/* * Copyright (C) 2014 Marvell Technology Group Ltd. * * Marvell Berlin reset driver * * Antoine Tenart <antoine.tenart@free-electrons.com> * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com> * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #include <linux/delay.h>#include <linux/io.h>#include <linux/mfd/syscon.h>#include <linux/module.h>#include <linux/of.h>#include <linux/of_address.h>#include <linux/platform_device.h>#include <linux/regmap.h>#include <linux/reset-controller.h>#include <linux/slab.h>#include <linux/types.h> #define BERLIN_MAX_RESETS	32 #define to_berlin_reset_priv(p)		\	container_of((p), struct berlin_reset_priv, rcdev) struct berlin_reset_priv {	struct regmap			*regmap;	struct reset_controller_dev	rcdev;}; static int berlin_reset_reset(struct reset_controller_dev *rcdev,			      unsigned long id){	struct berlin_reset_priv *priv = to_berlin_reset_priv(rcdev);	int offset = id >> 8;	int mask = BIT(id & 0x1f); 	regmap_write(priv->regmap, offset, mask); 	/* let the reset be effective */	udelay(10); 	return 0;} static const struct reset_control_ops berlin_reset_ops = {	.reset	= berlin_reset_reset,}; static int berlin_reset_xlate(struct reset_controller_dev *rcdev,			      const struct of_phandle_args *reset_spec){	unsigned int offset, bit; 	offset = reset_spec->args[0];	bit = reset_spec->args[1]; 	if (bit >= BERLIN_MAX_RESETS)		return -EINVAL; 	return (offset << 8) | bit;} static int berlin2_reset_probe(struct platform_device *pdev){	struct device_node *parent_np;	struct berlin_reset_priv *priv; 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);	if (!priv)		return -ENOMEM; 	parent_np = of_get_parent(pdev->dev.of_node);	priv->regmap = syscon_node_to_regmap(parent_np);	of_node_put(parent_np);	if (IS_ERR(priv->regmap))		return PTR_ERR(priv->regmap); 	priv->rcdev.owner = THIS_MODULE;	priv->rcdev.ops = &berlin_reset_ops;	priv->rcdev.of_node = pdev->dev.of_node;	priv->rcdev.of_reset_n_cells = 2;	priv->rcdev.of_xlate = berlin_reset_xlate; 	return reset_controller_register(&priv->rcdev);} static const struct of_device_id berlin_reset_dt_match[] = {	{ .compatible = "marvell,berlin2-reset" },	{ },};MODULE_DEVICE_TABLE(of, berlin_reset_dt_match); static struct platform_driver berlin_reset_driver = {	.probe	= berlin2_reset_probe,	.driver	= {		.name = "berlin2-reset",		.of_match_table = berlin_reset_dt_match,	},};module_platform_driver(berlin_reset_driver); MODULE_AUTHOR("Antoine Tenart <antoine.tenart@free-electrons.com>");MODULE_AUTHOR("Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>");MODULE_DESCRIPTION("Synaptics Berlin reset controller");MODULE_LICENSE("GPL");