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_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
exynos_ohci_phy_enable(struct device * dev)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
exynos_ohci_phy_disable(struct device * dev)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
exynos_ohci_probe(struct platform_device * pdev)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
exynos_ohci_remove(struct platform_device * pdev)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
exynos_ohci_shutdown(struct platform_device * pdev)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
exynos_ohci_suspend(struct device * dev)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
exynos_ohci_resume(struct device * dev)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 };
ohci_exynos_init(void)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
ohci_exynos_cleanup(void)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