xref: /linux/drivers/usb/chipidea/core.c (revision 8f668fbbd571bbd5187a9a0eae150b768fc388ac)
1 /*
2  * core.c - ChipIdea USB IP core family device controller
3  *
4  * Copyright (C) 2008 Chipidea - MIPS Technologies, Inc. All rights reserved.
5  *
6  * Author: David Lopo
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 /*
14  * Description: ChipIdea USB IP core family device controller
15  *
16  * This driver is composed of several blocks:
17  * - HW:     hardware interface
18  * - DBG:    debug facilities (optional)
19  * - UTIL:   utilities
20  * - ISR:    interrupts handling
21  * - ENDPT:  endpoint operations (Gadget API)
22  * - GADGET: gadget operations (Gadget API)
23  * - BUS:    bus glue code, bus abstraction layer
24  *
25  * Compile Options
26  * - CONFIG_USB_GADGET_DEBUG_FILES: enable debug facilities
27  * - STALL_IN:  non-empty bulk-in pipes cannot be halted
28  *              if defined mass storage compliance succeeds but with warnings
29  *              => case 4: Hi >  Dn
30  *              => case 5: Hi >  Di
31  *              => case 8: Hi <> Do
32  *              if undefined usbtest 13 fails
33  * - TRACE:     enable function tracing (depends on DEBUG)
34  *
35  * Main Features
36  * - Chapter 9 & Mass Storage Compliance with Gadget File Storage
37  * - Chapter 9 Compliance with Gadget Zero (STALL_IN undefined)
38  * - Normal & LPM support
39  *
40  * USBTEST Report
41  * - OK: 0-12, 13 (STALL_IN defined) & 14
42  * - Not Supported: 15 & 16 (ISO)
43  *
44  * TODO List
45  * - OTG
46  * - Interrupt Traffic
47  * - GET_STATUS(device) - always reports 0
48  * - Gadget API (majority of optional features)
49  * - Suspend & Remote Wakeup
50  */
51 #include <linux/delay.h>
52 #include <linux/device.h>
53 #include <linux/dma-mapping.h>
54 #include <linux/platform_device.h>
55 #include <linux/module.h>
56 #include <linux/idr.h>
57 #include <linux/interrupt.h>
58 #include <linux/io.h>
59 #include <linux/kernel.h>
60 #include <linux/slab.h>
61 #include <linux/pm_runtime.h>
62 #include <linux/usb/ch9.h>
63 #include <linux/usb/gadget.h>
64 #include <linux/usb/otg.h>
65 #include <linux/usb/chipidea.h>
66 #include <linux/usb/of.h>
67 #include <linux/phy.h>
68 #include <linux/regulator/consumer.h>
69 
70 #include "ci.h"
71 #include "udc.h"
72 #include "bits.h"
73 #include "host.h"
74 #include "debug.h"
75 #include "otg.h"
76 
77 /* Controller register map */
78 static uintptr_t ci_regs_nolpm[] = {
79 	[CAP_CAPLENGTH]		= 0x000UL,
80 	[CAP_HCCPARAMS]		= 0x008UL,
81 	[CAP_DCCPARAMS]		= 0x024UL,
82 	[CAP_TESTMODE]		= 0x038UL,
83 	[OP_USBCMD]		= 0x000UL,
84 	[OP_USBSTS]		= 0x004UL,
85 	[OP_USBINTR]		= 0x008UL,
86 	[OP_DEVICEADDR]		= 0x014UL,
87 	[OP_ENDPTLISTADDR]	= 0x018UL,
88 	[OP_PORTSC]		= 0x044UL,
89 	[OP_DEVLC]		= 0x084UL,
90 	[OP_OTGSC]		= 0x064UL,
91 	[OP_USBMODE]		= 0x068UL,
92 	[OP_ENDPTSETUPSTAT]	= 0x06CUL,
93 	[OP_ENDPTPRIME]		= 0x070UL,
94 	[OP_ENDPTFLUSH]		= 0x074UL,
95 	[OP_ENDPTSTAT]		= 0x078UL,
96 	[OP_ENDPTCOMPLETE]	= 0x07CUL,
97 	[OP_ENDPTCTRL]		= 0x080UL,
98 };
99 
100 static uintptr_t ci_regs_lpm[] = {
101 	[CAP_CAPLENGTH]		= 0x000UL,
102 	[CAP_HCCPARAMS]		= 0x008UL,
103 	[CAP_DCCPARAMS]		= 0x024UL,
104 	[CAP_TESTMODE]		= 0x0FCUL,
105 	[OP_USBCMD]		= 0x000UL,
106 	[OP_USBSTS]		= 0x004UL,
107 	[OP_USBINTR]		= 0x008UL,
108 	[OP_DEVICEADDR]		= 0x014UL,
109 	[OP_ENDPTLISTADDR]	= 0x018UL,
110 	[OP_PORTSC]		= 0x044UL,
111 	[OP_DEVLC]		= 0x084UL,
112 	[OP_OTGSC]		= 0x0C4UL,
113 	[OP_USBMODE]		= 0x0C8UL,
114 	[OP_ENDPTSETUPSTAT]	= 0x0D8UL,
115 	[OP_ENDPTPRIME]		= 0x0DCUL,
116 	[OP_ENDPTFLUSH]		= 0x0E0UL,
117 	[OP_ENDPTSTAT]		= 0x0E4UL,
118 	[OP_ENDPTCOMPLETE]	= 0x0E8UL,
119 	[OP_ENDPTCTRL]		= 0x0ECUL,
120 };
121 
122 static int hw_alloc_regmap(struct ci_hdrc *ci, bool is_lpm)
123 {
124 	int i;
125 
126 	kfree(ci->hw_bank.regmap);
127 
128 	ci->hw_bank.regmap = kzalloc((OP_LAST + 1) * sizeof(void *),
129 				     GFP_KERNEL);
130 	if (!ci->hw_bank.regmap)
131 		return -ENOMEM;
132 
133 	for (i = 0; i < OP_ENDPTCTRL; i++)
134 		ci->hw_bank.regmap[i] =
135 			(i <= CAP_LAST ? ci->hw_bank.cap : ci->hw_bank.op) +
136 			(is_lpm ? ci_regs_lpm[i] : ci_regs_nolpm[i]);
137 
138 	for (; i <= OP_LAST; i++)
139 		ci->hw_bank.regmap[i] = ci->hw_bank.op +
140 			4 * (i - OP_ENDPTCTRL) +
141 			(is_lpm
142 			 ? ci_regs_lpm[OP_ENDPTCTRL]
143 			 : ci_regs_nolpm[OP_ENDPTCTRL]);
144 
145 	return 0;
146 }
147 
148 /**
149  * hw_port_test_set: writes port test mode (execute without interruption)
150  * @mode: new value
151  *
152  * This function returns an error code
153  */
154 int hw_port_test_set(struct ci_hdrc *ci, u8 mode)
155 {
156 	const u8 TEST_MODE_MAX = 7;
157 
158 	if (mode > TEST_MODE_MAX)
159 		return -EINVAL;
160 
161 	hw_write(ci, OP_PORTSC, PORTSC_PTC, mode << __ffs(PORTSC_PTC));
162 	return 0;
163 }
164 
165 /**
166  * hw_port_test_get: reads port test mode value
167  *
168  * This function returns port test mode value
169  */
170 u8 hw_port_test_get(struct ci_hdrc *ci)
171 {
172 	return hw_read(ci, OP_PORTSC, PORTSC_PTC) >> __ffs(PORTSC_PTC);
173 }
174 
175 /* The PHY enters/leaves low power mode */
176 static void ci_hdrc_enter_lpm(struct ci_hdrc *ci, bool enable)
177 {
178 	enum ci_hw_regs reg = ci->hw_bank.lpm ? OP_DEVLC : OP_PORTSC;
179 	bool lpm = !!(hw_read(ci, reg, PORTSC_PHCD(ci->hw_bank.lpm)));
180 
181 	if (enable && !lpm) {
182 		hw_write(ci, reg, PORTSC_PHCD(ci->hw_bank.lpm),
183 				PORTSC_PHCD(ci->hw_bank.lpm));
184 	} else  if (!enable && lpm) {
185 		hw_write(ci, reg, PORTSC_PHCD(ci->hw_bank.lpm),
186 				0);
187 		/*
188 		 * The controller needs at least 1ms to reflect
189 		 * PHY's status, the PHY also needs some time (less
190 		 * than 1ms) to leave low power mode.
191 		 */
192 		usleep_range(1500, 2000);
193 	}
194 }
195 
196 static int hw_device_init(struct ci_hdrc *ci, void __iomem *base)
197 {
198 	u32 reg;
199 
200 	/* bank is a module variable */
201 	ci->hw_bank.abs = base;
202 
203 	ci->hw_bank.cap = ci->hw_bank.abs;
204 	ci->hw_bank.cap += ci->platdata->capoffset;
205 	ci->hw_bank.op = ci->hw_bank.cap + (ioread32(ci->hw_bank.cap) & 0xff);
206 
207 	hw_alloc_regmap(ci, false);
208 	reg = hw_read(ci, CAP_HCCPARAMS, HCCPARAMS_LEN) >>
209 		__ffs(HCCPARAMS_LEN);
210 	ci->hw_bank.lpm  = reg;
211 	if (reg)
212 		hw_alloc_regmap(ci, !!reg);
213 	ci->hw_bank.size = ci->hw_bank.op - ci->hw_bank.abs;
214 	ci->hw_bank.size += OP_LAST;
215 	ci->hw_bank.size /= sizeof(u32);
216 
217 	reg = hw_read(ci, CAP_DCCPARAMS, DCCPARAMS_DEN) >>
218 		__ffs(DCCPARAMS_DEN);
219 	ci->hw_ep_max = reg * 2;   /* cache hw ENDPT_MAX */
220 
221 	if (ci->hw_ep_max > ENDPT_MAX)
222 		return -ENODEV;
223 
224 	ci_hdrc_enter_lpm(ci, false);
225 
226 	/* Disable all interrupts bits */
227 	hw_write(ci, OP_USBINTR, 0xffffffff, 0);
228 
229 	/* Clear all interrupts status bits*/
230 	hw_write(ci, OP_USBSTS, 0xffffffff, 0xffffffff);
231 
232 	dev_dbg(ci->dev, "ChipIdea HDRC found, lpm: %d; cap: %p op: %p\n",
233 		ci->hw_bank.lpm, ci->hw_bank.cap, ci->hw_bank.op);
234 
235 	/* setup lock mode ? */
236 
237 	/* ENDPTSETUPSTAT is '0' by default */
238 
239 	/* HCSPARAMS.bf.ppc SHOULD BE zero for device */
240 
241 	return 0;
242 }
243 
244 static void hw_phymode_configure(struct ci_hdrc *ci)
245 {
246 	u32 portsc, lpm, sts;
247 
248 	switch (ci->platdata->phy_mode) {
249 	case USBPHY_INTERFACE_MODE_UTMI:
250 		portsc = PORTSC_PTS(PTS_UTMI);
251 		lpm = DEVLC_PTS(PTS_UTMI);
252 		break;
253 	case USBPHY_INTERFACE_MODE_UTMIW:
254 		portsc = PORTSC_PTS(PTS_UTMI) | PORTSC_PTW;
255 		lpm = DEVLC_PTS(PTS_UTMI) | DEVLC_PTW;
256 		break;
257 	case USBPHY_INTERFACE_MODE_ULPI:
258 		portsc = PORTSC_PTS(PTS_ULPI);
259 		lpm = DEVLC_PTS(PTS_ULPI);
260 		break;
261 	case USBPHY_INTERFACE_MODE_SERIAL:
262 		portsc = PORTSC_PTS(PTS_SERIAL);
263 		lpm = DEVLC_PTS(PTS_SERIAL);
264 		sts = 1;
265 		break;
266 	case USBPHY_INTERFACE_MODE_HSIC:
267 		portsc = PORTSC_PTS(PTS_HSIC);
268 		lpm = DEVLC_PTS(PTS_HSIC);
269 		break;
270 	default:
271 		return;
272 	}
273 
274 	if (ci->hw_bank.lpm) {
275 		hw_write(ci, OP_DEVLC, DEVLC_PTS(7) | DEVLC_PTW, lpm);
276 		hw_write(ci, OP_DEVLC, DEVLC_STS, sts);
277 	} else {
278 		hw_write(ci, OP_PORTSC, PORTSC_PTS(7) | PORTSC_PTW, portsc);
279 		hw_write(ci, OP_PORTSC, PORTSC_STS, sts);
280 	}
281 }
282 
283 /**
284  * hw_device_reset: resets chip (execute without interruption)
285  * @ci: the controller
286   *
287  * This function returns an error code
288  */
289 int hw_device_reset(struct ci_hdrc *ci, u32 mode)
290 {
291 	/* should flush & stop before reset */
292 	hw_write(ci, OP_ENDPTFLUSH, ~0, ~0);
293 	hw_write(ci, OP_USBCMD, USBCMD_RS, 0);
294 
295 	hw_write(ci, OP_USBCMD, USBCMD_RST, USBCMD_RST);
296 	while (hw_read(ci, OP_USBCMD, USBCMD_RST))
297 		udelay(10);		/* not RTOS friendly */
298 
299 	if (ci->platdata->notify_event)
300 		ci->platdata->notify_event(ci,
301 			CI_HDRC_CONTROLLER_RESET_EVENT);
302 
303 	if (ci->platdata->flags & CI_HDRC_DISABLE_STREAMING)
304 		hw_write(ci, OP_USBMODE, USBMODE_CI_SDIS, USBMODE_CI_SDIS);
305 
306 	/* USBMODE should be configured step by step */
307 	hw_write(ci, OP_USBMODE, USBMODE_CM, USBMODE_CM_IDLE);
308 	hw_write(ci, OP_USBMODE, USBMODE_CM, mode);
309 	/* HW >= 2.3 */
310 	hw_write(ci, OP_USBMODE, USBMODE_SLOM, USBMODE_SLOM);
311 
312 	if (hw_read(ci, OP_USBMODE, USBMODE_CM) != mode) {
313 		pr_err("cannot enter in %s mode", ci_role(ci)->name);
314 		pr_err("lpm = %i", ci->hw_bank.lpm);
315 		return -ENODEV;
316 	}
317 
318 	return 0;
319 }
320 
321 /**
322  * hw_wait_reg: wait the register value
323  *
324  * Sometimes, it needs to wait register value before going on.
325  * Eg, when switch to device mode, the vbus value should be lower
326  * than OTGSC_BSV before connects to host.
327  *
328  * @ci: the controller
329  * @reg: register index
330  * @mask: mast bit
331  * @value: the bit value to wait
332  * @timeout_ms: timeout in millisecond
333  *
334  * This function returns an error code if timeout
335  */
336 int hw_wait_reg(struct ci_hdrc *ci, enum ci_hw_regs reg, u32 mask,
337 				u32 value, unsigned int timeout_ms)
338 {
339 	unsigned long elapse = jiffies + msecs_to_jiffies(timeout_ms);
340 
341 	while (hw_read(ci, reg, mask) != value) {
342 		if (time_after(jiffies, elapse)) {
343 			dev_err(ci->dev, "timeout waiting for %08x in %d\n",
344 					mask, reg);
345 			return -ETIMEDOUT;
346 		}
347 		msleep(20);
348 	}
349 
350 	return 0;
351 }
352 
353 static irqreturn_t ci_irq(int irq, void *data)
354 {
355 	struct ci_hdrc *ci = data;
356 	irqreturn_t ret = IRQ_NONE;
357 	u32 otgsc = 0;
358 
359 	if (ci->is_otg)
360 		otgsc = hw_read(ci, OP_OTGSC, ~0);
361 
362 	/*
363 	 * Handle id change interrupt, it indicates device/host function
364 	 * switch.
365 	 */
366 	if (ci->is_otg && (otgsc & OTGSC_IDIE) && (otgsc & OTGSC_IDIS)) {
367 		ci->id_event = true;
368 		ci_clear_otg_interrupt(ci, OTGSC_IDIS);
369 		disable_irq_nosync(ci->irq);
370 		queue_work(ci->wq, &ci->work);
371 		return IRQ_HANDLED;
372 	}
373 
374 	/*
375 	 * Handle vbus change interrupt, it indicates device connection
376 	 * and disconnection events.
377 	 */
378 	if (ci->is_otg && (otgsc & OTGSC_BSVIE) && (otgsc & OTGSC_BSVIS)) {
379 		ci->b_sess_valid_event = true;
380 		ci_clear_otg_interrupt(ci, OTGSC_BSVIS);
381 		disable_irq_nosync(ci->irq);
382 		queue_work(ci->wq, &ci->work);
383 		return IRQ_HANDLED;
384 	}
385 
386 	/* Handle device/host interrupt */
387 	if (ci->role != CI_ROLE_END)
388 		ret = ci_role(ci)->irq(ci);
389 
390 	return ret;
391 }
392 
393 static int ci_get_platdata(struct device *dev,
394 		struct ci_hdrc_platform_data *platdata)
395 {
396 	if (!platdata->phy_mode)
397 		platdata->phy_mode = of_usb_get_phy_mode(dev->of_node);
398 
399 	if (!platdata->dr_mode)
400 		platdata->dr_mode = of_usb_get_dr_mode(dev->of_node);
401 
402 	if (platdata->dr_mode == USB_DR_MODE_UNKNOWN)
403 		platdata->dr_mode = USB_DR_MODE_OTG;
404 
405 	if (platdata->dr_mode != USB_DR_MODE_PERIPHERAL) {
406 		/* Get the vbus regulator */
407 		platdata->reg_vbus = devm_regulator_get(dev, "vbus");
408 		if (PTR_ERR(platdata->reg_vbus) == -EPROBE_DEFER) {
409 			return -EPROBE_DEFER;
410 		} else if (PTR_ERR(platdata->reg_vbus) == -ENODEV) {
411 			/* no vbus regualator is needed */
412 			platdata->reg_vbus = NULL;
413 		} else if (IS_ERR(platdata->reg_vbus)) {
414 			dev_err(dev, "Getting regulator error: %ld\n",
415 				PTR_ERR(platdata->reg_vbus));
416 			return PTR_ERR(platdata->reg_vbus);
417 		}
418 	}
419 
420 	return 0;
421 }
422 
423 static DEFINE_IDA(ci_ida);
424 
425 struct platform_device *ci_hdrc_add_device(struct device *dev,
426 			struct resource *res, int nres,
427 			struct ci_hdrc_platform_data *platdata)
428 {
429 	struct platform_device *pdev;
430 	int id, ret;
431 
432 	ret = ci_get_platdata(dev, platdata);
433 	if (ret)
434 		return ERR_PTR(ret);
435 
436 	id = ida_simple_get(&ci_ida, 0, 0, GFP_KERNEL);
437 	if (id < 0)
438 		return ERR_PTR(id);
439 
440 	pdev = platform_device_alloc("ci_hdrc", id);
441 	if (!pdev) {
442 		ret = -ENOMEM;
443 		goto put_id;
444 	}
445 
446 	pdev->dev.parent = dev;
447 	pdev->dev.dma_mask = dev->dma_mask;
448 	pdev->dev.dma_parms = dev->dma_parms;
449 	dma_set_coherent_mask(&pdev->dev, dev->coherent_dma_mask);
450 
451 	ret = platform_device_add_resources(pdev, res, nres);
452 	if (ret)
453 		goto err;
454 
455 	ret = platform_device_add_data(pdev, platdata, sizeof(*platdata));
456 	if (ret)
457 		goto err;
458 
459 	ret = platform_device_add(pdev);
460 	if (ret)
461 		goto err;
462 
463 	return pdev;
464 
465 err:
466 	platform_device_put(pdev);
467 put_id:
468 	ida_simple_remove(&ci_ida, id);
469 	return ERR_PTR(ret);
470 }
471 EXPORT_SYMBOL_GPL(ci_hdrc_add_device);
472 
473 void ci_hdrc_remove_device(struct platform_device *pdev)
474 {
475 	int id = pdev->id;
476 	platform_device_unregister(pdev);
477 	ida_simple_remove(&ci_ida, id);
478 }
479 EXPORT_SYMBOL_GPL(ci_hdrc_remove_device);
480 
481 static inline void ci_role_destroy(struct ci_hdrc *ci)
482 {
483 	ci_hdrc_gadget_destroy(ci);
484 	ci_hdrc_host_destroy(ci);
485 	if (ci->is_otg)
486 		ci_hdrc_otg_destroy(ci);
487 }
488 
489 static void ci_get_otg_capable(struct ci_hdrc *ci)
490 {
491 	if (ci->platdata->flags & CI_HDRC_DUAL_ROLE_NOT_OTG)
492 		ci->is_otg = false;
493 	else
494 		ci->is_otg = (hw_read(ci, CAP_DCCPARAMS,
495 				DCCPARAMS_DC | DCCPARAMS_HC)
496 					== (DCCPARAMS_DC | DCCPARAMS_HC));
497 	if (ci->is_otg) {
498 		dev_dbg(ci->dev, "It is OTG capable controller\n");
499 		ci_disable_otg_interrupt(ci, OTGSC_INT_EN_BITS);
500 		ci_clear_otg_interrupt(ci, OTGSC_INT_STATUS_BITS);
501 	}
502 }
503 
504 static int ci_usb_phy_init(struct ci_hdrc *ci)
505 {
506 	if (ci->platdata->phy) {
507 		ci->transceiver = ci->platdata->phy;
508 		return usb_phy_init(ci->transceiver);
509 	} else {
510 		ci->global_phy = true;
511 		ci->transceiver = usb_get_phy(USB_PHY_TYPE_USB2);
512 		if (IS_ERR(ci->transceiver))
513 			ci->transceiver = NULL;
514 
515 		return 0;
516 	}
517 }
518 
519 static void ci_usb_phy_destroy(struct ci_hdrc *ci)
520 {
521 	if (!ci->transceiver)
522 		return;
523 
524 	otg_set_peripheral(ci->transceiver->otg, NULL);
525 	if (ci->global_phy)
526 		usb_put_phy(ci->transceiver);
527 	else
528 		usb_phy_shutdown(ci->transceiver);
529 }
530 
531 static int ci_hdrc_probe(struct platform_device *pdev)
532 {
533 	struct device	*dev = &pdev->dev;
534 	struct ci_hdrc	*ci;
535 	struct resource	*res;
536 	void __iomem	*base;
537 	int		ret;
538 	enum usb_dr_mode dr_mode;
539 
540 	if (!dev->platform_data) {
541 		dev_err(dev, "platform data missing\n");
542 		return -ENODEV;
543 	}
544 
545 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
546 	base = devm_ioremap_resource(dev, res);
547 	if (IS_ERR(base))
548 		return PTR_ERR(base);
549 
550 	ci = devm_kzalloc(dev, sizeof(*ci), GFP_KERNEL);
551 	if (!ci) {
552 		dev_err(dev, "can't allocate device\n");
553 		return -ENOMEM;
554 	}
555 
556 	ci->dev = dev;
557 	ci->platdata = dev->platform_data;
558 
559 	ret = hw_device_init(ci, base);
560 	if (ret < 0) {
561 		dev_err(dev, "can't initialize hardware\n");
562 		return -ENODEV;
563 	}
564 
565 	ret = ci_usb_phy_init(ci);
566 	if (ret) {
567 		dev_err(dev, "unable to init phy: %d\n", ret);
568 		return ret;
569 	}
570 
571 	ci->hw_bank.phys = res->start;
572 
573 	ci->irq = platform_get_irq(pdev, 0);
574 	if (ci->irq < 0) {
575 		dev_err(dev, "missing IRQ\n");
576 		ret = -ENODEV;
577 		goto destroy_phy;
578 	}
579 
580 	ci_get_otg_capable(ci);
581 
582 	hw_phymode_configure(ci);
583 
584 	dr_mode = ci->platdata->dr_mode;
585 	/* initialize role(s) before the interrupt is requested */
586 	if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_HOST) {
587 		ret = ci_hdrc_host_init(ci);
588 		if (ret)
589 			dev_info(dev, "doesn't support host\n");
590 	}
591 
592 	if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_PERIPHERAL) {
593 		ret = ci_hdrc_gadget_init(ci);
594 		if (ret)
595 			dev_info(dev, "doesn't support gadget\n");
596 		if (!ret && ci->transceiver) {
597 			ret = otg_set_peripheral(ci->transceiver->otg,
598 							&ci->gadget);
599 			/*
600 			 * If we implement all USB functions using chipidea drivers,
601 			 * it doesn't need to call above API, meanwhile, if we only
602 			 * use gadget function, calling above API is useless.
603 			 */
604 			if (ret && ret != -ENOTSUPP)
605 				goto destroy_phy;
606 		}
607 	}
608 
609 	if (!ci->roles[CI_ROLE_HOST] && !ci->roles[CI_ROLE_GADGET]) {
610 		dev_err(dev, "no supported roles\n");
611 		ret = -ENODEV;
612 		goto destroy_phy;
613 	}
614 
615 	if (ci->is_otg) {
616 		ret = ci_hdrc_otg_init(ci);
617 		if (ret) {
618 			dev_err(dev, "init otg fails, ret = %d\n", ret);
619 			goto stop;
620 		}
621 	}
622 
623 	if (ci->roles[CI_ROLE_HOST] && ci->roles[CI_ROLE_GADGET]) {
624 		if (ci->is_otg) {
625 			/*
626 			 * ID pin needs 1ms debouce time,
627 			 * we delay 2ms for safe.
628 			 */
629 			mdelay(2);
630 			ci->role = ci_otg_role(ci);
631 			ci_enable_otg_interrupt(ci, OTGSC_IDIE);
632 		} else {
633 			/*
634 			 * If the controller is not OTG capable, but support
635 			 * role switch, the defalt role is gadget, and the
636 			 * user can switch it through debugfs.
637 			 */
638 			ci->role = CI_ROLE_GADGET;
639 		}
640 	} else {
641 		ci->role = ci->roles[CI_ROLE_HOST]
642 			? CI_ROLE_HOST
643 			: CI_ROLE_GADGET;
644 	}
645 
646 	/* only update vbus status for peripheral */
647 	if (ci->role == CI_ROLE_GADGET)
648 		ci_handle_vbus_change(ci);
649 
650 	ret = ci_role_start(ci, ci->role);
651 	if (ret) {
652 		dev_err(dev, "can't start %s role\n", ci_role(ci)->name);
653 		goto stop;
654 	}
655 
656 	platform_set_drvdata(pdev, ci);
657 	ret = request_irq(ci->irq, ci_irq, IRQF_SHARED, ci->platdata->name,
658 			  ci);
659 	if (ret)
660 		goto stop;
661 
662 	ret = dbg_create_files(ci);
663 	if (!ret)
664 		return 0;
665 
666 	free_irq(ci->irq, ci);
667 stop:
668 	ci_role_destroy(ci);
669 destroy_phy:
670 	ci_usb_phy_destroy(ci);
671 
672 	return ret;
673 }
674 
675 static int ci_hdrc_remove(struct platform_device *pdev)
676 {
677 	struct ci_hdrc *ci = platform_get_drvdata(pdev);
678 
679 	dbg_remove_files(ci);
680 	free_irq(ci->irq, ci);
681 	ci_role_destroy(ci);
682 	ci_hdrc_enter_lpm(ci, true);
683 	ci_usb_phy_destroy(ci);
684 	kfree(ci->hw_bank.regmap);
685 
686 	return 0;
687 }
688 
689 static struct platform_driver ci_hdrc_driver = {
690 	.probe	= ci_hdrc_probe,
691 	.remove	= ci_hdrc_remove,
692 	.driver	= {
693 		.name	= "ci_hdrc",
694 	},
695 };
696 
697 module_platform_driver(ci_hdrc_driver);
698 
699 MODULE_ALIAS("platform:ci_hdrc");
700 MODULE_LICENSE("GPL v2");
701 MODULE_AUTHOR("David Lopo <dlopo@chipidea.mips.com>");
702 MODULE_DESCRIPTION("ChipIdea HDRC Driver");
703