From patchwork Tue Aug 22 05:45:18 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heiner Kallweit X-Patchwork-Id: 804276 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-i2c-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="QAPgfn7o"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3xbzzs1lDkz9t24 for ; Tue, 22 Aug 2017 15:45:29 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754506AbdHVFp1 (ORCPT ); Tue, 22 Aug 2017 01:45:27 -0400 Received: from mail-wr0-f196.google.com ([209.85.128.196]:34664 "EHLO mail-wr0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754495AbdHVFp1 (ORCPT ); Tue, 22 Aug 2017 01:45:27 -0400 Received: by mail-wr0-f196.google.com with SMTP id p14so15497052wrg.1 for ; Mon, 21 Aug 2017 22:45:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:subject:to:cc:message-id:date:user-agent:mime-version :content-transfer-encoding; bh=FuVAJDlJKROQjGwF4tEeY7rvSS85Zas131f4yIJkyPM=; b=QAPgfn7oaeraAGYlbYTCZWnimX7j6ZZ2hSLn7u0Y7oYCRmFTSOIo1uXpbc+1pgpW1V E+WbWQFtQywDMdguih+/+/nOUQH7iOfgVy5vaZYmEmem327GTXSqfs19gHHRVwmXTGSX SFlPLkn0a8YNq3vOBVtkvNPilgqFpI/b88UDI/gU7Rcb8LSsVjKx+koP27vfBp0B9koD LD55Jq7iYblRHYgagwdibqGyFP+rZigFf6mgFrl6Ar+SPPntE4gAk+LYIBV2VuMOM/LI HDmjOmOq6aZg3VfT9O0w/tDNSVJetehECLvKpPWt8Jir7vMpwXJ0dPhny2rP5asiaTlX HwQA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:subject:to:cc:message-id:date:user-agent :mime-version:content-transfer-encoding; bh=FuVAJDlJKROQjGwF4tEeY7rvSS85Zas131f4yIJkyPM=; b=MzgS/jHv0nG0ZebpJlqhQ+nGaHdKXFc+5mAzBc8TuWNOo+qEubk1ndDQRB0wYR+eCM nP9fuX8RA/G51kreRo3BR8k0rc8enzHoT/yOFNFVed9gZ+ctW/1UvDKcLi9lrBYY2RlM MdYk1AWDsKRdUo7PLEut+2Zk5aVQ/mZQQnMwEVvPNWvqOVKXlA9R2tgHjnrLFbn5tm3t aKDLhav515sJKCCnSryL3KFpCnUWbMM8gLS/dLkaL2RnBMdLYaoObTY3uxAelWAchvuW sbtNbz7EyCukSdRoVQsMC4iof/MugSctRhjprQ+eMPZ1QaHLtlbiICZc0CrX+CTRh34y BVbQ== X-Gm-Message-State: AHYfb5ju/MNJJd2lPBeRlTTqHv/+C0yWeQMV4UCz6A47CodKpMeMWMO1 YZppG63O/BBVyA== X-Received: by 10.223.166.101 with SMTP id k92mr11677620wrc.283.1503380726101; Mon, 21 Aug 2017 22:45:26 -0700 (PDT) Received: from ?IPv6:2003:ea:8bc7:5e00:adff:5b3d:3003:445b? (p200300EA8BC75E00ADFF5B3D3003445B.dip0.t-ipconnect.de. [2003:ea:8bc7:5e00:adff:5b3d:3003:445b]) by smtp.googlemail.com with ESMTPSA id l5sm7787939wrg.93.2017.08.21.22.45.25 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 21 Aug 2017 22:45:25 -0700 (PDT) From: Heiner Kallweit Subject: [PATCH v2] i2c: core: add device-managed version of i2c_new_dummy To: Wolfram Sang Cc: "linux-i2c@vger.kernel.org" , Peter Rosin Message-ID: <8c0a982f-30d5-1124-c871-b040b5bce636@gmail.com> Date: Tue, 22 Aug 2017 07:45:18 +0200 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org i2c_new_dummy is typically called from the probe function of the driver for the primary i2c client. It requires calls to i2c_unregister_device in the error path of the probe function and in the remove function. This can be simplified by introducing a device-managed version. Note the changed error case return value type: i2c_new_dummy returns NULL whilst devm_new_i2c_dummy returns an ERR_PTR. Signed-off-by: Heiner Kallweit Reviewed-by: Peter Rosin --- v2: - added entry to Documentation/driver-model/devres.txt - extended documentation of new function - changed return value type to an ERR_PTR in case of error --- Documentation/driver-model/devres.txt | 3 +++ drivers/i2c/i2c-core-base.c | 39 +++++++++++++++++++++++++++++++++++ include/linux/i2c.h | 3 +++ 3 files changed, 45 insertions(+) diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt index 30e04f7a..67d59528 100644 --- a/Documentation/driver-model/devres.txt +++ b/Documentation/driver-model/devres.txt @@ -258,6 +258,9 @@ GPIO devm_gpio_request_one() devm_gpio_free() +I2C + devm_i2c_new_dummy + IIO devm_iio_device_alloc() devm_iio_device_free() diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 12822a4b..aac9491c 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -868,6 +868,45 @@ struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) } EXPORT_SYMBOL_GPL(i2c_new_dummy); +static void devm_i2c_release_dummy(struct device *dev, void *res) +{ + i2c_unregister_device(*(struct i2c_client **)res); +} + +/** + * devm_i2c_new_dummy - return a new i2c device bound to a dummy driver + * @dev: device the managed resource is bound to + * @adapter: the adapter managing the device + * @address: seven bit address to be used + * Context: can sleep + * + * This is the device-managed version of i2c_new_dummy. + * Note the changed return value type: It returns the new i2c client + * or an ERR_PTR in case of an error. + */ +struct i2c_client *devm_i2c_new_dummy(struct device *dev, + struct i2c_adapter *adapter, + u16 address) +{ + struct i2c_client *ret, **dr; + + dr = devres_alloc(devm_i2c_release_dummy, sizeof(*dr), GFP_KERNEL); + if (!dr) + return ERR_PTR(-ENOMEM); + + ret = i2c_new_dummy(adapter, address); + if (!ret) { + devres_free(dr); + return ERR_PTR(-EBUSY); + } + + *dr = ret; + devres_add(dev, dr); + + return ret; +} +EXPORT_SYMBOL_GPL(devm_i2c_new_dummy); + /** * i2c_new_secondary_device - Helper to get the instantiated secondary address * and create the associated device diff --git a/include/linux/i2c.h b/include/linux/i2c.h index d501d395..d0c091e6 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -381,6 +381,9 @@ extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr); extern struct i2c_client * i2c_new_dummy(struct i2c_adapter *adap, u16 address); +extern struct i2c_client * +devm_i2c_new_dummy(struct device *dev, struct i2c_adapter *adap, u16 address); + extern struct i2c_client * i2c_new_secondary_device(struct i2c_client *client, const char *name,