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_device.h>
10 #include <linux/platform_device.h>
11 #include <linux/reset.h>
12 
13 #include "reset-simple.h"
14 
15 #define MAX_CLKS	2
16 #define MAX_RSTS	2
17 
18 struct uniphier_glue_reset_soc_data {
19 	int nclks;
20 	const char * const *clock_names;
21 	int nrsts;
22 	const char * const *reset_names;
23 };
24 
25 struct uniphier_glue_reset_priv {
26 	struct clk_bulk_data clk[MAX_CLKS];
27 	struct reset_control *rst[MAX_RSTS];
28 	struct reset_simple_data rdata;
29 	const struct uniphier_glue_reset_soc_data *data;
30 };
31 
32 static int uniphier_glue_reset_probe(struct platform_device *pdev)
33 {
34 	struct device *dev = &pdev->dev;
35 	struct uniphier_glue_reset_priv *priv;
36 	struct resource *res;
37 	resource_size_t size;
38 	const char *name;
39 	int i, ret, nr;
40 
41 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
42 	if (!priv)
43 		return -ENOMEM;
44 
45 	priv->data = of_device_get_match_data(dev);
46 	if (WARN_ON(!priv->data || priv->data->nclks > MAX_CLKS ||
47 		    priv->data->nrsts > MAX_RSTS))
48 		return -EINVAL;
49 
50 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
51 	size = resource_size(res);
52 	priv->rdata.membase = devm_ioremap_resource(dev, res);
53 	if (IS_ERR(priv->rdata.membase))
54 		return PTR_ERR(priv->rdata.membase);
55 
56 	for (i = 0; i < priv->data->nclks; i++)
57 		priv->clk[i].id = priv->data->clock_names[i];
58 	ret = devm_clk_bulk_get(dev, priv->data->nclks, priv->clk);
59 	if (ret)
60 		return ret;
61 
62 	for (i = 0; i < priv->data->nrsts; i++) {
63 		name = priv->data->reset_names[i];
64 		priv->rst[i] = devm_reset_control_get_shared(dev, name);
65 		if (IS_ERR(priv->rst[i]))
66 			return PTR_ERR(priv->rst[i]);
67 	}
68 
69 	ret = clk_bulk_prepare_enable(priv->data->nclks, priv->clk);
70 	if (ret)
71 		return ret;
72 
73 	for (nr = 0; nr < priv->data->nrsts; nr++) {
74 		ret = reset_control_deassert(priv->rst[nr]);
75 		if (ret)
76 			goto out_rst_assert;
77 	}
78 
79 	spin_lock_init(&priv->rdata.lock);
80 	priv->rdata.rcdev.owner = THIS_MODULE;
81 	priv->rdata.rcdev.nr_resets = size * BITS_PER_BYTE;
82 	priv->rdata.rcdev.ops = &reset_simple_ops;
83 	priv->rdata.rcdev.of_node = dev->of_node;
84 	priv->rdata.active_low = true;
85 
86 	platform_set_drvdata(pdev, priv);
87 
88 	ret = devm_reset_controller_register(dev, &priv->rdata.rcdev);
89 	if (ret)
90 		goto out_rst_assert;
91 
92 	return 0;
93 
94 out_rst_assert:
95 	while (nr--)
96 		reset_control_assert(priv->rst[nr]);
97 
98 	clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
99 
100 	return ret;
101 }
102 
103 static int uniphier_glue_reset_remove(struct platform_device *pdev)
104 {
105 	struct uniphier_glue_reset_priv *priv = platform_get_drvdata(pdev);
106 	int i;
107 
108 	for (i = 0; i < priv->data->nrsts; i++)
109 		reset_control_assert(priv->rst[i]);
110 
111 	clk_bulk_disable_unprepare(priv->data->nclks, priv->clk);
112 
113 	return 0;
114 }
115 
116 static const char * const uniphier_pro4_clock_reset_names[] = {
117 	"gio", "link",
118 };
119 
120 static const struct uniphier_glue_reset_soc_data uniphier_pro4_data = {
121 	.nclks = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
122 	.clock_names = uniphier_pro4_clock_reset_names,
123 	.nrsts = ARRAY_SIZE(uniphier_pro4_clock_reset_names),
124 	.reset_names = uniphier_pro4_clock_reset_names,
125 };
126 
127 static const char * const uniphier_pxs2_clock_reset_names[] = {
128 	"link",
129 };
130 
131 static const struct uniphier_glue_reset_soc_data uniphier_pxs2_data = {
132 	.nclks = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
133 	.clock_names = uniphier_pxs2_clock_reset_names,
134 	.nrsts = ARRAY_SIZE(uniphier_pxs2_clock_reset_names),
135 	.reset_names = uniphier_pxs2_clock_reset_names,
136 };
137 
138 static const struct of_device_id uniphier_glue_reset_match[] = {
139 	{
140 		.compatible = "socionext,uniphier-pro4-usb3-reset",
141 		.data = &uniphier_pro4_data,
142 	},
143 	{
144 		.compatible = "socionext,uniphier-pxs2-usb3-reset",
145 		.data = &uniphier_pxs2_data,
146 	},
147 	{
148 		.compatible = "socionext,uniphier-ld20-usb3-reset",
149 		.data = &uniphier_pxs2_data,
150 	},
151 	{
152 		.compatible = "socionext,uniphier-pxs3-usb3-reset",
153 		.data = &uniphier_pxs2_data,
154 	},
155 	{
156 		.compatible = "socionext,uniphier-pro4-ahci-reset",
157 		.data = &uniphier_pro4_data,
158 	},
159 	{
160 		.compatible = "socionext,uniphier-pxs2-ahci-reset",
161 		.data = &uniphier_pxs2_data,
162 	},
163 	{
164 		.compatible = "socionext,uniphier-pxs3-ahci-reset",
165 		.data = &uniphier_pxs2_data,
166 	},
167 	{ /* Sentinel */ }
168 };
169 MODULE_DEVICE_TABLE(of, uniphier_glue_reset_match);
170 
171 static struct platform_driver uniphier_glue_reset_driver = {
172 	.probe = uniphier_glue_reset_probe,
173 	.remove = uniphier_glue_reset_remove,
174 	.driver = {
175 		.name = "uniphier-glue-reset",
176 		.of_match_table = uniphier_glue_reset_match,
177 	},
178 };
179 module_platform_driver(uniphier_glue_reset_driver);
180 
181 MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
182 MODULE_DESCRIPTION("UniPhier Glue layer reset driver");
183 MODULE_LICENSE("GPL");
184