From patchwork Thu Sep 5 14:41:22 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lee Jones X-Patchwork-Id: 11133233 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C521A1395 for ; Thu, 5 Sep 2019 14:41:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E20CD206BA for ; Thu, 5 Sep 2019 14:41:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="mB3Sko2i" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388300AbfIEOl2 (ORCPT ); Thu, 5 Sep 2019 10:41:28 -0400 Received: from mail-wm1-f47.google.com ([209.85.128.47]:53077 "EHLO mail-wm1-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730622AbfIEOl1 (ORCPT ); Thu, 5 Sep 2019 10:41:27 -0400 Received: by mail-wm1-f47.google.com with SMTP id t17so3123151wmi.2 for ; Thu, 05 Sep 2019 07:41:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id; bh=gvXZWVwHpbdck37kQtyWXbSqSEeeYIFeArcoXQY5L9I=; b=mB3Sko2ifz0tOSCJAHjX283XAID1lWJHxJ8+5TDxf+6IIqPTfr+z/PPEttOLXQQH+b 8VhpLSs2Xx38CdkqQN3H01l2xCICqrXkssFgkSPUbXJ7w82PFNTO/EflDqdaBZrjTBr4 OPh0RTFzOYZ9LW56DmIi7VmHRBlGKptwDvVx48791iI0/CHvG7SloF7JfIgzVPVxd9SI Rs/Blwyl15h0QvyK0ESbbrFGhGmV1HOpEJtqRhDWTDXP8pDPRI+cycCzopj1+4fHb/Dm IQ1Epwi19TWJKlDbg2Ewvh51NYJmGcEGrfcOJBcKHYIVsbxVndIy9Vz+arcpx4sv7wik J4KQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=gvXZWVwHpbdck37kQtyWXbSqSEeeYIFeArcoXQY5L9I=; b=gIppG5BF0yKUTaOC0YjqWVn4c6zwen7MRtmq+KqrU5KUzUzvNZ5ni4czN8rS/BXAnp Krlulgf7szd8bAuOhSDOzu1y65LnwpcsYGtVsHsXKj6WA6Mdl+y/+ONCQKYG+ym6Oc/h KLa6wEqcnm9SNFAyiiIKSH/j98+YPBrMDz2l+LB/0KQsI4qM4tfvv8HuYi7qdnSzGsTB /f6e1RaHt2vG7tac71UY/W0VBQYeOlWTghd1Ie3/BERXUtV8gcIzbB2MgiIOcvcxkN/P CK0Fy9yXqKmESTb8iJplO34OFR3Tjecb1LEfaQAK9Wz3U+pEMtxdR3fO68YjegtCPE2F axeg== X-Gm-Message-State: APjAAAUAE1CxkGbjytxMyA+MThJYOoirzIW+xkItgSC26dViNjOSLJz6 ECpgadr2jGUrJhGsHygUxz+7lg== X-Google-Smtp-Source: APXvYqwSsdzWd7u9Fz8nhhPSzaTVwwrjIYP4HGLSO8rAw+8XajRcLI9Thgj6+E2e/hZXiqvdsbjQ7w== X-Received: by 2002:a1c:be04:: with SMTP id o4mr3387448wmf.60.1567694485991; Thu, 05 Sep 2019 07:41:25 -0700 (PDT) Received: from localhost.localdomain ([95.147.198.36]) by smtp.gmail.com with ESMTPSA id c132sm4191392wme.27.2019.09.05.07.41.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 Sep 2019 07:41:25 -0700 (PDT) From: Lee Jones To: alokc@codeaurora.org, agross@kernel.org, robh+dt@kernel.org, mark.rutland@arm.com, bjorn.andersson@linaro.org, vkoul@kernel.org, wsa@the-dreams.de Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, Lee Jones Subject: [RESEND v3 1/1] i2c: qcom-geni: Provide an option to disable DMA processing Date: Thu, 5 Sep 2019 15:41:22 +0100 Message-Id: <20190905144122.5689-1-lee.jones@linaro.org> X-Mailer: git-send-email 2.17.1 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org 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. Signed-off-by: Lee Jones --- 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 a89bfce5388e..17abf60c94ae 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