diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/reset/reset-oxnas.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/drivers/reset/reset-oxnas.c b/drivers/reset/reset-oxnas.c new file mode 100644 index 000000000..cf5b9742b --- /dev/null +++ b/drivers/reset/reset-oxnas.c @@ -0,0 +1,125 @@ +/* + * 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/init.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", }, + { .compatible = "oxsemi,ox820-reset", }, + { /* sentinel */ }, +}; + +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 devm_reset_controller_register(&pdev->dev, &data->rcdev); +} + +static struct platform_driver oxnas_reset_driver = { + .probe = oxnas_reset_probe, + .driver = { + .name = "oxnas-reset", + .of_match_table = oxnas_reset_dt_ids, + }, +}; +builtin_platform_driver(oxnas_reset_driver); |