From patchwork Fri Dec 4 01:23:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bhaumik Bhatt X-Patchwork-Id: 11950367 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 7C3BCC197BF for ; Fri, 4 Dec 2020 01:24:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4FA8A224F4 for ; Fri, 4 Dec 2020 01:24:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732001AbgLDBYp (ORCPT ); Thu, 3 Dec 2020 20:24:45 -0500 Received: from m43-15.mailgun.net ([69.72.43.15]:35300 "EHLO m43-15.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389548AbgLDBY3 (ORCPT ); Thu, 3 Dec 2020 20:24:29 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1607045050; h=Message-Id: Date: Subject: Cc: To: From: Sender; bh=qLA3LpoWylWR06vLJtM3NiGDbgNo/hzbOnZhqJLxv1Y=; b=pgUau7lyAvsUWGQ826Olq6JUGiBFbOYQIkiFlju3uWiWpmjhW9BmODkf3d5qmDeR2r2BVXGs +qCetZ45MPBB3LnDpe4J2dl0SOLVLHA3HO38mP22IxauVJn5AWtLswZWpnv28y+Vb8uWeHld jNx9cGU6Pu2Erw5YnfJjSRNkTss= X-Mailgun-Sending-Ip: 69.72.43.15 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 5fc98f8ef06acf11ab44478a (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Fri, 04 Dec 2020 01:23:26 GMT Sender: bbhatt=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 96F8CC43463; Fri, 4 Dec 2020 01:23:26 +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 8EDC7C433CA; Fri, 4 Dec 2020 01:23:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 8EDC7C433CA 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 v4 0/8] Updates to MHI channel handling Date: Thu, 3 Dec 2020 17:23:09 -0800 Message-Id: <1607044997-19577-1-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. v4: -Updated commit text/descriptions and addressed checkpatch checks -Added context validity check before starting/stopping channels from new API -Added patch to clear channel context configuration after reset/unprepare 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 (8): bus: mhi: core: Allow sending the STOP channel command bus: mhi: core: Allow channel to be disabled from stopped state bus: mhi: core: Improvements to the channel handling state machine bus: mhi: core: Clear configuration from channel context during reset bus: mhi: core: Add support to stop or start channel data transfers bus: mhi: core: Check channel execution environment 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 | 22 +++- drivers/bus/mhi/core/internal.h | 12 ++ drivers/bus/mhi/core/main.c | 238 ++++++++++++++++++++++++++++------------ include/linux/mhi.h | 45 +++++++- 4 files changed, 242 insertions(+), 75 deletions(-)