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Date: Sun, 23 Aug 2026 01:51:00 +0100
From: Jonathan Cameron <jic23@kernel.org>
To: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Ariana Lazar <ariana.lazar@microchip.com>, David Lechner
 <dlechner@baylibre.com>, Nuno =?UTF-8?B?U8Oh?= <nuno.sa@analog.com>, Andy
 Shevchenko <andy@kernel.org>, Rob Herring <robh@kernel.org>, Krzysztof
 Kozlowski <krzk+dt@kernel.org>, Conor Dooley <conor+dt@kernel.org>,
 linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org,
 devicetree@vger.kernel.org
Subject: Re: [PATCH v4 1/9] iio: dac: mcp47feb02: initialize dac_data field
 in channel data struct at probe
Message-ID: <20260823015100.74b6f615@jic23-huawei>
In-Reply-To: <aoW657jDvmMiOsaX@ashevche-desk.local>
References: <20260819-mcp47feb02_refactor-v4-0-beb2aa3bfd09@microchip.com>
	<20260819-mcp47feb02_refactor-v4-1-beb2aa3bfd09@microchip.com>
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On Wed, 19 Aug 2026 17:17:11 +0300
Andy Shevchenko <andriy.shevchenko@intel.com> wrote:

> On Wed, Aug 19, 2026 at 03:41:05PM +0300, Ariana Lazar wrote:
> > Read DAC value register to initialize corresponding field in channel_data
> > struct when the module is inserted.  
> 
> Since we have a cache enabled for regmap, can we rather read back initial HW
> values at the probe time for all non-volatile or precise registers?
> 

That should indeed be explored.  This is also missing any description of 'why'
this needs to be read and cached at all.

Jonathan