xref: /openbmc/linux/drivers/usb/host/ohci-exynos.c (revision a325f174)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * SAMSUNG EXYNOS USB HOST OHCI Controller
4  *
5  * Copyright (C) 2011 Samsung Electronics Co.Ltd
6  * Author: Jingoo Han <jg1.han@samsung.com>
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/io.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/platform_device.h>
16 #include <linux/phy/phy.h>
17 #include <linux/usb.h>
18 #include <linux/usb/hcd.h>
19 
20 #include "ohci.h"
21 
22 #define DRIVER_DESC "OHCI Exynos driver"
23 
24 static struct hc_driver __read_mostly exynos_ohci_hc_driver;
25 
26 #define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv)
27 
28 #define PHY_NUMBER 3
29 
30 struct exynos_ohci_hcd {
31 	struct clk *clk;
32 	struct device_node *of_node;
33 	struct phy *phy[PHY_NUMBER];
34 	bool legacy_phy;
35 };
36 
37 static int exynos_ohci_get_phy(struct device *dev,
38 				struct exynos_ohci_hcd *exynos_ohci)
39 {
40 	struct device_node *child;
41 	struct phy *phy;
42 	int phy_number, num_phys;
43 	int ret;
44 
45 	/* Get PHYs for the controller */
46 	num_phys = of_count_phandle_with_args(dev->of_node, "phys",
47 					      "#phy-cells");
48 	for (phy_number = 0; phy_number < num_phys; phy_number++) {
49 		phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number);
50 		if (IS_ERR(phy))
51 			return PTR_ERR(phy);
52 		exynos_ohci->phy[phy_number] = phy;
53 	}
54 	if (num_phys > 0)
55 		return 0;
56 
57 	/* Get PHYs using legacy bindings */
58 	for_each_available_child_of_node(dev->of_node, child) {
59 		ret = of_property_read_u32(child, "reg", &phy_number);
60 		if (ret) {
61 			dev_err(dev, "Failed to parse device tree\n");
62 			of_node_put(child);
63 			return ret;
64 		}
65 
66 		if (phy_number >= PHY_NUMBER) {
67 			dev_err(dev, "Invalid number of PHYs\n");
68 			of_node_put(child);
69 			return -EINVAL;
70 		}
71 
72 		phy = devm_of_phy_optional_get(dev, child, NULL);
73 		exynos_ohci->phy[phy_number] = phy;
74 		if (IS_ERR(phy)) {
75 			of_node_put(child);
76 			return PTR_ERR(phy);
77 		}
78 	}
79 
80 	exynos_ohci->legacy_phy = true;
81 	return 0;
82 }
83 
84 static int exynos_ohci_phy_enable(struct device *dev)
85 {
86 	struct usb_hcd *hcd = dev_get_drvdata(dev);
87 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
88 	int i;
89 	int ret = 0;
90 
91 	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
92 		ret = phy_power_on(exynos_ohci->phy[i]);
93 	if (ret)
94 		for (i--; i >= 0; i--)
95 			phy_power_off(exynos_ohci->phy[i]);
96 
97 	return ret;
98 }
99 
100 static void exynos_ohci_phy_disable(struct device *dev)
101 {
102 	struct usb_hcd *hcd = dev_get_drvdata(dev);
103 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
104 	int i;
105 
106 	for (i = 0; i < PHY_NUMBER; i++)
107 		phy_power_off(exynos_ohci->phy[i]);
108 }
109 
110 static int exynos_ohci_probe(struct platform_device *pdev)
111 {
112 	struct exynos_ohci_hcd *exynos_ohci;
113 	struct usb_hcd *hcd;
114 	struct resource *res;
115 	int irq;
116 	int err;
117 
118 	/*
119 	 * Right now device-tree probed devices don't get dma_mask set.
120 	 * Since shared usb code relies on it, set it here for now.
121 	 * Once we move to full device tree support this will vanish off.
122 	 */
123 	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
124 	if (err)
125 		return err;
126 
127 	hcd = usb_create_hcd(&exynos_ohci_hc_driver,
128 				&pdev->dev, dev_name(&pdev->dev));
129 	if (!hcd) {
130 		dev_err(&pdev->dev, "Unable to create HCD\n");
131 		return -ENOMEM;
132 	}
133 
134 	exynos_ohci = to_exynos_ohci(hcd);
135 
136 	err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
137 	if (err)
138 		goto fail_clk;
139 
140 	exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
141 
142 	if (IS_ERR(exynos_ohci->clk)) {
143 		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
144 		err = PTR_ERR(exynos_ohci->clk);
145 		goto fail_clk;
146 	}
147 
148 	err = clk_prepare_enable(exynos_ohci->clk);
149 	if (err)
150 		goto fail_clk;
151 
152 	hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
153 	if (IS_ERR(hcd->regs)) {
154 		err = PTR_ERR(hcd->regs);
155 		goto fail_io;
156 	}
157 	hcd->rsrc_start = res->start;
158 	hcd->rsrc_len = resource_size(res);
159 
160 	irq = platform_get_irq(pdev, 0);
161 	if (irq < 0) {
162 		err = irq;
163 		goto fail_io;
164 	}
165 
166 	platform_set_drvdata(pdev, hcd);
167 
168 	err = exynos_ohci_phy_enable(&pdev->dev);
169 	if (err) {
170 		dev_err(&pdev->dev, "Failed to enable USB phy\n");
171 		goto fail_io;
172 	}
173 
174 	/*
175 	 * Workaround: reset of_node pointer to avoid conflict between legacy
176 	 * Exynos OHCI port subnodes and generic USB device bindings
177 	 */
178 	exynos_ohci->of_node = pdev->dev.of_node;
179 	if (exynos_ohci->legacy_phy)
180 		pdev->dev.of_node = NULL;
181 
182 	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
183 	if (err) {
184 		dev_err(&pdev->dev, "Failed to add USB HCD\n");
185 		goto fail_add_hcd;
186 	}
187 	device_wakeup_enable(hcd->self.controller);
188 	return 0;
189 
190 fail_add_hcd:
191 	exynos_ohci_phy_disable(&pdev->dev);
192 	pdev->dev.of_node = exynos_ohci->of_node;
193 fail_io:
194 	clk_disable_unprepare(exynos_ohci->clk);
195 fail_clk:
196 	usb_put_hcd(hcd);
197 	return err;
198 }
199 
200 static void exynos_ohci_remove(struct platform_device *pdev)
201 {
202 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
203 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
204 
205 	pdev->dev.of_node = exynos_ohci->of_node;
206 
207 	usb_remove_hcd(hcd);
208 
209 	exynos_ohci_phy_disable(&pdev->dev);
210 
211 	clk_disable_unprepare(exynos_ohci->clk);
212 
213 	usb_put_hcd(hcd);
214 }
215 
216 static void exynos_ohci_shutdown(struct platform_device *pdev)
217 {
218 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
219 
220 	if (hcd->driver->shutdown)
221 		hcd->driver->shutdown(hcd);
222 }
223 
224 #ifdef CONFIG_PM
225 static int exynos_ohci_suspend(struct device *dev)
226 {
227 	struct usb_hcd *hcd = dev_get_drvdata(dev);
228 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
229 	bool do_wakeup = device_may_wakeup(dev);
230 	int rc = ohci_suspend(hcd, do_wakeup);
231 
232 	if (rc)
233 		return rc;
234 
235 	exynos_ohci_phy_disable(dev);
236 
237 	clk_disable_unprepare(exynos_ohci->clk);
238 
239 	return 0;
240 }
241 
242 static int exynos_ohci_resume(struct device *dev)
243 {
244 	struct usb_hcd *hcd			= dev_get_drvdata(dev);
245 	struct exynos_ohci_hcd *exynos_ohci	= to_exynos_ohci(hcd);
246 	int ret;
247 
248 	clk_prepare_enable(exynos_ohci->clk);
249 
250 	ret = exynos_ohci_phy_enable(dev);
251 	if (ret) {
252 		dev_err(dev, "Failed to enable USB phy\n");
253 		clk_disable_unprepare(exynos_ohci->clk);
254 		return ret;
255 	}
256 
257 	ohci_resume(hcd, false);
258 
259 	return 0;
260 }
261 #else
262 #define exynos_ohci_suspend	NULL
263 #define exynos_ohci_resume	NULL
264 #endif
265 
266 static const struct ohci_driver_overrides exynos_overrides __initconst = {
267 	.extra_priv_size =	sizeof(struct exynos_ohci_hcd),
268 };
269 
270 static const struct dev_pm_ops exynos_ohci_pm_ops = {
271 	.suspend	= exynos_ohci_suspend,
272 	.resume		= exynos_ohci_resume,
273 };
274 
275 #ifdef CONFIG_OF
276 static const struct of_device_id exynos_ohci_match[] = {
277 	{ .compatible = "samsung,exynos4210-ohci" },
278 	{},
279 };
280 MODULE_DEVICE_TABLE(of, exynos_ohci_match);
281 #endif
282 
283 static struct platform_driver exynos_ohci_driver = {
284 	.probe		= exynos_ohci_probe,
285 	.remove_new	= exynos_ohci_remove,
286 	.shutdown	= exynos_ohci_shutdown,
287 	.driver = {
288 		.name	= "exynos-ohci",
289 		.pm	= &exynos_ohci_pm_ops,
290 		.of_match_table	= of_match_ptr(exynos_ohci_match),
291 	}
292 };
293 static int __init ohci_exynos_init(void)
294 {
295 	if (usb_disabled())
296 		return -ENODEV;
297 
298 	ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
299 	return platform_driver_register(&exynos_ohci_driver);
300 }
301 module_init(ohci_exynos_init);
302 
303 static void __exit ohci_exynos_cleanup(void)
304 {
305 	platform_driver_unregister(&exynos_ohci_driver);
306 }
307 module_exit(ohci_exynos_cleanup);
308 
309 MODULE_ALIAS("platform:exynos-ohci");
310 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
311 MODULE_LICENSE("GPL v2");
312