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Date:   Thu, 03 Sep 2020 08:40:34 +0200
Message-ID: <s5h5z8v8isd.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Alan Stern <stern@rowland.harvard.edu>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        himadrispandya@gmail.com, dvyukov@google.com,
        linux-usb@vger.kernel.org, perex@perex.cz, tiwai@suse.com,
        linux-kernel@vger.kernel.org, marcel@holtmann.org,
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        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
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        Dmitry Panchenko <dmitry@d-systems.ee>,
        Chris Wulff <crwulff@gmail.com>,
        Jesus Ramos <jesus-ramos@live.com>
Subject: Re: [PATCH 01/10] USB: move snd_usb_pipe_sanity_check into the USB core
In-Reply-To: <20200903004553.GA642955@rowland.harvard.edu>
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        <20200902110115.1994491-2-gregkh@linuxfoundation.org>
        <20200903004553.GA642955@rowland.harvard.edu>
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On Thu, 03 Sep 2020 02:45:53 +0200,
Alan Stern wrote:
> 
> In a few places here this check is completely unnecessary.  All it does 
> is verify that the device does have an endpoint 0 and the the type of 
> the endpoint matches the type of the pipe.  Well, every USB device 
> always has an endpoint 0, and it is always a bidirectional control 
> endpoint.  Therefore a simple static check is all you need: There's no 
> point calling usb_pipe_type_check() when the pipe is of the form 
> usb_{snd|rcv}ctrlpipe(dev, 0).
> 
> In short, this check should be removed completely; it does nothing.

Fair enough, but I think those removals should be in another patch.


thanks,

Takashi