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 const char hcd_name[] = "ohci-exynos";
 25static struct hc_driver __read_mostly exynos_ohci_hc_driver;
 26
 27#define to_exynos_ohci(hcd) (struct exynos_ohci_hcd *)(hcd_to_ohci(hcd)->priv)
 28
 29#define PHY_NUMBER 3
 30
 31struct exynos_ohci_hcd {
 32	struct clk *clk;
 33	struct device_node *of_node;
 34	struct phy *phy[PHY_NUMBER];
 35	bool legacy_phy;
 36};
 37
 38static int exynos_ohci_get_phy(struct device *dev,
 39				struct exynos_ohci_hcd *exynos_ohci)
 40{
 41	struct device_node *child;
 42	struct phy *phy;
 43	int phy_number, num_phys;
 44	int ret;
 45
 46	/* Get PHYs for the controller */
 47	num_phys = of_count_phandle_with_args(dev->of_node, "phys",
 48					      "#phy-cells");
 49	for (phy_number = 0; phy_number < num_phys; phy_number++) {
 50		phy = devm_of_phy_get_by_index(dev, dev->of_node, phy_number);
 51		if (IS_ERR(phy))
 52			return PTR_ERR(phy);
 53		exynos_ohci->phy[phy_number] = phy;
 54	}
 55	if (num_phys > 0)
 56		return 0;
 57
 58	/* Get PHYs using legacy bindings */
 59	for_each_available_child_of_node(dev->of_node, child) {
 60		ret = of_property_read_u32(child, "reg", &phy_number);
 61		if (ret) {
 62			dev_err(dev, "Failed to parse device tree\n");
 63			of_node_put(child);
 64			return ret;
 65		}
 66
 67		if (phy_number >= PHY_NUMBER) {
 68			dev_err(dev, "Invalid number of PHYs\n");
 69			of_node_put(child);
 70			return -EINVAL;
 71		}
 72
 73		phy = devm_of_phy_get(dev, child, NULL);
 74		exynos_ohci->phy[phy_number] = phy;
 75		if (IS_ERR(phy)) {
 76			ret = PTR_ERR(phy);
 77			if (ret == -EPROBE_DEFER) {
 78				of_node_put(child);
 79				return ret;
 80			} else if (ret != -ENOSYS && ret != -ENODEV) {
 81				dev_err(dev,
 82					"Error retrieving usb2 phy: %d\n", ret);
 83				of_node_put(child);
 84				return ret;
 85			}
 86		}
 87	}
 88
 89	exynos_ohci->legacy_phy = true;
 90	return 0;
 91}
 92
 93static int exynos_ohci_phy_enable(struct device *dev)
 94{
 95	struct usb_hcd *hcd = dev_get_drvdata(dev);
 96	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
 97	int i;
 98	int ret = 0;
 99
100	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
101		if (!IS_ERR(exynos_ohci->phy[i]))
102			ret = phy_power_on(exynos_ohci->phy[i]);
103	if (ret)
104		for (i--; i >= 0; i--)
105			if (!IS_ERR(exynos_ohci->phy[i]))
106				phy_power_off(exynos_ohci->phy[i]);
107
108	return ret;
109}
110
111static void exynos_ohci_phy_disable(struct device *dev)
112{
113	struct usb_hcd *hcd = dev_get_drvdata(dev);
114	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
115	int i;
116
117	for (i = 0; i < PHY_NUMBER; i++)
118		if (!IS_ERR(exynos_ohci->phy[i]))
119			phy_power_off(exynos_ohci->phy[i]);
120}
121
122static int exynos_ohci_probe(struct platform_device *pdev)
123{
124	struct exynos_ohci_hcd *exynos_ohci;
125	struct usb_hcd *hcd;
126	struct resource *res;
127	int irq;
128	int err;
129
130	/*
131	 * Right now device-tree probed devices don't get dma_mask set.
132	 * Since shared usb code relies on it, set it here for now.
133	 * Once we move to full device tree support this will vanish off.
134	 */
135	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
136	if (err)
137		return err;
138
139	hcd = usb_create_hcd(&exynos_ohci_hc_driver,
140				&pdev->dev, dev_name(&pdev->dev));
141	if (!hcd) {
142		dev_err(&pdev->dev, "Unable to create HCD\n");
143		return -ENOMEM;
144	}
145
146	exynos_ohci = to_exynos_ohci(hcd);
147
148	err = exynos_ohci_get_phy(&pdev->dev, exynos_ohci);
149	if (err)
150		goto fail_clk;
151
152	exynos_ohci->clk = devm_clk_get(&pdev->dev, "usbhost");
153
154	if (IS_ERR(exynos_ohci->clk)) {
155		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
156		err = PTR_ERR(exynos_ohci->clk);
157		goto fail_clk;
158	}
159
160	err = clk_prepare_enable(exynos_ohci->clk);
161	if (err)
162		goto fail_clk;
163
164	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
165	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
166	if (IS_ERR(hcd->regs)) {
167		err = PTR_ERR(hcd->regs);
168		goto fail_io;
169	}
170	hcd->rsrc_start = res->start;
171	hcd->rsrc_len = resource_size(res);
172
173	irq = platform_get_irq(pdev, 0);
174	if (!irq) {
175		dev_err(&pdev->dev, "Failed to get IRQ\n");
176		err = -ENODEV;
177		goto fail_io;
178	}
179
180	platform_set_drvdata(pdev, hcd);
181
182	err = exynos_ohci_phy_enable(&pdev->dev);
183	if (err) {
184		dev_err(&pdev->dev, "Failed to enable USB phy\n");
185		goto fail_io;
186	}
187
188	/*
189	 * Workaround: reset of_node pointer to avoid conflict between legacy
190	 * Exynos OHCI port subnodes and generic USB device bindings
191	 */
192	exynos_ohci->of_node = pdev->dev.of_node;
193	if (exynos_ohci->legacy_phy)
194		pdev->dev.of_node = NULL;
195
196	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
197	if (err) {
198		dev_err(&pdev->dev, "Failed to add USB HCD\n");
199		goto fail_add_hcd;
200	}
201	device_wakeup_enable(hcd->self.controller);
202	return 0;
203
204fail_add_hcd:
205	exynos_ohci_phy_disable(&pdev->dev);
206	pdev->dev.of_node = exynos_ohci->of_node;
207fail_io:
208	clk_disable_unprepare(exynos_ohci->clk);
209fail_clk:
210	usb_put_hcd(hcd);
211	return err;
212}
213
214static int exynos_ohci_remove(struct platform_device *pdev)
215{
216	struct usb_hcd *hcd = platform_get_drvdata(pdev);
217	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
218
219	pdev->dev.of_node = exynos_ohci->of_node;
220
221	usb_remove_hcd(hcd);
222
223	exynos_ohci_phy_disable(&pdev->dev);
224
225	clk_disable_unprepare(exynos_ohci->clk);
226
227	usb_put_hcd(hcd);
228
229	return 0;
230}
231
232static void exynos_ohci_shutdown(struct platform_device *pdev)
233{
234	struct usb_hcd *hcd = platform_get_drvdata(pdev);
235
236	if (hcd->driver->shutdown)
237		hcd->driver->shutdown(hcd);
238}
239
240#ifdef CONFIG_PM
241static int exynos_ohci_suspend(struct device *dev)
242{
243	struct usb_hcd *hcd = dev_get_drvdata(dev);
244	struct exynos_ohci_hcd *exynos_ohci = to_exynos_ohci(hcd);
245	bool do_wakeup = device_may_wakeup(dev);
246	int rc = ohci_suspend(hcd, do_wakeup);
247
248	if (rc)
249		return rc;
250
251	exynos_ohci_phy_disable(dev);
252
253	clk_disable_unprepare(exynos_ohci->clk);
254
255	return 0;
256}
257
258static int exynos_ohci_resume(struct device *dev)
259{
260	struct usb_hcd *hcd			= dev_get_drvdata(dev);
261	struct exynos_ohci_hcd *exynos_ohci	= to_exynos_ohci(hcd);
262	int ret;
263
264	clk_prepare_enable(exynos_ohci->clk);
265
266	ret = exynos_ohci_phy_enable(dev);
267	if (ret) {
268		dev_err(dev, "Failed to enable USB phy\n");
269		clk_disable_unprepare(exynos_ohci->clk);
270		return ret;
271	}
272
273	ohci_resume(hcd, false);
274
275	return 0;
276}
277#else
278#define exynos_ohci_suspend	NULL
279#define exynos_ohci_resume	NULL
280#endif
281
282static const struct ohci_driver_overrides exynos_overrides __initconst = {
283	.extra_priv_size =	sizeof(struct exynos_ohci_hcd),
284};
285
286static const struct dev_pm_ops exynos_ohci_pm_ops = {
287	.suspend	= exynos_ohci_suspend,
288	.resume		= exynos_ohci_resume,
289};
290
291#ifdef CONFIG_OF
292static const struct of_device_id exynos_ohci_match[] = {
293	{ .compatible = "samsung,exynos4210-ohci" },
294	{},
295};
296MODULE_DEVICE_TABLE(of, exynos_ohci_match);
297#endif
298
299static struct platform_driver exynos_ohci_driver = {
300	.probe		= exynos_ohci_probe,
301	.remove		= exynos_ohci_remove,
302	.shutdown	= exynos_ohci_shutdown,
303	.driver = {
304		.name	= "exynos-ohci",
305		.pm	= &exynos_ohci_pm_ops,
306		.of_match_table	= of_match_ptr(exynos_ohci_match),
307	}
308};
309static int __init ohci_exynos_init(void)
310{
311	if (usb_disabled())
312		return -ENODEV;
313
314	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
315	ohci_init_driver(&exynos_ohci_hc_driver, &exynos_overrides);
316	return platform_driver_register(&exynos_ohci_driver);
317}
318module_init(ohci_exynos_init);
319
320static void __exit ohci_exynos_cleanup(void)
321{
322	platform_driver_unregister(&exynos_ohci_driver);
323}
324module_exit(ohci_exynos_cleanup);
325
326MODULE_ALIAS("platform:exynos-ohci");
327MODULE_AUTHOR("Jingoo Han <jg1.han@samsung.com>");
328MODULE_LICENSE("GPL v2");