1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Renesas R-Car Gen3 for USB2.0 PHY driver
4  *
5  * Copyright (C) 2015-2017 Renesas Electronics Corporation
6  *
7  * This is based on the phy-rcar-gen2 driver:
8  * Copyright (C) 2014 Renesas Solutions Corp.
9  * Copyright (C) 2014 Cogent Embedded, Inc.
10  */
11 
12 #include <linux/extcon-provider.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/of_address.h>
18 #include <linux/of_device.h>
19 #include <linux/phy/phy.h>
20 #include <linux/platform_device.h>
21 #include <linux/pm_runtime.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/usb/of.h>
24 #include <linux/workqueue.h>
25 
26 /******* USB2.0 Host registers (original offset is +0x200) *******/
27 #define USB2_INT_ENABLE		0x000
28 #define USB2_USBCTR		0x00c
29 #define USB2_SPD_RSM_TIMSET	0x10c
30 #define USB2_OC_TIMSET		0x110
31 #define USB2_COMMCTRL		0x600
32 #define USB2_OBINTSTA		0x604
33 #define USB2_OBINTEN		0x608
34 #define USB2_VBCTRL		0x60c
35 #define USB2_LINECTRL1		0x610
36 #define USB2_ADPCTRL		0x630
37 
38 /* INT_ENABLE */
39 #define USB2_INT_ENABLE_UCOM_INTEN	BIT(3)
40 #define USB2_INT_ENABLE_USBH_INTB_EN	BIT(2)
41 #define USB2_INT_ENABLE_USBH_INTA_EN	BIT(1)
42 #define USB2_INT_ENABLE_INIT		(USB2_INT_ENABLE_UCOM_INTEN | \
43 					 USB2_INT_ENABLE_USBH_INTB_EN | \
44 					 USB2_INT_ENABLE_USBH_INTA_EN)
45 
46 /* USBCTR */
47 #define USB2_USBCTR_DIRPD	BIT(2)
48 #define USB2_USBCTR_PLL_RST	BIT(1)
49 
50 /* SPD_RSM_TIMSET */
51 #define USB2_SPD_RSM_TIMSET_INIT	0x014e029b
52 
53 /* OC_TIMSET */
54 #define USB2_OC_TIMSET_INIT		0x000209ab
55 
56 /* COMMCTRL */
57 #define USB2_COMMCTRL_OTG_PERI		BIT(31)	/* 1 = Peripheral mode */
58 
59 /* OBINTSTA and OBINTEN */
60 #define USB2_OBINT_SESSVLDCHG		BIT(12)
61 #define USB2_OBINT_IDDIGCHG		BIT(11)
62 #define USB2_OBINT_BITS			(USB2_OBINT_SESSVLDCHG | \
63 					 USB2_OBINT_IDDIGCHG)
64 
65 /* VBCTRL */
66 #define USB2_VBCTRL_DRVVBUSSEL		BIT(8)
67 
68 /* LINECTRL1 */
69 #define USB2_LINECTRL1_DPRPD_EN		BIT(19)
70 #define USB2_LINECTRL1_DP_RPD		BIT(18)
71 #define USB2_LINECTRL1_DMRPD_EN		BIT(17)
72 #define USB2_LINECTRL1_DM_RPD		BIT(16)
73 #define USB2_LINECTRL1_OPMODE_NODRV	BIT(6)
74 
75 /* ADPCTRL */
76 #define USB2_ADPCTRL_OTGSESSVLD		BIT(20)
77 #define USB2_ADPCTRL_IDDIG		BIT(19)
78 #define USB2_ADPCTRL_IDPULLUP		BIT(5)	/* 1 = ID sampling is enabled */
79 #define USB2_ADPCTRL_DRVVBUS		BIT(4)
80 
81 #define RCAR_GEN3_PHY_HAS_DEDICATED_PINS	1
82 
83 struct rcar_gen3_chan {
84 	void __iomem *base;
85 	struct extcon_dev *extcon;
86 	struct phy *phy;
87 	struct regulator *vbus;
88 	struct work_struct work;
89 	bool extcon_host;
90 	bool has_otg_pins;
91 };
92 
93 static void rcar_gen3_phy_usb2_work(struct work_struct *work)
94 {
95 	struct rcar_gen3_chan *ch = container_of(work, struct rcar_gen3_chan,
96 						 work);
97 
98 	if (ch->extcon_host) {
99 		extcon_set_state_sync(ch->extcon, EXTCON_USB_HOST, true);
100 		extcon_set_state_sync(ch->extcon, EXTCON_USB, false);
101 	} else {
102 		extcon_set_state_sync(ch->extcon, EXTCON_USB_HOST, false);
103 		extcon_set_state_sync(ch->extcon, EXTCON_USB, true);
104 	}
105 }
106 
107 static void rcar_gen3_set_host_mode(struct rcar_gen3_chan *ch, int host)
108 {
109 	void __iomem *usb2_base = ch->base;
110 	u32 val = readl(usb2_base + USB2_COMMCTRL);
111 
112 	dev_vdbg(&ch->phy->dev, "%s: %08x, %d\n", __func__, val, host);
113 	if (host)
114 		val &= ~USB2_COMMCTRL_OTG_PERI;
115 	else
116 		val |= USB2_COMMCTRL_OTG_PERI;
117 	writel(val, usb2_base + USB2_COMMCTRL);
118 }
119 
120 static void rcar_gen3_set_linectrl(struct rcar_gen3_chan *ch, int dp, int dm)
121 {
122 	void __iomem *usb2_base = ch->base;
123 	u32 val = readl(usb2_base + USB2_LINECTRL1);
124 
125 	dev_vdbg(&ch->phy->dev, "%s: %08x, %d, %d\n", __func__, val, dp, dm);
126 	val &= ~(USB2_LINECTRL1_DP_RPD | USB2_LINECTRL1_DM_RPD);
127 	if (dp)
128 		val |= USB2_LINECTRL1_DP_RPD;
129 	if (dm)
130 		val |= USB2_LINECTRL1_DM_RPD;
131 	writel(val, usb2_base + USB2_LINECTRL1);
132 }
133 
134 static void rcar_gen3_enable_vbus_ctrl(struct rcar_gen3_chan *ch, int vbus)
135 {
136 	void __iomem *usb2_base = ch->base;
137 	u32 val = readl(usb2_base + USB2_ADPCTRL);
138 
139 	dev_vdbg(&ch->phy->dev, "%s: %08x, %d\n", __func__, val, vbus);
140 	if (vbus)
141 		val |= USB2_ADPCTRL_DRVVBUS;
142 	else
143 		val &= ~USB2_ADPCTRL_DRVVBUS;
144 	writel(val, usb2_base + USB2_ADPCTRL);
145 }
146 
147 static void rcar_gen3_init_for_host(struct rcar_gen3_chan *ch)
148 {
149 	rcar_gen3_set_linectrl(ch, 1, 1);
150 	rcar_gen3_set_host_mode(ch, 1);
151 	rcar_gen3_enable_vbus_ctrl(ch, 1);
152 
153 	ch->extcon_host = true;
154 	schedule_work(&ch->work);
155 }
156 
157 static void rcar_gen3_init_for_peri(struct rcar_gen3_chan *ch)
158 {
159 	rcar_gen3_set_linectrl(ch, 0, 1);
160 	rcar_gen3_set_host_mode(ch, 0);
161 	rcar_gen3_enable_vbus_ctrl(ch, 0);
162 
163 	ch->extcon_host = false;
164 	schedule_work(&ch->work);
165 }
166 
167 static void rcar_gen3_init_for_b_host(struct rcar_gen3_chan *ch)
168 {
169 	void __iomem *usb2_base = ch->base;
170 	u32 val;
171 
172 	val = readl(usb2_base + USB2_LINECTRL1);
173 	writel(val | USB2_LINECTRL1_OPMODE_NODRV, usb2_base + USB2_LINECTRL1);
174 
175 	rcar_gen3_set_linectrl(ch, 1, 1);
176 	rcar_gen3_set_host_mode(ch, 1);
177 	rcar_gen3_enable_vbus_ctrl(ch, 0);
178 
179 	val = readl(usb2_base + USB2_LINECTRL1);
180 	writel(val & ~USB2_LINECTRL1_OPMODE_NODRV, usb2_base + USB2_LINECTRL1);
181 }
182 
183 static void rcar_gen3_init_for_a_peri(struct rcar_gen3_chan *ch)
184 {
185 	rcar_gen3_set_linectrl(ch, 0, 1);
186 	rcar_gen3_set_host_mode(ch, 0);
187 	rcar_gen3_enable_vbus_ctrl(ch, 1);
188 }
189 
190 static void rcar_gen3_init_from_a_peri_to_a_host(struct rcar_gen3_chan *ch)
191 {
192 	void __iomem *usb2_base = ch->base;
193 	u32 val;
194 
195 	val = readl(usb2_base + USB2_OBINTEN);
196 	writel(val & ~USB2_OBINT_BITS, usb2_base + USB2_OBINTEN);
197 
198 	rcar_gen3_enable_vbus_ctrl(ch, 0);
199 	rcar_gen3_init_for_host(ch);
200 
201 	writel(val | USB2_OBINT_BITS, usb2_base + USB2_OBINTEN);
202 }
203 
204 static bool rcar_gen3_check_id(struct rcar_gen3_chan *ch)
205 {
206 	return !!(readl(ch->base + USB2_ADPCTRL) & USB2_ADPCTRL_IDDIG);
207 }
208 
209 static void rcar_gen3_device_recognition(struct rcar_gen3_chan *ch)
210 {
211 	if (!rcar_gen3_check_id(ch))
212 		rcar_gen3_init_for_host(ch);
213 	else
214 		rcar_gen3_init_for_peri(ch);
215 }
216 
217 static bool rcar_gen3_is_host(struct rcar_gen3_chan *ch)
218 {
219 	return !(readl(ch->base + USB2_COMMCTRL) & USB2_COMMCTRL_OTG_PERI);
220 }
221 
222 static enum phy_mode rcar_gen3_get_phy_mode(struct rcar_gen3_chan *ch)
223 {
224 	if (rcar_gen3_is_host(ch))
225 		return PHY_MODE_USB_HOST;
226 
227 	return PHY_MODE_USB_DEVICE;
228 }
229 
230 static ssize_t role_store(struct device *dev, struct device_attribute *attr,
231 			  const char *buf, size_t count)
232 {
233 	struct rcar_gen3_chan *ch = dev_get_drvdata(dev);
234 	bool is_b_device;
235 	enum phy_mode cur_mode, new_mode;
236 
237 	if (!ch->has_otg_pins || !ch->phy->init_count)
238 		return -EIO;
239 
240 	if (!strncmp(buf, "host", strlen("host")))
241 		new_mode = PHY_MODE_USB_HOST;
242 	else if (!strncmp(buf, "peripheral", strlen("peripheral")))
243 		new_mode = PHY_MODE_USB_DEVICE;
244 	else
245 		return -EINVAL;
246 
247 	/* is_b_device: true is B-Device. false is A-Device. */
248 	is_b_device = rcar_gen3_check_id(ch);
249 	cur_mode = rcar_gen3_get_phy_mode(ch);
250 
251 	/* If current and new mode is the same, this returns the error */
252 	if (cur_mode == new_mode)
253 		return -EINVAL;
254 
255 	if (new_mode == PHY_MODE_USB_HOST) { /* And is_host must be false */
256 		if (!is_b_device)	/* A-Peripheral */
257 			rcar_gen3_init_from_a_peri_to_a_host(ch);
258 		else			/* B-Peripheral */
259 			rcar_gen3_init_for_b_host(ch);
260 	} else {			/* And is_host must be true */
261 		if (!is_b_device)	/* A-Host */
262 			rcar_gen3_init_for_a_peri(ch);
263 		else			/* B-Host */
264 			rcar_gen3_init_for_peri(ch);
265 	}
266 
267 	return count;
268 }
269 
270 static ssize_t role_show(struct device *dev, struct device_attribute *attr,
271 			 char *buf)
272 {
273 	struct rcar_gen3_chan *ch = dev_get_drvdata(dev);
274 
275 	if (!ch->has_otg_pins || !ch->phy->init_count)
276 		return -EIO;
277 
278 	return sprintf(buf, "%s\n", rcar_gen3_is_host(ch) ? "host" :
279 							    "peripheral");
280 }
281 static DEVICE_ATTR_RW(role);
282 
283 static void rcar_gen3_init_otg(struct rcar_gen3_chan *ch)
284 {
285 	void __iomem *usb2_base = ch->base;
286 	u32 val;
287 
288 	val = readl(usb2_base + USB2_VBCTRL);
289 	writel(val | USB2_VBCTRL_DRVVBUSSEL, usb2_base + USB2_VBCTRL);
290 	writel(USB2_OBINT_BITS, usb2_base + USB2_OBINTSTA);
291 	val = readl(usb2_base + USB2_OBINTEN);
292 	writel(val | USB2_OBINT_BITS, usb2_base + USB2_OBINTEN);
293 	val = readl(usb2_base + USB2_ADPCTRL);
294 	writel(val | USB2_ADPCTRL_IDPULLUP, usb2_base + USB2_ADPCTRL);
295 	val = readl(usb2_base + USB2_LINECTRL1);
296 	rcar_gen3_set_linectrl(ch, 0, 0);
297 	writel(val | USB2_LINECTRL1_DPRPD_EN | USB2_LINECTRL1_DMRPD_EN,
298 	       usb2_base + USB2_LINECTRL1);
299 
300 	rcar_gen3_device_recognition(ch);
301 }
302 
303 static int rcar_gen3_phy_usb2_init(struct phy *p)
304 {
305 	struct rcar_gen3_chan *channel = phy_get_drvdata(p);
306 	void __iomem *usb2_base = channel->base;
307 
308 	/* Initialize USB2 part */
309 	writel(USB2_INT_ENABLE_INIT, usb2_base + USB2_INT_ENABLE);
310 	writel(USB2_SPD_RSM_TIMSET_INIT, usb2_base + USB2_SPD_RSM_TIMSET);
311 	writel(USB2_OC_TIMSET_INIT, usb2_base + USB2_OC_TIMSET);
312 
313 	/* Initialize otg part */
314 	if (channel->has_otg_pins)
315 		rcar_gen3_init_otg(channel);
316 
317 	return 0;
318 }
319 
320 static int rcar_gen3_phy_usb2_exit(struct phy *p)
321 {
322 	struct rcar_gen3_chan *channel = phy_get_drvdata(p);
323 
324 	writel(0, channel->base + USB2_INT_ENABLE);
325 
326 	return 0;
327 }
328 
329 static int rcar_gen3_phy_usb2_power_on(struct phy *p)
330 {
331 	struct rcar_gen3_chan *channel = phy_get_drvdata(p);
332 	void __iomem *usb2_base = channel->base;
333 	u32 val;
334 	int ret;
335 
336 	if (channel->vbus) {
337 		ret = regulator_enable(channel->vbus);
338 		if (ret)
339 			return ret;
340 	}
341 
342 	val = readl(usb2_base + USB2_USBCTR);
343 	val |= USB2_USBCTR_PLL_RST;
344 	writel(val, usb2_base + USB2_USBCTR);
345 	val &= ~USB2_USBCTR_PLL_RST;
346 	writel(val, usb2_base + USB2_USBCTR);
347 
348 	return 0;
349 }
350 
351 static int rcar_gen3_phy_usb2_power_off(struct phy *p)
352 {
353 	struct rcar_gen3_chan *channel = phy_get_drvdata(p);
354 	int ret = 0;
355 
356 	if (channel->vbus)
357 		ret = regulator_disable(channel->vbus);
358 
359 	return ret;
360 }
361 
362 static const struct phy_ops rcar_gen3_phy_usb2_ops = {
363 	.init		= rcar_gen3_phy_usb2_init,
364 	.exit		= rcar_gen3_phy_usb2_exit,
365 	.power_on	= rcar_gen3_phy_usb2_power_on,
366 	.power_off	= rcar_gen3_phy_usb2_power_off,
367 	.owner		= THIS_MODULE,
368 };
369 
370 static irqreturn_t rcar_gen3_phy_usb2_irq(int irq, void *_ch)
371 {
372 	struct rcar_gen3_chan *ch = _ch;
373 	void __iomem *usb2_base = ch->base;
374 	u32 status = readl(usb2_base + USB2_OBINTSTA);
375 	irqreturn_t ret = IRQ_NONE;
376 
377 	if (status & USB2_OBINT_BITS) {
378 		dev_vdbg(&ch->phy->dev, "%s: %08x\n", __func__, status);
379 		writel(USB2_OBINT_BITS, usb2_base + USB2_OBINTSTA);
380 		rcar_gen3_device_recognition(ch);
381 		ret = IRQ_HANDLED;
382 	}
383 
384 	return ret;
385 }
386 
387 static const struct of_device_id rcar_gen3_phy_usb2_match_table[] = {
388 	{
389 		.compatible = "renesas,usb2-phy-r8a7795",
390 		.data = (void *)RCAR_GEN3_PHY_HAS_DEDICATED_PINS,
391 	},
392 	{
393 		.compatible = "renesas,usb2-phy-r8a7796",
394 		.data = (void *)RCAR_GEN3_PHY_HAS_DEDICATED_PINS,
395 	},
396 	{
397 		.compatible = "renesas,usb2-phy-r8a77965",
398 		.data = (void *)RCAR_GEN3_PHY_HAS_DEDICATED_PINS,
399 	},
400 	{
401 		.compatible = "renesas,rcar-gen3-usb2-phy",
402 	},
403 	{ }
404 };
405 MODULE_DEVICE_TABLE(of, rcar_gen3_phy_usb2_match_table);
406 
407 static const unsigned int rcar_gen3_phy_cable[] = {
408 	EXTCON_USB,
409 	EXTCON_USB_HOST,
410 	EXTCON_NONE,
411 };
412 
413 static int rcar_gen3_phy_usb2_probe(struct platform_device *pdev)
414 {
415 	struct device *dev = &pdev->dev;
416 	struct rcar_gen3_chan *channel;
417 	struct phy_provider *provider;
418 	struct resource *res;
419 	int irq, ret = 0;
420 
421 	if (!dev->of_node) {
422 		dev_err(dev, "This driver needs device tree\n");
423 		return -EINVAL;
424 	}
425 
426 	channel = devm_kzalloc(dev, sizeof(*channel), GFP_KERNEL);
427 	if (!channel)
428 		return -ENOMEM;
429 
430 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
431 	channel->base = devm_ioremap_resource(dev, res);
432 	if (IS_ERR(channel->base))
433 		return PTR_ERR(channel->base);
434 
435 	/* call request_irq for OTG */
436 	irq = platform_get_irq(pdev, 0);
437 	if (irq >= 0) {
438 		INIT_WORK(&channel->work, rcar_gen3_phy_usb2_work);
439 		irq = devm_request_irq(dev, irq, rcar_gen3_phy_usb2_irq,
440 				       IRQF_SHARED, dev_name(dev), channel);
441 		if (irq < 0)
442 			dev_err(dev, "No irq handler (%d)\n", irq);
443 	}
444 
445 	if (of_usb_get_dr_mode_by_phy(dev->of_node, 0) == USB_DR_MODE_OTG) {
446 		int ret;
447 
448 		channel->has_otg_pins = (uintptr_t)of_device_get_match_data(dev);
449 		channel->extcon = devm_extcon_dev_allocate(dev,
450 							rcar_gen3_phy_cable);
451 		if (IS_ERR(channel->extcon))
452 			return PTR_ERR(channel->extcon);
453 
454 		ret = devm_extcon_dev_register(dev, channel->extcon);
455 		if (ret < 0) {
456 			dev_err(dev, "Failed to register extcon\n");
457 			return ret;
458 		}
459 	}
460 
461 	/*
462 	 * devm_phy_create() will call pm_runtime_enable(&phy->dev);
463 	 * And then, phy-core will manage runtime pm for this device.
464 	 */
465 	pm_runtime_enable(dev);
466 	channel->phy = devm_phy_create(dev, NULL, &rcar_gen3_phy_usb2_ops);
467 	if (IS_ERR(channel->phy)) {
468 		dev_err(dev, "Failed to create USB2 PHY\n");
469 		ret = PTR_ERR(channel->phy);
470 		goto error;
471 	}
472 
473 	channel->vbus = devm_regulator_get_optional(dev, "vbus");
474 	if (IS_ERR(channel->vbus)) {
475 		if (PTR_ERR(channel->vbus) == -EPROBE_DEFER) {
476 			ret = PTR_ERR(channel->vbus);
477 			goto error;
478 		}
479 		channel->vbus = NULL;
480 	}
481 
482 	platform_set_drvdata(pdev, channel);
483 	phy_set_drvdata(channel->phy, channel);
484 
485 	provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
486 	if (IS_ERR(provider)) {
487 		dev_err(dev, "Failed to register PHY provider\n");
488 		ret = PTR_ERR(provider);
489 		goto error;
490 	} else if (channel->has_otg_pins) {
491 		int ret;
492 
493 		ret = device_create_file(dev, &dev_attr_role);
494 		if (ret < 0)
495 			goto error;
496 	}
497 
498 	return 0;
499 
500 error:
501 	pm_runtime_disable(dev);
502 
503 	return ret;
504 }
505 
506 static int rcar_gen3_phy_usb2_remove(struct platform_device *pdev)
507 {
508 	struct rcar_gen3_chan *channel = platform_get_drvdata(pdev);
509 
510 	if (channel->has_otg_pins)
511 		device_remove_file(&pdev->dev, &dev_attr_role);
512 
513 	pm_runtime_disable(&pdev->dev);
514 
515 	return 0;
516 };
517 
518 static struct platform_driver rcar_gen3_phy_usb2_driver = {
519 	.driver = {
520 		.name		= "phy_rcar_gen3_usb2",
521 		.of_match_table	= rcar_gen3_phy_usb2_match_table,
522 	},
523 	.probe	= rcar_gen3_phy_usb2_probe,
524 	.remove = rcar_gen3_phy_usb2_remove,
525 };
526 module_platform_driver(rcar_gen3_phy_usb2_driver);
527 
528 MODULE_LICENSE("GPL v2");
529 MODULE_DESCRIPTION("Renesas R-Car Gen3 USB 2.0 PHY");
530 MODULE_AUTHOR("Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>");
531