/* * Copyright (c) 2024 Renesas Electronics Corporation * * SPDX-License-Identifier: Apache-2.0 */ #define DT_DRV_COMPAT renesas_ra_iic #include #include #include #include #include #include #include #include "r_iic_master.h" #include #include #include 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 DEVICE_API(i2c, 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)