Change Bluetooth Output Transmit Power Level on Apalis iMX6

I am trying to control transmit power level of a Bluetooth module (PAN1326B) with imx.6 connected over UART using hciconfigtool.

The exact command that i am using is as hciconfig hci0 inqtpl <level>.After executing the command if I check the module power level using hciconfig hci0 inqtpl , it shows the same value as it was before running the command (Transmit Power level 12). Is there anything wrong in the way the level is being changed. Are there any other ways to change transmit power level of a BT module with linux hosts over hci.
My BT module is a class 1 device and has transmit power level control available.

The code used to enable Bluetooth module is

root@apalis-imx6:~# hciattach /dev/ttymxc1 texas
Found a Texas Instruments' chip!
Firmware file : /lib/firmware/ti-connectivity/TIInit_6.7.16.bts
Loaded BTS script version 1
texas: changing baud rate to 115200, flow control to 1
[ 1582.117152] Bluetooth: HCI UART driver ver 2.2
[ 1582.121638] Bluetooth: HCILL protocol initialized
[ 1582.443282] Bluetooth: RFCOMM TTY layer initialized
[ 1582.448298] Bluetooth: RFCOMM socket layer initialized
[ 1582.453543] Bluetooth: RFCOMM ver 1.11
Device setup complete

root@apalis-imx6:~# bluetoothctl -a
[NEW] Controller B0:B4:48:6C:8F:43 apalis-imx6 [default]
Agent registered
[bluetooth]# default-agent on
Default agent request successful

I am not familiar with the PAN1326B. I guess it could be that the module or/and the driver does not support transmit power configuration. Do you get a different behavior on a x86 machine? Did you tried to contact support of the Bluetooth module provider?

The module is capable of output power control. I could not test it on any other machine because i do not have level transceivers.
I have contacted the Bluetooth module manufacturer but no response yet, but I am sure the module is class 1 and has capability of transmit power level control.

Is there any way of controlling(read/write) register values of imx6 using a linux OS. I have read the datasheet of i.mx6 at register level but linux OS gives very superficial level of control. What are the ways in which I can control register level things. Being an hardware engineer I do not have experience in OS drivers.