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Date:   Sat, 6 Mar 2021 17:34:49 +0000
From:   Jonathan Cameron <jic23@kernel.org>
To:     "Hennerich, Michael" <Michael.Hennerich@analog.com>
Cc:     "zzzzArdelean, zzzzAlexandru" <alexandru.Ardelean@analog.com>,
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        "Sa, Nuno" <Nuno.Sa@analog.com>,
        "Bogdan, Dragos" <Dragos.Bogdan@analog.com>
Subject: Re: [PATCH v3 0/6] iio: Add output buffer support
Message-ID: <20210306173449.06f2f32b@archlinux>
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On Fri, 5 Mar 2021 08:57:08 +0000
"Hennerich, Michael" <Michael.Hennerich@analog.com> wrote:

> Hi Jonathan and others,
> 
> With output/dac buffer support the semantics of the scan_element type may change.
> 
> Today the Format is [be|le]:[s|u]bits/storagebitsXrepeat[>>shift].
> 
> While shift (if specified) is the shift that needs to be applied prior to masking out unused bits.
> 
> So far so good and it sounds universal. 
> 
> However, we use the right shift (operator) for that, which makes sense for capture devices.
> For output devices the more logical operator would be the left shift.
> 
> I'm not proposing a new Format here. I just want to get some agreement that for an output device
> 
> le:s12/16>>4  
> 
> is understood as a left shift of 4, since the unused bits are then on the LSB.

Good question. Guess I wasn't thinking ahead when I came up with that :)

I'm not sure I'd mind if we did decide to define a new format for output
buffers. Feels like it should be easy to do.

What do others think?

Jonathan


> 
> Thoughts?
> 
> Best Regards,
> Michael
> 
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