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=-10.1 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,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 9FA4BC352AA for ; Tue, 1 Oct 2019 16:59:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 755AC21783 for ; Tue, 1 Oct 2019 16:59:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569949189; bh=aH6ctXhIndO4xFNADjyeEW+RHGG7RRX4yg9ZHsOaVNw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=e0JSctDdZ4D+lS0tf1sOEn8pGvkJCM87NV2HPHTY6Sd8TVMbsDjYwaeODrwQX25QP +N7JxEvCijTYIYym/cOyaCpgfFUKDaIC/7r2/dkv9AXDy8ZNRfvIQbF8UtWEtvlg4y r0dJrKpZt1DUcGWZBXEOMfNGMYU/Xrqr7L1Pu/ak= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730616AbfJAQlG (ORCPT ); Tue, 1 Oct 2019 12:41:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:52384 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730481AbfJAQk5 (ORCPT ); Tue, 1 Oct 2019 12:40:57 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 49DDD2070B; Tue, 1 Oct 2019 16:40:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569948057; bh=aH6ctXhIndO4xFNADjyeEW+RHGG7RRX4yg9ZHsOaVNw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rHIKX/z1jd2pgw/lcnulGZQn65TrsM/IkOUxt9b4r3mgK/oEE0/Qb8+iOYngC65bh Vnc0JtnOq8cP5lqwy77JyCLUFsHHhQ0aOc1SjUNqQU2pAlZi527yw2plN7A29MsiAY r2+KMvAzGZ5eobSpzu4/dJreF8V8RK/T8QScqToA= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Lee Jones , Bjorn Andersson , Wolfram Sang , Sasha Levin , linux-i2c@vger.kernel.org, linux-arm-msm@vger.kernel.org Subject: [PATCH AUTOSEL 5.3 58/71] i2c: qcom-geni: Disable DMA processing on the Lenovo Yoga C630 Date: Tue, 1 Oct 2019 12:39:08 -0400 Message-Id: <20191001163922.14735-58-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191001163922.14735-1-sashal@kernel.org> References: <20191001163922.14735-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Lee Jones [ Upstream commit 127068abe85bf3dee50df51cb039a5a987a4a666 ] We have a production-level laptop (Lenovo Yoga C630) which is exhibiting a rather horrific bug. When I2C HID devices are being scanned for at boot-time the QCom Geni based I2C (Serial Engine) attempts to use DMA. When it does, the laptop reboots and the user never sees the OS. Attempts are being made to debug the reason for the spontaneous reboot. No luck so far, hence the requirement for this hot-fix. This workaround will be removed once we have a viable fix. Signed-off-by: Lee Jones Tested-by: Bjorn Andersson Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-qcom-geni.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index a89bfce5388ee..17abf60c94aeb 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -355,11 +355,13 @@ static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, { dma_addr_t rx_dma; unsigned long time_left; - void *dma_buf; + void *dma_buf = NULL; struct geni_se *se = &gi2c->se; size_t len = msg->len; - dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); + if (!of_machine_is_compatible("lenovo,yoga-c630")) + dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); + if (dma_buf) geni_se_select_mode(se, GENI_SE_DMA); else @@ -394,11 +396,13 @@ static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, { dma_addr_t tx_dma; unsigned long time_left; - void *dma_buf; + void *dma_buf = NULL; struct geni_se *se = &gi2c->se; size_t len = msg->len; - dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); + if (!of_machine_is_compatible("lenovo,yoga-c630")) + dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); + if (dma_buf) geni_se_select_mode(se, GENI_SE_DMA); else -- 2.20.1