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=-17.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 DC3CBC47423 for ; Thu, 24 Sep 2020 19:26:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 88639221EB for ; Thu, 24 Sep 2020 19:26:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="PauaGvg+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728842AbgIXT0t (ORCPT ); Thu, 24 Sep 2020 15:26:49 -0400 Received: from mout.gmx.net ([212.227.15.15]:56357 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728733AbgIXT0r (ORCPT ); Thu, 24 Sep 2020 15:26:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1600975568; bh=ryafog9o9EYAigK/QILvakc48q9JWXrf1x8ta4Cd9NE=; h=X-UI-Sender-Class:From:To:Cc:Subject:Date:In-Reply-To:References; b=PauaGvg+ZaP1l1iygBOq/z2lbo9A0OPi/4BEctJPRszoVsS0vUdIYUEcMQx8ui00m wYtVF61MaEf568sVa3DFahuDTOazR9EuRz4W0Lie3TpfC1NkM5QoTaJTuoHm0gUoGj BuTPJT3tkRGFmzGutTVjCpuO3dmNxbTYk7tHioec= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from longitude ([5.146.195.151]) by mail.gmx.com (mrgmx005 [212.227.17.190]) with ESMTPSA (Nemesis) id 1MWASe-1jxlbh3XT8-00XesV; Thu, 24 Sep 2020 21:26:08 +0200 From: =?UTF-8?q?Jonathan=20Neusch=C3=A4fer?= To: linux-kernel@vger.kernel.org Cc: Lee Jones , Rob Herring , =?UTF-8?q?Jonathan=20Neusch=C3=A4fer?= , Thierry Reding , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Alessandro Zummo , Alexandre Belloni , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , Sam Ravnborg , Linus Walleij , Heiko Stuebner , Stephan Gerhold , Lubomir Rintel , Mark Brown , allen , Mauro Carvalho Chehab , "David S. Miller" , devicetree@vger.kernel.org, linux-pwm@vger.kernel.org, linux-rtc@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Heiko Stuebner , Josua Mayer , Andreas Kemnade , Arnd Bergmann , Daniel Palmer , Andy Shevchenko Subject: [PATCH v3 3/7] mfd: Add base driver for Netronix embedded controller Date: Thu, 24 Sep 2020 21:24:51 +0200 Message-Id: <20200924192455.2484005-4-j.neuschaefer@gmx.net> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200924192455.2484005-1-j.neuschaefer@gmx.net> References: <20200924192455.2484005-1-j.neuschaefer@gmx.net> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:2/sqEliv+PQ0uN2Fo4ra2eRrVTl8o/Sf3HWGB8zZ60Z2X3NTHQt yeDk+anplblmj7G5BB89xLmR9C23HI+mIvNDa/OcdMixx+J3Nc/Oy4Biyy16X3CGA4cAB5H hOePproobbVdyIU8zIyp7QtCD2K08q9+4urGmp5tvD3jPZiEWkQu0ACNogFsYyyQRpJzp8Q odoOATePEkLWDVa8xZffA== X-UI-Out-Filterresults: notjunk:1;V03:K0:j69ta80NZrE=:Ny0rWmCQF7G6B5zUJgwpVi h6QNlCb29XBEpAIQl78KC0fKYDD9KlPCf8hwu8ibI4H8CUf7oyWVv90dVJ1xFuUcAkUjPxyAS 7SyxtreYjV2fVyfS2lAt+WyDvXBm5opYVaT2L07c/ePbJfVlv4o1aBHpgKeEIj8I24UHMLo9n cX51XmeyFrCFNpnPk5JuqBr7QkyHX/hB6eU+UWqhwfgcMjfNnpZuAW+Bq4ACbEmkYbOwtcjJB 2W1mlOyQGtPG1Ns2dXK6XSgqxQpVaWSauHgLh7wk9+Ik7F7/XtV7jsD2UgFnUxKuuh+IMxRVU hgk6fp+1nYLWQqq0MinPhsNPgkknwLs4UXoewabFyWcE/0Lg9NeDiJ4jGXuUbnl5sV8e9HYzc Qyu0S2Q3D/IdM23tttQFp1UqHEObzQUsCf3IUuODpR8BDtJZmrnCaTJ4vswl/MqICBeYRozZa ObXS6sNRmVSjQV0M4a8qKfecaIvrsJOVqxKceMJNuPTeslnudm14sULt1DfQfJ9r1esTTlfic o19jOL97uwdsY4SFisDE3fjA8CvTRBwXpCKO9J4cQ8pvFiDZaS1oMtqWsHlkFH1UhhtoCfCI2 +yHoPyrOdwTEwyQ9qhx7tIFyqhZ6tx0zzwUCFOdVMhus5yaLydxCf5s94GuX9ddez2GTH2IhH OPjmkGjoblzXwCVmQZ7XjB85pMy5/4cNQJ9kh5NZF2LgNMPCxI5+8wV9ea5p1Y1CaOlhokqAx OFs/YOGZDImRsbQ0xO19I7C66Pm7wf/duyCqA623URiUEzusZWNGdgtLHiBcGQcwHh9xlLZwb KmeW8PkFV8ZkCExo+J05A59PBFwFTe5+V6eMs+f445yGH8cMt3tQgIKBlI4xk/vsWXZ1DTHCC v0XF6cdMOl8kR/E4UoK3Cck0hZY0SdaPU1pgxoPEe/p0r3t7m1bVPfEdSwCPVH5swBfMLjBac AelFL+tKx7C93v9oFexE5YJWclECKpjXB3cmYDHG8qIUo/wQCyNGfW0z+jk5QcN7V/BHHGaTy dckX5wQ6LtcwJaRxm99O+K8kWQiMeyjh4U0ukwXbpTBUYFnlDIbNpLFreY675M8iv6UTp05mv +JS9Hiu8ggOhMz/SlWK9FdHp/ot7Bp4TlFyWDcUBs88yBMkZ5BOGS0ShWRkXaockHIzyf8uSz s59Gj3wms6ICmss15zjbGiFNDvhEyLWmDf/MmTGuWGXWHhHtwDEdYUpQu49n8Jl1yRZapOI0l lpDhAABKu8rKfQqkr5uV7BSlozaBlTTIBKCS9Yg== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The Netronix embedded controller is a microcontroller found in some e-book readers designed by the ODM Netronix, Inc. It contains RTC, battery monitoring, system power management, and PWM functionality. This driver implements register access and version detection. Third-party hardware documentation is available at: https://github.com/neuschaefer/linux/wiki/Netronix-MSP430-embedded-contr= oller The EC supports interrupts, but the driver doesn't make use of them so far. Signed-off-by: Jonathan Neusch=C3=A4fer =2D-- v3: - Add (EC) to CONFIG_MFD_NTXEC prompt - Relicense as GPLv2 or later - Add email address to copyright line - remove empty lines in ntxec_poweroff and ntxec_restart functions - Split long lines - Remove 'Install ... handler' comments - Make naming of struct i2c_client parameter consistent - Remove struct ntxec_info - Rework 'depends on' lines in Kconfig, hard-depend on I2C, select REGMAP_= I2C and MFD_CORE - Register subdevices via mfd_cells - Move 8-bit register conversion to ntxec.h v2: - https://lore.kernel.org/lkml/20200905133230.1014581-4-j.neuschaefer@gmx.= net/ - Add a description of the device to the patch text - Unify spelling as 'Netronix embedded controller'. 'Netronix' is the proper name of the manufacturer, but 'embedded control= ler' is just a label that I have assigned to the device. - Switch to regmap, avoid regmap use in poweroff and reboot handlers. Inspired by cf84dc0bb40f4 ("mfd: rn5t618: Make restart handler atomic sa= fe") - Use a list of known-working firmware versions instead of checking for a known-incompatible version - Prefix registers with NTXEC_REG_ - Define register values as constants - Various style cleanups as suggested by Lee Jones - Don't align =3D signs in struct initializers [Uwe Kleine-K=C3=B6nig] - Don't use dev_dbg for an error message - Explain sleep in poweroff handler - Remove (struct ntxec).client - Switch to .probe_new in i2c driver - Add .remove callback - Make CONFIG_MFD_NTXEC a tristate option =2D-- drivers/mfd/Kconfig | 10 ++ drivers/mfd/Makefile | 1 + drivers/mfd/ntxec.c | 206 ++++++++++++++++++++++++++++++++++++++ include/linux/mfd/ntxec.h | 31 ++++++ 4 files changed, 248 insertions(+) create mode 100644 drivers/mfd/ntxec.c create mode 100644 include/linux/mfd/ntxec.h diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig index 33df0837ab415..b313103151508 100644 =2D-- a/drivers/mfd/Kconfig +++ b/drivers/mfd/Kconfig @@ -978,6 +978,16 @@ config MFD_VIPERBOARD You need to select the mfd cell drivers separately. The drivers do not support all features the board exposes. +config MFD_NTXEC + tristate "Netronix embedded controller (EC)" + depends on OF || COMPILE_TEST + depends on I2C + select REGMAP_I2C + select MFD_CORE + help + Say yes here if you want to support the embedded controller found in + certain e-book readers designed by the ODM Netronix. + config MFD_RETU tristate "Nokia Retu and Tahvo multi-function device" select MFD_CORE diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile index a60e5f835283e..236a8acd917a0 100644 =2D-- a/drivers/mfd/Makefile +++ b/drivers/mfd/Makefile @@ -217,6 +217,7 @@ obj-$(CONFIG_MFD_INTEL_MSIC) +=3D intel_msic.o obj-$(CONFIG_MFD_INTEL_PMC_BXT) +=3D intel_pmc_bxt.o obj-$(CONFIG_MFD_PALMAS) +=3D palmas.o obj-$(CONFIG_MFD_VIPERBOARD) +=3D viperboard.o +obj-$(CONFIG_MFD_NTXEC) +=3D ntxec.o obj-$(CONFIG_MFD_RC5T583) +=3D rc5t583.o rc5t583-irq.o obj-$(CONFIG_MFD_RK808) +=3D rk808.o obj-$(CONFIG_MFD_RN5T618) +=3D rn5t618.o diff --git a/drivers/mfd/ntxec.c b/drivers/mfd/ntxec.c new file mode 100644 index 0000000000000..93611b85a32e0 =2D-- /dev/null +++ b/drivers/mfd/ntxec.c @@ -0,0 +1,206 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * The Netronix embedded controller is a microcontroller found in some + * e-book readers designed by the ODM Netronix, Inc. It contains RTC, + * battery monitoring, system power management, and PWM functionality. + * + * This driver implements register access, version detection, and system + * power-off/reset. + * + * Copyright 2020 Jonathan Neusch=C3=A4fer + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define NTXEC_REG_VERSION 0x00 +#define NTXEC_REG_POWEROFF 0x50 +#define NTXEC_REG_POWERKEEP 0x70 +#define NTXEC_REG_RESET 0x90 + +#define NTXEC_POWEROFF_VALUE 0x0100 +#define NTXEC_POWERKEEP_VALUE 0x0800 +#define NTXEC_RESET_VALUE 0xff00 + +static struct i2c_client *poweroff_restart_client; + +static void ntxec_poweroff(void) +{ + int res; + u8 buf[] =3D { + NTXEC_REG_POWEROFF, + (NTXEC_POWEROFF_VALUE >> 8) & 0xff, + NTXEC_POWEROFF_VALUE & 0xff, + }; + struct i2c_msg msgs[] =3D { + { + .addr =3D poweroff_restart_client->addr, + .flags =3D 0, + .len =3D sizeof(buf), + .buf =3D buf + } + }; + + res =3D i2c_transfer(poweroff_restart_client->adapter, msgs, ARRAY_SIZE(= msgs)); + if (res < 0) + dev_alert(&poweroff_restart_client->dev, + "Failed to power off (err =3D %d)\n", res); + + /* + * The time from the register write until the host CPU is powered off + * has been observed to be about 2.5 to 3 seconds. Sleep long enough to + * safely avoid returning from the poweroff handler. + */ + msleep(5000); +} + +static int ntxec_restart(struct notifier_block *nb, + unsigned long action, void *data) +{ + int res; + /* + * NOTE: The lower half of the reset value is not sent, because sending + * it causes an error + */ + u8 buf[] =3D { + NTXEC_REG_RESET, + (NTXEC_RESET_VALUE >> 8) & 0xff, + }; + struct i2c_msg msgs[] =3D { + { + .addr =3D poweroff_restart_client->addr, + .flags =3D 0, + .len =3D sizeof(buf), + .buf =3D buf + } + }; + + res =3D i2c_transfer(poweroff_restart_client->adapter, msgs, ARRAY_SIZE(= msgs)); + if (res < 0) + dev_alert(&poweroff_restart_client->dev, + "Failed to restart (err =3D %d)\n", res); + + return NOTIFY_DONE; +} + +static struct notifier_block ntxec_restart_handler =3D { + .notifier_call =3D ntxec_restart, + .priority =3D 128 +}; + +static const struct regmap_config regmap_config =3D { + .name =3D "ntxec", + .reg_bits =3D 8, + .val_bits =3D 16, + .cache_type =3D REGCACHE_NONE, + .val_format_endian =3D REGMAP_ENDIAN_BIG, +}; + +static const struct mfd_cell ntxec_subdevices[] =3D { + { .name =3D "ntxec-rtc" }, + { .name =3D "ntxec-pwm" }, +}; + +static int ntxec_probe(struct i2c_client *client) +{ + struct ntxec *ec; + unsigned int version; + int res; + + ec =3D devm_kmalloc(&client->dev, sizeof(*ec), GFP_KERNEL); + if (!ec) + return -ENOMEM; + + ec->dev =3D &client->dev; + + ec->regmap =3D devm_regmap_init_i2c(client, ®map_config); + if (IS_ERR(ec->regmap)) { + dev_err(ec->dev, "Failed to set up regmap for device\n"); + return res; + } + + /* Determine the firmware version */ + res =3D regmap_read(ec->regmap, NTXEC_REG_VERSION, &version); + if (res < 0) { + dev_err(ec->dev, "Failed to read firmware version number\n"); + return res; + } + dev_info(ec->dev, + "Netronix embedded controller version %04x detected.\n", + version); + + /* Bail out if we encounter an unknown firmware version */ + switch (version) { + case 0xd726: /* found in Kobo Aura */ + break; + default: + return -ENODEV; + } + + if (of_device_is_system_power_controller(ec->dev->of_node)) { + /* + * Set the 'powerkeep' bit. This is necessary on some boards + * in order to keep the system running. + */ + res =3D regmap_write(ec->regmap, NTXEC_REG_POWERKEEP, + NTXEC_POWERKEEP_VALUE); + if (res < 0) + return res; + + WARN_ON(poweroff_restart_client); + poweroff_restart_client =3D client; + if (pm_power_off) + dev_err(ec->dev, "pm_power_off already assigned\n"); + else + pm_power_off =3D ntxec_poweroff; + + res =3D register_restart_handler(&ntxec_restart_handler); + if (res) + dev_err(ec->dev, + "Failed to register restart handler: %d\n", res); + } + + i2c_set_clientdata(client, ec); + + res =3D devm_mfd_add_devices(ec->dev, PLATFORM_DEVID_NONE, ntxec_subdevi= ces, + ARRAY_SIZE(ntxec_subdevices), NULL, 0, NULL); + if (res) + dev_warn(ec->dev, "Failed to add subdevices: %d\n", res); + + return res; +} + +static int ntxec_remove(struct i2c_client *client) +{ + if (client =3D=3D poweroff_restart_client) { + poweroff_restart_client =3D NULL; + pm_power_off =3D NULL; + unregister_restart_handler(&ntxec_restart_handler); + } + + return 0; +} + +static const struct of_device_id of_ntxec_match_table[] =3D { + { .compatible =3D "netronix,ntxec", }, + {} +}; + +static struct i2c_driver ntxec_driver =3D { + .driver =3D { + .name =3D "ntxec", + .of_match_table =3D of_ntxec_match_table, + }, + .probe_new =3D ntxec_probe, + .remove =3D ntxec_remove, +}; +module_i2c_driver(ntxec_driver); diff --git a/include/linux/mfd/ntxec.h b/include/linux/mfd/ntxec.h new file mode 100644 index 0000000000000..a39c85978f61b =2D-- /dev/null +++ b/include/linux/mfd/ntxec.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright 2020 Jonathan Neusch=C3=A4fer + * + * Register access and version information for the Netronix embedded + * controller. + */ + +#ifndef NTXEC_H +#define NTXEC_H + +#include + +struct ntxec { + struct device *dev; + struct regmap *regmap; +}; + +/* + * Some registers, such as the battery status register (0x41), are in + * big-endian, but others only have eight significant bits, which are in = the + * first byte transmitted over I2C (the MSB of the big-endian value). + * This convenience function converts an 8-bit value to 16-bit for use in= the + * second kind of register. + */ +static inline u16 ntxec_reg8(u8 value) +{ + return value << 8; +} + +#endif =2D- 2.28.0