Messages in this thread | | | Date | Fri, 13 Jan 2017 04:44:25 +0100 | From | Sebastian Reichel <> | Subject | Re: [PATCH] power: reset: Add MAX77620 support |
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Hi Thierry,
I have a few comments inline.
On Thu, Jan 12, 2017 at 05:15:07PM +0100, Thierry Reding wrote: > 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 <bandik@nvidia.com>. > > Cc: Chaitanya Bandi <bandik@nvidia.com> > Signed-off-by: Thierry Reding <treding@nvidia.com> > --- > 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. > + * > + * Based on work by Chaitanya Bandi <bandik@nvidia.com>. > + * > + * 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 <linux/errno.h> > +#include <linux/mfd/max77620.h> > +#include <linux/module.h> > +#include <linux/notifier.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/reboot.h> > +#include <linux/regmap.h> > +#include <linux/slab.h> > + > +#if defined(CONFIG_ARM) || defined(CONFIG_ARM64) > +#include <asm/system_misc.h> > +#endif > + > +struct max77620_power { > + struct regmap *regmap; > + struct device *dev; > +}; > + > +static struct max77620_power *system_power_controller = NULL; > + > +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 (system_power_controller) return -EINVAL;
> + 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; > + 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; > +#endif
Please use register_restart_handler() instead. It has support for priorities, is not arm specific and properly supports unregistering (some handler with lower priority will take over). You can check gpio-restart as an example for the API.
If you have some other arm_pm_restart handler (those are tried first) I suggest to convert that to the restart handler framework. Actually it may be a good idea to convert all of them and drop arm_pm_restart, since there are only 4 left:
$ git grep "arm_pm_restart =" drivers/firmware/psci.c: arm_pm_restart = psci_sys_reset; arch/arm/mach-prima2/rstc.c: arm_pm_restart = sirfsoc_restart; arch/arm/xen/enlighten.c: arm_pm_restart = xen_restart; arch/arm/kernel/setup.c: arm_pm_restart = mdesc->restart;
The first 3 should be easy to update and the last one could be solved by registering a wrapper function as restart handler, which calls mdesc->restart().
> + return 0; > +}
This is missing a removal function, which should unregister the restart handler and do something like this:
if (pm_power_off == max77620_pm_power_off) pm_power_off = NULL;
> +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 <treding@nvidia.com>"); > +MODULE_ALIAS("platform:max77620-power"); > +MODULE_LICENSE("GPL v2"); > -- > 2.11.0
-- Sebastian [unhandled content-type:application/pgp-signature] | |