From: Marek Vasut <marex@denx.de>
To: Hector Palacios <hector.palacios@digi.com>
Subject: Re: [PATCH v2 1/5] iio: mxs-lradc: change the realbits to 12
Date: Fri, 19 Jul 2013 15:56:46 +0200
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Cc: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org,
        devicetree-discuss@lists.ozlabs.org,
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        lars@metafoo.de, fabio.estevam@freescale.com
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Dear Hector Palacios,

> The LRADC virtual channels have an 18 bit field to store the sum of up
> to 2^5 accumulated samples. The read_raw function however only operates
> over a single sample (12 bit resolution).
> In order to use this field for scaling operations, we need it to be the
> exact resolution value of the LRADC.
> Besides, the driver was using an 18 bit mask (LRADC_CH_VALUE_MASK) to
> report touch coordinates to userland. A 12 bit mask should be used instead
> or else the touch libraries will expect a coordinates range between 0
> and 0x3ffff (18 bits), instead of between 0 and 0xfff (12 bits).
> 
> Signed-off-by: Hector Palacios <hector.palacios@digi.com>

Acked-by: Marek Vasut <marex@denx.de>

Best regards,
Marek Vasut
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