[go: nahoru, domu]

1/*
2 * ST EHCI driver
3 *
4 * Copyright (C) 2014 STMicroelectronics – All Rights Reserved
5 *
6 * Author: Peter Griffin <peter.griffin@linaro.org>
7 *
8 * Derived from ehci-platform.c
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 */
14
15#include <linux/clk.h>
16#include <linux/dma-mapping.h>
17#include <linux/err.h>
18#include <linux/kernel.h>
19#include <linux/hrtimer.h>
20#include <linux/io.h>
21#include <linux/module.h>
22#include <linux/of.h>
23#include <linux/phy/phy.h>
24#include <linux/platform_device.h>
25#include <linux/reset.h>
26#include <linux/usb.h>
27#include <linux/usb/hcd.h>
28#include <linux/usb/ehci_pdriver.h>
29
30#include "ehci.h"
31
32#define USB_MAX_CLKS 3
33
34struct st_ehci_platform_priv {
35	struct clk *clks[USB_MAX_CLKS];
36	struct clk *clk48;
37	struct reset_control *rst;
38	struct reset_control *pwr;
39	struct phy *phy;
40};
41
42#define DRIVER_DESC "EHCI STMicroelectronics driver"
43
44#define hcd_to_ehci_priv(h) \
45	((struct st_ehci_platform_priv *)hcd_to_ehci(h)->priv)
46
47static const char hcd_name[] = "ehci-st";
48
49#define EHCI_CAPS_SIZE 0x10
50#define AHB2STBUS_INSREG01 (EHCI_CAPS_SIZE + 0x84)
51
52static int st_ehci_platform_reset(struct usb_hcd *hcd)
53{
54	struct platform_device *pdev = to_platform_device(hcd->self.controller);
55	struct usb_ehci_pdata *pdata = dev_get_platdata(&pdev->dev);
56	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
57	int retval;
58	u32 threshold;
59
60	/* Set EHCI packet buffer IN/OUT threshold to 128 bytes */
61	threshold = 128 | (128 << 16);
62	writel(threshold, hcd->regs + AHB2STBUS_INSREG01);
63
64	ehci->caps = hcd->regs + pdata->caps_offset;
65	retval = ehci_setup(hcd);
66	if (retval)
67		return retval;
68
69	return 0;
70}
71
72static int st_ehci_platform_power_on(struct platform_device *dev)
73{
74	struct usb_hcd *hcd = platform_get_drvdata(dev);
75	struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
76	int clk, ret;
77
78	ret = reset_control_deassert(priv->pwr);
79	if (ret)
80		return ret;
81
82	ret = reset_control_deassert(priv->rst);
83	if (ret)
84		goto err_assert_power;
85
86	/* some SoCs don't have a dedicated 48Mhz clock, but those that do
87	   need the rate to be explicitly set */
88	if (priv->clk48) {
89		ret = clk_set_rate(priv->clk48, 48000000);
90		if (ret)
91			goto err_assert_reset;
92	}
93
94	for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++) {
95		ret = clk_prepare_enable(priv->clks[clk]);
96		if (ret)
97			goto err_disable_clks;
98	}
99
100	ret = phy_init(priv->phy);
101	if (ret)
102		goto err_disable_clks;
103
104	ret = phy_power_on(priv->phy);
105	if (ret)
106		goto err_exit_phy;
107
108	return 0;
109
110err_exit_phy:
111	phy_exit(priv->phy);
112err_disable_clks:
113	while (--clk >= 0)
114		clk_disable_unprepare(priv->clks[clk]);
115err_assert_reset:
116	reset_control_assert(priv->rst);
117err_assert_power:
118	reset_control_assert(priv->pwr);
119
120	return ret;
121}
122
123static void st_ehci_platform_power_off(struct platform_device *dev)
124{
125	struct usb_hcd *hcd = platform_get_drvdata(dev);
126	struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
127	int clk;
128
129	reset_control_assert(priv->pwr);
130
131	reset_control_assert(priv->rst);
132
133	phy_power_off(priv->phy);
134
135	phy_exit(priv->phy);
136
137	for (clk = USB_MAX_CLKS - 1; clk >= 0; clk--)
138		if (priv->clks[clk])
139			clk_disable_unprepare(priv->clks[clk]);
140
141}
142
143static struct hc_driver __read_mostly ehci_platform_hc_driver;
144
145static const struct ehci_driver_overrides platform_overrides __initconst = {
146	.reset =		st_ehci_platform_reset,
147	.extra_priv_size =	sizeof(struct st_ehci_platform_priv),
148};
149
150static struct usb_ehci_pdata ehci_platform_defaults = {
151	.power_on =		st_ehci_platform_power_on,
152	.power_suspend =	st_ehci_platform_power_off,
153	.power_off =		st_ehci_platform_power_off,
154};
155
156static int st_ehci_platform_probe(struct platform_device *dev)
157{
158	struct usb_hcd *hcd;
159	struct resource *res_mem;
160	struct usb_ehci_pdata *pdata = &ehci_platform_defaults;
161	struct st_ehci_platform_priv *priv;
162	struct ehci_hcd *ehci;
163	int err, irq, clk = 0;
164
165	if (usb_disabled())
166		return -ENODEV;
167
168	irq = platform_get_irq(dev, 0);
169	if (irq < 0) {
170		dev_err(&dev->dev, "no irq provided");
171		return irq;
172	}
173	res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
174	if (!res_mem) {
175		dev_err(&dev->dev, "no memory resource provided");
176		return -ENXIO;
177	}
178
179	hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev,
180			     dev_name(&dev->dev));
181	if (!hcd)
182		return -ENOMEM;
183
184	platform_set_drvdata(dev, hcd);
185	dev->dev.platform_data = pdata;
186	priv = hcd_to_ehci_priv(hcd);
187	ehci = hcd_to_ehci(hcd);
188
189	priv->phy = devm_phy_get(&dev->dev, "usb");
190	if (IS_ERR(priv->phy)) {
191		err = PTR_ERR(priv->phy);
192		goto err_put_hcd;
193	}
194
195	for (clk = 0; clk < USB_MAX_CLKS; clk++) {
196		priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
197		if (IS_ERR(priv->clks[clk])) {
198			err = PTR_ERR(priv->clks[clk]);
199			if (err == -EPROBE_DEFER)
200				goto err_put_clks;
201			priv->clks[clk] = NULL;
202			break;
203		}
204	}
205
206	/* some SoCs don't have a dedicated 48Mhz clock, but those that
207	   do need the rate to be explicitly set */
208	priv->clk48 = devm_clk_get(&dev->dev, "clk48");
209	if (IS_ERR(priv->clk48)) {
210		dev_info(&dev->dev, "48MHz clk not found\n");
211		priv->clk48 = NULL;
212	}
213
214	priv->pwr = devm_reset_control_get_optional(&dev->dev, "power");
215	if (IS_ERR(priv->pwr)) {
216		err = PTR_ERR(priv->pwr);
217		if (err == -EPROBE_DEFER)
218			goto err_put_clks;
219		priv->pwr = NULL;
220	}
221
222	priv->rst = devm_reset_control_get_optional(&dev->dev, "softreset");
223	if (IS_ERR(priv->rst)) {
224		err = PTR_ERR(priv->rst);
225		if (err == -EPROBE_DEFER)
226			goto err_put_clks;
227		priv->rst = NULL;
228	}
229
230	if (pdata->power_on) {
231		err = pdata->power_on(dev);
232		if (err < 0)
233			goto err_put_clks;
234	}
235
236	hcd->rsrc_start = res_mem->start;
237	hcd->rsrc_len = resource_size(res_mem);
238
239	hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
240	if (IS_ERR(hcd->regs)) {
241		err = PTR_ERR(hcd->regs);
242		goto err_put_clks;
243	}
244
245	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
246	if (err)
247		goto err_put_clks;
248
249	device_wakeup_enable(hcd->self.controller);
250	platform_set_drvdata(dev, hcd);
251
252	return err;
253
254err_put_clks:
255	while (--clk >= 0)
256		clk_put(priv->clks[clk]);
257err_put_hcd:
258	if (pdata == &ehci_platform_defaults)
259		dev->dev.platform_data = NULL;
260
261	usb_put_hcd(hcd);
262
263	return err;
264}
265
266static int st_ehci_platform_remove(struct platform_device *dev)
267{
268	struct usb_hcd *hcd = platform_get_drvdata(dev);
269	struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
270	struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
271	int clk;
272
273	usb_remove_hcd(hcd);
274
275	if (pdata->power_off)
276		pdata->power_off(dev);
277
278	for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++)
279		clk_put(priv->clks[clk]);
280
281	usb_put_hcd(hcd);
282
283	if (pdata == &ehci_platform_defaults)
284		dev->dev.platform_data = NULL;
285
286	return 0;
287}
288
289#ifdef CONFIG_PM_SLEEP
290
291static int st_ehci_suspend(struct device *dev)
292{
293	struct usb_hcd *hcd = dev_get_drvdata(dev);
294	struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
295	struct platform_device *pdev =
296		container_of(dev, struct platform_device, dev);
297	bool do_wakeup = device_may_wakeup(dev);
298	int ret;
299
300	ret = ehci_suspend(hcd, do_wakeup);
301	if (ret)
302		return ret;
303
304	if (pdata->power_suspend)
305		pdata->power_suspend(pdev);
306
307	pinctrl_pm_select_sleep_state(dev);
308
309	return ret;
310}
311
312static int st_ehci_resume(struct device *dev)
313{
314	struct usb_hcd *hcd = dev_get_drvdata(dev);
315	struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
316	struct platform_device *pdev =
317		container_of(dev, struct platform_device, dev);
318	int err;
319
320	pinctrl_pm_select_default_state(dev);
321
322	if (pdata->power_on) {
323		err = pdata->power_on(pdev);
324		if (err < 0)
325			return err;
326	}
327
328	ehci_resume(hcd, false);
329	return 0;
330}
331
332static SIMPLE_DEV_PM_OPS(st_ehci_pm_ops, st_ehci_suspend, st_ehci_resume);
333
334#endif /* CONFIG_PM_SLEEP */
335
336static const struct of_device_id st_ehci_ids[] = {
337	{ .compatible = "st,st-ehci-300x", },
338	{ /* sentinel */ }
339};
340MODULE_DEVICE_TABLE(of, st_ehci_ids);
341
342static struct platform_driver ehci_platform_driver = {
343	.probe		= st_ehci_platform_probe,
344	.remove		= st_ehci_platform_remove,
345	.shutdown	= usb_hcd_platform_shutdown,
346	.driver		= {
347		.name	= "st-ehci",
348#ifdef CONFIG_PM_SLEEP
349		.pm	= &st_ehci_pm_ops,
350#endif
351		.of_match_table = st_ehci_ids,
352	}
353};
354
355static int __init ehci_platform_init(void)
356{
357	if (usb_disabled())
358		return -ENODEV;
359
360	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
361
362	ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides);
363	return platform_driver_register(&ehci_platform_driver);
364}
365module_init(ehci_platform_init);
366
367static void __exit ehci_platform_cleanup(void)
368{
369	platform_driver_unregister(&ehci_platform_driver);
370}
371module_exit(ehci_platform_cleanup);
372
373MODULE_DESCRIPTION(DRIVER_DESC);
374MODULE_AUTHOR("Peter Griffin <peter.griffin@linaro.org>");
375MODULE_LICENSE("GPL");
376