Snake in mux scan func and handler, not operational yet

Author: brentru

src/components/i2c/controller.cpp

@@ -587,7 +587,11 @@ bool I2cController::Handle_I2cBusScan(pb_istream_t *stream) {
     // TODO: Print out what was scanned? or do this at the end
   }
 
-  // TODO If Muxes are present, scan them
+  // Case 3: Do we have a MUX on the default bus?
+  if (_i2c_model->GetI2cBusScanMsg()->i2c_mux_descriptors_count > 0) {
+    // Iterate through the MUX descriptors, scanning each MUX
+  }
+
   // TODO Scan I2C Port 1 for Muxes
   // TODO Scan I2C Port 2 for Muxes
 

src/components/i2c/hardware.cpp

@@ -151,6 +151,7 @@ bool I2cHardware::ScanBus(wippersnapper_i2c_I2cBusScanned *scan_results) {
       #endif */
 
   // Get the SDA and SCL pins from the bus
+  // TODO: Abstract this?
   char i2c_bus_scl[15] = {0}, i2c_bus_sda[15] = {0};
   snprintf(i2c_bus_scl, sizeof(i2c_bus_scl), "D%u", _bus_scl);
   snprintf(i2c_bus_sda, sizeof(i2c_bus_sda), "D%u", _bus_sda);
@@ -165,6 +166,7 @@ bool I2cHardware::ScanBus(wippersnapper_i2c_I2cBusScanned *scan_results) {
 
     if (endTransmissionRC == 0) {
       WS_DEBUG_PRINTLN("[i2c] Found Device!");
+      // TODO: Abstract this? Allow for mux flags to be set here, too
       scan_results
           ->i2c_bus_found_devices[scan_results->i2c_bus_found_devices_count]
           .i2c_device_address = address;
@@ -292,4 +294,21 @@ void I2cHardware::SelectMuxChannel(uint32_t channel) {
     @returns  True if a MUX is present on the bus, False otherwise.
 */
 /***********************************************************************/
-bool I2cHardware::HasMux() { return _has_mux; }
+bool I2cHardware::HasMux() { return _has_mux; }
+
+bool I2cHardware::ScanMux(wippersnapper_i2c_I2cBusScanned* scan_results) {
+    if (!HasMux()) {
+      WS_DEBUG_PRINTLN("[i2c] ERROR: No MUX present on the bus!");
+      return false;
+    }
+
+    for (uint8_t ch = 0; ch < _mux_max_channels; ch++) {
+      SelectMuxChannel(ch);
+      WS_DEBUG_PRINT("[i2c] Scanning MUX Channel: ");
+      WS_DEBUG_PRINTLN(ch);
+      if (!ScanBus(scan_results)) {
+        WS_DEBUG_PRINTLN("[i2c] ERROR: Failed to scan MUX channel!");
+        return false;
+      }
+    }
+}

src/components/i2c/hardware.h

@@ -43,6 +43,7 @@ class I2cHardware {
   void SelectMuxChannel(uint32_t channel);
   bool HasMux();
   void ClearMuxChannel();
+  bool ScanMux(wippersnapper_i2c_I2cBusScanned* scan_results);
 private:
   void TogglePowerPin();
   wippersnapper_i2c_I2cBusStatus _bus_status; ///< I2C bus status