From patchwork Tue May 23 15:12:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herve Codina X-Patchwork-Id: 13252495 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 46851C77B75 for ; Tue, 23 May 2023 15:12:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237466AbjEWPMw (ORCPT ); Tue, 23 May 2023 11:12:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53164 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237467AbjEWPMu (ORCPT ); Tue, 23 May 2023 11:12:50 -0400 Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 115EB13E; Tue, 23 May 2023 08:12:45 -0700 (PDT) Received: (Authenticated sender: herve.codina@bootlin.com) by mail.gandi.net (Postfix) with ESMTPA id BB54AC0013; Tue, 23 May 2023 15:12:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1684854764; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=B5Rp2Pe2hP+HZpzHQ6QCIJu8OkM1HG2ZQQx1TOta918=; b=DCytTTlwfYZ07XCnOC1y/PBxT/gt5Bv3UFAB1EGhRvleTo7U3AOLO8sxWlvI8yCC0E5kJS hpdV6Nx4P+qyD22hEu+LTLixj4X2zB/efzVU0C2VRSSinU3m/rfAcPup0BHVQSk3uxYh2P mFRLWDfTLBEW1GBVHtMaEeP7q5QAmR7hEaY2V4cwIUPHj2Ynid7erDgBv2fbMX7Hl3C6RA Ptx7ur7w85pztC+90lDvuhCgjxyjfuv32j7XqgLXnRmgq+2aYluashCX0sIDzD+SyjQeuo GXwV0M4nRAM/LZamGyqdUMVZ4aKLA/gi73pV79ZxUbqjigH9hGmJKAy5M8Yvfw== From: Herve Codina To: Herve Codina , Liam Girdwood , Mark Brown , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Jonathan Cameron , Lars-Peter Clausen , Jaroslav Kysela , Takashi Iwai , Kuninori Morimoto Cc: alsa-devel@alsa-project.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, Christophe Leroy , Thomas Petazzoni Subject: [PATCH v2 4/9] iio: consumer.h: Fix raw values documentation notes Date: Tue, 23 May 2023 17:12:18 +0200 Message-Id: <20230523151223.109551-5-herve.codina@bootlin.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230523151223.109551-1-herve.codina@bootlin.com> References: <20230523151223.109551-1-herve.codina@bootlin.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org The raw values notes mention 'ADC counts' and are not fully accurate. Reword the notes in order to remove the 'ADC counts' and describe the conversion needed between a raw value and a value in the standard units. Signed-off-by: Herve Codina Acked-by: Jonathan Cameron --- include/linux/iio/consumer.h | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h index 6802596b017c..f536820b9cf2 100644 --- a/include/linux/iio/consumer.h +++ b/include/linux/iio/consumer.h @@ -201,8 +201,9 @@ struct iio_dev * @chan: The channel being queried. * @val: Value read back. * - * Note raw reads from iio channels are in adc counts and hence - * scale will need to be applied if standard units required. + * Note, if standard units are required, raw reads from iio channels + * need the offset (default 0) and scale (default 1) to be applied + * as (raw + offset) * scale. */ int iio_read_channel_raw(struct iio_channel *chan, int *val); @@ -212,8 +213,9 @@ int iio_read_channel_raw(struct iio_channel *chan, * @chan: The channel being queried. * @val: Value read back. * - * Note raw reads from iio channels are in adc counts and hence - * scale will need to be applied if standard units required. + * Note, if standard units are required, raw reads from iio channels + * need the offset (default 0) and scale (default 1) to be applied + * as (raw + offset) * scale. * * In opposit to the normal iio_read_channel_raw this function * returns the average of multiple reads. @@ -281,8 +283,9 @@ int iio_read_channel_attribute(struct iio_channel *chan, int *val, * @chan: The channel being queried. * @val: Value being written. * - * Note raw writes to iio channels are in dac counts and hence - * scale will need to be applied if standard units required. + * Note that for raw writes to iio channels, if the value provided is + * in standard units, the affect of the scale and offset must be removed + * as (value / scale) - offset. */ int iio_write_channel_raw(struct iio_channel *chan, int val); @@ -292,8 +295,9 @@ int iio_write_channel_raw(struct iio_channel *chan, int val); * @chan: The channel being queried. * @val: Value read back. * - * Note raw reads from iio channels are in adc counts and hence - * scale will need to be applied if standard units are required. + * Note, if standard units are required, raw reads from iio channels + * need the offset (default 0) and scale (default 1) to be applied + * as (raw + offset) * scale. */ int iio_read_max_channel_raw(struct iio_channel *chan, int *val); @@ -308,8 +312,9 @@ int iio_read_max_channel_raw(struct iio_channel *chan, int *val); * For ranges, three vals are always returned; min, step and max. * For lists, all the possible values are enumerated. * - * Note raw available values from iio channels are in adc counts and - * hence scale will need to be applied if standard units are required. + * Note, if standard units are required, raw available values from iio + * channels need the offset (default 0) and scale (default 1) to be applied + * as (raw + offset) * scale. */ int iio_read_avail_channel_raw(struct iio_channel *chan, const int **vals, int *length);