GNU Linux-libre 4.4.289-gnu1
[releases.git] / drivers / phy / phy-rockchip-usb.c
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
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
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
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
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", &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");