iMX8QXP - How to enable 32.768KHz clock output on SCU_BOOT_MODE3 pin

[Buridan]

Hi NXP:

I'm using USDHC1 for WIFI/BT module interface, and the module need a 32.768KHz clock as the RTC clock. The hardware designed about module clock as the the develop demo board, so I need the 32.768KHz clock outputed from the SOC but it seems doesn't work. The dts configures as fllow:

bcmdhd_wlan_0: bcmdhd_wlan@0 {
	compatible = "android,bcmdhd_wlan";
	pinctrl-names = "init", "idle", "default";
	pinctrl-0 = <&pinctrl_wifi_init>;
	pinctrl-1 = <&pinctrl_wifi_init>;
	pinctrl-2 = <&pinctrl_wifi>;
	...
	status = "okay";
};
pinctrl_wifi: wifigrp{
	fsl,pins = <
		IMX8QXP_SCU_BOOT_MODE3_SCU_DSC_RTC_CLOCK_OUTPUT_32K	0x20
	>;
};

pinctrl_wifi_init: wifi_initgrp{
	fsl,pins = <
		/* reserve pin init/idle_state to support multiple wlan cards */
	>;
};

So, what else should I do for output? 

[igorpadykov · Accepted solution]

Hi Buridan

one can check for CONFIG_BRCMFMAC=m in linux defconfig

just for test set all pinctrl = <&pinctrl_wifi>;

Best regards
igor

[Buridan]

Hi igorpadykov:

    Thanks fo your help and I get the output now. The reason of this problem may because the module driver did not installed correctly.