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
exynos_ohci_get_phy(struct device * dev,struct exynos_ohci_hcd * exynos_ohci)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
exynos_ohci_phy_enable(struct device * dev)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
exynos_ohci_phy_disable(struct device * dev)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
exynos_ohci_probe(struct platform_device * pdev)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 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
153 hcd->regs = devm_ioremap_resource(&pdev->dev, res);
154 if (IS_ERR(hcd->regs)) {
155 err = PTR_ERR(hcd->regs);
156 goto fail_io;
157 }
158 hcd->rsrc_start = res->start;
159 hcd->rsrc_len = resource_size(res);
160
161 irq = platform_get_irq(pdev, 0);
162 if (irq < 0) {
163 err = irq;
164 goto fail_io;
165 }
166
167 platform_set_drvdata(pdev, hcd);
168
169 err = exynos_ohci_phy_enable(&pdev->dev);
170 if (err) {
171 dev_err(&pdev->dev, "Failed to enable USB phy\n");
172 goto fail_io;
173 }
174
175 /*
176 * Workaround: reset of_node pointer to avoid conflict between legacy
177 * Exynos OHCI port subnodes and generic USB device bindings
178 */
179 exynos_ohci->of_node = pdev->dev.of_node;
180 if (exynos_ohci->legacy_phy)
181 pdev->dev.of_node = NULL;
182
183 err = usb_add_hcd(hcd, irq, IRQF_SHARED);
184 if (err) {
185 dev_err(&pdev->dev, "Failed to add USB HCD\n");
186 goto fail_add_hcd;
187 }
188 device_wakeup_enable(hcd->self.controller);
189 return 0;
190
191 fail_add_hcd:
192 exynos_ohci_phy_disable(&pdev->dev);
193 pdev->dev.of_node = exynos_ohci->of_node;
194 fail_io:
195 clk_disable_unprepare(exynos_ohci->clk);
196 fail_clk:
197 usb_put_hcd(hcd);
198 return err;
199 }
200
exynos_ohci_remove(struct platform_device * pdev)201 static int exynos_ohci_remove(struct platform_device *pdev)
202 {
203 struct usb_hcd *hcd = platform_get_drvdata(pdev);
204 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
205
206 pdev->dev.of_node = exynos_ohci->of_node;
207
208 usb_remove_hcd(hcd);
209
210 exynos_ohci_phy_disable(&pdev->dev);
211
212 clk_disable_unprepare(exynos_ohci->clk);
213
214 usb_put_hcd(hcd);
215
216 return 0;
217 }
218
exynos_ohci_shutdown(struct platform_device * pdev)219 static void exynos_ohci_shutdown(struct platform_device *pdev)
220 {
221 struct usb_hcd *hcd = platform_get_drvdata(pdev);
222
223 if (hcd->driver->shutdown)
224 hcd->driver->shutdown(hcd);
225 }
226
227 #ifdef CONFIG_PM
exynos_ohci_suspend(struct device * dev)228 static int exynos_ohci_suspend(struct device *dev)
229 {
230 struct usb_hcd *hcd = dev_get_drvdata(dev);
231 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
232 bool do_wakeup = device_may_wakeup(dev);
233 int rc = ohci_suspend(hcd, do_wakeup);
234
235 if (rc)
236 return rc;
237
238 exynos_ohci_phy_disable(dev);
239
240 clk_disable_unprepare(exynos_ohci->clk);
241
242 return 0;
243 }
244
exynos_ohci_resume(struct device * dev)245 static int exynos_ohci_resume(struct device *dev)
246 {
247 struct usb_hcd *hcd = dev_get_drvdata(dev);
248 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
249 int ret;
250
251 clk_prepare_enable(exynos_ohci->clk);
252
253 ret = exynos_ohci_phy_enable(dev);
254 if (ret) {
255 dev_err(dev, "Failed to enable USB phy\n");
256 clk_disable_unprepare(exynos_ohci->clk);
257 return ret;
258 }
259
260 ohci_resume(hcd, false);
261
262 return 0;
263 }
264 #else
265 #define exynos_ohci_suspend NULL
266 #define exynos_ohci_resume NULL
267 #endif
268
269 static const struct ohci_driver_overrides exynos_overrides __initconst = {
270 .extra_priv_size = sizeof(struct exynos_ohci_hcd),
271 };
272
273 static const struct dev_pm_ops exynos_ohci_pm_ops = {
274 .suspend = exynos_ohci_suspend,
275 .resume = exynos_ohci_resume,
276 };
277
278 #ifdef CONFIG_OF
279 static const struct of_device_id exynos_ohci_match[] = {
280 { .compatible = "samsung,exynos4210-ohci" },
281 {},
282 };
283 MODULE_DEVICE_TABLE(of, exynos_ohci_match);
284 #endif
285
286 static struct platform_driver exynos_ohci_driver = {
287 .probe = exynos_ohci_probe,
288 .remove = exynos_ohci_remove,
289 .shutdown = exynos_ohci_shutdown,
290 .driver = {
291 .name = "exynos-ohci",
292 .pm = &exynos_ohci_pm_ops,
293 .of_match_table = of_match_ptr(exynos_ohci_match),
294 }
295 };
ohci_exynos_init(void)296 static int __init ohci_exynos_init(void)
297 {
298 if (usb_disabled())
299 return -ENODEV;
300
301 ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
302 return platform_driver_register(&exynos_ohci_driver);
303 }
304 module_init(ohci_exynos_init);
305
ohci_exynos_cleanup(void)306 static void __exit ohci_exynos_cleanup(void)
307 {
308 platform_driver_unregister(&exynos_ohci_driver);
309 }
310 module_exit(ohci_exynos_cleanup);
311
312 MODULE_ALIAS("platform:exynos-ohci");
313 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
314 MODULE_LICENSE("GPL v2");
315