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Date:   Mon, 6 Sep 2021 23:05:46 -0700
From:   Dmitry Torokhov <dmitry.torokhov@gmail.com>
To:     "Tobita, Tatsunosuke" <tatsunosuke.tobita@wacom.com>
Cc:     Alistair Francis <alistair@alistair23.me>,
        "Cheng, Ping" <Ping.Cheng@wacom.com>,
        "linux-input@vger.kernel.org" <linux-input@vger.kernel.org>,
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        "kernel@pengutronix.de" <kernel@pengutronix.de>,
        "pinglinux@gmail.com" <pinglinux@gmail.com>,
        "junkpainting@gmail.com" <junkpainting@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "alistair23@gmail.com" <alistair23@gmail.com>,
        "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>
Subject: Re: [PATCH v10 05/12] Input: wacom_i2c - Read the descriptor values
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Hi Tatsunosuke,

On Thu, Sep 02, 2021 at 07:33:49AM +0000, Tobita, Tatsunosuke wrote:
> Hi Dmitry,
> 
> Yes, our firmware supports HID over I2C.  However, some of our
> customers often do not want to use HID to handle our hardware; even
> they don't install the generic HID driver neither.  In such case, we
> need to distinguish what generation of our device customer's has. And
> to do so, we check I2C HID descriptor even though the driver is not
> working with HID driver components, but this one.  That is why I2C HID
> descriptor is used there. It is called, but the situation with this
> driver is not supposed to work as a HID device.

I would like to understand better why the customers do not want to use
HID. There needs to be a _very_ strong reason to essentially duplicate
HID layer in a vendor driver and I inclined to say that such customers
would need to patch their kernels themselves.

Thanks.

-- 
Dmitry