xref: /openbmc/linux/drivers/usb/host/ehci-exynos.c (revision 6d99a79c)
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 	err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci);
165 	if (err)
166 		goto fail_clk;
167 
168 	exynos_ehci->clk = devm_clk_get(&pdev->dev, "usbhost");
169 
170 	if (IS_ERR(exynos_ehci->clk)) {
171 		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
172 		err = PTR_ERR(exynos_ehci->clk);
173 		goto fail_clk;
174 	}
175 
176 	err = clk_prepare_enable(exynos_ehci->clk);
177 	if (err)
178 		goto fail_clk;
179 
180 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
181 	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
182 	if (IS_ERR(hcd->regs)) {
183 		err = PTR_ERR(hcd->regs);
184 		goto fail_io;
185 	}
186 
187 	hcd->rsrc_start = res->start;
188 	hcd->rsrc_len = resource_size(res);
189 
190 	irq = platform_get_irq(pdev, 0);
191 	if (!irq) {
192 		dev_err(&pdev->dev, "Failed to get IRQ\n");
193 		err = -ENODEV;
194 		goto fail_io;
195 	}
196 
197 	err = exynos_ehci_phy_enable(&pdev->dev);
198 	if (err) {
199 		dev_err(&pdev->dev, "Failed to enable USB phy\n");
200 		goto fail_io;
201 	}
202 
203 	ehci = hcd_to_ehci(hcd);
204 	ehci->caps = hcd->regs;
205 
206 	/* DMA burst Enable */
207 	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
208 
209 	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
210 	if (err) {
211 		dev_err(&pdev->dev, "Failed to add USB HCD\n");
212 		goto fail_add_hcd;
213 	}
214 	device_wakeup_enable(hcd->self.controller);
215 
216 	platform_set_drvdata(pdev, hcd);
217 
218 	return 0;
219 
220 fail_add_hcd:
221 	exynos_ehci_phy_disable(&pdev->dev);
222 fail_io:
223 	clk_disable_unprepare(exynos_ehci->clk);
224 fail_clk:
225 	usb_put_hcd(hcd);
226 	return err;
227 }
228 
229 static int exynos_ehci_remove(struct platform_device *pdev)
230 {
231 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
232 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
233 
234 	usb_remove_hcd(hcd);
235 
236 	exynos_ehci_phy_disable(&pdev->dev);
237 
238 	clk_disable_unprepare(exynos_ehci->clk);
239 
240 	usb_put_hcd(hcd);
241 
242 	return 0;
243 }
244 
245 #ifdef CONFIG_PM
246 static int exynos_ehci_suspend(struct device *dev)
247 {
248 	struct usb_hcd *hcd = dev_get_drvdata(dev);
249 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
250 
251 	bool do_wakeup = device_may_wakeup(dev);
252 	int rc;
253 
254 	rc = ehci_suspend(hcd, do_wakeup);
255 	if (rc)
256 		return rc;
257 
258 	exynos_ehci_phy_disable(dev);
259 
260 	clk_disable_unprepare(exynos_ehci->clk);
261 
262 	return rc;
263 }
264 
265 static int exynos_ehci_resume(struct device *dev)
266 {
267 	struct usb_hcd *hcd = dev_get_drvdata(dev);
268 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
269 	int ret;
270 
271 	ret = clk_prepare_enable(exynos_ehci->clk);
272 	if (ret)
273 		return ret;
274 
275 	ret = exynos_ehci_phy_enable(dev);
276 	if (ret) {
277 		dev_err(dev, "Failed to enable USB phy\n");
278 		clk_disable_unprepare(exynos_ehci->clk);
279 		return ret;
280 	}
281 
282 	/* DMA burst Enable */
283 	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
284 
285 	ehci_resume(hcd, false);
286 	return 0;
287 }
288 #else
289 #define exynos_ehci_suspend	NULL
290 #define exynos_ehci_resume	NULL
291 #endif
292 
293 static const struct dev_pm_ops exynos_ehci_pm_ops = {
294 	.suspend	= exynos_ehci_suspend,
295 	.resume		= exynos_ehci_resume,
296 };
297 
298 #ifdef CONFIG_OF
299 static const struct of_device_id exynos_ehci_match[] = {
300 	{ .compatible = "samsung,exynos4210-ehci" },
301 	{},
302 };
303 MODULE_DEVICE_TABLE(of, exynos_ehci_match);
304 #endif
305 
306 static struct platform_driver exynos_ehci_driver = {
307 	.probe		= exynos_ehci_probe,
308 	.remove		= exynos_ehci_remove,
309 	.shutdown	= usb_hcd_platform_shutdown,
310 	.driver = {
311 		.name	= "exynos-ehci",
312 		.pm	= &exynos_ehci_pm_ops,
313 		.of_match_table = of_match_ptr(exynos_ehci_match),
314 	}
315 };
316 static const struct ehci_driver_overrides exynos_overrides __initconst = {
317 	.extra_priv_size = sizeof(struct exynos_ehci_hcd),
318 };
319 
320 static int __init ehci_exynos_init(void)
321 {
322 	if (usb_disabled())
323 		return -ENODEV;
324 
325 	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
326 	ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides);
327 	return platform_driver_register(&exynos_ehci_driver);
328 }
329 module_init(ehci_exynos_init);
330 
331 static void __exit ehci_exynos_cleanup(void)
332 {
333 	platform_driver_unregister(&exynos_ehci_driver);
334 }
335 module_exit(ehci_exynos_cleanup);
336 
337 MODULE_DESCRIPTION(DRIVER_DESC);
338 MODULE_ALIAS("platform:exynos-ehci");
339 MODULE_AUTHOR("Jingoo Han");
340 MODULE_AUTHOR("Joonyoung Shim");
341 MODULE_LICENSE("GPL v2");
342