Unfortunately, sampling the INA219 at a 2kHz rate is currently not feasible. The INA219 driver has a hardcoded configuration for 12-bit resolution, which corresponds to a 532ms sampling time. Additionally, the driver is not optimized for high-rate reading from user space.
Could you please explain the reason for requiring such high-speed current consumption measurement? Perhaps we can offer an alternative solution. If this high rate is essential, you may need to write your own driver for the INA219, optimized for high-rate reading and data transfer from kernel space.
Please also consider that the Dahlia board has many other I2C devices on the same I2C bus, such as the RTC, USB hub, PCI board (if inserted), DSI adapter (if installed), audio codec, EEPROM, and temperature sensor. Flooding the I2C bus with a large number of INA219 transactions may affect the performance of these other devices.