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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 E0B80C47255 for ; Mon, 11 May 2020 22:29:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AFB7A2070B for ; Mon, 11 May 2020 22:29:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=walle.cc header.i=@walle.cc header.b="YdDVOLeZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726173AbgEKW3x (ORCPT ); Mon, 11 May 2020 18:29:53 -0400 Received: from ssl.serverraum.org ([176.9.125.105]:38177 "EHLO ssl.serverraum.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725828AbgEKW3x (ORCPT ); Mon, 11 May 2020 18:29:53 -0400 Received: from ssl.serverraum.org (web.serverraum.org [172.16.0.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id E950223E4D; Tue, 12 May 2020 00:29:46 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1589236187; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZWtR9bzSYXnNm25amIJ9C/96FTsepP7H5IrzZ9zpG/A=; b=YdDVOLeZBQ34l+NCgbOJbibwaRMlbhkryBPCyVboFq3OoIIcwGhTb4bpx1oqBWsLm0T3Ny CZp5yyu0djrMsi4kOWfKCfNplFlS7gp1ntDK+bdoeton2uRftwbJISw7i+6IVo7b7aosbu kNxvxZ/YLMcP4rurnW92mHmhw4rdMek= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Tue, 12 May 2020 00:29:46 +0200 From: Michael Walle To: Rob Herring Cc: Andy Shevchenko , 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 , Jean Delvare , Guenter Roeck , Lee Jones , Thierry Reding , =?UTF-8?Q?Uwe_Kleine-K=C3=B6nig?= , Wim Van Sebroeck , Shawn Guo , Li Yang , Thomas Gleixner , Jason Cooper , Marc Zyngier , Mark Brown , Greg Kroah-Hartman Subject: Re: [PATCH v3 05/16] mfd: Add support for Kontron sl28cpld management controller In-Reply-To: References: <20200423174543.17161-1-michael@walle.cc> <20200423174543.17161-6-michael@walle.cc> <20200511211359.GB3518@bogus> User-Agent: Roundcube Webmail/1.4.4 Message-ID: <7acbb6d9b2240b1856136fa35c1318bf@walle.cc> X-Sender: michael@walle.cc Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org Am 2020-05-11 23:44, schrieb Michael Walle: > Am 2020-05-11 23:13, schrieb Rob Herring: >> On Thu, Apr 23, 2020 at 07:45:32PM +0200, Michael Walle wrote: >>> This patch adds core support for the board management controller >>> found >>> on the SMARC-sAL28 board. It consists of the following functions: >>> - watchdog >>> - GPIO controller >>> - PWM controller >>> - fan sensor >>> - interrupt controller >>> >>> At the moment, this controller is used on the Kontron SMARC-sAL28 >>> board. >>> >>> Please note that the MFD driver is defined as bool in the Kconfig >>> because the next patch will add interrupt support. >>> >>> Signed-off-by: Michael Walle >>> --- >>> drivers/mfd/Kconfig | 19 +++++ >>> drivers/mfd/Makefile | 2 + >>> drivers/mfd/sl28cpld.c | 153 >>> +++++++++++++++++++++++++++++++++++++++++ >>> 3 files changed, 174 insertions(+) >>> create mode 100644 drivers/mfd/sl28cpld.c >>> >>> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig >>> index 0a59249198d3..be0c8d93c526 100644 >>> --- a/drivers/mfd/Kconfig >>> +++ b/drivers/mfd/Kconfig >>> @@ -2060,5 +2060,24 @@ config SGI_MFD_IOC3 >>> If you have an SGI Origin, Octane, or a PCI IOC3 card, >>> then say Y. Otherwise say N. >>> >>> +config MFD_SL28CPLD >>> + bool "Kontron sl28 core driver" >>> + depends on I2C=y >>> + depends on OF >>> + select REGMAP_I2C >>> + select MFD_CORE >>> + help >>> + This option enables support for the board management controller >>> + found on the Kontron sl28 CPLD. You have to select individual >>> + functions, such as watchdog, GPIO, etc, under the corresponding >>> menus >>> + in order to enable them. >>> + >>> + Currently supported boards are: >>> + >>> + Kontron SMARC-sAL28 >>> + >>> + To compile this driver as a module, choose M here: the module >>> will be >>> + called sl28cpld. >>> + >>> endmenu >>> endif >>> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile >>> index f935d10cbf0f..9bc38863b9c7 100644 >>> --- a/drivers/mfd/Makefile >>> +++ b/drivers/mfd/Makefile >>> @@ -259,3 +259,5 @@ obj-$(CONFIG_MFD_ROHM_BD718XX) += rohm-bd718x7.o >>> obj-$(CONFIG_MFD_STMFX) += stmfx.o >>> >>> obj-$(CONFIG_SGI_MFD_IOC3) += ioc3.o >>> + >>> +obj-$(CONFIG_MFD_SL28CPLD) += sl28cpld.o >>> diff --git a/drivers/mfd/sl28cpld.c b/drivers/mfd/sl28cpld.c >>> new file mode 100644 >>> index 000000000000..1e5860cc7ffc >>> --- /dev/null >>> +++ b/drivers/mfd/sl28cpld.c >>> @@ -0,0 +1,153 @@ >>> +// SPDX-License-Identifier: GPL-2.0-only >>> +/* >>> + * MFD core for the sl28cpld. >>> + * >>> + * Copyright 2019 Kontron Europe GmbH >>> + */ >>> + >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> + >>> +#define SL28CPLD_VERSION 0x03 >>> +#define SL28CPLD_WATCHDOG_BASE 0x04 >>> +#define SL28CPLD_HWMON_FAN_BASE 0x0b >>> +#define SL28CPLD_PWM0_BASE 0x0c >>> +#define SL28CPLD_PWM1_BASE 0x0e >>> +#define SL28CPLD_GPIO0_BASE 0x10 >>> +#define SL28CPLD_GPIO1_BASE 0x15 >>> +#define SL28CPLD_GPO_BASE 0x1a >>> +#define SL28CPLD_GPI_BASE 0x1b >>> +#define SL28CPLD_INTC_BASE 0x1c >> >> If you want to use 'reg' in the binding, these are the numbers you >> should be using rather than making up numbering! > > My motivation is that I don't want to hardcode the internal addresses > of the management controller in the device tree. For example if they > will move around with a later update of the controller, so a driver can > be compatible with both the old and the new version. If they are in the > device tree, only one register layout is possible. > >> However, I still don't think you need any child nodes. All the data in >> the DT binding is right here in the driver already. There's no >> advantage >> to putting child nodes in DT, because this driver still has to be >> updated if you add more nodes. > > But then any phandle will reference the mfd device. And for example > there > are two different interrupt controllers, that is the INTC and the > GPIO[01], > which will then be combined into one device tree node, right? > > So the mfd node would be > > cpld: sl28cpld@4a { > interrupt-controller; > #interrupt-cells = <2>; > gpio-controller; > #gpio-cells = <2>; > [..] > }; > > and then depending on the mapping one could use: > > interrupts-extended = <&cpld 0 FLAGS>; /* gpio0 line 0 */ > interrupts-extended = <&cpld 8 FLAGS>; /* gpio1 line 0 */ > interrupts-extended = <&cpld 12 FLAGS>; /* irq0 */ > > gpios = <&cpld 0> /* gpio0 line 0 */ > > But there is also offset 12, but then it is the GPI controller: > > gpios = <&cpld 12> /* gpi line 0, nothing to do with irq0 */ > > I don't know if this is good practice, I guess you have to tell me. And > is it possible to combine any sub device into the mfd node in that way? Oh I don't think that will work for the watchdog. If you just have one watchdog it just looks odd. cpld: sl28cpld@4a { interrupt-controller; #interrupt-cells = <2>; gpio-controller; #gpio-cells = <2>; timeout-sec = <10>; /* watchdog property */ }; And won't pass the dtbindings check because the nodename is not "watchdog(@[0-9]+)?". But it really falls short if you want to have two watchdogs with different properties. -michael