Re: [PATCH 4/9] usb: gadget: udc: renesas_usb3: use extcon framework to receive connect/disconnect

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Wed, Mar 06, 2019 at 09:07:21AM +0000, Biju Das wrote:
> RZ/G2E cat874 board is capable of detecting cable connect and disconnect
> events. Add support for renesas_usb3 to receive connect and disconnect
> notification using extcon framework.

I think you will need the series from Yu Chen [1], but once we have
that, you can do this with USB role class instead of relying on
extcon, and that is what you need to do.

There is a reason why we need to use a dedicated class with the USB
role switching instead of relying on extcon. We actually originally
planned on using extcon with the USB role switches, but the extcon
maintainers refused some the USB mux drivers. The problem from extcon
perspective is that the consumer/supplier roles seem to be inverted in
some cases. USB role switch can simply be too many things - discrete
mux, integrated mux (like in your case) or something like a dual role
capable USB controller could simply represent one.

On the other hand, using a dedicated API and class now feel like a
much better idea in general compared to a multipurpose thing like
extcon.

[1] https://lkml.org/lkml/2019/3/2/42

thanks,

-- 
heikki



[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux