i.MX ProcessorsのトピックRe: i.MX6 LCD display does not work when using yocto

i.MX6 LCD display does not work when using yocto

宗標廖 — Tue, 24 Feb 2015 03:10:59 GMT

Hello,Community

I am now working on Freescale imx6dlsabreauto board with Yocto L3.10.17_1.0.2.

I connected a 7" 800 x 480 LCD display,and set the kernel command line

as below:

setenv mmcargs 'setenv bootargs console=${console},${baudrate} ${smp} root=${mmcroot} video=mxcfb0:dev=lcd,CLAA-WVGA,if=RGB565'

After the kernel started,the LCD display did not work(it displayed nothing).

But when I tested with LTIB L3.0.35,the LCD worked normally.

So could you tell me why LCD display doest not work under Yocto.

Best Regards,

ZongbiaoLiao

saurabh206 — Tue, 24 Feb 2015 04:16:57 GMT

ZongbiaoLiao

Have you tried following command after boot completed?

echo 0 > /sys/class/graphics/fb0/blank

宗標廖 — Tue, 24 Feb 2015 05:10:58 GMT

Patel

Yes,I tried that command,it did not help me.

From the L3.10.17 kernel message,I found logs about lcd as below.

mxc_sdc_fb fb.22: register mxc display driver lcd

mxc_sdc_fb fb.22: NO mxc display driver found!

But the L3.0.35 kenel just output the following log about lcd.

mxc_sdc_fb mxc_sdc_fb.0: register mxc display driver lcd

Is there anything wrong within LCD driver of Linux-imx_3.10.17?

Best Regards,

ZongbiaoLiao

宗標廖 — Wed, 25 Feb 2015 02:12:39 GMT

Patel

I have resolved the problem.

I found that the device tree for imx6 in L3.10.17 has not registered the LCD device.

After I configured the LCD for imx6 in device tree,the LCD became to work.

I attached the device tree files that I have modified.

And for my LCD display, I changed the kernel command line parameter from

video=mxcfb0:dev=lcd,CLAA-WVGA,if=RGB565 to video=mxcfb0:dev=lcd,CLAA-WVGA,if=RGB666

Best Regards,

ZongbiaoLiao

CarlosCasillas — Thu, 26 Feb 2015 01:13:38 GMT

Thanks for sharing your solution with the Community!!! :smileywink:

Best regards!
/Carlos