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.h>
14 #include <linux/of_platform.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 
18 #include "core.h"
19 
20 /* USB wakeup registers */
21 #define USB_WAKEUP_CTRL			0x00
22 
23 /* Global wakeup interrupt enable, also used to clear interrupt */
24 #define USB_WAKEUP_EN			BIT(31)
25 /* Wakeup from connect or disconnect, only for superspeed */
26 #define USB_WAKEUP_SS_CONN		BIT(5)
27 /* 0 select vbus_valid, 1 select sessvld */
28 #define USB_WAKEUP_VBUS_SRC_SESS_VAL	BIT(4)
29 /* Enable signal for wake up from u3 state */
30 #define USB_WAKEUP_U3_EN		BIT(3)
31 /* Enable signal for wake up from id change */
32 #define USB_WAKEUP_ID_EN		BIT(2)
33 /* Enable signal for wake up from vbus change */
34 #define	USB_WAKEUP_VBUS_EN		BIT(1)
35 /* Enable signal for wake up from dp/dm change */
36 #define USB_WAKEUP_DPDM_EN		BIT(0)
37 
38 #define USB_WAKEUP_EN_MASK		GENMASK(5, 0)
39 
40 /* USB glue registers */
41 #define USB_CTRL0		0x00
42 #define USB_CTRL1		0x04
43 
44 #define USB_CTRL0_PORTPWR_EN	BIT(12) /* 1 - PPC enabled (default) */
45 #define USB_CTRL0_USB3_FIXED	BIT(22) /* 1 - USB3 permanent attached */
46 #define USB_CTRL0_USB2_FIXED	BIT(23) /* 1 - USB2 permanent attached */
47 
48 #define USB_CTRL1_OC_POLARITY	BIT(16) /* 0 - HIGH / 1 - LOW */
49 #define USB_CTRL1_PWR_POLARITY	BIT(17) /* 0 - HIGH / 1 - LOW */
50 
51 struct dwc3_imx8mp {
52 	struct device			*dev;
53 	struct platform_device		*dwc3;
54 	void __iomem			*hsio_blk_base;
55 	void __iomem			*glue_base;
56 	struct clk			*hsio_clk;
57 	struct clk			*suspend_clk;
58 	int				irq;
59 	bool				pm_suspended;
60 	bool				wakeup_pending;
61 };
62 
imx8mp_configure_glue(struct dwc3_imx8mp * dwc3_imx)63 static void imx8mp_configure_glue(struct dwc3_imx8mp *dwc3_imx)
64 {
65 	struct device *dev = dwc3_imx->dev;
66 	u32 value;
67 
68 	if (!dwc3_imx->glue_base)
69 		return;
70 
71 	value = readl(dwc3_imx->glue_base + USB_CTRL0);
72 
73 	if (device_property_read_bool(dev, "fsl,permanently-attached"))
74 		value |= (USB_CTRL0_USB2_FIXED | USB_CTRL0_USB3_FIXED);
75 	else
76 		value &= ~(USB_CTRL0_USB2_FIXED | USB_CTRL0_USB3_FIXED);
77 
78 	if (device_property_read_bool(dev, "fsl,disable-port-power-control"))
79 		value &= ~(USB_CTRL0_PORTPWR_EN);
80 	else
81 		value |= USB_CTRL0_PORTPWR_EN;
82 
83 	writel(value, dwc3_imx->glue_base + USB_CTRL0);
84 
85 	value = readl(dwc3_imx->glue_base + USB_CTRL1);
86 	if (device_property_read_bool(dev, "fsl,over-current-active-low"))
87 		value |= USB_CTRL1_OC_POLARITY;
88 	else
89 		value &= ~USB_CTRL1_OC_POLARITY;
90 
91 	if (device_property_read_bool(dev, "fsl,power-active-low"))
92 		value |= USB_CTRL1_PWR_POLARITY;
93 	else
94 		value &= ~USB_CTRL1_PWR_POLARITY;
95 
96 	writel(value, dwc3_imx->glue_base + USB_CTRL1);
97 }
98 
dwc3_imx8mp_wakeup_enable(struct dwc3_imx8mp * dwc3_imx)99 static void dwc3_imx8mp_wakeup_enable(struct dwc3_imx8mp *dwc3_imx)
100 {
101 	struct dwc3	*dwc3 = platform_get_drvdata(dwc3_imx->dwc3);
102 	u32		val;
103 
104 	if (!dwc3)
105 		return;
106 
107 	val = readl(dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);
108 
109 	if ((dwc3->current_dr_role == DWC3_GCTL_PRTCAP_HOST) && dwc3->xhci)
110 		val |= USB_WAKEUP_EN | USB_WAKEUP_SS_CONN |
111 		       USB_WAKEUP_U3_EN | USB_WAKEUP_DPDM_EN;
112 	else if (dwc3->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE)
113 		val |= USB_WAKEUP_EN | USB_WAKEUP_VBUS_EN |
114 		       USB_WAKEUP_VBUS_SRC_SESS_VAL;
115 
116 	writel(val, dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);
117 }
118 
dwc3_imx8mp_wakeup_disable(struct dwc3_imx8mp * dwc3_imx)119 static void dwc3_imx8mp_wakeup_disable(struct dwc3_imx8mp *dwc3_imx)
120 {
121 	u32 val;
122 
123 	val = readl(dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);
124 	val &= ~(USB_WAKEUP_EN | USB_WAKEUP_EN_MASK);
125 	writel(val, dwc3_imx->hsio_blk_base + USB_WAKEUP_CTRL);
126 }
127 
dwc3_imx8mp_interrupt(int irq,void * _dwc3_imx)128 static irqreturn_t dwc3_imx8mp_interrupt(int irq, void *_dwc3_imx)
129 {
130 	struct dwc3_imx8mp	*dwc3_imx = _dwc3_imx;
131 	struct dwc3		*dwc = platform_get_drvdata(dwc3_imx->dwc3);
132 
133 	if (!dwc3_imx->pm_suspended)
134 		return IRQ_HANDLED;
135 
136 	disable_irq_nosync(dwc3_imx->irq);
137 	dwc3_imx->wakeup_pending = true;
138 
139 	if ((dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST) && dwc->xhci)
140 		pm_runtime_resume(&dwc->xhci->dev);
141 	else if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE)
142 		pm_runtime_get(dwc->dev);
143 
144 	return IRQ_HANDLED;
145 }
146 
dwc3_imx8mp_probe(struct platform_device * pdev)147 static int dwc3_imx8mp_probe(struct platform_device *pdev)
148 {
149 	struct device		*dev = &pdev->dev;
150 	struct device_node	*dwc3_np, *node = dev->of_node;
151 	struct dwc3_imx8mp	*dwc3_imx;
152 	struct resource		*res;
153 	int			err, irq;
154 
155 	if (!node) {
156 		dev_err(dev, "device node not found\n");
157 		return -EINVAL;
158 	}
159 
160 	dwc3_imx = devm_kzalloc(dev, sizeof(*dwc3_imx), GFP_KERNEL);
161 	if (!dwc3_imx)
162 		return -ENOMEM;
163 
164 	platform_set_drvdata(pdev, dwc3_imx);
165 
166 	dwc3_imx->dev = dev;
167 
168 	dwc3_imx->hsio_blk_base = devm_platform_ioremap_resource(pdev, 0);
169 	if (IS_ERR(dwc3_imx->hsio_blk_base))
170 		return PTR_ERR(dwc3_imx->hsio_blk_base);
171 
172 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
173 	if (!res) {
174 		dev_warn(dev, "Base address for glue layer missing. Continuing without, some features are missing though.");
175 	} else {
176 		dwc3_imx->glue_base = devm_ioremap_resource(dev, res);
177 		if (IS_ERR(dwc3_imx->glue_base))
178 			return PTR_ERR(dwc3_imx->glue_base);
179 	}
180 
181 	dwc3_imx->hsio_clk = devm_clk_get(dev, "hsio");
182 	if (IS_ERR(dwc3_imx->hsio_clk)) {
183 		err = PTR_ERR(dwc3_imx->hsio_clk);
184 		dev_err(dev, "Failed to get hsio clk, err=%d\n", err);
185 		return err;
186 	}
187 
188 	err = clk_prepare_enable(dwc3_imx->hsio_clk);
189 	if (err) {
190 		dev_err(dev, "Failed to enable hsio clk, err=%d\n", err);
191 		return err;
192 	}
193 
194 	dwc3_imx->suspend_clk = devm_clk_get(dev, "suspend");
195 	if (IS_ERR(dwc3_imx->suspend_clk)) {
196 		err = PTR_ERR(dwc3_imx->suspend_clk);
197 		dev_err(dev, "Failed to get suspend clk, err=%d\n", err);
198 		goto disable_hsio_clk;
199 	}
200 
201 	err = clk_prepare_enable(dwc3_imx->suspend_clk);
202 	if (err) {
203 		dev_err(dev, "Failed to enable suspend clk, err=%d\n", err);
204 		goto disable_hsio_clk;
205 	}
206 
207 	irq = platform_get_irq(pdev, 0);
208 	if (irq < 0) {
209 		err = irq;
210 		goto disable_clks;
211 	}
212 	dwc3_imx->irq = irq;
213 
214 	imx8mp_configure_glue(dwc3_imx);
215 
216 	pm_runtime_set_active(dev);
217 	pm_runtime_enable(dev);
218 	err = pm_runtime_get_sync(dev);
219 	if (err < 0)
220 		goto disable_rpm;
221 
222 	dwc3_np = of_get_compatible_child(node, "snps,dwc3");
223 	if (!dwc3_np) {
224 		err = -ENODEV;
225 		dev_err(dev, "failed to find dwc3 core child\n");
226 		goto disable_rpm;
227 	}
228 
229 	err = of_platform_populate(node, NULL, NULL, dev);
230 	if (err) {
231 		dev_err(&pdev->dev, "failed to create dwc3 core\n");
232 		goto err_node_put;
233 	}
234 
235 	dwc3_imx->dwc3 = of_find_device_by_node(dwc3_np);
236 	if (!dwc3_imx->dwc3) {
237 		dev_err(dev, "failed to get dwc3 platform device\n");
238 		err = -ENODEV;
239 		goto depopulate;
240 	}
241 	of_node_put(dwc3_np);
242 
243 	err = devm_request_threaded_irq(dev, irq, NULL, dwc3_imx8mp_interrupt,
244 					IRQF_ONESHOT, dev_name(dev), dwc3_imx);
245 	if (err) {
246 		dev_err(dev, "failed to request IRQ #%d --> %d\n", irq, err);
247 		goto depopulate;
248 	}
249 
250 	device_set_wakeup_capable(dev, true);
251 	pm_runtime_put(dev);
252 
253 	return 0;
254 
255 depopulate:
256 	of_platform_depopulate(dev);
257 err_node_put:
258 	of_node_put(dwc3_np);
259 disable_rpm:
260 	pm_runtime_disable(dev);
261 	pm_runtime_put_noidle(dev);
262 disable_clks:
263 	clk_disable_unprepare(dwc3_imx->suspend_clk);
264 disable_hsio_clk:
265 	clk_disable_unprepare(dwc3_imx->hsio_clk);
266 
267 	return err;
268 }
269 
dwc3_imx8mp_remove(struct platform_device * pdev)270 static void dwc3_imx8mp_remove(struct platform_device *pdev)
271 {
272 	struct dwc3_imx8mp *dwc3_imx = platform_get_drvdata(pdev);
273 	struct device *dev = &pdev->dev;
274 
275 	pm_runtime_get_sync(dev);
276 	of_platform_depopulate(dev);
277 
278 	clk_disable_unprepare(dwc3_imx->suspend_clk);
279 	clk_disable_unprepare(dwc3_imx->hsio_clk);
280 
281 	pm_runtime_disable(dev);
282 	pm_runtime_put_noidle(dev);
283 }
284 
dwc3_imx8mp_suspend(struct dwc3_imx8mp * dwc3_imx,pm_message_t msg)285 static int __maybe_unused dwc3_imx8mp_suspend(struct dwc3_imx8mp *dwc3_imx,
286 					      pm_message_t msg)
287 {
288 	if (dwc3_imx->pm_suspended)
289 		return 0;
290 
291 	/* Wakeup enable */
292 	if (PMSG_IS_AUTO(msg) || device_may_wakeup(dwc3_imx->dev))
293 		dwc3_imx8mp_wakeup_enable(dwc3_imx);
294 
295 	dwc3_imx->pm_suspended = true;
296 
297 	return 0;
298 }
299 
dwc3_imx8mp_resume(struct dwc3_imx8mp * dwc3_imx,pm_message_t msg)300 static int __maybe_unused dwc3_imx8mp_resume(struct dwc3_imx8mp *dwc3_imx,
301 					     pm_message_t msg)
302 {
303 	struct dwc3	*dwc = platform_get_drvdata(dwc3_imx->dwc3);
304 	int ret = 0;
305 
306 	if (!dwc3_imx->pm_suspended)
307 		return 0;
308 
309 	/* Wakeup disable */
310 	dwc3_imx8mp_wakeup_disable(dwc3_imx);
311 	dwc3_imx->pm_suspended = false;
312 
313 	/* Upon power loss any previous configuration is lost, restore it */
314 	imx8mp_configure_glue(dwc3_imx);
315 
316 	if (dwc3_imx->wakeup_pending) {
317 		dwc3_imx->wakeup_pending = false;
318 		if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE) {
319 			pm_runtime_mark_last_busy(dwc->dev);
320 			pm_runtime_put_autosuspend(dwc->dev);
321 		} else {
322 			/*
323 			 * Add wait for xhci switch from suspend
324 			 * clock to normal clock to detect connection.
325 			 */
326 			usleep_range(9000, 10000);
327 		}
328 		enable_irq(dwc3_imx->irq);
329 	}
330 
331 	return ret;
332 }
333 
dwc3_imx8mp_pm_suspend(struct device * dev)334 static int __maybe_unused dwc3_imx8mp_pm_suspend(struct device *dev)
335 {
336 	struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
337 	int ret;
338 
339 	ret = dwc3_imx8mp_suspend(dwc3_imx, PMSG_SUSPEND);
340 
341 	if (device_may_wakeup(dwc3_imx->dev))
342 		enable_irq_wake(dwc3_imx->irq);
343 	else
344 		clk_disable_unprepare(dwc3_imx->suspend_clk);
345 
346 	clk_disable_unprepare(dwc3_imx->hsio_clk);
347 	dev_dbg(dev, "dwc3 imx8mp pm suspend.\n");
348 
349 	return ret;
350 }
351 
dwc3_imx8mp_pm_resume(struct device * dev)352 static int __maybe_unused dwc3_imx8mp_pm_resume(struct device *dev)
353 {
354 	struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
355 	int ret;
356 
357 	if (device_may_wakeup(dwc3_imx->dev)) {
358 		disable_irq_wake(dwc3_imx->irq);
359 	} else {
360 		ret = clk_prepare_enable(dwc3_imx->suspend_clk);
361 		if (ret)
362 			return ret;
363 	}
364 
365 	ret = clk_prepare_enable(dwc3_imx->hsio_clk);
366 	if (ret)
367 		return ret;
368 
369 	ret = dwc3_imx8mp_resume(dwc3_imx, PMSG_RESUME);
370 
371 	pm_runtime_disable(dev);
372 	pm_runtime_set_active(dev);
373 	pm_runtime_enable(dev);
374 
375 	dev_dbg(dev, "dwc3 imx8mp pm resume.\n");
376 
377 	return ret;
378 }
379 
dwc3_imx8mp_runtime_suspend(struct device * dev)380 static int __maybe_unused dwc3_imx8mp_runtime_suspend(struct device *dev)
381 {
382 	struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
383 
384 	dev_dbg(dev, "dwc3 imx8mp runtime suspend.\n");
385 
386 	return dwc3_imx8mp_suspend(dwc3_imx, PMSG_AUTO_SUSPEND);
387 }
388 
dwc3_imx8mp_runtime_resume(struct device * dev)389 static int __maybe_unused dwc3_imx8mp_runtime_resume(struct device *dev)
390 {
391 	struct dwc3_imx8mp *dwc3_imx = dev_get_drvdata(dev);
392 
393 	dev_dbg(dev, "dwc3 imx8mp runtime resume.\n");
394 
395 	return dwc3_imx8mp_resume(dwc3_imx, PMSG_AUTO_RESUME);
396 }
397 
398 static const struct dev_pm_ops dwc3_imx8mp_dev_pm_ops = {
399 	SET_SYSTEM_SLEEP_PM_OPS(dwc3_imx8mp_pm_suspend, dwc3_imx8mp_pm_resume)
400 	SET_RUNTIME_PM_OPS(dwc3_imx8mp_runtime_suspend,
401 			   dwc3_imx8mp_runtime_resume, NULL)
402 };
403 
404 static const struct of_device_id dwc3_imx8mp_of_match[] = {
405 	{ .compatible = "fsl,imx8mp-dwc3", },
406 	{},
407 };
408 MODULE_DEVICE_TABLE(of, dwc3_imx8mp_of_match);
409 
410 static struct platform_driver dwc3_imx8mp_driver = {
411 	.probe		= dwc3_imx8mp_probe,
412 	.remove_new	= dwc3_imx8mp_remove,
413 	.driver		= {
414 		.name	= "imx8mp-dwc3",
415 		.pm	= &dwc3_imx8mp_dev_pm_ops,
416 		.of_match_table	= dwc3_imx8mp_of_match,
417 	},
418 };
419 
420 module_platform_driver(dwc3_imx8mp_driver);
421 
422 MODULE_ALIAS("platform:imx8mp-dwc3");
423 MODULE_AUTHOR("jun.li@nxp.com");
424 MODULE_LICENSE("GPL v2");
425 MODULE_DESCRIPTION("DesignWare USB3 imx8mp Glue Layer");
426