diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/power/reset/Kconfig | 7 | ||||
| -rw-r--r-- | drivers/power/reset/Makefile | 1 | ||||
| -rw-r--r-- | drivers/power/reset/regulator-poweroff.c | 82 |
3 files changed, 90 insertions, 0 deletions
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index d55b3727e00e..b22c4fdb2561 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -177,6 +177,13 @@ config POWER_RESET_QNAP Say Y if you have a QNAP NAS. +config POWER_RESET_REGULATOR + bool "Regulator subsystem power-off driver" + depends on OF && REGULATOR + help + This driver supports turning off your board by disabling a + power regulator defined in the devicetree. + config POWER_RESET_RESTART bool "Restart power-off driver" help diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index c51eceba9ea3..9dc49d3a57ff 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_POWER_RESET_OCELOT_RESET) += ocelot-reset.o obj-$(CONFIG_POWER_RESET_PIIX4_POWEROFF) += piix4-poweroff.o obj-$(CONFIG_POWER_RESET_LTC2952) += ltc2952-poweroff.o obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o +obj-$(CONFIG_POWER_RESET_REGULATOR) += regulator-poweroff.o obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o obj-$(CONFIG_POWER_RESET_ST) += st-poweroff.o obj-$(CONFIG_POWER_RESET_VERSATILE) += arm-versatile-reboot.o diff --git a/drivers/power/reset/regulator-poweroff.c b/drivers/power/reset/regulator-poweroff.c new file mode 100644 index 000000000000..f697088e0ad1 --- /dev/null +++ b/drivers/power/reset/regulator-poweroff.c @@ -0,0 +1,82 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Force-disables a regulator to power down a device + * + * Michael Klein <michael@fossekall.de> + * + * Copyright (C) 2020 Michael Klein + * + * Based on the gpio-poweroff driver. + */ +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/regulator/consumer.h> + +#define TIMEOUT_MS 3000 + +/* + * Hold configuration here, cannot be more than one instance of the driver + * since pm_power_off itself is global. + */ +static struct regulator *cpu_regulator; + +static void regulator_poweroff_do_poweroff(void) +{ + if (cpu_regulator && regulator_is_enabled(cpu_regulator)) + regulator_force_disable(cpu_regulator); + + /* give it some time */ + mdelay(TIMEOUT_MS); + + WARN_ON(1); +} + +static int regulator_poweroff_probe(struct platform_device *pdev) +{ + /* If a pm_power_off function has already been added, leave it alone */ + if (pm_power_off != NULL) { + dev_err(&pdev->dev, + "%s: pm_power_off function already registered\n", + __func__); + return -EBUSY; + } + + cpu_regulator = devm_regulator_get(&pdev->dev, "cpu"); + if (IS_ERR(cpu_regulator)) + return PTR_ERR(cpu_regulator); + + pm_power_off = ®ulator_poweroff_do_poweroff; + return 0; +} + +static int regulator_poweroff_remove(__maybe_unused struct platform_device *pdev) +{ + if (pm_power_off == ®ulator_poweroff_do_poweroff) + pm_power_off = NULL; + + return 0; +} + +static const struct of_device_id of_regulator_poweroff_match[] = { + { .compatible = "regulator-poweroff", }, + {}, +}; + +static struct platform_driver regulator_poweroff_driver = { + .probe = regulator_poweroff_probe, + .remove = regulator_poweroff_remove, + .driver = { + .name = "poweroff-regulator", + .of_match_table = of_regulator_poweroff_match, + }, +}; + +module_platform_driver(regulator_poweroff_driver); + +MODULE_AUTHOR("Michael Klein <michael@fossekall.de>"); +MODULE_DESCRIPTION("Regulator poweroff driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:poweroff-regulator"); |