RADDevice

RADDevice covers common embedded Linux device control surfaces:

• GpioPin for sysfs GPIO export, direction, edge, and value.
• I2CDevice for /dev/i2c-* with I2C_SLAVE ioctl.
• SPIDevice for /dev/spidev* with SPI ioctl configuration and transfers.
• PwmChannel for sysfs PWM period, duty, and enable.
• AdcChannel for IIO raw and scaled samples.
• Watchdog for /dev/watchdog* keepalive ioctl.
• Led for sysfs LED brightness.

The public API is intentionally file-descriptor and ioctl friendly so future RADKernel drivers can expose the same application-facing model.