Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [PATCH RESEND v2] virtio-input: add multi-touch support
To:     "Michael S. Tsirkin" <mst@redhat.com>
CC:     <virtualization@lists.linux-foundation.org>,
        <linux-kernel@vger.kernel.org>, <linux-input@vger.kernel.org>,
        <stable@vger.kernel.org>, Jason Wang <jasowang@redhat.com>,
        Gerd Hoffmann <kraxel@redhat.com>,
        Henrik Rydberg <rydberg@bitmath.org>,
        Mathias Crombez <mathias.crombez@faurecia.com>
References: <20201208210150.20001-1-vasyl.vavrychuk@opensynergy.com>
 <20201209030635-mutt-send-email-mst@kernel.org>
From:   Vasyl Vavrychuk <vasyl.vavrychuk@opensynergy.com>
Message-ID: <84310558-729b-d6d0-cf1a-e48febc3f001@opensynergy.com>
Date:   Sat, 19 Dec 2020 01:25:15 +0200
MIME-Version: 1.0
In-Reply-To: <20201209030635-mutt-send-email-mst@kernel.org>
Content-Type: text/plain; charset="utf-8"; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk


On 09.12.20 10:28, Michael S. Tsirkin wrote:
> On Tue, Dec 08, 2020 at 11:01:50PM +0200, Vasyl Vavrychuk wrote:
>> From: Mathias Crombez <mathias.crombez@faurecia.com>
>> Cc: stable@vger.kernel.org
> 
> I don't believe this is appropriate for stable, looks like
> a new feature to me.

Agree, removed.

>>
>> +config VIRTIO_INPUT_MULTITOUCH_SLOTS
>> +     depends on VIRTIO_INPUT
>> +     int "Number of multitouch slots"
>> +     range 0 64
>> +     default 10
>> +     help
>> +      Define the number of multitouch slots used. Default to 10.
>> +      This parameter is unused if there is no multitouch capability.
>> +
>> +      0 will disable the feature.
>> +
> 
> Most people won't be using this config so the defaults matter. So why 10? 10 fingers?
> 
> And where does 64 come from?

I have sent v3 version where number of slots it obtained from the host.

>> +     if (is_mt)
>> +             input_mt_init_slots(vi->idev,
>> +                                 CONFIG_VIRTIO_INPUT_MULTITOUCH_SLOTS,
>> +                                 INPUT_MT_DIRECT);
> 
> 
> Do we need the number in config space maybe? And maybe with a feature
> bit so host can find out whether guest supports MT?

I think it is not applicable in v3 which I sent, because number of slots 
is commit from the host. So, now host controls whether guest support MT.