xref: /openbmc/linux/drivers/usb/host/ohci-st.c (revision ba0b3af7)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ST OHCI driver
4  *
5  * Copyright (C) 2014 STMicroelectronics – All Rights Reserved
6  *
7  * Author: Peter Griffin <peter.griffin@linaro.org>
8  *
9  * Derived from ohci-platform.c
10  */
11 
12 #include <linux/clk.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/hrtimer.h>
15 #include <linux/io.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/err.h>
19 #include <linux/phy/phy.h>
20 #include <linux/platform_device.h>
21 #include <linux/reset.h>
22 #include <linux/usb/ohci_pdriver.h>
23 #include <linux/usb.h>
24 #include <linux/usb/hcd.h>
25 
26 #include "ohci.h"
27 
28 #define USB_MAX_CLKS 3
29 
30 struct st_ohci_platform_priv {
31 	struct clk *clks[USB_MAX_CLKS];
32 	struct clk *clk48;
33 	struct reset_control *rst;
34 	struct reset_control *pwr;
35 	struct phy *phy;
36 };
37 
38 #define DRIVER_DESC "OHCI STMicroelectronics driver"
39 
40 #define hcd_to_ohci_priv(h) \
41 	((struct st_ohci_platform_priv *)hcd_to_ohci(h)->priv)
42 
st_ohci_platform_power_on(struct platform_device * dev)43 static int st_ohci_platform_power_on(struct platform_device *dev)
44 {
45 	struct usb_hcd *hcd = platform_get_drvdata(dev);
46 	struct st_ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
47 	int clk, ret;
48 
49 	ret = reset_control_deassert(priv->pwr);
50 	if (ret)
51 		return ret;
52 
53 	ret = reset_control_deassert(priv->rst);
54 	if (ret)
55 		goto err_assert_power;
56 
57 	/* some SoCs don't have a dedicated 48Mhz clock, but those that do
58 	   need the rate to be explicitly set */
59 	if (priv->clk48) {
60 		ret = clk_set_rate(priv->clk48, 48000000);
61 		if (ret)
62 			goto err_assert_reset;
63 	}
64 
65 	for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++) {
66 		ret = clk_prepare_enable(priv->clks[clk]);
67 		if (ret)
68 			goto err_disable_clks;
69 	}
70 
71 	ret = phy_init(priv->phy);
72 	if (ret)
73 		goto err_disable_clks;
74 
75 	ret = phy_power_on(priv->phy);
76 	if (ret)
77 		goto err_exit_phy;
78 
79 	return 0;
80 
81 err_exit_phy:
82 	phy_exit(priv->phy);
83 err_disable_clks:
84 	while (--clk >= 0)
85 		clk_disable_unprepare(priv->clks[clk]);
86 err_assert_reset:
87 	reset_control_assert(priv->rst);
88 err_assert_power:
89 	reset_control_assert(priv->pwr);
90 
91 	return ret;
92 }
93 
st_ohci_platform_power_off(struct platform_device * dev)94 static void st_ohci_platform_power_off(struct platform_device *dev)
95 {
96 	struct usb_hcd *hcd = platform_get_drvdata(dev);
97 	struct st_ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
98 
99 	int clk;
100 
101 	reset_control_assert(priv->pwr);
102 
103 	reset_control_assert(priv->rst);
104 
105 	phy_power_off(priv->phy);
106 
107 	phy_exit(priv->phy);
108 
109 	for (clk = USB_MAX_CLKS - 1; clk >= 0; clk--)
110 		if (priv->clks[clk])
111 			clk_disable_unprepare(priv->clks[clk]);
112 }
113 
114 static struct hc_driver __read_mostly ohci_platform_hc_driver;
115 
116 static const struct ohci_driver_overrides platform_overrides __initconst = {
117 	.product_desc =		"ST OHCI controller",
118 	.extra_priv_size =	sizeof(struct st_ohci_platform_priv),
119 };
120 
121 static struct usb_ohci_pdata ohci_platform_defaults = {
122 	.power_on =		st_ohci_platform_power_on,
123 	.power_suspend =	st_ohci_platform_power_off,
124 	.power_off =		st_ohci_platform_power_off,
125 };
126 
st_ohci_platform_probe(struct platform_device * dev)127 static int st_ohci_platform_probe(struct platform_device *dev)
128 {
129 	struct usb_hcd *hcd;
130 	struct resource *res_mem;
131 	struct usb_ohci_pdata *pdata = &ohci_platform_defaults;
132 	struct st_ohci_platform_priv *priv;
133 	int err, irq, clk = 0;
134 
135 	if (usb_disabled())
136 		return -ENODEV;
137 
138 	irq = platform_get_irq(dev, 0);
139 	if (irq < 0)
140 		return irq;
141 
142 	hcd = usb_create_hcd(&ohci_platform_hc_driver, &dev->dev,
143 			dev_name(&dev->dev));
144 	if (!hcd)
145 		return -ENOMEM;
146 
147 	platform_set_drvdata(dev, hcd);
148 	dev->dev.platform_data = pdata;
149 	priv = hcd_to_ohci_priv(hcd);
150 
151 	priv->phy = devm_phy_get(&dev->dev, "usb");
152 	if (IS_ERR(priv->phy)) {
153 		err = PTR_ERR(priv->phy);
154 		goto err_put_hcd;
155 	}
156 
157 	for (clk = 0; clk < USB_MAX_CLKS; clk++) {
158 		priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
159 		if (IS_ERR(priv->clks[clk])) {
160 			err = PTR_ERR(priv->clks[clk]);
161 			if (err == -EPROBE_DEFER)
162 				goto err_put_clks;
163 			priv->clks[clk] = NULL;
164 			break;
165 		}
166 	}
167 
168 	/* some SoCs don't have a dedicated 48Mhz clock, but those that
169 	   do need the rate to be explicitly set */
170 	priv->clk48 = devm_clk_get(&dev->dev, "clk48");
171 	if (IS_ERR(priv->clk48)) {
172 		dev_info(&dev->dev, "48MHz clk not found\n");
173 		priv->clk48 = NULL;
174 	}
175 
176 	priv->pwr =
177 		devm_reset_control_get_optional_shared(&dev->dev, "power");
178 	if (IS_ERR(priv->pwr)) {
179 		err = PTR_ERR(priv->pwr);
180 		goto err_put_clks;
181 	}
182 
183 	priv->rst =
184 		devm_reset_control_get_optional_shared(&dev->dev, "softreset");
185 	if (IS_ERR(priv->rst)) {
186 		err = PTR_ERR(priv->rst);
187 		goto err_put_clks;
188 	}
189 
190 	if (pdata->power_on) {
191 		err = pdata->power_on(dev);
192 		if (err < 0)
193 			goto err_power;
194 	}
195 
196 	hcd->regs = devm_platform_get_and_ioremap_resource(dev, 0, &res_mem);
197 	if (IS_ERR(hcd->regs)) {
198 		err = PTR_ERR(hcd->regs);
199 		goto err_power;
200 	}
201 	hcd->rsrc_start = res_mem->start;
202 	hcd->rsrc_len = resource_size(res_mem);
203 
204 	err = usb_add_hcd(hcd, irq, IRQF_SHARED);
205 	if (err)
206 		goto err_power;
207 
208 	device_wakeup_enable(hcd->self.controller);
209 
210 	platform_set_drvdata(dev, hcd);
211 
212 	return err;
213 
214 err_power:
215 	if (pdata->power_off)
216 		pdata->power_off(dev);
217 
218 err_put_clks:
219 	while (--clk >= 0)
220 		clk_put(priv->clks[clk]);
221 err_put_hcd:
222 	if (pdata == &ohci_platform_defaults)
223 		dev->dev.platform_data = NULL;
224 
225 	usb_put_hcd(hcd);
226 
227 	return err;
228 }
229 
st_ohci_platform_remove(struct platform_device * dev)230 static void st_ohci_platform_remove(struct platform_device *dev)
231 {
232 	struct usb_hcd *hcd = platform_get_drvdata(dev);
233 	struct usb_ohci_pdata *pdata = dev_get_platdata(&dev->dev);
234 	struct st_ohci_platform_priv *priv = hcd_to_ohci_priv(hcd);
235 	int clk;
236 
237 	usb_remove_hcd(hcd);
238 
239 	if (pdata->power_off)
240 		pdata->power_off(dev);
241 
242 
243 	for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++)
244 		clk_put(priv->clks[clk]);
245 
246 	usb_put_hcd(hcd);
247 
248 	if (pdata == &ohci_platform_defaults)
249 		dev->dev.platform_data = NULL;
250 }
251 
252 #ifdef CONFIG_PM_SLEEP
253 
st_ohci_suspend(struct device * dev)254 static int st_ohci_suspend(struct device *dev)
255 {
256 	struct usb_hcd *hcd = dev_get_drvdata(dev);
257 	struct usb_ohci_pdata *pdata = dev->platform_data;
258 	struct platform_device *pdev = to_platform_device(dev);
259 	bool do_wakeup = device_may_wakeup(dev);
260 	int ret;
261 
262 	ret = ohci_suspend(hcd, do_wakeup);
263 	if (ret)
264 		return ret;
265 
266 	if (pdata->power_suspend)
267 		pdata->power_suspend(pdev);
268 
269 	return ret;
270 }
271 
st_ohci_resume(struct device * dev)272 static int st_ohci_resume(struct device *dev)
273 {
274 	struct usb_hcd *hcd = dev_get_drvdata(dev);
275 	struct usb_ohci_pdata *pdata = dev_get_platdata(dev);
276 	struct platform_device *pdev = to_platform_device(dev);
277 	int err;
278 
279 	if (pdata->power_on) {
280 		err = pdata->power_on(pdev);
281 		if (err < 0)
282 			return err;
283 	}
284 
285 	ohci_resume(hcd, false);
286 	return 0;
287 }
288 
289 static SIMPLE_DEV_PM_OPS(st_ohci_pm_ops, st_ohci_suspend, st_ohci_resume);
290 
291 #endif /* CONFIG_PM_SLEEP */
292 
293 static const struct of_device_id st_ohci_platform_ids[] = {
294 	{ .compatible = "st,st-ohci-300x", },
295 	{ /* sentinel */ }
296 };
297 MODULE_DEVICE_TABLE(of, st_ohci_platform_ids);
298 
299 static struct platform_driver ohci_platform_driver = {
300 	.probe		= st_ohci_platform_probe,
301 	.remove_new	= st_ohci_platform_remove,
302 	.shutdown	= usb_hcd_platform_shutdown,
303 	.driver		= {
304 		.name	= "st-ohci",
305 #ifdef CONFIG_PM_SLEEP
306 		.pm	= &st_ohci_pm_ops,
307 #endif
308 		.of_match_table = st_ohci_platform_ids,
309 	}
310 };
311 
ohci_platform_init(void)312 static int __init ohci_platform_init(void)
313 {
314 	if (usb_disabled())
315 		return -ENODEV;
316 
317 	ohci_init_driver(&ohci_platform_hc_driver, &platform_overrides);
318 	return platform_driver_register(&ohci_platform_driver);
319 }
320 module_init(ohci_platform_init);
321 
ohci_platform_cleanup(void)322 static void __exit ohci_platform_cleanup(void)
323 {
324 	platform_driver_unregister(&ohci_platform_driver);
325 }
326 module_exit(ohci_platform_cleanup);
327 
328 MODULE_DESCRIPTION(DRIVER_DESC);
329 MODULE_AUTHOR("Peter Griffin <peter.griffin@linaro.org>");
330 MODULE_LICENSE("GPL");
331