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 struct ehci_hcd *ehci;
156 int err, irq, clk = 0;
157
158 if (usb_disabled())
159 return -ENODEV;
160
161 irq = platform_get_irq(dev, 0);
162 if (irq < 0) {
163 dev_err(&dev->dev, "no irq provided");
164 return irq;
165 }
166 res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
167 if (!res_mem) {
168 dev_err(&dev->dev, "no memory resource provided");
169 return -ENXIO;
170 }
171
172 hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev,
173 dev_name(&dev->dev));
174 if (!hcd)
175 return -ENOMEM;
176
177 platform_set_drvdata(dev, hcd);
178 dev->dev.platform_data = pdata;
179 priv = hcd_to_ehci_priv(hcd);
180 ehci = hcd_to_ehci(hcd);
181
182 priv->phy = devm_phy_get(&dev->dev, "usb");
183 if (IS_ERR(priv->phy)) {
184 err = PTR_ERR(priv->phy);
185 goto err_put_hcd;
186 }
187
188 for (clk = 0; clk < USB_MAX_CLKS; clk++) {
189 priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
190 if (IS_ERR(priv->clks[clk])) {
191 err = PTR_ERR(priv->clks[clk]);
192 if (err == -EPROBE_DEFER)
193 goto err_put_clks;
194 priv->clks[clk] = NULL;
195 break;
196 }
197 }
198
199 /* some SoCs don't have a dedicated 48Mhz clock, but those that
200 do need the rate to be explicitly set */
201 priv->clk48 = devm_clk_get(&dev->dev, "clk48");
202 if (IS_ERR(priv->clk48)) {
203 dev_info(&dev->dev, "48MHz clk not found\n");
204 priv->clk48 = NULL;
205 }
206
207 priv->pwr =
208 devm_reset_control_get_optional_shared(&dev->dev, "power");
209 if (IS_ERR(priv->pwr)) {
210 err = PTR_ERR(priv->pwr);
211 if (err == -EPROBE_DEFER)
212 goto err_put_clks;
213 priv->pwr = NULL;
214 }
215
216 priv->rst =
217 devm_reset_control_get_optional_shared(&dev->dev, "softreset");
218 if (IS_ERR(priv->rst)) {
219 err = PTR_ERR(priv->rst);
220 if (err == -EPROBE_DEFER)
221 goto err_put_clks;
222 priv->rst = NULL;
223 }
224
225 if (pdata->power_on) {
226 err = pdata->power_on(dev);
227 if (err < 0)
228 goto err_put_clks;
229 }
230
231 hcd->rsrc_start = res_mem->start;
232 hcd->rsrc_len = resource_size(res_mem);
233
234 hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
235 if (IS_ERR(hcd->regs)) {
236 err = PTR_ERR(hcd->regs);
237 goto err_put_clks;
238 }
239
240 err = usb_add_hcd(hcd, irq, IRQF_SHARED);
241 if (err)
242 goto err_put_clks;
243
244 device_wakeup_enable(hcd->self.controller);
245 platform_set_drvdata(dev, hcd);
246
247 return err;
248
249 err_put_clks:
250 while (--clk >= 0)
251 clk_put(priv->clks[clk]);
252 err_put_hcd:
253 if (pdata == &ehci_platform_defaults)
254 dev->dev.platform_data = NULL;
255
256 usb_put_hcd(hcd);
257
258 return err;
259 }
260
st_ehci_platform_remove(struct platform_device * dev)261 static int st_ehci_platform_remove(struct platform_device *dev)
262 {
263 struct usb_hcd *hcd = platform_get_drvdata(dev);
264 struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
265 struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
266 int clk;
267
268 usb_remove_hcd(hcd);
269
270 if (pdata->power_off)
271 pdata->power_off(dev);
272
273 for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++)
274 clk_put(priv->clks[clk]);
275
276 usb_put_hcd(hcd);
277
278 if (pdata == &ehci_platform_defaults)
279 dev->dev.platform_data = NULL;
280
281 return 0;
282 }
283
284 #ifdef CONFIG_PM_SLEEP
285
st_ehci_suspend(struct device * dev)286 static int st_ehci_suspend(struct device *dev)
287 {
288 struct usb_hcd *hcd = dev_get_drvdata(dev);
289 struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
290 struct platform_device *pdev = to_platform_device(dev);
291 bool do_wakeup = device_may_wakeup(dev);
292 int ret;
293
294 ret = ehci_suspend(hcd, do_wakeup);
295 if (ret)
296 return ret;
297
298 if (pdata->power_suspend)
299 pdata->power_suspend(pdev);
300
301 pinctrl_pm_select_sleep_state(dev);
302
303 return ret;
304 }
305
st_ehci_resume(struct device * dev)306 static int st_ehci_resume(struct device *dev)
307 {
308 struct usb_hcd *hcd = dev_get_drvdata(dev);
309 struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
310 struct platform_device *pdev = to_platform_device(dev);
311 int err;
312
313 pinctrl_pm_select_default_state(dev);
314
315 if (pdata->power_on) {
316 err = pdata->power_on(pdev);
317 if (err < 0)
318 return err;
319 }
320
321 ehci_resume(hcd, false);
322 return 0;
323 }
324
325 static SIMPLE_DEV_PM_OPS(st_ehci_pm_ops, st_ehci_suspend, st_ehci_resume);
326
327 #endif /* CONFIG_PM_SLEEP */
328
329 static const struct of_device_id st_ehci_ids[] = {
330 { .compatible = "st,st-ehci-300x", },
331 { /* sentinel */ }
332 };
333 MODULE_DEVICE_TABLE(of, st_ehci_ids);
334
335 static struct platform_driver ehci_platform_driver = {
336 .probe = st_ehci_platform_probe,
337 .remove = st_ehci_platform_remove,
338 .shutdown = usb_hcd_platform_shutdown,
339 .driver = {
340 .name = "st-ehci",
341 #ifdef CONFIG_PM_SLEEP
342 .pm = &st_ehci_pm_ops,
343 #endif
344 .of_match_table = st_ehci_ids,
345 }
346 };
347
ehci_platform_init(void)348 static int __init ehci_platform_init(void)
349 {
350 if (usb_disabled())
351 return -ENODEV;
352
353 pr_info("%s: " DRIVER_DESC "\n", hcd_name);
354
355 ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides);
356 return platform_driver_register(&ehci_platform_driver);
357 }
358 module_init(ehci_platform_init);
359
ehci_platform_cleanup(void)360 static void __exit ehci_platform_cleanup(void)
361 {
362 platform_driver_unregister(&ehci_platform_driver);
363 }
364 module_exit(ehci_platform_cleanup);
365
366 MODULE_DESCRIPTION(DRIVER_DESC);
367 MODULE_AUTHOR("Peter Griffin <peter.griffin@linaro.org>");
368 MODULE_LICENSE("GPL");
369
