/*! @file Driver.c

  @brief
  @author  Hendrik Schutter
  @version V1.0
  @date    03.11.2020


*/

#include "Driver.h"

//Place data into DRAM. Constant data gets placed into DROM by default, which is not accessible by DMA.
DRAM_ATTR static const lcd_init_cmd_t st_init_cmds[]= {
    /* Memory Data Access Control, MX=MV=1, MY=ML=MH=0, RGB=0 */
    {0x36, {(1<<5)|(1<<6)}, 1},
    /* Interface Pixel Format, 16bits/pixel for RGB/MCU interface */
    {0x3A, {0x55}, 1},
    /* Porch Setting */
    {0xB2, {0x0c, 0x0c, 0x00, 0x33, 0x33}, 5},
    /* Gate Control, Vgh=13.65V, Vgl=-10.43V */
    {0xB7, {0x45}, 1},
    /* VCOM Setting, VCOM=1.175V */
    {0xBB, {0x2B}, 1},
    /* LCM Control, XOR: BGR, MX, MH */
    {0xC0, {0x2C}, 1},
    /* VDV and VRH Command Enable, enable=1 */
    {0xC2, {0x01, 0xff}, 2},
    /* VRH Set, Vap=4.4+... */
    {0xC3, {0x11}, 1},
    /* VDV Set, VDV=0 */
    {0xC4, {0x20}, 1},
    /* Frame Rate Control, 60Hz, inversion=0 */
    {0xC6, {0x0f}, 1},
    /* Power Control 1, AVDD=6.8V, AVCL=-4.8V, VDDS=2.3V */
    {0xD0, {0xA4, 0xA1}, 1},
    /* Positive Voltage Gamma Control */
    {0xE0, {0xD0, 0x00, 0x05, 0x0E, 0x15, 0x0D, 0x37, 0x43, 0x47, 0x09, 0x15, 0x12, 0x16, 0x19}, 14},
    /* Negative Voltage Gamma Control */
    {0xE1, {0xD0, 0x00, 0x05, 0x0D, 0x0C, 0x06, 0x2D, 0x44, 0x40, 0x0E, 0x1C, 0x18, 0x16, 0x19}, 14},
    /* Sleep Out */
    {0x11, {0}, 0x80},
    /* Display On */
    {0x29, {0}, 0x80},
    {0, {0}, 0xff}
};

DRAM_ATTR static const lcd_init_cmd_t ili_init_cmds[]= {
    /* Power contorl B, power control = 0, DC_ENA = 1 */
    {0xCF, {0x00, 0x83, 0X30}, 3},
    /* Power on sequence control,
     * cp1 keeps 1 frame, 1st frame enable
     * vcl = 0, ddvdh=3, vgh=1, vgl=2
     * DDVDH_ENH=1
     */
    {0xED, {0x64, 0x03, 0X12, 0X81}, 4},
    /* Driver timing control A,
     * non-overlap=default +1
     * EQ=default - 1, CR=default
     * pre-charge=default - 1
     */
    {0xE8, {0x85, 0x01, 0x79}, 3},
    /* Power control A, Vcore=1.6V, DDVDH=5.6V */
    {0xCB, {0x39, 0x2C, 0x00, 0x34, 0x02}, 5},
    /* Pump ratio control, DDVDH=2xVCl */
    {0xF7, {0x20}, 1},
    /* Driver timing control, all=0 unit */
    {0xEA, {0x00, 0x00}, 2},
    /* Power control 1, GVDD=4.75V */
    {0xC0, {0x26}, 1},
    /* Power control 2, DDVDH=VCl*2, VGH=VCl*7, VGL=-VCl*3 */
    {0xC1, {0x11}, 1},
    /* VCOM control 1, VCOMH=4.025V, VCOML=-0.950V */
    {0xC5, {0x35, 0x3E}, 2},
    /* VCOM control 2, VCOMH=VMH-2, VCOML=VML-2 */
    {0xC7, {0xBE}, 1},
    /* Memory access contorl, MX=MY=0, MV=1, ML=0, BGR=1, MH=0 */
    {0x36, {0x28}, 1},
    /* Pixel format, 16bits/pixel for RGB/MCU interface */
    {0x3A, {0x55}, 1},
    /* Frame rate control, f=fosc, 70Hz fps */
    {0xB1, {0x00, 0x1B}, 2},
    /* Enable 3G, disabled */
    {0xF2, {0x08}, 1},
    /* Gamma set, curve 1 */
    {0x26, {0x01}, 1},
    /* Positive gamma correction */
    {0xE0, {0x1F, 0x1A, 0x18, 0x0A, 0x0F, 0x06, 0x45, 0X87, 0x32, 0x0A, 0x07, 0x02, 0x07, 0x05, 0x00}, 15},
    /* Negative gamma correction */
    {0XE1, {0x00, 0x25, 0x27, 0x05, 0x10, 0x09, 0x3A, 0x78, 0x4D, 0x05, 0x18, 0x0D, 0x38, 0x3A, 0x1F}, 15},
    /* Column address set, SC=0, EC=0xEF */
    {0x2A, {0x00, 0x00, 0x00, 0xEF}, 4},
    /* Page address set, SP=0, EP=0x013F */
    {0x2B, {0x00, 0x00, 0x01, 0x3f}, 4},
    /* Memory write */
    {0x2C, {0}, 0},
    /* Entry mode set, Low vol detect disabled, normal display */
    {0xB7, {0x07}, 1},
    /* Display function control */
    {0xB6, {0x0A, 0x82, 0x27, 0x00}, 4},
    /* Sleep out */
    {0x11, {0}, 0x80},
    /* Display on */
    {0x29, {0}, 0x80},
    {0, {0}, 0xff},
};



/* Send a command to the LCD. Uses spi_device_polling_transmit, which waits
 * until the transfer is complete.
 *
 * Since command transactions are usually small, they are handled in polling
 * mode for higher speed. The overhead of interrupt transactions is more than
 * just waiting for the transaction to complete.
 */
void vDriver_cmd(spi_device_handle_t spi, const uint8_t cmd)
{
    esp_err_t ret;
    spi_transaction_t t;
    memset(&t, 0, sizeof(t));       //Zero out the transaction
    t.length=8;                     //Command is 8 bits
    t.tx_buffer=&cmd;               //The data is the cmd itself
    t.user=(void*)0;                //D/C needs to be set to 0
    ret=spi_device_polling_transmit(spi, &t);  //Transmit!
    assert(ret==ESP_OK);            //Should have had no issues.
}

/* Send data to the LCD. Uses spi_device_polling_transmit, which waits until the
 * transfer is complete.
 *
 * Since data transactions are usually small, they are handled in polling
 * mode for higher speed. The overhead of interrupt transactions is more than
 * just waiting for the transaction to complete.
 */
void vDriver_data(spi_device_handle_t spi, const uint8_t *data, int len)
{
    esp_err_t ret;
    spi_transaction_t t;
    if (len==0) return;             //no need to send anything
    memset(&t, 0, sizeof(t));       //Zero out the transaction
    t.length=len*8;                 //Len is in bytes, transaction length is in bits.
    t.tx_buffer=data;               //Data
    t.user=(void*)1;                //D/C needs to be set to 1
    ret=spi_device_polling_transmit(spi, &t);  //Transmit!
    assert(ret==ESP_OK);            //Should have had no issues.
}

//This function is called (in irq context!) just before a transmission starts. It will
//set the D/C line to the value indicated in the user field.
void vDriver_spi_pre_transfer_callback(spi_transaction_t *t)
{
    int dc=(int)t->user;
    gpio_set_level(PIN_NUM_DC, dc);
}

uint32_t vDriver_get_id(spi_device_handle_t spi)
{
    //get_id cmd
    vDriver_cmd(spi, 0x04);

    spi_transaction_t t;
    memset(&t, 0, sizeof(t));
    t.length=8*3;
    t.flags = SPI_TRANS_USE_RXDATA;
    t.user = (void*)1;

    esp_err_t ret = spi_device_polling_transmit(spi, &t);
    assert( ret == ESP_OK );

    return *(uint32_t*)t.rx_data;
}

//Initialize the display
void vDriver_init(spi_device_handle_t spi)
{
    int cmd=0;
    const lcd_init_cmd_t* lcd_init_cmds;

    //Initialize non-SPI GPIOs
    gpio_set_direction(PIN_NUM_DC, GPIO_MODE_OUTPUT);
    gpio_set_direction(PIN_NUM_RST, GPIO_MODE_OUTPUT);
    gpio_set_direction(PIN_NUM_BCKL, GPIO_MODE_OUTPUT);

    //Reset the display
    gpio_set_level(PIN_NUM_RST, 0);
    vTaskDelay(100 / portTICK_RATE_MS);
    gpio_set_level(PIN_NUM_RST, 1);
    vTaskDelay(100 / portTICK_RATE_MS);

    //detect LCD type
    uint32_t lcd_id = vDriver_get_id(spi);
    int lcd_detected_type = 0;
    int lcd_type;

    printf("LCD ID: %08X\n", lcd_id);
    if ( lcd_id == 0 ) {
        //zero, ili
        lcd_detected_type = LCD_TYPE_ILI;
        printf("ILI9341 detected.\n");
    } else {
        // none-zero, ST
        lcd_detected_type = LCD_TYPE_ST;
        printf("ST7789V detected.\n");
    }

#ifdef CONFIG_LCD_TYPE_AUTO
    lcd_type = lcd_detected_type;
#elif defined( CONFIG_LCD_TYPE_ST7789V )
    printf("kconfig: force CONFIG_LCD_TYPE_ST7789V.\n");
    lcd_type = LCD_TYPE_ST;
#elif defined( CONFIG_LCD_TYPE_ILI9341 )
    printf("kconfig: force CONFIG_LCD_TYPE_ILI9341.\n");
    lcd_type = LCD_TYPE_ILI;
#endif
    if ( lcd_type == LCD_TYPE_ST ) {
        printf("LCD ST7789V initialization.\n");
        lcd_init_cmds = st_init_cmds;
    } else {
        printf("LCD ILI9341 initialization.\n");
        lcd_init_cmds = ili_init_cmds;
    }

    //Send all the commands
    while (lcd_init_cmds[cmd].databytes!=0xff) {
        vDriver_cmd(spi, lcd_init_cmds[cmd].cmd);
        vDriver_data(spi, lcd_init_cmds[cmd].data, lcd_init_cmds[cmd].databytes&0x1F);
        if (lcd_init_cmds[cmd].databytes&0x80) {
            vTaskDelay(100 / portTICK_RATE_MS);
        }
        cmd++;
    }

    ///Enable backlight
    gpio_set_level(PIN_NUM_BCKL, 0);
}