linux-kernel - Re: [RFC PATCH] regmap: force update_bits() to write to HW when reg is volatile

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Message-ID: <14d81f72-ab34-4405-b826-b52636d2be18@sirena.org.uk>
Date:   Fri, 28 Apr 2023 12:35:41 +0100
From:   Mark Brown <broonie@...nel.org>
To:     Matti Vaittinen <mazziesaccount@...il.com>
Cc:     Matti Vaittinen <matti.vaittinen@...rohmeurope.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>,
        Geert Uytterhoeven <geert@...ux-m68k.org>,
        linux-kernel@...r.kernel.org
Subject: Re: [RFC PATCH] regmap: force update_bits() to write to HW when reg
 is volatile

On Fri, Apr 28, 2023 at 08:44:06AM +0300, Matti Vaittinen wrote:
> In many cases the volatile registers are expected to be written to
> regardless of the existing value (because, the value of a volatile
> register can't be trusted to stay the same during RMW cycle). In fact, it
> is questionable if the volatile registers and regmap_update_bits()
> conceptually make sense without device specific map->reg_update_bits.

I think you're looking for regmap_write_bits() here.

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