fix(taranis): restore volume cli for I2C audio targets (#6543)

radio/src/cli.cpp

@@ -1497,6 +1497,11 @@ int cliDisplay(const char ** argv)
     gettime(&utm);
     cliSerialPrint("rtc = %4d-%02d-%02d %02d:%02d:%02d.%02d0", utm.tm_year+TM_YEAR_BASE, utm.tm_mon+1, utm.tm_mday, utm.tm_hour, utm.tm_min, utm.tm_sec, g_ms100);
   }
+#if defined(VOLUME_I2C_ADDRESS)
+  else if (!strcmp(argv[1], "volume")) {
+    cliSerialPrint("volume = %d", getVolume());
+  }
+#endif
   else if (!strcmp(argv[1], "uid")) {
     char str[LEN_CPU_UID+1];
     getCPUUniqueID(str);

radio/src/targets/taranis/hal.h

@@ -883,6 +883,9 @@
 #if !defined(SOFTWARE_VOLUME)
   #define VOLUME_I2C_ADDRESS            0x2E
   #define VOLUME_I2C_BUS                I2C_Bus_1
+
+  #include <stdint.h>
+  int32_t getVolume();
 #endif
 
 #define I2C_B1_CLK_RATE                 400000

radio/src/targets/taranis/volume_i2c.cpp

@@ -57,4 +57,9 @@ void audioSetVolume(uint8_t volume)
   write_i2c_volume(volumeScale[volume]);
 }
 
+int32_t getVolume()
+{
+  return read_i2c_volume();
+}
+
 #endif