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
 40static const char hcd_name[] = "ehci-exynos";
 41static struct hc_driver __read_mostly exynos_ehci_hc_driver;
 42
 43#define PHY_NUMBER 3
 44
 45struct 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
 52static 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		if (IS_ERR(phy)) {
 78			ret = PTR_ERR(phy);
 79			if (ret == -EPROBE_DEFER) {
 80				return ret;
 81			} else if (ret != -ENOSYS && ret != -ENODEV) {
 82				dev_err(dev,
 83					"Error retrieving usb2 phy: %d\n", ret);
 84				return ret;
 85			}
 86		}
 87	}
 88
 89	return 0;
 90}
 91
 92static int exynos_ehci_phy_enable(struct device *dev)
 93{
 94	struct usb_hcd *hcd = dev_get_drvdata(dev);
 95	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
 96	int i;
 97	int ret = 0;
 98
 99	for (i = 0; ret == 0 && i < PHY_NUMBER; i++)
100		if (!IS_ERR(exynos_ehci->phy[i]))
101			ret = phy_power_on(exynos_ehci->phy[i]);
102	if (ret)
103		for (i--; i >= 0; i--)
104			if (!IS_ERR(exynos_ehci->phy[i]))
105				phy_power_off(exynos_ehci->phy[i]);
106
107	return ret;
108}
109
110static void exynos_ehci_phy_disable(struct device *dev)
111{
112	struct usb_hcd *hcd = dev_get_drvdata(dev);
113	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
114	int i;
115
116	for (i = 0; i < PHY_NUMBER; i++)
117		if (!IS_ERR(exynos_ehci->phy[i]))
118			phy_power_off(exynos_ehci->phy[i]);
119}
120
121static void exynos_setup_vbus_gpio(struct device *dev)
122{
123	int err;
124	int gpio;
125
126	if (!dev->of_node)
127		return;
128
129	gpio = of_get_named_gpio(dev->of_node, "samsung,vbus-gpio", 0);
130	if (!gpio_is_valid(gpio))
131		return;
132
133	err = devm_gpio_request_one(dev, gpio, GPIOF_OUT_INIT_HIGH,
134				    "ehci_vbus_gpio");
135	if (err)
136		dev_err(dev, "can't request ehci vbus gpio %d", gpio);
137}
138
139static int exynos_ehci_probe(struct platform_device *pdev)
140{
141	struct exynos_ehci_hcd *exynos_ehci;
142	struct usb_hcd *hcd;
143	struct ehci_hcd *ehci;
144	struct resource *res;
145	int irq;
146	int err;
147
148	/*
149	 * Right now device-tree probed devices don't get dma_mask set.
150	 * Since shared usb code relies on it, set it here for now.
151	 * Once we move to full device tree support this will vanish off.
152	 */
153	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
154	if (err)
155		return err;
156
157	exynos_setup_vbus_gpio(&pdev->dev);
158
159	hcd = usb_create_hcd(&exynos_ehci_hc_driver,
160			     &pdev->dev, dev_name(&pdev->dev));
161	if (!hcd) {
162		dev_err(&pdev->dev, "Unable to create HCD\n");
163		return -ENOMEM;
164	}
165	exynos_ehci = to_exynos_ehci(hcd);
166
167	if (of_device_is_compatible(pdev->dev.of_node,
168					"samsung,exynos5440-ehci"))
169		goto skip_phy;
170
171	err = exynos_ehci_get_phy(&pdev->dev, exynos_ehci);
172	if (err)
173		goto fail_clk;
174
175skip_phy:
176
177	exynos_ehci->clk = devm_clk_get(&pdev->dev, "usbhost");
178
179	if (IS_ERR(exynos_ehci->clk)) {
180		dev_err(&pdev->dev, "Failed to get usbhost clock\n");
181		err = PTR_ERR(exynos_ehci->clk);
182		goto fail_clk;
183	}
184
185	err = clk_prepare_enable(exynos_ehci->clk);
186	if (err)
187		goto fail_clk;
188
189	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
190	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
191	if (IS_ERR(hcd->regs)) {
192		err = PTR_ERR(hcd->regs);
193		goto fail_io;
194	}
195
196	hcd->rsrc_start = res->start;
197	hcd->rsrc_len = resource_size(res);
198
199	irq = platform_get_irq(pdev, 0);
200	if (!irq) {
201		dev_err(&pdev->dev, "Failed to get IRQ\n");
202		err = -ENODEV;
203		goto fail_io;
204	}
205
206	err = exynos_ehci_phy_enable(&pdev->dev);
207	if (err) {
208		dev_err(&pdev->dev, "Failed to enable USB phy\n");
209		goto fail_io;
210	}
211
212	ehci = hcd_to_ehci(hcd);
213	ehci->caps = hcd->regs;
214
215	/* DMA burst Enable */
216	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
217
218	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
219	if (err) {
220		dev_err(&pdev->dev, "Failed to add USB HCD\n");
221		goto fail_add_hcd;
222	}
223	device_wakeup_enable(hcd->self.controller);
224
225	platform_set_drvdata(pdev, hcd);
226
227	return 0;
228
229fail_add_hcd:
230	exynos_ehci_phy_disable(&pdev->dev);
231fail_io:
232	clk_disable_unprepare(exynos_ehci->clk);
233fail_clk:
234	usb_put_hcd(hcd);
235	return err;
236}
237
238static int exynos_ehci_remove(struct platform_device *pdev)
239{
240	struct usb_hcd *hcd = platform_get_drvdata(pdev);
241	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
242
243	usb_remove_hcd(hcd);
244
245	exynos_ehci_phy_disable(&pdev->dev);
246
247	clk_disable_unprepare(exynos_ehci->clk);
248
249	usb_put_hcd(hcd);
250
251	return 0;
252}
253
254#ifdef CONFIG_PM
255static int exynos_ehci_suspend(struct device *dev)
256{
257	struct usb_hcd *hcd = dev_get_drvdata(dev);
258	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
259
260	bool do_wakeup = device_may_wakeup(dev);
261	int rc;
262
263	rc = ehci_suspend(hcd, do_wakeup);
264	if (rc)
265		return rc;
266
267	exynos_ehci_phy_disable(dev);
268
269	clk_disable_unprepare(exynos_ehci->clk);
270
271	return rc;
272}
273
274static int exynos_ehci_resume(struct device *dev)
275{
276	struct usb_hcd *hcd = dev_get_drvdata(dev);
277	struct exynos_ehci_hcd *exynos_ehci = to_exynos_ehci(hcd);
278	int ret;
279
280	clk_prepare_enable(exynos_ehci->clk);
281
282	ret = exynos_ehci_phy_enable(dev);
283	if (ret) {
284		dev_err(dev, "Failed to enable USB phy\n");
285		clk_disable_unprepare(exynos_ehci->clk);
286		return ret;
287	}
288
289	/* DMA burst Enable */
290	writel(EHCI_INSNREG00_ENABLE_DMA_BURST, EHCI_INSNREG00(hcd->regs));
291
292	ehci_resume(hcd, false);
293	return 0;
294}
295#else
296#define exynos_ehci_suspend	NULL
297#define exynos_ehci_resume	NULL
298#endif
299
300static const struct dev_pm_ops exynos_ehci_pm_ops = {
301	.suspend	= exynos_ehci_suspend,
302	.resume		= exynos_ehci_resume,
303};
304
305#ifdef CONFIG_OF
306static const struct of_device_id exynos_ehci_match[] = {
307	{ .compatible = "samsung,exynos4210-ehci" },
308	{ .compatible = "samsung,exynos5440-ehci" },
309	{},
310};
311MODULE_DEVICE_TABLE(of, exynos_ehci_match);
312#endif
313
314static struct platform_driver exynos_ehci_driver = {
315	.probe		= exynos_ehci_probe,
316	.remove		= exynos_ehci_remove,
317	.shutdown	= usb_hcd_platform_shutdown,
318	.driver = {
319		.name	= "exynos-ehci",
320		.pm	= &exynos_ehci_pm_ops,
321		.of_match_table = of_match_ptr(exynos_ehci_match),
322	}
323};
324static const struct ehci_driver_overrides exynos_overrides __initdata = {
325	.extra_priv_size = sizeof(struct exynos_ehci_hcd),
326};
327
328static int __init ehci_exynos_init(void)
329{
330	if (usb_disabled())
331		return -ENODEV;
332
333	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
334	ehci_init_driver(&exynos_ehci_hc_driver, &exynos_overrides);
335	return platform_driver_register(&exynos_ehci_driver);
336}
337module_init(ehci_exynos_init);
338
339static void __exit ehci_exynos_cleanup(void)
340{
341	platform_driver_unregister(&exynos_ehci_driver);
342}
343module_exit(ehci_exynos_cleanup);
344
345MODULE_DESCRIPTION(DRIVER_DESC);
346MODULE_ALIAS("platform:exynos-ehci");
347MODULE_AUTHOR("Jingoo Han");
348MODULE_AUTHOR("Joonyoung Shim");
349MODULE_LICENSE("GPL v2");