linux-kernel - Re: [PATCH v2 2/2] regmap: stop splitting writes to non incrementing registers

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Message-ID: <20200120180945.GL6852@sirena.org.uk>
Date:   Mon, 20 Jan 2020 18:09:45 +0000
From:   Mark Brown <broonie@...nel.org>
To:     Ben Whitten <ben.whitten@...il.com>
Cc:     linux-kernel@...r.kernel.org, afaerber@...e.de,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>
Subject: Re: [PATCH v2 2/2] regmap: stop splitting writes to non incrementing
 registers

On Sat, Jan 18, 2020 at 08:56:25PM +0000, Ben Whitten wrote:
> When writing to non incrementing registers we should not split
> the writes in any way, writing in one transaction.

That's not an obviously true statement.  If the user is intentionally
writing to a non-incrementing register and intends to stuff a block of
data into that one register via regmap_noinc_write() then sure but if
we've come in through a path that isn't specifically for the device or
is using one of the generic APIs then it's going to expect that the
framework will hide the unfortunate choices of the chip implementors and
split the I/O up.

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