From mboxrd@z Thu Jan  1 00:00:00 1970
From: Martin Fuzzey <mfuzzey@parkeon.com>
Subject: Re: [11/51] Input: atmel_mxt_ts - Implement CRC check for configuration
 data
Date: Wed, 18 Sep 2013 18:59:10 +0200
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References: <1372337366-9286-12-git-send-email-nick.dyer@itdev.co.uk>
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To: Nick Dyer <nick.dyer@itdev.co.uk>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>, Daniel Kurtz <djkurtz@chromium.org>, Henrik Rydberg <rydberg@euromail.se>, Joonyoung Shim <jy0922.shim@samsung.com>, Alan Bowens <Alan.Bowens@atmel.com>, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, Peter Meerwald <pmeerw@pmeerw.net>, Benson Leung <bleung@chromium.org>, Olof Johansson <olofj@chromium.org>

On 27/06/13 14:48, Nick Dyer wrote:
> The configuration is stored in NVRAM on the maXTouch chip. When the device is
> reset it reports a CRC of the stored configuration values. Therefore it isn't
> necessary to send the configuration on each probe - we can check the CRC
> matches and avoid a timeconsuming backup/reset cycle.
>
> Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>
> Acked-by: Benson Leung <bleung@chromium.org>
> -static unsigned mxt_extract_T6_csum(const u8 *csum)
> +static u16 mxt_extract_T6_csum(const u8 *csum)
>   {
>   	return csum[0] | (csum[1] << 8) | (csum[2] << 16);
>   }

Shouldn't this be u32?
It's losing data causing the checksums not to match for me.