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