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 */
36struct 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 */
50struct stih41x_usb_phy {
51	struct device *dev;
52	struct regmap *regmap;
53	const struct stih41x_usb_cfg *cfg;
54	struct clk *clk;
55};
56
57static struct stih41x_usb_cfg stih415_usb_phy_cfg = {
58	.syscfg = SYSCFG332,
59	.cfg_mask = 0x3f,
60	.cfg = 0x38,
61	.oscok = BIT(6),
62};
63
64static struct stih41x_usb_cfg stih416_usb_phy_cfg = {
65	.syscfg = SYSCFG2520,
66	.cfg_mask = 0x33f,
67	.cfg = 0x238,
68	.oscok = BIT(6),
69};
70
71static 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
79static 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
98static 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
115static 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
122static const struct of_device_id stih41x_usb_phy_of_match[];
123
124static 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
170static 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};
175MODULE_DEVICE_TABLE(of, stih41x_usb_phy_of_match);
176
177static 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};
184module_platform_driver(stih41x_usb_phy_driver);
185
186MODULE_AUTHOR("Maxime Coquelin <maxime.coquelin@st.com>");
187MODULE_DESCRIPTION("STMicroelectronics USB PHY driver for STiH41x series");
188MODULE_LICENSE("GPL v2");
189