Add CONFIG_LLCC68_MAX_PAYLOAD_LENGTH with a default of 128 bytes and a hardware-bounded range of 1..255.
Wire both the C++ and raw C LLCC68 payload buffer constants to the Kconfig value so application builds can tune radio buffer RAM without editing headers.
Rename the fixed-length 100k preset from GMSK to GFSK and expose rx_bandwidth_hz() next to the GfskRxBandwidth enum so applications can report configured bandwidth without carrying driver-specific lookup tables.
Use a longer preamble and 32-bit detector for the 100 kbps fixed 6-byte GMSK profile.
Read RX payloads from the RxStartBufferPointer returned by GetRxBufferStatus. The previous subtract-by-length adjustment could read the previous FIFO slot once the continuous RX buffer advanced, causing duplicate and missing packet IDs on the gateway.
Rename the application-owned LLCC68 devicetree compatible to semtech,llcc68-weihua so Zephyr releases with a native semtech,llcc68 binding can coexist with this custom driver module.
Use the registered semtech vendor prefix and a project-specific device suffix; DT_DRV_COMPAT maps to semtech_llcc68_weihua.
Change the fixed 6-byte GMSK helper default to 434.18 MHz so new GMSK traffic does not share the existing 433.10, 433.45, and 433.90 MHz LoRa channels.
Add a fixed 6-byte 100 kbps GMSK profile matching the health-band telemetry packet, plus FSK packet-status helpers for RSSI and error checks. Expose instantaneous RSSI reads for CCA and image calibration for 430-440 MHz GFSK bring-up.
crosstyan