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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B4965C4360F for ; Wed, 3 Apr 2019 12:41:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D5B22084C for ; Wed, 3 Apr 2019 12:41:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726968AbfDCMlJ (ORCPT ); Wed, 3 Apr 2019 08:41:09 -0400 Received: from sauhun.de ([88.99.104.3]:48410 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726723AbfDCMkm (ORCPT ); Wed, 3 Apr 2019 08:40:42 -0400 Received: from localhost (p54B3311F.dip0.t-ipconnect.de [84.179.49.31]) by pokefinder.org (Postfix) with ESMTPSA id 81A513E43D1; Wed, 3 Apr 2019 14:40:40 +0200 (CEST) From: Wolfram Sang To: linux-i2c@vger.kernel.org Cc: linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Peter Rosin , Stefan Lengfeld , linux-omap@vger.kernel.org, linux-tegra@vger.kernel.org, Linus Walleij , Andy Shevchenko , Wolfram Sang Subject: [PATCH 11/12] i2c: algo: bit: add flag to whitelist atomic transfers Date: Wed, 3 Apr 2019 14:40:18 +0200 Message-Id: <20190403124019.8947-12-wsa+renesas@sang-engineering.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190403124019.8947-1-wsa+renesas@sang-engineering.com> References: <20190403124019.8947-1-wsa+renesas@sang-engineering.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use the new xfer_atomic callback to check a newly introduced flag to whitelist atomic transfers. This will report configurations which worked accidently. Signed-off-by: Wolfram Sang --- drivers/i2c/algos/i2c-algo-bit.c | 22 ++++++++++++++++++++-- include/linux/i2c-algo-bit.h | 1 + 2 files changed, 21 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/algos/i2c-algo-bit.c b/drivers/i2c/algos/i2c-algo-bit.c index 5e5990a83da5..913db013fe90 100644 --- a/drivers/i2c/algos/i2c-algo-bit.c +++ b/drivers/i2c/algos/i2c-algo-bit.c @@ -603,6 +603,23 @@ static int bit_xfer(struct i2c_adapter *i2c_adap, return ret; } +/* + * We print a warning when we are not flagged to support atomic transfers but + * will try anyhow. That's what the I2C core would do as well. Sadly, we can't + * modify the algorithm struct at probe time because this struct is exported + * 'const'. + */ +static int bit_xfer_atomic(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], + int num) +{ + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + if (!adap->can_do_atomic) + dev_warn(&i2c_adap->dev, "not flagged for atomic transfers\n"); + + return bit_xfer(i2c_adap, msgs, num); +} + static u32 bit_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | I2C_FUNC_NOSTART | I2C_FUNC_SMBUS_EMUL | @@ -615,8 +632,9 @@ static u32 bit_func(struct i2c_adapter *adap) /* -----exported algorithm data: ------------------------------------- */ const struct i2c_algorithm i2c_bit_algo = { - .master_xfer = bit_xfer, - .functionality = bit_func, + .master_xfer = bit_xfer, + .master_xfer_atomic = bit_xfer_atomic, + .functionality = bit_func, }; EXPORT_SYMBOL(i2c_bit_algo); diff --git a/include/linux/i2c-algo-bit.h b/include/linux/i2c-algo-bit.h index 69045df78e2d..7fd5575a368f 100644 --- a/include/linux/i2c-algo-bit.h +++ b/include/linux/i2c-algo-bit.h @@ -33,6 +33,7 @@ struct i2c_algo_bit_data { minimum 5 us for standard-mode I2C and SMBus, maximum 50 us for SMBus */ int timeout; /* in jiffies */ + bool can_do_atomic; /* callbacks don't sleep, we can be atomic */ }; int i2c_bit_add_bus(struct i2c_adapter *); -- 2.11.0