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Message-ID: <1495006472.30577.6.camel@suse.com>
Subject: Re: [PATCH] usb: typec: Defer checking of valid power role swap to
 low level drivers
From: Oliver Neukum <oneukum@suse.com>
To: Badhri Jagan Sridharan <badhri@google.com>,
        Heikki Krogerus <heikki.krogerus@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Guenter Roeck <linux@roeck-us.net>, linux-kernel@vger.kernel.org,
        linux-usb@vger.kernel.org
Date: Wed, 17 May 2017 09:34:32 +0200
In-Reply-To: <20170517073219.8315-1-Badhri@google.com>
References: <20170517073219.8315-1-Badhri@google.com>
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Am Mittwoch, den 17.05.2017, 00:32 -0700 schrieb Badhri Jagan
Sridharan:

Hi,

> "Two independent set of mechanisms are defined to allow a USB Type-C
> DRP to functionally swap power and data roles. When USB PD is
> supported, power and data role swapping is performed as a subsequent
> step following the initial connection process. For non-PD implementations,
> power/data role swapping can optionally be dealt with as part of the initial
> connection process."

Well, as I read it, without PD once a connection is established, you
are stuck with your role. So it seems to me that blocking a later
attempt to change it makes sense.

	Regards
		Oliver