From patchwork Wed Sep 20 18:59:55 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wolfram Sang X-Patchwork-Id: 9962649 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 8C6FF60208 for ; Wed, 20 Sep 2017 21:42:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7E92B29225 for ; Wed, 20 Sep 2017 21:42:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 72CA12926B; Wed, 20 Sep 2017 21:42:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 0CD1C2925E for ; Wed, 20 Sep 2017 21:42:05 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E73CE6E7E2; Wed, 20 Sep 2017 21:41:10 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from pokefinder.org (sauhun.de [88.99.104.3]) by gabe.freedesktop.org (Postfix) with ESMTP id BED346E19C for ; Wed, 20 Sep 2017 19:00:04 +0000 (UTC) Received: from localhost (p54B332E6.dip0.t-ipconnect.de [84.179.50.230]) by pokefinder.org (Postfix) with ESMTPSA id 1A6842C43A8; Wed, 20 Sep 2017 21:00:04 +0200 (CEST) From: Wolfram Sang To: linux-i2c@vger.kernel.org Subject: [RFC PATCH v5 5/6] i2c: rcar: skip DMA if buffer is not safe Date: Wed, 20 Sep 2017 20:59:55 +0200 Message-Id: <20170920185956.13874-6-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170920185956.13874-1-wsa+renesas@sang-engineering.com> References: <20170920185956.13874-1-wsa+renesas@sang-engineering.com> X-Mailman-Approved-At: Wed, 20 Sep 2017 21:41:09 +0000 Cc: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-renesas-soc@vger.kernel.org, Wolfram Sang , linux-input@vger.kernel.org, linux-media@vger.kernel.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP This HW is prone to races, so it needs to setup new messages in irq context. That means we can't alloc bounce buffers if a message buffer is not DMA safe. So, in that case, simply fall back to PIO. Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-rcar.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index 15d764afec3b29..8a2ae3e6c561c4 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -359,7 +359,7 @@ static void rcar_i2c_dma(struct rcar_i2c_priv *priv) int len; /* Do not use DMA if it's not available or for messages < 8 bytes */ - if (IS_ERR(chan) || msg->len < 8) + if (IS_ERR(chan) || msg->len < 8 || !(msg->flags & I2C_M_DMA_SAFE)) return; if (read) {