[go: nahoru, domu]
1/*
2 * Driver for EHCI UHP on Atmel chips
3 *
4 *  Copyright (C) 2009 Atmel Corporation,
5 *                     Nicolas Ferre <nicolas.ferre@atmel.com>
6 *
7 *  Based on various ehci-*.c drivers
8 *
9 * This file is subject to the terms and conditions of the GNU General Public
10 * License.  See the file COPYING in the main directory of this archive for
11 * more details.
12 */
13
14#include <linux/clk.h>
15#include <linux/dma-mapping.h>
16#include <linux/io.h>
17#include <linux/kernel.h>
18#include <linux/module.h>
19#include <linux/of.h>
20#include <linux/of_platform.h>
21#include <linux/platform_device.h>
22#include <linux/usb.h>
23#include <linux/usb/hcd.h>
24
25#include "ehci.h"
26
27#define DRIVER_DESC "EHCI Atmel driver"
28
29static const char hcd_name[] = "ehci-atmel";
30static struct hc_driver __read_mostly ehci_atmel_hc_driver;
31
32/* interface and function clocks */
33static struct clk *iclk, *fclk, *uclk;
34static int clocked;
35
36/*-------------------------------------------------------------------------*/
37
38static void atmel_start_clock(void)
39{
40	if (IS_ENABLED(CONFIG_COMMON_CLK)) {
41		clk_set_rate(uclk, 48000000);
42		clk_prepare_enable(uclk);
43	}
44	clk_prepare_enable(iclk);
45	clk_prepare_enable(fclk);
46	clocked = 1;
47}
48
49static void atmel_stop_clock(void)
50{
51	clk_disable_unprepare(fclk);
52	clk_disable_unprepare(iclk);
53	if (IS_ENABLED(CONFIG_COMMON_CLK))
54		clk_disable_unprepare(uclk);
55	clocked = 0;
56}
57
58static void atmel_start_ehci(struct platform_device *pdev)
59{
60	dev_dbg(&pdev->dev, "start\n");
61	atmel_start_clock();
62}
63
64static void atmel_stop_ehci(struct platform_device *pdev)
65{
66	dev_dbg(&pdev->dev, "stop\n");
67	atmel_stop_clock();
68}
69
70/*-------------------------------------------------------------------------*/
71
72static int ehci_atmel_drv_probe(struct platform_device *pdev)
73{
74	struct usb_hcd *hcd;
75	const struct hc_driver *driver = &ehci_atmel_hc_driver;
76	struct resource *res;
77	struct ehci_hcd *ehci;
78	int irq;
79	int retval;
80
81	if (usb_disabled())
82		return -ENODEV;
83
84	pr_debug("Initializing Atmel-SoC USB Host Controller\n");
85
86	irq = platform_get_irq(pdev, 0);
87	if (irq <= 0) {
88		dev_err(&pdev->dev,
89			"Found HC with no IRQ. Check %s setup!\n",
90			dev_name(&pdev->dev));
91		retval = -ENODEV;
92		goto fail_create_hcd;
93	}
94
95	/* Right now device-tree probed devices don't get dma_mask set.
96	 * Since shared usb code relies on it, set it here for now.
97	 * Once we have dma capability bindings this can go away.
98	 */
99	retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
100	if (retval)
101		goto fail_create_hcd;
102
103	hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev));
104	if (!hcd) {
105		retval = -ENOMEM;
106		goto fail_create_hcd;
107	}
108
109	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
110	if (!res) {
111		dev_err(&pdev->dev,
112			"Found HC with no register addr. Check %s setup!\n",
113			dev_name(&pdev->dev));
114		retval = -ENODEV;
115		goto fail_request_resource;
116	}
117	hcd->rsrc_start = res->start;
118	hcd->rsrc_len = resource_size(res);
119
120	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
121	if (IS_ERR(hcd->regs)) {
122		retval = PTR_ERR(hcd->regs);
123		goto fail_request_resource;
124	}
125
126	iclk = devm_clk_get(&pdev->dev, "ehci_clk");
127	if (IS_ERR(iclk)) {
128		dev_err(&pdev->dev, "Error getting interface clock\n");
129		retval = -ENOENT;
130		goto fail_request_resource;
131	}
132	fclk = devm_clk_get(&pdev->dev, "uhpck");
133	if (IS_ERR(fclk)) {
134		dev_err(&pdev->dev, "Error getting function clock\n");
135		retval = -ENOENT;
136		goto fail_request_resource;
137	}
138	if (IS_ENABLED(CONFIG_COMMON_CLK)) {
139		uclk = devm_clk_get(&pdev->dev, "usb_clk");
140		if (IS_ERR(uclk)) {
141			dev_err(&pdev->dev, "failed to get uclk\n");
142			retval = PTR_ERR(uclk);
143			goto fail_request_resource;
144		}
145	}
146
147	ehci = hcd_to_ehci(hcd);
148	/* registers start at offset 0x0 */
149	ehci->caps = hcd->regs;
150
151	atmel_start_ehci(pdev);
152
153	retval = usb_add_hcd(hcd, irq, IRQF_SHARED);
154	if (retval)
155		goto fail_add_hcd;
156	device_wakeup_enable(hcd->self.controller);
157
158	return retval;
159
160fail_add_hcd:
161	atmel_stop_ehci(pdev);
162fail_request_resource:
163	usb_put_hcd(hcd);
164fail_create_hcd:
165	dev_err(&pdev->dev, "init %s fail, %d\n",
166		dev_name(&pdev->dev), retval);
167
168	return retval;
169}
170
171static int ehci_atmel_drv_remove(struct platform_device *pdev)
172{
173	struct usb_hcd *hcd = platform_get_drvdata(pdev);
174
175	usb_remove_hcd(hcd);
176	usb_put_hcd(hcd);
177
178	atmel_stop_ehci(pdev);
179	fclk = iclk = NULL;
180
181	return 0;
182}
183
184#ifdef CONFIG_OF
185static const struct of_device_id atmel_ehci_dt_ids[] = {
186	{ .compatible = "atmel,at91sam9g45-ehci" },
187	{ /* sentinel */ }
188};
189
190MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids);
191#endif
192
193static struct platform_driver ehci_atmel_driver = {
194	.probe		= ehci_atmel_drv_probe,
195	.remove		= ehci_atmel_drv_remove,
196	.shutdown	= usb_hcd_platform_shutdown,
197	.driver		= {
198		.name	= "atmel-ehci",
199		.of_match_table	= of_match_ptr(atmel_ehci_dt_ids),
200	},
201};
202
203static int __init ehci_atmel_init(void)
204{
205	if (usb_disabled())
206		return -ENODEV;
207
208	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
209	ehci_init_driver(&ehci_atmel_hc_driver, NULL);
210	return platform_driver_register(&ehci_atmel_driver);
211}
212module_init(ehci_atmel_init);
213
214static void __exit ehci_atmel_cleanup(void)
215{
216	platform_driver_unregister(&ehci_atmel_driver);
217}
218module_exit(ehci_atmel_cleanup);
219
220MODULE_DESCRIPTION(DRIVER_DESC);
221MODULE_ALIAS("platform:atmel-ehci");
222MODULE_AUTHOR("Nicolas Ferre");
223MODULE_LICENSE("GPL");
224