K230 Video Output API Reference

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Directory

[TOC]

Preface

Overview

This document mainly introduces the functions and usage of the video output system control module, and the functions and usage of other modules will be discussed in special documents.

Reader object

This document (this guide) is intended primarily for:

• Technical Support Engineer

• Software Development Engineer

Definition of acronyms

abbreviation	illustrate
VO	Video output
DSI	Display Serial Interface

Revision history

Document version number	Modify the description	Author	date
V1.0	Initial edition	System Software Department	2023-03-10

1. Overview

VO (Video Output) module actively reads video and graphics data from the corresponding location in memory, and outputs video and graphics through the corresponding display device. Display/write-back devices, video layers, and graphics layer conditions supported by the chip.

LAYER SUPPORT:

	LAYER0	LAYER1	LAYER2
Input format	YUV420 NV12	YUV420 NV12	YUV420 NV12 YUV422 NV16 ?
Maximum resolution	1920x1080	1920x1080	1920x1080
Overlay display	Supports configurable overlay order	Supports configurable overlay order	Supports configurable overlay order
Rotation	√	√	-
Scaler	√	-	-
Mirror	√	√	-
Gray	√	√	-
Independent switch	√	√	√

OSD layer support

	OSD0	OSD1	OSD2	OSD3
Input format	RGB888 RGB565 ARGB8888 Monochrome-8-bit RGB4444 RGB1555	RGB888 RGB565 ARGB8888 Monochrome-8-bit RGB4444 RGB1555	RGB888 RGB565 ARGB8888 Monochrome-8-bit RGB4444 RGB1555	RGB888 RGB565 ARGB8888 Monochrome-8-bit RGB4444 RGB1555
Maximum resolution	1920x1080	1920x1080	1920x1080	1920x1080
Overlay display	Supports configurable overlay order	Supports configurable overlay order	Supports configurable overlay order	Supports configurable overlay order
ARGB 265 grade ALPHA	√	√	√	√
Independent switch	√	√	√	√

1.1 Hardware Description

This hardware introduction is based on EVBLP3

1.1.1 MIPI interface

The hardware pins on EVBLP3 are as follows:

• screen touch is I2C4 (SCL: GPIO7, SDA GPIO8)

• screen touch rst：gpio29， int：gpio30

• screen rst：gpio9，backlight：gpio31

• The pins of MIPI correspond one-to-one with the pins of the screen

1.1.2 Physical drawings

• Figure 1 is the MIPI interface, using a flexible cable

• Figure 2 is the MIPI signal test point, including four data lines and one CLK line

1.2 Software Description

Video output software configuration is divided into 3 parts configuration: phy configuration, DSI configuration, VO configuration,

1.2.1 PHY configuration process

The frequency of PHY needs to configure three parameters, calculate PLL, configure VOCs, configure FREQ, according to these three parameters can determine the frequency of TXPHY, each parameter is calculated as follows.

1.2.1.1 Calculate the PLL of PHY

The data rate is given by twice the PLL output clock phase frequency: data rate (Gbps) = PLL Fout(GHz) * 2, and the output frequency is a function of the input reference frequency and the multiplier/divider ratio. The PLL for calculating PHY is divided into 4 ranges to do calculations, different frequencies correspond to different frequencies, which can be determined in the following ways:

M	m+2
N	n+1
Fclkin	24M

For：

However in this need to follow the following restrictions:

For：

For：

For：

Each of the above for corresponds to a PLL level, and different levels correspond to different calculation formulas and limits, and the calculation example is as follows:

Example：

The rate of mipi is 445.5M: so the rate of pll is 222.75M, and the second formula should be selected, calculated as follows

222750000 = 1M / 2N = (m+2) / 2(n+1) * 24000000 , the finishing formula is as follows:

222.75n + 198.75 = 12m is calculated by excel as follows:

The resulting m = 295 and n = 15.

Configure the m and n in the PLL are integer values, if all the values are not integers, you need to add 1 and subtract 1 from the values of m and n, push back to see which frequency you need to be the closest, and then verify whether it is available, you can’t repeat the above operation.

1.2.1.2 Configure VOC for PHY

The VOC configured with PHY can be queried according to the table:

Example：

The rate of mipi is 445.5M: so the rate of the pll is 222.75M, and VOC = 010111 = 0x17

1.2.1.3 Configure FreQ

The FREQ of the configured PHY can be queried according to the table:

Example：

The rate of mipi is 445.5M: the rate of pll is 222.75M, freq selects 0100101, when configuring this, you need to set the highest bit [7] = 1, all freq = 10100101 = 0xa5

1.2.2 Configuration of DSI

DSI (Display Serial Interface) is part of a consortium of MIPI-defined communication protocols, mainly digital controllers that implement all protocol functions defined in the MIPI DSI specification, including bidirectional PHYs with two and four channels.

DSI mainly configures the screen in the software to display functions with timing and sending commands.

1.2.2.1 Configure the timing of the display

Each manufacturer’s screen will have a set of timing for screen control, mainly including the control timing of the frame and the control timing of a line, as shown in the following figure:

These parameters are also used in DSI, and the configured timing and screen are consistent.

1.2.2.2 DSI send command

DSI needs to enter LP mode before sending commands, and the APIs required are as follows:

• kd_mpi_dsi_set_lp_mode_send_cmd

• kd_mpi_dsi_send_cmd

The data sent is sent in 8 bits, and the long or short packet will be automatically selected according to the quantity.

1.2.2.3 DSI’s self-test mode

The DSI self-test mode will send the data of the color bar according to the self-configured DSI timing to be sent, so that it does not rely on VO to read data from the DDR, and the test mode is shown as follows:

The 24-bit interface is used between DSI and vo, so the configured color bar is the effect shown above, and the use method only needs to enable the color bar after configuring DSI, and the API is as follows

• kd_mpi_dsi_set_test_pattern

1.2.3 Configuration of VO

VO (video output) is mainly VO (Video Output) module actively read video and graphics data from the corresponding position of memory, and output video and graphics through the corresponding display device, VO This part contains two configurations, one is the configuration of the time, the other is the configuration of the video layer

1.2.3.1 VO timing configuration

The timing configuration of VO and the timing configuration of DSI use the same configuration parameters, and the specific rows and columns are the same, just see the introduction of DSI timing

1.2.3.2 Layer configuration for VO

The VO layer currently supports 3 layers and 4 OSD layers. The layer can only display the image format of the YUV (the features supported by layer0 and layer1 are shown in the diagram).

1.2.3.3 Configuration of the write-back function of VO

VO also supports the write-back function, which can verify whether the VO configuration is correct, and after the VO configuration is completed, the data will be written back to DDR to facilitate verification of whether the VO configuration is abnormal

1.2.4 Debugging method of VO module

1.2.4.1 Test method for screens

• You can enter the self-test mode through the LP command configuration screen to see if the resulting image is normal

• Read the screen registers with the LP command to see if they are returned

1.2.4.2 Test methods for DSI

• After configuring DSI, let the screen enter the self-test mode, measure the signal to see that it is normal, and you can also see whether the screen produces a color bar image

• Check the PHY’s err status register to see if there is an err status, which can be viewed through proc

1.2.4.3 Test methods for VO

• After the VO configuration is completed, turn on the writeback function to check whether it is consistent with the configuration requirements

• Read the err status register of DSI to see if there is underflow and overflow in the data transfer between VO and dsi, and if so, try again with the appropriate timing

2. API Reference

2.1 TXPHY

This function module provides the following APIs:

• kd_mpi_set_mipi_phy_attr

2.1.1 kd_mpi_set_mipi_phy_attr

【Description】

Set the frequency of PHY

【Syntax】

k_s32 kd_mpi_set_mipi_phy_attr(k_vo_mipi_phy_attr *attr)

【Parameters】

Parameter name	description	Input/output
attr	Description of the frequency structure of the PHY	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.2 CIO

This function module provides the following APIs:

• kd_mpi_dsi_set_attr

• kd_mpi_dsi_enable

• kd_mpi_dsi_send_cmd

• kd_mpi_dsi_read_pkg

• kd_mpi_dsi_set_test_pattern

• kd_mpi_dsi_set_lp_mode_send_cmd

2.2.1 kd_mpi_dsi_set_attr

【Description】

Configure the DSI property parameters

【Syntax】

k_s32 kd_mpi_dsi_set_attr(k_display_mode *ATTR)【Parameters】

Parameter name	description	Input/output
attr	DSI property parameter	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.2.2 kd_mpi_dsi_enable

【Description】

Open DSI

【Syntax】

k_s32 kd_mpi_dsi_enable(void)

【Parameters】

none

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.2.3 kd_mpi_dsi_send_cmd

【Description】

DSI sends command

【Syntax】

k_s32 kd_mpi_dsi_send_cmd(k_u8 *data, k_s32 cmd_len)

【Parameters】

Parameter name	description	Input/output
data	Data sent	input
cmd_len	Data length	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.2.4 kd_mpi_dsi_read_pkg

【Description】

DSI read command

【Syntax】

k_s32 kd_mpi_dsi_read_pkg(k_u8 *rx_buf, k_s32 cmd_len)

【Parameters】

Parameter name	description	Input/output
rx_buf,	Accepted data	input
cmd_len	Data length	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.2.5 kd_mpi_dsi_set_test_pattern

【Description】

Configure DSI to enter self-test mode

【Syntax】

k_s32 kd_mpi_dsi_set_test_pattern(void)

【Parameters】、

not

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.2.6 kd_mpi_dsi_set_lp_mode_send_cmd

【Description】

Configure DSI to enter LP Mode to send commands

【Syntax】

k_s32 kd_mpi_dsi_set_lp_mode_send_cmd(void)

【Parameters】

none

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3 VO

• kd_mpi_vo_init

• kd_mpi_vo_set_dev_param

• kd_mpi_vo_enable_video_layer

• kd_mpi_vo_disable_video_layer

• kd_mpi_vo_enable

• kd_mpi_vo_chn_insert_frame

• kd_mpi_vo_chn_dump_frame

• kd_mpi_vo_chn_dump_release

• kd_mpi_vo_osd_enable

• kd_mpi_vo_osd_disable

• kd_mpi_vo_set_video_osd_attr

• kd_mpi_vo_set_wbc_attr

• kd_mpi_vo_enable_wbc

• kd_mpi_vo_disable_wbc

• kd_display_reset

• kd_display_set_backlight

• kd_mpi_vo_set_user_sync_info

• kd_mpi_vo_draw_frame

2.3.1 kd_mpi_vo_init

【Description】

VO initializes the default parameters

【Syntax】

k_s32 kd_mpi_vo_init(void);

【Parameters】

none

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.2 kd_mpi_vo_set_dev_param

【Description】

DSI sends the command

【Syntax】

k_s32 kd_mpi_vo_set_dev_param(k_vo_pub_attr *attr)

【Parameters】

Parameter name	description	Input/output
attr	Video output device public property structure pointer.	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.3 kd_mpi_vo_enable_video_layer

【Description】

Configure layer layer property parameters

【Syntax】

k_s32 kd_mpi_vo_enable_video_layer(k_vo_layer layer)

【Parameters】

Parameter name	description	Input/output
layer	Video output video layer number Value range [0 – K_MAX_VO_LAYER_NUM]	input
attr	Video layer property structure pointer	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.4 kd_mpi_vo_disable_video_layer

【Description】

Turn off the video layer

【Syntax】

k_s32 kd_mpi_vo_disable_video_layer(k_vo_layer layer)

【Parameters】

Parameter name	description	Input/output
layer	Video output video layer number Value range [0 – K_MAX_VO_LAYER_NUM]	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file:

• Library file:

【Note】

none

【Example】

none

【See Also】

none

2.3.5 kd_mpi_vo_enable

【Description】

Open VO

【Syntax】

k_u8 kd_mpi_vo_enable(void);

【Parameters】

none

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file:

• Library file:

【Note】

none

【Example】

none

【See Also】

none

2.3.6 kd_mpi_vo_chn_insert_frame

【Description】

Insert frames into VO’s channel

【Syntax】

k_s32 kd_mpi_vo_chn_insert_frame(k_u32 chn_num, k_video_frame_info *vf_info)

【Parameters】

Parameter name	description	Input/output
chn_num	Number of channels	input
vf_info	The structure pointer for the video frame.	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_video_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.7 kd_mpi_vo_chn_dump_frame

【Description】

Grab one frame of data from VO’s channel

【Syntax】

k_s32 kd_mpi_vo_chn_dump_frame(k_u32 chn_num, k_video_frame_info *vf_info, k_u32 timeout_ms);

【Parameters】

Parameter name	description	Input/output
chn_num	Channel ID	input
vf_info	The structure pointer for the video frame	input
timeout_ms	Timeout	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_video_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.8 kd_mpi_vo_chn_dump_release

【Description】

Release the grab frame

【Syntax】

k_s32 kd_mpi_vo_chn_dump_release(k_u32 chn_num, const k_video_frame_info *vf_info);

【Parameters】

Parameter name	description	Input/output
chn_num	Channel ID	input
vf_info	The structure pointer for the video frame	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_video_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.9 kd_mpi_vo_osd_enable

【Description】

Open the OSD layer

【Syntax】

k_s32 kd_mpi_vo_osd_enable(k_vo_osd layer)

【Parameters】

Parameter name	description	Input/output
layer	Video output video layer number Value range [0 – K_MAX_VO_OSD_NUM]	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.10 kd_mpi_vo_osd_disable

【Description】

Turn off the OSD layer

【Syntax】

k_s32 kd_mpi_vo_osd_disable(k_vo_osd layer)

【Parameters】

Parameter name	description	Input/output
layer	Video output video layer number Value range [0 – K_MAX_VO_OSD_NUM]	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.11 kd_mpi_vo_set_video_osd_attr

【Description】

Set OSD layer properties

【Syntax】

k_s32 kd_mpi_vo_set_video_osd_attr(k_vo_osd layer, k_vo_video_osd_attr *attr)

【Parameters】

Parameter name	description	Input/output
layer	Video output video layer number Value range [0 – K_MAX_VO_OSD_NUM]	input
OSD layer property parameters	OSD layer property parameters	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.12 kd_mpi_vo_set_wbc_attr

【Description】

Set the write-back property

【Syntax】

k_s32 kd_mpi_vo_set_wbc_attr(k_vo_wbc_attr *attr)

【Parameters】

Parameter name	description	Input/output
attr	The writeback property parameter	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.13 kd_mpi_vo_enable_wbc

【Description】

使能writeback

【Syntax】

k_s32 kd_mpi_vo_enable_wbc(void)

【Parameters】

none

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.14 kd_mpi_vo_disable_wbc

【Description】

Close writeback

【Syntax】

k_s32 kd_mpi_vo_disable_wbc(void)

【Parameters】

none

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.15 kd_display_reset

【Description】

Reset the video output subsystem

【Syntax】

k_s32 kd_display_reset(void)

【Parameters】

none

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.16 kd_display_set_backlight

【Description】

Reset the screen and turn on the backlight

【Syntax】

k_s32 kd_display_set_backlight(void)

【Parameters】

none

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.17 kd_mpi_vo_set_user_sync_info

【Description】

Set the user interface timing information to configure the clock source, clock size, and clock division ratio

【Syntax】

k_s32 kd_mpi_vo_set_user_sync_info(k_vo_user_sync_info *sync_info)

【Parameters】

Parameter name	description	Input/output
pre_div	Number of user crossovers	input
clk_en	Crossover enable enable

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.18 kd_mpi_vo_draw_frame

【Description】

Picture frame

【Syntax】

k_s32 kd_mpi_vo_draw_frame(k_vo_draw_frame *frame)

【Parameters】

Parameter name	description	Input/output
frame	Property parameters for the picture frame	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h

• Library file: libvo.a

【Note】

none

【Example】

none

【See Also】

none

2.3.19 kd_mpi_get_connector_info

【Description】

Gets the data structure of the Connecor connector by connection type

【Syntax】

k_s32 kd_mpi_get_connector_info(k_connector_type connector_type, k_connector_info *connector_info)

【Parameters】

Parameter name	description	Input/output
connector_type	The type of connector	input
connector_info	The data structure of the connector	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h k_connector_comm.h

• Library file: libvo.a libconnector.a

【Note】

none

【Example】

none

【See Also】

none

2.3.20 kd_mpi_connector_open

【Description】

Gets the data structure of the Connecor connector by connection type

【Syntax】

k_s32 kd_mpi_connector_open(const char *connector_name)

【Parameters】

Parameter name	description	Input/output
connector_name	The device node of the connector	input

【Return value】

Return value	description
fd	Successfully returns the ID of the open fd
Less than 0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h k_connector_comm.h

• Library file: libvo.a libconnector.a

【Note】

none

【Example】

none

【See Also】

none

2.3.21 kd_mpi_connector_power_set

【Description】

Power on the connector

【Syntax】

k_s32 kd_mpi_connector_power_set(k_s32 fd, k_bool is)

【Parameters】

Parameter name	description	Input/output
fd	The device node of the connector	input
on	Switch of connector device	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h k_connector_comm.h

• Library file: libvo.a libconnector.a

【Note】

none

【Example】

none

【See Also】

none

2.3.22 kd_mpi_connector_init

【Description】

vo connector init

【Syntax】

k_s32 kd_mpi_connector_init(k_s32 fd, k_connector_info info)

【Parameters】

Parameter name	description	Input/output
fd	The device node of the connector	input
info	Parameters for connector initialization	input

【Return value】

Return value	description
0	Succeed.
Non-0	For failures, see Error codes.

【Differences】

none

【Requirement】

• Header file: mpi_vo_api.h k_vo_comm.h k_connector_comm.h

• Library file: libvo.a libconnector.a

【Note】

none

【Example】

none

【See Also】

none

3. Data Type

3.1 VO

3.1.1 k_vo_intf_sync

【Description】

Define the resolution and frame rate in the video

【Definition】

typedef enum {  K_VO_OUT_1080P30,  K_VO_OUT_1080P60, } k_vo_intf_sync;

【Members】

Member name	description
K_VO_OUT_1080P30	1080 represents 1920x1080 PIX. 30 means 30fps
K_VO_OUT_1080P60	1080 represents 1920x1080 PIX. 60 means 60fps
K_VO_OUT_1080x1920P30	1080x1920 represents 1080x1920 PIX. 30 means 30fps
K_VO_OUT_11080x1920P60	1080x1920 represents 1080x1920 PIX. 60 means 60fps

【Note】

none

【See Also】

3.1.2 k_vo_intf_type

【Description】

Define the resolution and frame rate in the video

【Definition】

typedef enum {  K_VO_INTF_MIPI = 0, } k_vo_intf_type;

【Members】

Member name	description
K_VO_INTF_MIPI	MIPI interface

【Note】

none

【See Also】

3.1.3 k_pixel_format

【Description】

The data formats supported by the layer in the display, only the supported data formats are listed in the structure below, not all data formats

【Definition】

typedef enum {  PIXEL_FORMAT_YVU_PLANAR_420,  PIXEL_FORMAT_YVU_PLANAR_422,  PIXEL_FORMAT_RGB_565,  PIXEL_FORMAT_RGB_888,  PIXEL_FORMAT_ARGB_8888,  PIXEL_FORMAT_ARGB_4444,  PIXEL_FORMAT_ARGB_1555,  PIXEL_FORMAT_RGB_MONOCHROME_8BPP, } k_pixel_format;

【Members】

Member name	description
PIXEL_FORMAT_YVU_PLANAR_420	YUV420 NV12
PIXEL_FORMAT_YVU_PLANAR_422	YUV422 NV16
PIXEL_FORMAT_RGB_565	RGB565
PIXEL_FORMAT_RGB_888	RGB888
PIXEL_FORMAT_RGB_MONOCHROME_8BPP	8 BIT RGB
PIXEL_FORMAT_ARGB_8888	ARGB8888
PIXEL_FORMAT_ARGB_4444	ARGB4444
PIXEL_FORMAT_ARGB_1555	ARGB1444

【Note】

none

【See Also】

none

3.1.4 k_vo_osd

【Description】

The number of OSDs and the number of each OSD

【Definition】

typedef enum {  K_VO_OSD0,  K_VO_OSD1,  K_VO_OSD2,  K_VO_OSD3,  K_MAX_VO_OSD_NUM, } k_vo_osd;

【Members】

Member name	description
K_VO_OSD0	OSD 0
K_VO_OSD1	OSD 1
K_VO_OSD2	OSD 2
K_VO_OSD3	OSD 3
K_MAX_VO_OSD_NUM	OSD layer maximum number flag

【Note】

none

【See Also】

none

3.1.5 k_vo_layer

【Description】

The number of layers and the number of each layer

【Definition】

typedef enum {  K_VO_LYAER0 = 0,  K_VO_LYAER1,  K_VO_LYAER2,  K_MAX_VO_LAYER_NUM, } k_vo_layer;

Members】

Member name	description
K_VO_LYAER0	Layer 0
K_VO_LYAER1	Layer 1
K_VO_LYAER2	Layer 2
K_VO_LYAER3	Layer 3
K_MAX_VO_LAYER_NUM	Maximum number of layers flag

【Note】

none

【See Also】

none

3.1.6 k_vo_rotation

【Description】

Features supported by Layer rotation

【Definition】

typedef enum {  K_ROTATION_0 = (0x01L << 0),  K_ROTATION_90 = (0x01L << 1),  K_ROTATION_180 = (0x01L << 2),  K_ROTATION_270 = (0x01L << 3), } k_vo_rotation;

【Note】

none

【See Also】

none

3.1.7 k_vo_mirror_mode

【Description】

Features supported by Layer mirror.

【Definition】

typedef enum {  K_VO_MIRROR_NONE = (0x01L << 4),  K_VO_MIRROR_HOR = (0x01L << 5),  K_VO_MIRROR_VER = (0x01L << 6),  K_VO_MIRROR_BOTH = (0x01L << 7), } k_vo_mirror_mode;

【Members】

Member name	description
K_VO_MIRROR_NONE	Layer no mirror
K_VO_MIRROR_HOR	Layer horizontal mirror
K_VO_MIRROR_VER	Layer vertical mirror
K_VO_MIRROR_BOTH	Layer does vertical and horizontal mirrors

【Note】

none

【See Also】

none

3.1.8 k_vo_user_sync_info

【Description】

User-defined clock crossover.

【Definition】

typedef struct {  k_u32 ext_div;  k_u32 dev_div;  k_u32 clk_en; } k_vo_user_sync_info;

【Members】

Member name	description
ext_div;	CLKEXT crossover
dev_div	Clk crossover
clk_en	Display clock enable

【Note】

none

【See Also】

none

3.1.9 k_vo_point

【Description】

Define the coordinate information structure.

【Definition】

typedef struct {  k_u32 x;  k_u32 y; }k_vo_point;

【Members】

Member name	description
x	abscissa
y	ordinate

【Note】

none

【See Also】

none

3.1.10 k_vo_size

【Description】

Defines the size information structure.

【Definition】

typedef struct {  k_u32 width;  k_u32 height; } k_vo_size;

【Members】

Member name	description
width	width
height	height

【Note】

none

【See Also】

none

3.1.11 k_vo_video_layer_attr

【Description】

Define the display layer layer properties

【Definition】

typedef struct {  k_point display_rect;  k_size img_size;  k_pixel_format pixel_format;  k_u32 stride;  k_u32 uv_swap_en;  k_u32 alptha_tpye; } k_vo_video_layer_attr;

【Members】

Member name	description
display_rect;	The starting position of the OSD layer
img_size	Image resolution structure, that is, the size of the composite picture
pixel_format	Supported data formats for the video layer
stride	Stride of images
uv_swap_en	UV swap
alptha_tpye	The type of Alptha that is used only in the OSD layer. It is divided into fixed alpha (which can be divided into 256 levels), R in RGB as the alpha channel, G in RGB as the alpha channel, B in RGB as the alpha channel, and alpha channel as alpha

【Note】

alptha_tpye is only used for the OSD layer

【See Also】

none

3.1.12 k_vo_wbc_attr

【Description】

Define the writeback property.

【Definition】

typedef struct {  k_vo_size target_size;  k_pixel_format pixel_format;  k_u32 stride;  k_u32 y_phy_addr; } k_vo_wbc_attr;

【Members】

Member name	description
target_size	The target size for write-back
pixel_format	The format of the data that is written back
pixel_format	data format
stride;	Stride written back
y_addr	The physical address of the image write-back

【Note】

y_addr Space needs to be allocated

【See Also】

none

3.1.13 k_vo_pub_attr

【Description】

Configure the public properties of the video output device.

【Definition】

typedef struct {  k_u32 bg_color;  k_vo_intf_type intf_type;  k_vo_intf_sync intf_sync;  k_vo_display_resolution *sync_info;  } k_vo_pub_attr;

【Members】

Member name	description
bg_color	Background color
type	Interface type, currently only MIPI is supported
intf_sync	Resolution and frame rate in the video
sync_info	The timing of the image output

【Note】

none

【See Also】

none

3.1.14 k_vo_scaler_attr

【Description】

Define the scaler property

【Definition】

typedef struct{  k_size in_size;  k_size out_size;  k_u32 stride; }k_vo_scaler_attr;

【Members】

Member name	description
in_size	The dimensions entered
out_size	The dimensions of the output
stride	stride
y_addr	The physical address of the image write-back

【Note】

none

【See Also】

none

3.1.15 k_vo_draw_frame

【Description】

Defines the properties of the frame

【Definition】

typedef struct {  k_u32 draw_en;  k_u32 line_x_start;  k_u32 line_y_start;  k_u32 line_x_end;  k_u32 line_y_end;  k_u32 frame_num; }k_vo_draw_frame;

【Members】

Member name	description
draw_en	Picture frame enabled
line_x_start	The start in the X direction
line_y_start	The start of the y direction
line_x_end	The end point in the X direction
line_y_end	The end point in the y direction
frame_num	num sign in the current box [0 - 16]

【Note】

none

【See Also】

none

3.1.16 k_vo_display_resolution

【Description】

Display timing。

【Definition】

typedef struct{  k_u32 PCLK;  k_u32 phyclk;  k_u32 htotal;  k_u32 hdisplay;  k_u32 hsync_len;  k_u32 hback_porch;  k_u32 hfront_porch;  k_u32 vtotal;  k_u32 vdisplay;  k_u32 vsync_len;  k_u32 vback_porch;  k_u32 vfront_porch; } k_vo_display_resolution;

【Members】

Member name	description
pclk	The pix clk frequency of VO
phyclk	The frequency of D-Phy
htotal	The total pixels of a row
hdisplay	The number of valid pixels per row
hsync_len	The number of pixels that the row synchronizes
hback_porch	The number of pixels on the back porch
hfront_porch	The number of pixels on the front porch
vtotal	Total number of rows
vdisplay	The number of rows valid for one frame
vsync_len	The number of pixels in which the frame is synchronized
vback_porch	The number of rows on the back porch
vfront_porch	The number of rows on the front porch

【Note】

none

【See Also】

none

3.1.17 k_vo_mipi_phy_attr

【Description】

A structure that defines the MIPI PHY frequency

【Definition】

typedef struct {  k_u32 n;  k_u32 m;  k_u32 voc;  k_u32 phy_lan_num;  k_u32 hs_freq; }k_vo_mipi_phy_attr;

【Members】

Member name	description
n	Pll coefficient
m	Pll coefficient
voc	Pll coefficient
hs_freq	The frequency range of Phy
phy_lan_num	The number of LANs for Phy

【Note】

none

【See Also】

none

3.1.18 k_vo_video_osd_attr

【Description】

Configure the public properties of the OSD layer.

【Definition】

typedef struct {  k_vo_point display_rect;  k_vo_size img_size;  k_pixel_format pixel_format;  k_u32 stride;  k_u8 global_alptha; } k_vo_video_osd_attr;

【Members】

Member name	description
display_rect	Location information
img_size	Valid size
pixel_format	data format
stride;	Stride
global_alptha	transparency

【Note】

none

【See Also】

none

3.1.19 k_video_frame_info

【Description】

One frame of information.

【Definition】

typedef struct {  k_video_frame v_frame;  k_u32 pool_id;  k_mod_id mod_id; } k_video_frame_info;

【Members】

Member name	description
v_frame	Information of the frame
pool_id	VB Party ID
mod_id	The ID of the video frame

【Note】

none

【See Also】

none

3.1.20 k_connector_type

【Description】

The type of connection screen.

【Definition】

typedef enum {  HX8377_V2_MIPI_4LAN_1080X1920_30FPS;  LT9611_MIPI_4LAN_1920X1080_30FPS; } k_connector_type;

【Members】

Member name	description
v_frame	Information about the frame
HX8377_V2_MIPI_4LAN_1080X1920_30FPS	HX8377 Screen initialization
LT9611_MIPI_4LAN_1920X1080_30FPS	HDMI 1080p initialization

【Note】

none

【See Also】

none

3.1.21 k_dsi_lan_num

【Description】

The number of lanes for DSI.

【Definition】

typedef enum {  K_DSI_1LAN = 0,  K_DSI_2LAN = 1,  K_DSI_4LAN = 3, } k_dsi_lan_num;

【Members】

Member name	description
K_DSI_1LAN	1-line mode
K_DSI_2LAN	2-wire mode
K_DSI_4LAN	4-wire mode

【Note】

none

【See Also】

none

3.1.22 k_dsi_work_mode

【Description】

The operating mode of DSI

【Definition】

typedef enum{  K_BURST_MODE = 0,  K_NON_BURST_MODE_WITH_SYNC_EVENT = 1,  K_NON_BURST_MODE_WITH_PULSES = 2, } k_dsi_work_mode;

【Members】

Member name	description
K_BURST_MODE	DSI works in Brust Mode
K_NON_BURST_MODE_WITH_SYNC_EVENT	DSi work in Non Brust Event Mode
K_NON_BURST_MODE_WITH_PULSES	DSI work in Non Brust Pulses Mode

【Note】

none

【See Also】

none

3.1.23 k_vo_dsi_cmd_mode

【Description】

The pattern in which DSI sends commands.

【Definition】

typedef enum {  K_VO_LP_MODE,  K_VO_HS_MODE, } k_vo_dsi_cmd_mode;

【Members】

Member name	description
K_VO_LP_MODE	LP mode sends commands
K_VO_HS_MODE	HS mode sends commands

【Note】

none

【See Also】

none

3.1.24 k_connectori_phy_attr

【Description】

Connector Connector Configuration PHY information.

【Definition】

typedef struct {  k_u32 n;  k_u32 m;  k_u32 voc;  k_u32 hs_freq; } k_connectori_phy_attr;

【Members】

Member name	description
n	Pll coefficient
m	Pll coefficient
voc	Pll coefficient
hs_freq	The frequency range of Phy

【Note】

none

【See Also】

none

3.1.25 k_connector_info

【Description】

Information about the connector.

【Definition】

typedef struct {  const char *connector_name;  k_u32 screen_test_mode;  k_u32 dsi_test_mode;  k_u32 bg_color;  k_u32 intr_line;  k_dsi_lan_num lan_num;  k_dsi_work_mode work_mode;  k_vo_dsi_cmd_mode cmd_mode;  k_connectori_phy_attr phy_attr;  k_vo_display_resolution resolution;  k_connector_type type; } k_connector_info;

【Members】

Member name	description
connector_name	connector name
screen_test_mode	screen test mode
dsi_test_mode	dsi test mode
bg_color	background color
intr_line	Break line number
work_mode	dsi work mode
phy_attr	Parameters of mipi phy
lan_num	mipi lan num
resolution	Parameters of display
type	connector type

【Note】

none

【See Also】

none

4. Error codes

Table 41 VO API error codes

Error code	Macro definitions	description
0xa00b8006	K_ERR_VO_NULL_PTR	Parameter null pointer error
0xa00b8001	K_ERR_VO_INVALID_DEVID	Invalid dev id
0xa00b8002	K_ERR_VO_INVALID_CHNID	Invalid chn id
0xa00b8005	K_ERR_VO_UNEXIST	The video cache does not exist
0xa00b8004	K_ERR_VO_EXIST	Video cache exists
0xa00b8003	K_ERR_VO_ILLEGAL_PARAM	The parameter setting is invalid
0xa00b8010	K_ERR_VO_NOTREADY	VO is not ready
0xa00b8012	K_ERR_VO_BUSY	The system is busy
0xa00b8007	K_ERR_VO_NOT_CONFIG	Configuration is not allowed
0xa00b8008	K_ERR_VO_NOT_SUPPORT	Unsupported operations
0xa00b8009	K_ERR_VO_NOT_PERM	Operation is not allowed
0xa00b800c	K_ERR_VO_NOMEM	Failed to allocate memory
0xa00b800d	K_ERR_VO_NOBUF	No buffs
0xa00b800e	K_ERR_VO_BUF_EMPTY	Buf is empty
0xa00b800f	K_ERR_VO_BUF_FULL	Buf is full
0xa00b8011	K_ERR_VO_BADADDR	Wrong address
0xa00b8012	K_ERR_VO_BUSY	The system is busy