Class ChannelEngineSpi

src/platforms/esp/32/drivers/spi/channel_driver_spi.h:188–519

@brief Clockless-over-SPI IChannelDriver implementation ⚠️ This is a CLOCKLESS LED driver using SPI hardware, NOT a true SPI chipset driver! Consolidates clockless LED strip functionality using SPI peripheral as bit-banger: - Implements clockless protocols (WS2812, SK6812, etc.) via SPI bit patterns - Direct ESP-IDF SPI master driver integration - Wave8 encoding (SPI clock from chipset timing, 8

///
/// Managed by ChannelManager which handles frame lifecycle events.
class ChannelEngineSpi : public IChannelDriver {
public:
    ChannelEngineSpi() FL_NOEXCEPT;
    ~ChannelEngineSpi() override;

    /// @brief Configure multi-lane SPI pins for a specific data pin
    /// @param pinConfig Multi-lane pin configuration
    ///
    /// Example usage:
    /// @code
    /// // Dual-lane SPI (2x throughput)
    /// driver.configureMultiLanePins(MultiLanePinConfig(23, 19));
    ///
    /// // Quad-lane SPI (4x throughput, ESP32/S2/S3 only)
    /// driver.configureMultiLanePins(MultiLanePinConfig(23, 19, 18, 5));
    /// @endcode
    void configureMultiLanePins(const MultiLanePinConfig& pinConfig) FL_NOEXCEPT;

    // IChannelDriver interface implementation
    void enqueue(ChannelDataPtr channelData) FL_NOEXCEPT override;
    void show() FL_NOEXCEPT override;
    DriverState poll() FL_NOEXCEPT override;

    /// @brief Get the driver name for affinity binding
    /// @return "SPI"
    fl::string getName() const FL_NOEXCEPT override { return fl::string::from_literal("SPI"); }

    /// @brief Get driver capabilities (CLOCKLESS protocols only)
    /// @return Capabilities with supportsClockless=true, supportsSpi=false
    /// @note This is a clockless-over-SPI driver, not a true SPI LED driver
    Capabilities getCapabilities() const FL_NOEXCEPT override {
        return Capabilities(true, false);  // Clockless only
    }

    /// @brief Check if this driver can handle the given channel data
    /// @param data Channel data to check
    /// @return true for CLOCKLESS chipsets (WS2812, SK6812, etc.), false for true SPI chipsets
    ///
    /// This driver is a CLOCKLESS-over-SPI driver:
    ///   - Returns true for clockless protocols (WS2812, SK6812, etc.)
    ///   - Returns false for true SPI protocols (APA102, SK9822, etc.)
    bool canHandle(const ChannelDataPtr& data) const FL_NOEXCEPT override;

private:
    /// @brief Begin LED data transmission with internal batching (internal helper)
    /// @param channelData Span of channel data to transmit
    ///
    /// Groups channels by timing compatibility and batches them when N > K,
    /// where N = number of channels with compatible timings and K = available lanes.
    void beginBatchedTransmission(fl::span<const ChannelDataPtr> channelData) FL_NOEXCEPT;

    /// @brief Begin LED data transmission for all channels (internal helper)
    /// @param channelData Span of channel data to transmit
    void beginTransmission(fl::span<const ChannelDataPtr> channelData) FL_NOEXCEPT;

    /// @brief Determine maximum parallel transmission capacity
    /// @param channels Channels in a timing group (unused, for future extension)
    /// @return Number of SPI hosts available (2 for ESP32/S2/S3/P4, 1 for ESP32-C3)