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 19981C77B6E for ; Wed, 12 Apr 2023 07:49:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229832AbjDLHtb (ORCPT ); Wed, 12 Apr 2023 03:49:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38450 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229911AbjDLHt2 (ORCPT ); Wed, 12 Apr 2023 03:49:28 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8CA645FDC for ; Wed, 12 Apr 2023 00:49:22 -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 0F7016294B for ; Wed, 12 Apr 2023 07:49:22 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2514AC433EF; Wed, 12 Apr 2023 07:49:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1681285761; bh=3rHTGUDRtKSq4QhR1c4U5OVbHRA8KKZDYGPU/MvfgvY=; h=Subject:To:From:Date:From; b=OX+b63ze1gIE82WBlHy6wRRl1le57viujSsBZgRquW48AbBLFIBWmbmh57d6/lWnT 3WbKhIwjsLCIIBgg9emQnKPYnGKORty2G8XJUQXJHc14RFapAW8cbP8m/TN787mtYW UPjNxcsr09n+krai9AV678JSNSQ/GQQVq3v0s2Sg= Subject: patch "iio: addac: stx104: Fix race condition when converting" added to char-misc-testing To: william.gray@linaro.org, Jonathan.Cameron@huawei.com, Stable@vger.kernel.org From: Date: Wed, 12 Apr 2023 09:47:39 +0200 Message-ID: <2023041239-deplored-canning-326f@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-testing 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 be merged to the char-misc-next branch sometime soon, after it passes testing, and the merge window is open. 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