Not support Raspberry LCD 7 Inch 800*480

[doquanghuyit]

Hi, I have tried make a test on Raspberry 3 B+.
The problem is I can't set the solution down to 800*400 when I tried replace in file "cmdline.txt" by line drm_kms_helper.edid_firmware=edid/1280x720.bin
it's only accept minimum 800x600, so I guest the kernel is not support this resolution.
So hope you can update this kernel to working with resolution.
Thanks & Best Regards.
Do Quang Huy

[dieseltronic]

Hi,
we need more infos about the display... type ?

The goal is to get displays edid data.
Under Raspbian run sudo /opt/vc/bin/tvservice -d hdmi-800x480.bin to get edid data.
tcservice will create the file hdmi-800x480.bin. This file contains displays edid data.

Now copy that file into $ANDROIDSOURCE/kernel-v4.14/firmware/edid/ folder.

Build new Kernel with: CONFIG_EXTRA_FIRMWARE="brcm/brcmfmac43430-sdio.bin brcm/brcmfmac43430-sdio.txt brcm/brcmfmac43455-sdio.clm_blob brcm/brcmfmac43455-sdio.txt brcm/brcmfmac43455-sdio.bin edid/hdmi-800x400.bin"

In cmdline.txt change to: drm_kms_helper.edid_firmware=edid/hdmi-800x480.bin

Tested by myself with succes for this device: https://www.ebay.de/itm/Raspberry-Pi-5-inch-LCD-Touchscreen-TFT-HDMI-800x480-RPI-Display-with-stylus/283412360350?hash=item41fcb16c9e:g:dvcAAOSweGpchY4P
TFP401x TI PanelBus™ Digital Receiver: http://www.ti.com/lit/ds/symlink/tfp401a.pdf
Touchscreen controller: XPT2046 / (ads7846)

I can provide for this display edid data.
Perhaps Mr.Brobwind can add the edid file and changes into his repository so we can find a way
to support different dilspays? ;-)

Do you have touchscreen working?
Which touchcontroller do you have on your display?

[doquanghuyit]

Thanks for your answer.
I believe your solution would be work. I'll test and make a confirm to you.
I'm using a lcd 7 inch communicate via HDMI and support touching over USB also.
this is link's product
http://www.lcdwiki.com/7inch_HDMI_Display-B
Touching is worked already by default HID USB. it only work not correct by wrong resolution.

[brobwind]

@dieseltronic Thank!
Currently, only kernel built-in edid data and 720p edid as I added in the kernel firmware.
The kernel request edid data too much early (before mount the vendor partition), I can not place the edid data on the vendor partion.
Need to find a way to solve this.

[doquanghuyit]

I confirmed the dieseltronic's solution is worked !
But the device have to wait 2 3 minutes for boot to animation.