1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * SAMSUNG EXYNOS USB HOST EHCI Controller
  4 *
  5 * Copyright (C) 2011 Samsung Electronics Co.Ltd
  6 * Author: Jingoo Han <jg1.han@samsung.com>
  7 * Author: Joonyoung Shim <jy0922.shim@samsung.com>
  8 */
  9
 10#include <linux/clk.h>
 11#include <linux/dma-mapping.h>
 12#include <linux/io.h>
 13#include <linux/kernel.h>
 14#include <linux/module.h>
 15#include <linux/of.h>
 16#include <linux/of_gpio.h>
 17#include <linux/phy/phy.h>
 18#include <linux/platform_device.h>
 19#include <linux/usb.h>
 20#include <linux/usb/hcd.h>
 21
 22#include "ehci.h"
 23
 24#define DRIVER_DESC "EHCI EXYNOS driver"
 25
 26#define EHCI_INSNREG00(base)			(base + 0x90)
 27#define EHCI_INSNREG00_ENA_INCR16		(0x1 << 25)
 28#define EHCI_INSNREG00_ENA_INCR8		(0x1 << 24)
 29#define EHCI_INSNREG00_ENA_INCR4		(0x1 << 23)
 30#define EHCI_INSNREG00_ENA_INCRX_ALIGN		(0x1 << 22)
 31#define EHCI_INSNREG00_ENABLE_DMA_BURST	\
 32	(EHCI_INSNREG00_ENA_INCR16 | EHCI_INSNREG00_ENA_INCR8 |	\
 33	 EHCI_INSNREG00_ENA_INCR4 | EHCI_INSNREG00_ENA_INCRX_ALIGN)
 34
 35static const char hcd_name[] = "ehci-exynos";
 36static struct hc_driver __read_mostly exynos_ehci_hc_driver;
 37
 38#define PHY_NUMBER 3
 39
 40struct exynos_ehci_hcd {
 41	struct clk *clk;
 42	struct phy *phy[PHY_NUMBER];
 43};
 44
 45#define to_exynos_ehci(hcd) (struct exynos_ehci_hcd *)(hcd_to_ehci(hcd)->priv)
 46
 47static int exynos_ehci_get_phy(struct device *dev,
 48				struct exynos_ehci_hcd *exynos_ehci)
 49{
 50	struct device_node *child;
 51	struct phy *phy;
 52	int phy_number;
 53	int ret;
 54
 55	/* Get PHYs for the controller */
 56	for_each_available_child_of_node(dev->of_node, child) {
 57		ret = of_property_read_u32(child, "reg", &phy_number);
 58		if (ret) {
 59			dev_err(dev, "Failed to parse device tree\n");
 60			of_node_put(child);
 61			return ret;
 62		}
 63
 64		if (phy_number >= PHY_NUMBER) {
 65			dev_err(dev, "Invalid number of PHYs\n");
 66			of_node_put(child);
 67			return -EINVAL;
 68		}
 69
 70		phy = devm_of_phy_get(dev, child, NULL);
 71		exynos_ehci->phy[phy_number] = phy;
 72		if (IS_ERR(phy)) {
 73			ret = PTR_ERR(phy);
 74			if (ret == -EPROBE_DEFER) {
 75				of_node_put(child);
 76				return ret;
 77			} else if (ret != -ENOSYS && ret != -ENODEV) {
 78				dev_err(dev,
 79					"Error retrieving usb2 phy: %d\n", ret);
 80				of_node_put(child);
 81				return ret;
 82			}
 83		}
 84	}
 85
 86	return 0;
 87}
 88
 89static int exynos_ehci_phy_enable(struct device *dev)
 90{
 91	struct usb_hcd *hcd = dev_get_drvdata(dev);
 92	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
 93	int i;
 94	int ret = 0;
 95
 96	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
 97		if (!IS_ERR(exynos_ehci->phy[i]))
 98			ret = phy_power_on(exynos_ehci->phy[i]);
 99	if (ret)
100		for (i--; i >= 0; i--)
101			if (!IS_ERR(exynos_ehci->phy[i]))
102				phy_power_off(exynos_ehci->phy[i]);
103
104	return ret;
105}
106
107static void exynos_ehci_phy_disable(struct device *dev)
108{
109	struct usb_hcd *hcd = dev_get_drvdata(dev);
110	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
111	int i;
112
113	for (i = 0; i < PHY_NUMBER; i++)
114		if (!IS_ERR(exynos_ehci->phy[i]))
115			phy_power_off(exynos_ehci->phy[i]);
116}
117
118static void exynos_setup_vbus_gpio(struct device *dev)
119{
120	int err;
121	int gpio;
122
123	if (!dev->of_node)
124		return;
125
126	gpio = of_get_named_gpio(dev->of_node, "samsung,vbus-gpio", 0);
127	if (!gpio_is_valid(gpio))
128		return;
129
130	err = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH,
131				    "ehci_vbus_gpio");
132	if (err)
133		dev_err(dev, "can't request ehci vbus gpio %d", gpio);
134}
135
136static int exynos_ehci_probe(struct platform_device *pdev)
137{
138	struct exynos_ehci_hcd *exynos_ehci;
139	struct usb_hcd *hcd;
140	struct ehci_hcd *ehci;
141	struct resource *res;
142	int irq;
143	int err;
144
145	/*
146	 * Right now device-tree probed devices don't get dma_mask set.
147	 * Since shared usb code relies on it, set it here for now.
148	 * Once we move to full device tree support this will vanish off.
149	 */
150	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
151	if (err)
152		return err;
153
154	exynos_setup_vbus_gpio(&pdev->dev);
155
156	hcd = usb_create_hcd(&exynos_ehci_hc_driver,
157			     &pdev->dev, dev_name(&pdev->dev));
158	if (!hcd) {
159		dev_err(&pdev->dev, "Unable to create HCD\n");
160		return -ENOMEM;
161	}
162	exynos_ehci = to_exynos_ehci(hcd);
163
164	if (of_device_is_compatible(pdev->dev.of_node,
165					"samsung,exynos5440-ehci"))
166		goto skip_phy;
167
168	err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci);
169	if (err)
170		goto fail_clk;
171
172skip_phy:
173
174	exynos_ehci->clk = devm_clk_get(&pdev->dev, "usbhost");
175
176	if (IS_ERR(exynos_ehci->clk)) {
177		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
178		err = PTR_ERR(exynos_ehci->clk);
179		goto fail_clk;
180	}
181
182	err = clk_prepare_enable(exynos_ehci->clk);
183	if (err)
184		goto fail_clk;
185
186	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
187	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
188	if (IS_ERR(hcd->regs)) {
189		err = PTR_ERR(hcd->regs);
190		goto fail_io;
191	}
192
193	hcd->rsrc_start = res->start;
194	hcd->rsrc_len = resource_size(res);
195
196	irq = platform_get_irq(pdev, 0);
197	if (!irq) {
198		dev_err(&pdev->dev, "Failed to get IRQ\n");
199		err = -ENODEV;
200		goto fail_io;
201	}
202
203	err = exynos_ehci_phy_enable(&pdev->dev);
204	if (err) {
205		dev_err(&pdev->dev, "Failed to enable USB phy\n");
206		goto fail_io;
207	}
208
209	ehci = hcd_to_ehci(hcd);
210	ehci->caps = hcd->regs;
211
212	/* DMA burst Enable */
213	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
214
215	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
216	if (err) {
217		dev_err(&pdev->dev, "Failed to add USB HCD\n");
218		goto fail_add_hcd;
219	}
220	device_wakeup_enable(hcd->self.controller);
221
222	platform_set_drvdata(pdev, hcd);
223
224	return 0;
225
226fail_add_hcd:
227	exynos_ehci_phy_disable(&pdev->dev);
228fail_io:
229	clk_disable_unprepare(exynos_ehci->clk);
230fail_clk:
231	usb_put_hcd(hcd);
232	return err;
233}
234
235static int exynos_ehci_remove(struct platform_device *pdev)
236{
237	struct usb_hcd *hcd = platform_get_drvdata(pdev);
238	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
239
240	usb_remove_hcd(hcd);
241
242	exynos_ehci_phy_disable(&pdev->dev);
243
244	clk_disable_unprepare(exynos_ehci->clk);
245
246	usb_put_hcd(hcd);
247
248	return 0;
249}
250
251#ifdef CONFIG_PM
252static int exynos_ehci_suspend(struct device *dev)
253{
254	struct usb_hcd *hcd = dev_get_drvdata(dev);
255	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
256
257	bool do_wakeup = device_may_wakeup(dev);
258	int rc;
259
260	rc = ehci_suspend(hcd, do_wakeup);
261	if (rc)
262		return rc;
263
264	exynos_ehci_phy_disable(dev);
265
266	clk_disable_unprepare(exynos_ehci->clk);
267
268	return rc;
269}
270
271static int exynos_ehci_resume(struct device *dev)
272{
273	struct usb_hcd *hcd = dev_get_drvdata(dev);
274	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
275	int ret;
276
277	ret = clk_prepare_enable(exynos_ehci->clk);
278	if (ret)
279		return ret;
280
281	ret = exynos_ehci_phy_enable(dev);
282	if (ret) {
283		dev_err(dev, "Failed to enable USB phy\n");
284		clk_disable_unprepare(exynos_ehci->clk);
285		return ret;
286	}
287
288	/* DMA burst Enable */
289	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
290
291	ehci_resume(hcd, false);
292	return 0;
293}
294#else
295#define exynos_ehci_suspend	NULL
296#define exynos_ehci_resume	NULL
297#endif
298
299static const struct dev_pm_ops exynos_ehci_pm_ops = {
300	.suspend	= exynos_ehci_suspend,
301	.resume		= exynos_ehci_resume,
302};
303
304#ifdef CONFIG_OF
305static const struct of_device_id exynos_ehci_match[] = {
306	{ .compatible = "samsung,exynos4210-ehci" },
307	{ .compatible = "samsung,exynos5440-ehci" },
308	{},
309};
310MODULE_DEVICE_TABLE(of, exynos_ehci_match);
311#endif
312
313static struct platform_driver exynos_ehci_driver = {
314	.probe		= exynos_ehci_probe,
315	.remove		= exynos_ehci_remove,
316	.shutdown	= usb_hcd_platform_shutdown,
317	.driver = {
318		.name	= "exynos-ehci",
319		.pm	= &exynos_ehci_pm_ops,
320		.of_match_table = of_match_ptr(exynos_ehci_match),
321	}
322};
323static const struct ehci_driver_overrides exynos_overrides __initconst = {
324	.extra_priv_size = sizeof(struct exynos_ehci_hcd),
325};
326
327static int __init ehci_exynos_init(void)
328{
329	if (usb_disabled())
330		return -ENODEV;
331
332	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
333	ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides);
334	return platform_driver_register(&exynos_ehci_driver);
335}
336module_init(ehci_exynos_init);
337
338static void __exit ehci_exynos_cleanup(void)
339{
340	platform_driver_unregister(&exynos_ehci_driver);
341}
342module_exit(ehci_exynos_cleanup);
343
344MODULE_DESCRIPTION(DRIVER_DESC);
345MODULE_ALIAS("platform:exynos-ehci");
346MODULE_AUTHOR("Jingoo Han");
347MODULE_AUTHOR("Joonyoung Shim");
348MODULE_LICENSE("GPL v2");