Date:   Mon, 27 Feb 2023 13:23:00 +0100
From:   Jean Delvare <jdelvare@suse.de>
To:     Sasha Levin <sashal@kernel.org>
Cc:     linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        Allen Ballway <ballway@chromium.org>,
        Jiri Kosina <jkosina@suse.cz>, jikos@kernel.org,
        benjamin.tissoires@redhat.com, groeck@chromium.org,
        alistair@alistair23.me, dmitry.torokhov@gmail.com,
        jk@codeconstruct.com.au, Jonathan.Cameron@huawei.com,
        cmo@melexis.com, u.kleine-koenig@pengutronix.de,
        linux-input@vger.kernel.org
Subject: Re: [PATCH AUTOSEL 5.15 10/25] HID: multitouch: Add quirks for
 flipped axes
Message-ID: <20230227132300.4a3c3fad@endymion.delvare>
In-Reply-To: <20230227020855.1051605-10-sashal@kernel.org>
References: <20230227020855.1051605-1-sashal@kernel.org>
        <20230227020855.1051605-10-sashal@kernel.org>
Organization: SUSE Linux
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Precedence: bulk

Hi Sasha,

On Sun, 26 Feb 2023 21:08:33 -0500, Sasha Levin wrote:
> From: Allen Ballway <ballway@chromium.org>
> 
> [ Upstream commit a2f416bf062a38bb76cccd526d2d286b8e4db4d9 ]
> 
> Certain touchscreen devices, such as the ELAN9034, are oriented
> incorrectly and report touches on opposite points on the X and Y axes.
> For example, a 100x200 screen touched at (10,20) would report (90, 180)
> and vice versa.
> 
> This is fixed by adding device quirks to transform the touch points
> into the correct spaces, from X -> MAX(X) - X, and Y -> MAX(Y) - Y.
> 
> Signed-off-by: Allen Ballway <ballway@chromium.org>
> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
> Signed-off-by: Sasha Levin <sashal@kernel.org>
> ---
>  drivers/hid/hid-multitouch.c             | 39 ++++++++++++++++++---
>  drivers/hid/hid-quirks.c                 |  6 ++++
>  drivers/hid/i2c-hid/i2c-hid-dmi-quirks.c | 43 ++++++++++++++++++++++++
>  drivers/hid/i2c-hid/i2c-hid.h            |  3 ++
>  4 files changed, 87 insertions(+), 4 deletions(-)
> (...)

Second rule of acceptance for stable patches:

 - It cannot be bigger than 100 lines, with context.

Clearly not met here.

To me, this commit is something distributions may want to backport if
their users run are likely to run the affected hardware. But it's out
of scope for stable kernel branches.

Thanks,
-- 
Jean Delvare
SUSE L3 Support