DM368 usb OTG 模式host与device 切换问题..

https://e2e.ti.com/support/embedded/int-embedded_software/int-linux/f/118/t/56502

As you rightly pointed out, USB-Host and USB-OTG are supported on DM36x hardware as well as linux driver. But DM365/DM368 IP Camera Reference Design does not have support for USB host mode. For the USB host operations, we need to have ID pin pulled to low and a charge pump to drive 5V on the USB_VBUS signal. The hardware currently does not support this.

The change that needs to be done in kernel config is as below:

CONFIG_USB_MUSB_HOST=y
CONFIG_USB_MUSB_OTG=y

For the hardware changes, i can suggest a few options and you can evaluate if it helps your customer:

1. Remove the resistor R34 and connect USB_ID pin to USB_GND. This will be a blue wiring on the man board of IPNC

2. For charge pump, there will be lot more work to add it on the board. One option is to connect a USB device which is self-powered and drive 5V on the VBus signal of that device directly, all the time. This way IPNC does not have to drive VBus.

The above two options can help you make it work as host, but surely not as OTG device. For OTG device, there is a lot more functionality required in the chargepump and controlling the voltage on the USB_VBUS.

HI,

1.DM368的电路板我是自己重新做的板子..所以关于移除R34 不是很明白..

2.如果DM368 做HOST, u盘做device , USB_VBUS是否会自动输出5v 给USB 供电..

hi, Eason,

但是我的内核2.6.37版本不能同时配置

CONFIG_USB_MUSB_HOST=y
CONFIG_USB_MUSB_OTG=y

两者只能取其一..