// SPDX-License-Identifier: GPL-2.0-or-later/* * AR71xx Reset Controller Driver * Author: Alban Bedel * * Copyright (C) 2015 Alban Bedel <albeu@free.fr> */ #include <linux/io.h>#include <linux/init.h>#include <linux/platform_device.h>#include <linux/reset-controller.h>#include <linux/reboot.h> struct ath79_reset {	struct reset_controller_dev rcdev;	void __iomem *base;	spinlock_t lock;}; #define FULL_CHIP_RESET 24 static int ath79_reset_update(struct reset_controller_dev *rcdev,			unsigned long id, bool assert){	struct ath79_reset *ath79_reset =		container_of(rcdev, struct ath79_reset, rcdev);	unsigned long flags;	u32 val; 	spin_lock_irqsave(&ath79_reset->lock, flags);	val = readl(ath79_reset->base);	if (assert)		val |= BIT(id);	else		val &= ~BIT(id);	writel(val, ath79_reset->base);	spin_unlock_irqrestore(&ath79_reset->lock, flags); 	return 0;} static int ath79_reset_assert(struct reset_controller_dev *rcdev,			unsigned long id){	return ath79_reset_update(rcdev, id, true);} static int ath79_reset_deassert(struct reset_controller_dev *rcdev,				unsigned long id){	return ath79_reset_update(rcdev, id, false);} static int ath79_reset_status(struct reset_controller_dev *rcdev,			unsigned long id){	struct ath79_reset *ath79_reset =		container_of(rcdev, struct ath79_reset, rcdev);	u32 val; 	val = readl(ath79_reset->base); 	return !!(val & BIT(id));} static const struct reset_control_ops ath79_reset_ops = {	.assert = ath79_reset_assert,	.deassert = ath79_reset_deassert,	.status = ath79_reset_status,}; static int ath79_reset_restart_handler(struct sys_off_data *data){	struct ath79_reset *ath79_reset = data->cb_data; 	ath79_reset_assert(&ath79_reset->rcdev, FULL_CHIP_RESET); 	return NOTIFY_DONE;} static int ath79_reset_probe(struct platform_device *pdev){	struct ath79_reset *ath79_reset;	int err; 	ath79_reset = devm_kzalloc(&pdev->dev,				sizeof(*ath79_reset), GFP_KERNEL);	if (!ath79_reset)		return -ENOMEM; 	ath79_reset->base = devm_platform_ioremap_resource(pdev, 0);	if (IS_ERR(ath79_reset->base))		return PTR_ERR(ath79_reset->base); 	spin_lock_init(&ath79_reset->lock);	ath79_reset->rcdev.ops = &ath79_reset_ops;	ath79_reset->rcdev.owner = THIS_MODULE;	ath79_reset->rcdev.of_node = pdev->dev.of_node;	ath79_reset->rcdev.of_reset_n_cells = 1;	ath79_reset->rcdev.nr_resets = 32; 	err = devm_reset_controller_register(&pdev->dev, &ath79_reset->rcdev);	if (err)		return err; 	err = devm_register_restart_handler(&pdev->dev, ath79_reset_restart_handler, ath79_reset);	if (err)		dev_warn(&pdev->dev, "Failed to register restart handler\n"); 	return 0;} static const struct of_device_id ath79_reset_dt_ids[] = {	{ .compatible = "qca,ar7100-reset", },	{ },}; static struct platform_driver ath79_reset_driver = {	.probe	= ath79_reset_probe,	.driver = {		.name			= "ath79-reset",		.of_match_table		= ath79_reset_dt_ids,		.suppress_bind_attrs	= true,	},};builtin_platform_driver(ath79_reset_driver);