From patchwork Thu Aug 17 14:14:48 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wolfram Sang X-Patchwork-Id: 43275 Received: from vger.kernel.org ([209.132.180.67]) by www.linuxtv.org with esmtp (Exim 4.84_2) (envelope-from ) id 1diLaw-0004a8-AU; Thu, 17 Aug 2017 14:16:22 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752932AbdHQOPu (ORCPT + 1 other); Thu, 17 Aug 2017 10:15:50 -0400 Received: from sauhun.de ([88.99.104.3]:59953 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753165AbdHQOO5 (ORCPT ); Thu, 17 Aug 2017 10:14:57 -0400 Received: from localhost (p54B3365B.dip0.t-ipconnect.de [84.179.54.91]) by pokefinder.org (Postfix) with ESMTPSA id 1EF002C2F95; Thu, 17 Aug 2017 16:14:54 +0200 (CEST) From: Wolfram Sang To: linux-i2c@vger.kernel.org Cc: linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, linux-input@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, Wolfram Sang Subject: [RFC PATCH v4 5/6] i2c: rcar: skip DMA if buffer is not safe Date: Thu, 17 Aug 2017 16:14:48 +0200 Message-Id: <20170817141449.23958-6-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170817141449.23958-1-wsa+renesas@sang-engineering.com> References: <20170817141449.23958-1-wsa+renesas@sang-engineering.com> Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org 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 93c1a54981df08..5654a7142bffec 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) {