From patchwork Sat Nov 4 20:20:05 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wolfram Sang X-Patchwork-Id: 45324 Received: from vger.kernel.org ([209.132.180.67]) by www.linuxtv.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eB4ya-0001l8-44; Sat, 04 Nov 2017 20:23:32 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752704AbdKDUXP (ORCPT + 1 other); Sat, 4 Nov 2017 16:23:15 -0400 Received: from sauhun.de ([88.99.104.3]:44820 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751733AbdKDUU1 (ORCPT ); Sat, 4 Nov 2017 16:20:27 -0400 Received: from localhost (p54B33782.dip0.t-ipconnect.de [84.179.55.130]) by pokefinder.org (Postfix) with ESMTPSA id DB7302C35B4; Sat, 4 Nov 2017 21:20:23 +0100 (CET) From: Wolfram Sang To: linux-i2c@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-iio@vger.kernel.org, linux-input@vger.kernel.org, linux-media@vger.kernel.org, Mark Brown , Wolfram Sang Subject: [PATCH v6 5/9] i2c: add i2c_master_{send|recv}_dmasafe Date: Sat, 4 Nov 2017 21:20:05 +0100 Message-Id: <20171104202009.3818-6-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20171104202009.3818-1-wsa+renesas@sang-engineering.com> References: <20171104202009.3818-1-wsa+renesas@sang-engineering.com> Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Use the new helper to create variants of i2c_master_{send|recv} which mark their buffers as DMA safe. Signed-off-by: Wolfram Sang Acked-by: Jonathan Cameron --- include/linux/i2c.h | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/include/linux/i2c.h b/include/linux/i2c.h index ef1a8791c1ae24..8c144e3cbfb261 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -81,6 +81,22 @@ static inline int i2c_master_recv(const struct i2c_client *client, }; /** + * i2c_master_recv_dmasafe - issue a single I2C message in master receive mode + * using a DMA safe buffer + * @client: Handle to slave device + * @buf: Where to store data read from slave, must be safe to use with DMA + * @count: How many bytes to read, must be less than 64k since msg.len is u16 + * + * Returns negative errno, or else the number of bytes read. + */ +static inline int i2c_master_recv_dmasafe(const struct i2c_client *client, + char *buf, int count) +{ + return i2c_transfer_buffer_flags(client, buf, count, + I2C_M_RD | I2C_M_DMA_SAFE); +}; + +/** * i2c_master_send - issue a single I2C message in master transmit mode * @client: Handle to slave device * @buf: Data that will be written to the slave @@ -93,6 +109,21 @@ static inline int i2c_master_send(const struct i2c_client *client, { return i2c_transfer_buffer_flags(client, (char *)buf, count, 0); }; +/** + * i2c_master_send_dmasafe - issue a single I2C message in master transmit mode + * using a DMA safe buffer + * @client: Handle to slave device + * @buf: Data that will be written to the slave, must be safe to use with DMA + * @count: How many bytes to write, must be less than 64k since msg.len is u16 + * + * Returns negative errno, or else the number of bytes written. + */ +static inline int i2c_master_send_dmasafe(const struct i2c_client *client, + const char *buf, int count) +{ + return i2c_transfer_buffer_flags(client, (char *)buf, count, + I2C_M_DMA_SAFE); +}; /* Transfer num messages. */