CLSH1001-Firmware/managed_components/espressif__esp-idf-cxx/include/spi_host_cxx.hpp
2024-03-05 16:09:49 -06:00

415 lines
15 KiB
C++

/*
* SPDX-FileCopyrightText: 2021 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#pragma once
#if __cpp_exceptions
#include <exception>
#include <memory>
#include <chrono>
#include <vector>
#include <list>
#include <future>
#include "system_cxx.hpp"
#include "spi_cxx.hpp"
namespace idf {
/**
* @brief Exception which is thrown in the context of SPI Transactions.
*/
struct SPITransferException : public SPIException {
SPITransferException(esp_err_t error);
};
class SPIDevice;
class SPIDeviceHandle;
/**
* @brief Describes and encapsulates the transaction.
*
* @note This class is intended to be used internally by the SPI C++ classes, but not publicly.
* Furthermore, currently only one transaction per time can be handled. If you need to
* send several transactions in parallel, you need to build your own mechanism around a
* FreeRTOS task and a queue.
*/
class SPITransactionDescriptor {
friend class SPIDeviceHandle;
public:
/**
* @brief Create a SPITransactionDescriptor object, describing a full duplex transaction.
*
* @param data_to_send The data sent to the SPI device. It can be dummy data if a read-only
* transaction is intended. Its length determines the length of both write and read operation.
* @param handle to the internal driver handle
* @param pre_callback If non-empty, this callback will be called directly before the transaction.
* @param post_callback If non-empty, this callback will be called directly after the transaction.
* @param user_data optional data which will be accessible in the callbacks declared above
*/
SPITransactionDescriptor(const std::vector<uint8_t> &data_to_send,
SPIDeviceHandle *handle,
std::function<void(void *)> pre_callback = nullptr,
std::function<void(void *)> post_callback = nullptr,
void* user_data = nullptr);
/**
* @brief Deinitialize and delete all data of the transaction.
*
* @note This destructor must not becalled before the transaction is finished by the driver.
*/
~SPITransactionDescriptor();
SPITransactionDescriptor(const SPITransactionDescriptor&) = delete;
SPITransactionDescriptor operator=(const SPITransactionDescriptor&) = delete;
/**
* @brief Queue the transaction asynchronously.
*/
void start();
/**
* @brief Synchronously (blocking) wait for the result and return the result data or throw an exception.
*
* @return The data read from the SPI device. Its length is the length of \c data_to_send passed in the
* constructor.
* @throws SPIException in case of an error of the underlying driver or if the driver returns a wrong
* transaction descriptor for some reason. In the former case, the error code is the one from the
* underlying driver, in the latter case, the error code is ESP_ERR_INVALID_STATE.
*/
std::vector<uint8_t> get();
/**
* @brief Wait until the asynchronous operation is done.
*
* @throws SPIException in case of an error of the underlying driver or if the driver returns a wrong
* transaction descriptor for some reason. In the former case, the error code is the one from the
* underlying driver, in the latter case, the error code is ESP_ERR_INVALID_STATE.
*/
void wait();
/**
* @brief Wait for a result of the transaction up to timeout ms.
*
* @param timeout Maximum timeout value for waiting
*
* @return true if result is available, false if wait timed out
*
* @throws SPIException in case of an error of the underlying driver or if the driver returns a wrong
* transaction descriptor for some reason. In the former case, the error code is the one from the
* underlying driver, in the latter case, the error code is ESP_ERR_INVALID_STATE.
*/
bool wait_for(const std::chrono::milliseconds &timeout);
private:
/**
* Private descriptor data.
*/
void *private_transaction_desc;
/**
* Private device data.
*/
SPIDeviceHandle *device_handle;
/**
* @brief If non-empty, this callback will be called directly before the transaction.
*/
std::function<void(void *)> pre_callback;
/**
* @brief If non-empty, this callback will be called directly after the transaction.
*/
std::function<void(void *)> post_callback;
/**
* Buffer in spi_transaction_t is const, so we have to declare it here because we want to
* allocate and delete it.
*/
uint8_t *tx_buffer;
/**
* @brief User data which will be provided in the callbacks.
*/
void *user_data;
/**
* Tells if data has been received, i.e. the transaction has finished and the result can be acquired.
*/
bool received_data;
/**
* Tells if the transaction has been initiated and is at least in-flight, if not finished.
*/
bool started;
};
/**
* @brief SPIFuture for asynchronous transaction results, mostly equivalent to std::future.
*
* This re-implementation is necessary as std::future is incompatible with the IDF SPI driver interface.
*/
class SPIFuture {
public:
/**
* @brief Create an invalid future.
*/
SPIFuture();
/**
* @brief Create a valid future with \c transaction as shared state.
*
* @param transaction the shared transaction state
*/
SPIFuture(std::shared_ptr<SPITransactionDescriptor> transaction);
SPIFuture(const SPIFuture &other) = delete;
/**
* @brief Move constructor as in std::future, leaves \c other invalid.
*
* @param other object to move from, will become invalid during this constructor
*/
SPIFuture(SPIFuture &&other) noexcept;
/**
* @brief Move assignment as in std::future, leaves \c other invalid.
*
* @param other object to move from, will become invalid during this constructor
* @return A reference to the newly created SPIFuture object
*/
SPIFuture &operator=(SPIFuture&& other) noexcept;
/**
* @brief Wait until the asynchronous operation is done and return the result or throw and exception.
*
* @throws std::future_error if this future is not valid.
* @throws SPIException in case of an error of the underlying driver or if the driver returns a wrong
* transaction descriptor for some reason. In the former case, the error code is the one from the
* underlying driver, in the latter case, the error code is ESP_ERR_INVALID_STATE.
* @return The result of the asynchronous SPI transaction.
*/
std::vector<uint8_t> get();
/**
* @brief Wait for a result up to timeout ms.
*
* @param timeout Maximum timeout value for waiting
*
* @return std::future_status::ready if result is available, std::future_status::timeout if wait timed out
*/
std::future_status wait_for(std::chrono::milliseconds timeout);
/**
* @brief Wait for a result indefinitely.
*/
void wait();
/**
* @return true if this future is valid, otherwise false.
*/
bool valid() const noexcept;
private:
/**
* The SPITransactionDescriptor, which is the shared state of this future.
*/
std::shared_ptr<SPITransactionDescriptor> transaction;
/**
* Indicates if this future is valid.
*/
bool is_valid;
};
/**
* @brief Represents an device on an initialized Master Bus.
*/
class SPIDevice {
public:
/**
* @brief Create and initialize a device on the master bus corresponding to spi_host.
*
* @param cs The pin number of the chip select signal for the device to create.
* @param spi_host the spi_host (bus) to which the device shall be attached.
* @param frequency The devices frequency. this frequency will be set during transactions to the device which will be
* created.
* @param transaction_queue_size The of the transaction queue of this device. This determines how many
* transactions can be queued at the same time. Currently, it is set to 1 since the
* implementation exclusively acquires the bus for each transaction. This may change in the future.
*/
SPIDevice(SPINum spi_host,
CS cs,
Frequency frequency = Frequency::MHz(1),
QueueSize transaction_queue_size = QueueSize(1u));
SPIDevice(const SPIDevice&) = delete;
SPIDevice operator=(const SPIDevice&) = delete;
/**
* @brief De-initializes and destroys the device.
*
* @warning Behavior is undefined if a device is destroyed while there is still an ongoing transaction
* from that device.
*/
~SPIDevice();
/**
* @brief Queue a transfer to this device.
*
* This method creates a full-duplex transfer to the device represented by the current instance of this class.
* It then queues that transfer and returns a "future" object. The future object will become ready once
* the transfer finishes.
*
* @param data_to_send Data which will be sent to the device. The length of the data determines the length
* of the full-deplex transfer. I.e., the same amount of bytes will be received from the device.
* @param pre_callback If non-empty, this callback will be called directly before the transaction.
* If empty, it will be ignored.
* @param post_callback If non-empty, this callback will be called directly after the transaction.
* If empty, it will be ignored.
* @param user_data This pointer will be sent to pre_callback and/or pre_callback, if any of them is non-empty.
*
* @return a future object which will become ready once the transfer has finished. See also \c SPIFuture.
*/
SPIFuture transfer(const std::vector<uint8_t> &data_to_send,
std::function<void(void *)> pre_callback = nullptr,
std::function<void(void *)> post_callback = nullptr,
void* user_data = nullptr);
/**
* @brief Queue a transfer to this device like \c transfer, but using begin/end iterators instead of a
* data vector.
*
* This method is equivalent to \c transfer(), except for the parameters.
*
* @param begin Iterator to the begin of the data which will be sent to the device.
* @param end Iterator to the end of the data which will be sent to the device.
* This iterator determines the length of the data and hence the length of the full-deplex transfer.
* I.e., the same amount of bytes will be received from the device.
* @param pre_callback If non-empty, this callback will be called directly before the transaction.
* If empty, it will be ignored.
* @param post_callback If non-empty, this callback will be called directly after the transaction.
* If empty, it will be ignored.
* @param user_data This pointer will be sent to pre_callback and/or pre_callback, if any of them is non-empty.
*
* @return a future object which will become ready once the transfer has finished. See also \c SPIFuture.
*/
template<typename IteratorT>
SPIFuture transfer(IteratorT begin,
IteratorT end,
std::function<void(void *)> pre_callback = nullptr,
std::function<void(void *)> post_callback = nullptr,
void* user_data = nullptr);
private:
/**
* Private device data.
*/
SPIDeviceHandle *device_handle;
/**
* Saves the current transaction descriptor in case the user's loses its future with the other
* reference to the transaction.
*/
std::shared_ptr<SPITransactionDescriptor> current_transaction;
};
/**
* @brief Represents an SPI Master Bus.
*/
class SPIMaster {
public:
/*
* @brief Create an SPI Master Bus.
*
* @param host The SPI host (bus) which should be used. ESP chips have a number of different possible SPI hosts,
* each of which will create its own bus. Consult the datasheet and TRM on which host to choose.
* @param mosi The pin number for the MOSI signal of this bus.
* @param miso The pin number for the MISO signal of this bus.
* @param sclk The pin number for the clock signal of this bus.
* @param dma_config The DMA configuration for this bus, see \c DMAConfig.
* @param max_transfer_size The maximum transfer size in bytes.
*
* @throws SPIException with IDF error code if the underlying driver fails.
*/
explicit SPIMaster(SPINum host,
const MOSI &mosi,
const MISO &miso,
const SCLK &sclk,
SPI_DMAConfig dma_config = SPI_DMAConfig::AUTO(),
SPITransferSize max_transfer_size = SPITransferSize::default_size());
/*
* @brief Create an SPI Master Bus.
*
* @param host The SPI host (bus) which should be used. ESP chips have a number of different possible SPI hosts,
* each of which will create its own bus. Consult the datasheet and TRM on which host to choose.
* @param mosi The pin number for the MOSI signal of this bus.
* @param miso The pin number for the MISO signal of this bus.
* @param sclk The pin number for the clock signal of this bus.
* @param qspiwp The pin number for the QSPIWP signal of this bus.
* @param qspihd The pin number for the QSPIHD signal of this bus.
* @param dma_config The DMA configuration for this bus, see \c DMAConfig.
* @param max_transfer_size The maximum transfer size in bytes.
*
* @throws SPIException with IDF error code if the underlying driver fails.
*/
explicit SPIMaster(SPINum host,
const MOSI &mosi,
const MISO &miso,
const SCLK &sclk,
const QSPIWP &qspiwp,
const QSPIHD &qspihd,
SPI_DMAConfig dma_config = SPI_DMAConfig::AUTO(),
SPITransferSize max_transfer_size = SPITransferSize::default_size());
SPIMaster(const SPIMaster&) = delete;
SPIMaster operator=(const SPIMaster&) = delete;
SPIMaster(SPIMaster&&) = default;
SPIMaster &operator=(SPIMaster&&) = default;
/*
* @brief De-initializes and destroys the SPI Master Bus.
*
* @note Devices created before which try to initialize an exception after the bus is destroyed will throw
* and exception.
*/
virtual ~SPIMaster();
/**
* @brief Create a representation of a device on this bus.
*
* @param cs The pin number for the CS (chip select) signal to talk to the device.
* @param f The frequency used to talk to the device.
*/
std::shared_ptr<SPIDevice> create_dev(CS cs, Frequency frequency = Frequency::MHz(1));
private:
/**
* @brief Host identifier for internal use.
*/
SPINum spi_host;
};
template<typename IteratorT>
SPIFuture SPIDevice::transfer(IteratorT begin,
IteratorT end,
std::function<void(void *)> pre_callback,
std::function<void(void *)> post_callback,
void* user_data)
{
std::vector<uint8_t> write_data;
write_data.assign(begin, end);
return transfer(write_data, pre_callback, post_callback, user_data);
}
}
#endif