xref: /openbmc/linux/drivers/usb/host/ehci-exynos.c (revision 791d3ef2)
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 phy *phy[PHY_NUMBER];
43 };
44 
45 #define to_exynos_ehci(hcd) (struct exynos_ehci_hcd *)(hcd_to_ehci(hcd)->priv)
46 
47 static int exynos_ehci_get_phy(struct device *dev,
48 				struct exynos_ehci_hcd *exynos_ehci)
49 {
50 	struct device_node *child;
51 	struct phy *phy;
52 	int phy_number;
53 	int ret;
54 
55 	/* Get PHYs for the controller */
56 	for_each_available_child_of_node(dev->of_node, child) {
57 		ret = of_property_read_u32(child, "reg", &phy_number);
58 		if (ret) {
59 			dev_err(dev, "Failed to parse device tree\n");
60 			of_node_put(child);
61 			return ret;
62 		}
63 
64 		if (phy_number >= PHY_NUMBER) {
65 			dev_err(dev, "Invalid number of PHYs\n");
66 			of_node_put(child);
67 			return -EINVAL;
68 		}
69 
70 		phy = devm_of_phy_get(dev, child, NULL);
71 		exynos_ehci->phy[phy_number] = phy;
72 		if (IS_ERR(phy)) {
73 			ret = PTR_ERR(phy);
74 			if (ret == -EPROBE_DEFER) {
75 				of_node_put(child);
76 				return ret;
77 			} else if (ret != -ENOSYS && ret != -ENODEV) {
78 				dev_err(dev,
79 					"Error retrieving usb2 phy: %d\n", ret);
80 				of_node_put(child);
81 				return ret;
82 			}
83 		}
84 	}
85 
86 	return 0;
87 }
88 
89 static int exynos_ehci_phy_enable(struct device *dev)
90 {
91 	struct usb_hcd *hcd = dev_get_drvdata(dev);
92 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
93 	int i;
94 	int ret = 0;
95 
96 	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
97 		if (!IS_ERR(exynos_ehci->phy[i]))
98 			ret = phy_power_on(exynos_ehci->phy[i]);
99 	if (ret)
100 		for (i--; i >= 0; i--)
101 			if (!IS_ERR(exynos_ehci->phy[i]))
102 				phy_power_off(exynos_ehci->phy[i]);
103 
104 	return ret;
105 }
106 
107 static void exynos_ehci_phy_disable(struct device *dev)
108 {
109 	struct usb_hcd *hcd = dev_get_drvdata(dev);
110 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
111 	int i;
112 
113 	for (i = 0; i < PHY_NUMBER; i++)
114 		if (!IS_ERR(exynos_ehci->phy[i]))
115 			phy_power_off(exynos_ehci->phy[i]);
116 }
117 
118 static void exynos_setup_vbus_gpio(struct device *dev)
119 {
120 	int err;
121 	int gpio;
122 
123 	if (!dev->of_node)
124 		return;
125 
126 	gpio = of_get_named_gpio(dev->of_node, "samsung,vbus-gpio", 0);
127 	if (!gpio_is_valid(gpio))
128 		return;
129 
130 	err = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH,
131 				    "ehci_vbus_gpio");
132 	if (err)
133 		dev_err(dev, "can't request ehci vbus gpio %d", gpio);
134 }
135 
136 static int exynos_ehci_probe(struct platform_device *pdev)
137 {
138 	struct exynos_ehci_hcd *exynos_ehci;
139 	struct usb_hcd *hcd;
140 	struct ehci_hcd *ehci;
141 	struct resource *res;
142 	int irq;
143 	int err;
144 
145 	/*
146 	 * Right now device-tree probed devices don't get dma_mask set.
147 	 * Since shared usb code relies on it, set it here for now.
148 	 * Once we move to full device tree support this will vanish off.
149 	 */
150 	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
151 	if (err)
152 		return err;
153 
154 	exynos_setup_vbus_gpio(&pdev->dev);
155 
156 	hcd = usb_create_hcd(&exynos_ehci_hc_driver,
157 			     &pdev->dev, dev_name(&pdev->dev));
158 	if (!hcd) {
159 		dev_err(&pdev->dev, "Unable to create HCD\n");
160 		return -ENOMEM;
161 	}
162 	exynos_ehci = to_exynos_ehci(hcd);
163 
164 	if (of_device_is_compatible(pdev->dev.of_node,
165 					"samsung,exynos5440-ehci"))
166 		goto skip_phy;
167 
168 	err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci);
169 	if (err)
170 		goto fail_clk;
171 
172 skip_phy:
173 
174 	exynos_ehci->clk = devm_clk_get(&pdev->dev, "usbhost");
175 
176 	if (IS_ERR(exynos_ehci->clk)) {
177 		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
178 		err = PTR_ERR(exynos_ehci->clk);
179 		goto fail_clk;
180 	}
181 
182 	err = clk_prepare_enable(exynos_ehci->clk);
183 	if (err)
184 		goto fail_clk;
185 
186 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
187 	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
188 	if (IS_ERR(hcd->regs)) {
189 		err = PTR_ERR(hcd->regs);
190 		goto fail_io;
191 	}
192 
193 	hcd->rsrc_start = res->start;
194 	hcd->rsrc_len = resource_size(res);
195 
196 	irq = platform_get_irq(pdev, 0);
197 	if (!irq) {
198 		dev_err(&pdev->dev, "Failed to get IRQ\n");
199 		err = -ENODEV;
200 		goto fail_io;
201 	}
202 
203 	err = exynos_ehci_phy_enable(&pdev->dev);
204 	if (err) {
205 		dev_err(&pdev->dev, "Failed to enable USB phy\n");
206 		goto fail_io;
207 	}
208 
209 	ehci = hcd_to_ehci(hcd);
210 	ehci->caps = hcd->regs;
211 
212 	/* DMA burst Enable */
213 	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
214 
215 	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
216 	if (err) {
217 		dev_err(&pdev->dev, "Failed to add USB HCD\n");
218 		goto fail_add_hcd;
219 	}
220 	device_wakeup_enable(hcd->self.controller);
221 
222 	platform_set_drvdata(pdev, hcd);
223 
224 	return 0;
225 
226 fail_add_hcd:
227 	exynos_ehci_phy_disable(&pdev->dev);
228 fail_io:
229 	clk_disable_unprepare(exynos_ehci->clk);
230 fail_clk:
231 	usb_put_hcd(hcd);
232 	return err;
233 }
234 
235 static int exynos_ehci_remove(struct platform_device *pdev)
236 {
237 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
238 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
239 
240 	usb_remove_hcd(hcd);
241 
242 	exynos_ehci_phy_disable(&pdev->dev);
243 
244 	clk_disable_unprepare(exynos_ehci->clk);
245 
246 	usb_put_hcd(hcd);
247 
248 	return 0;
249 }
250 
251 #ifdef CONFIG_PM
252 static int exynos_ehci_suspend(struct device *dev)
253 {
254 	struct usb_hcd *hcd = dev_get_drvdata(dev);
255 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
256 
257 	bool do_wakeup = device_may_wakeup(dev);
258 	int rc;
259 
260 	rc = ehci_suspend(hcd, do_wakeup);
261 	if (rc)
262 		return rc;
263 
264 	exynos_ehci_phy_disable(dev);
265 
266 	clk_disable_unprepare(exynos_ehci->clk);
267 
268 	return rc;
269 }
270 
271 static int exynos_ehci_resume(struct device *dev)
272 {
273 	struct usb_hcd *hcd = dev_get_drvdata(dev);
274 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
275 	int ret;
276 
277 	ret = clk_prepare_enable(exynos_ehci->clk);
278 	if (ret)
279 		return ret;
280 
281 	ret = exynos_ehci_phy_enable(dev);
282 	if (ret) {
283 		dev_err(dev, "Failed to enable USB phy\n");
284 		clk_disable_unprepare(exynos_ehci->clk);
285 		return ret;
286 	}
287 
288 	/* DMA burst Enable */
289 	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
290 
291 	ehci_resume(hcd, false);
292 	return 0;
293 }
294 #else
295 #define exynos_ehci_suspend	NULL
296 #define exynos_ehci_resume	NULL
297 #endif
298 
299 static const struct dev_pm_ops exynos_ehci_pm_ops = {
300 	.suspend	= exynos_ehci_suspend,
301 	.resume		= exynos_ehci_resume,
302 };
303 
304 #ifdef CONFIG_OF
305 static const struct of_device_id exynos_ehci_match[] = {
306 	{ .compatible = "samsung,exynos4210-ehci" },
307 	{ .compatible = "samsung,exynos5440-ehci" },
308 	{},
309 };
310 MODULE_DEVICE_TABLE(of, exynos_ehci_match);
311 #endif
312 
313 static struct platform_driver exynos_ehci_driver = {
314 	.probe		= exynos_ehci_probe,
315 	.remove		= exynos_ehci_remove,
316 	.shutdown	= usb_hcd_platform_shutdown,
317 	.driver = {
318 		.name	= "exynos-ehci",
319 		.pm	= &exynos_ehci_pm_ops,
320 		.of_match_table = of_match_ptr(exynos_ehci_match),
321 	}
322 };
323 static const struct ehci_driver_overrides exynos_overrides __initconst = {
324 	.extra_priv_size = sizeof(struct exynos_ehci_hcd),
325 };
326 
327 static int __init ehci_exynos_init(void)
328 {
329 	if (usb_disabled())
330 		return -ENODEV;
331 
332 	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
333 	ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides);
334 	return platform_driver_register(&exynos_ehci_driver);
335 }
336 module_init(ehci_exynos_init);
337 
338 static void __exit ehci_exynos_cleanup(void)
339 {
340 	platform_driver_unregister(&exynos_ehci_driver);
341 }
342 module_exit(ehci_exynos_cleanup);
343 
344 MODULE_DESCRIPTION(DRIVER_DESC);
345 MODULE_ALIAS("platform:exynos-ehci");
346 MODULE_AUTHOR("Jingoo Han");
347 MODULE_AUTHOR("Joonyoung Shim");
348 MODULE_LICENSE("GPL v2");
349