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[86.49.244.181]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-496b49a6e17sm57067605e9.13.2026.07.25.03.17.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 25 Jul 2026 03:17:30 -0700 (PDT) Date: Sat, 25 Jul 2026 12:17:28 +0200 From: Joshua Crofts To: Jonathan Cameron Cc: David Lechner , Nuno =?UTF-8?B?U8Oh?= , Andy Shevchenko , Rob Herring , Krzysztof Kozlowski , Conor Dooley , linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] iio: dac: mcp47a1: add support for new device Message-ID: <20260725121728.17ddbc7a@systembl0wer> In-Reply-To: <20260725001417.159653b8@jic23-huawei> References: <20260721-mcp47a1-add-support-v1-0-da045a2567e3@gmail.com> <20260721-mcp47a1-add-support-v1-2-da045a2567e3@gmail.com> <20260725001417.159653b8@jic23-huawei> X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-redhat-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Sat, 25 Jul 2026 00:14:17 +0100 Jonathan Cameron wrote: > Given the really small number of registers, regmap does seem like > it might be overkill My thought was that regmap is preferred over i2c_smbus_* functions, but that is a simple enough move. ... > > + /* > > + * This is a volatile DAC which doesn't have an ID register, instead > > + * the value register is set to 0x20 every Power-on-Reset (table 4-1). > > + * Any other read value at startup could indicate that the device is > > + * damaged etc. > > or some earlier software wrote it and the all the regulators are stubs > provided as they can't be turned off by software. > > I'd drop this test - it is a bit too flakey as a way to tell the chip > is there and working. Yeah, fair enough, there's a reason why it just reports it as dev_info(). -- Kind regards, Joshua Crofts