// Copyright 2010-2016 Espressif Systems (Shanghai) PTE LTD
//
// 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 _DRIVER_SPI_MASTER_LOBO_H_
#define _DRIVER_SPI_MASTER_LOBO_H_

#include "esp_err.h"
#include "freertos/FreeRTOS.h"
#include "freertos/semphr.h"
#include "soc/spi_struct.h"

#include "esp_intr.h"
#include "esp_intr_alloc.h"
#include "rom/lldesc.h"


#ifdef __cplusplus
extern "C"
{
#endif


//Maximum amount of bytes that can be put in one DMA descriptor
#define SPI_MAX_DMA_LEN (4096-4)

/**
 * @brief Enum with the three SPI peripherals that are software-accessible in it
 */
typedef enum {
    TFT_SPI_HOST=0,                 ///< SPI1, SPI; Cannot be used in this driver!
    TFT_HSPI_HOST=1,                ///< SPI2, HSPI
    TFT_VSPI_HOST=2                 ///< SPI3, VSPI
} spi_lobo_host_device_t;


/**
 * @brief This is a configuration structure for a SPI bus.
 *
 * You can use this structure to specify the GPIO pins of the bus. Normally, the driver will use the
 * GPIO matrix to route the signals. An exception is made when all signals either can be routed through 
 * the IO_MUX or are -1. In that case, the IO_MUX is used, allowing for >40MHz speeds.
 */
typedef struct {
    int mosi_io_num;                ///< GPIO pin for Master Out Slave In (=spi_d) signal, or -1 if not used.
    int miso_io_num;                ///< GPIO pin for Master In Slave Out (=spi_q) signal, or -1 if not used.
    int sclk_io_num;                ///< GPIO pin for Spi CLocK signal, or -1 if not used.
    int quadwp_io_num;              ///< GPIO pin for WP (Write Protect) signal which is used as D2 in 4-bit communication modes, or -1 if not used.
    int quadhd_io_num;              ///< GPIO pin for HD (HolD) signal which is used as D3 in 4-bit communication modes, or -1 if not used.
    int max_transfer_sz;            ///< Maximum transfer size, in bytes. Defaults to 4094 if 0.
} spi_lobo_bus_config_t;


#define LB_SPI_DEVICE_TXBIT_LSBFIRST          (1<<0)  ///< Transmit command/address/data LSB first instead of the default MSB first
#define LB_SPI_DEVICE_RXBIT_LSBFIRST          (1<<1)  ///< Receive data LSB first instead of the default MSB first
#define LB_SPI_DEVICE_BIT_LSBFIRST            (SPI_TXBIT_LSBFIRST|SPI_RXBIT_LSBFIRST); ///< Transmit and receive LSB first
#define LB_SPI_DEVICE_3WIRE                   (1<<2)  ///< Use spiq for both sending and receiving data
#define LB_SPI_DEVICE_POSITIVE_CS             (1<<3)  ///< Make CS positive during a transaction instead of negative
#define LB_SPI_DEVICE_HALFDUPLEX              (1<<4)  ///< Transmit data before receiving it, instead of simultaneously
#define LB_SPI_DEVICE_CLK_AS_CS               (1<<5)  ///< Output clock on CS line if CS is active

#define SPI_ERR_OTHER_CONFIG 7001

typedef struct spi_lobo_transaction_t spi_lobo_transaction_t;
typedef void(*spi_lobo_transaction_cb_t)(spi_lobo_transaction_t *trans);

/**
 * @brief This is a configuration for a SPI slave device that is connected to one of the SPI buses.
 */
typedef struct {
    uint8_t command_bits;               ///< Amount of bits in command phase (0-16)
    uint8_t address_bits;               ///< Amount of bits in address phase (0-64)
    uint8_t dummy_bits;                 ///< Amount of dummy bits to insert between address and data phase
    uint8_t mode;                       ///< SPI mode (0-3)
    uint8_t duty_cycle_pos;             ///< Duty cycle of positive clock, in 1/256th increments (128 = 50%/50% duty). Setting this to 0 (=not setting it) is equivalent to setting this to 128.
    uint8_t cs_ena_pretrans;            ///< Amount of SPI bit-cycles the cs should be activated before the transmission (0-16). This only works on half-duplex transactions.
    uint8_t cs_ena_posttrans;           ///< Amount of SPI bit-cycles the cs should stay active after the transmission (0-16)
    int clock_speed_hz;                 ///< Clock speed, in Hz
    int spics_io_num;                   ///< CS GPIO pin for this device, handled by hardware; set to -1 if not used
    int spics_ext_io_num;               ///< CS GPIO pin for this device, handled by software (spi_lobo_device_select/spi_lobo_device_deselect); only used if spics_io_num=-1
    uint32_t flags;                     ///< Bitwise OR of LB_SPI_DEVICE_* flags
    spi_lobo_transaction_cb_t pre_cb;   ///< Callback to be called before a transmission is started. This callback from 'spi_lobo_transfer_data' function.
    spi_lobo_transaction_cb_t post_cb;  ///< Callback to be called after a transmission has completed. This callback from 'spi_lobo_transfer_data' function.
    uint8_t selected;                   ///< **INTERNAL** 1 if the device's CS pin is active
} spi_lobo_device_interface_config_t;


#define LB_SPI_TRANS_MODE_DIO            (1<<0)  ///< Transmit/receive data in 2-bit mode
#define LB_SPI_TRANS_MODE_QIO            (1<<1)  ///< Transmit/receive data in 4-bit mode
#define LB_SPI_TRANS_MODE_DIOQIO_ADDR    (1<<2)  ///< Also transmit address in mode selected by SPI_MODE_DIO/SPI_MODE_QIO
#define LB_SPI_TRANS_USE_RXDATA          (1<<3)  ///< Receive into rx_data member of spi_lobo_transaction_t instead into memory at rx_buffer.
#define LB_SPI_TRANS_USE_TXDATA          (1<<4)  ///< Transmit tx_data member of spi_lobo_transaction_t instead of data at tx_buffer. Do not set tx_buffer when using this.

/**
 * This structure describes one SPI transmission
 */
struct spi_lobo_transaction_t {
    uint32_t flags;                 ///< Bitwise OR of LB_SPI_TRANS_* flags
    uint16_t command;               ///< Command data. Specific length was given when device was added to the bus.
    uint64_t address;               ///< Address. Specific length was given when device was added to the bus.
    size_t length;                  ///< Total data length to be transmitted to the device, in bits; if 0, no data is transmitted
    size_t rxlength;                ///< Total data length to be received from the device, in bits; if 0, no data is received
    void *user;                     ///< User-defined variable. Can be used to store eg transaction ID or data to be used by pre_cb and/or post_cb callbacks.
    union {
        const void *tx_buffer;      ///< Pointer to transmit buffer, or NULL for no MOSI phase
        uint8_t tx_data[4];         ///< If SPI_USE_TXDATA is set, data set here is sent directly from this variable.
    };
    union {
        void *rx_buffer;            ///< Pointer to receive buffer, or NULL for no MISO phase
        uint8_t rx_data[4];         ///< If SPI_USE_RXDATA is set, data is received directly to this variable
    };
};

#define NO_CS 3					    // Number of CS pins per SPI host
#define NO_DEV 6				    // Number of spi devices per SPI host; more than 3 devices can be attached to the same bus if using software CS's
#define SPI_SEMAPHORE_WAIT 2000     // Time in ms to wait for SPI mutex

typedef struct spi_lobo_device_t spi_lobo_device_t;

typedef struct {
    spi_lobo_device_t *device[NO_DEV];
    intr_handle_t intr;
    spi_dev_t *hw;
    //spi_lobo_transaction_t *cur_trans;
    int cur_device;
    lldesc_t *dmadesc_tx;
    lldesc_t *dmadesc_rx;
    bool no_gpio_matrix;
    int dma_chan;
    int max_transfer_sz;
    QueueHandle_t spi_lobo_bus_mutex;
    spi_lobo_bus_config_t cur_bus_config;
} spi_lobo_host_t;

struct spi_lobo_device_t {
    spi_lobo_device_interface_config_t cfg;
    spi_lobo_host_t *host;
    spi_lobo_bus_config_t bus_config;
	spi_lobo_host_device_t host_dev;
};

typedef spi_lobo_device_t* spi_lobo_device_handle_t;  ///< Handle for a device on a SPI bus
typedef spi_lobo_host_t* spi_lobo_host_handle_t;
typedef spi_lobo_device_interface_config_t* spi_lobo_device_interface_config_handle_t;


/**
 * @brief Add a device. This allocates a CS line for the device, allocates memory for the device structure and hooks
 *        up the CS pin to whatever is specified.
 *
 * This initializes the internal structures for a device, plus allocates a CS pin on the indicated SPI master
 * peripheral and routes it to the indicated GPIO. All SPI master devices have three hw CS pins and can thus control
 * up to three devices. Software handled CS pin can also be used for additional devices on the same SPI bus.
 * 
 * ### If selected SPI host device bus is not yet initialized, it is initialized first with 'bus_config' function ###
 *
 * @note While in general, speeds up to 80MHz on the dedicated SPI pins and 40MHz on GPIO-matrix-routed pins are
 *       supported, full-duplex transfers routed over the GPIO matrix only support speeds up to 26MHz.
 *
 * @param host SPI peripheral to allocate device on (HSPI or VSPI)
 * @param dev_config SPI interface protocol config for the device
 * @param bus_config Pointer to a spi_lobo_bus_config_t struct specifying how the host device bus should be initialized
 * @param handle Pointer to variable to hold the device handle
 * @return
 *         - ESP_ERR_INVALID_ARG   if parameter is invalid
 *         - ESP_ERR_NOT_FOUND     if host doesn't have any free CS slots
 *         - ESP_ERR_NO_MEM        if out of memory
 *         - ESP_OK                on success
 */
esp_err_t spi_lobo_bus_add_device(spi_lobo_host_device_t host, spi_lobo_bus_config_t *bus_config, spi_lobo_device_interface_config_t *dev_config, spi_lobo_device_handle_t *handle);

/**
 * @brief Remove a device from the SPI bus. If after removal no other device is attached to the spi bus device, it is freed.
 *
 * @param handle Device handle to free
 * @return
 *         - ESP_ERR_INVALID_ARG   if parameter is invalid
 *         - ESP_ERR_INVALID_STATE if device already is freed
 *         - ESP_OK                on success
 */
esp_err_t spi_lobo_bus_remove_device(spi_lobo_device_handle_t handle);


/**
 * @brief Return the actuall SPI bus speed for the spi device in Hz
 *
 * Some frequencies cannot be set, for example 30000000 will actually set SPI clock to 26666666 Hz
 *
 * @param handle Device handle obtained using spi_lobo_bus_add_device
 * 
 * @return 
 *         - actuall SPI clock
 */
uint32_t spi_lobo_get_speed(spi_lobo_device_handle_t handle);

/**
 * @brief Set the new clock speed for the device, return the actuall SPI bus speed set, in Hz
 *        This function can be used after the device is initialized
 *
 * Some frequencies cannot be set, for example 30000000 will actually set SPI clock to 26666666 Hz
 *
 * @param handle Device handle obtained using spi_lobo_bus_add_device
 * @param speed  New device spi clock to be set in Hz
 * 
 * @return 
 *         - actuall SPI clock
 *         - 0 if speed cannot be set
 */
uint32_t spi_lobo_set_speed(spi_lobo_device_handle_t handle, uint32_t speed);

/**
 * @brief Select spi device for transmission
 *
 * It configures spi bus with selected spi device parameters if previously selected device was different than the current
 * If device's spics_io_num=-1 and spics_ext_io_num > 0 'spics_ext_io_num' pin is set to active state (low)
 * 
 * spi bus device's semaphore is taken before selecting the device
 *
 * @param handle Device handle obtained using spi_lobo_bus_add_device
 * @param force  configure spi bus even if the previous device was the same
 * 
 * @return 
 *         - ESP_ERR_INVALID_ARG   if parameter is invalid
 *         - ESP_OK                on success
 */
esp_err_t spi_lobo_device_select(spi_lobo_device_handle_t handle, int force);

/**
 * @brief De-select spi device
 *
 * If device's spics_io_num=-1 and spics_ext_io_num > 0 'spics_ext_io_num' pin is set to inactive state (high)
 * 
 * spi bus device's semaphore is given after selecting the device
 * 
 * @param handle Device handle obtained using spi_lobo_bus_add_device
 * 
 * @return 
 *         - ESP_ERR_INVALID_ARG   if parameter is invalid
 *         - ESP_OK                on success
 */
esp_err_t spi_lobo_device_deselect(spi_lobo_device_handle_t handle);


/**
 * @brief Check if spi bus uses native spi pins
 *
 * @param handle Device handle obtained using spi_lobo_bus_add_device
 * 
 * @return 
 *         - true        if native spi pins are used
 *         - false       if spi pins are routed through gpio matrix
 */
bool spi_lobo_uses_native_pins(spi_lobo_device_handle_t handle);

/**
 * @brief Get spi bus native spi pins
 *
 * @param handle Device handle obtained using spi_lobo_bus_add_device
 * 
 * @return 
 *         places spi bus native pins in provided pointers
 */
void spi_lobo_get_native_pins(int host, int *sdi, int *sdo, int *sck);

/**
 * @brief Transimit and receive data to/from spi device based on transaction data
 * 
 * TRANSMIT 8-bit data to spi device from 'trans->tx_buffer' or 'trans->tx_data' (trans->lenght/8 bytes)
 * and RECEIVE data to 'trans->rx_buffer' or 'trans->rx_data' (trans->rx_length/8 bytes)
 * Lengths must be 8-bit multiples!
 * If trans->rx_buffer is NULL or trans->rx_length is 0, only transmits data
 * If trans->tx_buffer is NULL or trans->length is 0, only receives data
 * If the device is in duplex mode (LB_SPI_DEVICE_HALFDUPLEX flag NOT set), data are transmitted and received simultaneously.
 * If the device is in half duplex mode (LB_SPI_DEVICE_HALFDUPLEX flag IS set), data are received after transmission
 * 'address', 'command' and 'dummy bits' are transmitted before data phase IF set in device's configuration
 *   and IF 'trans->length' and 'trans->rx_length' are NOT both 0
 * If device was not previously selected, it will be selected before transmission and deselected after transmission.
 *
 * @param handle Device handle obtained using spi_lobo_bus_add_device
 * 
 * @param trans Pointer to variable containing the description of the transaction that is executed
 *
 * @return
 *         - ESP_ERR_INVALID_ARG   if parameter is invalid
 *         - ESP error code        if device cannot be selected
 *         - ESP_OK                on success
 *
 */
esp_err_t spi_lobo_transfer_data(spi_lobo_device_handle_t handle, spi_lobo_transaction_t *trans);


/*
 * SPI transactions uses the semaphore (taken in select function) to protect the transfer
 */
esp_err_t spi_lobo_device_TakeSemaphore(spi_lobo_device_handle_t handle);
void spi_lobo_device_GiveSemaphore(spi_lobo_device_handle_t handle);


/**
 * @brief Setup a DMA link chain
 *
 * This routine will set up a chain of linked DMA descriptors in the array pointed to by
 * ``dmadesc``. Enough DMA descriptors will be used to fit the buffer of ``len`` bytes in, and the
 * descriptors will point to the corresponding positions in ``buffer`` and linked together. The
 * end result is that feeding ``dmadesc[0]`` into DMA hardware results in the entirety ``len`` bytes
 * of ``data`` being read or written.
 *
 * @param dmadesc Pointer to array of DMA descriptors big enough to be able to convey ``len`` bytes
 * @param len Length of buffer
 * @param data Data buffer to use for DMA transfer
 * @param isrx True if data is to be written into ``data``, false if it's to be read from ``data``.
 */
void spi_lobo_setup_dma_desc_links(lldesc_t *dmadesc, int len, const uint8_t *data, bool isrx);

/**
 * @brief Check if a DMA reset is requested but has not completed yet
 *
 * @return True when a DMA reset is requested but hasn't completed yet. False otherwise.
 */
bool spi_lobo_dmaworkaround_reset_in_progress();


/**
 * @brief Mark a DMA channel as idle.
 *
 * A call to this function tells the workaround logic that this channel will
 * not be affected by a global SPI DMA reset.
 */
void spi_lobo_dmaworkaround_idle(int dmachan);

/**
 * @brief Mark a DMA channel as active.
 *
 * A call to this function tells the workaround logic that this channel will
 * be affected by a global SPI DMA reset, and a reset like that should not be attempted.
 */
void spi_lobo_dmaworkaround_transfer_active(int dmachan);


#ifdef __cplusplus
}
#endif

#endif
