AXP192 low level I2C mutexing

include/power.h

@@ -19,6 +19,8 @@ void power_event_IRQ(void);
 void AXP192_power(bool on);
 void AXP192_init(void);
 void AXP192_showstatus(void);
+uint8_t i2c_writeBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len);
+uint8_t i2c_readBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len);
 #endif // HAS_PMU
 
 #endif

src/power.cpp

@@ -11,12 +11,7 @@ AXP20X_Class pmu;
 
 void power_event_IRQ(void) {
 
-  if (!I2C_MUTEX_LOCK())
-    ESP_LOGW(TAG, "[%0.3f] i2c mutex lock failed", millis() / 1000.0);
-  else {
-
   pmu.readIRQ();
-    // put your power event handler code here
 
   if (pmu.isVbusOverVoltageIRQ())
     ESP_LOGI(TAG, "USB voltage %.2fV too high.", pmu.getVbusVoltage() / 1000);
@@ -51,8 +46,6 @@ void power_event_IRQ(void) {
   }
 
   pmu.clearIRQ();
-    I2C_MUTEX_UNLOCK();
-  } // mutex
 
   // refresh stored voltage value
   read_voltage();
@@ -75,10 +68,6 @@ void AXP192_power(bool on) {
 
 void AXP192_showstatus(void) {
 
-  if (!I2C_MUTEX_LOCK())
-    ESP_LOGW(TAG, "[%0.3f] i2c mutex lock failed", millis() / 1000.0);
-  else {
-
   if (pmu.isBatteryConnect())
     if (pmu.isChargeing())
       ESP_LOGI(TAG, "Battery charging, %.2fV @ %.0fmAh",
@@ -93,17 +82,11 @@ void AXP192_showstatus(void) {
              pmu.getVbusVoltage() / 1000 * pmu.getVbusCurrent());
   else
     ESP_LOGI(TAG, "USB not present");
-
-    I2C_MUTEX_UNLOCK();
-  } // mutex
 }
 
 void AXP192_init(void) {
 
-  // block i2c bus access
+  if (pmu.begin(i2c_readBytes, i2c_writeBytes, AXP192_PRIMARY_ADDRESS) == AXP_FAIL)
-  if (I2C_MUTEX_LOCK()) {
-
-    if (pmu.begin(Wire, AXP192_PRIMARY_ADDRESS))
     ESP_LOGI(TAG, "AXP192 PMU initialization failed");
   else {
 
@@ -121,8 +104,6 @@ void AXP192_init(void) {
     // switch power rails on
     AXP192_power(true);
 
-      // I2C access of AXP202X library currently is not mutexable
-      // so we better should disable AXP interrupts... ?
 #ifdef PMU_INT
     pinMode(PMU_INT, INPUT_PULLUP);
     attachInterrupt(digitalPinToInterrupt(PMU_INT), PMUIRQ, FALLING);
@@ -135,10 +116,55 @@ void AXP192_init(void) {
 
     ESP_LOGI(TAG, "AXP192 PMU initialized");
   }
-    I2C_MUTEX_UNLOCK(); // release i2c bus access
-  } else
-    ESP_LOGE(TAG, "I2c bus busy - PMU initialization error");
 }
+
+// helper functions for mutexing i2c access
+uint8_t i2c_readBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len) {
+  if (I2C_MUTEX_LOCK()) {
+
+    uint8_t ret = 0;
+    Wire.beginTransmission(addr);
+    Wire.write(reg);
+    Wire.endTransmission(false);
+    uint8_t cnt = Wire.requestFrom(addr, (uint8_t)len, (uint8_t)1);
+    if (!cnt) {
+      ret = 0xFF;
+    }
+    uint16_t index = 0;
+    while (Wire.available()) {
+      if (index > len)
+        return 0xFF;
+      data[index++] = Wire.read();
+    }
+
+    I2C_MUTEX_UNLOCK(); // release i2c bus access
+    return ret;
+  } else {
+    ESP_LOGW(TAG, "[%0.3f] i2c mutex lock failed", millis() / 1000.0);
+    return 0xFF;
+  }
+}
+
+uint8_t i2c_writeBytes(uint8_t addr, uint8_t reg, uint8_t *data, uint8_t len) {
+  if (I2C_MUTEX_LOCK()) {
+    
+    uint8_t ret = 0;
+    Wire.beginTransmission(addr);
+    Wire.write(reg);
+    for (uint16_t i = 0; i < len; i++) {
+      Wire.write(data[i]);
+    }
+    ret = Wire.endTransmission();
+
+    I2C_MUTEX_UNLOCK(); // release i2c bus access
+    return ret ? 0xFF : ret;
+    //return ret ? ret : 0xFF;
+  } else {
+    ESP_LOGW(TAG, "[%0.3f] i2c mutex lock failed", millis() / 1000.0);
+    return 0xFF;
+  }
+}
+
 #endif // HAS_PMU
 
 #ifdef BAT_MEASURE_ADC
@@ -196,12 +222,12 @@ uint16_t read_voltage() {
   uint16_t voltage = 0;
 
 #ifdef HAS_PMU
-  if (!I2C_MUTEX_LOCK())
+  //   if (!I2C_MUTEX_LOCK())
-    ESP_LOGW(TAG, "[%0.3f] i2c mutex lock failed", millis() / 1000.0);
+  //     ESP_LOGW(TAG, "[%0.3f] i2c mutex lock failed", millis() / 1000.0);
-  else {
+  //   else {
   voltage = pmu.isVBUSPlug() ? 0xffff : pmu.getBattVoltage();
-    I2C_MUTEX_UNLOCK();
+  //     I2C_MUTEX_UNLOCK();
-  }
+  //   }
 #else
 
 #ifdef BAT_MEASURE_ADC