Serial Port Read failed but tx/rx increased in /proc/tty/driver/serial

I have been working on serial port of one embedded linux device. We are managing one controller using serial port.

Here is my Serial port settings

Baudrate:9600

tio.c_cflag = BAUDRATE | CS8 | CLOCAL | CREAD | CRTSCTS;

tio.c_iflag = IGNPAR;

tio.c_oflag = 0;

tio.c_lflag = 0;

tio.c_cc[VTIME] = 0;

tio.c_cc[VMIN] = 1;

Here is the data I am writing on Serial port

FEFF2801008120002100001100000000000000000000000000 00000000000000000000000000000000FCEF

If the controller received above data correctly than it should return "feff0520000227ef".

It returns 8 bytes when we write the 43 bytes.

Here is the output of tx/rx

root@5_15_60_0:~# cat /proc/tty/driver/serial

serinfo:1.0 driver revision:

0: uart:16550A mmio:0x18020000 irq:11 tx:257 rx:29 brk:6 RTS|CTS|DTR|DSR|CD

root@5_15_60_0:~# cat /proc/tty/driver/serial

serinfo:1.0 driver revision:

0: uart:16550A mmio:0x18020000 irq:11 tx:300 rx:37 brk:6 RTS|CTS|DTR|DSR|CD

root@5_15_60_0:~# cat /proc/tty/driver/serial

serinfo:1.0 driver revision:

0: uart:16550A mmio:0x18020000 irq:11 tx:343 rx:45 brk:6 RTS|CTS|DTR|DSR|CD

root@5_15_60_0:~# cat /proc/tty/driver/serial

serinfo:1.0 driver revision:

0: uart:16550A mmio:0x18020000 irq:11 tx:386 rx:53 brk:6 RTS|CTS|DTR|DSR|CD

It says 0 bytes in input buffer when run IOCTL command FIONREAD but I can see the value of tx and rx values are increasing as expected. Also unable to read the bytes.

I have removed following line from /etc/inittab file

ttyS0::askfirst:/bin/ash --login

Also removed the console=ttyS0 from bootargs.

So anyone please guide me to resolve the same? Can anyone point out the something to resolve this issue?

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