From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 40BC72F25F4; Mon, 27 Apr 2026 11:30:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777289411; cv=none; b=EtOB25/OKvHZWnULrqoa00d5b58/M37CUYXsxzRG0Wroa0aIHZ060/BAWj2HTMKbtxsqufSEUNekgQGC55MmR8NQlKS0C8bUU91/vgfnQ6aaIVkr/zsqXppI+Ev3zCMWg9nicpw9PnJ/0mRo4hf387v4Xqlsq5XHEnQopMNH+0o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777289411; c=relaxed/simple; bh=ln2xDqNwzgp1IlNe5nNZRvuJhnMixrpbcxGzvS2tsWQ=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=fCvgNvUr0zIKrWTp+Nr2Fekrc5tyLoP0UGUXDug30eNaSfveLbzqnkrWevabnk21Ya+CdQmqzJFzcsmxDyCw2HXi5s+ziPe21lOfZ8ptwEOmW2kczAyS5wpTWAhYKejHzRAiquZcSCtUWmRRCs4nIXCRbHilVNjkRgnYlfIrvxs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=MxfaYK1l; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="MxfaYK1l" Received: by smtp.kernel.org (Postfix) with ESMTPS id 21AABC2BCC4; Mon, 27 Apr 2026 11:30:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1777289411; bh=ln2xDqNwzgp1IlNe5nNZRvuJhnMixrpbcxGzvS2tsWQ=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=MxfaYK1lTzn9i2SqANMj2GgtYmmocnEmvr2lGQhobFOQSEvTizvkZ06ThMuza4wc2 xhbIl2Y10sVxgCabTsEZEWFpWFeOo+RA4gvIEszZHYrmjwxwIoArr7tQUmt7SLfO+l P/ei9FojJZ3KSdjYLzcUm2t0C7RCo14XUmo01A5wrQMvD5devbtEqUQjHJ2Zxo+yXZ pQXutLxoZmDvXeHF0+tq1bDyJCM1TXfQuN/EBxpJVku1axKzrFnOvrR2O6wBCSPwbF 2BFtJeFdz9NTV+3hm2eaelPJrkWe0WyYIMf1dUuqAQagLIVGvdcHdxNApzIcyrdlIL fhrF7Ca/WIVTg== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 18610FF885E; Mon, 27 Apr 2026 11:30:11 +0000 (UTC) From: Rodrigo Alencar via B4 Relay Date: Mon, 27 Apr 2026 12:30:10 +0100 Subject: [PATCH v2 03/11] iio: dac: ad5686: acquire lock when doing powerdown control Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260427-ad5686-fixes-v2-3-188e05199368@analog.com> References: <20260427-ad5686-fixes-v2-0-188e05199368@analog.com> In-Reply-To: <20260427-ad5686-fixes-v2-0-188e05199368@analog.com> To: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, Stefan Popa , Jonathan Cameron , Greg Kroah-Hartman , Michael Auchter , Jonathan Cameron Cc: Lars-Peter Clausen , Michael Hennerich , Jonathan Cameron , David Lechner , Andy Shevchenko , Rodrigo Alencar X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1777289409; l=1335; i=rodrigo.alencar@analog.com; s=default; h=from:subject:message-id; bh=3ewgFdIgEvpo865lUj9Vjv8qanWqzVP1oPspiMSNexs=; b=aUnu6PXrDBJdtmqke/3iJAh6vJ7wQb1/WmPh5SwEGqVDFHa+tieebNadQlWURqhRY8axvbBnP mlL8KFOxLwlCLMBXIr7dOlYtt+hRBCLst3I4ekyy4cHTJ7GDRtris3f X-Developer-Key: i=rodrigo.alencar@analog.com; a=ed25519; pk=ULeHbgU/OYh/PG/4anHDfLgldFItQHAhOktYRVLMFRo= X-Endpoint-Received: by B4 Relay for rodrigo.alencar@analog.com/default with auth_id=561 X-Original-From: Rodrigo Alencar Reply-To: rodrigo.alencar@analog.com From: Rodrigo Alencar Protect write access of pwr_down_mode and pwr_down_mask fields with existing mutex lock. Each channel exposes their own attributes for controlling powerdown modes and powerdown state. This fixes potential race conditions as those functions perform non-atomic read-modify-write operations to those pwr_down_* fields. This issue exists since the ad5686 driver was first introduced. Fixes: c2f37c8dcadc ("iio: dac: New driver for AD5686R, AD5685R, AD5684R Digital to analog converters") Signed-off-by: Rodrigo Alencar --- drivers/iio/dac/ad5686.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/iio/dac/ad5686.c b/drivers/iio/dac/ad5686.c index 24f928ea2b91..aa17ed6aee43 100644 --- a/drivers/iio/dac/ad5686.c +++ b/drivers/iio/dac/ad5686.c @@ -39,6 +39,8 @@ static int ad5686_set_powerdown_mode(struct iio_dev *indio_dev, { struct ad5686_state *st = iio_priv(indio_dev); + guard(mutex)(&st->lock); + st->pwr_down_mode &= ~(0x3 << (chan->channel * 2)); st->pwr_down_mode |= ((mode + 1) << (chan->channel * 2)); @@ -77,6 +79,8 @@ static ssize_t ad5686_write_dac_powerdown(struct iio_dev *indio_dev, if (ret) return ret; + guard(mutex)(&st->lock); + if (readin) st->pwr_down_mask |= (0x3 << (chan->channel * 2)); else -- 2.43.0