1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Driver for EHCI UHP on Atmel chips
4 *
5 *  Copyright (C) 2009 Atmel Corporation,
6 *                     Nicolas Ferre <nicolas.ferre@atmel.com>
7 *
8 *  Based on various ehci-*.c drivers
9 */
10
11#include <linux/clk.h>
12#include <linux/dma-mapping.h>
13#include <linux/io.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/of_platform.h>
18#include <linux/platform_device.h>
19#include <linux/usb.h>
20#include <linux/usb/hcd.h>
21#include <linux/usb/phy.h>
22#include <linux/usb/of.h>
23
24#include "ehci.h"
25
26#define DRIVER_DESC "EHCI Atmel driver"
27
28#define EHCI_INSNREG(index)			((index) * 4 + 0x90)
29#define EHCI_INSNREG08_HSIC_EN			BIT(2)
30
31/* interface and function clocks */
32#define hcd_to_atmel_ehci_priv(h) \
33	((struct atmel_ehci_priv *)hcd_to_ehci(h)->priv)
34
35struct atmel_ehci_priv {
36	struct clk *iclk;
37	struct clk *uclk;
38	bool clocked;
39};
40
41static struct hc_driver __read_mostly ehci_atmel_hc_driver;
42
43static const struct ehci_driver_overrides ehci_atmel_drv_overrides __initconst = {
44	.extra_priv_size = sizeof(struct atmel_ehci_priv),
45};
46
47/*-------------------------------------------------------------------------*/
48
49static void atmel_start_clock(struct atmel_ehci_priv *atmel_ehci)
50{
51	if (atmel_ehci->clocked)
52		return;
53
54	clk_prepare_enable(atmel_ehci->uclk);
55	clk_prepare_enable(atmel_ehci->iclk);
56	atmel_ehci->clocked = true;
57}
58
59static void atmel_stop_clock(struct atmel_ehci_priv *atmel_ehci)
60{
61	if (!atmel_ehci->clocked)
62		return;
63
64	clk_disable_unprepare(atmel_ehci->iclk);
65	clk_disable_unprepare(atmel_ehci->uclk);
66	atmel_ehci->clocked = false;
67}
68
69static void atmel_start_ehci(struct platform_device *pdev)
70{
71	struct usb_hcd *hcd = platform_get_drvdata(pdev);
72	struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
73
74	dev_dbg(&pdev->dev, "start\n");
75	atmel_start_clock(atmel_ehci);
76}
77
78static void atmel_stop_ehci(struct platform_device *pdev)
79{
80	struct usb_hcd *hcd = platform_get_drvdata(pdev);
81	struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
82
83	dev_dbg(&pdev->dev, "stop\n");
84	atmel_stop_clock(atmel_ehci);
85}
86
87/*-------------------------------------------------------------------------*/
88
89static int ehci_atmel_drv_probe(struct platform_device *pdev)
90{
91	struct usb_hcd *hcd;
92	const struct hc_driver *driver = &ehci_atmel_hc_driver;
93	struct resource *res;
94	struct ehci_hcd *ehci;
95	struct atmel_ehci_priv *atmel_ehci;
96	int irq;
97	int retval;
98
99	if (usb_disabled())
100		return -ENODEV;
101
102	pr_debug("Initializing Atmel-SoC USB Host Controller\n");
103
104	irq = platform_get_irq(pdev, 0);
105	if (irq < 0) {
106		retval = irq;
107		goto fail_create_hcd;
108	}
109
110	/* Right now device-tree probed devices don't get dma_mask set.
111	 * Since shared usb code relies on it, set it here for now.
112	 * Once we have dma capability bindings this can go away.
113	 */
114	retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
115	if (retval)
116		goto fail_create_hcd;
117
118	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
119	if (!hcd) {
120		retval = -ENOMEM;
121		goto fail_create_hcd;
122	}
123	atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
124
125	hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
126	if (IS_ERR(hcd->regs)) {
127		retval = PTR_ERR(hcd->regs);
128		goto fail_request_resource;
129	}
130
131	hcd->rsrc_start = res->start;
132	hcd->rsrc_len = resource_size(res);
133
134	atmel_ehci->iclk = devm_clk_get(&pdev->dev, "ehci_clk");
135	if (IS_ERR(atmel_ehci->iclk)) {
136		dev_err(&pdev->dev, "Error getting interface clock\n");
137		retval = -ENOENT;
138		goto fail_request_resource;
139	}
140
141	atmel_ehci->uclk = devm_clk_get(&pdev->dev, "usb_clk");
142	if (IS_ERR(atmel_ehci->uclk)) {
143		dev_err(&pdev->dev, "failed to get uclk\n");
144		retval = PTR_ERR(atmel_ehci->uclk);
145		goto fail_request_resource;
146	}
147
148	ehci = hcd_to_ehci(hcd);
149	/* registers start at offset 0x0 */
150	ehci->caps = hcd->regs;
151
152	atmel_start_ehci(pdev);
153
154	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
155	if (retval)
156		goto fail_add_hcd;
157	device_wakeup_enable(hcd->self.controller);
158
159	if (of_usb_get_phy_mode(pdev->dev.of_node) == USBPHY_INTERFACE_MODE_HSIC)
160		writel(EHCI_INSNREG08_HSIC_EN, hcd->regs + EHCI_INSNREG(8));
161
162	return retval;
163
164fail_add_hcd:
165	atmel_stop_ehci(pdev);
166fail_request_resource:
167	usb_put_hcd(hcd);
168fail_create_hcd:
169	dev_err(&pdev->dev, "init %s fail, %d\n",
170		dev_name(&pdev->dev), retval);
171
172	return retval;
173}
174
175static void ehci_atmel_drv_remove(struct platform_device *pdev)
176{
177	struct usb_hcd *hcd = platform_get_drvdata(pdev);
178
179	usb_remove_hcd(hcd);
180	usb_put_hcd(hcd);
181
182	atmel_stop_ehci(pdev);
183}
184
185static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev)
186{
187	struct usb_hcd *hcd = dev_get_drvdata(dev);
188	struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
189	int ret;
190
191	ret = ehci_suspend(hcd, false);
192	if (ret)
193		return ret;
194
195	atmel_stop_clock(atmel_ehci);
196	return 0;
197}
198
199static int __maybe_unused ehci_atmel_drv_resume(struct device *dev)
200{
201	struct usb_hcd *hcd = dev_get_drvdata(dev);
202	struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd);
203
204	atmel_start_clock(atmel_ehci);
205	ehci_resume(hcd, false);
206	return 0;
207}
208
209#ifdef CONFIG_OF
210static const struct of_device_id atmel_ehci_dt_ids[] = {
211	{ .compatible = "atmel,at91sam9g45-ehci" },
212	{ /* sentinel */ }
213};
214
215MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
216#endif
217
218static SIMPLE_DEV_PM_OPS(ehci_atmel_pm_ops, ehci_atmel_drv_suspend,
219					ehci_atmel_drv_resume);
220
221static struct platform_driver ehci_atmel_driver = {
222	.probe		= ehci_atmel_drv_probe,
223	.remove_new	= ehci_atmel_drv_remove,
224	.shutdown	= usb_hcd_platform_shutdown,
225	.driver		= {
226		.name	= "atmel-ehci",
227		.pm	= &ehci_atmel_pm_ops,
228		.of_match_table	= of_match_ptr(atmel_ehci_dt_ids),
229	},
230};
231
232static int __init ehci_atmel_init(void)
233{
234	if (usb_disabled())
235		return -ENODEV;
236
237	ehci_init_driver(&ehci_atmel_hc_driver, &ehci_atmel_drv_overrides);
238	return platform_driver_register(&ehci_atmel_driver);
239}
240module_init(ehci_atmel_init);
241
242static void __exit ehci_atmel_cleanup(void)
243{
244	platform_driver_unregister(&ehci_atmel_driver);
245}
246module_exit(ehci_atmel_cleanup);
247
248MODULE_DESCRIPTION(DRIVER_DESC);
249MODULE_ALIAS("platform:atmel-ehci");
250MODULE_AUTHOR("Nicolas Ferre");
251MODULE_LICENSE("GPL");
252