Configuring Linux for an 8-bit RGB LCD on imx6

[heinemann9]

Hello experts,

First of all, I saw I made imx6 (iW-RainboW-G15M) work with evaluation board (with 480x272 LCD display RGB666 18pin).

And now I am trying to make imx6 connected 320x240 LCD display (8bit RGB) work.

Even though I changed dts files and kernel binding txts and driver c files, It doesn't show anything but backlight. I don't know what I have to do.

Does anybody knows about how to solve the problem ?

Any suggestions?

I refered to this site

https://community.nxp.com/t5/i-MX-Processors/Configuring-Linux-for-an-8-bit-RGB-LCD/m-p/387261

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attached LCD information (CHIMEI_LQ035NC111.pdf)

kernel arguments

setenv lcd 'video=mxcfb0:dev=lcd,WQVGA,if=RGB24,bpp=24'

saveenv;boot

modified codes

* drivers/video/fbdev/mxc/mxc_lcdif.c

static struct fb_videomode lcdif_modedb[] = {

/* IWG15M-SM: LCD: Parameters for the WQVGA LCD used */

{

/* 320x240 @ 59 Hz , pixel clk @ 6.5MHz */

"WQVGA", 59, 320, 240, 156000, 68, 20, 18, 4, 1, 1,

FB_SYNC_CLK_LAT_FALL,

FB_VMODE_NONINTERLACED,

0,},

....

}

* arch/arm/boot/dts/imx6qdl-iwg15m-sm.dtsi

- mxcfb1: fb@0 {

- compatible = "fsl,mxc_sdc_fb";

- disp_dev = "lcd";

- interface_pix_fmt = "RGB24";

- mode_str ="WQVGA";

- default_bpp = <24>;

- int_clk = <0>;

- late_init = <0>;

- status = "disabled";

- };

+ mxcfb1: fb@0 {

+ compatible = "fsl,mxc_sdc_fb";

+ disp_dev = "lcd";

+ interface_pix_fmt = "RGB24";

+ mode_str ="WQVGA";

+ default_bpp = <24>;

+ int_clk = <0>;

+ late_init = <0>;

+ status = "disabled";

+ };

* arch/arm/boot/dts/imx6qd-iwg15m-sm_ldoactive.dts

lvds-channel@0 {

fsl,data-mapping = "spwg";

- fsl,data-width = <18>;

+ fsl,data-width = <24>;

primary;

crtc = "ipu2-di0";

status = "okay";

@@ -49,9 +49,9 @@

display-timings {

native-mode = <&timing0>;

timing0: ldb-svga {

- clock-frequency = <40000000>;

- hactive = <800>;

- vactive = <600>;

+ clock-frequency = <15600000>;

+ hactive = <320>;

+ vactive = <240>;

hback-porch = <8>;

hfront-porch = <8>;

vback-porch = <6>;

* Documentation/devicetree/bindings/fb/mxsfb.txt

@@ -22,6 +22,7 @@ lcdif@80030000 {

compatible = "fsl,imx28-lcdif";

reg = <0x80030000 2000>;

interrupts = <38 86>;

+ status = "okay";

display: display {

bits-per-pixel = <32>;

@@ -30,14 +31,14 @@ lcdif@80030000 {

display-timings {

native-mode = <&timing0>;

timing0: timing0 {

- clock-frequency = <33500000>;

- hactive = <800>;

- vactive = <480>;

- hfront-porch = <164>;

- hback-porch = <89>;

+ clock-frequency = <15600000>;

+ hactive = <320>;

+ vactive = <240>;

+ hfront-porch = <20>;

+ hback-porch = <68>;

hsync-len = <10>;

- vback-porch = <23>;

- vfront-porch = <10>;

+ vback-porch = <18>;

+ vfront-porch = <4>;

vsync-len = <10>;

hsync-active = <0>;

vsync-active = <0>;