From patchwork Thu Mar 30 10:21:00 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Cercueil X-Patchwork-Id: 13193786 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 AB04DC6FD1D for ; Thu, 30 Mar 2023 10:21:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231316AbjC3KVU (ORCPT ); Thu, 30 Mar 2023 06:21:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39482 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231314AbjC3KVR (ORCPT ); Thu, 30 Mar 2023 06:21:17 -0400 Received: from aposti.net (aposti.net [89.234.176.197]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8046C8A47; Thu, 30 Mar 2023 03:21:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=crapouillou.net; s=mail; t=1680171667; 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; bh=wiu86Bom9SiZH9wS7LEFisDVIvTWugztSoKHUIOyNN4=; b=s1e1N0U5Qd95DMQsIoN0TqQUu/34vQG6++4q+0/2CfJ2U+asCFThFCFpmr6BkklDJ9cZ54 T9LkxLwIuFLyYddgPrwAyOTXSiwdC+r/6rC+6y/acw9uDVi5nhzRNDInNpYEYSwG2foP9n QNc2+NYXIKFlNZoYObEWlAE8zwcw4uo= From: Paul Cercueil To: Jonathan Cameron , Lars-Peter Clausen , Michael Hennerich Cc: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, Paul Cercueil , Alisa Roman Subject: [PATCH] iio: adc: ad7192: Change "shorted" channels to differential Date: Thu, 30 Mar 2023 12:21:00 +0200 Message-Id: <20230330102100.17590-1-paul@crapouillou.net> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org The AD7192 provides a specific channel configuration where both negative and positive inputs are connected to AIN2. This was represented in the ad7192 driver as a IIO channel with .channel = 2 and .extended_name set to "shorted". The problem with this approach, is that the driver provided two IIO channels with the identifier .channel = 2; one "shorted" and the other not. This goes against the IIO ABI, as a channel identifier should be unique. Address this issue by changing "shorted" channels to being differential instead, with channel 2 vs. itself, as we're actually measuring AIN2 vs. itself. Note that the fix tag is for the commit that moved the driver out of staging. The bug existed before that, but backporting would become very complex further down and unlikely to happen. Fixes: b581f748cce0 ("staging: iio: adc: ad7192: move out of staging") Signed-off-by: Paul Cercueil Co-developed-by: Alisa Roman Signed-off-by: Alisa Roman Reviewed-by: Nuno Sa --- drivers/iio/adc/ad7192.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c index 55a6ab591016..99bb604b78c8 100644 --- a/drivers/iio/adc/ad7192.c +++ b/drivers/iio/adc/ad7192.c @@ -897,10 +897,6 @@ static const struct iio_info ad7195_info = { __AD719x_CHANNEL(_si, _channel1, -1, _address, NULL, IIO_VOLTAGE, \ BIT(IIO_CHAN_INFO_SCALE), ad7192_calibsys_ext_info) -#define AD719x_SHORTED_CHANNEL(_si, _channel1, _address) \ - __AD719x_CHANNEL(_si, _channel1, -1, _address, "shorted", IIO_VOLTAGE, \ - BIT(IIO_CHAN_INFO_SCALE), ad7192_calibsys_ext_info) - #define AD719x_TEMP_CHANNEL(_si, _address) \ __AD719x_CHANNEL(_si, 0, -1, _address, NULL, IIO_TEMP, 0, NULL) @@ -908,7 +904,7 @@ static const struct iio_chan_spec ad7192_channels[] = { AD719x_DIFF_CHANNEL(0, 1, 2, AD7192_CH_AIN1P_AIN2M), AD719x_DIFF_CHANNEL(1, 3, 4, AD7192_CH_AIN3P_AIN4M), AD719x_TEMP_CHANNEL(2, AD7192_CH_TEMP), - AD719x_SHORTED_CHANNEL(3, 2, AD7192_CH_AIN2P_AIN2M), + AD719x_DIFF_CHANNEL(3, 2, 2, AD7192_CH_AIN2P_AIN2M), AD719x_CHANNEL(4, 1, AD7192_CH_AIN1), AD719x_CHANNEL(5, 2, AD7192_CH_AIN2), AD719x_CHANNEL(6, 3, AD7192_CH_AIN3), @@ -922,7 +918,7 @@ static const struct iio_chan_spec ad7193_channels[] = { AD719x_DIFF_CHANNEL(2, 5, 6, AD7193_CH_AIN5P_AIN6M), AD719x_DIFF_CHANNEL(3, 7, 8, AD7193_CH_AIN7P_AIN8M), AD719x_TEMP_CHANNEL(4, AD7193_CH_TEMP), - AD719x_SHORTED_CHANNEL(5, 2, AD7193_CH_AIN2P_AIN2M), + AD719x_DIFF_CHANNEL(5, 2, 2, AD7193_CH_AIN2P_AIN2M), AD719x_CHANNEL(6, 1, AD7193_CH_AIN1), AD719x_CHANNEL(7, 2, AD7193_CH_AIN2), AD719x_CHANNEL(8, 3, AD7193_CH_AIN3),