I believe you have got an error in the following register bit defines:
define INA219_CONFIG_BADCRES_9BIT (0x0080) // 9-bit bus res = 0..511
#define INA219_CONFIG_BADCRES_10BIT (0x0100) // 10-bit bus res = 0..1023
#define INA219_CONFIG_BADCRES_11BIT (0x0200) // 11-bit bus res = 0..2047
According to the datasheet, 9 bit resolution needs to be 0x0000. 10 bit should be 0x0080 and 11 bit should be 0x0100. The value you define for 11 bit (0x0200) actually selects 9 bit resolution.
I believe you have got an error in the following register bit defines:
define INA219_CONFIG_BADCRES_9BIT (0x0080) // 9-bit bus res = 0..511
According to the datasheet, 9 bit resolution needs to be 0x0000. 10 bit should be 0x0080 and 11 bit should be 0x0100. The value you define for 11 bit (0x0200) actually selects 9 bit resolution.