K2G SDK does not support LED screen drivers

user4820138

Hi,

I would like to use # K2G GENERAL PURPOSE EVM REV.D # Run MiniGUI/QT applications, but I installed a 4.3-inch led screen that linux can not drive LED screen. I did not find in the linux kernel and screen-driven part of the relevant. Is not now the K2G SDK does not support LED screen drivers?

over 7 years ago

0 Cvetolin Shulev-XID over 7 years ago

TI__Guru 65405 points

Hello,

Could you specify which SDK and kernel version you are using?

BR
Tsvetolin Shulev

0 user4820138 over 7 years ago in reply to Cvetolin Shulev-XID

Prodigy 70 points

software-dl.ti.com/.../index_FDS.html

I use the SDK to create ROOTFS, boot with an SD card. After the boot test the LED backlight voltage 11V, the boost PWM is not working.

0 Cvetolin Shulev-XID over 7 years ago in reply to user4820138

TI__Guru 65405 points

I suggest you to check weather the PWM driver is enabled in your kernel config. You can find detailed description in the linked below Linux Core PWM User's Guide:
processors.wiki.ti.com/.../Linux_Core_PWM_User's_Guide
leds-pwm.c is a PWM driver:
lxr.free-electrons.com/.../leds-pwm.c
You can find weather presents leds-pwm.o file after building your Linux kernel.
Also Pulse Width Modulation (PWM) interface Linux kernel documentation would be useful:
www.kernel.org/.../pwm.txt

BR
Tsvetolin Shulev

0 user4820138 over 7 years ago in reply to Cvetolin Shulev-XID

Prodigy 70 points

I from the kernel of the arch/arm/boot/DTS/keystone - k2g. Dtsi not found related to the PWM interface description, so even configuring the kernel to add PWM drive doesn't work.
The question now is I feel the SDK contains the content of incomplete, because I didn't find the following description of the resources.

--------------------------------
Features

Linux features

Open Linux support
Linux kernel and Bootloaders
File system
Qt/Webkit application framework
3D graphics support
Integrated WLAN and Bluetooth® support
GUI-based application launcher
Example applications, including:
ARM benchmarks: Dhrystone, Linpack, Whetstone
Webkit web browser
Soft Wifi access point
Cryptography: AES, 3DES, MD5, SHA
Multimedia: GStreamer/FFMPEG
Programmable Realtime Unit (PRU)
Code Composer Studio™ IDE for Linux development
Documentation

0 Cvetolin Shulev-XID over 7 years ago in reply to user4820138

TI__Guru 65405 points

The Linux kernel documentation gives a device tree example for PWM:
www.kernel.org/.../pwm.txt
Compare your PWM device tree configuration with linked.

BR
Tsvetolin Shulev

0 user4820138 over 7 years ago in reply to Cvetolin Shulev-XID

Prodigy 70 points

Thank you, we have been able to get the output of HDMI, but we want to let the DSS signal output to LCD screen, how can we configure or modify the kernel. Such as adjusting the pixel clock parameters. How to register configuration.

0 Cvetolin Shulev-XID over 7 years ago in reply to user4820138

TI__Guru 65405 points

The first step is to check weather the DSS driver is enabled as it is described in the Linux Core DSS guide at:
processors.wiki.ti.com/.../Linux_Core_DSS_User's_Guide
but seems it has been done because you have output on HDMI.
Check in the menuconfig if there is something missing related to the LCD:
-> Device Drivers
-> Graphics support
-> OMAP2+ Display Subsystem support (OMAP2_DSS [=y])
-> OMAP2/3 Display Device Drivers
Check in the device tree weather presents configuration of the LCD display and timings are correct. You can find an example in the Lernel/Documentation/devicetree/bindings/display/tilcdc/panel.txt
At the final step check the u-boot bootargs display configuration.

BR
Tsvetolin Shulev

0 user4820138 over 7 years ago in reply to Cvetolin Shulev-XID

Prodigy 70 points

Can not find the OMAP2_DSS option in menuconfig
So I think SDK K2G is not completely

Processors

Processors forum

K2G SDK does not support LED screen drivers