topic MAYA W2 module Bluetooth Timeout issue in i.MX Processors

MAYA W2 module Bluetooth Timeout issue

pratham_malaviya — Thu, 29 May 2025 09:50:29 GMT

Hi there,

We are trying to bring up the IW612 based Wifi bluetooth module from MAYA with IMX8MP based board.

We were successfully able to bring-up the Wi-Fi we are having issues with bluetooth.

While the Bluetooth functionality works correctly when RTS/CTS flow control is not used, I encounter issues when enabling RTS/CTS.

Specifically, when I connect the RTS and CTS pins between the host and the module, Bluetooth initialization fails with opcode timeouts and TX errors.

root@verdin-imx8mp-15460290:~# modprobe btnxpuart [ 42.127549] wlan: SCAN COMPLETED: scanned AP count=17 root@verdin-imx8mp-15460290:~# [ 42.439851] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [ 42.445247] Bluetooth: BNEP socket layer initialized [ 43.266730] Bluetooth: hci0: FW already running. [ 45.315028] Bluetooth: hci0: Opcode 0x0c03 failed: -110 [ 47.330733] Bluetooth: hci0: Setting baudrate failed (-110) root@verdin-imx8mp-15460290:~# root@verdin-imx8mp-15460290:~# [ 49.346732] Bluetooth: hci0: Setting wake-up method failed (-110) [ 51.362750] Bluetooth: hci0: Setting Power Save mode failed (-110)

Interestingly, if I ground the CTS pin on the Bluetooth module and leave the RTS pin unconnected, the module initializes correctly and basic functionality appears to work. However, when I attempt to scan for nearby Bluetooth devices, the following errors occur:

root@verdin-imx8mp-15460290:~# hciconfig hci0: Type: Primary Bus: UART BD Address: 20:BA:36:56:BB:E0 ACL MTU: 1021:7 SCO MTU: 120:6 UP RUNNING PSCAN RX bytes:902 acl:0 sco:0 events:65 errors:0 TX bytes:1610 acl:0 sco:0 commands:64 errors:0 root@verdin-imx8mp-15460290:~# bluetoothctl hci0 new_settings: powered bondable ssp br/edr le secure-conn cis-central cis-p Agent registered [CHG] Controller 20:BA:36:56:BB:E0 Pairable: yes [bluetooth]# power on Changing power on succeeded [bluetooth]# default-agent Default agent request successful [bluetooth]# pairable on Changing pairable on succeeded [bluetooth]# scan on SetDiscoveryFilter success hci0 type 7 discovering on Discovery started [CHG] Controller 20:BA:36:56:BB:E0 Discovering: yes [bluetooth]# [ 139.054737] Bluetooth: hci0: Frame reassembly failed (-84) [NEW] Device 44:A1:70:C1:74:43 44-A1-70-C1-74-43 [bluetooth]# [ 139.836671] Bluetooth: hci0: Frame reassembly failed (-84) [ 139.842218] Bluetooth: hci0: Frame reassembly failed (-84) [CHG] Device 4F:03:41:6A:A2:92 RSSI: 0xffffffaa (-86) [bluetooth]# [ 139.985060] Bluetooth: hci0: Frame reassembly failed (-84) [NEW] Device 36:D2:3A:FC:99:05 36-D2-3A-FC-99-05 [bluetooth]# [ 140.125421] Bluetooth: hci0: Frame reassembly failed (-84) [ 140.167024] Bluetooth: hci0: Frame reassembly failed (-84) [ 140.177003] Bluetooth: hci0: Frame reassembly failed (-84)

My DTS node looks like this:

&uart1 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_uart1>; status = "okay"; assigned-clocks = <&clk IMX8MP_CLK_UART1>; assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_80M>; uart-has-rtscts; bluetooth { compatible = "nxp,88w8987-bt"; fw-init-baudrate = <115200>; status = "okay"; }; }; &iomuxc { pinctrl_uart1: uart1grp { fsl,pins = <MX8MP_IOMUXC_SAI2_RXD0__UART1_DCE_RTS 0x1c4>, /* SODIMM 135 */ <MX8MP_IOMUXC_SAI2_TXFS__UART1_DCE_CTS 0x1c4>, /* SODIMM 133 */ <MX8MP_IOMUXC_UART1_RXD__UART1_DCE_RX 0x1c4>, /* SODIMM 129 */ <MX8MP_IOMUXC_UART1_TXD__UART1_DCE_TX 0x1c4>; /* SODIMM 131 */ }; };

My hardware connection are as follows:

HOST SIDE (IMX8MP) MODULE SIDE (MAYA W2)

UART1_TX	UART_RX
UART1_RX	UART_TX
UART1_CTS	UART_RTS
UART1_RTS	UART_CTS

I have also tried reversing the RTS and CTS connections, but there was no change in behaviour.

What could be causing this failure when RTS/CTS is enabled?
What configuration or hardware checks would you recommend to ensure proper RTS/CTS operation?

Re: MAYA W2 module Bluetooth Timeout issue

Chavira — Thu, 29 May 2025 16:17:06 GMT

HI @pratham_malaviya!

Thank you for contacting NXP Support!

What BSP version are you using?

Can you try using the next values?

pinctrl_uart1: uart1grp { fsl,pins = <MX8MP_IOMUXC_SAI2_RXD0__UART1_DCE_RTS 0x140>, /* SODIMM 135 */ <MX8MP_IOMUXC_SAI2_TXFS__UART1_DCE_CTS 0x140>, /* SODIMM 133 */ <MX8MP_IOMUXC_UART1_RXD__UART1_DCE_RX 0x140>, /* SODIMM 129 */ <MX8MP_IOMUXC_UART1_TXD__UART1_DCE_TX 0x140>; /* SODIMM 131 */ };

Remember that you have to install the wifi (modprobe moal mod_para=nxp/wifi_mod_para.conf) drivers before to insert the btnxpuart module.

Best Regards!

Chavira

Re: MAYA W2 module Bluetooth Timeout issue

pratham_malaviya — Fri, 30 May 2025 07:37:55 GMT

Hi @Chavira ,

Thanks for your response,

What BSP version are you using?

--I am using linux kernel version 6.6.74.

Can you try using the next values?

-- I have tried this but i am having the same OP code failure error.

Error log:

root@verdin-imx8mp-15460290:~# modprobe btnxpuart [ 38.966015] wlan: SCAN COMPLETED: scanned AP count=8 [ 38.980544] wlan: mlan0 START SCAN root@verdin-imx8mp-15460290:~# [ 40.376824] Bluetooth: BNEP (Ethernet Emulation) ver 1.3 [ 40.382218] Bluetooth: BNEP socket layer initialized [ 41.186982] Bluetooth: hci0: FW already running. [ 43.234989] Bluetooth: hci0: Opcode 0x0c03 failed: -110 [ 44.843967] wlan: SCAN COMPLETED: scanned AP count=12 [ 45.250972] Bluetooth: hci0: Setting baudrate failed (-110) [ 47.267007] Bluetooth: hci0: Setting wake-up method failed (-110) [ 49.282970] Bluetooth: hci0: Setting Power Save mode failed (-110)

Re: MAYA W2 module Bluetooth Timeout issue

DanielRuvalcaba — Fri, 30 May 2025 17:12:30 GMT

Hi,

The NXP Bluetooth Serial driver can run standalone, so it is OK to only issue modprobe btnxpuart.

1. I assume you are using a custom board based on the iMX8MP, can you confirm?
2. Could you please try with fw-init-baudrate=3000000 (just because this is the one I tried)?
4. Are you able to see with an external device like a logic analyzer the RTS and CTS communication?
5. I did a test on my side using the iMX8MP-EVK and the 2EL module, and it is working on my side. I just changed the default dtb. You can take a look to the one I used in the iMX8MP BSP.

Regards,

Daniel.