1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * ST EHCI driver
4 *
5 * Copyright (C) 2014 STMicroelectronics – All Rights Reserved
6 *
7 * Author: Peter Griffin <peter.griffin@linaro.org>
8 *
9 * Derived from ehci-platform.c
10 */
11
12 #include <linux/clk.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/err.h>
15 #include <linux/kernel.h>
16 #include <linux/hrtimer.h>
17 #include <linux/io.h>
18 #include <linux/module.h>
19 #include <linux/of.h>
20 #include <linux/phy/phy.h>
21 #include <linux/platform_device.h>
22 #include <linux/reset.h>
23 #include <linux/usb.h>
24 #include <linux/usb/hcd.h>
25 #include <linux/usb/ehci_pdriver.h>
26 #include <linux/pinctrl/consumer.h>
27
28 #include "ehci.h"
29
30 #define USB_MAX_CLKS 3
31
32 struct st_ehci_platform_priv {
33 struct clk *clks[USB_MAX_CLKS];
34 struct clk *clk48;
35 struct reset_control *rst;
36 struct reset_control *pwr;
37 struct phy *phy;
38 };
39
40 #define DRIVER_DESC "EHCI STMicroelectronics driver"
41
42 #define hcd_to_ehci_priv(h) \
43 ((struct st_ehci_platform_priv *)hcd_to_ehci(h)->priv)
44
45 static const char hcd_name[] = "ehci-st";
46
47 #define EHCI_CAPS_SIZE 0x10
48 #define AHB2STBUS_INSREG01 (EHCI_CAPS_SIZE + 0x84)
49
st_ehci_platform_reset(struct usb_hcd * hcd)50 static int st_ehci_platform_reset(struct usb_hcd *hcd)
51 {
52 struct platform_device *pdev = to_platform_device(hcd->self.controller);
53 struct usb_ehci_pdata *pdata = dev_get_platdata(&pdev->dev);
54 struct ehci_hcd *ehci = hcd_to_ehci(hcd);
55 u32 threshold;
56
57 /* Set EHCI packet buffer IN/OUT threshold to 128 bytes */
58 threshold = 128 | (128 << 16);
59 writel(threshold, hcd->regs + AHB2STBUS_INSREG01);
60
61 ehci->caps = hcd->regs + pdata->caps_offset;
62 return ehci_setup(hcd);
63 }
64
st_ehci_platform_power_on(struct platform_device * dev)65 static int st_ehci_platform_power_on(struct platform_device *dev)
66 {
67 struct usb_hcd *hcd = platform_get_drvdata(dev);
68 struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
69 int clk, ret;
70
71 ret = reset_control_deassert(priv->pwr);
72 if (ret)
73 return ret;
74
75 ret = reset_control_deassert(priv->rst);
76 if (ret)
77 goto err_assert_power;
78
79 /* some SoCs don't have a dedicated 48Mhz clock, but those that do
80 need the rate to be explicitly set */
81 if (priv->clk48) {
82 ret = clk_set_rate(priv->clk48, 48000000);
83 if (ret)
84 goto err_assert_reset;
85 }
86
87 for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++) {
88 ret = clk_prepare_enable(priv->clks[clk]);
89 if (ret)
90 goto err_disable_clks;
91 }
92
93 ret = phy_init(priv->phy);
94 if (ret)
95 goto err_disable_clks;
96
97 ret = phy_power_on(priv->phy);
98 if (ret)
99 goto err_exit_phy;
100
101 return 0;
102
103 err_exit_phy:
104 phy_exit(priv->phy);
105 err_disable_clks:
106 while (--clk >= 0)
107 clk_disable_unprepare(priv->clks[clk]);
108 err_assert_reset:
109 reset_control_assert(priv->rst);
110 err_assert_power:
111 reset_control_assert(priv->pwr);
112
113 return ret;
114 }
115
st_ehci_platform_power_off(struct platform_device * dev)116 static void st_ehci_platform_power_off(struct platform_device *dev)
117 {
118 struct usb_hcd *hcd = platform_get_drvdata(dev);
119 struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
120 int clk;
121
122 reset_control_assert(priv->pwr);
123
124 reset_control_assert(priv->rst);
125
126 phy_power_off(priv->phy);
127
128 phy_exit(priv->phy);
129
130 for (clk = USB_MAX_CLKS - 1; clk >= 0; clk--)
131 if (priv->clks[clk])
132 clk_disable_unprepare(priv->clks[clk]);
133
134 }
135
136 static struct hc_driver __read_mostly ehci_platform_hc_driver;
137
138 static const struct ehci_driver_overrides platform_overrides __initconst = {
139 .reset = st_ehci_platform_reset,
140 .extra_priv_size = sizeof(struct st_ehci_platform_priv),
141 };
142
143 static struct usb_ehci_pdata ehci_platform_defaults = {
144 .power_on = st_ehci_platform_power_on,
145 .power_suspend = st_ehci_platform_power_off,
146 .power_off = st_ehci_platform_power_off,
147 };
148
st_ehci_platform_probe(struct platform_device * dev)149 static int st_ehci_platform_probe(struct platform_device *dev)
150 {
151 struct usb_hcd *hcd;
152 struct resource *res_mem;
153 struct usb_ehci_pdata *pdata = &ehci_platform_defaults;
154 struct st_ehci_platform_priv *priv;
155 int err, irq, clk = 0;
156
157 if (usb_disabled())
158 return -ENODEV;
159
160 irq = platform_get_irq(dev, 0);
161 if (irq < 0)
162 return irq;
163 res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
164 if (!res_mem) {
165 dev_err(&dev->dev, "no memory resource provided");
166 return -ENXIO;
167 }
168
169 hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev,
170 dev_name(&dev->dev));
171 if (!hcd)
172 return -ENOMEM;
173
174 platform_set_drvdata(dev, hcd);
175 dev->dev.platform_data = pdata;
176 priv = hcd_to_ehci_priv(hcd);
177
178 priv->phy = devm_phy_get(&dev->dev, "usb");
179 if (IS_ERR(priv->phy)) {
180 err = PTR_ERR(priv->phy);
181 goto err_put_hcd;
182 }
183
184 for (clk = 0; clk < USB_MAX_CLKS; clk++) {
185 priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
186 if (IS_ERR(priv->clks[clk])) {
187 err = PTR_ERR(priv->clks[clk]);
188 if (err == -EPROBE_DEFER)
189 goto err_put_clks;
190 priv->clks[clk] = NULL;
191 break;
192 }
193 }
194
195 /* some SoCs don't have a dedicated 48Mhz clock, but those that
196 do need the rate to be explicitly set */
197 priv->clk48 = devm_clk_get(&dev->dev, "clk48");
198 if (IS_ERR(priv->clk48)) {
199 dev_info(&dev->dev, "48MHz clk not found\n");
200 priv->clk48 = NULL;
201 }
202
203 priv->pwr =
204 devm_reset_control_get_optional_shared(&dev->dev, "power");
205 if (IS_ERR(priv->pwr)) {
206 err = PTR_ERR(priv->pwr);
207 if (err == -EPROBE_DEFER)
208 goto err_put_clks;
209 priv->pwr = NULL;
210 }
211
212 priv->rst =
213 devm_reset_control_get_optional_shared(&dev->dev, "softreset");
214 if (IS_ERR(priv->rst)) {
215 err = PTR_ERR(priv->rst);
216 if (err == -EPROBE_DEFER)
217 goto err_put_clks;
218 priv->rst = NULL;
219 }
220
221 if (pdata->power_on) {
222 err = pdata->power_on(dev);
223 if (err < 0)
224 goto err_put_clks;
225 }
226
227 hcd->rsrc_start = res_mem->start;
228 hcd->rsrc_len = resource_size(res_mem);
229
230 hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
231 if (IS_ERR(hcd->regs)) {
232 err = PTR_ERR(hcd->regs);
233 goto err_put_clks;
234 }
235
236 err = usb_add_hcd(hcd, irq, IRQF_SHARED);
237 if (err)
238 goto err_put_clks;
239
240 device_wakeup_enable(hcd->self.controller);
241 platform_set_drvdata(dev, hcd);
242
243 return err;
244
245 err_put_clks:
246 while (--clk >= 0)
247 clk_put(priv->clks[clk]);
248 err_put_hcd:
249 if (pdata == &ehci_platform_defaults)
250 dev->dev.platform_data = NULL;
251
252 usb_put_hcd(hcd);
253
254 return err;
255 }
256
st_ehci_platform_remove(struct platform_device * dev)257 static int st_ehci_platform_remove(struct platform_device *dev)
258 {
259 struct usb_hcd *hcd = platform_get_drvdata(dev);
260 struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
261 struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
262 int clk;
263
264 usb_remove_hcd(hcd);
265
266 if (pdata->power_off)
267 pdata->power_off(dev);
268
269 for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++)
270 clk_put(priv->clks[clk]);
271
272 usb_put_hcd(hcd);
273
274 if (pdata == &ehci_platform_defaults)
275 dev->dev.platform_data = NULL;
276
277 return 0;
278 }
279
280 #ifdef CONFIG_PM_SLEEP
281
st_ehci_suspend(struct device * dev)282 static int st_ehci_suspend(struct device *dev)
283 {
284 struct usb_hcd *hcd = dev_get_drvdata(dev);
285 struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
286 struct platform_device *pdev = to_platform_device(dev);
287 bool do_wakeup = device_may_wakeup(dev);
288 int ret;
289
290 ret = ehci_suspend(hcd, do_wakeup);
291 if (ret)
292 return ret;
293
294 if (pdata->power_suspend)
295 pdata->power_suspend(pdev);
296
297 pinctrl_pm_select_sleep_state(dev);
298
299 return ret;
300 }
301
st_ehci_resume(struct device * dev)302 static int st_ehci_resume(struct device *dev)
303 {
304 struct usb_hcd *hcd = dev_get_drvdata(dev);
305 struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
306 struct platform_device *pdev = to_platform_device(dev);
307 int err;
308
309 pinctrl_pm_select_default_state(dev);
310
311 if (pdata->power_on) {
312 err = pdata->power_on(pdev);
313 if (err < 0)
314 return err;
315 }
316
317 ehci_resume(hcd, false);
318 return 0;
319 }
320
321 static SIMPLE_DEV_PM_OPS(st_ehci_pm_ops, st_ehci_suspend, st_ehci_resume);
322
323 #endif /* CONFIG_PM_SLEEP */
324
325 static const struct of_device_id st_ehci_ids[] = {
326 { .compatible = "st,st-ehci-300x", },
327 { /* sentinel */ }
328 };
329 MODULE_DEVICE_TABLE(of, st_ehci_ids);
330
331 static struct platform_driver ehci_platform_driver = {
332 .probe = st_ehci_platform_probe,
333 .remove = st_ehci_platform_remove,
334 .shutdown = usb_hcd_platform_shutdown,
335 .driver = {
336 .name = "st-ehci",
337 #ifdef CONFIG_PM_SLEEP
338 .pm = &st_ehci_pm_ops,
339 #endif
340 .of_match_table = st_ehci_ids,
341 }
342 };
343
ehci_platform_init(void)344 static int __init ehci_platform_init(void)
345 {
346 if (usb_disabled())
347 return -ENODEV;
348
349 pr_info("%s: " DRIVER_DESC "\n", hcd_name);
350
351 ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides);
352 return platform_driver_register(&ehci_platform_driver);
353 }
354 module_init(ehci_platform_init);
355
ehci_platform_cleanup(void)356 static void __exit ehci_platform_cleanup(void)
357 {
358 platform_driver_unregister(&ehci_platform_driver);
359 }
360 module_exit(ehci_platform_cleanup);
361
362 MODULE_DESCRIPTION(DRIVER_DESC);
363 MODULE_AUTHOR("Peter Griffin <peter.griffin@linaro.org>");
364 MODULE_LICENSE("GPL");
365
