1 /*
2  * Samsung SoC USB 1.1/2.0 PHY driver
3  *
4  * Copyright (C) 2013 Samsung Electronics Co., Ltd.
5  * Author: Kamil Debski <k.debski@samsung.com>
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 version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/clk.h>
13 #include <linux/mfd/syscon.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_device.h>
18 #include <linux/phy/phy.h>
19 #include <linux/platform_device.h>
20 #include <linux/spinlock.h>
21 #include "phy-samsung-usb2.h"
22 
23 static int samsung_usb2_phy_power_on(struct phy *phy)
24 {
25 	struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
26 	struct samsung_usb2_phy_driver *drv = inst->drv;
27 	int ret;
28 
29 	dev_dbg(drv->dev, "Request to power_on \"%s\" usb phy\n",
30 		inst->cfg->label);
31 
32 	if (drv->vbus) {
33 		ret = regulator_enable(drv->vbus);
34 		if (ret)
35 			goto err_regulator;
36 	}
37 
38 	ret = clk_prepare_enable(drv->clk);
39 	if (ret)
40 		goto err_main_clk;
41 	ret = clk_prepare_enable(drv->ref_clk);
42 	if (ret)
43 		goto err_instance_clk;
44 	if (inst->cfg->power_on) {
45 		spin_lock(&drv->lock);
46 		ret = inst->cfg->power_on(inst);
47 		spin_unlock(&drv->lock);
48 		if (ret)
49 			goto err_power_on;
50 	}
51 
52 	return 0;
53 
54 err_power_on:
55 	clk_disable_unprepare(drv->ref_clk);
56 err_instance_clk:
57 	clk_disable_unprepare(drv->clk);
58 err_main_clk:
59 	if (drv->vbus)
60 		regulator_disable(drv->vbus);
61 err_regulator:
62 	return ret;
63 }
64 
65 static int samsung_usb2_phy_power_off(struct phy *phy)
66 {
67 	struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
68 	struct samsung_usb2_phy_driver *drv = inst->drv;
69 	int ret = 0;
70 
71 	dev_dbg(drv->dev, "Request to power_off \"%s\" usb phy\n",
72 		inst->cfg->label);
73 	if (inst->cfg->power_off) {
74 		spin_lock(&drv->lock);
75 		ret = inst->cfg->power_off(inst);
76 		spin_unlock(&drv->lock);
77 		if (ret)
78 			return ret;
79 	}
80 	clk_disable_unprepare(drv->ref_clk);
81 	clk_disable_unprepare(drv->clk);
82 	if (drv->vbus)
83 		ret = regulator_disable(drv->vbus);
84 
85 	return ret;
86 }
87 
88 static const struct phy_ops samsung_usb2_phy_ops = {
89 	.power_on	= samsung_usb2_phy_power_on,
90 	.power_off	= samsung_usb2_phy_power_off,
91 	.owner		= THIS_MODULE,
92 };
93 
94 static struct phy *samsung_usb2_phy_xlate(struct device *dev,
95 					struct of_phandle_args *args)
96 {
97 	struct samsung_usb2_phy_driver *drv;
98 
99 	drv = dev_get_drvdata(dev);
100 	if (!drv)
101 		return ERR_PTR(-EINVAL);
102 
103 	if (WARN_ON(args->args[0] >= drv->cfg->num_phys))
104 		return ERR_PTR(-ENODEV);
105 
106 	return drv->instances[args->args[0]].phy;
107 }
108 
109 static const struct of_device_id samsung_usb2_phy_of_match[] = {
110 #ifdef CONFIG_PHY_EXYNOS4X12_USB2
111 	{
112 		.compatible = "samsung,exynos3250-usb2-phy",
113 		.data = &exynos3250_usb2_phy_config,
114 	},
115 #endif
116 #ifdef CONFIG_PHY_EXYNOS4210_USB2
117 	{
118 		.compatible = "samsung,exynos4210-usb2-phy",
119 		.data = &exynos4210_usb2_phy_config,
120 	},
121 #endif
122 #ifdef CONFIG_PHY_EXYNOS4X12_USB2
123 	{
124 		.compatible = "samsung,exynos4x12-usb2-phy",
125 		.data = &exynos4x12_usb2_phy_config,
126 	},
127 #endif
128 #ifdef CONFIG_PHY_EXYNOS5250_USB2
129 	{
130 		.compatible = "samsung,exynos5250-usb2-phy",
131 		.data = &exynos5250_usb2_phy_config,
132 	},
133 #endif
134 #ifdef CONFIG_PHY_S5PV210_USB2
135 	{
136 		.compatible = "samsung,s5pv210-usb2-phy",
137 		.data = &s5pv210_usb2_phy_config,
138 	},
139 #endif
140 	{ },
141 };
142 MODULE_DEVICE_TABLE(of, samsung_usb2_phy_of_match);
143 
144 static int samsung_usb2_phy_probe(struct platform_device *pdev)
145 {
146 	const struct samsung_usb2_phy_config *cfg;
147 	struct device *dev = &pdev->dev;
148 	struct phy_provider *phy_provider;
149 	struct resource *mem;
150 	struct samsung_usb2_phy_driver *drv;
151 	int i, ret;
152 
153 	if (!pdev->dev.of_node) {
154 		dev_err(dev, "This driver is required to be instantiated from device tree\n");
155 		return -EINVAL;
156 	}
157 
158 	cfg = of_device_get_match_data(dev);
159 	if (!cfg)
160 		return -EINVAL;
161 
162 	drv = devm_kzalloc(dev, sizeof(struct samsung_usb2_phy_driver) +
163 		cfg->num_phys * sizeof(struct samsung_usb2_phy_instance),
164 								GFP_KERNEL);
165 	if (!drv)
166 		return -ENOMEM;
167 
168 	dev_set_drvdata(dev, drv);
169 	spin_lock_init(&drv->lock);
170 
171 	drv->cfg = cfg;
172 	drv->dev = dev;
173 
174 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
175 	drv->reg_phy = devm_ioremap_resource(dev, mem);
176 	if (IS_ERR(drv->reg_phy)) {
177 		dev_err(dev, "Failed to map register memory (phy)\n");
178 		return PTR_ERR(drv->reg_phy);
179 	}
180 
181 	drv->reg_pmu = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
182 		"samsung,pmureg-phandle");
183 	if (IS_ERR(drv->reg_pmu)) {
184 		dev_err(dev, "Failed to map PMU registers (via syscon)\n");
185 		return PTR_ERR(drv->reg_pmu);
186 	}
187 
188 	if (drv->cfg->has_mode_switch) {
189 		drv->reg_sys = syscon_regmap_lookup_by_phandle(
190 				pdev->dev.of_node, "samsung,sysreg-phandle");
191 		if (IS_ERR(drv->reg_sys)) {
192 			dev_err(dev, "Failed to map system registers (via syscon)\n");
193 			return PTR_ERR(drv->reg_sys);
194 		}
195 	}
196 
197 	drv->clk = devm_clk_get(dev, "phy");
198 	if (IS_ERR(drv->clk)) {
199 		dev_err(dev, "Failed to get clock of phy controller\n");
200 		return PTR_ERR(drv->clk);
201 	}
202 
203 	drv->ref_clk = devm_clk_get(dev, "ref");
204 	if (IS_ERR(drv->ref_clk)) {
205 		dev_err(dev, "Failed to get reference clock for the phy controller\n");
206 		return PTR_ERR(drv->ref_clk);
207 	}
208 
209 	drv->ref_rate = clk_get_rate(drv->ref_clk);
210 	if (drv->cfg->rate_to_clk) {
211 		ret = drv->cfg->rate_to_clk(drv->ref_rate, &drv->ref_reg_val);
212 		if (ret)
213 			return ret;
214 	}
215 
216 	drv->vbus = devm_regulator_get(dev, "vbus");
217 	if (IS_ERR(drv->vbus)) {
218 		ret = PTR_ERR(drv->vbus);
219 		if (ret == -EPROBE_DEFER)
220 			return ret;
221 		drv->vbus = NULL;
222 	}
223 
224 	for (i = 0; i < drv->cfg->num_phys; i++) {
225 		char *label = drv->cfg->phys[i].label;
226 		struct samsung_usb2_phy_instance *p = &drv->instances[i];
227 
228 		dev_dbg(dev, "Creating phy \"%s\"\n", label);
229 		p->phy = devm_phy_create(dev, NULL, &samsung_usb2_phy_ops);
230 		if (IS_ERR(p->phy)) {
231 			dev_err(drv->dev, "Failed to create usb2_phy \"%s\"\n",
232 				label);
233 			return PTR_ERR(p->phy);
234 		}
235 
236 		p->cfg = &drv->cfg->phys[i];
237 		p->drv = drv;
238 		phy_set_bus_width(p->phy, 8);
239 		phy_set_drvdata(p->phy, p);
240 	}
241 
242 	phy_provider = devm_of_phy_provider_register(dev,
243 							samsung_usb2_phy_xlate);
244 	if (IS_ERR(phy_provider)) {
245 		dev_err(drv->dev, "Failed to register phy provider\n");
246 		return PTR_ERR(phy_provider);
247 	}
248 
249 	return 0;
250 }
251 
252 static struct platform_driver samsung_usb2_phy_driver = {
253 	.probe	= samsung_usb2_phy_probe,
254 	.driver = {
255 		.of_match_table	= samsung_usb2_phy_of_match,
256 		.name		= "samsung-usb2-phy",
257 	}
258 };
259 
260 module_platform_driver(samsung_usb2_phy_driver);
261 MODULE_DESCRIPTION("Samsung S5P/EXYNOS SoC USB PHY driver");
262 MODULE_AUTHOR("Kamil Debski <k.debski@samsung.com>");
263 MODULE_LICENSE("GPL v2");
264 MODULE_ALIAS("platform:samsung-usb2-phy");
265