default_bus_priority()

int fl::default_bus_priority ( Bus b, fl::u8 which )

constexpr

Default priority assigned to a Bus when registered with the manager.

Higher = preferred. The function is constexpr so callers can use it in constant expressions if needed. Buses without a registered priority fall back to 0.

Definition at line 38 of file bus_priorities.h.

                                                                   {
    // FORCE-style overrides (FASTLED_ESP32_FORCE_*) are intentionally not
    // applied here -- the legacy initChannelDrivers() retains its own
    // priority-bumping logic for backward compatibility. This table is the
    // baseline used by the new enableDrivers<>() opt-in API.
    //
    // Secondary FLEX_IO instances sit one below the primary so the
    // manager fills the primary bank first and overflows to the
    // secondary (classic-ESP32 I2S0 second bank, ESP32-P4 LCD_RGB —
    // FastLED#3576 Phase 1).
    return
        b == Bus::FLEX_IO   ? (which == 0 ? 4 : which == 1 ? 3 : 2) :
        b == Bus::RMT       ? 2  :
        b == Bus::SPI       ? 1  :
        b == Bus::DUAL_SPI  ? 1  :
        b == Bus::QUAD_SPI  ? 1  :
        b == Bus::OCTAL_SPI ? 1  :
        b == Bus::BIT_BANG  ? 0  :
        b == Bus::UART      ? (which == 0 ? -1 : -2) :
        0;
}

References BIT_BANG, DUAL_SPI, FL_NO_EXCEPT, FLEX_IO, OCTAL_SPI, QUAD_SPI, RMT, SPI, and UART.