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/phy/phy.h>
18 #include <linux/platform_device.h>
19 #include <linux/spinlock.h>
20 #include "phy-samsung-usb2.h"
21 
22 static int samsung_usb2_phy_power_on(struct phy *phy)
23 {
24 	struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
25 	struct samsung_usb2_phy_driver *drv = inst->drv;
26 	int ret;
27 
28 	dev_dbg(drv->dev, "Request to power_on \"%s\" usb phy\n",
29 		inst->cfg->label);
30 
31 	if (drv->vbus) {
32 		ret = regulator_enable(drv->vbus);
33 		if (ret)
34 			goto err_regulator;
35 	}
36 
37 	ret = clk_prepare_enable(drv->clk);
38 	if (ret)
39 		goto err_main_clk;
40 	ret = clk_prepare_enable(drv->ref_clk);
41 	if (ret)
42 		goto err_instance_clk;
43 	if (inst->cfg->power_on) {
44 		spin_lock(&drv->lock);
45 		ret = inst->cfg->power_on(inst);
46 		spin_unlock(&drv->lock);
47 		if (ret)
48 			goto err_power_on;
49 	}
50 
51 	return 0;
52 
53 err_power_on:
54 	clk_disable_unprepare(drv->ref_clk);
55 err_instance_clk:
56 	clk_disable_unprepare(drv->clk);
57 err_main_clk:
58 	if (drv->vbus)
59 		regulator_disable(drv->vbus);
60 err_regulator:
61 	return ret;
62 }
63 
64 static int samsung_usb2_phy_power_off(struct phy *phy)
65 {
66 	struct samsung_usb2_phy_instance *inst = phy_get_drvdata(phy);
67 	struct samsung_usb2_phy_driver *drv = inst->drv;
68 	int ret = 0;
69 
70 	dev_dbg(drv->dev, "Request to power_off \"%s\" usb phy\n",
71 		inst->cfg->label);
72 	if (inst->cfg->power_off) {
73 		spin_lock(&drv->lock);
74 		ret = inst->cfg->power_off(inst);
75 		spin_unlock(&drv->lock);
76 		if (ret)
77 			return ret;
78 	}
79 	clk_disable_unprepare(drv->ref_clk);
80 	clk_disable_unprepare(drv->clk);
81 	if (drv->vbus)
82 		ret = regulator_disable(drv->vbus);
83 
84 	return ret;
85 }
86 
87 static const struct phy_ops samsung_usb2_phy_ops = {
88 	.power_on	= samsung_usb2_phy_power_on,
89 	.power_off	= samsung_usb2_phy_power_off,
90 	.owner		= THIS_MODULE,
91 };
92 
93 static struct phy *samsung_usb2_phy_xlate(struct device *dev,
94 					struct of_phandle_args *args)
95 {
96 	struct samsung_usb2_phy_driver *drv;
97 
98 	drv = dev_get_drvdata(dev);
99 	if (!drv)
100 		return ERR_PTR(-EINVAL);
101 
102 	if (WARN_ON(args->args[0] >= drv->cfg->num_phys))
103 		return ERR_PTR(-ENODEV);
104 
105 	return drv->instances[args->args[0]].phy;
106 }
107 
108 static const struct of_device_id samsung_usb2_phy_of_match[] = {
109 #ifdef CONFIG_PHY_EXYNOS4X12_USB2
110 	{
111 		.compatible = "samsung,exynos3250-usb2-phy",
112 		.data = &exynos3250_usb2_phy_config,
113 	},
114 #endif
115 #ifdef CONFIG_PHY_EXYNOS4210_USB2
116 	{
117 		.compatible = "samsung,exynos4210-usb2-phy",
118 		.data = &exynos4210_usb2_phy_config,
119 	},
120 #endif
121 #ifdef CONFIG_PHY_EXYNOS4X12_USB2
122 	{
123 		.compatible = "samsung,exynos4x12-usb2-phy",
124 		.data = &exynos4x12_usb2_phy_config,
125 	},
126 #endif
127 #ifdef CONFIG_PHY_EXYNOS5250_USB2
128 	{
129 		.compatible = "samsung,exynos5250-usb2-phy",
130 		.data = &exynos5250_usb2_phy_config,
131 	},
132 #endif
133 #ifdef CONFIG_PHY_S5PV210_USB2
134 	{
135 		.compatible = "samsung,s5pv210-usb2-phy",
136 		.data = &s5pv210_usb2_phy_config,
137 	},
138 #endif
139 	{ },
140 };
141 MODULE_DEVICE_TABLE(of, samsung_usb2_phy_of_match);
142 
143 static int samsung_usb2_phy_probe(struct platform_device *pdev)
144 {
145 	const struct of_device_id *match;
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 	match = of_match_node(samsung_usb2_phy_of_match, pdev->dev.of_node);
159 	if (!match) {
160 		dev_err(dev, "of_match_node() failed\n");
161 		return -EINVAL;
162 	}
163 	cfg = match->data;
164 
165 	drv = devm_kzalloc(dev, sizeof(struct samsung_usb2_phy_driver) +
166 		cfg->num_phys * sizeof(struct samsung_usb2_phy_instance),
167 								GFP_KERNEL);
168 	if (!drv)
169 		return -ENOMEM;
170 
171 	dev_set_drvdata(dev, drv);
172 	spin_lock_init(&drv->lock);
173 
174 	drv->cfg = cfg;
175 	drv->dev = dev;
176 
177 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
178 	drv->reg_phy = devm_ioremap_resource(dev, mem);
179 	if (IS_ERR(drv->reg_phy)) {
180 		dev_err(dev, "Failed to map register memory (phy)\n");
181 		return PTR_ERR(drv->reg_phy);
182 	}
183 
184 	drv->reg_pmu = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
185 		"samsung,pmureg-phandle");
186 	if (IS_ERR(drv->reg_pmu)) {
187 		dev_err(dev, "Failed to map PMU registers (via syscon)\n");
188 		return PTR_ERR(drv->reg_pmu);
189 	}
190 
191 	if (drv->cfg->has_mode_switch) {
192 		drv->reg_sys = syscon_regmap_lookup_by_phandle(
193 				pdev->dev.of_node, "samsung,sysreg-phandle");
194 		if (IS_ERR(drv->reg_sys)) {
195 			dev_err(dev, "Failed to map system registers (via syscon)\n");
196 			return PTR_ERR(drv->reg_sys);
197 		}
198 	}
199 
200 	drv->clk = devm_clk_get(dev, "phy");
201 	if (IS_ERR(drv->clk)) {
202 		dev_err(dev, "Failed to get clock of phy controller\n");
203 		return PTR_ERR(drv->clk);
204 	}
205 
206 	drv->ref_clk = devm_clk_get(dev, "ref");
207 	if (IS_ERR(drv->ref_clk)) {
208 		dev_err(dev, "Failed to get reference clock for the phy controller\n");
209 		return PTR_ERR(drv->ref_clk);
210 	}
211 
212 	drv->ref_rate = clk_get_rate(drv->ref_clk);
213 	if (drv->cfg->rate_to_clk) {
214 		ret = drv->cfg->rate_to_clk(drv->ref_rate, &drv->ref_reg_val);
215 		if (ret)
216 			return ret;
217 	}
218 
219 	drv->vbus = devm_regulator_get(dev, "vbus");
220 	if (IS_ERR(drv->vbus)) {
221 		ret = PTR_ERR(drv->vbus);
222 		if (ret == -EPROBE_DEFER)
223 			return ret;
224 		drv->vbus = NULL;
225 	}
226 
227 	for (i = 0; i < drv->cfg->num_phys; i++) {
228 		char *label = drv->cfg->phys[i].label;
229 		struct samsung_usb2_phy_instance *p = &drv->instances[i];
230 
231 		dev_dbg(dev, "Creating phy \"%s\"\n", label);
232 		p->phy = devm_phy_create(dev, NULL, &samsung_usb2_phy_ops);
233 		if (IS_ERR(p->phy)) {
234 			dev_err(drv->dev, "Failed to create usb2_phy \"%s\"\n",
235 				label);
236 			return PTR_ERR(p->phy);
237 		}
238 
239 		p->cfg = &drv->cfg->phys[i];
240 		p->drv = drv;
241 		phy_set_bus_width(p->phy, 8);
242 		phy_set_drvdata(p->phy, p);
243 	}
244 
245 	phy_provider = devm_of_phy_provider_register(dev,
246 							samsung_usb2_phy_xlate);
247 	if (IS_ERR(phy_provider)) {
248 		dev_err(drv->dev, "Failed to register phy provider\n");
249 		return PTR_ERR(phy_provider);
250 	}
251 
252 	return 0;
253 }
254 
255 static struct platform_driver samsung_usb2_phy_driver = {
256 	.probe	= samsung_usb2_phy_probe,
257 	.driver = {
258 		.of_match_table	= samsung_usb2_phy_of_match,
259 		.name		= "samsung-usb2-phy",
260 	}
261 };
262 
263 module_platform_driver(samsung_usb2_phy_driver);
264 MODULE_DESCRIPTION("Samsung S5P/EXYNOS SoC USB PHY driver");
265 MODULE_AUTHOR("Kamil Debski <k.debski@samsung.com>");
266 MODULE_LICENSE("GPL v2");
267 MODULE_ALIAS("platform:samsung-usb2-phy");
268