp_bitrate);
/* Adjust duty cycle down if it helps. */
struct ra_iic_master_bitrate test_bitrate = temp_bitrate;
while (test_bitrate.duty > requested_duty) {
temp_brh -= 1;
if ((temp_brh < min_brh) || ((total_brl_brh - temp_brh) > 31)) {
break;
}
struct ra_iic_master_bitrate new_bitrate = {};
calc_iic_master_bitrate(config, total_brl_brh, temp_brh, temp_divider,
&new_bitrate);
if (new_bitrate.duty_error_percent < temp_bitrate.duty_error_percent) {
temp_bitrate = new_bitrate;
} else {
break;
}
}
/* Adjust duty cycle up if it helps. */
while (test_bitrate.duty < requested_duty) {
++temp_brh;
if ((temp_brh > total_brl_brh) || (temp_brh > 31) ||
((total_brl_brh - temp_brh) < min_brh)) {
break;
}
struct ra_iic_master_bitrate new_bitrate = {};
calc_iic_master_bitrate(config, total_brl_brh, temp_brh, temp_divider,
&new_bitrate);
if (new_bitrate.duty_error_percent < temp_bitrate.duty_error_percent) {
temp_bitrate = new_bitrate;
} else {
break;
}
}
if ((temp_bitrate.brh < 32) && (temp_bitrate.brl < 32)) {
/* Valid setting found. */
bitrate = temp_bitrate;
break;
}
}
clk_cfg->brl_value = bitrate.brl;
clk_cfg->brh_value = bitrate.brh;
clk_cfg->cks_value = bitrate.divider;
LOG_DBG("%s: [input] rate[%u] [output] brl[%u] brh[%u] cks[%u]\n", __func__, fsp_i2c_rate,
clk_cfg->brl_value, clk_cfg->brh_value, clk_cfg->cks_value);
}
static const struct i2c_driver_api i2c_ra_iic_driver_api = {
.configure = i2c_ra_iic_configure,
.get_config = i2c_ra_iic_get_config,
.transfer = i2c_ra_iic_transfer,
};
#define _ELC_EVENT_IIC_RXI(channel) ELC_EVENT_IIC##channel##_RXI
#define _ELC_EVENT_IIC_TXI(channel) ELC_EVENT_IIC##channel##_TXI
#define _ELC_EVENT_IIC_TEI(channel) ELC_EVENT_IIC##channel##_TEI
#define _ELC_EVENT_IIC_ERI(channel) ELC_EVENT_IIC##channel##_ERI
#define ELC_EVENT_IIC_RXI(channel) _ELC_EVENT_IIC_RXI(channel)
#define ELC_EVENT_IIC_TXI(channel) _ELC_EVENT_IIC_TXI(channel)
#define ELC_EVENT_IIC_TEI(channel) _ELC_EVENT_IIC_TEI(channel)
#define ELC_EVENT_IIC_ERI(channel) _ELC_EVENT_IIC_ERI(channel)
#define I2C_RA_IIC_INIT(index) \
\
PINCTRL_DT_INST_DEFINE(index); \
\
static void i2c_ra_iic_irq_config_func##index(const struct device *dev) \
{ \
R_ICU->IELSR[DT_INST_IRQ_BY_NAME(index, rxi, irq)] = \
ELC_EVENT_IIC_RXI(DT_INST_PROP(index, channel)); \
R_ICU->IELSR[DT_INST_IRQ_BY_NAME(index, txi, irq)] = \
ELC_EVENT_IIC_TXI(DT_INST_PROP(index, channel)); \
R_ICU->IELSR[DT_INST_IRQ_BY_NAME(index, tei, irq)] = \
ELC_EVENT_IIC_TEI(DT_INST_PROP(index, channel)); \
R_ICU->IELSR[DT_INST_IRQ_BY_NAME(index, eri, irq)] = \
ELC_EVENT_IIC_ERI(DT_INST_PROP(index, channel)); \
\
IRQ_CONNECT(DT_INST_IRQ_BY_NAME(index, rxi, irq), \
DT_INST_IRQ_BY_NAME(index, rxi, priority), iic_master_rxi_isr, \
DEVICE_DT_INST_GET(index), 0); \
IRQ_CONNECT(DT_INST_IRQ_BY_NAME(index, txi, irq), \
DT_INST_IRQ_BY_NAME(index, txi, priority), iic_master_txi_isr, \
DEVICE_DT_INST_GET(index), 0); \
IRQ_CONNECT(DT_INST_IRQ_BY_NAME(index, tei, irq), \
DT_INST_IRQ_BY_NAME(index, tei, priority), iic_master_tei_isr, \
DEVICE_DT_INST_GET(index), 0); \
IRQ_CONNECT(DT_INST_IRQ_BY_NAME(index, eri, irq), \
DT_INST_IRQ_BY_NAME(index, eri, priority), iic_master_eri_isr, \
DEVICE_DT_INST_GET(index), 0); \
\
irq_enable(DT_INST_IRQ_BY_NAME(index, rxi, irq)); \
irq_enable(DT_INST_IRQ_BY_NAME(index, txi, irq)); \
irq_enable(DT_INST_IRQ_BY_NAME(index, tei, irq)); \
irq_enable(DT_INST_IRQ_BY_NAME(index, eri, irq)); \
} \
\
static const struct i2c_ra_iic_config i2c_ra_iic_config_##index = { \
.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(index), \
.irq_config_func = i2c_ra_iic_irq_config_func##index, \
.noise_filter_stage = 1, /* Cannot be configured. */ \
.rise_time_s = DT_INST_PROP(index, rise_time_ns) / RA_IIC_MASTER_DIV_TIME_NS, \
.fall_time_s = DT_INST_PROP(index, fall_time_ns) / RA_IIC_MASTER_DIV_TIME_NS, \
.duty_cycle_percent = DT_INST_PROP(index, duty_cycle_percent), \
}; \
\
static struct i2c_ra_iic_data i2c_ra_iic_data_##index = { \
.fsp_config = \
{ \
.channel = DT_INST_PROP(index, channel), \
.slave = 0, \
.rate = DT_INST_PROP(index, clock_frequency), \
.addr_mode = I2C_MASTER_ADDR_MODE_7BIT, \
.ipl = DT_INST_PROP(index, interrupt_priority_level), \
.rxi_irq = DT_INST_IRQ_BY_NAME(index, rxi, irq), \
.txi_irq = DT_INST_IRQ_BY_NAME(index, txi, irq), \
.tei_irq = DT_INST_IRQ_BY_NAME(index, tei, irq), \
.eri_irq = DT_INST_IRQ_BY_NAME(index, eri, irq), \
.p_callback = i2c_ra_iic_callback, \
.p_context = DEVICE_DT_GET(DT_DRV_INST(index)), \
}, \
}; \
\
I2C_DEVICE_DT_INST_DEFINE(index, i2c_ra_iic_init, NULL, &i2c_ra_iic_data_##index, \
&i2c_ra_iic_config_##index, POST_KERNEL, \
CONFIG_I2C_INIT_PRIORITY, &i2c_ra_iic_driver_api);
DT_INST_FOREACH_STATUS_OKAY(I2C_RA_IIC_INIT)