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 bool legacy_phy;
36 };
37
exynos_ohci_get_phy(struct device * dev,struct exynos_ohci_hcd * exynos_ohci)38 static int exynos_ohci_get_phy(struct device *dev,
39 struct exynos_ohci_hcd *exynos_ohci)
40 {
41 struct device_node *child;
42 struct phy *phy;
43 int phy_number, num_phys;
44 int ret;
45
46 /* Get PHYs for the controller */
47 num_phys = of_count_phandle_with_args(dev->of_node, "phys",
48 "#phy-cells");
49 for (phy_number = 0; phy_number < num_phys; phy_number++) {
50 phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number);
51 if (IS_ERR(phy))
52 return PTR_ERR(phy);
53 exynos_ohci->phy[phy_number] = phy;
54 }
55 if (num_phys > 0)
56 return 0;
57
58 /* Get PHYs using legacy bindings */
59 for_each_available_child_of_node(dev->of_node, child) {
60 ret = of_property_read_u32(child, "reg", &phy_number);
61 if (ret) {
62 dev_err(dev, "Failed to parse device tree\n");
63 of_node_put(child);
64 return ret;
65 }
66
67 if (phy_number >= PHY_NUMBER) {
68 dev_err(dev, "Invalid number of PHYs\n");
69 of_node_put(child);
70 return -EINVAL;
71 }
72
73 phy = devm_of_phy_get(dev, child, NULL);
74 exynos_ohci->phy[phy_number] = phy;
75 if (IS_ERR(phy)) {
76 ret = PTR_ERR(phy);
77 if (ret == -EPROBE_DEFER) {
78 of_node_put(child);
79 return ret;
80 } else if (ret != -ENOSYS && ret != -ENODEV) {
81 dev_err(dev,
82 "Error retrieving usb2 phy: %d\n", ret);
83 of_node_put(child);
84 return ret;
85 }
86 }
87 }
88
89 exynos_ohci->legacy_phy = true;
90 return 0;
91 }
92
exynos_ohci_phy_enable(struct device * dev)93 static int exynos_ohci_phy_enable(struct device *dev)
94 {
95 struct usb_hcd *hcd = dev_get_drvdata(dev);
96 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
97 int i;
98 int ret = 0;
99
100 for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
101 if (!IS_ERR(exynos_ohci->phy[i]))
102 ret = phy_power_on(exynos_ohci->phy[i]);
103 if (ret)
104 for (i--; i >= 0; i--)
105 if (!IS_ERR(exynos_ohci->phy[i]))
106 phy_power_off(exynos_ohci->phy[i]);
107
108 return ret;
109 }
110
exynos_ohci_phy_disable(struct device * dev)111 static void exynos_ohci_phy_disable(struct device *dev)
112 {
113 struct usb_hcd *hcd = dev_get_drvdata(dev);
114 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
115 int i;
116
117 for (i = 0; i < PHY_NUMBER; i++)
118 if (!IS_ERR(exynos_ohci->phy[i]))
119 phy_power_off(exynos_ohci->phy[i]);
120 }
121
exynos_ohci_probe(struct platform_device * pdev)122 static int exynos_ohci_probe(struct platform_device *pdev)
123 {
124 struct exynos_ohci_hcd *exynos_ohci;
125 struct usb_hcd *hcd;
126 struct resource *res;
127 int irq;
128 int err;
129
130 /*
131 * Right now device-tree probed devices don't get dma_mask set.
132 * Since shared usb code relies on it, set it here for now.
133 * Once we move to full device tree support this will vanish off.
134 */
135 err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
136 if (err)
137 return err;
138
139 hcd = usb_create_hcd(&exynos_ohci_hc_driver,
140 &pdev->dev, dev_name(&pdev->dev));
141 if (!hcd) {
142 dev_err(&pdev->dev, "Unable to create HCD\n");
143 return -ENOMEM;
144 }
145
146 exynos_ohci = to_exynos_ohci(hcd);
147
148 err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
149 if (err)
150 goto fail_clk;
151
152 exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
153
154 if (IS_ERR(exynos_ohci->clk)) {
155 dev_err(&pdev->dev, "Failed to get usbhost clock\n");
156 err = PTR_ERR(exynos_ohci->clk);
157 goto fail_clk;
158 }
159
160 err = clk_prepare_enable(exynos_ohci->clk);
161 if (err)
162 goto fail_clk;
163
164 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
165 hcd->regs = devm_ioremap_resource(&pdev->dev, res);
166 if (IS_ERR(hcd->regs)) {
167 err = PTR_ERR(hcd->regs);
168 goto fail_io;
169 }
170 hcd->rsrc_start = res->start;
171 hcd->rsrc_len = resource_size(res);
172
173 irq = platform_get_irq(pdev, 0);
174 if (irq < 0) {
175 err = irq;
176 goto fail_io;
177 }
178
179 platform_set_drvdata(pdev, hcd);
180
181 err = exynos_ohci_phy_enable(&pdev->dev);
182 if (err) {
183 dev_err(&pdev->dev, "Failed to enable USB phy\n");
184 goto fail_io;
185 }
186
187 /*
188 * Workaround: reset of_node pointer to avoid conflict between legacy
189 * Exynos OHCI port subnodes and generic USB device bindings
190 */
191 exynos_ohci->of_node = pdev->dev.of_node;
192 if (exynos_ohci->legacy_phy)
193 pdev->dev.of_node = NULL;
194
195 err = usb_add_hcd(hcd, irq, IRQF_SHARED);
196 if (err) {
197 dev_err(&pdev->dev, "Failed to add USB HCD\n");
198 goto fail_add_hcd;
199 }
200 device_wakeup_enable(hcd->self.controller);
201 return 0;
202
203 fail_add_hcd:
204 exynos_ohci_phy_disable(&pdev->dev);
205 pdev->dev.of_node = exynos_ohci->of_node;
206 fail_io:
207 clk_disable_unprepare(exynos_ohci->clk);
208 fail_clk:
209 usb_put_hcd(hcd);
210 return err;
211 }
212
exynos_ohci_remove(struct platform_device * pdev)213 static int exynos_ohci_remove(struct platform_device *pdev)
214 {
215 struct usb_hcd *hcd = platform_get_drvdata(pdev);
216 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
217
218 pdev->dev.of_node = exynos_ohci->of_node;
219
220 usb_remove_hcd(hcd);
221
222 exynos_ohci_phy_disable(&pdev->dev);
223
224 clk_disable_unprepare(exynos_ohci->clk);
225
226 usb_put_hcd(hcd);
227
228 return 0;
229 }
230
exynos_ohci_shutdown(struct platform_device * pdev)231 static void exynos_ohci_shutdown(struct platform_device *pdev)
232 {
233 struct usb_hcd *hcd = platform_get_drvdata(pdev);
234
235 if (hcd->driver->shutdown)
236 hcd->driver->shutdown(hcd);
237 }
238
239 #ifdef CONFIG_PM
exynos_ohci_suspend(struct device * dev)240 static int exynos_ohci_suspend(struct device *dev)
241 {
242 struct usb_hcd *hcd = dev_get_drvdata(dev);
243 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
244 bool do_wakeup = device_may_wakeup(dev);
245 int rc = ohci_suspend(hcd, do_wakeup);
246
247 if (rc)
248 return rc;
249
250 exynos_ohci_phy_disable(dev);
251
252 clk_disable_unprepare(exynos_ohci->clk);
253
254 return 0;
255 }
256
exynos_ohci_resume(struct device * dev)257 static int exynos_ohci_resume(struct device *dev)
258 {
259 struct usb_hcd *hcd = dev_get_drvdata(dev);
260 struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
261 int ret;
262
263 clk_prepare_enable(exynos_ohci->clk);
264
265 ret = exynos_ohci_phy_enable(dev);
266 if (ret) {
267 dev_err(dev, "Failed to enable USB phy\n");
268 clk_disable_unprepare(exynos_ohci->clk);
269 return ret;
270 }
271
272 ohci_resume(hcd, false);
273
274 return 0;
275 }
276 #else
277 #define exynos_ohci_suspend NULL
278 #define exynos_ohci_resume NULL
279 #endif
280
281 static const struct ohci_driver_overrides exynos_overrides __initconst = {
282 .extra_priv_size = sizeof(struct exynos_ohci_hcd),
283 };
284
285 static const struct dev_pm_ops exynos_ohci_pm_ops = {
286 .suspend = exynos_ohci_suspend,
287 .resume = exynos_ohci_resume,
288 };
289
290 #ifdef CONFIG_OF
291 static const struct of_device_id exynos_ohci_match[] = {
292 { .compatible = "samsung,exynos4210-ohci" },
293 {},
294 };
295 MODULE_DEVICE_TABLE(of, exynos_ohci_match);
296 #endif
297
298 static struct platform_driver exynos_ohci_driver = {
299 .probe = exynos_ohci_probe,
300 .remove = exynos_ohci_remove,
301 .shutdown = exynos_ohci_shutdown,
302 .driver = {
303 .name = "exynos-ohci",
304 .pm = &exynos_ohci_pm_ops,
305 .of_match_table = of_match_ptr(exynos_ohci_match),
306 }
307 };
ohci_exynos_init(void)308 static int __init ohci_exynos_init(void)
309 {
310 if (usb_disabled())
311 return -ENODEV;
312
313 pr_info("%s: " DRIVER_DESC "\n", hcd_name);
314 ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
315 return platform_driver_register(&exynos_ohci_driver);
316 }
317 module_init(ohci_exynos_init);
318
ohci_exynos_cleanup(void)319 static void __exit ohci_exynos_cleanup(void)
320 {
321 platform_driver_unregister(&exynos_ohci_driver);
322 }
323 module_exit(ohci_exynos_cleanup);
324
325 MODULE_ALIAS("platform:exynos-ohci");
326 MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
327 MODULE_LICENSE("GPL v2");
328
