How can I display 1024x768 resolution data on LVDS display in I.MX8QM board

[mallibeerala]

Hi,

How can I display 1024x768 resolution data on LVDS display in I.MX8QM board.

I am able to display 1920x1200 resolution data on LVDS display.

Dtb file: imx8qm-mek-jdi-wuxga-lvds1-panel.dtb

Kernel Version - 5.15.32

Here for different resolutions I am changing compatible filed in lvds1_panel.

for 1920x1200 resolution, compatible = "jdi, tx26d202vm0bwa" -> working

for 1024x768 resolution, compatible = "innolux, g121x1-l03" -> not working

Please help us to resolve this Issue.

Thanks,
Mallikarjuna

[Zhiming_Liu]

Can you share your changes and timing?

[mallibeerala]

Hi Zhiming,

I am using below timings.

static const struct drm_display_mode innolux_g121x1_l03_mode = {
.clock = 65000,
.hdisplay = 1024,
.hsync_start = 1024 + 0,
.hsync_end = 1024 + 1,
.htotal = 1024 + 0 + 1 + 320,
.vdisplay = 768,
.vsync_start = 768 + 38,
.vsync_end = 768 + 38 + 1,
.vtotal = 768 + 38 + 1 + 0,
.flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
};

static const struct panel_desc innolux_g121x1_l03 = {
.modes = &innolux_g121x1_l03_mode,
.num_modes = 1,
.bpc = 6,
.size = {
.width = 246,
.height = 185,
            },
.delay = {
.enable = 200,
.unprepare = 200,
.disable = 400,
           },
};

Thanks,
Mallikarjuna

[Zhiming_Liu]

You need modify lvds-channel node:

fsl,data-mapping = "spwg";
fsl,data-width = <24>;

The data-width of your panel should be 18 and you need also confirm the data-mapping. 

[mallibeerala]

Hi,

I am setting LVDS node as below settings and I configured my LVDS display as 8bit Input Mode

&ldb2 {
status = "okay";
fsl,dual-channel;

lvds-channel@0 {
fsl,data-mapping = "spwg";
fsl,data-width = <24>;
status = "okay";

port@1 {
reg = <1>;

lvds1_out: endpoint {
remote-endpoint = <&panel_lvds1_in>;
};
};
};
};

please find the attached dtsi file.

Thanks,
Mallikarjuna

[Zhiming_Liu]

You set bpc=6 in timing, you can try bpc=8

[mallibeerala]

Hi,

I am able to display on LVDS display but displaying in SPLIT screen.

how can I disable split screen.

Kernel  Version: 5.15.32.

Thanks,
Mallikarjuna

[Zhiming_Liu]

Hi @mallibeerala 

Have you add  "fsl,dual-channel" property in your ldb node?

Best Regards

Zhiming