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Date:   Wed, 16 Feb 2022 11:36:32 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     3090101217@zju.edu.cn
Cc:     balbi@kernel.org, ruslan.bilovol@gmail.com,
        pavel.hofman@ivitera.com, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org, Jing Leng <jleng@ambarella.com>
Subject: Re: [PATCH] usb: gadget: f_uac1: add set requests support
Message-ID: <YgzTsLV/nSKp7FWP@kroah.com>
References: <20220216094301.2448-1-3090101217@zju.edu.cn>
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On Wed, Feb 16, 2022 at 05:43:01PM +0800, 3090101217@zju.edu.cn wrote:
> From: Jing Leng <jleng@ambarella.com>
> 
> Currently the f_uac1 driver only supports UAC_SET_CUR request.
> 
> But when uac1 device is plugged to Ubuntu 20.04 PC, at the stage
> of setup, the PC will send UAC_SET_RES request, If the device
> doesn't respond to the request, the PC will abort the setup process
> and uac1 device can't be recognized on Ubuntu 20.04 PC.

So is this a bug in the Host side to not do stuff like this?  Why not
fix it there instead?

Where is the requirement that this command must be handled by the
device?

thanks,

greg k-h