/* * The MIT License (MIT) * * Copyright (c) 2018 Ruslan V. Uss * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ /** * @file i2cdev.c * * ESP-IDF I2C master thread-safe functions for communication with I2C slave * * Copyright (C) 2018 Ruslan V. Uss * Updated 2025 by quinkq to use newer ESP-IDF I2C master driver API * * MIT Licensed as described in the file LICENSE */ #include "i2cdev.h" #include #include #include #include #include #include static const char *TAG = "i2cdev"; // Fallback definition for platforms without 10-bit address support #ifndef I2C_ADDR_BIT_LEN_10 #define I2C_ADDR_BIT_LEN_10 1 #endif #define I2C_DEFAULT_FREQ_HZ 400000 #define I2C_MAX_RETRIES 3 #define I2C_RETRY_BASE_DELAY_MS 20 #define I2CDEV_MAX_STACK_ALLOC_SIZE 32 // Stack allocation threshold to avoid heap fragmentation for small buffers typedef struct { SemaphoreHandle_t lock; // Mutex for exclusive access to this port's state i2c_master_bus_handle_t bus_handle; // Handle to the initialized I2C master bus bool installed; // Flag indicating if the bus for this port has been installed uint32_t ref_count; // Number of devices currently active on this bus port int sda_pin_current; // Actual SDA pin the bus was initialized with int scl_pin_current; // Actual SCL pin the bus was initialized with } i2c_port_state_t; static i2c_port_state_t i2c_ports[I2C_NUM_MAX] = { 0 }; static i2c_dev_t *active_devices[I2C_NUM_MAX][CONFIG_I2CDEV_MAX_DEVICES_PER_PORT] = { { NULL } }; // Helper to register a device static esp_err_t register_device(i2c_dev_t *dev) { if (!dev) return ESP_ERR_INVALID_ARG; int port = dev->port; if (port >= I2C_NUM_MAX) return ESP_ERR_INVALID_ARG; // Note: Port mutex should be held by caller for (int i = 0; i < CONFIG_I2CDEV_MAX_DEVICES_PER_PORT; i++) { if (active_devices[port][i] == NULL) { active_devices[port][i] = dev; ESP_LOGV(TAG, "[0x%02x at %d] Registered device in slot %d", dev->addr, port, i); return ESP_OK; } } ESP_LOGE(TAG, "[0x%02x at %d] No free slots to register device - limit reached", dev->addr, port); return ESP_ERR_NO_MEM; } // Helper to deregister a device static void deregister_device(i2c_dev_t *dev) { if (!dev) return; int port = dev->port; if (port >= I2C_NUM_MAX) return; for (int i = 0; i < CONFIG_I2CDEV_MAX_DEVICES_PER_PORT; i++) { if (active_devices[port][i] == dev) { active_devices[port][i] = NULL; ESP_LOGV(TAG, "[0x%02x at %d] Deregistered device from slot %d", dev->addr, port, i); return; } } } esp_err_t i2cdev_init(void) { ESP_LOGV(TAG, "Initializing I2C subsystem..."); memset(active_devices, 0, sizeof(active_devices)); for (int i = 0; i < I2C_NUM_MAX; i++) { if (!i2c_ports[i].lock) { i2c_ports[i].lock = xSemaphoreCreateMutex(); if (!i2c_ports[i].lock) { ESP_LOGE(TAG, "Could not create port mutex %d", i); return ESP_ERR_NO_MEM; } ESP_LOGV(TAG, "Created port mutex %d", i); } i2c_ports[i].installed = false; i2c_ports[i].ref_count = 0; i2c_ports[i].bus_handle = NULL; i2c_ports[i].sda_pin_current = -1; i2c_ports[i].scl_pin_current = -1; } ESP_LOGV(TAG, "I2C subsystem initialized."); return ESP_OK; } esp_err_t i2c_dev_create_mutex(i2c_dev_t *dev) { #if !CONFIG_I2CDEV_NOLOCK if (!dev) return ESP_ERR_INVALID_ARG; ESP_LOGV(TAG, "[0x%02x at %d] Creating device mutex...", dev->addr, dev->port); if (dev->mutex) { ESP_LOGW(TAG, "[0x%02x at %d] device mutex already exists (Handle: %p)", dev->addr, dev->port, dev->mutex); return ESP_OK; // Already created } dev->mutex = xSemaphoreCreateMutex(); if (!dev->mutex) { ESP_LOGE(TAG, "[0x%02x at %d] Could not create device mutex", dev->addr, dev->port); return ESP_ERR_NO_MEM; // Use ESP_ERR_NO_MEM for memory allocation failures } ESP_LOGV(TAG, "[0x%02x at %d] Device mutex created (Handle: %p)", dev->addr, dev->port, dev->mutex); // Register the device for cleanup tracking (under port mutex for consistency) if (dev->port < I2C_NUM_MAX && i2c_ports[dev->port].lock) { if (xSemaphoreTake(i2c_ports[dev->port].lock, pdMS_TO_TICKS(CONFIG_I2CDEV_TIMEOUT)) == pdTRUE) { esp_err_t reg_res = register_device(dev); if (reg_res != ESP_OK) { ESP_LOGW(TAG, "[0x%02x at %d] Failed to register device: %s - device will work but cleanup tracking disabled", dev->addr, dev->port, esp_err_to_name(reg_res)); // Continue - device can still function without registration tracking } else { ESP_LOGV(TAG, "[0x%02x at %d] Device registered successfully for cleanup tracking", dev->addr, dev->port); } xSemaphoreGive(i2c_ports[dev->port].lock); } else { ESP_LOGW(TAG, "[0x%02x at %d] Could not take port mutex for device registration", dev->addr, dev->port); // Continue - device can still function without registration tracking } } // Set default address bit length if not explicitly set if (dev->addr_bit_len != I2C_ADDR_BIT_LEN_7 && dev->addr_bit_len != I2C_ADDR_BIT_LEN_10) { ESP_LOGV(TAG, "[0x%02x at %d] Setting default 7-bit address format", dev->addr, dev->port); dev->addr_bit_len = I2C_ADDR_BIT_LEN_7; } #else ESP_LOGV(TAG, "[0x%02x at %d] Mutex creation skipped (CONFIG_I2CDEV_NOLOCK=1)", dev->addr, dev->port); #endif return ESP_OK; } esp_err_t i2c_dev_delete_mutex(i2c_dev_t *dev) { #if !CONFIG_I2CDEV_NOLOCK if (!dev) return ESP_ERR_INVALID_ARG; ESP_LOGV(TAG, "[0x%02x at %d] Deleting device mutex and cleaning up resources", dev->addr, dev->port); // Remove device from bus if handle exists if (dev->dev_handle) { ESP_LOGV(TAG, "[0x%02x at %d] Removing device handle %p from bus", dev->addr, dev->port, dev->dev_handle); esp_err_t rm_res = i2c_master_bus_rm_device((i2c_master_dev_handle_t)dev->dev_handle); if (rm_res != ESP_OK) { ESP_LOGW(TAG, "[0x%02x at %d] Failed to remove device handle: %s", dev->addr, dev->port, esp_err_to_name(rm_res)); // Continue with cleanup despite error } dev->dev_handle = NULL; } // Deregister the device deregister_device(dev); // Update port reference count if port is valid if (dev->port < I2C_NUM_MAX) { if (xSemaphoreTake(i2c_ports[dev->port].lock, pdMS_TO_TICKS(CONFIG_I2CDEV_TIMEOUT)) == pdTRUE) { if (i2c_ports[dev->port].installed && i2c_ports[dev->port].ref_count > 0) { i2c_ports[dev->port].ref_count--; ESP_LOGV(TAG, "[Port %d] Decremented ref_count to %" PRIu32, dev->port, i2c_ports[dev->port].ref_count); // If last device on this port, delete the bus if (i2c_ports[dev->port].ref_count == 0) { ESP_LOGI(TAG, "[Port %d] Last device removed, cleaning up THIS port's bus", dev->port); // Just clean up this port's bus if (i2c_ports[dev->port].bus_handle) { ESP_LOGI(TAG, "[Port %d] Deleting bus handle %p", dev->port, i2c_ports[dev->port].bus_handle); esp_err_t del_bus_res = i2c_del_master_bus(i2c_ports[dev->port].bus_handle); if (del_bus_res != ESP_OK) { ESP_LOGE(TAG, "[Port %d] Failed to delete master bus: %s", dev->port, esp_err_to_name(del_bus_res)); } i2c_ports[dev->port].bus_handle = NULL; } i2c_ports[dev->port].installed = false; i2c_ports[dev->port].sda_pin_current = -1; i2c_ports[dev->port].scl_pin_current = -1; } } xSemaphoreGive(i2c_ports[dev->port].lock); } else { ESP_LOGW(TAG, "[0x%02x at %d] Could not take port mutex for ref_count update", dev->addr, dev->port); } } // Delete the mutex itself last if (dev->mutex) { vSemaphoreDelete(dev->mutex); dev->mutex = NULL; } else { ESP_LOGV(TAG, "[0x%02x at %d] Device mutex was NULL, nothing to delete", dev->addr, dev->port); } #endif return ESP_OK; } esp_err_t i2c_dev_take_mutex(i2c_dev_t *dev) { #if !CONFIG_I2CDEV_NOLOCK if (!dev) return ESP_ERR_INVALID_ARG; ESP_LOGV(TAG, "[0x%02x at %d] Attempting to take device mutex (Handle: %p)...", dev->addr, dev->port, dev->mutex); if (!dev->mutex) { ESP_LOGE(TAG, "[0x%02x at %d] Attempt to take NULL device mutex!", dev->addr, dev->port); return ESP_ERR_INVALID_STATE; // Mutex doesn't exist } TickType_t timeout_ticks = pdMS_TO_TICKS(CONFIG_I2CDEV_TIMEOUT); ESP_LOGV(TAG, "[0x%02x at %d] Taking device mutex with timeout %d ms (%lu ticks)", dev->addr, dev->port, CONFIG_I2CDEV_TIMEOUT, (unsigned long)timeout_ticks); if (!xSemaphoreTake(dev->mutex, timeout_ticks)) { ESP_LOGE(TAG, "[0x%02x at %d] Could not take device mutex (Timeout after %d ms)", dev->addr, dev->port, CONFIG_I2CDEV_TIMEOUT); return ESP_ERR_TIMEOUT; } ESP_LOGV(TAG, "[0x%02x at %d] Device mutex taken successfully.", dev->addr, dev->port); #else ESP_LOGV(TAG, "[0x%02x at %d] Mutex take skipped (CONFIG_I2CDEV_NOLOCK=1)", dev->addr, dev->port); #endif return ESP_OK; } esp_err_t i2c_dev_give_mutex(i2c_dev_t *dev) { #if !CONFIG_I2CDEV_NOLOCK if (!dev) return ESP_ERR_INVALID_ARG; ESP_LOGV(TAG, "[0x%02x at %d] Giving device mutex (Handle: %p)...", dev->addr, dev->port, dev->mutex); if (!dev->mutex) { ESP_LOGE(TAG, "[0x%02x at %d] Attempt to give NULL device mutex!", dev->addr, dev->port); return ESP_ERR_INVALID_STATE; } if (!xSemaphoreGive(dev->mutex)) { // This case should ideally not happen if the mutex was taken correctly ESP_LOGE(TAG, "[0x%02x at %d] Could not give device mutex (Was it taken?) (Handle: %p)", dev->addr, dev->port, dev->mutex); return ESP_FAIL; } ESP_LOGV(TAG, "[0x%02x at %d] Device mutex given successfully.", dev->addr, dev->port); #else ESP_LOGV(TAG, "[0x%02x at %d] Mutex give skipped (CONFIG_I2CDEV_NOLOCK=1)", dev->addr, dev->port); #endif return ESP_OK; } // i2c_setup_port: Initializes the I2C master bus for a given port if not already done. // It uses pin configurations from dev->cfg.sda_io_num and dev->cfg.scl_io_num. // The pins for a port are fixed after the first device initializes it. static esp_err_t i2c_setup_port(i2c_dev_t *dev) // dev is non-const to update dev->sda_pin, dev->scl_pin { if (!dev) return ESP_ERR_INVALID_ARG; if (dev->port >= I2C_NUM_MAX) { ESP_LOGE(TAG, "Invalid I2C port number: %d", dev->port); return ESP_ERR_INVALID_ARG; } esp_err_t res = ESP_OK; i2c_port_state_t *port_state = &i2c_ports[dev->port]; ESP_LOGV(TAG, "[Port %d] Setup request for device 0x%02x", dev->port, dev->addr); if (xSemaphoreTake(port_state->lock, pdMS_TO_TICKS(CONFIG_I2CDEV_TIMEOUT)) != pdTRUE) { ESP_LOGE(TAG, "[Port %d] Could not take port mutex for setup", dev->port); return ESP_ERR_TIMEOUT; } if (!port_state->installed) { // Pin Selection Logic: Use device-specified pins, fallback to Kconfig defaults if -1 gpio_num_t sda_pin = (dev->cfg.sda_io_num == (gpio_num_t) -1) ? (gpio_num_t)CONFIG_I2CDEV_DEFAULT_SDA_PIN : dev->cfg.sda_io_num; gpio_num_t scl_pin = (dev->cfg.scl_io_num == (gpio_num_t) -1) ? (gpio_num_t)CONFIG_I2CDEV_DEFAULT_SCL_PIN : dev->cfg.scl_io_num; // Validate pins (basic check, gpio_is_valid_gpio could be used for more robust check) if (sda_pin < 0 || scl_pin < 0) { ESP_LOGE(TAG, "[Port %d] Invalid SCL/SDA pins: SDA=%d, SCL=%d. Check driver or Kconfig defaults.", dev->port, sda_pin, scl_pin); xSemaphoreGive(port_state->lock); return ESP_ERR_INVALID_ARG; } /* * OPTIONAL I2C PULLUP AUTO-CONFIGURATION * * By default: Uses whatever sda_pullup_en/scl_pullup_en you set (usually false) * * When CONFIG_I2CDEV_AUTO_ENABLE_PULLUPS=y: If both pullup flags are false, * automatically change them to true to enable internal pullups (~45kΩ). * * Manual pullup configuration: * - Set sda_pullup_en=true, scl_pullup_en=true for internal pullups * - Set sda_pullup_en=false, scl_pullup_en=false for external pullups */ // Read user's pullup configuration (default false if not set) bool sda_pullup = dev->cfg.sda_pullup_en; bool scl_pullup = dev->cfg.scl_pullup_en; #if CONFIG_I2CDEV_AUTO_ENABLE_PULLUPS // CONFIG_I2CDEV_AUTO_ENABLE_PULLUPS=y: If user didn't configure pullups, enable them automatically if (!sda_pullup && !scl_pullup) { sda_pullup = true; scl_pullup = true; ESP_LOGI(TAG, "[Port %d] Auto-enabling internal pullups (CONFIG_I2CDEV_AUTO_ENABLE_PULLUPS=y)", dev->port); } #endif ESP_LOGI(TAG, "[Port %d] First initialization. Configuring bus with SDA=%d, SCL=%d (Pullups " "SCL:%d SDA:%d)", dev->port, sda_pin, scl_pin, scl_pullup, sda_pullup); i2c_master_bus_config_t bus_config = { .i2c_port = dev->port, .sda_io_num = sda_pin, .scl_io_num = scl_pin, .clk_source = I2C_CLK_SRC_DEFAULT, .glitch_ignore_cnt = 7, .flags.enable_internal_pullup = (sda_pullup || scl_pullup), // Bus speed is not set here. It's per-device or a global target for the bus can be set // if desired, but i2c_master supports per-device speeds. }; res = i2c_new_master_bus(&bus_config, &port_state->bus_handle); if (res == ESP_OK) { port_state->installed = true; port_state->ref_count = 0; // Will be incremented when a device is successfully added port_state->sda_pin_current = sda_pin; port_state->scl_pin_current = scl_pin; dev->sda_pin = sda_pin; // Update dev struct with actual pins used dev->scl_pin = scl_pin; ESP_LOGI(TAG, "[Port %d] Successfully installed I2C master bus (Handle: %p).", dev->port, port_state->bus_handle); } else { ESP_LOGE(TAG, "[Port %d] Failed to create master bus: %d (%s)", dev->port, res, esp_err_to_name(res)); port_state->installed = false; port_state->bus_handle = NULL; port_state->sda_pin_current = -1; port_state->scl_pin_current = -1; } } else { ESP_LOGV(TAG, "[Port %d] Port already installed (SDA=%d, SCL=%d, Handle: %p).", dev->port, port_state->sda_pin_current, port_state->scl_pin_current, port_state->bus_handle); // Pin Consistency Check: For subsequent devices, ensure pins match already-configured bus gpio_num_t sda_desired = (dev->cfg.sda_io_num == (gpio_num_t) -1) ? (gpio_num_t)port_state->sda_pin_current : dev->cfg.sda_io_num; gpio_num_t scl_desired = (dev->cfg.scl_io_num == (gpio_num_t) -1) ? (gpio_num_t)port_state->scl_pin_current : dev->cfg.scl_io_num; if (sda_desired != port_state->sda_pin_current || scl_desired != port_state->scl_pin_current) { ESP_LOGE(TAG, "[Port %d] Pin mismatch for device 0x%02x! Bus on SDA=%d,SCL=%d. Device wants " "SDA=%d,SCL=%d", dev->port, dev->addr, port_state->sda_pin_current, port_state->scl_pin_current, sda_desired, scl_desired); res = ESP_ERR_INVALID_STATE; // Cannot change pins for an installed bus } else { dev->sda_pin = port_state->sda_pin_current; // Update dev struct with actual pins used dev->scl_pin = port_state->scl_pin_current; } // ref_count is managed by i2c_setup_device when adding/removing device handles } xSemaphoreGive(port_state->lock); ESP_LOGV(TAG, "[Port %d] Port setup finished with res %d.", dev->port, res); return res; } // i2c_setup_device: Ensures port is set up and adds the device to the bus if not already added. // It also registers the device in active_devices for cleanup purposes. static esp_err_t i2c_setup_device(i2c_dev_t *dev) // dev is non-const - modifies dev->dev_handle, dev->addr_bit_len { if (!dev) return ESP_ERR_INVALID_ARG; ESP_LOGV(TAG, "[0x%02x at %d] Setting up device context...", dev->addr, dev->port); esp_err_t res = i2c_setup_port(dev); if (res != ESP_OK) { ESP_LOGE(TAG, "[0x%02x at %d] Port setup failed during device setup: %d (%s)", dev->addr, dev->port, res, esp_err_to_name(res)); return res; } // If addr_bit_len is not set (e.g. 0, which is invalid for i2c_addr_bit_len_t enum), default to // 7-bit. Modified to conditionally check for I2C_ADDR_BIT_LEN_10 based on hardware support if (dev->addr_bit_len != I2C_ADDR_BIT_LEN_7 #if SOC_I2C_SUPPORT_10BIT_ADDR && dev->addr_bit_len != I2C_ADDR_BIT_LEN_10 #endif ) { ESP_LOGD(TAG, "[0x%02x at %d] addr_bit_len not explicitly set, defaulting to 7-bit.", dev->addr, dev->port); dev->addr_bit_len = I2C_ADDR_BIT_LEN_7; } // Only warn about address size if the device is actually using 10-bit addressing if (dev->addr_bit_len == I2C_ADDR_BIT_LEN_7 && dev->addr > 0x7F) { ESP_LOGW(TAG, "[0x%02x at %d] Device address > 0x7F but addr_bit_len is 7-bit. Ensure address " "is correct.", dev->addr, dev->port); } #if !defined(SOC_I2C_SUPPORT_10BIT_ADDR) || !SOC_I2C_SUPPORT_10BIT_ADDR // On platforms without 10-bit support, force 7-bit addressing regardless of user setting if (dev->addr_bit_len == I2C_ADDR_BIT_LEN_10) { ESP_LOGW(TAG, "[0x%02x at %d] 10-bit addressing not supported on this platform, forcing 7-bit mode", dev->addr, dev->port); dev->addr_bit_len = I2C_ADDR_BIT_LEN_7; } #endif if (dev->dev_handle == NULL) { i2c_port_state_t *port_state = &i2c_ports[dev->port]; if (xSemaphoreTake(port_state->lock, pdMS_TO_TICKS(CONFIG_I2CDEV_TIMEOUT)) != pdTRUE) { ESP_LOGE(TAG, "[0x%02x at %d] Could not take port mutex for device add", dev->addr, dev->port); return ESP_ERR_TIMEOUT; } if (!port_state->installed || !port_state->bus_handle) { ESP_LOGE(TAG, "[0x%02x at %d] Cannot add device, bus for port %d not ready!", dev->addr, dev->port, dev->port); xSemaphoreGive(port_state->lock); return ESP_ERR_INVALID_STATE; } ESP_LOGV(TAG, "[0x%02x at %d] Adding device to bus (Bus Handle: %p)...", dev->addr, dev->port, port_state->bus_handle); uint32_t effective_dev_speed = dev->cfg.master.clk_speed; if (effective_dev_speed == 0) { ESP_LOGW(TAG, "[0x%02x at %d] Device speed (dev->cfg.master.clk_speed) is 0, using default: " "%" PRIu32 " Hz", dev->addr, dev->port, (uint32_t)I2C_DEFAULT_FREQ_HZ); effective_dev_speed = I2C_DEFAULT_FREQ_HZ; } i2c_device_config_t dev_config = { // Use the possibly modified addr_bit_len that respects hardware capabilities .dev_addr_length = dev->addr_bit_len, .device_address = dev->addr, .scl_speed_hz = effective_dev_speed, .flags.disable_ack_check = false, }; res = i2c_master_bus_add_device(port_state->bus_handle, &dev_config, (i2c_master_dev_handle_t *)&dev->dev_handle); if (res == ESP_OK) { ESP_LOGI(TAG, "[0x%02x at %d] Device added successfully (Device Handle: %p, Speed: %" PRIu32 " Hz).", dev->addr, dev->port, dev->dev_handle, effective_dev_speed); // Increment the port reference count for each device successfully added port_state->ref_count++; ESP_LOGV(TAG, "[Port %d] Incremented ref_count to %" PRIu32, dev->port, port_state->ref_count); } else { ESP_LOGE(TAG, "[0x%02x at %d] Failed to add device to bus: %d (%s)", dev->addr, dev->port, res, esp_err_to_name(res)); dev->dev_handle = NULL; } xSemaphoreGive(port_state->lock); } else { ESP_LOGV(TAG, "[0x%02x at %d] Device handle %p already exists. Skipping add.", dev->addr, dev->port, dev->dev_handle); res = ESP_OK; } ESP_LOGV(TAG, "[0x%02x at %d] Device context setup finished with res %d.", dev->addr, dev->port, res); return res; } // Helper function with retry mechanism for I2C operations static esp_err_t i2c_do_operation_with_retry(i2c_dev_t *dev, esp_err_t (*i2c_func)(i2c_master_dev_handle_t, const void *, size_t, void *, size_t, int), const void *write_buffer, size_t write_size, void *read_buffer, size_t read_size) { if (!dev) return ESP_ERR_INVALID_ARG; esp_err_t res = ESP_FAIL; int retry = 0; int timeout_ms = CONFIG_I2CDEV_TIMEOUT; ESP_LOGV(TAG, "[0x%02x at %d] Performing I2C operation (timeout %d ms)...", dev->addr, dev->port, timeout_ms); while (retry <= I2C_MAX_RETRIES) { // Ensure device is set up before each attempt, in case handle became stale or bus was reset // This is more robust if issues like bus errors or device resets occur. res = i2c_setup_device(dev); if (res != ESP_OK) { ESP_LOGE(TAG, "[0x%02x at %d] Device setup failed (Try %d): %d (%s). Retrying setup...", dev->addr, dev->port, retry, res, esp_err_to_name(res)); // No point continuing this attempt if setup fails, but the loop will retry setup. vTaskDelay(pdMS_TO_TICKS(I2C_RETRY_BASE_DELAY_MS * (1 << (retry)))); retry++; continue; } if (!dev->dev_handle) { ESP_LOGE(TAG, "[0x%02x at %d] Device handle is NULL after setup (Try %d)! Cannot perform " "operation.", dev->addr, dev->port, retry); // This indicates a persistent problem with adding the device to the bus. // No point retrying the i2c_func if handle is null. res = ESP_ERR_INVALID_STATE; vTaskDelay(pdMS_TO_TICKS(I2C_RETRY_BASE_DELAY_MS * (1 << (retry)))); retry++; continue; } ESP_LOGV(TAG, "[0x%02x at %d] Attempting I2C op (Try %d, Handle %p)", dev->addr, dev->port, retry, dev->dev_handle); res = i2c_func(dev->dev_handle, write_buffer, write_size, read_buffer, read_size, timeout_ms); if (res == ESP_OK) { ESP_LOGV(TAG, "[0x%02x at %d] I2C operation successful (Try %d).", dev->addr, dev->port, retry); return ESP_OK; } ESP_LOGW(TAG, "[0x%02x at %d] I2C op failed (Try %d, Handle %p): %d (%s).", dev->addr, dev->port, retry, dev->dev_handle, res, esp_err_to_name(res)); // Only remove handle on errors that indicate handle corruption or permanent invalidity // Don't remove on temporary errors like ESP_ERR_TIMEOUT, ESP_FAIL (NACK), etc. bool should_remove_handle = false; switch (res) { case ESP_ERR_INVALID_ARG: // Handle was likely removed by another task or is corrupted should_remove_handle = true; ESP_LOGW(TAG, "[0x%02x at %d] Invalid argument error - handle may be corrupted", dev->addr, dev->port); break; case ESP_ERR_INVALID_STATE: // I2C driver is in invalid state, handle likely needs recreation should_remove_handle = true; ESP_LOGW(TAG, "[0x%02x at %d] Invalid state error - handle may need recreation", dev->addr, dev->port); break; default: // For other errors (timeout, NACK, bus busy, etc.), keep the handle // These are usually temporary and don't require handle recreation should_remove_handle = false; ESP_LOGV(TAG, "[0x%02x at %d] Temporary error - keeping handle for retry", dev->addr, dev->port); break; } if (should_remove_handle && dev->dev_handle) { ESP_LOGW(TAG, "[0x%02x at %d] Removing potentially corrupted device handle %p after permanent error", dev->addr, dev->port, dev->dev_handle); // Try to remove the handle from the bus before nullifying esp_err_t rm_res = i2c_master_bus_rm_device(dev->dev_handle); if (rm_res != ESP_OK) { ESP_LOGW(TAG, "[0x%02x at %d] Failed to remove corrupted handle (expected): %s", dev->addr, dev->port, esp_err_to_name(rm_res)); // This is expected if the handle was already invalid - continue cleanup } dev->dev_handle = NULL; } retry++; if (retry <= I2C_MAX_RETRIES) { vTaskDelay(pdMS_TO_TICKS(I2C_RETRY_BASE_DELAY_MS * (1 << retry))); // Exponential backoff ESP_LOGW(TAG, "[0x%02x at %d] Retrying operation...", dev->addr, dev->port); } } ESP_LOGE(TAG, "[0x%02x at %d] I2C operation failed after %d retries. Last error: %d (%s)", dev->addr, dev->port, I2C_MAX_RETRIES + 1, res, esp_err_to_name(res)); return res; } // Wrapper functions for the I2C master API to use with the retry mechanism // i2c_do_operation_with_retry() needs a unified function signature for all I2C operations static esp_err_t i2c_master_transmit_wrapper(i2c_master_dev_handle_t handle, const void *write_buffer, size_t write_size, void *read_buffer, size_t read_size, int timeout_ms) { return i2c_master_transmit(handle, write_buffer, write_size, timeout_ms); } static esp_err_t i2c_master_receive_wrapper(i2c_master_dev_handle_t handle, const void *write_buffer, size_t write_size, void *read_buffer, size_t read_size, int timeout_ms) { return i2c_master_receive(handle, read_buffer, read_size, timeout_ms); } static esp_err_t i2c_master_transmit_receive_wrapper(i2c_master_dev_handle_t handle, const void *write_buffer, size_t write_size, void *read_buffer, size_t read_size, int timeout_ms) { return i2c_master_transmit_receive(handle, write_buffer, write_size, read_buffer, read_size, timeout_ms); } esp_err_t i2c_dev_read(const i2c_dev_t *dev, const void *out_data, size_t out_size, void *in_data, size_t in_size) { if (!dev || !in_data || !in_size) return ESP_ERR_INVALID_ARG; ESP_LOGV(TAG, "[0x%02x at %d] i2c_dev_read called (out_size: %u, in_size: %u)", dev->addr, dev->port, out_size, in_size); esp_err_t result = i2c_do_operation_with_retry((i2c_dev_t *)dev, // Cast to non-const for i2c_setup_device internal modifications out_data && out_size ? i2c_master_transmit_receive_wrapper : i2c_master_receive_wrapper, out_data, out_size, in_data, in_size); ESP_LOGV(TAG, "[0x%02x at %d] i2c_dev_read result: %s (%d)", dev->addr, dev->port, esp_err_to_name(result), result); return result; } esp_err_t i2c_dev_write(const i2c_dev_t *dev, const void *out_reg, size_t out_reg_size, const void *out_data, size_t out_size) { if (!dev) return ESP_ERR_INVALID_ARG; if ((!out_reg || !out_reg_size) && (!out_data || !out_size)) return ESP_ERR_INVALID_ARG; ESP_LOGV(TAG, "[0x%02x at %d] i2c_dev_write called (reg_size: %u, data_size: %u)", dev->addr, dev->port, out_reg_size, out_size); esp_err_t res; if (out_reg && out_reg_size && out_data && out_size) { size_t total_write_size = out_reg_size + out_size; // Check for overflow before proceeding if (total_write_size < out_reg_size || total_write_size < out_size) { ESP_LOGE(TAG, "[0x%02x at %d] Write size overflow: reg_size=%u + data_size=%u", dev->addr, dev->port, out_reg_size, out_size); return ESP_ERR_INVALID_ARG; } // Use stack for small buffers to avoid heap fragmentation if (total_write_size <= I2CDEV_MAX_STACK_ALLOC_SIZE) { // Use stack allocation for small buffers uint8_t stack_buf[I2CDEV_MAX_STACK_ALLOC_SIZE]; memcpy(stack_buf, out_reg, out_reg_size); memcpy(stack_buf + out_reg_size, out_data, out_size); res = i2c_do_operation_with_retry((i2c_dev_t *)dev, i2c_master_transmit_wrapper, stack_buf, total_write_size, NULL, 0); } else { uint8_t *heap_buf = malloc(total_write_size); if (!heap_buf) { ESP_LOGE(TAG, "[0x%02x at %d] Failed to allocate %u bytes for write", dev->addr, dev->port, total_write_size); return ESP_ERR_NO_MEM; } memcpy(heap_buf, out_reg, out_reg_size); memcpy(heap_buf + out_reg_size, out_data, out_size); res = i2c_do_operation_with_retry((i2c_dev_t *)dev, i2c_master_transmit_wrapper, heap_buf, total_write_size, NULL, 0); free(heap_buf); // Free buffer regardless of operation result } } else if (out_reg && out_reg_size) { res = i2c_do_operation_with_retry((i2c_dev_t *)dev, i2c_master_transmit_wrapper, out_reg, out_reg_size, NULL, 0); } else if (out_data && out_size) { res = i2c_do_operation_with_retry((i2c_dev_t *)dev, i2c_master_transmit_wrapper, out_data, out_size, NULL, 0); } else { return ESP_ERR_INVALID_ARG; // Shouldn't reach here given the earlier check } ESP_LOGV(TAG, "[0x%02x at %d] i2c_dev_write result: %s (%d)", dev->addr, dev->port, esp_err_to_name(res), res); return res; } esp_err_t i2c_dev_read_reg(const i2c_dev_t *dev, uint8_t reg, void *data, size_t size) { ESP_LOGV(TAG, "[0x%02x at %d] i2c_dev_read_reg called (reg: 0x%02x, size: %u)", dev->addr, dev->port, reg, size); return i2c_dev_read(dev, ®, 1, data, size); } esp_err_t i2c_dev_write_reg(const i2c_dev_t *dev, uint8_t reg, const void *data, size_t size) { ESP_LOGV(TAG, "[0x%02x at %d] i2c_dev_write_reg called (reg: 0x%02x, size: %u)", dev->addr, dev->port, reg, size); return i2c_dev_write(dev, ®, 1, data, size); } esp_err_t i2c_dev_check_present(const i2c_dev_t *dev_const) { if (!dev_const) return ESP_ERR_INVALID_ARG; ESP_LOGV(TAG, "[0x%02x at %d] Probing device presence...", dev_const->addr, dev_const->port); // Cast to non-const for i2c_setup_port (which may modify internal state) i2c_dev_t *dev = (i2c_dev_t *)dev_const; // Ensure the I2C port is set up before probing esp_err_t setup_res = i2c_setup_port(dev); if (setup_res != ESP_OK) { ESP_LOGE(TAG, "[0x%02x at %d] Failed to setup port for probe: %s", dev_const->addr, dev_const->port, esp_err_to_name(setup_res)); return setup_res; } // Now probe using the initialized bus if (dev_const->port < I2C_NUM_MAX && i2c_ports[dev_const->port].lock) { if (xSemaphoreTake(i2c_ports[dev_const->port].lock, pdMS_TO_TICKS(CONFIG_I2CDEV_TIMEOUT)) == pdTRUE) { if (i2c_ports[dev_const->port].installed && i2c_ports[dev_const->port].bus_handle) { // Use ESP-IDF's built-in probe function - completely non-intrusive esp_err_t probe_res = i2c_master_probe(i2c_ports[dev_const->port].bus_handle, dev_const->addr, CONFIG_I2CDEV_TIMEOUT); xSemaphoreGive(i2c_ports[dev_const->port].lock); if (probe_res == ESP_OK) { ESP_LOGV(TAG, "[0x%02x at %d] Device probe successful - device present", dev_const->addr, dev_const->port); return ESP_OK; } else { ESP_LOGV(TAG, "[0x%02x at %d] Device probe failed: %s", dev_const->addr, dev_const->port, esp_err_to_name(probe_res)); return probe_res; } } else { xSemaphoreGive(i2c_ports[dev_const->port].lock); ESP_LOGW(TAG, "[0x%02x at %d] Cannot probe - bus not ready on port %d", dev_const->addr, dev_const->port, dev_const->port); return ESP_ERR_INVALID_STATE; } } else { ESP_LOGE(TAG, "[0x%02x at %d] Could not take port mutex for probe", dev_const->addr, dev_const->port); return ESP_ERR_TIMEOUT; } } else { ESP_LOGE(TAG, "[0x%02x at %d] Invalid port or port not initialized", dev_const->addr, dev_const->port); return ESP_ERR_INVALID_ARG; } } // Compatibility wrapper for legacy code that still calls i2c_dev_probe // The new driver implementation uses i2c_master_probe which doesn't need operation_type esp_err_t i2c_dev_probe(const i2c_dev_t *dev, i2c_dev_type_t operation_type) { ESP_LOGV(TAG, "[0x%02x at %d] Legacy probe called (operation_type %d), redirecting to new implementation", dev->addr, dev->port, operation_type); return i2c_dev_check_present(dev); } // Clean up function to be called at application exit esp_err_t i2cdev_done(void) { esp_err_t result = ESP_OK; ESP_LOGV(TAG, "Cleaning up I2C subsystem (i2c_master)..."); for (int i = 0; i < I2C_NUM_MAX; i++) { if (i2c_ports[i].lock) { ESP_LOGV(TAG, "[Port %d] Cleaning up port...", i); if (xSemaphoreTake(i2c_ports[i].lock, pdMS_TO_TICKS(CONFIG_I2CDEV_TIMEOUT)) != pdTRUE) { ESP_LOGE(TAG, "[Port %d] Could not take port mutex for cleanup", i); result = ESP_FAIL; } else { if (i2c_ports[i].installed) { ESP_LOGV(TAG, "[Port %d] Removing active devices before deleting bus...", i); // Remove all registered devices for this port from the bus for (int j = 0; j < CONFIG_I2CDEV_MAX_DEVICES_PER_PORT; j++) { i2c_dev_t *dev_ptr = active_devices[i][j]; if (dev_ptr != NULL && dev_ptr->dev_handle != NULL) { ESP_LOGV(TAG, "[Port %d] Removing device 0x%02x (Handle %p)", i, dev_ptr->addr, dev_ptr->dev_handle); esp_err_t rm_res = i2c_master_bus_rm_device(dev_ptr->dev_handle); if (rm_res != ESP_OK) { ESP_LOGE(TAG, "[Port %d] Failed to remove device 0x%02x handle: %d", i, dev_ptr->addr, rm_res); // Continue cleanup despite error if (result == ESP_OK) result = rm_res; // Report first error } dev_ptr->dev_handle = NULL; } } ESP_LOGV(TAG, "[Port %d] Deleting master bus handle %p...", i, i2c_ports[i].bus_handle); esp_err_t del_res = i2c_del_master_bus(i2c_ports[i].bus_handle); if (del_res != ESP_OK) { ESP_LOGE(TAG, "[Port %d] Failed to delete I2C bus during cleanup: %d", i, del_res); if (result == ESP_OK) result = del_res; } i2c_ports[i].installed = false; i2c_ports[i].bus_handle = NULL; i2c_ports[i].ref_count = 0; } xSemaphoreGive(i2c_ports[i].lock); } // End else (mutex taken) ESP_LOGV(TAG, "[Port %d] Deleting port mutex...", i); vSemaphoreDelete(i2c_ports[i].lock); i2c_ports[i].lock = NULL; // Clear the active device list for this port memset(active_devices[i], 0, sizeof(active_devices[i])); ESP_LOGV(TAG, "[Port %d] Cleanup complete.", i); } // end if lock exists } // end for loop ESP_LOGV(TAG, "I2C subsystem cleanup finished with result: %d", result); return result; }