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 X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 65C1EC3F2CD for ; Sun, 1 Mar 2020 15:56:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2FAE821775 for ; Sun, 1 Mar 2020 15:56:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583078219; bh=qhEfjHVx8EO32+N08TyPXheahfXEzN3WpIdl8Osp8XA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=GhGX3hSiBC7CCK28/qDVBlsa801jA2Gej1Q7BuMAEHwIR45k62XYhmYcsqRvwe72a Iz1OPo5tCMqphQOdW3xEYp5K97KpwunDRZHx88fXnaEJPT2J07+VPDCKftpu9Sg3PV 6wAHQprF++sZNduHIHer5t0C+A/M43AveZiYVkdI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726536AbgCAP46 (ORCPT ); Sun, 1 Mar 2020 10:56:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:36488 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725945AbgCAP46 (ORCPT ); Sun, 1 Mar 2020 10:56:58 -0500 Received: from archlinux (cpc149474-cmbg20-2-0-cust94.5-4.cable.virginm.net [82.4.196.95]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 02E9921775; Sun, 1 Mar 2020 15:56:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583078217; bh=qhEfjHVx8EO32+N08TyPXheahfXEzN3WpIdl8Osp8XA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=MK3ALxR5sxnFmHUjjV2VwAZvzvnAKhhC+LA6DQpzovSWNd/5HrAvZ1YmRElCRiMfM oLWRpMO0IgaR/3XWc7trsG1pvqlKmGgJvcBkh1u/dPIMYHLSU36RseMSFhR2Gylb1L lJyWGYj+TUS5Oj6l9WOGz5YeKowrT2nEHZI1pepU= Date: Sun, 1 Mar 2020 15:56:51 +0000 From: Jonathan Cameron To: Alexandru Ardelean Cc: , Subject: Re: [PATCH v2 3/3] iio: imu: adis: add a note better explaining state_lock Message-ID: <20200301155651.1e341eb8@archlinux> In-Reply-To: <20200225103319.20751-3-alexandru.ardelean@analog.com> References: <20200225103319.20751-1-alexandru.ardelean@analog.com> <20200225103319.20751-3-alexandru.ardelean@analog.com> X-Mailer: Claws Mail 3.17.4 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Tue, 25 Feb 2020 12:33:19 +0200 Alexandru Ardelean wrote: > The 'state_lock' mutex was renamed from 'txrx_lock' in a previous patch and > is intended to be used by ADIS drivers to protect the state of devices > during consecutive R/W ops. > The initial patch that introduced this change did not do a good [well, any] > job at explaining this. This patch adds a comment to the 'state_lock' > better explaining it's use. > > Signed-off-by: Alexandru Ardelean Applied. Thanks, Jonathan > --- > include/linux/iio/imu/adis.h | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/include/linux/iio/imu/adis.h b/include/linux/iio/imu/adis.h > index 20339025c75f..dd8219138c2e 100644 > --- a/include/linux/iio/imu/adis.h > +++ b/include/linux/iio/imu/adis.h > @@ -98,6 +98,17 @@ struct adis { > const struct adis_data *data; > struct adis_burst *burst; > > + /** > + * The state_lock is meant to be used during operations that require > + * a sequence of SPI R/W in order to protect the SPI transfer > + * information (fields 'xfer', 'msg' & 'current_page') between > + * potential concurrent accesses. > + * This lock is used by all "adis_{functions}" that have to read/write > + * registers. These functions also have unlocked variants > + * (see "__adis_{functions}"), which don't hold this lock. > + * This allows users of the ADIS library to group SPI R/W into > + * the drivers, but they also must manage this lock themselves. > + */ > struct mutex state_lock; > struct spi_message msg; > struct spi_transfer *xfer;