xref: /openbmc/linux/drivers/usb/host/ehci-exynos.c (revision d2c43ff1)
1 /*
2  * SAMSUNG EXYNOS USB HOST EHCI Controller
3  *
4  * Copyright (C) 2011 Samsung Electronics Co.Ltd
5  * Author: Jingoo Han <jg1.han@samsung.com>
6  * Author: Joonyoung Shim <jy0922.shim@samsung.com>
7  *
8  * This program is free software; you can redistribute  it and/or modify it
9  * under  the terms of  the GNU General  Public License as published by the
10  * Free Software Foundation;  either version 2 of the  License, or (at your
11  * option) any later version.
12  *
13  */
14 
15 #include <linux/clk.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/io.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/of_gpio.h>
22 #include <linux/phy/phy.h>
23 #include <linux/platform_device.h>
24 #include <linux/usb.h>
25 #include <linux/usb/hcd.h>
26 
27 #include "ehci.h"
28 
29 #define DRIVER_DESC "EHCI EXYNOS driver"
30 
31 #define EHCI_INSNREG00(base)			(base + 0x90)
32 #define EHCI_INSNREG00_ENA_INCR16		(0x1 << 25)
33 #define EHCI_INSNREG00_ENA_INCR8		(0x1 << 24)
34 #define EHCI_INSNREG00_ENA_INCR4		(0x1 << 23)
35 #define EHCI_INSNREG00_ENA_INCRX_ALIGN		(0x1 << 22)
36 #define EHCI_INSNREG00_ENABLE_DMA_BURST	\
37 	(EHCI_INSNREG00_ENA_INCR16 | EHCI_INSNREG00_ENA_INCR8 |	\
38 	 EHCI_INSNREG00_ENA_INCR4 | EHCI_INSNREG00_ENA_INCRX_ALIGN)
39 
40 static const char hcd_name[] = "ehci-exynos";
41 static struct hc_driver __read_mostly exynos_ehci_hc_driver;
42 
43 #define PHY_NUMBER 3
44 
45 struct exynos_ehci_hcd {
46 	struct clk *clk;
47 	struct phy *phy[PHY_NUMBER];
48 };
49 
50 #define to_exynos_ehci(hcd) (struct exynos_ehci_hcd *)(hcd_to_ehci(hcd)->priv)
51 
52 static int exynos_ehci_get_phy(struct device *dev,
53 				struct exynos_ehci_hcd *exynos_ehci)
54 {
55 	struct device_node *child;
56 	struct phy *phy;
57 	int phy_number;
58 	int ret;
59 
60 	/* Get PHYs for the controller */
61 	for_each_available_child_of_node(dev->of_node, child) {
62 		ret = of_property_read_u32(child, "reg", &phy_number);
63 		if (ret) {
64 			dev_err(dev, "Failed to parse device tree\n");
65 			of_node_put(child);
66 			return ret;
67 		}
68 
69 		if (phy_number >= PHY_NUMBER) {
70 			dev_err(dev, "Invalid number of PHYs\n");
71 			of_node_put(child);
72 			return -EINVAL;
73 		}
74 
75 		phy = devm_of_phy_get(dev, child, NULL);
76 		exynos_ehci->phy[phy_number] = phy;
77 		if (IS_ERR(phy)) {
78 			ret = PTR_ERR(phy);
79 			if (ret == -EPROBE_DEFER) {
80 				of_node_put(child);
81 				return ret;
82 			} else if (ret != -ENOSYS && ret != -ENODEV) {
83 				dev_err(dev,
84 					"Error retrieving usb2 phy: %d\n", ret);
85 				of_node_put(child);
86 				return ret;
87 			}
88 		}
89 	}
90 
91 	return 0;
92 }
93 
94 static int exynos_ehci_phy_enable(struct device *dev)
95 {
96 	struct usb_hcd *hcd = dev_get_drvdata(dev);
97 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
98 	int i;
99 	int ret = 0;
100 
101 	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
102 		if (!IS_ERR(exynos_ehci->phy[i]))
103 			ret = phy_power_on(exynos_ehci->phy[i]);
104 	if (ret)
105 		for (i--; i >= 0; i--)
106 			if (!IS_ERR(exynos_ehci->phy[i]))
107 				phy_power_off(exynos_ehci->phy[i]);
108 
109 	return ret;
110 }
111 
112 static void exynos_ehci_phy_disable(struct device *dev)
113 {
114 	struct usb_hcd *hcd = dev_get_drvdata(dev);
115 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
116 	int i;
117 
118 	for (i = 0; i < PHY_NUMBER; i++)
119 		if (!IS_ERR(exynos_ehci->phy[i]))
120 			phy_power_off(exynos_ehci->phy[i]);
121 }
122 
123 static void exynos_setup_vbus_gpio(struct device *dev)
124 {
125 	int err;
126 	int gpio;
127 
128 	if (!dev->of_node)
129 		return;
130 
131 	gpio = of_get_named_gpio(dev->of_node, "samsung,vbus-gpio", 0);
132 	if (!gpio_is_valid(gpio))
133 		return;
134 
135 	err = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH,
136 				    "ehci_vbus_gpio");
137 	if (err)
138 		dev_err(dev, "can't request ehci vbus gpio %d", gpio);
139 }
140 
141 static int exynos_ehci_probe(struct platform_device *pdev)
142 {
143 	struct exynos_ehci_hcd *exynos_ehci;
144 	struct usb_hcd *hcd;
145 	struct ehci_hcd *ehci;
146 	struct resource *res;
147 	int irq;
148 	int err;
149 
150 	/*
151 	 * Right now device-tree probed devices don't get dma_mask set.
152 	 * Since shared usb code relies on it, set it here for now.
153 	 * Once we move to full device tree support this will vanish off.
154 	 */
155 	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
156 	if (err)
157 		return err;
158 
159 	exynos_setup_vbus_gpio(&pdev->dev);
160 
161 	hcd = usb_create_hcd(&exynos_ehci_hc_driver,
162 			     &pdev->dev, dev_name(&pdev->dev));
163 	if (!hcd) {
164 		dev_err(&pdev->dev, "Unable to create HCD\n");
165 		return -ENOMEM;
166 	}
167 	exynos_ehci = to_exynos_ehci(hcd);
168 
169 	if (of_device_is_compatible(pdev->dev.of_node,
170 					"samsung,exynos5440-ehci"))
171 		goto skip_phy;
172 
173 	err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci);
174 	if (err)
175 		goto fail_clk;
176 
177 skip_phy:
178 
179 	exynos_ehci->clk = devm_clk_get(&pdev->dev, "usbhost");
180 
181 	if (IS_ERR(exynos_ehci->clk)) {
182 		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
183 		err = PTR_ERR(exynos_ehci->clk);
184 		goto fail_clk;
185 	}
186 
187 	err = clk_prepare_enable(exynos_ehci->clk);
188 	if (err)
189 		goto fail_clk;
190 
191 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
192 	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
193 	if (IS_ERR(hcd->regs)) {
194 		err = PTR_ERR(hcd->regs);
195 		goto fail_io;
196 	}
197 
198 	hcd->rsrc_start = res->start;
199 	hcd->rsrc_len = resource_size(res);
200 
201 	irq = platform_get_irq(pdev, 0);
202 	if (!irq) {
203 		dev_err(&pdev->dev, "Failed to get IRQ\n");
204 		err = -ENODEV;
205 		goto fail_io;
206 	}
207 
208 	err = exynos_ehci_phy_enable(&pdev->dev);
209 	if (err) {
210 		dev_err(&pdev->dev, "Failed to enable USB phy\n");
211 		goto fail_io;
212 	}
213 
214 	ehci = hcd_to_ehci(hcd);
215 	ehci->caps = hcd->regs;
216 
217 	/* DMA burst Enable */
218 	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
219 
220 	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
221 	if (err) {
222 		dev_err(&pdev->dev, "Failed to add USB HCD\n");
223 		goto fail_add_hcd;
224 	}
225 	device_wakeup_enable(hcd->self.controller);
226 
227 	platform_set_drvdata(pdev, hcd);
228 
229 	return 0;
230 
231 fail_add_hcd:
232 	exynos_ehci_phy_disable(&pdev->dev);
233 fail_io:
234 	clk_disable_unprepare(exynos_ehci->clk);
235 fail_clk:
236 	usb_put_hcd(hcd);
237 	return err;
238 }
239 
240 static int exynos_ehci_remove(struct platform_device *pdev)
241 {
242 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
243 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
244 
245 	usb_remove_hcd(hcd);
246 
247 	exynos_ehci_phy_disable(&pdev->dev);
248 
249 	clk_disable_unprepare(exynos_ehci->clk);
250 
251 	usb_put_hcd(hcd);
252 
253 	return 0;
254 }
255 
256 #ifdef CONFIG_PM
257 static int exynos_ehci_suspend(struct device *dev)
258 {
259 	struct usb_hcd *hcd = dev_get_drvdata(dev);
260 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
261 
262 	bool do_wakeup = device_may_wakeup(dev);
263 	int rc;
264 
265 	rc = ehci_suspend(hcd, do_wakeup);
266 	if (rc)
267 		return rc;
268 
269 	exynos_ehci_phy_disable(dev);
270 
271 	clk_disable_unprepare(exynos_ehci->clk);
272 
273 	return rc;
274 }
275 
276 static int exynos_ehci_resume(struct device *dev)
277 {
278 	struct usb_hcd *hcd = dev_get_drvdata(dev);
279 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
280 	int ret;
281 
282 	ret = clk_prepare_enable(exynos_ehci->clk);
283 	if (ret)
284 		return ret;
285 
286 	ret = exynos_ehci_phy_enable(dev);
287 	if (ret) {
288 		dev_err(dev, "Failed to enable USB phy\n");
289 		clk_disable_unprepare(exynos_ehci->clk);
290 		return ret;
291 	}
292 
293 	/* DMA burst Enable */
294 	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
295 
296 	ehci_resume(hcd, false);
297 	return 0;
298 }
299 #else
300 #define exynos_ehci_suspend	NULL
301 #define exynos_ehci_resume	NULL
302 #endif
303 
304 static const struct dev_pm_ops exynos_ehci_pm_ops = {
305 	.suspend	= exynos_ehci_suspend,
306 	.resume		= exynos_ehci_resume,
307 };
308 
309 #ifdef CONFIG_OF
310 static const struct of_device_id exynos_ehci_match[] = {
311 	{ .compatible = "samsung,exynos4210-ehci" },
312 	{ .compatible = "samsung,exynos5440-ehci" },
313 	{},
314 };
315 MODULE_DEVICE_TABLE(of, exynos_ehci_match);
316 #endif
317 
318 static struct platform_driver exynos_ehci_driver = {
319 	.probe		= exynos_ehci_probe,
320 	.remove		= exynos_ehci_remove,
321 	.shutdown	= usb_hcd_platform_shutdown,
322 	.driver = {
323 		.name	= "exynos-ehci",
324 		.pm	= &exynos_ehci_pm_ops,
325 		.of_match_table = of_match_ptr(exynos_ehci_match),
326 	}
327 };
328 static const struct ehci_driver_overrides exynos_overrides __initconst = {
329 	.extra_priv_size = sizeof(struct exynos_ehci_hcd),
330 };
331 
332 static int __init ehci_exynos_init(void)
333 {
334 	if (usb_disabled())
335 		return -ENODEV;
336 
337 	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
338 	ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides);
339 	return platform_driver_register(&exynos_ehci_driver);
340 }
341 module_init(ehci_exynos_init);
342 
343 static void __exit ehci_exynos_cleanup(void)
344 {
345 	platform_driver_unregister(&exynos_ehci_driver);
346 }
347 module_exit(ehci_exynos_cleanup);
348 
349 MODULE_DESCRIPTION(DRIVER_DESC);
350 MODULE_ALIAS("platform:exynos-ehci");
351 MODULE_AUTHOR("Jingoo Han");
352 MODULE_AUTHOR("Joonyoung Shim");
353 MODULE_LICENSE("GPL v2");
354