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