Thanks for your reply.
I tried to change the lcd display mode on imx6q-sdb using xrandr command.
But it is not working well and the command prints a error message.
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$ xrandr -o left
X Error of failed request: BadMatch (invalid parameter attributes)
Major opcode of failed request: 150 (RANDR)
Minor opcode of failed request: 2 (RRSetScreenConfig)
Serial number of failed request: 14
Current serial number in output stream: 14
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If you know how to solve this problem, please let me know it.