xref: /openbmc/linux/drivers/usb/host/ehci-exynos.c (revision 1a4e39c2e5ca2eb494a53ecd73055562f690bca0)
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 		of_node_put(child);
78 		if (IS_ERR(phy)) {
79 			ret = PTR_ERR(phy);
80 			if (ret == -EPROBE_DEFER) {
81 				return ret;
82 			} else if (ret != -ENOSYS && ret != -ENODEV) {
83 				dev_err(dev,
84 					"Error retrieving usb2 phy: %d\n", ret);
85 				return ret;
86 			}
87 		}
88 	}
89 
90 	return 0;
91 }
92 
93 static int exynos_ehci_phy_enable(struct device *dev)
94 {
95 	struct usb_hcd *hcd = dev_get_drvdata(dev);
96 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
97 	int i;
98 	int ret = 0;
99 
100 	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
101 		if (!IS_ERR(exynos_ehci->phy[i]))
102 			ret = phy_power_on(exynos_ehci->phy[i]);
103 	if (ret)
104 		for (i--; i >= 0; i--)
105 			if (!IS_ERR(exynos_ehci->phy[i]))
106 				phy_power_off(exynos_ehci->phy[i]);
107 
108 	return ret;
109 }
110 
111 static void exynos_ehci_phy_disable(struct device *dev)
112 {
113 	struct usb_hcd *hcd = dev_get_drvdata(dev);
114 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
115 	int i;
116 
117 	for (i = 0; i < PHY_NUMBER; i++)
118 		if (!IS_ERR(exynos_ehci->phy[i]))
119 			phy_power_off(exynos_ehci->phy[i]);
120 }
121 
122 static void exynos_setup_vbus_gpio(struct device *dev)
123 {
124 	int err;
125 	int gpio;
126 
127 	if (!dev->of_node)
128 		return;
129 
130 	gpio = of_get_named_gpio(dev->of_node, "samsung,vbus-gpio", 0);
131 	if (!gpio_is_valid(gpio))
132 		return;
133 
134 	err = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH,
135 				    "ehci_vbus_gpio");
136 	if (err)
137 		dev_err(dev, "can't request ehci vbus gpio %d", gpio);
138 }
139 
140 static int exynos_ehci_probe(struct platform_device *pdev)
141 {
142 	struct exynos_ehci_hcd *exynos_ehci;
143 	struct usb_hcd *hcd;
144 	struct ehci_hcd *ehci;
145 	struct resource *res;
146 	int irq;
147 	int err;
148 
149 	/*
150 	 * Right now device-tree probed devices don't get dma_mask set.
151 	 * Since shared usb code relies on it, set it here for now.
152 	 * Once we move to full device tree support this will vanish off.
153 	 */
154 	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
155 	if (err)
156 		return err;
157 
158 	exynos_setup_vbus_gpio(&pdev->dev);
159 
160 	hcd = usb_create_hcd(&exynos_ehci_hc_driver,
161 			     &pdev->dev, dev_name(&pdev->dev));
162 	if (!hcd) {
163 		dev_err(&pdev->dev, "Unable to create HCD\n");
164 		return -ENOMEM;
165 	}
166 	exynos_ehci = to_exynos_ehci(hcd);
167 
168 	if (of_device_is_compatible(pdev->dev.of_node,
169 					"samsung,exynos5440-ehci"))
170 		goto skip_phy;
171 
172 	err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci);
173 	if (err)
174 		goto fail_clk;
175 
176 skip_phy:
177 
178 	exynos_ehci->clk = devm_clk_get(&pdev->dev, "usbhost");
179 
180 	if (IS_ERR(exynos_ehci->clk)) {
181 		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
182 		err = PTR_ERR(exynos_ehci->clk);
183 		goto fail_clk;
184 	}
185 
186 	err = clk_prepare_enable(exynos_ehci->clk);
187 	if (err)
188 		goto fail_clk;
189 
190 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
191 	if (!res) {
192 		dev_err(&pdev->dev, "Failed to get I/O memory\n");
193 		err = -ENXIO;
194 		goto fail_io;
195 	}
196 
197 	hcd->rsrc_start = res->start;
198 	hcd->rsrc_len = resource_size(res);
199 	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
200 	if (IS_ERR(hcd->regs)) {
201 		err = PTR_ERR(hcd->regs);
202 		goto fail_io;
203 	}
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 	/* DMA burst Enable */
222 	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
223 
224 	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
225 	if (err) {
226 		dev_err(&pdev->dev, "Failed to add USB HCD\n");
227 		goto fail_add_hcd;
228 	}
229 	device_wakeup_enable(hcd->self.controller);
230 
231 	platform_set_drvdata(pdev, hcd);
232 
233 	return 0;
234 
235 fail_add_hcd:
236 	exynos_ehci_phy_disable(&pdev->dev);
237 fail_io:
238 	clk_disable_unprepare(exynos_ehci->clk);
239 fail_clk:
240 	usb_put_hcd(hcd);
241 	return err;
242 }
243 
244 static int exynos_ehci_remove(struct platform_device *pdev)
245 {
246 	struct usb_hcd *hcd = platform_get_drvdata(pdev);
247 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
248 
249 	usb_remove_hcd(hcd);
250 
251 	exynos_ehci_phy_disable(&pdev->dev);
252 
253 	clk_disable_unprepare(exynos_ehci->clk);
254 
255 	usb_put_hcd(hcd);
256 
257 	return 0;
258 }
259 
260 #ifdef CONFIG_PM
261 static int exynos_ehci_suspend(struct device *dev)
262 {
263 	struct usb_hcd *hcd = dev_get_drvdata(dev);
264 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
265 
266 	bool do_wakeup = device_may_wakeup(dev);
267 	int rc;
268 
269 	rc = ehci_suspend(hcd, do_wakeup);
270 	if (rc)
271 		return rc;
272 
273 	exynos_ehci_phy_disable(dev);
274 
275 	clk_disable_unprepare(exynos_ehci->clk);
276 
277 	return rc;
278 }
279 
280 static int exynos_ehci_resume(struct device *dev)
281 {
282 	struct usb_hcd *hcd = dev_get_drvdata(dev);
283 	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
284 	int ret;
285 
286 	clk_prepare_enable(exynos_ehci->clk);
287 
288 	ret = exynos_ehci_phy_enable(dev);
289 	if (ret) {
290 		dev_err(dev, "Failed to enable USB phy\n");
291 		clk_disable_unprepare(exynos_ehci->clk);
292 		return ret;
293 	}
294 
295 	/* DMA burst Enable */
296 	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
297 
298 	ehci_resume(hcd, false);
299 	return 0;
300 }
301 #else
302 #define exynos_ehci_suspend	NULL
303 #define exynos_ehci_resume	NULL
304 #endif
305 
306 static const struct dev_pm_ops exynos_ehci_pm_ops = {
307 	.suspend	= exynos_ehci_suspend,
308 	.resume		= exynos_ehci_resume,
309 };
310 
311 #ifdef CONFIG_OF
312 static const struct of_device_id exynos_ehci_match[] = {
313 	{ .compatible = "samsung,exynos4210-ehci" },
314 	{ .compatible = "samsung,exynos5440-ehci" },
315 	{},
316 };
317 MODULE_DEVICE_TABLE(of, exynos_ehci_match);
318 #endif
319 
320 static struct platform_driver exynos_ehci_driver = {
321 	.probe		= exynos_ehci_probe,
322 	.remove		= exynos_ehci_remove,
323 	.shutdown	= usb_hcd_platform_shutdown,
324 	.driver = {
325 		.name	= "exynos-ehci",
326 		.owner	= THIS_MODULE,
327 		.pm	= &exynos_ehci_pm_ops,
328 		.of_match_table = of_match_ptr(exynos_ehci_match),
329 	}
330 };
331 static const struct ehci_driver_overrides exynos_overrides __initdata = {
332 	.extra_priv_size = sizeof(struct exynos_ehci_hcd),
333 };
334 
335 static int __init ehci_exynos_init(void)
336 {
337 	if (usb_disabled())
338 		return -ENODEV;
339 
340 	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
341 	ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides);
342 	return platform_driver_register(&exynos_ehci_driver);
343 }
344 module_init(ehci_exynos_init);
345 
346 static void __exit ehci_exynos_cleanup(void)
347 {
348 	platform_driver_unregister(&exynos_ehci_driver);
349 }
350 module_exit(ehci_exynos_cleanup);
351 
352 MODULE_DESCRIPTION(DRIVER_DESC);
353 MODULE_ALIAS("platform:exynos-ehci");
354 MODULE_AUTHOR("Jingoo Han");
355 MODULE_AUTHOR("Joonyoung Shim");
356 MODULE_LICENSE("GPL v2");
357