i.MX 8M Mini USB OTG

キャンセル
次の結果を表示 
表示  限定  | 次の代わりに検索 
もしかして: 

i.MX 8M Mini USB OTG

1,429件の閲覧回数
xiaobao
Contributor I

Want the USB OTG port on the IMX8 to connect only at low speed.  What's the best way to do that?

0 件の賞賛
返信
4 返答(返信)

1,425件の閲覧回数
igorpadykov
NXP Employee
NXP Employee

Hi Xianbao

 

usb speed is detected automatically during enumeration (state of D+/D- lines), for details one can refer to

usb2.0 specification or simple description on

https://www.beyondlogic.org/usbnutshell/usb2.shtml

 

Best regards
igor

0 件の賞賛
返信

1,410件の閲覧回数
xiaobao
Contributor I

Hi Igor

I know usb speed is detected automatically during enumeration (state of D+/D- lines).

I see in the IMX8 datasheet(USBx_nPORTSC1 register bit of PFSC ) and the Chipidea /core.c:654 driver file that the configuration port is supported only at full speed connection.But,I don't see information in the IMX8 USB register instructions about configuring only low speed connections. 2.png

1.png

Does USB OTG support driver configuration to connect only at low speeds?  

Best regards

xianbao

0 件の賞賛
返信

1,407件の閲覧回数
igorpadykov
NXP Employee
NXP Employee

>Does USB OTG support driver configuration to connect only at low speeds?

 

I am afraid not, sorry.

 

Best regards
igor

0 件の賞賛
返信

1,402件の閲覧回数
xiaobao
Contributor I

Thank you very much for your answer,Maybe I made a mistake.

On other platforms, USB speed can be limited by the “maximum-speed” attribute of the USB device tree node, but no configuration logic for USB speed is found in the IMX8USBOTG driver.  Can I limit the USB speed to low-speed through the driver?  If so, how to configure it?  

 

Best regards

xianbao

0 件の賞賛
返信