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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6FB9CC4332F for ; Mon, 8 Nov 2021 18:42:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5505C60232 for ; Mon, 8 Nov 2021 18:42:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235792AbhKHSpI (ORCPT ); Mon, 8 Nov 2021 13:45:08 -0500 Received: from mga18.intel.com ([134.134.136.126]:65325 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235795AbhKHSpG (ORCPT ); Mon, 8 Nov 2021 13:45:06 -0500 X-IronPort-AV: E=McAfee;i="6200,9189,10162"; a="219201068" X-IronPort-AV: E=Sophos;i="5.87,218,1631602800"; d="scan'208";a="219201068" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 08 Nov 2021 10:42:20 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,218,1631602800"; d="scan'208";a="503150689" Received: from maru.jf.intel.com ([10.54.51.77]) by orsmga008.jf.intel.com with ESMTP; 08 Nov 2021 10:42:20 -0800 From: jae.hyun.yoo@intel.com To: Rob Herring , Corey Minyard , Joel Stanley , Andrew Jeffery , Cedric Le Goater , Haiyue Wang , ChiaWei Wang , Jae Hyun Yoo Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, openipmi-developer@lists.sourceforge.net Subject: [PATCH v3 3/6] ipmi: bt: add clock control logic Date: Mon, 8 Nov 2021 11:01:57 -0800 Message-Id: <20211108190200.290957-4-jae.hyun.yoo@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211108190200.290957-1-jae.hyun.yoo@intel.com> References: <20211108190200.290957-1-jae.hyun.yoo@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Jae Hyun Yoo If LPC BT driver is registered ahead of lpc-ctrl module, LPC BT hardware block will be enabled without heart beating of LCLK until lpc-ctrl enables the LCLK. This issue causes improper handling on host interrupts when the host sends interrupts in that time frame. Then kernel eventually forcibly disables the interrupt with dumping stack and printing a 'nobody cared this irq' message out. To prevent this issue, all LPC sub drivers should enable LCLK individually so this patch adds clock control logic into the LPC BT driver. Note: dtsi change in this patch series should be applied along with, and dtbs should be re-compiled after applying this series since it's adding a new required property otherwise this driver will not be probed correctly. Fixes: 54f9c4d0778b ("ipmi: add an Aspeed BT IPMI BMC driver") Signed-off-by: Jae Hyun Yoo Reviewed-by: Joel Stanley Reviewed-by: Cédric Le Goater Reviewed-by: Andrew Jeffery --- v2 -> v3: * Simplified the -EPROBE_DEFER handling using dev_err_probe(). v1 -> v2: * No change. drivers/char/ipmi/bt-bmc.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/drivers/char/ipmi/bt-bmc.c b/drivers/char/ipmi/bt-bmc.c index 7450904e330a..f6547ddd7284 100644 --- a/drivers/char/ipmi/bt-bmc.c +++ b/drivers/char/ipmi/bt-bmc.c @@ -5,6 +5,7 @@ #include #include +#include #include #include #include @@ -62,6 +63,7 @@ struct bt_bmc { wait_queue_head_t queue; struct timer_list poll_timer; struct mutex mutex; + struct clk *clk; }; static atomic_t open_count = ATOMIC_INIT(0); @@ -423,6 +425,16 @@ static int bt_bmc_probe(struct platform_device *pdev) if (IS_ERR(bt_bmc->base)) return PTR_ERR(bt_bmc->base); + bt_bmc->clk = devm_clk_get(dev, NULL); + if (IS_ERR(bt_bmc->clk)) + return dev_err_probe(dev, PTR_ERR(bt_bmc->clk), + "Unable to get clock\n"); + rc = clk_prepare_enable(bt_bmc->clk); + if (rc) { + dev_err(dev, "Unable to enable clock\n"); + return rc; + } + mutex_init(&bt_bmc->mutex); init_waitqueue_head(&bt_bmc->queue); @@ -433,7 +445,7 @@ static int bt_bmc_probe(struct platform_device *pdev) rc = misc_register(&bt_bmc->miscdev); if (rc) { dev_err(dev, "Unable to register misc device\n"); - return rc; + goto err; } bt_bmc_config_irq(bt_bmc, pdev); @@ -457,6 +469,11 @@ static int bt_bmc_probe(struct platform_device *pdev) clr_b_busy(bt_bmc); return 0; + +err: + clk_disable_unprepare(bt_bmc->clk); + + return rc; } static int bt_bmc_remove(struct platform_device *pdev) @@ -466,6 +483,8 @@ static int bt_bmc_remove(struct platform_device *pdev) misc_deregister(&bt_bmc->miscdev); if (bt_bmc->irq < 0) del_timer_sync(&bt_bmc->poll_timer); + clk_disable_unprepare(bt_bmc->clk); + return 0; } -- 2.25.1