From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f178.google.com (mail-oi1-f178.google.com [209.85.167.178]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 76CA1217723 for ; Sat, 4 Apr 2026 16:04:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.178 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775318686; cv=none; b=CtlSIdGFGObXMEgiZgx+f729H5NRaTMCzaCbdD9V81zfFFkWbJj/eRyvqmnxhntRTRxRznmzMOPFO8EEuhTI93p6nDwVrH3i+Ne63M5aAbMHXj8Tg6uZerwA3gJcZz/HAi7cZLsxv1iC2wyU4LLvP4cdzSO0I/YZZK+22aA/WV0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775318686; c=relaxed/simple; bh=vR1gq2NMqok21ndSyGwYozpFx0zjnkqwevwKB53zh/c=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=TlujhBeE/d3Hp0YOUEH3tkxHKksqDT1Scx4VSjapqLYG2H1wLKv12FNfhVPEafdv1OaCOIgYl0zxmX99N0iDrXDLTFRNZmz8s7ZAAUzn/IzQRH5x5XiKTAhoRiHWT+9Jyu5LVzcM0qdE3SCfwHgmQr0tQMkPTvDnBWfk7lRNYYQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=baylibre.com; spf=pass smtp.mailfrom=baylibre.com; dkim=pass (2048-bit key) header.d=baylibre-com.20251104.gappssmtp.com header.i=@baylibre-com.20251104.gappssmtp.com header.b=sZq/1Jva; arc=none smtp.client-ip=209.85.167.178 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=baylibre.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=baylibre.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=baylibre-com.20251104.gappssmtp.com header.i=@baylibre-com.20251104.gappssmtp.com header.b="sZq/1Jva" Received: by mail-oi1-f178.google.com with SMTP id 5614622812f47-466ec4c6852so1348619b6e.3 for ; Sat, 04 Apr 2026 09:04:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20251104.gappssmtp.com; s=20251104; t=1775318683; x=1775923483; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=+wzVnwcdwZGk4+8lGBJhDoWkSR8wcMoOHjT2H8NPOcE=; b=sZq/1JvayMpIvUAJ3GMOIofmPN5JsRVmo43dh4DsfM6gx5kfGJ/Yr4UiXWfir9GZ6O XCdJTMryYniz7l9i7hyXaVBfNSWZtgW6iZLv1ayAeniTa19ELQjITGdReKreq53FY4vy 02hAEsC6pcuQpuIR8uCGhURsrV7qx6rK8R2LmeUQtG9VhlhsDnqFGA2erIIStF5GXEna uuMq9+uAOuxEa1qJd97C+wFbDsYFmEHjtTJCZA/NwTQjRvWqsZBYdHOlZJtOif+t8P/u DgoeuipavxbiyQKlDnjISszhKtvOax2pw/1B/qhCI6CadewMN+XtybXuWskrMablf/or n6aQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775318683; x=1775923483; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=+wzVnwcdwZGk4+8lGBJhDoWkSR8wcMoOHjT2H8NPOcE=; b=XhM2G/3ca/uAHNNYWkfMtUTuPxxhxXBFl2EYdeWI1eFoDyNUv7jNWGRRQEAzH8RCv3 Q5jIbKYf5C6LxfzvTlEF+7DKPX25mtEqouq3X9xx4kx8VhsjhEJ5r7uy95lT907zffMw LqDu+ZjDrwd92fMt44Leyqd5FoQW1TDzXuUC5Mc4PKmsKhV0J1eMVNdrhPsbGSNZL3O/ wMsGtCBdaXF/M03jXahLkSJm4EPkhpW95wUiLyQLDfGXGiL2H6mPGJcvDhB/k4UfhWAP NETSCZwWcNk6MTBaHogEJHcsa/EOyEaO0xwhbaO0IkLbyzvHtpNGnR7qSA6PJLB0FDv6 Hm+g== X-Forwarded-Encrypted: i=1; AJvYcCXEaRQmDzhUwmSWR8dspWid8f8ZJYxzcv3vmz1HjUEr5Mvwmcaw882As9Ng8uguFW9XsQ1xIrdZJNaBQKw=@vger.kernel.org X-Gm-Message-State: AOJu0YzDCfVEqCMd54nlY9I7PIR5gjooOsWAzUzME5K0xs0mqH/Et9BO tCXcjKuuLYVawPXELhjZdb+65+YegrWA+9cYNso0bYO1/hKfi7hg4D6UFr2f8MtHdGE= X-Gm-Gg: AeBDieudD0et5X+Yz/zZPlCTB2A5yHPhlAB+Tl/P8ldB2EFanXjeKgVGakY8tvqN0IU GLaUQJbW00+f2075HBv/TSjgS5KPLYpvz8D712p9F8CAymj0FPDy6yPnMYNVas6aSVjQScLjMl9 vKsC9B3gUh3BolrWANXdOUwizbwigU545yPKXHxbCEE+BNs7+BmkShHZgeoQZk2V4psckaW8Ozi ZTIy9xkbqDYdMM+DSX40183ph913hDZsKbpDf3IlrkOz6La0XztB0HvZV8brPb3UBs4x2GlmkKG KnutAf5kGn/Z91HvryKdnnwj3iWw5aVlSlORb8KZ9PGqQLbUI6Qa7q6SzVW+xGOJVQilyqoYeRh 0KFvziF6I1giEO3a0aShgrtaJ2elhtdVVQ57pKOUX7YIlK3tyr3Hd6JR9x1bfSUfeOb1iViO8cv /8gLwL/qLo6jGAhEME8k/W4cf+L0bRo/yYL5/nTFJ6Gr12ha7QMPt438kOVhSCLfmrepQR1Fdo8 w== X-Received: by 2002:a05:6808:c2c4:b0:467:32c1:ad01 with SMTP id 5614622812f47-46ef8a4c2d4mr3215290b6e.50.1775318683418; Sat, 04 Apr 2026 09:04:43 -0700 (PDT) Received: from ?IPV6:2600:8803:e7e4:500:e14e:bcc6:3f95:26eb? ([2600:8803:e7e4:500:e14e:bcc6:3f95:26eb]) by smtp.gmail.com with ESMTPSA id 5614622812f47-46d92a53169sm5285749b6e.10.2026.04.04.09.04.41 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 04 Apr 2026 09:04:42 -0700 (PDT) Message-ID: <1fdd057a-3234-442c-b1fc-88bfcbe542b4@baylibre.com> Date: Sat, 4 Apr 2026 11:04:41 -0500 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 4/5] iio: adc: ad799x: cache regulator voltages during probe To: Archit Anant , jic23@kernel.org Cc: lars@metafoo.de, Michael.Hennerich@analog.com, nuno.sa@analog.com, andy@kernel.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260403080614.14213-1-architanant5@gmail.com> <20260403080614.14213-5-architanant5@gmail.com> Content-Language: en-US From: David Lechner In-Reply-To: <20260403080614.14213-5-architanant5@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 4/3/26 3:06 AM, Archit Anant wrote: > Since the reference voltage for this ADC is not expected to > change at runtime, determine the active reference voltage (either VREF > or VCC) during probe() and cache it in a single variable in the state > structure. > > This improves the performance of ad799x_read_raw() and removes the > dependency on the regulator pointers during fast-path reads. To make this claim, it should be backed up by performance measurements. I would drop it since I don't think it would actually make a measurable difference and it is not in a hot path anyway.