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,URIBL_BLOCKED,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 E1AC4C35656 for ; Fri, 21 Feb 2020 13:14:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AFA1E24650 for ; Fri, 21 Feb 2020 13:14:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582290891; bh=zLeMnqmezs9X0Xy259yO8BM4pOGYsFwjR8qRbebbfLM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=gKgUCq3WCEoD4H2y9BJbCe5OTBjzUdq1xIVkPWk5+6wGl/jsExtULFd82rY8UbESe r147WqKFU3yIo+XZmhCw97gxag1XVp1YbgbndIu87LWtFG5rthTWivXW0uuD15nNhC cCGT1oRsQzIxZBtQBhhZj7XKntrsraiOPX8J2Rr8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728086AbgBUNOv (ORCPT ); Fri, 21 Feb 2020 08:14:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:45344 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727039AbgBUNOv (ORCPT ); Fri, 21 Feb 2020 08:14:51 -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 ED9652073A; Fri, 21 Feb 2020 13:14:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582290890; bh=zLeMnqmezs9X0Xy259yO8BM4pOGYsFwjR8qRbebbfLM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=ph+4u/BXZz9G+9Ax45OcrnZ6Q3noZzZboM+ugFYchqZECl91wxBnYOWbCmuD/1iG5 B60w7GPnuZyJ9MkLPkqRzo50/5nh58WDhZ2js4VxxoU158CB6GgZds6bPvK+HQ8C8N pKP/8TvqCJmt7TTZbCDC5ceDquRVMozitmDpU87M= Date: Fri, 21 Feb 2020 13:14:46 +0000 From: Jonathan Cameron To: Alexandru Ardelean Cc: , Subject: Re: [PATCH 3/3] iio: imu: adis: add a note better explaining state_lock Message-ID: <20200221131446.20363088@archlinux> In-Reply-To: <20200221114943.2056-3-alexandru.ardelean@analog.com> References: <20200221114943.2056-1-alexandru.ardelean@analog.com> <20200221114943.2056-3-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 Fri, 21 Feb 2020 13:49:43 +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. Nice work. Will pick up in v2. Thanks, Jonathan > > Signed-off-by: Alexandru Ardelean > --- > 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 11c915b61ae2..a3110c097fa1 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;