From patchwork Wed Dec 2 23:40:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bhaumik Bhatt X-Patchwork-Id: 11947339 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=-11.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 AC0CFC6369E for ; Wed, 2 Dec 2020 23:42:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5BFE422203 for ; Wed, 2 Dec 2020 23:42:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729147AbgLBXmE (ORCPT ); Wed, 2 Dec 2020 18:42:04 -0500 Received: from m42-5.mailgun.net ([69.72.42.5]:28012 "EHLO m42-5.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728532AbgLBXmE (ORCPT ); Wed, 2 Dec 2020 18:42:04 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1606952500; h=Message-Id: Date: Subject: Cc: To: From: Sender; bh=ML0k+1w1cdrfiotHpg1TRWJI765NDUhymPNfbEq4eJU=; b=kHL+TMyZP1suObWxX0VxphkdWEePRsaTPC1aYFeaXC7JOWxaasNv7LuIIdcHo9XQ2vXb/44e B6FSgCcIGvRvJQ/TlRKOzV5VG0BSvyFbatHfyjup7KzQTEvqyIp+bZON13RlsG2lvkKkG0hS 42GFd4Tf2Q3OuTIinYpUU4WZhtI= X-Mailgun-Sending-Ip: 69.72.42.5 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n01.prod.us-west-2.postgun.com with SMTP id 5fc8260107535c81bad66130 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 02 Dec 2020 23:40:49 GMT Sender: bbhatt=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 4AE22C43462; Wed, 2 Dec 2020 23:40:49 +0000 (UTC) Received: from malabar-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: bbhatt) by smtp.codeaurora.org (Postfix) with ESMTPSA id 561D0C433ED; Wed, 2 Dec 2020 23:40:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 561D0C433ED Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=bbhatt@codeaurora.org From: Bhaumik Bhatt To: manivannan.sadhasivam@linaro.org, hemantk@codeaurora.org Cc: linux-arm-msm@vger.kernel.org, loic.poulain@linaro.org, jhugo@codeaurora.org, linux-kernel@vger.kernel.org, Bhaumik Bhatt Subject: [PATCH v3 0/7] Updates to MHI channel handling Date: Wed, 2 Dec 2020 15:40:31 -0800 Message-Id: <1606952438-15321-1-git-send-email-bbhatt@codeaurora.org> X-Mailer: git-send-email 2.7.4 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org MHI specification shows a state machine with support for STOP channel command and the validity of certain state transitions. MHI host currently does not provide any mechanism to stop a channel and restart it without resetting it. There are also times when the device moves on to a different execution environment while client drivers on the host are unaware of it and still attempt to reset the channels facing unnecessary timeouts. This series addresses the above areas to provide support for stopping an MHI channel, resuming it back, improved documentation and improving upon channel state machine handling in general. This set of patches was tested on arm64 architecture. v3: -Updated documentation for channel transfer APIs to highlight differences -Create separate patch for "allowing channel to be disabled from stopped state" v2: -Renamed the newly introduced APIs to mhi_start_transfer() / mhi_stop_transfer() -Added improved documentation to avoid confusion with the new APIs -Removed the __ prefix from mhi_unprepare_channel() API for consistency. Bhaumik Bhatt (7): bus: mhi: core: Allow receiving a STOP channel command response bus: mhi: core: Allow channel to be disabled from stopped state bus: mhi: core: Improvements to the channel handling state machine bus: mhi: core: Add support to stop or start channel data transfers bus: mhi: core: Check execution environment for channel before issuing reset bus: mhi: core: Remove __ prefix for MHI channel unprepare function bus: mhi: Improve documentation on channel transfer setup APIs drivers/bus/mhi/core/init.c | 9 +- drivers/bus/mhi/core/internal.h | 12 +++ drivers/bus/mhi/core/main.c | 229 +++++++++++++++++++++++++++------------- include/linux/mhi.h | 45 +++++++- 4 files changed, 220 insertions(+), 75 deletions(-)