/* * Allwinner SoCs Reset Controller driver * * Copyright 2013 Maxime Ripard * * Maxime Ripard <maxime.ripard@free-electrons.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; either version 2 of the License, or * (at your option) any later version. */ #include <linux/err.h> #include <linux/io.h> #include <linux/init.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/platform_device.h> #include <linux/reset-controller.h> #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/types.h> #include "reset-simple.h" static int sunxi_reset_init(struct device_node *np) { struct reset_simple_data *data; struct resource res; resource_size_t size; int ret; data = kzalloc(sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; ret = of_address_to_resource(np, 0, &res); if (ret) goto err_alloc; size = resource_size(&res); if (!request_mem_region(res.start, size, np->name)) { ret = -EBUSY; goto err_alloc; } data->membase = ioremap(res.start, size); if (!data->membase) { ret = -ENOMEM; goto err_alloc; } spin_lock_init(&data->lock); data->rcdev.owner = THIS_MODULE; data->rcdev.nr_resets = size * 8; data->rcdev.ops = &reset_simple_ops; data->rcdev.of_node = np; data->active_low = true; return reset_controller_register(&data->rcdev); err_alloc: kfree(data); return ret; }; /* * These are the reset controller we need to initialize early on in * our system, before we can even think of using a regular device * driver for it. * The controllers that we can register through the regular device * model are handled by the simple reset driver directly. */ static const struct of_device_id sunxi_early_reset_dt_ids[] __initconst = { { .compatible = "allwinner,sun6i-a31-ahb1-reset", }, { /* sentinel */ }, }; void __init sun6i_reset_init(void) { struct device_node *np; for_each_matching_node(np, sunxi_early_reset_dt_ids) sunxi_reset_init(np); }