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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C892DC4332F for ; Wed, 16 Nov 2022 09:03:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229862AbiKPJDa (ORCPT ); Wed, 16 Nov 2022 04:03:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55614 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238832AbiKPJDN (ORCPT ); Wed, 16 Nov 2022 04:03:13 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A227411C2B for ; Wed, 16 Nov 2022 01:02:35 -0800 (PST) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ovEJV-0000py-NE; Wed, 16 Nov 2022 10:02:33 +0100 Received: from ore by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1ovEJU-0006vu-KQ; Wed, 16 Nov 2022 10:02:32 +0100 Date: Wed, 16 Nov 2022 10:02:32 +0100 From: Oleksij Rempel To: Andrew Lunn Cc: linux-i2c@vger.kernel.org, Oleksij Rempel , kernel@pengutronix.de, Shawn Guo , Sascha Hauer , Fabio Estevam Subject: Re: [PATCH] i2c: imx: Only DMA messages with I2C_M_DMA_SAFE flag set Message-ID: <20221116090232.GA12278@pengutronix.de> References: <20221109235902.468723-1-andrew@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20221109235902.468723-1-andrew@lunn.ch> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-Accept-Language: de,en X-Accept-Content-Type: text/plain User-Agent: Mutt/1.10.1 (2018-07-13) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: ore@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-i2c@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org On Thu, Nov 10, 2022 at 12:59:02AM +0100, Andrew Lunn wrote: > Recent changes to the DMA code has resulting in the IMX driver failing > I2C transfers when the buffer has been vmalloc. Only perform DMA > transfers if the message has the I2C_M_DMA_SAFE flag set, indicating > the client is providing a buffer which is DMA safe. > > This is a minimal fix for stable. The I2C core provides helpers to > allocate a bounce buffer. For a fuller fix the master should make use > of these helpers. > > Fixes: 4544b9f25e70 ("dma-mapping: Add vmap checks to dma_map_single()") > Signed-off-by: Andrew Lunn Acked-by: Oleksij Rempel > --- > drivers/i2c/busses/i2c-imx.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c > index 3082183bd66a..fc70920c4dda 100644 > --- a/drivers/i2c/busses/i2c-imx.c > +++ b/drivers/i2c/busses/i2c-imx.c > @@ -1132,7 +1132,8 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, > int i, result; > unsigned int temp; > int block_data = msgs->flags & I2C_M_RECV_LEN; > - int use_dma = i2c_imx->dma && msgs->len >= DMA_THRESHOLD && !block_data; > + int use_dma = i2c_imx->dma && msgs->flags & I2C_M_DMA_SAFE && > + msgs->len >= DMA_THRESHOLD && !block_data; > > dev_dbg(&i2c_imx->adapter.dev, > "<%s> write slave address: addr=0x%x\n", > @@ -1298,7 +1299,8 @@ static int i2c_imx_xfer_common(struct i2c_adapter *adapter, > result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg, atomic); > } else { > if (!atomic && > - i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD) > + i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD && > + msgs[i].flags & I2C_M_DMA_SAFE) > result = i2c_imx_dma_write(i2c_imx, &msgs[i]); > else > result = i2c_imx_write(i2c_imx, &msgs[i], atomic); > -- > 2.37.2 > > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |