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Date:   Mon, 4 Dec 2023 18:27:40 -0800
From:   Jakub Kicinski <kuba@kernel.org>
To:     Douglas Anderson <dianders@chromium.org>
Cc:     linux-usb@vger.kernel.org,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "David S . Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>,
        Grant Grundler <grundler@chromium.org>,
        Hayes Wang <hayeswang@realtek.com>,
        Simon Horman <horms@kernel.org>,
        =?UTF-8?B?QmrDuHJu?= Mork <bjorn@mork.no>,
        netdev@vger.kernel.org, Brian Geffon <bgeffon@google.com>,
        Alan Stern <stern@rowland.harvard.edu>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH net v2 3/3] r8152: Choose our USB config with
 choose_configuration() rather than probe()
Message-ID: <20231204182740.62a49a14@kernel.org>
In-Reply-To: <20231201102946.v2.3.Ie00e07f07f87149c9ce0b27ae4e26991d307e14b@changeid>
References: <20231201183113.343256-1-dianders@chromium.org>
        <20231201102946.v2.3.Ie00e07f07f87149c9ce0b27ae4e26991d307e14b@changeid>
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Precedence: bulk

On Fri,  1 Dec 2023 10:29:52 -0800 Douglas Anderson wrote:
> If you deauthorize the r8152 device (by writing 0 to the "authorized"
> field in sysfs) and then reauthorize it (by writing a 1) then it no
> longer works. This is because when you do the above we lose the
> special configuration that we set in rtl8152_cfgselector_probe().
> Deauthorizing causes the config to be set to -1 and then reauthorizing
> runs the default logic for choosing the best config.
> 
> I made an attempt to fix it so that the config is kept across
> deauthorizing / reauthorizing [1] but it was a bit ugly.
> 
> Let's instead use the new USB core feature to override
> choose_configuration().
> 
> This patch relies upon the patches ("usb: core: Don't force USB
> generic_subclass drivers to define probe()") and ("usb: core: Allow
> subclassed USB drivers to override usb_choose_configuration()")

Acked-by: Jakub Kicinski <kuba@kernel.org>