RT105x USB BC support

[mateuszpiesta]

Hello,

We are designing custom device based on RT1051 uC which is battery powered. We need to have option for charging it trough USB Type-C connector. We are using external chip for Type-C support but we are also need to distinguish between dedicated/host chargers. We found that USB-PHY supports BC standard. Does NXP USB stack support BC ? 

There is USB_DEVICE_CHARGER_DETECT_ENABLE flag defined which suggests that such support is provided. After some digging in sources we also found that it needs FSL_FEATURE_SOC_USBDCD_COUNT set to compile. Unfortunately this flag is not defined in MIMXRT1051_features.h. Does that mean that RT1050 doesn't support BC or maybe USB stack is not yet prepared for BC support on RT1051 ?

Could you shed some light on this issue ?

Best regards

Mateusz Piesta

[jorge_a_vazquez]

Hi Mateusz Piesta

or maybe USB stack is not yet prepared for BC support on RT1051 ?

USBDCD is not in RT1050, this is why the FSL_FEATURE_SOC_USBDCD_COUNT is cero, in the RT1050 devices you can find the USB_ANALOG in the USB-PHY part.

This Phy is capable of the charger detection which "detects whether the upstream-facing device is connected to a down-stream facing charger, either a dedicated USB charger or a host charger". Unfortunately, this is not implemented in the usb_phy.c file of the USB stack, so the customer would need to add it.

Hope this helps.

Best regards