An error occurs when writing to UART

1

I am using WP7605. The OS versions are as follows:

  • Legato Version: 21.05.2.rc2

  • Yocto Version: SWI9X07Y_03.01.07.00

  • OS Version: Linux version 4.14.253

  • LK Version: SWI9X07Y_03.01.07.0

When I executed the write command on the UART, the following error occurred.
Please tell me the cause and how to resolve it.

[ 610.050803] msm_hs_set_mctrl_locked: UART 0, mctrl=0x0000, set_dcd=1, set_dsr=1, set_ri=1 (0 is ON, 1 is OFF)
INFO | supervisor[1230]/supervisor T=main | proc.c proc_SigChildHandler() 2094 | Process ‘mobileStation’ (PID: 1403) has exited with exit code 1.

2

You can refer to this application: