LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Heikki Krogerus <heikki.krogerus@linux.intel.com>
To: Felipe Balbi <balbi@kernel.org>
Cc: Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@amd.com>,
	gregkh@linuxfoundation.org, linux-usb@vger.kernel.org,
	linux-kernel@vger.kernel.org, kun.liu2@amd.com,
	alexander.deucher@amd.com
Subject: Re: [RESEND PATCH 2/2] usb: dwc3: pci add property to allow user space role switch
Date: Wed, 25 Aug 2021 10:01:05 +0300	[thread overview]
Message-ID: <YSXqsXmuom2fFiKN@kuha.fi.intel.com> (raw)
In-Reply-To: <87ilzu5ap0.fsf@kernel.org>

On Wed, Aug 25, 2021 at 08:55:41AM +0300, Felipe Balbi wrote:
> 
> Hi,
> 
> Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@amd.com> writes:
> 
> > For AMD platform there is a requirement to enable user space role
> > switch from host to device and device to host as customer platform is not
> > completely capable of OTG i.e. with type C controller it does not have PD
> > to support role switching. Hence, based ACPI/EC interrupt role switch is
> > triggered by the usemode script running in background.
>                    usermode ?

Couldn't you capture that ACPI/EC interrupt in kernel?

> > Signed-off-by: Nehal Bakulchandra Shah <Nehal-Bakulchandra.shah@amd.com>
> 
> I'm okay with this, just wondering if we need to Document the property
> somewhere.
> 
> @Heikki, is there a place to document these private properties that's
> not on DT binding document?

The build-in properties are not documented separately. I've always
tried to supply DT bindings for all new properties I've proposed.

In this case though, do we need the new property at all? Why not just
register a normal USB role switch on this platform? It can be either a
dummy role switch that only passes the user space input to dwc3, or,
perhaps ideally, it would also be a driver that captures that ACPI/EC
event/notification and then passes the information from it to dwc3.

thanks,

-- 
heikki

  reply	other threads:[~2021-08-25  7:01 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-24 19:23 Nehal Bakulchandra Shah
2021-08-25  5:55 ` Felipe Balbi
2021-08-25  7:01   ` Heikki Krogerus [this message]
2021-08-25  7:26     ` Heikki Krogerus
2021-08-25 13:50       ` Deucher, Alexander
2021-08-26 14:06         ` Heikki Krogerus
2021-09-02 12:45           ` Shah, Nehal-bakulchandra
2021-09-09 12:55             ` Heikki Krogerus
2021-08-25  7:43     ` Felipe Balbi
2021-08-26 11:13 ` Greg KH

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=YSXqsXmuom2fFiKN@kuha.fi.intel.com \
    --to=heikki.krogerus@linux.intel.com \
    --cc=Nehal-Bakulchandra.shah@amd.com \
    --cc=alexander.deucher@amd.com \
    --cc=balbi@kernel.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=kun.liu2@amd.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --subject='Re: [RESEND PATCH 2/2] usb: dwc3: pci add property to allow user space role switch' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).