fix(i2c): Ensure that semaphore is properly given if init fails (#10313)

me-no-dev · web-flow · commit 2c4ce95e16a0 · 2024-09-10T16:18:16.000+03:00
Currently code can return before semaphore is given, which can cause the bus to lock. Change makes sure that it's properly given in case of failure.
diff --git a/cores/esp32/esp32-hal-i2c.c b/cores/esp32/esp32-hal-i2c.c
@@ -71,6 +71,7 @@ bool i2cIsInit(uint8_t i2c_num) {
 }
 
 esp_err_t i2cInit(uint8_t i2c_num, int8_t sda, int8_t scl, uint32_t frequency) {
+  esp_err_t ret = ESP_OK;
   if (i2c_num >= SOC_I2C_NUM) {
     return ESP_ERR_INVALID_ARG;
   }
@@ -90,7 +91,8 @@ esp_err_t i2cInit(uint8_t i2c_num, int8_t sda, int8_t scl, uint32_t frequency) {
 #endif
   if (bus[i2c_num].initialized) {
     log_e("bus is already initialized");
-    return ESP_FAIL;
+    ret = ESP_FAIL;
+    goto init_fail;
   }
 
   if (!frequency) {
@@ -103,7 +105,8 @@ esp_err_t i2cInit(uint8_t i2c_num, int8_t sda, int8_t scl, uint32_t frequency) {
   perimanSetBusDeinit(ESP32_BUS_TYPE_I2C_MASTER_SCL, i2cDetachBus);
 
   if (!perimanClearPinBus(sda) || !perimanClearPinBus(scl)) {
-    return false;
+    ret = ESP_FAIL;
+    goto init_fail;
   }
 
   log_i("Initializing I2C Master: sda=%d scl=%d freq=%d", sda, scl, frequency);
@@ -117,7 +120,7 @@ esp_err_t i2cInit(uint8_t i2c_num, int8_t sda, int8_t scl, uint32_t frequency) {
   conf.master.clk_speed = frequency;
   conf.clk_flags = I2C_SCLK_SRC_FLAG_FOR_NOMAL;  //Any one clock source that is available for the specified frequency may be chosen
 
-  esp_err_t ret = i2c_param_config((i2c_port_t)i2c_num, &conf);
+  ret = i2c_param_config((i2c_port_t)i2c_num, &conf);
   if (ret != ESP_OK) {
     log_e("i2c_param_config failed");
   } else {
@@ -133,11 +136,16 @@ esp_err_t i2cInit(uint8_t i2c_num, int8_t sda, int8_t scl, uint32_t frequency) {
       i2c_set_timeout((i2c_port_t)i2c_num, I2C_LL_MAX_TIMEOUT);
       if (!perimanSetPinBus(sda, ESP32_BUS_TYPE_I2C_MASTER_SDA, (void *)(i2c_num + 1), i2c_num, -1)
           || !perimanSetPinBus(scl, ESP32_BUS_TYPE_I2C_MASTER_SCL, (void *)(i2c_num + 1), i2c_num, -1)) {
+#if !CONFIG_DISABLE_HAL_LOCKS
+        //release lock so that i2cDetachBus can execute i2cDeinit
+        xSemaphoreGive(bus[i2c_num].lock);
+#endif
         i2cDetachBus((void *)(i2c_num + 1));
-        return false;
+        return ESP_FAIL;
       }
     }
   }
+init_fail:
 #if !CONFIG_DISABLE_HAL_LOCKS
   //release lock
   xSemaphoreGive(bus[i2c_num].lock);
