1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * SAMSUNG EXYNOS USB HOST OHCI Controller
4 *
5 * Copyright (C) 2011 Samsung Electronics Co.Ltd
6 * Author: Jingoo Han <jg1.han@samsung.com>
7 */
8
9#include <linux/clk.h>
10#include <linux/dma-mapping.h>
11#include <linux/io.h>
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/of.h>
15#include <linux/platform_device.h>
16#include <linux/phy/phy.h>
17#include <linux/usb.h>
18#include <linux/usb/hcd.h>
19
20#include "ohci.h"
21
22#define DRIVER_DESC "OHCI Exynos driver"
23
24static struct hc_driver __read_mostly exynos_ohci_hc_driver;
25
26#define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv)
27
28#define PHY_NUMBER 3
29
30struct exynos_ohci_hcd {
31	struct clk *clk;
32	struct device_node *of_node;
33	struct phy *phy[PHY_NUMBER];
34	bool legacy_phy;
35};
36
37static int exynos_ohci_get_phy(struct device *dev,
38				struct exynos_ohci_hcd *exynos_ohci)
39{
40	struct device_node *child;
41	struct phy *phy;
42	int phy_number, num_phys;
43	int ret;
44
45	/* Get PHYs for the controller */
46	num_phys = of_count_phandle_with_args(dev->of_node, "phys",
47					      "#phy-cells");
48	for (phy_number = 0; phy_number < num_phys; phy_number++) {
49		phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number);
50		if (IS_ERR(phy))
51			return PTR_ERR(phy);
52		exynos_ohci->phy[phy_number] = phy;
53	}
54	if (num_phys > 0)
55		return 0;
56
57	/* Get PHYs using legacy bindings */
58	for_each_available_child_of_node(dev->of_node, child) {
59		ret = of_property_read_u32(child, "reg", &phy_number);
60		if (ret) {
61			dev_err(dev, "Failed to parse device tree\n");
62			of_node_put(child);
63			return ret;
64		}
65
66		if (phy_number >= PHY_NUMBER) {
67			dev_err(dev, "Invalid number of PHYs\n");
68			of_node_put(child);
69			return -EINVAL;
70		}
71
72		phy = devm_of_phy_optional_get(dev, child, NULL);
73		exynos_ohci->phy[phy_number] = phy;
74		if (IS_ERR(phy)) {
75			of_node_put(child);
76			return PTR_ERR(phy);
77		}
78	}
79
80	exynos_ohci->legacy_phy = true;
81	return 0;
82}
83
84static int exynos_ohci_phy_enable(struct device *dev)
85{
86	struct usb_hcd *hcd = dev_get_drvdata(dev);
87	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
88	int i;
89	int ret = 0;
90
91	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
92		ret = phy_power_on(exynos_ohci->phy[i]);
93	if (ret)
94		for (i--; i >= 0; i--)
95			phy_power_off(exynos_ohci->phy[i]);
96
97	return ret;
98}
99
100static void exynos_ohci_phy_disable(struct device *dev)
101{
102	struct usb_hcd *hcd = dev_get_drvdata(dev);
103	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
104	int i;
105
106	for (i = 0; i < PHY_NUMBER; i++)
107		phy_power_off(exynos_ohci->phy[i]);
108}
109
110static int exynos_ohci_probe(struct platform_device *pdev)
111{
112	struct exynos_ohci_hcd *exynos_ohci;
113	struct usb_hcd *hcd;
114	struct resource *res;
115	int irq;
116	int err;
117
118	/*
119	 * Right now device-tree probed devices don't get dma_mask set.
120	 * Since shared usb code relies on it, set it here for now.
121	 * Once we move to full device tree support this will vanish off.
122	 */
123	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
124	if (err)
125		return err;
126
127	hcd = usb_create_hcd(&exynos_ohci_hc_driver,
128				&pdev->dev, dev_name(&pdev->dev));
129	if (!hcd) {
130		dev_err(&pdev->dev, "Unable to create HCD\n");
131		return -ENOMEM;
132	}
133
134	exynos_ohci = to_exynos_ohci(hcd);
135
136	err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
137	if (err)
138		goto fail_clk;
139
140	exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
141
142	if (IS_ERR(exynos_ohci->clk)) {
143		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
144		err = PTR_ERR(exynos_ohci->clk);
145		goto fail_clk;
146	}
147
148	err = clk_prepare_enable(exynos_ohci->clk);
149	if (err)
150		goto fail_clk;
151
152	hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
153	if (IS_ERR(hcd->regs)) {
154		err = PTR_ERR(hcd->regs);
155		goto fail_io;
156	}
157	hcd->rsrc_start = res->start;
158	hcd->rsrc_len = resource_size(res);
159
160	irq = platform_get_irq(pdev, 0);
161	if (irq < 0) {
162		err = irq;
163		goto fail_io;
164	}
165
166	platform_set_drvdata(pdev, hcd);
167
168	err = exynos_ohci_phy_enable(&pdev->dev);
169	if (err) {
170		dev_err(&pdev->dev, "Failed to enable USB phy\n");
171		goto fail_io;
172	}
173
174	/*
175	 * Workaround: reset of_node pointer to avoid conflict between legacy
176	 * Exynos OHCI port subnodes and generic USB device bindings
177	 */
178	exynos_ohci->of_node = pdev->dev.of_node;
179	if (exynos_ohci->legacy_phy)
180		pdev->dev.of_node = NULL;
181
182	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
183	if (err) {
184		dev_err(&pdev->dev, "Failed to add USB HCD\n");
185		goto fail_add_hcd;
186	}
187	device_wakeup_enable(hcd->self.controller);
188	return 0;
189
190fail_add_hcd:
191	exynos_ohci_phy_disable(&pdev->dev);
192	pdev->dev.of_node = exynos_ohci->of_node;
193fail_io:
194	clk_disable_unprepare(exynos_ohci->clk);
195fail_clk:
196	usb_put_hcd(hcd);
197	return err;
198}
199
200static void exynos_ohci_remove(struct platform_device *pdev)
201{
202	struct usb_hcd *hcd = platform_get_drvdata(pdev);
203	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
204
205	pdev->dev.of_node = exynos_ohci->of_node;
206
207	usb_remove_hcd(hcd);
208
209	exynos_ohci_phy_disable(&pdev->dev);
210
211	clk_disable_unprepare(exynos_ohci->clk);
212
213	usb_put_hcd(hcd);
214}
215
216static void exynos_ohci_shutdown(struct platform_device *pdev)
217{
218	struct usb_hcd *hcd = platform_get_drvdata(pdev);
219
220	if (hcd->driver->shutdown)
221		hcd->driver->shutdown(hcd);
222}
223
224#ifdef CONFIG_PM
225static int exynos_ohci_suspend(struct device *dev)
226{
227	struct usb_hcd *hcd = dev_get_drvdata(dev);
228	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
229	bool do_wakeup = device_may_wakeup(dev);
230	int rc = ohci_suspend(hcd, do_wakeup);
231
232	if (rc)
233		return rc;
234
235	exynos_ohci_phy_disable(dev);
236
237	clk_disable_unprepare(exynos_ohci->clk);
238
239	return 0;
240}
241
242static int exynos_ohci_resume(struct device *dev)
243{
244	struct usb_hcd *hcd			= dev_get_drvdata(dev);
245	struct exynos_ohci_hcd *exynos_ohci	= to_exynos_ohci(hcd);
246	int ret;
247
248	clk_prepare_enable(exynos_ohci->clk);
249
250	ret = exynos_ohci_phy_enable(dev);
251	if (ret) {
252		dev_err(dev, "Failed to enable USB phy\n");
253		clk_disable_unprepare(exynos_ohci->clk);
254		return ret;
255	}
256
257	ohci_resume(hcd, false);
258
259	return 0;
260}
261#else
262#define exynos_ohci_suspend	NULL
263#define exynos_ohci_resume	NULL
264#endif
265
266static const struct ohci_driver_overrides exynos_overrides __initconst = {
267	.extra_priv_size =	sizeof(struct exynos_ohci_hcd),
268};
269
270static const struct dev_pm_ops exynos_ohci_pm_ops = {
271	.suspend	= exynos_ohci_suspend,
272	.resume		= exynos_ohci_resume,
273};
274
275#ifdef CONFIG_OF
276static const struct of_device_id exynos_ohci_match[] = {
277	{ .compatible = "samsung,exynos4210-ohci" },
278	{},
279};
280MODULE_DEVICE_TABLE(of, exynos_ohci_match);
281#endif
282
283static struct platform_driver exynos_ohci_driver = {
284	.probe		= exynos_ohci_probe,
285	.remove_new	= exynos_ohci_remove,
286	.shutdown	= exynos_ohci_shutdown,
287	.driver = {
288		.name	= "exynos-ohci",
289		.pm	= &exynos_ohci_pm_ops,
290		.of_match_table	= of_match_ptr(exynos_ohci_match),
291	}
292};
293static int __init ohci_exynos_init(void)
294{
295	if (usb_disabled())
296		return -ENODEV;
297
298	ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
299	return platform_driver_register(&exynos_ohci_driver);
300}
301module_init(ohci_exynos_init);
302
303static void __exit ohci_exynos_cleanup(void)
304{
305	platform_driver_unregister(&exynos_ohci_driver);
306}
307module_exit(ohci_exynos_cleanup);
308
309MODULE_ALIAS("platform:exynos-ohci");
310MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
311MODULE_LICENSE("GPL v2");
312