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Date:   Fri, 2 Dec 2022 23:42:06 -0800
From:   Eirin Nya <nyanpasu256@gmail.com>
To:     "phoenix" <phoenix@emc.com.tw>
Cc:     "'Dmitry Torokhov'" <dmitry.torokhov@gmail.com>,
        <linux-input@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        "'Josh.Chen'" <josh.chen@emc.com.tw>
Subject: Re: [PATCH V2 3/3] Input: elantech - Fix incorrectly halved
 touchpad range on ELAN v3 touchpads
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> If the setting is indeed double resolution, can we simply multiply 
> x_max and y_max by 2 instead of re-querying it?

Perhaps in some laptops, x_max or y_max is odd when resolution is
doubled, and rounded up or down in half-resolution mode, so multiplying
the half-resolution size by 2 results in a slightly incorrect full
size. I don't know if that's the case in other touchpads, but my
laptop's touchpad has even size in full-resolution (doubled) mode,
meaning it doesn't round its size in half-resolution mode (so
multiplying both values by 2 would work on my machine).

On Wed, 30 Nov 2022 19:22:25 +0800
"phoenix" <phoenix@emc.com.tw> wrote:

> Consulted with FW team, we suggest re-querying x/y resolution after
> setting absolute mode.

My current patch re-queries x/y resolution after setting absolute mode.
If this is the process that Elan's FW team recommends, should the patch
be kept as-is?