bus_priorities.h

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#pragma once

 
#include "fl/channels/bus.h"
#include "fl/stl/stdint.h"
 
// Platform CMSIS/Arduino headers may define SPI / UART / I2S as register
// pointer macros (e.g. Sam3X8E: `#define UART ((Uart*)0x400E0800U)`).
// Those macros expand inside qualified names like `Bus::SPI` below and
// produce a syntax error. bus.h itself uses push_macro/pop_macro around
// its enum definition; once bus.h pops the macros are restored. So we
// must apply the same guard locally here. See fl/channels/bus.h.
#pragma push_macro("UART")
#pragma push_macro("SPI")
#pragma push_macro("I2S")
#undef UART
#undef SPI
#undef I2S
 
namespace fl {

constexpr int default_bus_priority(Bus b, fl::u8 which) FL_NO_EXCEPT {
    // 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;
}
 
}  // namespace fl
 
#pragma pop_macro("I2S")
#pragma pop_macro("SPI")
#pragma pop_macro("UART")