xref: /openbmc/linux/drivers/usb/host/ohci-exynos.c (revision 7d545e77)
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 const char hcd_name[] = "ohci-exynos";
25 static struct hc_driver __read_mostly exynos_ohci_hc_driver;
26 
27 #define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv)
28 
29 #define PHY_NUMBER 3
30 
31 struct exynos_ohci_hcd {
32 	struct clk *clk;
33 	struct device_node *of_node;
34 	struct phy *phy[PHY_NUMBER];
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;
43 	int ret;
44 
45 	/* Get PHYs for the controller */
46 	for_each_available_child_of_node(dev->of_node, child) {
47 		ret = of_property_read_u32(child, "reg", &phy_number);
48 		if (ret) {
49 			dev_err(dev, "Failed to parse device tree\n");
50 			of_node_put(child);
51 			return ret;
52 		}
53 
54 		if (phy_number >= PHY_NUMBER) {
55 			dev_err(dev, "Invalid number of PHYs\n");
56 			of_node_put(child);
57 			return -EINVAL;
58 		}
59 
60 		phy = devm_of_phy_get(dev, child, NULL);
61 		exynos_ohci->phy[phy_number] = phy;
62 		if (IS_ERR(phy)) {
63 			ret = PTR_ERR(phy);
64 			if (ret == -EPROBE_DEFER) {
65 				of_node_put(child);
66 				return ret;
67 			} else if (ret != -ENOSYS && ret != -ENODEV) {
68 				dev_err(dev,
69 					"Error retrieving usb2 phy: %d\n", ret);
70 				of_node_put(child);
71 				return ret;
72 			}
73 		}
74 	}
75 
76 	return 0;
77 }
78 
79 static int exynos_ohci_phy_enable(struct device *dev)
80 {
81 	struct usb_hcd *hcd = dev_get_drvdata(dev);
82 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
83 	int i;
84 	int ret = 0;
85 
86 	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
87 		if (!IS_ERR(exynos_ohci->phy[i]))
88 			ret = phy_power_on(exynos_ohci->phy[i]);
89 	if (ret)
90 		for (i--; i >= 0; i--)
91 			if (!IS_ERR(exynos_ohci->phy[i]))
92 				phy_power_off(exynos_ohci->phy[i]);
93 
94 	return ret;
95 }
96 
97 static void exynos_ohci_phy_disable(struct device *dev)
98 {
99 	struct usb_hcd *hcd = dev_get_drvdata(dev);
100 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
101 	int i;
102 
103 	for (i = 0; i < PHY_NUMBER; i++)
104 		if (!IS_ERR(exynos_ohci->phy[i]))
105 			phy_power_off(exynos_ohci->phy[i]);
106 }
107 
108 static int exynos_ohci_probe(struct platform_device *pdev)
109 {
110 	struct exynos_ohci_hcd *exynos_ohci;
111 	struct usb_hcd *hcd;
112 	struct resource *res;
113 	int irq;
114 	int err;
115 
116 	/*
117 	 * Right now device-tree probed devices don't get dma_mask set.
118 	 * Since shared usb code relies on it, set it here for now.
119 	 * Once we move to full device tree support this will vanish off.
120 	 */
121 	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
122 	if (err)
123 		return err;
124 
125 	hcd = usb_create_hcd(&exynos_ohci_hc_driver,
126 				&pdev->dev, dev_name(&pdev->dev));
127 	if (!hcd) {
128 		dev_err(&pdev->dev, "Unable to create HCD\n");
129 		return -ENOMEM;
130 	}
131 
132 	exynos_ohci = to_exynos_ohci(hcd);
133 
134 	err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
135 	if (err)
136 		goto fail_clk;
137 
138 	exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
139 
140 	if (IS_ERR(exynos_ohci->clk)) {
141 		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
142 		err = PTR_ERR(exynos_ohci->clk);
143 		goto fail_clk;
144 	}
145 
146 	err = clk_prepare_enable(exynos_ohci->clk);
147 	if (err)
148 		goto fail_clk;
149 
150 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
151 	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
152 	if (IS_ERR(hcd->regs)) {
153 		err = PTR_ERR(hcd->regs);
154 		goto fail_io;
155 	}
156 	hcd->rsrc_start = res->start;
157 	hcd->rsrc_len = resource_size(res);
158 
159 	irq = platform_get_irq(pdev, 0);
160 	if (!irq) {
161 		dev_err(&pdev->dev, "Failed to get IRQ\n");
162 		err = -ENODEV;
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 Exynos
176 	 * OHCI port subnodes and generic USB device bindings
177 	 */
178 	exynos_ohci->of_node = pdev->dev.of_node;
179 	pdev->dev.of_node = NULL;
180 
181 	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
182 	if (err) {
183 		dev_err(&pdev->dev, "Failed to add USB HCD\n");
184 		goto fail_add_hcd;
185 	}
186 	device_wakeup_enable(hcd->self.controller);
187 	return 0;
188 
189 fail_add_hcd:
190 	exynos_ohci_phy_disable(&pdev->dev);
191 	pdev->dev.of_node = exynos_ohci->of_node;
192 fail_io:
193 	clk_disable_unprepare(exynos_ohci->clk);
194 fail_clk:
195 	usb_put_hcd(hcd);
196 	return err;
197 }
198 
199 static int exynos_ohci_remove(struct platform_device *pdev)
200 {
201 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
202 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
203 
204 	pdev->dev.of_node = exynos_ohci->of_node;
205 
206 	usb_remove_hcd(hcd);
207 
208 	exynos_ohci_phy_disable(&pdev->dev);
209 
210 	clk_disable_unprepare(exynos_ohci->clk);
211 
212 	usb_put_hcd(hcd);
213 
214 	return 0;
215 }
216 
217 static void exynos_ohci_shutdown(struct platform_device *pdev)
218 {
219 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
220 
221 	if (hcd->driver->shutdown)
222 		hcd->driver->shutdown(hcd);
223 }
224 
225 #ifdef CONFIG_PM
226 static int exynos_ohci_suspend(struct device *dev)
227 {
228 	struct usb_hcd *hcd = dev_get_drvdata(dev);
229 	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
230 	bool do_wakeup = device_may_wakeup(dev);
231 	int rc = ohci_suspend(hcd, do_wakeup);
232 
233 	if (rc)
234 		return rc;
235 
236 	exynos_ohci_phy_disable(dev);
237 
238 	clk_disable_unprepare(exynos_ohci->clk);
239 
240 	return 0;
241 }
242 
243 static int exynos_ohci_resume(struct device *dev)
244 {
245 	struct usb_hcd *hcd			= dev_get_drvdata(dev);
246 	struct exynos_ohci_hcd *exynos_ohci	= to_exynos_ohci(hcd);
247 	int ret;
248 
249 	clk_prepare_enable(exynos_ohci->clk);
250 
251 	ret = exynos_ohci_phy_enable(dev);
252 	if (ret) {
253 		dev_err(dev, "Failed to enable USB phy\n");
254 		clk_disable_unprepare(exynos_ohci->clk);
255 		return ret;
256 	}
257 
258 	ohci_resume(hcd, false);
259 
260 	return 0;
261 }
262 #else
263 #define exynos_ohci_suspend	NULL
264 #define exynos_ohci_resume	NULL
265 #endif
266 
267 static const struct ohci_driver_overrides exynos_overrides __initconst = {
268 	.extra_priv_size =	sizeof(struct exynos_ohci_hcd),
269 };
270 
271 static const struct dev_pm_ops exynos_ohci_pm_ops = {
272 	.suspend	= exynos_ohci_suspend,
273 	.resume		= exynos_ohci_resume,
274 };
275 
276 #ifdef CONFIG_OF
277 static const struct of_device_id exynos_ohci_match[] = {
278 	{ .compatible = "samsung,exynos4210-ohci" },
279 	{},
280 };
281 MODULE_DEVICE_TABLE(of, exynos_ohci_match);
282 #endif
283 
284 static struct platform_driver exynos_ohci_driver = {
285 	.probe		= exynos_ohci_probe,
286 	.remove		= exynos_ohci_remove,
287 	.shutdown	= exynos_ohci_shutdown,
288 	.driver = {
289 		.name	= "exynos-ohci",
290 		.pm	= &exynos_ohci_pm_ops,
291 		.of_match_table	= of_match_ptr(exynos_ohci_match),
292 	}
293 };
294 static int __init ohci_exynos_init(void)
295 {
296 	if (usb_disabled())
297 		return -ENODEV;
298 
299 	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
300 	ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
301 	return platform_driver_register(&exynos_ohci_driver);
302 }
303 module_init(ohci_exynos_init);
304 
305 static void __exit ohci_exynos_cleanup(void)
306 {
307 	platform_driver_unregister(&exynos_ohci_driver);
308 }
309 module_exit(ohci_exynos_cleanup);
310 
311 MODULE_ALIAS("platform:exynos-ohci");
312 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
313 MODULE_LICENSE("GPL v2");
314