mbed-os/features/nfc/nfc/NFCEEPROMDriver.h

/* mbed Microcontroller Library
 * Copyright (c) 2018 ARM Limited
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef MBED_NFC_EEPROM_DRIVER_H
#define MBED_NFC_EEPROM_DRIVER_H

#include <stdint.h>

#include "events/EventQueue.h"

namespace mbed {
namespace nfc {

/**
 * @addtogroup nfc
 * @{
 */

/**
 * The abstraction for a NFC EEPROM driver.
 * Implementers need to derive from this class and implement its methods.
 */
class NFCEEPROMDriver  {
public:
    /**
     * Construct a NFCEEPROM driver instance.
     */
    NFCEEPROMDriver();

    /**
     * NFCEEPROM driver destructor.
     */
    virtual ~NFCEEPROMDriver();

    /**
     * The NFCEEPROMDriver delegate.
     * Methods in this class are called by the driver on completion of long-running operations.
     */
    struct Delegate {
        /**
         * Completion of session start operation.
         *
         * @param[in] success whether this operation succeeded
         */
        virtual void on_session_started(bool success) = 0;

        /**
         * Completion of session end operation.
         *
         * @param[in] success whether this operation succeeded
         */
        virtual void on_session_ended(bool success) = 0;

        /**
         * Completion of read operation.
         *
         * @param[in] count number of bytes actually read
         */
        virtual void on_bytes_read(size_t count) = 0;

        /**
         * Completion of write operation.
         *
         * @param[in] count number of bytes actually written
         */
        virtual void on_bytes_written(size_t count) = 0;

        /**
         * Completion of size retrieval operation.
         *
         * @param[in] success whether this operation succeeded
         * @param[out] size the current addressable memory size
         */
        virtual void on_size_read(bool success, size_t size) = 0;

        /**
         * Completion of size setting operation.
         *
         * @param[in] success whether this operation succeeded
         */
        virtual void on_size_written(bool success) = 0;

        /**
         * Completion of erasing operation.
         *
         * @param[in] count number of bytes actually erased
         */
        virtual void on_bytes_erased(size_t count) = 0;

    protected:
        ~Delegate() {}
    };

    /**
     * Set the delegate that will receive events generated by this EEPROM.
     *
     * @param[in] delegate the delegate instance to use
     */
    void set_delegate(Delegate *delegate);

    /**
     * Set the event queue that will be used to schedule event handling
     *
     * @param[in] queue the queue instance to use
     */
    void set_event_queue(events::EventQueue *queue);

    /**
     * Reset and initialize the EEPROM.
     * This method should complete synchronously.
     */
    virtual void reset() = 0;

    /**
     * Get the maximum memory size addressable by the EEPROM.
     */
    virtual size_t read_max_size() = 0;

    /**
     * Start a session of operations (reads, writes, erases, size gets/sets).
     * This method is called prior to any memory access to allow the underlying implementation
     * to disable the RF interface or abort the transaction if it's being used.
     * This method should complete asynchronously by calling has_started_session().
     */
    virtual void start_session(bool force = true) = 0; // This could lock the chip's RF interface

    /**
     * End a session.
     * This method should complete asynchronously by calling has_ended_session().
     */
    virtual void end_session() = 0;

    /**
     * Read bytes from memory.
     * @param[in] address the virtual address (starting from 0) from which to start the read.
     * @param[out] bytes a buffer in which the read bytes will be stored.
     *  This buffer should remain valid till the callback is called.
     * @param[in] count the number of bytes to read.
     * This method should complete asynchronously by calling has_read_bytes().
     */
    virtual void read_bytes(uint32_t address, uint8_t *bytes, size_t count) = 0;

    /**
     * Write bytes to memory.
     * @param[in] address the virtual address (starting from 0) from which to start the write.
     * @param[in] bytes a buffer from to copy.
     *  This buffer should remain valid till the callback is called.
     * @param[in] count the number of bytes to write.
     * This method should complete asynchronously by calling has_written_bytes().
     */
    virtual void write_bytes(uint32_t address, const uint8_t *bytes, size_t count) = 0;

    /**
     * Retrieve the size of the addressable memory.
     * This method should complete asynchronously by calling has_gotten_size().
     */
    virtual void read_size() = 0;

    /**
     * Set the size of the addressable memory.
     * @param[in] count the number of addressable bytes.
     * This method should complete asynchronously by calling has_set_size().
     */
    virtual void write_size(size_t count) = 0;

    /**
     * Erase bytes from memory.
     * @param[in] address the virtual address (starting from 0) from which to start erasing.
     * @param[in] size the number of bytes to erase.
     * This method should complete asynchronously by calling has_erased_bytes().
     */
    virtual void erase_bytes(uint32_t address, size_t size) = 0;

protected:
    Delegate *delegate();
    events::EventQueue *event_queue();

private:
    Delegate *_delegate;
    events::EventQueue *_event_queue;
};

/**
 * @}
 */

} // namespace nfc
} // namespace mbed

#endif