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 phy *phy;
 41	int phy_number, num_phys;
 42	int ret;
 43
 44	/* Get PHYs for the controller */
 45	num_phys = of_count_phandle_with_args(dev->of_node, "phys",
 46					      "#phy-cells");
 47	for (phy_number = 0; phy_number < num_phys; phy_number++) {
 48		phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number);
 49		if (IS_ERR(phy))
 50			return PTR_ERR(phy);
 51		exynos_ohci->phy[phy_number] = phy;
 52	}
 53	if (num_phys > 0)
 54		return 0;
 55
 56	/* Get PHYs using legacy bindings */
 57	for_each_available_child_of_node_scoped(dev->of_node, child) {
 58		ret = of_property_read_u32(child, "reg", &phy_number);
 59		if (ret) {
 60			dev_err(dev, "Failed to parse device tree\n");
 61			return ret;
 62		}
 63
 64		if (phy_number >= PHY_NUMBER) {
 65			dev_err(dev, "Invalid number of PHYs\n");
 66			return -EINVAL;
 67		}
 68
 69		phy = devm_of_phy_optional_get(dev, child, NULL);
 70		exynos_ohci->phy[phy_number] = phy;
 71		if (IS_ERR(phy))
 72			return PTR_ERR(phy);
 73	}
 74
 75	exynos_ohci->legacy_phy = true;
 76	return 0;
 77}
 78
 79static int exynos_ohci_phy_enable(struct device *dev)
 80{
 81	struct usb_hcd *hcd = dev_get_drvdata(dev);
 82	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 83	int i;
 84	int ret = 0;
 85
 86	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
 87		ret = phy_power_on(exynos_ohci->phy[i]);
 88	if (ret)
 89		for (i--; i >= 0; i--)
 90			phy_power_off(exynos_ohci->phy[i]);
 91
 92	return ret;
 93}
 94
 95static void exynos_ohci_phy_disable(struct device *dev)
 96{
 97	struct usb_hcd *hcd = dev_get_drvdata(dev);
 98	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 99	int i;
100
101	for (i = 0; i < PHY_NUMBER; i++)
102		phy_power_off(exynos_ohci->phy[i]);
103}
104
105static int exynos_ohci_probe(struct platform_device *pdev)
106{
107	struct exynos_ohci_hcd *exynos_ohci;
108	struct usb_hcd *hcd;
109	struct resource *res;
110	int irq;
111	int err;
112
113	/*
114	 * Right now device-tree probed devices don't get dma_mask set.
115	 * Since shared usb code relies on it, set it here for now.
116	 * Once we move to full device tree support this will vanish off.
117	 */
118	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
119	if (err)
120		return err;
121
122	hcd = usb_create_hcd(&exynos_ohci_hc_driver,
123				&pdev->dev, dev_name(&pdev->dev));
124	if (!hcd) {
125		dev_err(&pdev->dev, "Unable to create HCD\n");
126		return -ENOMEM;
127	}
128
129	exynos_ohci = to_exynos_ohci(hcd);
130
131	err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
132	if (err)
133		goto fail_io;
134
135	exynos_ohci->clk = devm_clk_get_enabled(&pdev->dev, "usbhost");
136
137	if (IS_ERR(exynos_ohci->clk)) {
138		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
139		err = PTR_ERR(exynos_ohci->clk);
140		goto fail_io;
141	}
142
143	hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
144	if (IS_ERR(hcd->regs)) {
145		err = PTR_ERR(hcd->regs);
146		goto fail_io;
147	}
148	hcd->rsrc_start = res->start;
149	hcd->rsrc_len = resource_size(res);
150
151	irq = platform_get_irq(pdev, 0);
152	if (irq < 0) {
153		err = irq;
154		goto fail_io;
155	}
156
157	platform_set_drvdata(pdev, hcd);
158
159	err = exynos_ohci_phy_enable(&pdev->dev);
160	if (err) {
161		dev_err(&pdev->dev, "Failed to enable USB phy\n");
162		goto fail_io;
163	}
164
165	/*
166	 * Workaround: reset of_node pointer to avoid conflict between legacy
167	 * Exynos OHCI port subnodes and generic USB device bindings
168	 */
169	exynos_ohci->of_node = pdev->dev.of_node;
170	if (exynos_ohci->legacy_phy)
171		pdev->dev.of_node = NULL;
172
173	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
174	if (err) {
175		dev_err(&pdev->dev, "Failed to add USB HCD\n");
176		goto fail_add_hcd;
177	}
178	device_wakeup_enable(hcd->self.controller);
179	return 0;
180
181fail_add_hcd:
182	exynos_ohci_phy_disable(&pdev->dev);
183	pdev->dev.of_node = exynos_ohci->of_node;
184fail_io:
185	usb_put_hcd(hcd);
186	return err;
187}
188
189static void exynos_ohci_remove(struct platform_device *pdev)
190{
191	struct usb_hcd *hcd = platform_get_drvdata(pdev);
192	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
193
194	pdev->dev.of_node = exynos_ohci->of_node;
195
196	usb_remove_hcd(hcd);
197
198	exynos_ohci_phy_disable(&pdev->dev);
199
200	usb_put_hcd(hcd);
201}
202
203static void exynos_ohci_shutdown(struct platform_device *pdev)
204{
205	struct usb_hcd *hcd = platform_get_drvdata(pdev);
206
207	if (hcd->driver->shutdown)
208		hcd->driver->shutdown(hcd);
209}
210
211static int exynos_ohci_suspend(struct device *dev)
212{
213	struct usb_hcd *hcd = dev_get_drvdata(dev);
214	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
215	bool do_wakeup = device_may_wakeup(dev);
216	int rc = ohci_suspend(hcd, do_wakeup);
217
218	if (rc)
219		return rc;
220
221	exynos_ohci_phy_disable(dev);
222
223	clk_disable_unprepare(exynos_ohci->clk);
224
225	return 0;
226}
227
228static int exynos_ohci_resume(struct device *dev)
229{
230	struct usb_hcd *hcd			= dev_get_drvdata(dev);
231	struct exynos_ohci_hcd *exynos_ohci	= to_exynos_ohci(hcd);
232	int ret;
233
234	clk_prepare_enable(exynos_ohci->clk);
235
236	ret = exynos_ohci_phy_enable(dev);
237	if (ret) {
238		dev_err(dev, "Failed to enable USB phy\n");
239		clk_disable_unprepare(exynos_ohci->clk);
240		return ret;
241	}
242
243	ohci_resume(hcd, false);
244
245	return 0;
246}
247
248static const struct ohci_driver_overrides exynos_overrides __initconst = {
249	.extra_priv_size =	sizeof(struct exynos_ohci_hcd),
250};
251
252static DEFINE_SIMPLE_DEV_PM_OPS(exynos_ohci_pm_ops,
253				exynos_ohci_suspend, exynos_ohci_resume);
254
255#ifdef CONFIG_OF
256static const struct of_device_id exynos_ohci_match[] = {
257	{ .compatible = "samsung,exynos4210-ohci" },
258	{},
259};
260MODULE_DEVICE_TABLE(of, exynos_ohci_match);
261#endif
262
263static struct platform_driver exynos_ohci_driver = {
264	.probe		= exynos_ohci_probe,
265	.remove		= exynos_ohci_remove,
266	.shutdown	= exynos_ohci_shutdown,
267	.driver = {
268		.name	= "exynos-ohci",
269		.pm	= pm_ptr(&exynos_ohci_pm_ops),
270		.of_match_table	= of_match_ptr(exynos_ohci_match),
271	}
272};
273static int __init ohci_exynos_init(void)
274{
275	if (usb_disabled())
276		return -ENODEV;
277
278	ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
279	return platform_driver_register(&exynos_ohci_driver);
280}
281module_init(ohci_exynos_init);
282
283static void __exit ohci_exynos_cleanup(void)
284{
285	platform_driver_unregister(&exynos_ohci_driver);
286}
287module_exit(ohci_exynos_cleanup);
288
289MODULE_ALIAS("platform:exynos-ohci");
290MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
291MODULE_DESCRIPTION("OHCI support for Samsung S5P/Exynos SoC Series");
292MODULE_LICENSE("GPL v2");