1// SPDX-License-Identifier: GPL-2.0
2//
3// reset-uniphier-glue.c - Glue layer reset driver for UniPhier
4// Copyright 2018 Socionext Inc.
5// Author: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
6
7#include <linux/clk.h>
8#include <linux/module.h>
9#include <linux/of.h>
10#include <linux/platform_device.h>
11#include <linux/reset.h>
12#include <linux/reset/reset-simple.h>
13
14#define MAX_CLKS	2
15#define MAX_RSTS	2
16
17struct uniphier_glue_reset_soc_data {
18	int nclks;
19	const char * const *clock_names;
20	int nrsts;
21	const char * const *reset_names;
22};
23
24struct uniphier_glue_reset_priv {
25	struct clk_bulk_data clk[MAX_CLKS];
26	struct reset_control_bulk_data rst[MAX_RSTS];
27	struct reset_simple_data rdata;
28	const struct uniphier_glue_reset_soc_data *data;
29};
30
31static void uniphier_clk_disable(void *_priv)
32{
33	struct uniphier_glue_reset_priv *priv = _priv;
34
35	clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
36}
37
38static void uniphier_rst_assert(void *_priv)
39{
40	struct uniphier_glue_reset_priv *priv = _priv;
41
42	reset_control_bulk_assert(priv->data->nrsts, priv->rst);
43}
44
45static int uniphier_glue_reset_probe(struct platform_device *pdev)
46{
47	struct device *dev = &pdev->dev;
48	struct uniphier_glue_reset_priv *priv;
49	struct resource *res;
50	int i, ret;
51
52	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
53	if (!priv)
54		return -ENOMEM;
55
56	priv->data = of_device_get_match_data(dev);
57	if (WARN_ON(!priv->data || priv->data->nclks > MAX_CLKS ||
58		    priv->data->nrsts > MAX_RSTS))
59		return -EINVAL;
60
61	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
62	priv->rdata.membase = devm_ioremap_resource(dev, res);
63	if (IS_ERR(priv->rdata.membase))
64		return PTR_ERR(priv->rdata.membase);
65
66	for (i = 0; i < priv->data->nclks; i++)
67		priv->clk[i].id = priv->data->clock_names[i];
68	ret = devm_clk_bulk_get(dev, priv->data->nclks, priv->clk);
69	if (ret)
70		return ret;
71
72	for (i = 0; i < priv->data->nrsts; i++)
73		priv->rst[i].id = priv->data->reset_names[i];
74	ret = devm_reset_control_bulk_get_shared(dev, priv->data->nrsts,
75						 priv->rst);
76	if (ret)
77		return ret;
78
79	ret = clk_bulk_prepare_enable(priv->data->nclks, priv->clk);
80	if (ret)
81		return ret;
82
83	ret = devm_add_action_or_reset(dev, uniphier_clk_disable, priv);
84	if (ret)
85		return ret;
86
87	ret = reset_control_bulk_deassert(priv->data->nrsts, priv->rst);
88	if (ret)
89		return ret;
90
91	ret = devm_add_action_or_reset(dev, uniphier_rst_assert, priv);
92	if (ret)
93		return ret;
94
95	spin_lock_init(&priv->rdata.lock);
96	priv->rdata.rcdev.owner = THIS_MODULE;
97	priv->rdata.rcdev.nr_resets = resource_size(res) * BITS_PER_BYTE;
98	priv->rdata.rcdev.ops = &reset_simple_ops;
99	priv->rdata.rcdev.of_node = dev->of_node;
100	priv->rdata.active_low = true;
101
102	return devm_reset_controller_register(dev, &priv->rdata.rcdev);
103}
104
105static const char * const uniphier_pro4_clock_reset_names[] = {
106	"gio", "link",
107};
108
109static const struct uniphier_glue_reset_soc_data uniphier_pro4_data = {
110	.nclks = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
111	.clock_names = uniphier_pro4_clock_reset_names,
112	.nrsts = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
113	.reset_names = uniphier_pro4_clock_reset_names,
114};
115
116static const char * const uniphier_pxs2_clock_reset_names[] = {
117	"link",
118};
119
120static const struct uniphier_glue_reset_soc_data uniphier_pxs2_data = {
121	.nclks = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
122	.clock_names = uniphier_pxs2_clock_reset_names,
123	.nrsts = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
124	.reset_names = uniphier_pxs2_clock_reset_names,
125};
126
127static const struct of_device_id uniphier_glue_reset_match[] = {
128	{
129		.compatible = "socionext,uniphier-pro4-usb3-reset",
130		.data = &uniphier_pro4_data,
131	},
132	{
133		.compatible = "socionext,uniphier-pro5-usb3-reset",
134		.data = &uniphier_pro4_data,
135	},
136	{
137		.compatible = "socionext,uniphier-pxs2-usb3-reset",
138		.data = &uniphier_pxs2_data,
139	},
140	{
141		.compatible = "socionext,uniphier-ld20-usb3-reset",
142		.data = &uniphier_pxs2_data,
143	},
144	{
145		.compatible = "socionext,uniphier-pxs3-usb3-reset",
146		.data = &uniphier_pxs2_data,
147	},
148	{
149		.compatible = "socionext,uniphier-nx1-usb3-reset",
150		.data = &uniphier_pxs2_data,
151	},
152	{
153		.compatible = "socionext,uniphier-pro4-ahci-reset",
154		.data = &uniphier_pro4_data,
155	},
156	{
157		.compatible = "socionext,uniphier-pxs2-ahci-reset",
158		.data = &uniphier_pxs2_data,
159	},
160	{
161		.compatible = "socionext,uniphier-pxs3-ahci-reset",
162		.data = &uniphier_pxs2_data,
163	},
164	{ /* Sentinel */ }
165};
166MODULE_DEVICE_TABLE(of, uniphier_glue_reset_match);
167
168static struct platform_driver uniphier_glue_reset_driver = {
169	.probe = uniphier_glue_reset_probe,
170	.driver = {
171		.name = "uniphier-glue-reset",
172		.of_match_table = uniphier_glue_reset_match,
173	},
174};
175module_platform_driver(uniphier_glue_reset_driver);
176
177MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
178MODULE_DESCRIPTION("UniPhier Glue layer reset driver");
179MODULE_LICENSE("GPL");
180