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=-8.3 required=3.0 tests=BAYES_00, BODY_QUOTE_MALF_MSGID,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 901D4C43462 for ; Tue, 28 Jul 2020 07:19:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 63C5C207E8 for ; Tue, 28 Jul 2020 07:19:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="JXEuNNcH" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727970AbgG1HTz (ORCPT ); Tue, 28 Jul 2020 03:19:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53818 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727957AbgG1HTy (ORCPT ); Tue, 28 Jul 2020 03:19:54 -0400 Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7139BC061794 for ; Tue, 28 Jul 2020 00:19:53 -0700 (PDT) Received: by mail-wr1-x442.google.com with SMTP id r2so12116358wrs.8 for ; Tue, 28 Jul 2020 00:19:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=A6d3Z8kZUGC925O1zWNYM0bo3uk23MCvzFLEsbquiGg=; b=JXEuNNcHl2rzr+ED0k+nl9svIqEnZlG4uG4Ljc30XUWAj7SnsAlzcGFXU0TA0qySQp 2hN8vHtrdyO41dqHRHbNgoPQzccQFeCCY6lxquSVVAhovTXq6dPgHYkQUkx8svw4D+R0 S4BMdFPVl/rUzIVO23T1URDRTzQGmFn9sx0zrNCH204f4ED8wjuqjvMVBZi6Ppsks+19 hQ7s7EkaKV6A5zuNCyrLunYI0x5kEFw4WpSbXhjth3EzCbft0KrRwaTWixEGNYRb6VuB tNNZE8QWXi5j313UCjrpXPViIvmQh52nbvxLtzHyVIeCG53hZNdFNx7NVcKvUdxb0ZLk 0Vug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=A6d3Z8kZUGC925O1zWNYM0bo3uk23MCvzFLEsbquiGg=; b=e5E5KrIgoJhwvRlv3hTntRn//gLs5496C+TL5uvJJBWboOtFl2ePiRj//EOB43cJgK EQO/eyZ3JMeMZbWmwj2WvmUUjJe8YdteMLMqX89+uAu02kedZWnS25CAOdOr0A5G7swc MEYXQIOPdlIQew5JRkOxBdqFgxUXhRueHHI9lnZ7w/xOjFXPilrBan++OCPrj1X+MkS3 HqQ8O85dDj8zujue19fb74nOY5Uz9l/4JnKHEKjhTzILbsZM4YIM59j+aJfdlSl3zMjV n2n8vM3OOHcL9w86S9LcmM0+4mJhfMNA+HTK6dr2C1+wVO1LMWHSF9r4r6iDzVvYFxBa uZqg== X-Gm-Message-State: AOAM5309Z38XGm+y62Kdj42qkRfizlrAfJdEeP5zL7osZrawXmLy8S0y Db1NsqQHyu3fFoK1M7CqtOlp8w== X-Google-Smtp-Source: ABdhPJz+8EDiCF+tZuc+BFokpxg7sLtYNmRW3CW3BfMrYAARno5y9fdOlWpYou7Mu+g++TZQFZ/NPw== X-Received: by 2002:adf:f289:: with SMTP id k9mr24097714wro.203.1595920792029; Tue, 28 Jul 2020 00:19:52 -0700 (PDT) Received: from dell ([2.27.167.73]) by smtp.gmail.com with ESMTPSA id j11sm15809923wrq.69.2020.07.28.00.19.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 28 Jul 2020 00:19:51 -0700 (PDT) Date: Tue, 28 Jul 2020 08:19:49 +0100 From: Lee Jones To: Michael Walle Cc: linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-pwm@vger.kernel.org, linux-watchdog@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Linus Walleij , Bartosz Golaszewski , Rob Herring , Jean Delvare , Guenter Roeck , Thierry Reding , Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= , Wim Van Sebroeck , Shawn Guo , Li Yang , Thomas Gleixner , Jason Cooper , Marc Zyngier , Mark Brown , Greg Kroah-Hartman , Andy Shevchenko , Catalin Marinas , Will Deacon , Pavel Machek Subject: Re: [PATCH v6 01/13] mfd: add simple regmap based I2C driver Message-ID: <20200728071949.GE1850026@dell> References: <20200725231834.25642-1-michael@walle.cc> <20200725231834.25642-2-michael@walle.cc> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200725231834.25642-2-michael@walle.cc> Sender: linux-watchdog-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org On Sun, 26 Jul 2020, Michael Walle wrote: > There are I2C devices which contain several different functions but > doesn't require any special access functions. For these kind of drivers > an I2C regmap should be enough. > > Create an I2C driver which creates an I2C regmap and enumerates its > children. If a device wants to use this as its MFD core driver, it has > to add an individual compatible string. It may provide its own regmap > configuration. > > Subdevices can use dev_get_regmap() on the parent to get their regmap > instance. > > Signed-off-by: Michael Walle > --- > Changes since v5: > - removed "select MFD_CORE" in Kconfig > - removed help text in Kconfig, we assume that the users of this That's the opposite of what I asked for. > driver will have a "select MFD_SIMPLE_MFD_I2C". Instead added > a small description to the driver itself. > - removed "struct simple_mfd_i2c_config" and use regmap_config > directly > - changed builtin_i2c_driver() to module_i2c_driver(), added > MODULE_ boilerplate > - cleaned up the included files > > Changes since v4: > - new patch. Lee, please bear with me. I didn't want to delay the > new version (where a lot of remarks on the other patches were > addressed) even more, just because we haven't figured out how > to deal with the MFD part. So for now, I've included this one. > > drivers/mfd/Kconfig | 5 ++++ > drivers/mfd/Makefile | 1 + > drivers/mfd/simple-mfd-i2c.c | 55 ++++++++++++++++++++++++++++++++++++ > 3 files changed, 61 insertions(+) > create mode 100644 drivers/mfd/simple-mfd-i2c.c > > diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig > index 33df0837ab41..c08539c7a166 100644 > --- a/drivers/mfd/Kconfig > +++ b/drivers/mfd/Kconfig > @@ -1162,6 +1162,11 @@ config MFD_SI476X_CORE > To compile this driver as a module, choose M here: the > module will be called si476x-core. > > +config MFD_SIMPLE_MFD_I2C > + tristate > + depends on I2C > + select REGMAP_I2C Please provide a full help. > config MFD_SM501 > tristate "Silicon Motion SM501" > depends on HAS_DMA > diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile > index a60e5f835283..78d24a3e7c9e 100644 > --- a/drivers/mfd/Makefile > +++ b/drivers/mfd/Makefile > @@ -264,3 +264,4 @@ obj-$(CONFIG_MFD_STMFX) += stmfx.o > obj-$(CONFIG_MFD_KHADAS_MCU) += khadas-mcu.o > > obj-$(CONFIG_SGI_MFD_IOC3) += ioc3.o > +obj-$(CONFIG_MFD_SIMPLE_MFD_I2C) += simple-mfd-i2c.o > diff --git a/drivers/mfd/simple-mfd-i2c.c b/drivers/mfd/simple-mfd-i2c.c > new file mode 100644 > index 000000000000..45090ddad104 > --- /dev/null > +++ b/drivers/mfd/simple-mfd-i2c.c > @@ -0,0 +1,55 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * A very simple I2C MFD driver Simple MFD - I2C > + * The driver enumerates its children and registers a common regmap. Use > + * dev_get_regmap(pdev->dev.parent, NULL) in the child nodes to fetch that > + * regmap instance. This driver creates a single register map with the intention for it to be shared by all sub-devices. Children can use their parent's device structure (dev.parent) in order reference it. > + * In the future this driver might be extended to support also other interfaces > + * like SPI etc. Remove this please. > + */ '\n' here. > +#include > +#include > +#include > +#include > +#include > + > +static const struct regmap_config simple_regmap_config = { > + .reg_bits = 8, > + .val_bits = 8, > +}; > + > +static int simple_mfd_i2c_probe(struct i2c_client *i2c) > +{ > + const struct regmap_config *config; > + struct regmap *regmap; > + > + config = device_get_match_data(&i2c->dev); > + if (!config) > + config = &simple_regmap_config; > + > + regmap = devm_regmap_init_i2c(i2c, config); > + if (IS_ERR(regmap)) > + return PTR_ERR(regmap); > + > + return devm_of_platform_populate(&i2c->dev); > +} > + > +static const struct of_device_id simple_mfd_i2c_of_match[] = { > + {} > +}; > +MODULE_DEVICE_TABLE(of, simple_mfd_i2c_of_match); > + > +static struct i2c_driver simple_mfd_i2c_driver = { > + .probe_new = simple_mfd_i2c_probe, > + .driver = { > + .name = "simple-mfd-i2c", > + .of_match_table = simple_mfd_i2c_of_match, > + }, > +}; > +module_i2c_driver(simple_mfd_i2c_driver); > + > +MODULE_AUTHOR("Michael Walle "); > +MODULE_DESCRIPTION("Simple I2C MFD driver"); Simple MFD - I2C driver > +MODULE_LICENSE("GPL v2"); -- Lee Jones [李琼斯] Senior Technical Lead - Developer Services Linaro.org │ Open source software for Arm SoCs Follow Linaro: Facebook | Twitter | Blog