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