xref: /openbmc/linux/drivers/usb/host/ohci-st.c (revision a06c488d)
1 /*
2  * ST OHCI driver
3  *
4  * Copyright (C) 2014 STMicroelectronics – All Rights Reserved
5  *
6  * Author: Peter Griffin <peter.griffin@linaro.org>
7  *
8  * Derived from ohci-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/hrtimer.h>
18 #include <linux/io.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/err.h>
22 #include <linux/phy/phy.h>
23 #include <linux/platform_device.h>
24 #include <linux/reset.h>
25 #include <linux/usb/ohci_pdriver.h>
26 #include <linux/usb.h>
27 #include <linux/usb/hcd.h>
28 
29 #include "ohci.h"
30 
31 #define USB_MAX_CLKS 3
32 
33 struct st_ohci_platform_priv {
34 	struct clk *clks[USB_MAX_CLKS];
35 	struct clk *clk48;
36 	struct reset_control *rst;
37 	struct reset_control *pwr;
38 	struct phy *phy;
39 };
40 
41 #define DRIVER_DESC "OHCI STMicroelectronics driver"
42 
43 #define hcd_to_ohci_priv(h) \
44 	((struct st_ohci_platform_priv *)hcd_to_ohci(h)->priv)
45 
46 static const char hcd_name[] = "ohci-st";
47 
48 static int st_ohci_platform_power_on(struct platform_device *dev)
49 {
50 	struct usb_hcd *hcd = platform_get_drvdata(dev);
51 	struct st_ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
52 	int clk, ret;
53 
54 	ret = reset_control_deassert(priv->pwr);
55 	if (ret)
56 		return ret;
57 
58 	ret = reset_control_deassert(priv->rst);
59 	if (ret)
60 		goto err_assert_power;
61 
62 	/* some SoCs don't have a dedicated 48Mhz clock, but those that do
63 	   need the rate to be explicitly set */
64 	if (priv->clk48) {
65 		ret = clk_set_rate(priv->clk48, 48000000);
66 		if (ret)
67 			goto err_assert_reset;
68 	}
69 
70 	for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++) {
71 		ret = clk_prepare_enable(priv->clks[clk]);
72 		if (ret)
73 			goto err_disable_clks;
74 	}
75 
76 	ret = phy_init(priv->phy);
77 	if (ret)
78 		goto err_disable_clks;
79 
80 	ret = phy_power_on(priv->phy);
81 	if (ret)
82 		goto err_exit_phy;
83 
84 	return 0;
85 
86 err_exit_phy:
87 	phy_exit(priv->phy);
88 err_disable_clks:
89 	while (--clk >= 0)
90 		clk_disable_unprepare(priv->clks[clk]);
91 err_assert_reset:
92 	reset_control_assert(priv->rst);
93 err_assert_power:
94 	reset_control_assert(priv->pwr);
95 
96 	return ret;
97 }
98 
99 static void st_ohci_platform_power_off(struct platform_device *dev)
100 {
101 	struct usb_hcd *hcd = platform_get_drvdata(dev);
102 	struct st_ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
103 
104 	int clk;
105 
106 	reset_control_assert(priv->pwr);
107 
108 	reset_control_assert(priv->rst);
109 
110 	phy_power_off(priv->phy);
111 
112 	phy_exit(priv->phy);
113 
114 	for (clk = USB_MAX_CLKS - 1; clk >= 0; clk--)
115 		if (priv->clks[clk])
116 			clk_disable_unprepare(priv->clks[clk]);
117 }
118 
119 static struct hc_driver __read_mostly ohci_platform_hc_driver;
120 
121 static const struct ohci_driver_overrides platform_overrides __initconst = {
122 	.product_desc =		"ST OHCI controller",
123 	.extra_priv_size =	sizeof(struct st_ohci_platform_priv),
124 };
125 
126 static struct usb_ohci_pdata ohci_platform_defaults = {
127 	.power_on =		st_ohci_platform_power_on,
128 	.power_suspend =	st_ohci_platform_power_off,
129 	.power_off =		st_ohci_platform_power_off,
130 };
131 
132 static int st_ohci_platform_probe(struct platform_device *dev)
133 {
134 	struct usb_hcd *hcd;
135 	struct resource *res_mem;
136 	struct usb_ohci_pdata *pdata = &ohci_platform_defaults;
137 	struct st_ohci_platform_priv *priv;
138 	struct ohci_hcd *ohci;
139 	int err, irq, clk = 0;
140 
141 	if (usb_disabled())
142 		return -ENODEV;
143 
144 	irq = platform_get_irq(dev, 0);
145 	if (irq < 0) {
146 		dev_err(&dev->dev, "no irq provided");
147 		return irq;
148 	}
149 
150 	res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
151 	if (!res_mem) {
152 		dev_err(&dev->dev, "no memory resource provided");
153 		return -ENXIO;
154 	}
155 
156 	hcd = usb_create_hcd(&ohci_platform_hc_driver, &dev->dev,
157 			dev_name(&dev->dev));
158 	if (!hcd)
159 		return -ENOMEM;
160 
161 	platform_set_drvdata(dev, hcd);
162 	dev->dev.platform_data = pdata;
163 	priv = hcd_to_ohci_priv(hcd);
164 	ohci = hcd_to_ohci(hcd);
165 
166 	priv->phy = devm_phy_get(&dev->dev, "usb");
167 	if (IS_ERR(priv->phy)) {
168 		err = PTR_ERR(priv->phy);
169 		goto err_put_hcd;
170 	}
171 
172 	for (clk = 0; clk < USB_MAX_CLKS; clk++) {
173 		priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
174 		if (IS_ERR(priv->clks[clk])) {
175 			err = PTR_ERR(priv->clks[clk]);
176 			if (err == -EPROBE_DEFER)
177 				goto err_put_clks;
178 			priv->clks[clk] = NULL;
179 			break;
180 		}
181 	}
182 
183 	/* some SoCs don't have a dedicated 48Mhz clock, but those that
184 	   do need the rate to be explicitly set */
185 	priv->clk48 = devm_clk_get(&dev->dev, "clk48");
186 	if (IS_ERR(priv->clk48)) {
187 		dev_info(&dev->dev, "48MHz clk not found\n");
188 		priv->clk48 = NULL;
189 	}
190 
191 	priv->pwr = devm_reset_control_get_optional(&dev->dev, "power");
192 	if (IS_ERR(priv->pwr)) {
193 		err = PTR_ERR(priv->pwr);
194 		goto err_put_clks;
195 	}
196 
197 	priv->rst = devm_reset_control_get_optional(&dev->dev, "softreset");
198 	if (IS_ERR(priv->rst)) {
199 		err = PTR_ERR(priv->rst);
200 		goto err_put_clks;
201 	}
202 
203 	if (pdata->power_on) {
204 		err = pdata->power_on(dev);
205 		if (err < 0)
206 			goto err_power;
207 	}
208 
209 	hcd->rsrc_start = res_mem->start;
210 	hcd->rsrc_len = resource_size(res_mem);
211 
212 	hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
213 	if (IS_ERR(hcd->regs)) {
214 		err = PTR_ERR(hcd->regs);
215 		goto err_power;
216 	}
217 	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
218 	if (err)
219 		goto err_power;
220 
221 	device_wakeup_enable(hcd->self.controller);
222 
223 	platform_set_drvdata(dev, hcd);
224 
225 	return err;
226 
227 err_power:
228 	if (pdata->power_off)
229 		pdata->power_off(dev);
230 
231 err_put_clks:
232 	while (--clk >= 0)
233 		clk_put(priv->clks[clk]);
234 err_put_hcd:
235 	if (pdata == &ohci_platform_defaults)
236 		dev->dev.platform_data = NULL;
237 
238 	usb_put_hcd(hcd);
239 
240 	return err;
241 }
242 
243 static int st_ohci_platform_remove(struct platform_device *dev)
244 {
245 	struct usb_hcd *hcd = platform_get_drvdata(dev);
246 	struct usb_ohci_pdata *pdata = dev_get_platdata(&dev->dev);
247 	struct st_ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
248 	int clk;
249 
250 	usb_remove_hcd(hcd);
251 
252 	if (pdata->power_off)
253 		pdata->power_off(dev);
254 
255 
256 	for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++)
257 		clk_put(priv->clks[clk]);
258 
259 	usb_put_hcd(hcd);
260 
261 	if (pdata == &ohci_platform_defaults)
262 		dev->dev.platform_data = NULL;
263 
264 	return 0;
265 }
266 
267 #ifdef CONFIG_PM_SLEEP
268 
269 static int st_ohci_suspend(struct device *dev)
270 {
271 	struct usb_hcd *hcd = dev_get_drvdata(dev);
272 	struct usb_ohci_pdata *pdata = dev->platform_data;
273 	struct platform_device *pdev =
274 		container_of(dev, struct platform_device, dev);
275 	bool do_wakeup = device_may_wakeup(dev);
276 	int ret;
277 
278 	ret = ohci_suspend(hcd, do_wakeup);
279 	if (ret)
280 		return ret;
281 
282 	if (pdata->power_suspend)
283 		pdata->power_suspend(pdev);
284 
285 	return ret;
286 }
287 
288 static int st_ohci_resume(struct device *dev)
289 {
290 	struct usb_hcd *hcd = dev_get_drvdata(dev);
291 	struct usb_ohci_pdata *pdata = dev_get_platdata(dev);
292 	struct platform_device *pdev =
293 		container_of(dev, struct platform_device, dev);
294 	int err;
295 
296 	if (pdata->power_on) {
297 		err = pdata->power_on(pdev);
298 		if (err < 0)
299 			return err;
300 	}
301 
302 	ohci_resume(hcd, false);
303 	return 0;
304 }
305 
306 static SIMPLE_DEV_PM_OPS(st_ohci_pm_ops, st_ohci_suspend, st_ohci_resume);
307 
308 #endif /* CONFIG_PM_SLEEP */
309 
310 static const struct of_device_id st_ohci_platform_ids[] = {
311 	{ .compatible = "st,st-ohci-300x", },
312 	{ /* sentinel */ }
313 };
314 MODULE_DEVICE_TABLE(of, st_ohci_platform_ids);
315 
316 static struct platform_driver ohci_platform_driver = {
317 	.probe		= st_ohci_platform_probe,
318 	.remove		= st_ohci_platform_remove,
319 	.shutdown	= usb_hcd_platform_shutdown,
320 	.driver		= {
321 		.name	= "st-ohci",
322 #ifdef CONFIG_PM_SLEEP
323 		.pm	= &st_ohci_pm_ops,
324 #endif
325 		.of_match_table = st_ohci_platform_ids,
326 	}
327 };
328 
329 static int __init ohci_platform_init(void)
330 {
331 	if (usb_disabled())
332 		return -ENODEV;
333 
334 	pr_info("%s: " DRIVER_DESC "\n", hcd_name);
335 
336 	ohci_init_driver(&ohci_platform_hc_driver, &platform_overrides);
337 	return platform_driver_register(&ohci_platform_driver);
338 }
339 module_init(ohci_platform_init);
340 
341 static void __exit ohci_platform_cleanup(void)
342 {
343 	platform_driver_unregister(&ohci_platform_driver);
344 }
345 module_exit(ohci_platform_cleanup);
346 
347 MODULE_DESCRIPTION(DRIVER_DESC);
348 MODULE_AUTHOR("Peter Griffin <peter.griffin@linaro.org>");
349 MODULE_LICENSE("GPL");
350