1 /*
2 * Rockchip usb PHY driver
3 *
4 * Copyright (C) 2014 Yunzhi Li <lyz@rock-chips.com>
5 * Copyright (C) 2014 ROCKCHIP, Inc.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 */
16
17 #include <linux/clk.h>
18 #include <linux/io.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/mutex.h>
22 #include <linux/of.h>
23 #include <linux/of_address.h>
24 #include <linux/phy/phy.h>
25 #include <linux/platform_device.h>
26 #include <linux/regulator/consumer.h>
27 #include <linux/reset.h>
28 #include <linux/regmap.h>
29 #include <linux/mfd/syscon.h>
30
31 /*
32 * The higher 16-bit of this register is used for write protection
33 * only if BIT(13 + 16) set to 1 the BIT(13) can be written.
34 */
35 #define SIDDQ_WRITE_ENA BIT(29)
36 #define SIDDQ_ON BIT(13)
37 #define SIDDQ_OFF (0 << 13)
38
39 struct rockchip_usb_phy {
40 unsigned int reg_offset;
41 struct regmap *reg_base;
42 struct clk *clk;
43 struct phy *phy;
44 };
45
rockchip_usb_phy_power(struct rockchip_usb_phy * phy,bool siddq)46 static int rockchip_usb_phy_power(struct rockchip_usb_phy *phy,
47 bool siddq)
48 {
49 return regmap_write(phy->reg_base, phy->reg_offset,
50 SIDDQ_WRITE_ENA | (siddq ? SIDDQ_ON : SIDDQ_OFF));
51 }
52
rockchip_usb_phy_power_off(struct phy * _phy)53 static int rockchip_usb_phy_power_off(struct phy *_phy)
54 {
55 struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
56 int ret = 0;
57
58 /* Power down usb phy analog blocks by set siddq 1 */
59 ret = rockchip_usb_phy_power(phy, 1);
60 if (ret)
61 return ret;
62
63 clk_disable_unprepare(phy->clk);
64
65 return 0;
66 }
67
rockchip_usb_phy_power_on(struct phy * _phy)68 static int rockchip_usb_phy_power_on(struct phy *_phy)
69 {
70 struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
71 int ret = 0;
72
73 ret = clk_prepare_enable(phy->clk);
74 if (ret)
75 return ret;
76
77 /* Power up usb phy analog blocks by set siddq 0 */
78 ret = rockchip_usb_phy_power(phy, 0);
79 if (ret) {
80 clk_disable_unprepare(phy->clk);
81 return ret;
82 }
83
84 return 0;
85 }
86
87 static const struct phy_ops ops = {
88 .power_on = rockchip_usb_phy_power_on,
89 .power_off = rockchip_usb_phy_power_off,
90 .owner = THIS_MODULE,
91 };
92
rockchip_usb_phy_probe(struct platform_device * pdev)93 static int rockchip_usb_phy_probe(struct platform_device *pdev)
94 {
95 struct device *dev = &pdev->dev;
96 struct rockchip_usb_phy *rk_phy;
97 struct phy_provider *phy_provider;
98 struct device_node *child;
99 struct regmap *grf;
100 unsigned int reg_offset;
101 int err;
102
103 grf = syscon_regmap_lookup_by_phandle(dev->of_node, "rockchip,grf");
104 if (IS_ERR(grf)) {
105 dev_err(&pdev->dev, "Missing rockchip,grf property\n");
106 return PTR_ERR(grf);
107 }
108
109 for_each_available_child_of_node(dev->of_node, child) {
110 rk_phy = devm_kzalloc(dev, sizeof(*rk_phy), GFP_KERNEL);
111 if (!rk_phy) {
112 err = -ENOMEM;
113 goto put_child;
114 }
115
116 if (of_property_read_u32(child, "reg", ®_offset)) {
117 dev_err(dev, "missing reg property in node %s\n",
118 child->name);
119 err = -EINVAL;
120 goto put_child;
121 }
122
123 rk_phy->reg_offset = reg_offset;
124 rk_phy->reg_base = grf;
125
126 rk_phy->clk = of_clk_get_by_name(child, "phyclk");
127 if (IS_ERR(rk_phy->clk))
128 rk_phy->clk = NULL;
129
130 rk_phy->phy = devm_phy_create(dev, child, &ops);
131 if (IS_ERR(rk_phy->phy)) {
132 dev_err(dev, "failed to create PHY\n");
133 err = PTR_ERR(rk_phy->phy);
134 goto put_child;
135 }
136 phy_set_drvdata(rk_phy->phy, rk_phy);
137
138 /* only power up usb phy when it use, so disable it when init*/
139 err = rockchip_usb_phy_power(rk_phy, 1);
140 if (err)
141 goto put_child;
142 }
143
144 phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
145 return PTR_ERR_OR_ZERO(phy_provider);
146 put_child:
147 of_node_put(child);
148 return err;
149 }
150
151 static const struct of_device_id rockchip_usb_phy_dt_ids[] = {
152 { .compatible = "rockchip,rk3288-usb-phy" },
153 {}
154 };
155
156 MODULE_DEVICE_TABLE(of, rockchip_usb_phy_dt_ids);
157
158 static struct platform_driver rockchip_usb_driver = {
159 .probe = rockchip_usb_phy_probe,
160 .driver = {
161 .name = "rockchip-usb-phy",
162 .of_match_table = rockchip_usb_phy_dt_ids,
163 },
164 };
165
166 module_platform_driver(rockchip_usb_driver);
167
168 MODULE_AUTHOR("Yunzhi Li <lyz@rock-chips.com>");
169 MODULE_DESCRIPTION("Rockchip USB 2.0 PHY driver");
170 MODULE_LICENSE("GPL v2");
171