From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751004AbdALQu7 (ORCPT ); Thu, 12 Jan 2017 11:50:59 -0500 Received: from hqemgate14.nvidia.com ([216.228.121.143]:14453 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750733AbdALQu5 (ORCPT ); Thu, 12 Jan 2017 11:50:57 -0500 X-PGP-Universal: processed; by hqnvupgp07.nvidia.com on Wed, 11 Jan 2017 20:46:48 -0800 Message-ID: <5877B088.5040007@nvidia.com> Date: Thu, 12 Jan 2017 22:06:24 +0530 From: Laxman Dewangan User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Thierry Reding , Sebastian Reichel CC: Martin Michlmayr , , , Chaitanya Bandi Subject: Re: [PATCH] power: reset: Add MAX77620 support References: <20170112161507.23774-1-thierry.reding@gmail.com> In-Reply-To: <20170112161507.23774-1-thierry.reding@gmail.com> X-Originating-IP: [10.19.65.30] X-ClientProxiedBy: DRUKMAIL101.nvidia.com (10.25.59.19) To bgmail102.nvidia.com (10.25.59.11) Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 12 January 2017 09:45 PM, Thierry Reding wrote: > From: Thierry Reding > > The Maxim MAX77620 PMIC has the ability to power off and restart the > system. Add a driver that supports power off (via pm_power_off()) and > restart (via arm_pm_restart() on 32-bit and 64-bit ARM). > > Based on work by Chaitanya Bandi . > > Cc: Chaitanya Bandi > Signed-off-by: Thierry Reding > --- > drivers/power/reset/Kconfig | 6 ++ > drivers/power/reset/Makefile | 1 + > drivers/power/reset/max77620-poweroff.c | 146 ++++++++++++++++++++++++++++++++ > 3 files changed, 153 insertions(+) > create mode 100644 drivers/power/reset/max77620-poweroff.c > > diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig > index abeb77217a21..f0d0c20632f8 100644 > --- a/drivers/power/reset/Kconfig > +++ b/drivers/power/reset/Kconfig > @@ -98,6 +98,12 @@ config POWER_RESET_IMX > say N here or disable in dts to make sure pm_power_off never be > overwrote wrongly by this driver. > > +config POWER_RESET_MAX77620 > + bool "Maxim MAX77620 PMIC power-off driver" > + depends on MFD_MAX77620 > + help > + Power off and restart support for Maxim MAX77620 PMICs. > + > config POWER_RESET_MSM > bool "Qualcomm MSM power-off driver" > depends on ARCH_QCOM > diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile > index 11dae3b56ff9..74511d2f037a 100644 > --- a/drivers/power/reset/Makefile > +++ b/drivers/power/reset/Makefile > @@ -9,6 +9,7 @@ obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o > obj-$(CONFIG_POWER_RESET_GPIO_RESTART) += gpio-restart.o > obj-$(CONFIG_POWER_RESET_HISI) += hisi-reboot.o > obj-$(CONFIG_POWER_RESET_IMX) += imx-snvs-poweroff.o > +obj-$(CONFIG_POWER_RESET_MAX77620) += max77620-poweroff.o > obj-$(CONFIG_POWER_RESET_MSM) += msm-poweroff.o > obj-$(CONFIG_POWER_RESET_PIIX4_POWEROFF) += piix4-poweroff.o > obj-$(CONFIG_POWER_RESET_LTC2952) += ltc2952-poweroff.o > diff --git a/drivers/power/reset/max77620-poweroff.c b/drivers/power/reset/max77620-poweroff.c > new file mode 100644 > index 000000000000..4f2682d10925 > --- /dev/null > +++ b/drivers/power/reset/max77620-poweroff.c > @@ -0,0 +1,146 @@ > +/* > + * Power off driver for Maxim MAX77620 device. > + * > + * Copyright (c) 2014-2016, NVIDIA CORPORATION. All rights reserved. Should we change year here? > + * > + * Based on work by Chaitanya Bandi . > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License as > + * published by the Free Software Foundation version 2. > + * > + * This program is distributed "as is" WITHOUT ANY WARRANTY of any kind, > + * whether express or implied; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + * General Public License for more details. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) > +#include > +#endif > + > +struct max77620_power { > + struct regmap *regmap; > + struct device *dev; > +}; > + > +static struct max77620_power *system_power_controller = NULL; As this is static and so already initialized as NULL. Hence we may not need to explicitly NULL initialization. > + > +static void max77620_pm_power_off(void) > +{ > + struct max77620_power *power = system_power_controller; > + unsigned int value; > + int err; > + > + if (!power) > + return; > + > + /* clear power key interrupts */ > + err = regmap_read(power->regmap, MAX77620_REG_ONOFFIRQ, &value); > + if (err < 0) > + dev_err(power->dev, "failed to clear power key interrupts: %d\n", err); > + > + /* clear RTC interrupts */ > + /* > + err = regmap_read(power->regmap, MAX77620_REG_RTCINT, &value); > + if (err < 0) > + dev_err(power->dev, "failed to clear RTC interrupts: %d\n", err); > + */ > + > + /* clear TOP interrupts */ > + err = regmap_read(power->regmap, MAX77620_REG_IRQTOP, &value); > + if (err < 0) > + dev_err(power->dev, "failed to clear interrupts: %d\n", err); > + > + err = regmap_update_bits(power->regmap, MAX77620_REG_ONOFFCNFG2, > + MAX77620_ONOFFCNFG2_SFT_RST_WK, 0); > + if (err < 0) > + dev_err(power->dev, "failed to clear SFT_RST_WK: %d\n", err); > + > + err = regmap_update_bits(power->regmap, MAX77620_REG_ONOFFCNFG1, > + MAX77620_ONOFFCNFG1_SFT_RST, > + MAX77620_ONOFFCNFG1_SFT_RST); > + if (err < 0) > + dev_err(power->dev, "failed to set SFT_RST: %d\n", err); > +} > + > +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) > +static void max77620_pm_restart(enum reboot_mode mode, const char *cmd) > +{ > + struct max77620_power *power = system_power_controller; > + int err; > + > + if (!power) > + return; > + > + err = regmap_update_bits(power->regmap, MAX77620_REG_ONOFFCNFG2, > + MAX77620_ONOFFCNFG2_SFT_RST_WK, > + MAX77620_ONOFFCNFG2_SFT_RST_WK); > + if (err < 0) > + dev_err(power->dev, "failed to set SFT_RST_WK: %d\n", err); > + > + err = regmap_update_bits(power->regmap, MAX77620_REG_ONOFFCNFG1, > + MAX77620_ONOFFCNFG1_SFT_RST, > + MAX77620_ONOFFCNFG1_SFT_RST); > + if (err < 0) > + dev_err(power->dev, "failed to set SFT_RST: %d\n", err); > +} > +#endif > + > +static int max77620_poweroff_probe(struct platform_device *pdev) > +{ > + struct max77620_chip *max77620 = dev_get_drvdata(pdev->dev.parent); > + struct device_node *np = pdev->dev.parent->of_node; > + struct max77620_power *power; > + unsigned int value; > + int err; > + > + if (!of_property_read_bool(np, "system-power-controller")) > + return 0; > + > + power = devm_kzalloc(&pdev->dev, sizeof(*power), GFP_KERNEL); > + if (!power) > + return -ENOMEM; > + > + power->regmap = max77620->rmap; We can use the function info->regmap = dev_get_regmap(parent, NULL); to get the regmap. This will make this driver independent of max77620 chip and extend same for other Maxim Chips. > + power->dev = &pdev->dev; > + > + err = regmap_read(power->regmap, MAX77620_REG_NVERC, &value); > + if (err < 0) { > + dev_err(power->dev, "failed to read event recorder: %d\n", err); > + return err; > + } > + > + dev_dbg(&pdev->dev, "event recorder: %#x\n", value); > + > + system_power_controller = power; > + pm_power_off = max77620_pm_power_off; > +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) > + arm_pm_restart = max77620_pm_restart; What if we want to reset via the Tegra and not through PMIC? > +#endif > + > + return 0; > +} > + > +static struct platform_driver max77620_poweroff_driver = { > + .driver = { > + .name = "max77620-power", > + }, > + .probe = max77620_poweroff_probe, > +}; > +module_platform_driver(max77620_poweroff_driver); > + > +MODULE_DESCRIPTION("Maxim MAX77620 PMIC power off and restart driver"); > +MODULE_AUTHOR("Thierry Reding "); > +MODULE_ALIAS("platform:max77620-power"); > +MODULE_LICENSE("GPL v2");