MI PSPI API

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REVISION HISTORY

Revision No.	Description	Date
1.00	Initial release	25/09/2020
2.00	Improve the overview description	18/04/2025

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1. Overview

1.1. Module Description

PSPI is based on the SPI communication protocol and is designed to achieve communication between Sensor and Panel.

When PSPI is used as a Slave, it can communicate with the Sensor. Vsync is the indication signal from the Sensor to PSPI, indicating that the Sensor is ready to send a frame of image, and its valid signal is high level.

When PSPI is used as a Master, it can communicate with the Panel. Te is the indication signal from the Panel to PSPI, indicating that the Panel has started to refresh all internal buffers to the display, and its valid signal is high level.

1.2. Basic structure

PSPI is not currently connected to other MI modules, and its functions are mainly implemented through the development of the application layer.

When the hardware is connected to the Pannel, the initialization of the Pannel is implemented by the application layer calling the function MI_PSPI_Transfer() to pass in the screen parameters, and then the application layer continuously passes the image data to the PSPI Master;

When the hardware is connected to the Sensor, the initialization of the Sensor is implemented by the application layer calling the function MI_PSPI_Enable(), which will trigger the init flow that has been set for the sensor, and then obtain the sensor data through the PSPI Slave.

1.3. Functional introduction

• Support polarity and phase configuration of SPI clock (SCLK)

• Support polarity switching of chip select (SS) signal

• Single transmission word length can be selected from 3 to 32 bits

• Allow chip select (SS) signal to remain valid between word transmissions

• Support FIFO mode and DMA mode

• Support dual-channel/quad-channel mode reading and writing in DMA mode through BDMA

• Support single-channel/dual-channel writing of RGB565 and BRG565 in DMA mode

• Support reception of TE signal and VSYNC signal

• Support skipping TE signal times, the times can be selected from 0 to 15

• Support polarity switching of TE signal

1.4. Application scenarios

PSPI can be applied to the following scenarios:

1. Pure Linux scenario

Develop based on the API interface provided by PSPI in the Linux environment

1.5. Chip differences

The differences between PSPI on different chips are mainly reflected in the different PAD MODE settings affecting different communication functions. In the following list, 1 indicates support, and 0 indicates unsupport.

The chip described in this document is pcupid.

1.5.1. Ikayaki

CHIP	PAD MODE	MODE INDEX	3wire mode	4wire mode	dual mod	equal mod	master tx	master rx	slave tx	slave rx
Ikayaki	reg_pspi0_g_mode	mode 1	1	0	0	0	1	1	1	1
		mode 2	1	0	1	1	1	1	1	1
	reg_pspi0_sr_mode	mode 1	1	0	1	1	1	0	0	1
		mode 2	1	0	1	1	1	0	0	1
		mode 3	1	0	1	0	1	0	0	1
		mode 4	1	0	1	0	1	0	0	1
		mode 5	1	0	0	0	1	0	0	1
		mode 6	1	0	0	0	1	0	0	1
	reg_pspi1_g_mode	mode 1	1	0	0	0	1	1	1	1
		mode 2	1	0	1	1	1	1	1	1
	reg_pspi1_pl_mode	mode 1	1	0	1	0	1	0	0	1
		mode 2	1	0	1	0	1	0	0	1
		mode 3	1	0	1	0	1	0	0	1
		mode 4	1	0	1	0	1	0	0	1
		mode 5	1	0	1	0	1	0	0	1
		mode 6	1	0	0	0	1	0	0	1

1.5.2. Opera

CHIP	PAD MODE	MODE INDEX	3wire mode	4wire mode	dual mod	equal mod	master tx	master rx	slave tx	slave rx
Opera	reg_pspi0_g_mode	mode 1	1	0	1	1	1	1	1	1
	reg_pspi0_sensor_mode	mode 1	1	0	1	0	1	0	0	1
		mode 2	1	0	1	1	1	0	0	1
		mode 3	1	0	0	0	1	0	0	1
	reg_pspi1_g_mode	mode 1	1	0	1	1	1	1	1	1
	reg_pspi0_pannel_mode	mode 1	1	0	1	0	1	0	0	1
		mode 2	1	0	1	0	1	0	0	1

1.5.3. Pcupid

CHIP	PAD MODE	MODE INDEX	3wire mode	4wire mode	dual mod	equal mod	master tx	master rx	slave tx	slave rx
Pcupid	reg_pspi0_g_mode	mode 1	1	1	1	1	1	1	1	1
	reg_pspi0_mode	mode 1	1	0	1	1	1	0	1	1
		mode 2	1	0	1	1	1	0	1	1
		mode 3	1	0	1	0	1	0	1	1
		mode 4	1	0	1	0	1	0	1	1
		mode 5	1	0	0	0	1	0	1	1
	reg_pspi1_g_mode	mode 1	1	1	1	1	1	1	1	1
	reg_pspi1_mode	mode 1	1	0	1	0	1	0	1	1
		mode 2	1	0	1	0	1	0	1	1
		mode 3	1	1	0	0	1	1	1	1
		mode 4	1	0	1	1	1	0	1	1
		mode 5	1	0	1	1	1	1	1	0

1.6. Working Principle

PSPI is based on the SPI communication protocol, so it has all the SPI communication features. It is essentially data transmission and reception, so only the special communication mode of PSPI is described.

1.6.1. TE Mode

Generally, Pannel can dynamically start and stop the synchronization signal by operating the TE Line On/Off command. PSPI can receive TE signals for signal synchronization to prevent screen tearing.

In addition, PSPI supports skipping 0~15 TE signals so that PSPI can be delayed when the TE signal is triggered.

For example: if the number of skips is set to 2, each time PSPI receives a TE signal, the following two TE signals will be skipped.

1.6.2. Quad/Dual Mode Read Data Format

PSPI supports bit order reversal in Quad Mode/Dual Mode

Quad Mode regular read is as follows:

Quad Mode bit order reversal read is as follows:

Dual Mode regular read is as follows:

Dual Mode bit order reversal read is as follows:

1.7. Development Process

1.7.1. Compile Configuration

Compile KO

Select defconfig, enter the project directory, make menuconfig and open MI_PSPI

Sdk Config-->
    [*] Interface Compile Config -->
        [*] pspi -->
            [*] nhal_pspi
            [*] mi_pspi
            (bf3901.ko gc032a.ko) PSPIDEV List
            (bf3901.ko) PSPIDEV0
            (pspi_id=1 pspi_slave=0x6e) PSPIDEV0 Opt

After compiling and successfully burning, the module mi_pspi.ko and pspi device will be automatically loaded at booting.

PSPIDEV List: Select pspi device, the source code is located in the sdk/driver/PspiDriver/drv directory, for example, the bf301 sensor. The source code is named drv_pspi_bf3901.c, after adding to the List, it will compile and generate bf3901.ko.

PSPIDEV0: Select the pspi device module that will be automatically insmoded after successful burning and startup. According to the above content, after startup, the program will first insmod mi_pspi.ko and then insmod drv_pspi_bf3901.ko.

PSPIDEV0 Opt: Select the input parameters when insmod device ko, pspi_id=1 means to bind bf3901 to pspi bus1, pspi_slave=0x6e means to fill in the slave address of this sensor = 0x6e.

Custom KO

Add files to the directory sdk/driver/PspiDriver/drv, and the naming method is fixed to drv_pspi_xxx.ko, where xxx is the device model. You can refer to drv_pspi_bf3901.c and complete the two parts of the structure information xxx_liner and PSPI_SENSOR_InitTable.

bf3901_linear describes pixel array and fps of sensor

static struct {
    struct _senout{
        s32 width, height, min_fps, max_fps;
    }senout;

    struct _senstr{
        const char* strResDesc;
    }senstr;

}bf3901_linear[] = {
    { {240, 320, 0, 30}, {"240x320@30fps"}},
};

PSPI_SENSOR_InitTable fills in the sensor initialization command in the format of registers and values. If a delay is required after setting a register, the value can be filled in as 0xffff

const static IIC_ARRAY_t PSPI_SENSOR_InitTable[] =
{
    {0x12, 0x80},
    {0x11, 0xb0},
    {0x1b, 0x80},
    {0x6b, 0x01},
    {0x12, 0x20},
    {0x3a, 0x00},
    ......
    {0x13, 0x05},
    {0x6a, 0x81},
    {0x23, 0x00},
    {0x01, 0x08},
    {0x02, 0x08},
};

1.7.2. PADMUX Configuration

Take PSPI0 connecting to Sensor as an example：

Enter directorykernel/driver/arch/arm64/boot/dts/sstar/chipname-xxx-padmux.dtsi，Configured PSPI0 as MODE1

<PAD_OUTP_RX0_CH0        PINMUX_FOR_PSPI0_MODE_1          MDRV_PUSE_PSPI1_CS>,
<PAD_OUTN_RX0_CH0        PINMUX_FOR_PSPI0_MODE_1          MDRV_PUSE_PSPI1_VSYNC>,
<PAD_OUTP_RX0_CH1        PINMUX_FOR_PSPI0_MODE_1          MDRV_PUSE_PSPI1_CLK>,
<PAD_OUTN_RX0_CH1        PINMUX_FOR_PSPI0_MODE_1          MDRV_PUSE_PSPI1_MISO0>,
<PAD_OUTP_RX0_CH2        PINMUX_FOR_PSPI0_MODE_1          MDRV_PUSE_PSPI1_MISO1>,
<PAD_OUTN_RX0_CH2        PINMUX_FOR_PSPI0_MODE_1          MDRV_PUSE_PSPI1_MISO2>,
<PAD_OUTP_RX0_CH3        PINMUX_FOR_PSPI0_MODE_1          MDRV_PUSE_PSPI1_MISO3>,
<PAD_GPIOB_02            PINMUX_FOR_SR00_MCLK_MODE_2      MDRV_PUSE_SR00_MCLK>,

Take PSPI1 connecting to Pannel as an example：

Enter directorykernel/driver/arch/arm64/boot/dts/sstar/chipname-xxx-padmux.dtsi，Configured PSPI1 as MODE1

<PAD_GPIOA_12                PINMUX_FOR_PSPI1_MODE_1      MDRV_PUSE_PSPI1_CS>,
<PAD_GPIOA_13                PINMUX_FOR_PSPI1_MODE_1      MDRV_PUSE_PSPI1_CLK>,
<PAD_GPIOA_14                PINMUX_FOR_PSPI1_MODE_1      MDRV_PUSE_PSPI1_MOSI0>,
<PAD_GPIOA_15                PINMUX_FOR_PSPI1_MODE_1      MDRV_PUSE_PSPI1_MOSI1>,
<PAD_GPIOA_16                PINMUX_FOR_PSPI1_TE_MODE_1   MDRV_PUSE_PSPI1_TE>,

1.7.3. Running Environment Description

Hardware Connection Notes

The PIN pins of PSPI1 MODE1 are all concentrated in JP114. Please make sure the wiring is correct.

Switch JP24 to 3.3V

UT Program Running Instructions

Ensure that mi_pspi.ko file is loaded when the board starts, transplant the prog_pspi, reset.sh and dev0_sensor_datalane2_auto.json files to the board, and enter the command to run the UT program:

prog_pspi -i dev0_sensor_datalane2_auto.json -t 50000

-i specifies the json file; -t specifies the program running time in milliseconds

The image data passed into the panel uses red, green and blue by default. If you want to change it, you can modify it in sdk/verify/mi_demo/source/pspi/ut_pspi_main.c:

1.8. Example introduction

1.8.1. Sensor routine

int main(int argc, char *argv[])
{
    int fd = 0
    MI_PSPI_DEV   pspi_dev = 0;
    MI_PSPI_Param_t  pspi_para;
    MI_PSPI_OutputAttr_t stOutputAttr;
    MI_SYS_ChnPort_t stChnPort;
    MI_SYS_BufInfo_t stBufInfo;
    MI_SYS_BUF_HANDLE hSysBuf;
    memset(&stChnPort, 0x0, sizeof(MI_SYS_ChnPort_t));
    memset(&stBufInfo, 0x0, sizeof(MI_SYS_BufInfo_t));
    memset(&hSysBuf, 0x0, sizeof(MI_SYS_BUF_HANDLE));
    memset(&pspi_para, 0x0, sizeof(MI_PSPI_SpiParam_t));
    stChnPort.eModId    = E_MI_MODULE_ID_PSPI;
    stChnPort.u32DevId  = 0;
    stChnPort.u32ChnId  = 0;
    stChnPort.u32PortId = 0;
    stOutputAttr.u16Width   = 1920;
    stOutputAttr.u16Width   = 1080;
    stOutputAttr.ePixelFormat = E_MI_SYS_PIXEL_FRAME_YUV_SEMIPLANAR_420;
    pspi_para.u8BitsPerWord   = 8;
    pspi_para.u8DataLane      = DATA_DUAL;
    pspi_para.u16DelayCycle   = 0;
    pspi_para.u16WaitCycle    = 0;
    pspi_para.u8RgbSwap       = 0;
    pspi_para.u32MaxSpeedHz   = 1000000;
    pspi_para.u16PspiMode     = SPI_SLAVE;
    pspi_para.u8ChipSelect    = MI_PSPI_SELECT_0;
    pspi_para.ePspiType       =  E_MI_PSPI_TYPE_RX;
    pspi_para.eTriggerMode    = E_MI_PSPI_TRIGGER_MODE_AUTO;
    /***
    Send commands to sensor by IIC
    ***/
    MI_SYS_Init();
    MI_PSPI_CreateDevice(pspi_dev, &pspi_para);
    MI_PSPI_SetOutputAttr(&stOutputAttr);
    MI_PSPI_Enable(pspi_dev);
    MI_SYS_SetChnOutputPortDepth(&stChnPort,3,4);
GET_OUT_BUF:
    if (MI_SUCCESS != MI_SYS_ChnOutputPortGetBuf(&stChnPort, &stBufInfo, &hSysBuf))
    {
        goto GET_OUT_BUF;
    }
    fd = open(“picture”, O_RDWR|O_CREAT|O_TRUNC, 0777);
    write(fd, tBufInfo.stFrameData.pVirAddr[0], stBufInfo.stFrameData.u32BufSize));
    sync();
    close(fd);
PUT_OUT_BUF:
    if (MI_SUCCESS != MI_SYS_ChnOutputPortPutBuf(hSysBuf))
    {
        goto PUT_OUT_BUF;
    }
    MI_SYS_SetChnOutputPortDepth(&stChnPort,0,3);
    MI_PSPI_Disable(pspi_dev);
    MI_PSPI_DestroyDevice(pspi_dev);
    MI_SYS_Exit();
    Return 0;
}

1.8.2. Panel routine

int main（int argc, char *argv[]）
{
    MI_S32 s32Ret = 0;
    MI_U16 * buff = NULL;
    MI_U32 size = 0;
    MI_PSPI_Msg_t  pspi_msg;
    MI_PSPI_Param_t  pspi_para;
    MI_PSPI_DEV   pspi_dev = 1;
    MI_SYS_ChnPort_t  stChnPort;
    MI_SYS_BUF_HANDLE  stHandle;
    MI_SYS_BufInfo_t   stBufInfo;s
    MI_SYS_BufConf_t  stBufConf;
    pspi_para.u8BitsPerWord    = 9;
    pspi_para.u8DataLane       = DATA_SINGLE;
    pspi_para.u16DelayCycle    = 2;
    pspi_para.u16WaitCycle     = 2;
    pspi_para.u8RgbSwap        = 0;
    pspi_para.u32MaxSpeedHz    = 1000000;
    pspi_para.u16PspiMode      = 0;
    pspi_para.u8ChipSelect     = MI_PSPI_SELECT_0;
    pspi_para.u8TeMode         = 0;
    MI_PSPI_CreateDevice(pspi_dev, &pspi_para);
    memset(&pspi_msg, 0 ,sizeof(MI_PSPI_Msg_t));
    pspi_msg.u8TxBitCount = 9;
    pspi_msg.u8RxBitCount = 8;
    pspi_msg.u8TxSize = 1;
    //0xDA
    pspi_msg.au16TxBuf[0] = 0xDA;
    MI_PSPI_Transfer(pspi_dev,  & pspi_msg);
    /****    Send commands to the panel   *****/
    memset(&stChnPort, 0, sizeof(MI_SYS_ChnPort_t));
    memset(&stBufConf, 0, sizeof(MI_SYS_BufConf_t));
    memset(&stBufInfo, 0, sizeof(MI_SYS_BufInfo_t));
    memset(&stHandle, 0, sizeof(MI_SYS_BUF_HANDLE));
    stChnPort.eModId = E_MI_MODULE_ID_PSPI;
    stChnPort.u32DevId = 1;
    stChnPort.u32ChnId = 0;
    stChnPort.u32PortId = 0;
    stBufConf.eBufType = E_MI_SYS_BUFDATA_FRAME;
    stBufConf.stFrameCfg.u16Height = 240;
    stBufConf.stFrameCfg.u16Width  = 320;
    stBufConf.stFrameCfg.eFrameScanMode = E_MI_SYS_FRAME_SCAN_MODE_PROGRESSIVE;
    stBufConf.stFrameCfg.eFormat    = E_MI_SYS_PIXEL_FRAME_RGB565;
    MI_PSPI_Enable(pspi_dev);
    while(1)
    {
        getBuff1:
        if (MI_SYS_ChnInputPortGetBuf(&stChnPort,&stBufConf,&stBufInfo,&stHandle,4000)!= MI_SUCCESS)
        {
            printf("get input port buf red failed\n");
            goto getBuff1;
        }
        else
        {
            printf("MI_SYS_ChnInputPortGetBuf success 1\n");
            buff =  (MI_U16 *)stBufInfo.stFrameData.pVirAddr[0];
            size = stBufInfo.stFrameData.u32BufSize/2;
            for(i = 0; i < size ; i++)
            {
                buff[i] = 0xf800;
            }
        putbuff1:
            if(MI_SYS_ChnInputPortPutBuf(stHandle, &stBufInfo, FALSE) != MI_SUCCESS)
            {
                printf("writter frame err 1\n");
                goto putbuff1;
            }
            else
                printf("written a frame red to screen success\n");
        }
    }
}

2. API Reference

2.1. API List

API name	Features
MI_PSPI_CreateDevice	Create PSPI and configure PSPI properties
MI_PSPI_DestroyDevice	Destroy PSPI
MI_PSPI_Transfer	Send parameter information to PSPI, and configure the parameters of externally connected devices
MI_PSPI_SetDevAttr	Set PSPI properties
MI_PSPI_SetOutputAttr	Set PSPI output port properties
MI_PSPI_Enable	Enable PSPI
MI_PSPI_Disable	Disable PSPI

2.2. MI_PSPI_CreateDevice

• Features

  Create PSPI and configure PSPI properties.

• Syntax

  MI_S32 MI_PSPI_CreateDevice (MI_PSPI_DEV PspiDev, MI_PSPI_Param_t *pstPspiParam);
  

• Parameter

  Parameter Name	Description	Input/Output
  PspiDev	PSPI specific devices	Input
  pstPspiParam	Specific properties of PSPI devices	Input

• Return value

  • MI_PSPI_SUCCESS: Successful.

  • Not MI_PSPI_SUCCESS: Failed, refer to Error code.

• Requirement

  • Header: mi_pspi.h, mi_pspi_datatype.h

  • Library: libmi_pspi.a / libmi_pspi.so

• Note

  The same PSPI device can’t be created twice in a row. If necessary, you can modify the properties of PSPI through MI_PSPI_SetDevAttr.

2.3. MI_PSPI_DestroyDevice

• Features

  Destroy PSPI.

• Syntax

  MI_S32 MI_PSPI_DestroyDevice(MI_PSPI_DEV PspiDev);
  

• Parameter

  Parameter Name	Description	Input/Output
  PspiDev	PSPI device that needs to be destroyed.	Input

• Return value

  • MI_PSPI_SUCCESS: Successful.

  • Not MI_PSPI_SUCCESS: Failed, refer to Error code.

• Requirement

  • Header: mi_pspi.h, mi_pspi_datatype.h

  • Library: libmi_pspi.a / libmi_pspi.so

2.4. MI_PSPI_Transfer

• Features

  Send parameter information to PSPI, and configure the parameters of externally connected devices.

• Syntax

  MI_S32 MI_PSPI_Transfer(MI_PSPI_DEV PspiDev, MI_PSPI_Msg_t *pstMsg);
  

• Parameter

  Parameter Name	Description	Input/Output
  PspiDev	PSPI specific devices	Input
  pstMsg	Specific parameters sent to the slave device	Input

• Return value

  • MI_PSPI_SUCCESS: Successful.

  • Not MI_PSPI_SUCCESS: Failed, refer to Error code.

• Requirement

  • Header: mi_pspi.h, mi_pspi_datatype.h

  • Library: libmi_pspi.a / libmi_pspi.so

• Note

  • The function sends data to the slave through PSPI to control the slave, For example, when using PSPI to light up the panel, you need to send some control parameters to the panel before sending specific image data, and these control parameters can be sent through this function. The number of parameters sent at one time can be controlled by the PSPI_PARAM_BUFF_SIZE macro in mi_pspi_datatype.h.

2.5. MI_PSPI_SetDevAttr

• Features

  Set PSPI properties.

• Syntax

  MI_S32 MI_PSPI_SetDevAttr(MI_PSPI_DEV PspiDev, MI_PSPI_Param_t * pstPspiParam);
  

• Parameter

  Parameter Name	Description	Input/Output
  PspiDev	PSPI specific devices	Input
  pstPspiParam	Specific properties to be configured	Input

• Return value

  • MI_PSPI_SUCCESS: Successful.

  • Not MI_PSPI_SUCCESS: Failed, refer to Error code.

• Requirement

  • Header: mi_pspi.h, mi_pspi_datatype.h

  • Library: libmi_pspi.a / libmi_pspi.so

• Note

  • It is used to modify the properties of PSPI. Ignore it if not used.

2.6. MI_PSPI_SetOutputAttr

• Features

  Set PSPI output port properties.

• Syntax

  MI_S32 MI_PSPI_SetOutputAttr(MI_PSPI_OutputAttr_t * pstOutputAttr);
  

• Parameter

  Parameter Name	Description	Input/Output
  pstOutputAttr	Properties to be configured	Input

• Return value

  • MI_PSPI_SUCCESS: Successful.

  • Not MI_PSPI_SUCCESS: Failed, refer to Error code.

• Requirement

  • Header: mi_pspi.h, mi_pspi_datatype.h

  • Library: libmi_pspi.a / libmi_pspi.so

• Note

  • It is used to set the buffer attribute for storing sensor data. The function is useless when connecting to the panel. The default attribute of the sensor output channel is 640 * 480, YUV 422 format.

2.7. MI_PSPI_Enable

• Features

  Enable PSPI device.

• Syntax

  MI_S32 MI_PSPI_Enable(MI_PSPI_DEV PspiDev);
  

• Parameter

  Parameter Name	Description	Input/Output
  PspiDev	PSPI device to be enabled	Input

• Return value

  • MI_PSPI_SUCCESS: Successful.

  • Not MI_PSPI_SUCCESS: Failed, refer to Error code.

• Requirement

  • Header: mi_pspi.h, mi_pspi_datatype.h

  • Library: libmi_pspi.a / libmi_pspi.so

• Note

  • Before using the mi_sys related interface to operate PSPI, you must call this function to enable.

2.8. MI_PSPI_Disable

• Features

  Disable PSPI.

• Syntax

  MI_S32 MI_PSPI_Disable(MI_PSPI_DEV PspiDev);
  

• Parameter

  Parameter Name	Description	Input/Output
  PspiDev	PSPI device to be disabled	Input

• Return value

  • MI_PSPI_SUCCESS: Successful.

  • Not MI_PSPI_SUCCESS: Failed, refer to Error code.

• Requirement

  • Header: mi_pspi.h, mi_pspi_datatype.h

  • Library: libmi_pspi.a / libmi_pspi.so

• Note

  • When PSPI is not used, this function must be called to disenable it.

3. PSPI Data Type

3.1. PSPI data type list

The PSPI module related data types are defined as follows:

DATA TYPE	Description
MI_PSPI_Msg_t	Define the data frame of the PSPI device parameters transmitted to the external connection.
MI_PSPI_OutputAttr_t	Define PSPI output port properties.
MI_PSPI_Param_t	Define PSPI properties.
MI_PSPI_TriggerMode_e	Define PSPI Trigger mode.
MI_PSPI_Type_e	Define PSPI device type.
MI_PSPI_DEV	Define PSPI device number.

3.2. MI_PSPI_Msg_t

• Description

  Define the data frame of the PSPI device parameters transmitted to the external connection.

• Definition

  typedef struct MI_PSPI_Msg_s
  {
      MI_U16 u16TxSize;
      MI_U16 u16RxSize;
      MI_U8  u8TxBitCount;
      MI_U8  u8RxBitCount;
      MI_U16 au16TxBuf[PSPI_PARAM_BUFF_SIZE];
      MI_U16 au16RxBuf[PSPI_PARAM_BUFF_SIZE];
  } MI_PSPI_Msg_t;
  

• Note

  • The maximum number of data transmitted each time is controlled by the macro PSPI_PARAM_BUFF_SIZE.

• Member

  Member name	Description
  u16TxSize	Number of sent data (MI_U16typesize)
  u16RxSize	Number of received data (MI_U16 type size)
  u8TxBitCount	The number of bits transmitted at one time when sending
  u8RxBitCount	The number of bits transmitted at one time when receiving
  au16TxBuf[PSPI_PARAM_BUFF_SIZE]	Send data buffer
  au16RxBuf[PSPI_PARAM_BUFF_SIZE]	Receive data buffer

• Related data types and interfaces

  MI_PSPI_Transfer

3.3. MI_PSPI_OutputAttr_t

• Description

  Define PSPI output port properties. It is used to describe the properties of the connected sensor, because PSPI has an output port only when it is connected to sensor.

• Definition

  typedef struct MI_PSPI_OutputAttr_s
  {
      MI_SYS_PixelFormat_e ePixelFormat;
      MI_U16               u16Width;
      MI_U16               u16Height;
  } MI_PSPI_OutputAttr_t;
  

• Member

  Member name	Description
  ePixelFormat	Define the format of sensor input data
  u16Width	Define the width of the sensor input image data
  u16Height	Define the height of sensor input image data

• Related data types and interfaces

  MI_PSPI_SetOutputAttr

3.4. MI_PSPI_Param_t

• Description

  Define PSPI properties.

• Definition

  typedef struct MI_PSPI_Param_s
  {
      MI_U32                u32MaxSpeedHz;
      MI_U16                u16DelayCycle; // cs is inactive
      MI_U16                u16WaitCycle;  // cs is active
      MI_U16                u16PspiMode;
      MI_U8                 u8DataLane;    // cs count
      MI_U8                 u8BitsPerWord; // The number of bitsin an SPI transmission
      MI_U8                 u8RgbSwap;     // for panel
      MI_U8                 u8TeMode;      // for panel
      MI_U8                 u8ChipSelect;
      MI_PSPI_Type_e        ePspiType;
      MI_PSPI_TriggerMode_e eTriggerMode;  // select trigger mode
  } MI_PSPI_Param_t;
  

• Member

  Member name	Description	Optional value
  u32MaxSpeedHz	Max clock frequency	1000000~54000000
  u16DelayCycle	When SPI_SSCTL is not set, the delay between two data transmissions	0x0000~0xFFFF, the unit is clock cycle
  u16WaitCycle	When SPI_SSCTL is set, the delay between two data transmissions	0x0000~0xFFFF, the unit is clock cycle
  u16PspiMode	PSPI mode configuration	0: Host mode, MSB, receiving on rising edge, sending on falling edge. The chip select signal is active at low level, and the chip select signal is active during two data transfers. SPI_CPHA: sending on rising edge, receiving on falling edge. SPI_CPOL: sending on rising edge, receiving on falling edge. SPI_CPHA|SPI_CPOL: receiving on rising edge, sending on falling edge. SPI_SLAVE: PSPI as a slave. SPI_LSB: PSPI LSB first. SPI_SSPOL: Chip select signal polarity control, high level is effective when set. SPI_SSCTL: Controls whether the chip select signal remains valid between two data transmissions by PSPI. If set, the chip select signal is invalid during two data transfers.
  u8DataLane	Number of data lines when sending	DATA_SINGLE: Single line DATA_DUAL: Double line DATA_QUAD: Quadra line
  u8BitsPerWord	Number of bits sent each time	Can be configured from 3 to 32
  u8RgbSwap	The format and the number of data lines when sending data to the panel	RGB_SINGLE: RGB format, single line RGB_DUAL: RGB format, double line BGR_SINGLE：BGR format, single line BGR_DUAL: BGR format, double line Note: Need to configure data_lane synchronously
  u8TeMode	Whether to use TE mode	1: Y; 0: N
  u8ChipSelect	PSPI chip select signal	MI_PSPI_SELECT_0; MI_PSPI_SELECT_1
  ePspiType	PSPI device type	TX or RX
  eTriggerMode	PSPI trigger mode	Auto trigger or Auto+Vsync trigger

• Related data types and interfaces

  MI_PSPI_CreateDevice

  MI_PSPI_SetDevAttr

3.5. MI_PSPI_TriggerMode_e

• Description

  Define PSPI trigger mode.

• Definition

  typedef enum
  {
      E_MI_PSPI_TRIGGER_MODE_NA = 0,
      E_MI_PSPI_TRIGGER_MODE_AUTO,
      E_MI_PSPI_TRIGGER_MODE_AUTO_VSYNC,
      E_MI_PSPI_TRIGGER_MODE_MAX,
  } MI_PSPI_TriggerMode_e;
  

• Note

  1. If user selects Auto+Vsync trigger mode, the pspi sensor dev must have Vsync trigger bus.
  2. If user selects Auto trigger mode, the first two frames of data will be lost.
  3. Select Auto trigger mode by default.

• Related data types and interfaces

  MI_PSPI_CreateDevice

  MI_PSPI_SetDevAttr

3.6. MI_PSPI_Type_e

• Description

  Define PSPI dev type. exp：Uesr should use RX to receive data from sensor; use TX to transfor data to panel.

• Definition

  typedef enum
  {
      E_MI_PSPI_INVALID_TYPE = 0,
      E_MI_PSPI_TYPE_RX      = 1,
      E_MI_PSPI_TYPE_TX      = 2,
      E_MI_PSPI_TYPE_MAX,
  } MI_PSPI_Type_e;
  

• Note

  Select RX by defualt.

• Related data types and interfaces

  MI_PSPI_CreateDevice

  MI_PSPI_SetDevAttr

3.7. MI_PSPI_DEV

• Description

  Define the PSPI number inside the chip.

• Definition

  typedef MI_S32  MI_PSPI_DEV;
  

• Note

  The parameter value can be set to 0 or 1, respectively representing PSPI0 and PSPI1 inside the chip. PSPI0 is used to represent receiving (RX), and PSPI1 represents sending (RX).

• Related data types and interfaces

  MI_PSPI_CreateDevice

  MI_PSPI_DestroyDevice

  MI_PSPI_Transfer

  MI_PSPI_SetDevAttr

  MI_PSPI_Enable

  MI_PSPI_Disable

4. Error code

PSPI API error codes are shown as follow:

Error Code	Definition	Description
0xA02B201F	MI_PSPI_FAIL	Function run failed
0xA02B2003	MI_ERR_PSPI_ILLEGAL_PARAM	Illegal parameter passed in
0xA02B2006	MI_ERR_PSPI_NULL_PTR	Incoming null pointer
0xA02B200C	MI_ERR_PSPI_NO_MEM	Failed to request memory
0xA02B2010	MI_ERR_PSPI_SYS_NOTREADY	SYS is not ready
0xA02B2015	MI_ERR_PSPI_DEV_NOT_INIT	Device is not initialized
0xA02B2016	MI_ERR_PSPI_DEV_HAVE_INITED	Device has been initialized
0xA02B2017	MI_ERR_PSPI_NOT_ENABLE	Device is not enabled

5. PROCFS介绍

5.1. Pspi cat

• Debugging Information

  # cat /proc/mi_modules/mi_pspi/mi_pspi0
  

  

• Debugging Information Analysis

  Record the current device usage, including interrupt information, device information, and device attributes. It is convenient for users to obtain such information dynamically.

• Parameter Description

  Parameter		Describe
  Irq Info	IrqNum	interrupt number
  	IrqCnt	Count of interrupts generated
  	IrqCnt/Ms	Interrupt count within a certain period of time, unit: ms
  	Ips	Interrupt count per second
  	MasIv/MinIv	The maximum and minimum intervals for completing a task within a certain period of time, unit: ms.
  Dev Info	DevId	Device number
  	DevEnable	Device enabled status
  	ReadyTaskCnt	counts of Ready Task
  	EnqueTaskCnt	counts of Enqueue Task
  	FinishTaskCnt	counts of Finish Task
  	DropTaskCnt	counts of Drop Task
  	BindStatus	Bind Status
  	DevType	Device Type
  	UseMode	Trigger mode
  Attrbute	ChipSelect	pspi cs signal
  	Te_mode	Enable Te mode or not
  	Bit_per_word	Number of bits sent each time
  	rgb_swap	Format and datalanes when sending data to the panel
  	data_lane	The datalanes for sending data to the panel
  	delay_cycle	If SPI_SSCTL has been not setted，it's Delay of two data transfers
  	wait_cycle	If SPI_SSCTL has been setted，it's Delay of two data transfers
  	spi_mode	device mode
  	Max_speed_hz	Maximum clock frequency

5.2. Pspi echo

Function	Get currently pspi device supported commands
Command	echo help > /proc/mi_modules/mi_pspi/mi_pspi0
Parameter Description	NA
Example	echo help > /proc/mi_modules/mi_pspi/mi_pspi0

Function	dump frame data
Command	echo dumpframe [path] > /proc/mi_modules/mi_pspi/mi_pspi0
Parameter Description	[path] dump data storage path
Example	echo dumpframe /mnt/pspiSensorData > /proc/mi_modules/mi_pspi/mi_pspi0

6. MODPARAM.json Introduce

Enter the directory sdk/verify/mi_demo/source/pspi/case_json, modify the file reset.sh and adapt the json file:

reset.sh needs to fill in the GPIO INDEX ID of the reset pin.

./gpio.sh -i 67 -w 0
sleep 1
./gpio.sh -i 67 -w 1

ID 67 is PAD_GPIOA_17 which is connected to the panel as the reset pin.

The adaptation of the json file takes dev0_sensor_datalane2_auto.json as an example:

{
    "pspi":[
        {
            "enable":0,   //disable
            "devid" : 0,  //pspi0
            "devtype": "sensor"
        },
        {
            "enable":1,  //enable the panel connected to pspi1
            "devid" : 1, //pspi1
            "devtype": "panel"
        }

    ],

    ......

    "panel":[
        {
            "devId" : 1,
            "autoTrig":1, //Enable auto trig, refresh the screen in real time
            "temode":1, //Enable TE mode, ensure that the screen is not torn
            "datalane":2 //Single-line, dual-line, or quad-line transmission is optional depending on the panel
        },
        {
            "devId" : 0,
            "autoTrig":1,
            "temode":1,
            "datalane":2
        }
    ]

}