From mboxrd@z Thu Jan 1 00:00:00 1970 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 19594C77B6C for ; Thu, 13 Apr 2023 09:27:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229937AbjDMJ1q (ORCPT ); Thu, 13 Apr 2023 05:27:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53386 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229871AbjDMJ1p (ORCPT ); Thu, 13 Apr 2023 05:27:45 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49357106 for ; Thu, 13 Apr 2023 02:27:44 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D979863C11 for ; Thu, 13 Apr 2023 09:27:43 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EB6E1C433EF; Thu, 13 Apr 2023 09:27:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1681378063; bh=FkAhLDBaojd/IOevz2cUjkb0OahSiC1bnhYZeoBvjAk=; h=Subject:To:From:Date:From; b=OkGZK7hgkULOz6fzzyv/R4VFrXOI0ubdvL36VVwX3Bwdk/o0i3sN8vqOr2VOyufY+ mD9muiScmwLuz7mtqwdEJCiD+06TlGKc97FIuNDd8fny4wilPosp81WJIJ990a3F5v tQ5e4k3OdDzTsLa98Y05gYUDooH1sXqWFwGH0eYY= Subject: patch "iio: addac: stx104: Fix race condition when converting" added to char-misc-next To: william.gray@linaro.org, Jonathan.Cameron@huawei.com, Stable@vger.kernel.org From: Date: Thu, 13 Apr 2023 11:25:19 +0200 Message-ID: <2023041319-letter-smoky-320f@gregkh> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled iio: addac: stx104: Fix race condition when converting to my char-misc git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git in the char-misc-next branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will also be merged in the next major kernel release during the merge window. If you have any questions about this process, please let me know. >From 4f9b80aefb9e2f542a49d9ec087cf5919730e1dd Mon Sep 17 00:00:00 2001 From: William Breathitt Gray Date: Thu, 6 Apr 2023 10:40:11 -0400 Subject: iio: addac: stx104: Fix race condition when converting analog-to-digital The ADC conversion procedure requires several device I/O operations performed in a particular sequence. If stx104_read_raw() is called concurrently, the ADC conversion procedure could be clobbered. Prevent such a race condition by utilizing a mutex. Fixes: 4075a283ae83 ("iio: stx104: Add IIO support for the ADC channels") Signed-off-by: William Breathitt Gray Link: https://lore.kernel.org/r/2ae5e40eed5006ca735e4c12181a9ff5ced65547.1680790580.git.william.gray@linaro.org Cc: Signed-off-by: Jonathan Cameron --- drivers/iio/addac/stx104.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/iio/addac/stx104.c b/drivers/iio/addac/stx104.c index 4239aafe42fc..8730b79e921c 100644 --- a/drivers/iio/addac/stx104.c +++ b/drivers/iio/addac/stx104.c @@ -117,6 +117,8 @@ static int stx104_read_raw(struct iio_dev *indio_dev, return IIO_VAL_INT; } + mutex_lock(&priv->lock); + /* select ADC channel */ iowrite8(chan->channel | (chan->channel << 4), ®->achan); @@ -127,6 +129,8 @@ static int stx104_read_raw(struct iio_dev *indio_dev, while (ioread8(®->cir_asr) & BIT(7)); *val = ioread16(®->ssr_ad); + + mutex_unlock(&priv->lock); return IIO_VAL_INT; case IIO_CHAN_INFO_OFFSET: /* get ADC bipolar/unipolar configuration */ -- 2.40.0