xref: /openbmc/linux/drivers/usb/host/ohci-exynos.c (revision f59a3ee6)
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_get(dev, child, NULL);
73 		exynos_ohci->phy[phy_number] = phy;
74 		if (IS_ERR(phy)) {
75 			ret = PTR_ERR(phy);
76 			if (ret == -EPROBE_DEFER) {
77 				of_node_put(child);
78 				return ret;
79 			} else if (ret != -ENOSYS && ret != -ENODEV) {
80 				dev_err(dev,
81 					"Error retrieving usb2 phy: %d\n", ret);
82 				of_node_put(child);
83 				return ret;
84 			}
85 		}
86 	}
87 
88 	exynos_ohci->legacy_phy = true;
89 	return 0;
90 }
91 
92 static int exynos_ohci_phy_enable(struct device *dev)
93 {
94 	struct usb_hcd *hcd = dev_get_drvdata(dev);
95 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
96 	int i;
97 	int ret = 0;
98 
99 	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
100 		if (!IS_ERR(exynos_ohci->phy[i]))
101 			ret = phy_power_on(exynos_ohci->phy[i]);
102 	if (ret)
103 		for (i--; i >= 0; i--)
104 			if (!IS_ERR(exynos_ohci->phy[i]))
105 				phy_power_off(exynos_ohci->phy[i]);
106 
107 	return ret;
108 }
109 
110 static void exynos_ohci_phy_disable(struct device *dev)
111 {
112 	struct usb_hcd *hcd = dev_get_drvdata(dev);
113 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
114 	int i;
115 
116 	for (i = 0; i < PHY_NUMBER; i++)
117 		if (!IS_ERR(exynos_ohci->phy[i]))
118 			phy_power_off(exynos_ohci->phy[i]);
119 }
120 
121 static int exynos_ohci_probe(struct platform_device *pdev)
122 {
123 	struct exynos_ohci_hcd *exynos_ohci;
124 	struct usb_hcd *hcd;
125 	struct resource *res;
126 	int irq;
127 	int err;
128 
129 	/*
130 	 * Right now device-tree probed devices don't get dma_mask set.
131 	 * Since shared usb code relies on it, set it here for now.
132 	 * Once we move to full device tree support this will vanish off.
133 	 */
134 	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
135 	if (err)
136 		return err;
137 
138 	hcd = usb_create_hcd(&exynos_ohci_hc_driver,
139 				&pdev->dev, dev_name(&pdev->dev));
140 	if (!hcd) {
141 		dev_err(&pdev->dev, "Unable to create HCD\n");
142 		return -ENOMEM;
143 	}
144 
145 	exynos_ohci = to_exynos_ohci(hcd);
146 
147 	err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
148 	if (err)
149 		goto fail_clk;
150 
151 	exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
152 
153 	if (IS_ERR(exynos_ohci->clk)) {
154 		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
155 		err = PTR_ERR(exynos_ohci->clk);
156 		goto fail_clk;
157 	}
158 
159 	err = clk_prepare_enable(exynos_ohci->clk);
160 	if (err)
161 		goto fail_clk;
162 
163 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
164 	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
165 	if (IS_ERR(hcd->regs)) {
166 		err = PTR_ERR(hcd->regs);
167 		goto fail_io;
168 	}
169 	hcd->rsrc_start = res->start;
170 	hcd->rsrc_len = resource_size(res);
171 
172 	irq = platform_get_irq(pdev, 0);
173 	if (irq < 0) {
174 		err = irq;
175 		goto fail_io;
176 	}
177 
178 	platform_set_drvdata(pdev, hcd);
179 
180 	err = exynos_ohci_phy_enable(&pdev->dev);
181 	if (err) {
182 		dev_err(&pdev->dev, "Failed to enable USB phy\n");
183 		goto fail_io;
184 	}
185 
186 	/*
187 	 * Workaround: reset of_node pointer to avoid conflict between legacy
188 	 * Exynos OHCI port subnodes and generic USB device bindings
189 	 */
190 	exynos_ohci->of_node = pdev->dev.of_node;
191 	if (exynos_ohci->legacy_phy)
192 		pdev->dev.of_node = NULL;
193 
194 	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
195 	if (err) {
196 		dev_err(&pdev->dev, "Failed to add USB HCD\n");
197 		goto fail_add_hcd;
198 	}
199 	device_wakeup_enable(hcd->self.controller);
200 	return 0;
201 
202 fail_add_hcd:
203 	exynos_ohci_phy_disable(&pdev->dev);
204 	pdev->dev.of_node = exynos_ohci->of_node;
205 fail_io:
206 	clk_disable_unprepare(exynos_ohci->clk);
207 fail_clk:
208 	usb_put_hcd(hcd);
209 	return err;
210 }
211 
212 static int exynos_ohci_remove(struct platform_device *pdev)
213 {
214 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
215 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
216 
217 	pdev->dev.of_node = exynos_ohci->of_node;
218 
219 	usb_remove_hcd(hcd);
220 
221 	exynos_ohci_phy_disable(&pdev->dev);
222 
223 	clk_disable_unprepare(exynos_ohci->clk);
224 
225 	usb_put_hcd(hcd);
226 
227 	return 0;
228 }
229 
230 static void exynos_ohci_shutdown(struct platform_device *pdev)
231 {
232 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
233 
234 	if (hcd->driver->shutdown)
235 		hcd->driver->shutdown(hcd);
236 }
237 
238 #ifdef CONFIG_PM
239 static int exynos_ohci_suspend(struct device *dev)
240 {
241 	struct usb_hcd *hcd = dev_get_drvdata(dev);
242 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
243 	bool do_wakeup = device_may_wakeup(dev);
244 	int rc = ohci_suspend(hcd, do_wakeup);
245 
246 	if (rc)
247 		return rc;
248 
249 	exynos_ohci_phy_disable(dev);
250 
251 	clk_disable_unprepare(exynos_ohci->clk);
252 
253 	return 0;
254 }
255 
256 static int exynos_ohci_resume(struct device *dev)
257 {
258 	struct usb_hcd *hcd			= dev_get_drvdata(dev);
259 	struct exynos_ohci_hcd *exynos_ohci	= to_exynos_ohci(hcd);
260 	int ret;
261 
262 	clk_prepare_enable(exynos_ohci->clk);
263 
264 	ret = exynos_ohci_phy_enable(dev);
265 	if (ret) {
266 		dev_err(dev, "Failed to enable USB phy\n");
267 		clk_disable_unprepare(exynos_ohci->clk);
268 		return ret;
269 	}
270 
271 	ohci_resume(hcd, false);
272 
273 	return 0;
274 }
275 #else
276 #define exynos_ohci_suspend	NULL
277 #define exynos_ohci_resume	NULL
278 #endif
279 
280 static const struct ohci_driver_overrides exynos_overrides __initconst = {
281 	.extra_priv_size =	sizeof(struct exynos_ohci_hcd),
282 };
283 
284 static const struct dev_pm_ops exynos_ohci_pm_ops = {
285 	.suspend	= exynos_ohci_suspend,
286 	.resume		= exynos_ohci_resume,
287 };
288 
289 #ifdef CONFIG_OF
290 static const struct of_device_id exynos_ohci_match[] = {
291 	{ .compatible = "samsung,exynos4210-ohci" },
292 	{},
293 };
294 MODULE_DEVICE_TABLE(of, exynos_ohci_match);
295 #endif
296 
297 static struct platform_driver exynos_ohci_driver = {
298 	.probe		= exynos_ohci_probe,
299 	.remove		= exynos_ohci_remove,
300 	.shutdown	= exynos_ohci_shutdown,
301 	.driver = {
302 		.name	= "exynos-ohci",
303 		.pm	= &exynos_ohci_pm_ops,
304 		.of_match_table	= of_match_ptr(exynos_ohci_match),
305 	}
306 };
307 static int __init ohci_exynos_init(void)
308 {
309 	if (usb_disabled())
310 		return -ENODEV;
311 
312 	ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
313 	return platform_driver_register(&exynos_ohci_driver);
314 }
315 module_init(ohci_exynos_init);
316 
317 static void __exit ohci_exynos_cleanup(void)
318 {
319 	platform_driver_unregister(&exynos_ohci_driver);
320 }
321 module_exit(ohci_exynos_cleanup);
322 
323 MODULE_ALIAS("platform:exynos-ohci");
324 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
325 MODULE_LICENSE("GPL v2");
326