[linux-block.git] / drivers / reset / reset-k210.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (c) 2020 Western Digital Corporation or its affiliates.
 */
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/reset-controller.h>
#include <linux/delay.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <soc/canaan/k210-sysctl.h>

#include <dt-bindings/reset/k210-rst.h>

#define K210_RST_MASK	0x27FFFFFF

struct k210_rst {
	struct regmap *map;
	struct reset_controller_dev rcdev;
};

static inline struct k210_rst *
to_k210_rst(struct reset_controller_dev *rcdev)
{
	return container_of(rcdev, struct k210_rst, rcdev);
}

static inline int k210_rst_assert(struct reset_controller_dev *rcdev,
				  unsigned long id)
{
	struct k210_rst *ksr = to_k210_rst(rcdev);

	return regmap_update_bits(ksr->map, K210_SYSCTL_PERI_RESET, BIT(id), 1);
}

static inline int k210_rst_deassert(struct reset_controller_dev *rcdev,
				    unsigned long id)
{
	struct k210_rst *ksr = to_k210_rst(rcdev);

	return regmap_update_bits(ksr->map, K210_SYSCTL_PERI_RESET, BIT(id), 0);
}

static int k210_rst_reset(struct reset_controller_dev *rcdev,
			  unsigned long id)
{
	int ret;

	ret = k210_rst_assert(rcdev, id);
	if (ret == 0) {
		udelay(10);
		ret = k210_rst_deassert(rcdev, id);
	}

	return ret;
}

static int k210_rst_status(struct reset_controller_dev *rcdev,
			   unsigned long id)
{
	struct k210_rst *ksr = to_k210_rst(rcdev);
	u32 reg, bit = BIT(id);
	int ret;

	ret = regmap_read(ksr->map, K210_SYSCTL_PERI_RESET, &reg);
	if (ret)
		return ret;

	return reg & bit;
}

static int k210_rst_xlate(struct reset_controller_dev *rcdev,
			  const struct of_phandle_args *reset_spec)
{
	unsigned long id = reset_spec->args[0];

	if (!(BIT(id) & K210_RST_MASK))
		return -EINVAL;

	return id;
}

static const struct reset_control_ops k210_rst_ops = {
	.assert		= k210_rst_assert,
	.deassert	= k210_rst_deassert,
	.reset		= k210_rst_reset,
	.status		= k210_rst_status,
};

static int k210_rst_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct device_node *parent_np = of_get_parent(dev->of_node);
	struct k210_rst *ksr;

	dev_info(dev, "K210 reset controller\n");

	ksr = devm_kzalloc(dev, sizeof(*ksr), GFP_KERNEL);
	if (!ksr)
		return -ENOMEM;

	ksr->map = syscon_node_to_regmap(parent_np);
	of_node_put(parent_np);
	if (IS_ERR(ksr->map))
		return PTR_ERR(ksr->map);

	ksr->rcdev.owner = THIS_MODULE;
	ksr->rcdev.dev = dev;
	ksr->rcdev.of_node = dev->of_node;
	ksr->rcdev.ops = &k210_rst_ops;
	ksr->rcdev.nr_resets = fls(K210_RST_MASK);
	ksr->rcdev.of_reset_n_cells = 1;
	ksr->rcdev.of_xlate = k210_rst_xlate;

	return devm_reset_controller_register(dev, &ksr->rcdev);
}

static const struct of_device_id k210_rst_dt_ids[] = {
	{ .compatible = "canaan,k210-rst" },
	{ /* sentinel */ },
};

static struct platform_driver k210_rst_driver = {
	.probe	= k210_rst_probe,
	.driver = {
		.name		= "k210-rst",
		.of_match_table	= k210_rst_dt_ids,
	},
};
builtin_platform_driver(k210_rst_driver);
Commit	Line	Data
5a2308da DLM	1	// SPDX-License-Identifier: GPL-2.0-or-later
	2	/*
	3	* Copyright (c) 2020 Western Digital Corporation or its affiliates.
	4	*/
	5	#include <linux/of.h>
	6	#include <linux/of_device.h>
	7	#include <linux/platform_device.h>
	8	#include <linux/reset-controller.h>
	9	#include <linux/delay.h>
	10	#include <linux/mfd/syscon.h>
	11	#include <linux/regmap.h>
	12	#include <soc/canaan/k210-sysctl.h>
	13
	14	#include <dt-bindings/reset/k210-rst.h>
	15
	16	#define K210_RST_MASK 0x27FFFFFF
	17
	18	struct k210_rst {
	19	struct regmap *map;
	20	struct reset_controller_dev rcdev;
	21	};
	22
	23	static inline struct k210_rst *
	24	to_k210_rst(struct reset_controller_dev *rcdev)
	25	{
	26	return container_of(rcdev, struct k210_rst, rcdev);
	27	}
	28
	29	static inline int k210_rst_assert(struct reset_controller_dev *rcdev,
	30	unsigned long id)
	31	{
	32	struct k210_rst *ksr = to_k210_rst(rcdev);
	33
	34	return regmap_update_bits(ksr->map, K210_SYSCTL_PERI_RESET, BIT(id), 1);
	35	}
	36
	37	static inline int k210_rst_deassert(struct reset_controller_dev *rcdev,
	38	unsigned long id)
	39	{
	40	struct k210_rst *ksr = to_k210_rst(rcdev);
	41
	42	return regmap_update_bits(ksr->map, K210_SYSCTL_PERI_RESET, BIT(id), 0);
	43	}
	44
	45	static int k210_rst_reset(struct reset_controller_dev *rcdev,
	46	unsigned long id)
	47	{
	48	int ret;
	49
	50	ret = k210_rst_assert(rcdev, id);
	51	if (ret == 0) {
	52	udelay(10);
	53	ret = k210_rst_deassert(rcdev, id);
	54	}
	55
	56	return ret;
	57	}
	58
	59	static int k210_rst_status(struct reset_controller_dev *rcdev,
	60	unsigned long id)
	61	{
	62	struct k210_rst *ksr = to_k210_rst(rcdev);
	63	u32 reg, bit = BIT(id);
	64	int ret;
65
66	ret = regmap_read(ksr->map, K210_SYSCTL_PERI_RESET, &reg);
67	if (ret)
68	return ret;
69
70	return reg & bit;
71	}
72
73	static int k210_rst_xlate(struct reset_controller_dev *rcdev,
74	const struct of_phandle_args *reset_spec)
75	{
76	unsigned long id = reset_spec->args[0];
77
78	if (!(BIT(id) & K210_RST_MASK))
79	return -EINVAL;
80
81	return id;
82	}
83
84	static const struct reset_control_ops k210_rst_ops = {
85	.assert = k210_rst_assert,
86	.deassert = k210_rst_deassert,
87	.reset = k210_rst_reset,
88	.status = k210_rst_status,
89	};
90
91	static int k210_rst_probe(struct platform_device *pdev)
92	{
93	struct device *dev = &pdev->dev;
94	struct device_node *parent_np = of_get_parent(dev->of_node);
95	struct k210_rst *ksr;
96
97	dev_info(dev, "K210 reset controller\n");
98
99	ksr = devm_kzalloc(dev, sizeof(*ksr), GFP_KERNEL);
100	if (!ksr)
101	return -ENOMEM;
102
103	ksr->map = syscon_node_to_regmap(parent_np);
104	of_node_put(parent_np);
105	if (IS_ERR(ksr->map))
106	return PTR_ERR(ksr->map);
107
108	ksr->rcdev.owner = THIS_MODULE;
109	ksr->rcdev.dev = dev;
110	ksr->rcdev.of_node = dev->of_node;
111	ksr->rcdev.ops = &k210_rst_ops;
112	ksr->rcdev.nr_resets = fls(K210_RST_MASK);
113	ksr->rcdev.of_reset_n_cells = 1;
114	ksr->rcdev.of_xlate = k210_rst_xlate;
115
116	return devm_reset_controller_register(dev, &ksr->rcdev);
117	}
118
119	static const struct of_device_id k210_rst_dt_ids[] = {
120	{ .compatible = "canaan,k210-rst" },
121	{ /* sentinel */ },
122	};
123
124	static struct platform_driver k210_rst_driver = {
125	.probe = k210_rst_probe,
126	.driver = {
127	.name = "k210-rst",
128	.of_match_table = k210_rst_dt_ids,
129	},
130	};
131	builtin_platform_driver(k210_rst_driver);