Revision as of 02:50, 11 October 2017

References

source code

device-tree document

Tips

Whether LVDS display card has been registered successfully

If the LVDS display card has been created, it would create a sysfs debug directory.

<code>$ ls /sys/class/drm/card0-LVDS-1</code>

So you just need to check that directory. If that directory is missing in your machine board, please check:

• Whether LVDS have been enabled in DTS files.
• Whether LVDS panel have been registered successfully.
• Whether you have available VOP module for LVDS.
• Check the kernel log for more detail (dmesg | grep lvds)

Check LVDS display card status: status, enabled, modes

<code>$ cd /sys/class/drm/card0-LVDS-1
$ cat status  # should printed "connected" or "disconnected"
$ cat enabled # should printed "enabled" or "disabled"
$ cat modes   # should printed the available mode list, like 1536x2048</code>

If you still have no picture on LVDS panel, please check bellow information:

• Check the LVDS panel power supply.
• Check the panel datasheet, ensure you have configured the timing and data format rightly.
• Check the hardware connected status, or test the panel on workable board.