From: Rob Herring <robh@kernel.org>
To: "David R. Piegdon" <lkml@p23q.org>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>,
Alan Stern <stern@rowland.harvard.edu>,
Chunfeng Yun <chunfeng.yun@mediatek.com>,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Johan Hovold <johan@kernel.org>, Kay Sievers <kay@vrfy.org>,
Mark Rutland <mark.rutland@arm.com>,
Martin Blumenstingl <martin.blumenstingl@googlemail.com>,
Mathias Nyman <mathias.nyman@linux.intel.com>,
Roger Quadros <rogerq@ti.com>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-usb@vger.kernel.org, systemd-devel@lists.freedesktop.org
Subject: Re: [RFC PATCH 0/2] USB: DTS: allow suggesting busnumber for platform USB bus via DTS alias
Date: Tue, 11 Dec 2018 16:42:42 -0600 [thread overview]
Message-ID: <20181211224242.GA21950@bogus> (raw)
In-Reply-To: <20181127165705.GA13460@lagavulin.indurad.x>
On Tue, Nov 27, 2018 at 04:57:05PM +0000, David R. Piegdon wrote:
> Hi,
>
> on our embedded systems we rely on systemd's persistent netdev names.
> Those currently do not work for USB netdevs that are connected to a
> platform USB bus.
>
> In https://github.com/systemd/systemd/pull/7273 a systemd patch was
> suggested that would allow exactly this, but it was (rightfully) said
> that numbering of theses busses is not guaranteed. Internally we used
> the patch for a while now, but exactly that has happened with one of our
> platforms across different kernel revisions.
>
> The following kernel patches allow suggesting a USB busnumber for each
> USB platform bus via a DTS alias, as can be done similarly for many
> other devices.
> In combination with above systemd patch, these changes allow use of
> persistent netdev names also on platform USB busses.
I don't think this is doing what was suggested in the link above. Though
I'm not familiar with what ACPI provides. Userspace would still be
relying on the Linux enumeration numbering. How would userspace tell if
that numbering is persistent or not other than looking at the DT itself
(which isn't a good solution either)?
I don't understand though why userspace needs anything more that the mac
address of a net device to provide a persistent name.
Rob
prev parent reply other threads:[~2018-12-11 22:42 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-27 16:57 [RFC PATCH 0/2] USB: DTS: allow suggesting busnumber for platform USB bus via DTS alias David R. Piegdon
2018-12-11 22:42 ` Rob Herring [this message]
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=20181211224242.GA21950@bogus \
--to=robh@kernel.org \
--cc=bigeasy@linutronix.de \
--cc=chunfeng.yun@mediatek.com \
--cc=devicetree@vger.kernel.org \
--cc=gregkh@linuxfoundation.org \
--cc=gustavo@embeddedor.com \
--cc=johan@kernel.org \
--cc=kay@vrfy.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=lkml@p23q.org \
--cc=mark.rutland@arm.com \
--cc=martin.blumenstingl@googlemail.com \
--cc=mathias.nyman@linux.intel.com \
--cc=rogerq@ti.com \
--cc=stern@rowland.harvard.edu \
--cc=systemd-devel@lists.freedesktop.org \
/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
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
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).