Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20220314195458.271430-1-wonchung@google.com> <CAOvb9yguWiJgeYBb1eTnAUpNQ-f5f-tQDnDNw+XzBXRx0H156g@mail.gmail.com>
 <YjrKYcta2SUjn3Pk@kroah.com>
In-Reply-To: <YjrKYcta2SUjn3Pk@kroah.com>
From:   Won Chung <wonchung@google.com>
Date:   Wed, 23 Mar 2022 10:54:44 -0700
Message-ID: <CAOvb9yi_YYVjT1ZVKE0oOH8GeqgqbDkcsNC2WMwUJFw6J37-OQ@mail.gmail.com>
Subject: Re: [PATCH v6] driver core: Add sysfs support for physical location
 of a device
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Heikki Krogerus <heikki.krogerus@linux.intel.com>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        Benson Leung <bleung@chromium.org>,
        Prashant Malani <pmalani@chromium.org>,
        linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Wed, Mar 23, 2022 at 12:21 AM Greg Kroah-Hartman
<gregkh@linuxfoundation.org> wrote:
>
> On Tue, Mar 22, 2022 at 09:36:02AM -0700, Won Chung wrote:
> > On Mon, Mar 14, 2022 at 12:55 PM Won Chung <wonchung@google.com> wrote:
> > I am sorry to keep bothering you with this, but can you take a look at
> > this patch for a review when you have time? Thank you very much!
>
> It is the middle of the merge window now, and I will look at this after
> 5.18-rc1 is out.  Due to all of the constant churn in this (and you only
> fixing the memory leak in the last submission), I had put this on the
> bottom of my review queue.
>
> Also, I don't see an actual user of these new attributes anywhere, so
> even if this was accepted, who is going to use it?
>
> thanks,
>
> greg k-h

Hi Greg,

Thank you for the information.

As a start, we are planning to use this in Chrome OS to specify the
physical location of each USB device since Coreboot adds _PLD fields
to usb port and typec connector. Currently, if there is one USB device
connected on the left panel and another USB device connected on the
right panel, the userspace cannot distinguish which device is on the
left or the right panel. Once each USB device exposes its location
info, we can gather more data on users' preference on port usage.
Also, it can apply to not just USB devices, but also other types like
HDMI ports in the future.
Would this answer your question?


Hey Benson, can you take a look at this if I am not mistaken or
missing some details?


Thanks,
Won