1 /*
2 * ST EHCI driver
3 *
4 * Copyright (C) 2014 STMicroelectronics – All Rights Reserved
5 *
6 * Author: Peter Griffin <peter.griffin@linaro.org>
7 *
8 * Derived from ehci-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/err.h>
18 #include <linux/kernel.h>
19 #include <linux/hrtimer.h>
20 #include <linux/io.h>
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/phy/phy.h>
24 #include <linux/platform_device.h>
25 #include <linux/reset.h>
26 #include <linux/usb.h>
27 #include <linux/usb/hcd.h>
28 #include <linux/usb/ehci_pdriver.h>
29
30 #include "ehci.h"
31
32 #define USB_MAX_CLKS 3
33
34 struct st_ehci_platform_priv {
35 struct clk *clks[USB_MAX_CLKS];
36 struct clk *clk48;
37 struct reset_control *rst;
38 struct reset_control *pwr;
39 struct phy *phy;
40 };
41
42 #define DRIVER_DESC "EHCI STMicroelectronics driver"
43
44 #define hcd_to_ehci_priv(h) \
45 ((struct st_ehci_platform_priv *)hcd_to_ehci(h)->priv)
46
47 static const char hcd_name[] = "ehci-st";
48
49 #define EHCI_CAPS_SIZE 0x10
50 #define AHB2STBUS_INSREG01 (EHCI_CAPS_SIZE + 0x84)
51
st_ehci_platform_reset(struct usb_hcd * hcd)52 static int st_ehci_platform_reset(struct usb_hcd *hcd)
53 {
54 struct platform_device *pdev = to_platform_device(hcd->self.controller);
55 struct usb_ehci_pdata *pdata = dev_get_platdata(&pdev->dev);
56 struct ehci_hcd *ehci = hcd_to_ehci(hcd);
57 int retval;
58 u32 threshold;
59
60 /* Set EHCI packet buffer IN/OUT threshold to 128 bytes */
61 threshold = 128 | (128 << 16);
62 writel(threshold, hcd->regs + AHB2STBUS_INSREG01);
63
64 ehci->caps = hcd->regs + pdata->caps_offset;
65 retval = ehci_setup(hcd);
66 if (retval)
67 return retval;
68
69 return 0;
70 }
71
st_ehci_platform_power_on(struct platform_device * dev)72 static int st_ehci_platform_power_on(struct platform_device *dev)
73 {
74 struct usb_hcd *hcd = platform_get_drvdata(dev);
75 struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
76 int clk, ret;
77
78 ret = reset_control_deassert(priv->pwr);
79 if (ret)
80 return ret;
81
82 ret = reset_control_deassert(priv->rst);
83 if (ret)
84 goto err_assert_power;
85
86 /* some SoCs don't have a dedicated 48Mhz clock, but those that do
87 need the rate to be explicitly set */
88 if (priv->clk48) {
89 ret = clk_set_rate(priv->clk48, 48000000);
90 if (ret)
91 goto err_assert_reset;
92 }
93
94 for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++) {
95 ret = clk_prepare_enable(priv->clks[clk]);
96 if (ret)
97 goto err_disable_clks;
98 }
99
100 ret = phy_init(priv->phy);
101 if (ret)
102 goto err_disable_clks;
103
104 ret = phy_power_on(priv->phy);
105 if (ret)
106 goto err_exit_phy;
107
108 return 0;
109
110 err_exit_phy:
111 phy_exit(priv->phy);
112 err_disable_clks:
113 while (--clk >= 0)
114 clk_disable_unprepare(priv->clks[clk]);
115 err_assert_reset:
116 reset_control_assert(priv->rst);
117 err_assert_power:
118 reset_control_assert(priv->pwr);
119
120 return ret;
121 }
122
st_ehci_platform_power_off(struct platform_device * dev)123 static void st_ehci_platform_power_off(struct platform_device *dev)
124 {
125 struct usb_hcd *hcd = platform_get_drvdata(dev);
126 struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
127 int clk;
128
129 reset_control_assert(priv->pwr);
130
131 reset_control_assert(priv->rst);
132
133 phy_power_off(priv->phy);
134
135 phy_exit(priv->phy);
136
137 for (clk = USB_MAX_CLKS - 1; clk >= 0; clk--)
138 if (priv->clks[clk])
139 clk_disable_unprepare(priv->clks[clk]);
140
141 }
142
143 static struct hc_driver __read_mostly ehci_platform_hc_driver;
144
145 static const struct ehci_driver_overrides platform_overrides __initconst = {
146 .reset = st_ehci_platform_reset,
147 .extra_priv_size = sizeof(struct st_ehci_platform_priv),
148 };
149
150 static struct usb_ehci_pdata ehci_platform_defaults = {
151 .power_on = st_ehci_platform_power_on,
152 .power_suspend = st_ehci_platform_power_off,
153 .power_off = st_ehci_platform_power_off,
154 };
155
st_ehci_platform_probe(struct platform_device * dev)156 static int st_ehci_platform_probe(struct platform_device *dev)
157 {
158 struct usb_hcd *hcd;
159 struct resource *res_mem;
160 struct usb_ehci_pdata *pdata = &ehci_platform_defaults;
161 struct st_ehci_platform_priv *priv;
162 struct ehci_hcd *ehci;
163 int err, irq, clk = 0;
164
165 if (usb_disabled())
166 return -ENODEV;
167
168 irq = platform_get_irq(dev, 0);
169 if (irq < 0) {
170 dev_err(&dev->dev, "no irq provided");
171 return irq;
172 }
173 res_mem = platform_get_resource(dev, IORESOURCE_MEM, 0);
174 if (!res_mem) {
175 dev_err(&dev->dev, "no memory resource provided");
176 return -ENXIO;
177 }
178
179 hcd = usb_create_hcd(&ehci_platform_hc_driver, &dev->dev,
180 dev_name(&dev->dev));
181 if (!hcd)
182 return -ENOMEM;
183
184 platform_set_drvdata(dev, hcd);
185 dev->dev.platform_data = pdata;
186 priv = hcd_to_ehci_priv(hcd);
187 ehci = hcd_to_ehci(hcd);
188
189 priv->phy = devm_phy_get(&dev->dev, "usb");
190 if (IS_ERR(priv->phy)) {
191 err = PTR_ERR(priv->phy);
192 goto err_put_hcd;
193 }
194
195 for (clk = 0; clk < USB_MAX_CLKS; clk++) {
196 priv->clks[clk] = of_clk_get(dev->dev.of_node, clk);
197 if (IS_ERR(priv->clks[clk])) {
198 err = PTR_ERR(priv->clks[clk]);
199 if (err == -EPROBE_DEFER)
200 goto err_put_clks;
201 priv->clks[clk] = NULL;
202 break;
203 }
204 }
205
206 /* some SoCs don't have a dedicated 48Mhz clock, but those that
207 do need the rate to be explicitly set */
208 priv->clk48 = devm_clk_get(&dev->dev, "clk48");
209 if (IS_ERR(priv->clk48)) {
210 dev_info(&dev->dev, "48MHz clk not found\n");
211 priv->clk48 = NULL;
212 }
213
214 priv->pwr = devm_reset_control_get_optional(&dev->dev, "power");
215 if (IS_ERR(priv->pwr)) {
216 err = PTR_ERR(priv->pwr);
217 if (err == -EPROBE_DEFER)
218 goto err_put_clks;
219 priv->pwr = NULL;
220 }
221
222 priv->rst = devm_reset_control_get_optional(&dev->dev, "softreset");
223 if (IS_ERR(priv->rst)) {
224 err = PTR_ERR(priv->rst);
225 if (err == -EPROBE_DEFER)
226 goto err_put_clks;
227 priv->rst = NULL;
228 }
229
230 if (pdata->power_on) {
231 err = pdata->power_on(dev);
232 if (err < 0)
233 goto err_put_clks;
234 }
235
236 hcd->rsrc_start = res_mem->start;
237 hcd->rsrc_len = resource_size(res_mem);
238
239 hcd->regs = devm_ioremap_resource(&dev->dev, res_mem);
240 if (IS_ERR(hcd->regs)) {
241 err = PTR_ERR(hcd->regs);
242 goto err_put_clks;
243 }
244
245 err = usb_add_hcd(hcd, irq, IRQF_SHARED);
246 if (err)
247 goto err_put_clks;
248
249 device_wakeup_enable(hcd->self.controller);
250 platform_set_drvdata(dev, hcd);
251
252 return err;
253
254 err_put_clks:
255 while (--clk >= 0)
256 clk_put(priv->clks[clk]);
257 err_put_hcd:
258 if (pdata == &ehci_platform_defaults)
259 dev->dev.platform_data = NULL;
260
261 usb_put_hcd(hcd);
262
263 return err;
264 }
265
st_ehci_platform_remove(struct platform_device * dev)266 static int st_ehci_platform_remove(struct platform_device *dev)
267 {
268 struct usb_hcd *hcd = platform_get_drvdata(dev);
269 struct usb_ehci_pdata *pdata = dev_get_platdata(&dev->dev);
270 struct st_ehci_platform_priv *priv = hcd_to_ehci_priv(hcd);
271 int clk;
272
273 usb_remove_hcd(hcd);
274
275 if (pdata->power_off)
276 pdata->power_off(dev);
277
278 for (clk = 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++)
279 clk_put(priv->clks[clk]);
280
281 usb_put_hcd(hcd);
282
283 if (pdata == &ehci_platform_defaults)
284 dev->dev.platform_data = NULL;
285
286 return 0;
287 }
288
289 #ifdef CONFIG_PM_SLEEP
290
st_ehci_suspend(struct device * dev)291 static int st_ehci_suspend(struct device *dev)
292 {
293 struct usb_hcd *hcd = dev_get_drvdata(dev);
294 struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
295 struct platform_device *pdev =
296 container_of(dev, struct platform_device, dev);
297 bool do_wakeup = device_may_wakeup(dev);
298 int ret;
299
300 ret = ehci_suspend(hcd, do_wakeup);
301 if (ret)
302 return ret;
303
304 if (pdata->power_suspend)
305 pdata->power_suspend(pdev);
306
307 pinctrl_pm_select_sleep_state(dev);
308
309 return ret;
310 }
311
st_ehci_resume(struct device * dev)312 static int st_ehci_resume(struct device *dev)
313 {
314 struct usb_hcd *hcd = dev_get_drvdata(dev);
315 struct usb_ehci_pdata *pdata = dev_get_platdata(dev);
316 struct platform_device *pdev =
317 container_of(dev, struct platform_device, dev);
318 int err;
319
320 pinctrl_pm_select_default_state(dev);
321
322 if (pdata->power_on) {
323 err = pdata->power_on(pdev);
324 if (err < 0)
325 return err;
326 }
327
328 ehci_resume(hcd, false);
329 return 0;
330 }
331
332 static SIMPLE_DEV_PM_OPS(st_ehci_pm_ops, st_ehci_suspend, st_ehci_resume);
333
334 #endif /* CONFIG_PM_SLEEP */
335
336 static const struct of_device_id st_ehci_ids[] = {
337 { .compatible = "st,st-ehci-300x", },
338 { /* sentinel */ }
339 };
340 MODULE_DEVICE_TABLE(of, st_ehci_ids);
341
342 static struct platform_driver ehci_platform_driver = {
343 .probe = st_ehci_platform_probe,
344 .remove = st_ehci_platform_remove,
345 .shutdown = usb_hcd_platform_shutdown,
346 .driver = {
347 .name = "st-ehci",
348 #ifdef CONFIG_PM_SLEEP
349 .pm = &st_ehci_pm_ops,
350 #endif
351 .of_match_table = st_ehci_ids,
352 }
353 };
354
ehci_platform_init(void)355 static int __init ehci_platform_init(void)
356 {
357 if (usb_disabled())
358 return -ENODEV;
359
360 pr_info("%s: " DRIVER_DESC "\n", hcd_name);
361
362 ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides);
363 return platform_driver_register(&ehci_platform_driver);
364 }
365 module_init(ehci_platform_init);
366
ehci_platform_cleanup(void)367 static void __exit ehci_platform_cleanup(void)
368 {
369 platform_driver_unregister(&ehci_platform_driver);
370 }
371 module_exit(ehci_platform_cleanup);
372
373 MODULE_DESCRIPTION(DRIVER_DESC);
374 MODULE_AUTHOR("Peter Griffin <peter.griffin@linaro.org>");
375 MODULE_LICENSE("GPL");
376