Commit 28124cc0 authored by Aurelien Jarno's avatar Aurelien Jarno Committed by Sebastian Reichel
Browse files

driver: reset: spacemit-p1: add driver for poweroff/reboot 



This driver implements poweroff/reboot support for the SpacemiT P1 PMIC
chip, which is commonly paired with the SpacemiT K1 SoC.

The SpacemiT P1 support is implemented as a MFD driver, so the access is
done directly through the regmap interface. Reboot or poweroff is
triggered by setting a specific bit in a control register, which is
automatically cleared by the hardware afterwards.

Signed-off-by: default avatarAurelien Jarno <aurelien@aurel32.net>
Link: https://patch.msgid.link/20251102230352.914421-2-aurelien@aurel32.net


Signed-off-by: default avatarSebastian Reichel <sebastian.reichel@collabora.com>
parent bd44ea12

drivers/power/reset/Kconfig

+9 −0
Original line number Diff line number Diff line
@@ -283,6 +283,15 @@ config POWER_RESET_KEYSTONE 
	help

	  Reboot support for the KEYSTONE SoCs.



config POWER_RESET_SPACEMIT_P1

	tristate "SpacemiT P1 poweroff and reset driver"

	depends on ARCH_SPACEMIT || COMPILE_TEST

	depends on MFD_SPACEMIT_P1

	default MFD_SPACEMIT_P1

	help

	  This driver supports power-off and reset operations for the SpacemiT

	  P1 PMIC.



config POWER_RESET_SYSCON

	bool "Generic SYSCON regmap reset driver"

	depends on OF

drivers/power/reset/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -24,6 +24,7 @@ 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_SPACEMIT_P1) += spacemit-p1-reboot.o

obj-$(CONFIG_POWER_RESET_ST) += st-poweroff.o

obj-$(CONFIG_POWER_RESET_TH1520_AON) += th1520-aon-reboot.o

obj-$(CONFIG_POWER_RESET_TORADEX_EC) += tdx-ec-poweroff.o

drivers/power/reset/spacemit-p1-reboot.c

0 → 100644
+88 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * Copyright (C) 2025 by Aurelien Jarno

 */



#include <linux/bits.h>

#include <linux/mod_devicetable.h>

#include <linux/platform_device.h>

#include <linux/regmap.h>

#include <linux/reboot.h>



/* Power Control Register 2 */

#define PWR_CTRL2		0x7e

#define PWR_CTRL2_SHUTDOWN	BIT(2)	/* Shutdown request */

#define PWR_CTRL2_RST		BIT(1)	/* Reset request */



static int spacemit_p1_pwroff_handler(struct sys_off_data *data)

{

	struct regmap *regmap = data->cb_data;

	int ret;



	/* Put the PMIC into shutdown state */

	ret = regmap_set_bits(regmap, PWR_CTRL2, PWR_CTRL2_SHUTDOWN);

	if (ret) {

		dev_err(data->dev, "shutdown failed: %d\n", ret);

		return notifier_from_errno(ret);

	}



	return NOTIFY_DONE;

}



static int spacemit_p1_restart_handler(struct sys_off_data *data)

{

	struct regmap *regmap = data->cb_data;

	int ret;



	/* Put the PMIC into reset state */

	ret = regmap_set_bits(regmap, PWR_CTRL2, PWR_CTRL2_RST);

	if (ret) {

		dev_err(data->dev, "restart failed: %d\n", ret);

		return notifier_from_errno(ret);

	}



	return NOTIFY_DONE;

}



static int spacemit_p1_reboot_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	struct regmap *regmap;

	int ret;



	regmap = dev_get_regmap(dev->parent, NULL);

	if (!regmap)

		return -ENODEV;



	ret = devm_register_power_off_handler(dev, &spacemit_p1_pwroff_handler,

					      regmap);

	if (ret)

		return dev_err_probe(dev, ret,

				     "Failed to register power off handler\n");



	ret = devm_register_restart_handler(dev, spacemit_p1_restart_handler,

					    regmap);

	if (ret)

		return dev_err_probe(dev, ret,

				     "Failed to register restart handler\n");



	return 0;

}



static const struct platform_device_id spacemit_p1_reboot_id_table[] = {

	{ "spacemit-p1-reboot", },

	{ /* sentinel */ },

};

MODULE_DEVICE_TABLE(platform, spacemit_p1_reboot_id_table);



static struct platform_driver spacemit_p1_reboot_driver = {

	.driver = {

		.name = "spacemit-p1-reboot",

	},

	.probe = spacemit_p1_reboot_probe,

	.id_table = spacemit_p1_reboot_id_table,

};

module_platform_driver(spacemit_p1_reboot_driver);



MODULE_DESCRIPTION("SpacemiT P1 reboot/poweroff driver");

MODULE_LICENSE("GPL");