1 /*
2 * Copyright (C) 2014 STMicroelectronics
3 *
4 * STMicroelectronics PHY driver for STiH41x USB.
5 *
6 * Author: Maxime Coquelin <maxime.coquelin@st.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2, as
10 * published by the Free Software Foundation.
11 *
12 */
13
14 #include <linux/platform_device.h>
15 #include <linux/io.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/of_platform.h>
20 #include <linux/clk.h>
21 #include <linux/phy/phy.h>
22 #include <linux/regmap.h>
23 #include <linux/mfd/syscon.h>
24
25 #define SYSCFG332 0x80
26 #define SYSCFG2520 0x820
27
28 /**
29 * struct stih41x_usb_cfg - SoC specific PHY register mapping
30 * @syscfg: Offset in syscfg registers bank
31 * @cfg_mask: Bits mask for PHY configuration
32 * @cfg: Static configuration value for PHY
33 * @oscok: Notify the PHY oscillator clock is ready
34 * Setting this bit enable the PHY
35 */
36 struct stih41x_usb_cfg {
37 u32 syscfg;
38 u32 cfg_mask;
39 u32 cfg;
40 u32 oscok;
41 };
42
43 /**
44 * struct stih41x_usb_phy - Private data for the PHY
45 * @dev: device for this controller
46 * @regmap: Syscfg registers bank in which PHY is configured
47 * @cfg: SoC specific PHY register mapping
48 * @clk: Oscillator used by the PHY
49 */
50 struct stih41x_usb_phy {
51 struct device *dev;
52 struct regmap *regmap;
53 const struct stih41x_usb_cfg *cfg;
54 struct clk *clk;
55 };
56
57 static struct stih41x_usb_cfg stih415_usb_phy_cfg = {
58 .syscfg = SYSCFG332,
59 .cfg_mask = 0x3f,
60 .cfg = 0x38,
61 .oscok = BIT(6),
62 };
63
64 static struct stih41x_usb_cfg stih416_usb_phy_cfg = {
65 .syscfg = SYSCFG2520,
66 .cfg_mask = 0x33f,
67 .cfg = 0x238,
68 .oscok = BIT(6),
69 };
70
stih41x_usb_phy_init(struct phy * phy)71 static int stih41x_usb_phy_init(struct phy *phy)
72 {
73 struct stih41x_usb_phy *phy_dev = phy_get_drvdata(phy);
74
75 return regmap_update_bits(phy_dev->regmap, phy_dev->cfg->syscfg,
76 phy_dev->cfg->cfg_mask, phy_dev->cfg->cfg);
77 }
78
stih41x_usb_phy_power_on(struct phy * phy)79 static int stih41x_usb_phy_power_on(struct phy *phy)
80 {
81 struct stih41x_usb_phy *phy_dev = phy_get_drvdata(phy);
82 int ret;
83
84 ret = clk_prepare_enable(phy_dev->clk);
85 if (ret) {
86 dev_err(phy_dev->dev, "Failed to enable osc_phy clock\n");
87 return ret;
88 }
89
90 ret = regmap_update_bits(phy_dev->regmap, phy_dev->cfg->syscfg,
91 phy_dev->cfg->oscok, phy_dev->cfg->oscok);
92 if (ret)
93 clk_disable_unprepare(phy_dev->clk);
94
95 return ret;
96 }
97
stih41x_usb_phy_power_off(struct phy * phy)98 static int stih41x_usb_phy_power_off(struct phy *phy)
99 {
100 struct stih41x_usb_phy *phy_dev = phy_get_drvdata(phy);
101 int ret;
102
103 ret = regmap_update_bits(phy_dev->regmap, phy_dev->cfg->syscfg,
104 phy_dev->cfg->oscok, 0);
105 if (ret) {
106 dev_err(phy_dev->dev, "Failed to clear oscok bit\n");
107 return ret;
108 }
109
110 clk_disable_unprepare(phy_dev->clk);
111
112 return 0;
113 }
114
115 static struct phy_ops stih41x_usb_phy_ops = {
116 .init = stih41x_usb_phy_init,
117 .power_on = stih41x_usb_phy_power_on,
118 .power_off = stih41x_usb_phy_power_off,
119 .owner = THIS_MODULE,
120 };
121
122 static const struct of_device_id stih41x_usb_phy_of_match[];
123
stih41x_usb_phy_probe(struct platform_device * pdev)124 static int stih41x_usb_phy_probe(struct platform_device *pdev)
125 {
126 struct device_node *np = pdev->dev.of_node;
127 const struct of_device_id *match;
128 struct stih41x_usb_phy *phy_dev;
129 struct device *dev = &pdev->dev;
130 struct phy_provider *phy_provider;
131 struct phy *phy;
132
133 phy_dev = devm_kzalloc(dev, sizeof(*phy_dev), GFP_KERNEL);
134 if (!phy_dev)
135 return -ENOMEM;
136
137 match = of_match_device(stih41x_usb_phy_of_match, &pdev->dev);
138 if (!match)
139 return -ENODEV;
140
141 phy_dev->cfg = match->data;
142
143 phy_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
144 if (IS_ERR(phy_dev->regmap)) {
145 dev_err(dev, "No syscfg phandle specified\n");
146 return PTR_ERR(phy_dev->regmap);
147 }
148
149 phy_dev->clk = devm_clk_get(dev, "osc_phy");
150 if (IS_ERR(phy_dev->clk)) {
151 dev_err(dev, "osc_phy clk not found\n");
152 return PTR_ERR(phy_dev->clk);
153 }
154
155 phy = devm_phy_create(dev, NULL, &stih41x_usb_phy_ops);
156
157 if (IS_ERR(phy)) {
158 dev_err(dev, "failed to create phy\n");
159 return PTR_ERR(phy);
160 }
161
162 phy_dev->dev = dev;
163
164 phy_set_drvdata(phy, phy_dev);
165
166 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
167 return PTR_ERR_OR_ZERO(phy_provider);
168 }
169
170 static const struct of_device_id stih41x_usb_phy_of_match[] = {
171 { .compatible = "st,stih415-usb-phy", .data = &stih415_usb_phy_cfg },
172 { .compatible = "st,stih416-usb-phy", .data = &stih416_usb_phy_cfg },
173 { /* sentinel */ },
174 };
175 MODULE_DEVICE_TABLE(of, stih41x_usb_phy_of_match);
176
177 static struct platform_driver stih41x_usb_phy_driver = {
178 .probe = stih41x_usb_phy_probe,
179 .driver = {
180 .name = "stih41x-usb-phy",
181 .of_match_table = stih41x_usb_phy_of_match,
182 }
183 };
184 module_platform_driver(stih41x_usb_phy_driver);
185
186 MODULE_AUTHOR("Maxime Coquelin <maxime.coquelin@st.com>");
187 MODULE_DESCRIPTION("STMicroelectronics USB PHY driver for STiH41x series");
188 MODULE_LICENSE("GPL v2");
189