| /* |
| * drivers/reset/reset-oxnas.c |
| * |
| * Copyright (C) 2016 Neil Armstrong <narmstrong@baylibre.com> |
| * Copyright (C) 2014 Ma Haijun <mahaijuns@gmail.com> |
| * Copyright (C) 2009 Oxford Semiconductor Ltd |
| * |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms and conditions of the GNU General Public License, |
| * version 2, as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| * more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| #include <linux/err.h> |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/platform_device.h> |
| #include <linux/reset-controller.h> |
| #include <linux/slab.h> |
| #include <linux/delay.h> |
| #include <linux/types.h> |
| #include <linux/regmap.h> |
| #include <linux/mfd/syscon.h> |
| |
| /* Regmap offsets */ |
| #define RST_SET_REGOFFSET 0x34 |
| #define RST_CLR_REGOFFSET 0x38 |
| |
| struct oxnas_reset { |
| struct regmap *regmap; |
| struct reset_controller_dev rcdev; |
| }; |
| |
| static int oxnas_reset_reset(struct reset_controller_dev *rcdev, |
| unsigned long id) |
| { |
| struct oxnas_reset *data = |
| container_of(rcdev, struct oxnas_reset, rcdev); |
| |
| regmap_write(data->regmap, RST_SET_REGOFFSET, BIT(id)); |
| msleep(50); |
| regmap_write(data->regmap, RST_CLR_REGOFFSET, BIT(id)); |
| |
| return 0; |
| } |
| |
| static int oxnas_reset_assert(struct reset_controller_dev *rcdev, |
| unsigned long id) |
| { |
| struct oxnas_reset *data = |
| container_of(rcdev, struct oxnas_reset, rcdev); |
| |
| regmap_write(data->regmap, RST_SET_REGOFFSET, BIT(id)); |
| |
| return 0; |
| } |
| |
| static int oxnas_reset_deassert(struct reset_controller_dev *rcdev, |
| unsigned long id) |
| { |
| struct oxnas_reset *data = |
| container_of(rcdev, struct oxnas_reset, rcdev); |
| |
| regmap_write(data->regmap, RST_CLR_REGOFFSET, BIT(id)); |
| |
| return 0; |
| } |
| |
| static const struct reset_control_ops oxnas_reset_ops = { |
| .reset = oxnas_reset_reset, |
| .assert = oxnas_reset_assert, |
| .deassert = oxnas_reset_deassert, |
| }; |
| |
| static const struct of_device_id oxnas_reset_dt_ids[] = { |
| { .compatible = "oxsemi,ox810se-reset", }, |
| { /* sentinel */ }, |
| }; |
| MODULE_DEVICE_TABLE(of, oxnas_reset_dt_ids); |
| |
| static int oxnas_reset_probe(struct platform_device *pdev) |
| { |
| struct oxnas_reset *data; |
| struct device *parent; |
| |
| parent = pdev->dev.parent; |
| if (!parent) { |
| dev_err(&pdev->dev, "no parent\n"); |
| return -ENODEV; |
| } |
| |
| data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); |
| if (!data) |
| return -ENOMEM; |
| |
| data->regmap = syscon_node_to_regmap(parent->of_node); |
| if (IS_ERR(data->regmap)) { |
| dev_err(&pdev->dev, "failed to get parent regmap\n"); |
| return PTR_ERR(data->regmap); |
| } |
| |
| platform_set_drvdata(pdev, data); |
| |
| data->rcdev.owner = THIS_MODULE; |
| data->rcdev.nr_resets = 32; |
| data->rcdev.ops = &oxnas_reset_ops; |
| data->rcdev.of_node = pdev->dev.of_node; |
| |
| return reset_controller_register(&data->rcdev); |
| } |
| |
| static int oxnas_reset_remove(struct platform_device *pdev) |
| { |
| struct oxnas_reset *data = platform_get_drvdata(pdev); |
| |
| reset_controller_unregister(&data->rcdev); |
| |
| return 0; |
| } |
| |
| static struct platform_driver oxnas_reset_driver = { |
| .probe = oxnas_reset_probe, |
| .remove = oxnas_reset_remove, |
| .driver = { |
| .name = "oxnas-reset", |
| .of_match_table = oxnas_reset_dt_ids, |
| }, |
| }; |
| |
| module_platform_driver(oxnas_reset_driver); |