1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * SAMSUNG EXYNOS USB HOST EHCI Controller
4 *
5 * Copyright (C) 2011 Samsung Electronics Co.Ltd
6 * Author: Jingoo Han <jg1.han@samsung.com>
7 * Author: Joonyoung Shim <jy0922.shim@samsung.com>
8 */
9
10 #include <linux/clk.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/io.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/of_gpio.h>
17 #include <linux/phy/phy.h>
18 #include <linux/platform_device.h>
19 #include <linux/usb.h>
20 #include <linux/usb/hcd.h>
21
22 #include "ehci.h"
23
24 #define DRIVER_DESC "EHCI EXYNOS driver"
25
26 #define EHCI_INSNREG00(base) (base + 0x90)
27 #define EHCI_INSNREG00_ENA_INCR16 (0x1 << 25)
28 #define EHCI_INSNREG00_ENA_INCR8 (0x1 << 24)
29 #define EHCI_INSNREG00_ENA_INCR4 (0x1 << 23)
30 #define EHCI_INSNREG00_ENA_INCRX_ALIGN (0x1 << 22)
31 #define EHCI_INSNREG00_ENABLE_DMA_BURST \
32 (EHCI_INSNREG00_ENA_INCR16 | EHCI_INSNREG00_ENA_INCR8 | \
33 EHCI_INSNREG00_ENA_INCR4 | EHCI_INSNREG00_ENA_INCRX_ALIGN)
34
35 static const char hcd_name[] = "ehci-exynos";
36 static struct hc_driver __read_mostly exynos_ehci_hc_driver;
37
38 #define PHY_NUMBER 3
39
40 struct exynos_ehci_hcd {
41 struct clk *clk;
42 struct device_node *of_node;
43 struct phy *phy[PHY_NUMBER];
44 bool legacy_phy;
45 };
46
47 #define to_exynos_ehci(hcd) (struct exynos_ehci_hcd *)(hcd_to_ehci(hcd)->priv)
48
exynos_ehci_get_phy(struct device * dev,struct exynos_ehci_hcd * exynos_ehci)49 static int exynos_ehci_get_phy(struct device *dev,
50 struct exynos_ehci_hcd *exynos_ehci)
51 {
52 struct device_node *child;
53 struct phy *phy;
54 int phy_number, num_phys;
55 int ret;
56
57 /* Get PHYs for the controller */
58 num_phys = of_count_phandle_with_args(dev->of_node, "phys",
59 "#phy-cells");
60 for (phy_number = 0; phy_number < num_phys; phy_number++) {
61 phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number);
62 if (IS_ERR(phy))
63 return PTR_ERR(phy);
64 exynos_ehci->phy[phy_number] = phy;
65 }
66 if (num_phys > 0)
67 return 0;
68
69 /* Get PHYs using legacy bindings */
70 for_each_available_child_of_node(dev->of_node, child) {
71 ret = of_property_read_u32(child, "reg", &phy_number);
72 if (ret) {
73 dev_err(dev, "Failed to parse device tree\n");
74 of_node_put(child);
75 return ret;
76 }
77
78 if (phy_number >= PHY_NUMBER) {
79 dev_err(dev, "Invalid number of PHYs\n");
80 of_node_put(child);
81 return -EINVAL;
82 }
83
84 phy = devm_of_phy_get(dev, child, NULL);
85 exynos_ehci->phy[phy_number] = phy;
86 if (IS_ERR(phy)) {
87 ret = PTR_ERR(phy);
88 if (ret == -EPROBE_DEFER) {
89 of_node_put(child);
90 return ret;
91 } else if (ret != -ENOSYS && ret != -ENODEV) {
92 dev_err(dev,
93 "Error retrieving usb2 phy: %d\n", ret);
94 of_node_put(child);
95 return ret;
96 }
97 }
98 }
99
100 exynos_ehci->legacy_phy = true;
101 return 0;
102 }
103
exynos_ehci_phy_enable(struct device * dev)104 static int exynos_ehci_phy_enable(struct device *dev)
105 {
106 struct usb_hcd *hcd = dev_get_drvdata(dev);
107 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
108 int i;
109 int ret = 0;
110
111 for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
112 if (!IS_ERR(exynos_ehci->phy[i]))
113 ret = phy_power_on(exynos_ehci->phy[i]);
114 if (ret)
115 for (i--; i >= 0; i--)
116 if (!IS_ERR(exynos_ehci->phy[i]))
117 phy_power_off(exynos_ehci->phy[i]);
118
119 return ret;
120 }
121
exynos_ehci_phy_disable(struct device * dev)122 static void exynos_ehci_phy_disable(struct device *dev)
123 {
124 struct usb_hcd *hcd = dev_get_drvdata(dev);
125 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
126 int i;
127
128 for (i = 0; i < PHY_NUMBER; i++)
129 if (!IS_ERR(exynos_ehci->phy[i]))
130 phy_power_off(exynos_ehci->phy[i]);
131 }
132
exynos_setup_vbus_gpio(struct device * dev)133 static void exynos_setup_vbus_gpio(struct device *dev)
134 {
135 int err;
136 int gpio;
137
138 if (!dev->of_node)
139 return;
140
141 gpio = of_get_named_gpio(dev->of_node, "samsung,vbus-gpio", 0);
142 if (!gpio_is_valid(gpio))
143 return;
144
145 err = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH,
146 "ehci_vbus_gpio");
147 if (err)
148 dev_err(dev, "can't request ehci vbus gpio %d", gpio);
149 }
150
exynos_ehci_probe(struct platform_device * pdev)151 static int exynos_ehci_probe(struct platform_device *pdev)
152 {
153 struct exynos_ehci_hcd *exynos_ehci;
154 struct usb_hcd *hcd;
155 struct ehci_hcd *ehci;
156 struct resource *res;
157 int irq;
158 int err;
159
160 /*
161 * Right now device-tree probed devices don't get dma_mask set.
162 * Since shared usb code relies on it, set it here for now.
163 * Once we move to full device tree support this will vanish off.
164 */
165 err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
166 if (err)
167 return err;
168
169 exynos_setup_vbus_gpio(&pdev->dev);
170
171 hcd = usb_create_hcd(&exynos_ehci_hc_driver,
172 &pdev->dev, dev_name(&pdev->dev));
173 if (!hcd) {
174 dev_err(&pdev->dev, "Unable to create HCD\n");
175 return -ENOMEM;
176 }
177 exynos_ehci = to_exynos_ehci(hcd);
178
179 err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci);
180 if (err)
181 goto fail_clk;
182
183 exynos_ehci->clk = devm_clk_get(&pdev->dev, "usbhost");
184
185 if (IS_ERR(exynos_ehci->clk)) {
186 dev_err(&pdev->dev, "Failed to get usbhost clock\n");
187 err = PTR_ERR(exynos_ehci->clk);
188 goto fail_clk;
189 }
190
191 err = clk_prepare_enable(exynos_ehci->clk);
192 if (err)
193 goto fail_clk;
194
195 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
196 hcd->regs = devm_ioremap_resource(&pdev->dev, res);
197 if (IS_ERR(hcd->regs)) {
198 err = PTR_ERR(hcd->regs);
199 goto fail_io;
200 }
201
202 hcd->rsrc_start = res->start;
203 hcd->rsrc_len = resource_size(res);
204
205 irq = platform_get_irq(pdev, 0);
206 if (!irq) {
207 dev_err(&pdev->dev, "Failed to get IRQ\n");
208 err = -ENODEV;
209 goto fail_io;
210 }
211
212 err = exynos_ehci_phy_enable(&pdev->dev);
213 if (err) {
214 dev_err(&pdev->dev, "Failed to enable USB phy\n");
215 goto fail_io;
216 }
217
218 ehci = hcd_to_ehci(hcd);
219 ehci->caps = hcd->regs;
220
221 /*
222 * Workaround: reset of_node pointer to avoid conflict between legacy
223 * Exynos EHCI port subnodes and generic USB device bindings
224 */
225 exynos_ehci->of_node = pdev->dev.of_node;
226 if (exynos_ehci->legacy_phy)
227 pdev->dev.of_node = NULL;
228
229 /* DMA burst Enable */
230 writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
231
232 err = usb_add_hcd(hcd, irq, IRQF_SHARED);
233 if (err) {
234 dev_err(&pdev->dev, "Failed to add USB HCD\n");
235 goto fail_add_hcd;
236 }
237 device_wakeup_enable(hcd->self.controller);
238
239 platform_set_drvdata(pdev, hcd);
240
241 return 0;
242
243 fail_add_hcd:
244 exynos_ehci_phy_disable(&pdev->dev);
245 pdev->dev.of_node = exynos_ehci->of_node;
246 fail_io:
247 clk_disable_unprepare(exynos_ehci->clk);
248 fail_clk:
249 usb_put_hcd(hcd);
250 return err;
251 }
252
exynos_ehci_remove(struct platform_device * pdev)253 static int exynos_ehci_remove(struct platform_device *pdev)
254 {
255 struct usb_hcd *hcd = platform_get_drvdata(pdev);
256 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
257
258 pdev->dev.of_node = exynos_ehci->of_node;
259
260 usb_remove_hcd(hcd);
261
262 exynos_ehci_phy_disable(&pdev->dev);
263
264 clk_disable_unprepare(exynos_ehci->clk);
265
266 usb_put_hcd(hcd);
267
268 return 0;
269 }
270
271 #ifdef CONFIG_PM
exynos_ehci_suspend(struct device * dev)272 static int exynos_ehci_suspend(struct device *dev)
273 {
274 struct usb_hcd *hcd = dev_get_drvdata(dev);
275 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
276
277 bool do_wakeup = device_may_wakeup(dev);
278 int rc;
279
280 rc = ehci_suspend(hcd, do_wakeup);
281 if (rc)
282 return rc;
283
284 exynos_ehci_phy_disable(dev);
285
286 clk_disable_unprepare(exynos_ehci->clk);
287
288 return rc;
289 }
290
exynos_ehci_resume(struct device * dev)291 static int exynos_ehci_resume(struct device *dev)
292 {
293 struct usb_hcd *hcd = dev_get_drvdata(dev);
294 struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
295 int ret;
296
297 ret = clk_prepare_enable(exynos_ehci->clk);
298 if (ret)
299 return ret;
300
301 ret = exynos_ehci_phy_enable(dev);
302 if (ret) {
303 dev_err(dev, "Failed to enable USB phy\n");
304 clk_disable_unprepare(exynos_ehci->clk);
305 return ret;
306 }
307
308 /* DMA burst Enable */
309 writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
310
311 ehci_resume(hcd, false);
312 return 0;
313 }
314 #else
315 #define exynos_ehci_suspend NULL
316 #define exynos_ehci_resume NULL
317 #endif
318
319 static const struct dev_pm_ops exynos_ehci_pm_ops = {
320 .suspend = exynos_ehci_suspend,
321 .resume = exynos_ehci_resume,
322 };
323
324 #ifdef CONFIG_OF
325 static const struct of_device_id exynos_ehci_match[] = {
326 { .compatible = "samsung,exynos4210-ehci" },
327 {},
328 };
329 MODULE_DEVICE_TABLE(of, exynos_ehci_match);
330 #endif
331
332 static struct platform_driver exynos_ehci_driver = {
333 .probe = exynos_ehci_probe,
334 .remove = exynos_ehci_remove,
335 .shutdown = usb_hcd_platform_shutdown,
336 .driver = {
337 .name = "exynos-ehci",
338 .pm = &exynos_ehci_pm_ops,
339 .of_match_table = of_match_ptr(exynos_ehci_match),
340 }
341 };
342 static const struct ehci_driver_overrides exynos_overrides __initconst = {
343 .extra_priv_size = sizeof(struct exynos_ehci_hcd),
344 };
345
ehci_exynos_init(void)346 static int __init ehci_exynos_init(void)
347 {
348 if (usb_disabled())
349 return -ENODEV;
350
351 pr_info("%s: " DRIVER_DESC "\n", hcd_name);
352 ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides);
353 return platform_driver_register(&exynos_ehci_driver);
354 }
355 module_init(ehci_exynos_init);
356
ehci_exynos_cleanup(void)357 static void __exit ehci_exynos_cleanup(void)
358 {
359 platform_driver_unregister(&exynos_ehci_driver);
360 }
361 module_exit(ehci_exynos_cleanup);
362
363 MODULE_DESCRIPTION(DRIVER_DESC);
364 MODULE_ALIAS("platform:exynos-ehci");
365 MODULE_AUTHOR("Jingoo Han");
366 MODULE_AUTHOR("Joonyoung Shim");
367 MODULE_LICENSE("GPL v2");
368
