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([2600:8803:e7e4:500:677a:56dd:37eb:cf53]) by smtp.gmail.com with ESMTPSA id 46e09a7af769-7ee2a1087b3sm8708313a34.25.2026.07.25.09.52.33 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 25 Jul 2026 09:52:34 -0700 (PDT) Message-ID: Date: Sat, 25 Jul 2026 11:52:32 -0500 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/2] iio: dac: mcp47a1: add support for new device To: Joshua Crofts , Andy Shevchenko Cc: Jonathan Cameron , =?UTF-8?Q?Nuno_S=C3=A1?= , Andy Shevchenko , Rob Herring , Krzysztof Kozlowski , Conor Dooley , linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260721-mcp47a1-add-support-v1-0-da045a2567e3@gmail.com> <20260721-mcp47a1-add-support-v1-2-da045a2567e3@gmail.com> <20260722083016.000062c4@gmail.com> Content-Language: en-US From: David Lechner In-Reply-To: <20260722083016.000062c4@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/22/26 1:30 AM, Joshua Crofts wrote: > On Tue, 21 Jul 2026 23:47:58 +0300 > Andy Shevchenko wrote: > >> On Tue, Jul 21, 2026 at 08:24:39PM +0200, Joshua Crofts wrote: >>> The Microchip MCP47A1 is a 6-bit volatile Digital-to-Analog converted >>> which communicates via I2C. >> >> >> ... >> >>> +static const struct regmap_config mcp47a1_regmap_config = { >>> + .name = "mcp47a1", >>> + .reg_bits = 8, >>> + .val_bits = 8, >>> + .max_register = MCP47A1_CMD_CODE, >>> +}; >> >> No cache? > > Hmmm, could you elaborate a bit more? I assume you're talking about > regcache but I'm not sure on how to use it here. > normally one would select the maple regcache type and add a callback for indicating which registers are volatile and and another config to indicate the initial register values after reset. however, it looks like there is only 1 register here, so probably not much point in that.