From patchwork Mon Oct 29 21:14:09 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jae Hyun Yoo X-Patchwork-Id: 10660211 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E23A213B5 for ; Mon, 29 Oct 2018 21:15:58 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D262D28EC7 for ; Mon, 29 Oct 2018 21:15:58 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C69832903F; Mon, 29 Oct 2018 21:15:58 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 4E51B28EC7 for ; Mon, 29 Oct 2018 21:15:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=6sLsmLY0uqH+lYaHCB92/6oNJEVu4neCnUIS9i9kCuQ=; b=LaWAljhjwLzxkL Ceo/wdJ59ut88ieDLrNW516utTS61dK94DGV2Pu23VtTpgyDPo0yfU8nzscGMdyzHUs+6cnPM7IP8 h+Nd8eloe96od6OoIM8IKsbNKC57azW+YU4Xxy1K4C8ddiQ30JSWEK/948nB5pSqJa1LTdYI4Kuf2 1bI9CsACH9D9bXxRSQKXQdWmoMNJ5ehX8MkH0fnXx/nN19tUO9AJilaLO/IBGjFWQyv/lCOqcJSZk gaUolAEAvr3lHm1cUEmXnSha2vx/dKaZM+Yqvs1F/u6iJ8celfssQb0/2xIxxeH2lFMhJwBqT/Vcp a29SH9M99z8auYaWX2JA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gHEsx-0003KP-3w; Mon, 29 Oct 2018 21:15:43 +0000 Received: from mga14.intel.com ([192.55.52.115]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gHEs8-0001iC-V5 for linux-arm-kernel@lists.infradead.org; Mon, 29 Oct 2018 21:14:54 +0000 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 29 Oct 2018 14:14:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,441,1534834800"; d="scan'208";a="275455989" Received: from maru.jf.intel.com ([10.54.51.77]) by fmsmga005.fm.intel.com with ESMTP; 29 Oct 2018 14:14:38 -0700 From: Jae Hyun Yoo To: Wolfram Sang , Brendan Higgins , Rob Herring , Joel Stanley , Benjamin Herrenschmidt , Mark Rutland , Andrew Jeffery , linux-i2c@vger.kernel.org, openbmc@lists.ozlabs.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: [PATCH i2c-next v8 0/5] i2c: aspeed: Add bus idle waiting logic for multi-master use cases Date: Mon, 29 Oct 2018 14:14:09 -0700 Message-Id: <20181029211414.20771-1-jae.hyun.yoo@linux.intel.com> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181029_141453_041459_4DB335DA X-CRM114-Status: GOOD ( 13.77 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Vernon Mauery , Jae Hyun Yoo , Jarkko Nikula , James Feist Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP In multi-master environment, this driver's master cannot know exactly when a peer master sends data to this driver's slave so a case can be happened that this master tries to send data through the master_xfer function but slave data from peer master is still being processed by this driver. To prevent state corruption in the case, this patch adds checking code if any slave operation is ongoing and it waits up to the bus timeout duration before starting a master_xfer operation. To support this change, it introduces changes on i2c-core-base to make that able to read the bus timeout and master transfer retries count values from device tree properties. Please review this patch set. Thanks, -Jae Changes since v7: - Simplified the bus idle waiting logic using jiffy based timer APIs. Changes since v6: - Changed the 'timeout-ms' property name to 'bus-timeout-ms'. Changes since v5: - Changed using of property reading API to device_property_read_u32. Changes since v4: - Moved the property reading code into i2c-base-core and changed the property name to 'timeout-ms'. Also, added '#retries' property reading code. - Changed bus busy checking logic to make that check slave_state instead of 'Transfer Mode State Machine' reg value. Changes since v3: - Changed the property name to 'timeout' and made it use the default setting in i2c-core when not specified. Changes since v2: - Changed the property name to 'aspeed,timeout' and made it to update the adapter's timeout configuration. Changes since v1: - Changed define names of timeout related. Jae Hyun Yoo (5): dt-bindings: i2c: Add 'bus-timeout-ms' and '#retries' properties as common optional i2c: core: Add support reading of 'bus-timeout-ms' and '#retries' properties dt-bindings: i2c: aspeed: Add 'bus-timeout-ms' property as an optional property i2c: aspeed: Remove hard-coded bus timeout value setting i2c: aspeed: Add bus idle waiting logic for multi-master use cases .../devicetree/bindings/i2c/i2c-aspeed.txt | 3 ++ Documentation/devicetree/bindings/i2c/i2c.txt | 6 +++ drivers/i2c/busses/i2c-aspeed.c | 53 +++++++++++++------ drivers/i2c/i2c-core-base.c | 12 ++++- 4 files changed, 56 insertions(+), 18 deletions(-)