1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * dwc3-imx8mp.c - NXP imx8mp Specific Glue layer
4  *
5  * Copyright (c) 2020 NXP.
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/interrupt.h>
10 #include <linux/io.h>
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/of_platform.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm_runtime.h>
16 
17 #include "core.h"
18 
19 /* USB wakeup registers */
20 #define USB_WAKEUP_CTRL			0x00
21 
22 /* Global wakeup interrupt enable, also used to clear interrupt */
23 #define USB_WAKEUP_EN			BIT(31)
24 /* Wakeup from connect or disconnect, only for superspeed */
25 #define USB_WAKEUP_SS_CONN		BIT(5)
26 /* 0 select vbus_valid, 1 select sessvld */
27 #define USB_WAKEUP_VBUS_SRC_SESS_VAL	BIT(4)
28 /* Enable signal for wake up from u3 state */
29 #define USB_WAKEUP_U3_EN		BIT(3)
30 /* Enable signal for wake up from id change */
31 #define USB_WAKEUP_ID_EN		BIT(2)
32 /* Enable signal for wake up from vbus change */
33 #define	USB_WAKEUP_VBUS_EN		BIT(1)
34 /* Enable signal for wake up from dp/dm change */
35 #define USB_WAKEUP_DPDM_EN		BIT(0)
36 
37 #define USB_WAKEUP_EN_MASK		GENMASK(5, 0)
38 
39 struct dwc3_imx8mp {
40 	struct device			*dev;
41 	struct platform_device		*dwc3;
42 	void __iomem			*glue_base;
43 	struct clk			*hsio_clk;
44 	struct clk			*suspend_clk;
45 	int				irq;
46 	bool				pm_suspended;
47 	bool				wakeup_pending;
48 };
49 
dwc3_imx8mp_wakeup_enable(struct dwc3_imx8mp * dwc3_imx)50 static void dwc3_imx8mp_wakeup_enable(struct dwc3_imx8mp *dwc3_imx)
51 {
52 	struct dwc3	*dwc3 = platform_get_drvdata(dwc3_imx->dwc3);
53 	u32		val;
54 
55 	if (!dwc3)
56 		return;
57 
58 	val = readl(dwc3_imx->glue_base + USB_WAKEUP_CTRL);
59 
60 	if ((dwc3->current_dr_role == DWC3_GCTL_PRTCAP_HOST) && dwc3->xhci)
61 		val |= USB_WAKEUP_EN | USB_WAKEUP_SS_CONN |
62 		       USB_WAKEUP_U3_EN | USB_WAKEUP_DPDM_EN;
63 	else if (dwc3->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE)
64 		val |= USB_WAKEUP_EN | USB_WAKEUP_VBUS_EN |
65 		       USB_WAKEUP_VBUS_SRC_SESS_VAL;
66 
67 	writel(val, dwc3_imx->glue_base + USB_WAKEUP_CTRL);
68 }
69 
dwc3_imx8mp_wakeup_disable(struct dwc3_imx8mp * dwc3_imx)70 static void dwc3_imx8mp_wakeup_disable(struct dwc3_imx8mp *dwc3_imx)
71 {
72 	u32 val;
73 
74 	val = readl(dwc3_imx->glue_base + USB_WAKEUP_CTRL);
75 	val &= ~(USB_WAKEUP_EN | USB_WAKEUP_EN_MASK);
76 	writel(val, dwc3_imx->glue_base + USB_WAKEUP_CTRL);
77 }
78 
dwc3_imx8mp_interrupt(int irq,void * _dwc3_imx)79 static irqreturn_t dwc3_imx8mp_interrupt(int irq, void *_dwc3_imx)
80 {
81 	struct dwc3_imx8mp	*dwc3_imx = _dwc3_imx;
82 	struct dwc3		*dwc = platform_get_drvdata(dwc3_imx->dwc3);
83 
84 	if (!dwc3_imx->pm_suspended)
85 		return IRQ_HANDLED;
86 
87 	disable_irq_nosync(dwc3_imx->irq);
88 	dwc3_imx->wakeup_pending = true;
89 
90 	if ((dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST) && dwc->xhci)
91 		pm_runtime_resume(&dwc->xhci->dev);
92 	else if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE)
93 		pm_runtime_get(dwc->dev);
94 
95 	return IRQ_HANDLED;
96 }
97 
dwc3_imx8mp_probe(struct platform_device * pdev)98 static int dwc3_imx8mp_probe(struct platform_device *pdev)
99 {
100 	struct device		*dev = &pdev->dev;
101 	struct device_node	*dwc3_np, *node = dev->of_node;
102 	struct dwc3_imx8mp	*dwc3_imx;
103 	int			err, irq;
104 
105 	if (!node) {
106 		dev_err(dev, "device node not found\n");
107 		return -EINVAL;
108 	}
109 
110 	dwc3_imx = devm_kzalloc(dev, sizeof(*dwc3_imx), GFP_KERNEL);
111 	if (!dwc3_imx)
112 		return -ENOMEM;
113 
114 	platform_set_drvdata(pdev, dwc3_imx);
115 
116 	dwc3_imx->dev = dev;
117 
118 	dwc3_imx->glue_base = devm_platform_ioremap_resource(pdev, 0);
119 	if (IS_ERR(dwc3_imx->glue_base))
120 		return PTR_ERR(dwc3_imx->glue_base);
121 
122 	dwc3_imx->hsio_clk = devm_clk_get(dev, "hsio");
123 	if (IS_ERR(dwc3_imx->hsio_clk)) {
124 		err = PTR_ERR(dwc3_imx->hsio_clk);
125 		dev_err(dev, "Failed to get hsio clk, err=%d\n", err);
126 		return err;
127 	}
128 
129 	err = clk_prepare_enable(dwc3_imx->hsio_clk);
130 	if (err) {
131 		dev_err(dev, "Failed to enable hsio clk, err=%d\n", err);
132 		return err;
133 	}
134 
135 	dwc3_imx->suspend_clk = devm_clk_get(dev, "suspend");
136 	if (IS_ERR(dwc3_imx->suspend_clk)) {
137 		err = PTR_ERR(dwc3_imx->suspend_clk);
138 		dev_err(dev, "Failed to get suspend clk, err=%d\n", err);
139 		goto disable_hsio_clk;
140 	}
141 
142 	err = clk_prepare_enable(dwc3_imx->suspend_clk);
143 	if (err) {
144 		dev_err(dev, "Failed to enable suspend clk, err=%d\n", err);
145 		goto disable_hsio_clk;
146 	}
147 
148 	irq = platform_get_irq(pdev, 0);
149 	if (irq < 0) {
150 		err = irq;
151 		goto disable_clks;
152 	}
153 	dwc3_imx->irq = irq;
154 
155 	pm_runtime_set_active(dev);
156 	pm_runtime_enable(dev);
157 	err = pm_runtime_get_sync(dev);
158 	if (err < 0)
159 		goto disable_rpm;
160 
161 	dwc3_np = of_get_compatible_child(node, "snps,dwc3");
162 	if (!dwc3_np) {
163 		err = -ENODEV;
164 		dev_err(dev, "failed to find dwc3 core child\n");
165 		goto disable_rpm;
166 	}
167 
168 	err = of_platform_populate(node, NULL, NULL, dev);
169 	if (err) {
170 		dev_err(&pdev->dev, "failed to create dwc3 core\n");
171 		goto err_node_put;
172 	}
173 
174 	dwc3_imx->dwc3 = of_find_device_by_node(dwc3_np);
175 	if (!dwc3_imx->dwc3) {
176 		dev_err(dev, "failed to get dwc3 platform device\n");
177 		err = -ENODEV;
178 		goto depopulate;
179 	}
180 	of_node_put(dwc3_np);
181 
182 	err = devm_request_threaded_irq(dev, irq, NULL, dwc3_imx8mp_interrupt,
183 					IRQF_ONESHOT, dev_name(dev), dwc3_imx);
184 	if (err) {
185 		dev_err(dev, "failed to request IRQ #%d --> %d\n", irq, err);
186 		goto depopulate;
187 	}
188 
189 	device_set_wakeup_capable(dev, true);
190 	pm_runtime_put(dev);
191 
192 	return 0;
193 
194 depopulate:
195 	of_platform_depopulate(dev);
196 err_node_put:
197 	of_node_put(dwc3_np);
198 disable_rpm:
199 	pm_runtime_disable(dev);
200 	pm_runtime_put_noidle(dev);
201 disable_clks:
202 	clk_disable_unprepare(dwc3_imx->suspend_clk);
203 disable_hsio_clk:
204 	clk_disable_unprepare(dwc3_imx->hsio_clk);
205 
206 	return err;
207 }
208 
dwc3_imx8mp_remove(struct platform_device * pdev)209 static int dwc3_imx8mp_remove(struct platform_device *pdev)
210 {
211 	struct dwc3_imx8mp *dwc3_imx = platform_get_drvdata(pdev);
212 	struct device *dev = &pdev->dev;
213 
214 	pm_runtime_get_sync(dev);
215 	of_platform_depopulate(dev);
216 
217 	clk_disable_unprepare(dwc3_imx->suspend_clk);
218 	clk_disable_unprepare(dwc3_imx->hsio_clk);
219 
220 	pm_runtime_disable(dev);
221 	pm_runtime_put_noidle(dev);
222 	platform_set_drvdata(pdev, NULL);
223 
224 	return 0;
225 }
226 
dwc3_imx8mp_suspend(struct dwc3_imx8mp * dwc3_imx,pm_message_t msg)227 static int __maybe_unused dwc3_imx8mp_suspend(struct dwc3_imx8mp *dwc3_imx,
228 					      pm_message_t msg)
229 {
230 	if (dwc3_imx->pm_suspended)
231 		return 0;
232 
233 	/* Wakeup enable */
234 	if (PMSG_IS_AUTO(msg) || device_may_wakeup(dwc3_imx->dev))
235 		dwc3_imx8mp_wakeup_enable(dwc3_imx);
236 
237 	dwc3_imx->pm_suspended = true;
238 
239 	return 0;
240 }
241 
dwc3_imx8mp_resume(struct dwc3_imx8mp * dwc3_imx,pm_message_t msg)242 static int __maybe_unused dwc3_imx8mp_resume(struct dwc3_imx8mp *dwc3_imx,
243 					     pm_message_t msg)
244 {
245 	struct dwc3	*dwc = platform_get_drvdata(dwc3_imx->dwc3);
246 	int ret = 0;
247 
248 	if (!dwc3_imx->pm_suspended)
249 		return 0;
250 
251 	/* Wakeup disable */
252 	dwc3_imx8mp_wakeup_disable(dwc3_imx);
253 	dwc3_imx->pm_suspended = false;
254 
255 	if (dwc3_imx->wakeup_pending) {
256 		dwc3_imx->wakeup_pending = false;
257 		if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE) {
258 			pm_runtime_mark_last_busy(dwc->dev);
259 			pm_runtime_put_autosuspend(dwc->dev);
260 		} else {
261 			/*
262 			 * Add wait for xhci switch from suspend
263 			 * clock to normal clock to detect connection.
264 			 */
265 			usleep_range(9000, 10000);
266 		}
267 		enable_irq(dwc3_imx->irq);
268 	}
269 
270 	return ret;
271 }
272 
dwc3_imx8mp_pm_suspend(struct device * dev)273 static int __maybe_unused dwc3_imx8mp_pm_suspend(struct device *dev)
274 {
275 	struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
276 	int ret;
277 
278 	ret = dwc3_imx8mp_suspend(dwc3_imx, PMSG_SUSPEND);
279 
280 	if (device_may_wakeup(dwc3_imx->dev))
281 		enable_irq_wake(dwc3_imx->irq);
282 	else
283 		clk_disable_unprepare(dwc3_imx->suspend_clk);
284 
285 	clk_disable_unprepare(dwc3_imx->hsio_clk);
286 	dev_dbg(dev, "dwc3 imx8mp pm suspend.\n");
287 
288 	return ret;
289 }
290 
dwc3_imx8mp_pm_resume(struct device * dev)291 static int __maybe_unused dwc3_imx8mp_pm_resume(struct device *dev)
292 {
293 	struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
294 	int ret;
295 
296 	if (device_may_wakeup(dwc3_imx->dev)) {
297 		disable_irq_wake(dwc3_imx->irq);
298 	} else {
299 		ret = clk_prepare_enable(dwc3_imx->suspend_clk);
300 		if (ret)
301 			return ret;
302 	}
303 
304 	ret = clk_prepare_enable(dwc3_imx->hsio_clk);
305 	if (ret)
306 		return ret;
307 
308 	ret = dwc3_imx8mp_resume(dwc3_imx, PMSG_RESUME);
309 
310 	pm_runtime_disable(dev);
311 	pm_runtime_set_active(dev);
312 	pm_runtime_enable(dev);
313 
314 	dev_dbg(dev, "dwc3 imx8mp pm resume.\n");
315 
316 	return ret;
317 }
318 
dwc3_imx8mp_runtime_suspend(struct device * dev)319 static int __maybe_unused dwc3_imx8mp_runtime_suspend(struct device *dev)
320 {
321 	struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
322 
323 	dev_dbg(dev, "dwc3 imx8mp runtime suspend.\n");
324 
325 	return dwc3_imx8mp_suspend(dwc3_imx, PMSG_AUTO_SUSPEND);
326 }
327 
dwc3_imx8mp_runtime_resume(struct device * dev)328 static int __maybe_unused dwc3_imx8mp_runtime_resume(struct device *dev)
329 {
330 	struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
331 
332 	dev_dbg(dev, "dwc3 imx8mp runtime resume.\n");
333 
334 	return dwc3_imx8mp_resume(dwc3_imx, PMSG_AUTO_RESUME);
335 }
336 
337 static const struct dev_pm_ops dwc3_imx8mp_dev_pm_ops = {
338 	SET_SYSTEM_SLEEP_PM_OPS(dwc3_imx8mp_pm_suspend, dwc3_imx8mp_pm_resume)
339 	SET_RUNTIME_PM_OPS(dwc3_imx8mp_runtime_suspend,
340 			   dwc3_imx8mp_runtime_resume, NULL)
341 };
342 
343 static const struct of_device_id dwc3_imx8mp_of_match[] = {
344 	{ .compatible = "fsl,imx8mp-dwc3", },
345 	{},
346 };
347 MODULE_DEVICE_TABLE(of, dwc3_imx8mp_of_match);
348 
349 static struct platform_driver dwc3_imx8mp_driver = {
350 	.probe		= dwc3_imx8mp_probe,
351 	.remove		= dwc3_imx8mp_remove,
352 	.driver		= {
353 		.name	= "imx8mp-dwc3",
354 		.pm	= &dwc3_imx8mp_dev_pm_ops,
355 		.of_match_table	= dwc3_imx8mp_of_match,
356 	},
357 };
358 
359 module_platform_driver(dwc3_imx8mp_driver);
360 
361 MODULE_ALIAS("platform:imx8mp-dwc3");
362 MODULE_AUTHOR("jun.li@nxp.com");
363 MODULE_LICENSE("GPL v2");
364 MODULE_DESCRIPTION("DesignWare USB3 imx8mp Glue Layer");
365