I am using application uart of iMX287. I am using AUART2 on the same.
Initially to test AUART I did echo "Hello World" /dev/ttySP2.
This ended with some error/warning "Usage: mxmxs-auart mxs-auart.2: Unhandled status 52028d".
On forum I came to know about this could be some parity or framing error. I am not sure how simple echo can lead to such kind of errors.
Then I tested one of my working program (tested one on iMX233) with the iMX287 board that also lead to same error/warning. In that code I have used no parity.
Later I enable DMA for this AUART and compiled linux kernel (18.104.22.168) and tested the code. After enabling DMA I haven't seen any "Usage: mxmxs-auart mxs-auart.2: Unhandled status 52028d".
But I am not able to see any data over wire. I tested minicom with and without DMA. With minicom I was not able to see any data over TX/RX lines.
Unfortunately "cat /proc/tty/driver/auart" show TX/RX count to be zero. Someone on forum has mentioned that those counters are disable for security reasons.
Has anyone faced such kind of issue?