xref: /linux/drivers/usb/phy/phy-fsl-usb.c (revision 2ba9268dd603d23e17643437b2246acb6844953b)
1 /*
2  * Copyright (C) 2007,2008 Freescale semiconductor, Inc.
3  *
4  * Author: Li Yang <LeoLi@freescale.com>
5  *         Jerry Huang <Chang-Ming.Huang@freescale.com>
6  *
7  * Initialization based on code from Shlomi Gridish.
8  *
9  * This program is free software; you can redistribute  it and/or modify it
10  * under  the terms of  the GNU General  Public License as published by the
11  * Free Software Foundation;  either version 2 of the  License, or (at your
12  * option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the  GNU General Public License along
20  * with this program; if not, write  to the Free Software Foundation, Inc.,
21  * 675 Mass Ave, Cambridge, MA 02139, USA.
22  */
23 
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/delay.h>
27 #include <linux/slab.h>
28 #include <linux/proc_fs.h>
29 #include <linux/errno.h>
30 #include <linux/interrupt.h>
31 #include <linux/io.h>
32 #include <linux/timer.h>
33 #include <linux/usb.h>
34 #include <linux/device.h>
35 #include <linux/usb/ch9.h>
36 #include <linux/usb/gadget.h>
37 #include <linux/workqueue.h>
38 #include <linux/time.h>
39 #include <linux/fsl_devices.h>
40 #include <linux/platform_device.h>
41 #include <linux/uaccess.h>
42 
43 #include <asm/unaligned.h>
44 
45 #include "phy-fsl-usb.h"
46 
47 #define DRIVER_VERSION "Rev. 1.55"
48 #define DRIVER_AUTHOR "Jerry Huang/Li Yang"
49 #define DRIVER_DESC "Freescale USB OTG Transceiver Driver"
50 #define DRIVER_INFO DRIVER_DESC " " DRIVER_VERSION
51 
52 static const char driver_name[] = "fsl-usb2-otg";
53 
54 const pm_message_t otg_suspend_state = {
55 	.event = 1,
56 };
57 
58 #define HA_DATA_PULSE
59 
60 static struct usb_dr_mmap *usb_dr_regs;
61 static struct fsl_otg *fsl_otg_dev;
62 static int srp_wait_done;
63 
64 /* FSM timers */
65 struct fsl_otg_timer *a_wait_vrise_tmr, *a_wait_bcon_tmr, *a_aidl_bdis_tmr,
66 	*b_ase0_brst_tmr, *b_se0_srp_tmr;
67 
68 /* Driver specific timers */
69 struct fsl_otg_timer *b_data_pulse_tmr, *b_vbus_pulse_tmr, *b_srp_fail_tmr,
70 	*b_srp_wait_tmr, *a_wait_enum_tmr;
71 
72 static struct list_head active_timers;
73 
74 static struct fsl_otg_config fsl_otg_initdata = {
75 	.otg_port = 1,
76 };
77 
78 #ifdef CONFIG_PPC32
79 static u32 _fsl_readl_be(const unsigned __iomem *p)
80 {
81 	return in_be32(p);
82 }
83 
84 static u32 _fsl_readl_le(const unsigned __iomem *p)
85 {
86 	return in_le32(p);
87 }
88 
89 static void _fsl_writel_be(u32 v, unsigned __iomem *p)
90 {
91 	out_be32(p, v);
92 }
93 
94 static void _fsl_writel_le(u32 v, unsigned __iomem *p)
95 {
96 	out_le32(p, v);
97 }
98 
99 static u32 (*_fsl_readl)(const unsigned __iomem *p);
100 static void (*_fsl_writel)(u32 v, unsigned __iomem *p);
101 
102 #define fsl_readl(p)		(*_fsl_readl)((p))
103 #define fsl_writel(v, p)	(*_fsl_writel)((v), (p))
104 
105 #else
106 #define fsl_readl(addr)		readl(addr)
107 #define fsl_writel(val, addr)	writel(val, addr)
108 #endif /* CONFIG_PPC32 */
109 
110 int write_ulpi(u8 addr, u8 data)
111 {
112 	u32 temp;
113 
114 	temp = 0x60000000 | (addr << 16) | data;
115 	fsl_writel(temp, &usb_dr_regs->ulpiview);
116 	return 0;
117 }
118 
119 /* -------------------------------------------------------------*/
120 /* Operations that will be called from OTG Finite State Machine */
121 
122 /* Charge vbus for vbus pulsing in SRP */
123 void fsl_otg_chrg_vbus(struct otg_fsm *fsm, int on)
124 {
125 	u32 tmp;
126 
127 	tmp = fsl_readl(&usb_dr_regs->otgsc) & ~OTGSC_INTSTS_MASK;
128 
129 	if (on)
130 		/* stop discharging, start charging */
131 		tmp = (tmp & ~OTGSC_CTRL_VBUS_DISCHARGE) |
132 			OTGSC_CTRL_VBUS_CHARGE;
133 	else
134 		/* stop charging */
135 		tmp &= ~OTGSC_CTRL_VBUS_CHARGE;
136 
137 	fsl_writel(tmp, &usb_dr_regs->otgsc);
138 }
139 
140 /* Discharge vbus through a resistor to ground */
141 void fsl_otg_dischrg_vbus(int on)
142 {
143 	u32 tmp;
144 
145 	tmp = fsl_readl(&usb_dr_regs->otgsc) & ~OTGSC_INTSTS_MASK;
146 
147 	if (on)
148 		/* stop charging, start discharging */
149 		tmp = (tmp & ~OTGSC_CTRL_VBUS_CHARGE) |
150 			OTGSC_CTRL_VBUS_DISCHARGE;
151 	else
152 		/* stop discharging */
153 		tmp &= ~OTGSC_CTRL_VBUS_DISCHARGE;
154 
155 	fsl_writel(tmp, &usb_dr_regs->otgsc);
156 }
157 
158 /* A-device driver vbus, controlled through PP bit in PORTSC */
159 void fsl_otg_drv_vbus(struct otg_fsm *fsm, int on)
160 {
161 	u32 tmp;
162 
163 	if (on) {
164 		tmp = fsl_readl(&usb_dr_regs->portsc) & ~PORTSC_W1C_BITS;
165 		fsl_writel(tmp | PORTSC_PORT_POWER, &usb_dr_regs->portsc);
166 	} else {
167 		tmp = fsl_readl(&usb_dr_regs->portsc) &
168 		      ~PORTSC_W1C_BITS & ~PORTSC_PORT_POWER;
169 		fsl_writel(tmp, &usb_dr_regs->portsc);
170 	}
171 }
172 
173 /*
174  * Pull-up D+, signalling connect by periperal. Also used in
175  * data-line pulsing in SRP
176  */
177 void fsl_otg_loc_conn(struct otg_fsm *fsm, int on)
178 {
179 	u32 tmp;
180 
181 	tmp = fsl_readl(&usb_dr_regs->otgsc) & ~OTGSC_INTSTS_MASK;
182 
183 	if (on)
184 		tmp |= OTGSC_CTRL_DATA_PULSING;
185 	else
186 		tmp &= ~OTGSC_CTRL_DATA_PULSING;
187 
188 	fsl_writel(tmp, &usb_dr_regs->otgsc);
189 }
190 
191 /*
192  * Generate SOF by host.  This is controlled through suspend/resume the
193  * port.  In host mode, controller will automatically send SOF.
194  * Suspend will block the data on the port.
195  */
196 void fsl_otg_loc_sof(struct otg_fsm *fsm, int on)
197 {
198 	u32 tmp;
199 
200 	tmp = fsl_readl(&fsl_otg_dev->dr_mem_map->portsc) & ~PORTSC_W1C_BITS;
201 	if (on)
202 		tmp |= PORTSC_PORT_FORCE_RESUME;
203 	else
204 		tmp |= PORTSC_PORT_SUSPEND;
205 
206 	fsl_writel(tmp, &fsl_otg_dev->dr_mem_map->portsc);
207 
208 }
209 
210 /* Start SRP pulsing by data-line pulsing, followed with v-bus pulsing. */
211 void fsl_otg_start_pulse(struct otg_fsm *fsm)
212 {
213 	u32 tmp;
214 
215 	srp_wait_done = 0;
216 #ifdef HA_DATA_PULSE
217 	tmp = fsl_readl(&usb_dr_regs->otgsc) & ~OTGSC_INTSTS_MASK;
218 	tmp |= OTGSC_HA_DATA_PULSE;
219 	fsl_writel(tmp, &usb_dr_regs->otgsc);
220 #else
221 	fsl_otg_loc_conn(1);
222 #endif
223 
224 	fsl_otg_add_timer(fsm, b_data_pulse_tmr);
225 }
226 
227 void b_data_pulse_end(unsigned long foo)
228 {
229 #ifdef HA_DATA_PULSE
230 #else
231 	fsl_otg_loc_conn(0);
232 #endif
233 
234 	/* Do VBUS pulse after data pulse */
235 	fsl_otg_pulse_vbus();
236 }
237 
238 void fsl_otg_pulse_vbus(void)
239 {
240 	srp_wait_done = 0;
241 	fsl_otg_chrg_vbus(&fsl_otg_dev->fsm, 1);
242 	/* start the timer to end vbus charge */
243 	fsl_otg_add_timer(&fsl_otg_dev->fsm, b_vbus_pulse_tmr);
244 }
245 
246 void b_vbus_pulse_end(unsigned long foo)
247 {
248 	fsl_otg_chrg_vbus(&fsl_otg_dev->fsm, 0);
249 
250 	/*
251 	 * As USB3300 using the same a_sess_vld and b_sess_vld voltage
252 	 * we need to discharge the bus for a while to distinguish
253 	 * residual voltage of vbus pulsing and A device pull up
254 	 */
255 	fsl_otg_dischrg_vbus(1);
256 	fsl_otg_add_timer(&fsl_otg_dev->fsm, b_srp_wait_tmr);
257 }
258 
259 void b_srp_end(unsigned long foo)
260 {
261 	fsl_otg_dischrg_vbus(0);
262 	srp_wait_done = 1;
263 
264 	if ((fsl_otg_dev->phy.otg->state == OTG_STATE_B_SRP_INIT) &&
265 	    fsl_otg_dev->fsm.b_sess_vld)
266 		fsl_otg_dev->fsm.b_srp_done = 1;
267 }
268 
269 /*
270  * Workaround for a_host suspending too fast.  When a_bus_req=0,
271  * a_host will start by SRP.  It needs to set b_hnp_enable before
272  * actually suspending to start HNP
273  */
274 void a_wait_enum(unsigned long foo)
275 {
276 	VDBG("a_wait_enum timeout\n");
277 	if (!fsl_otg_dev->phy.otg->host->b_hnp_enable)
278 		fsl_otg_add_timer(&fsl_otg_dev->fsm, a_wait_enum_tmr);
279 	else
280 		otg_statemachine(&fsl_otg_dev->fsm);
281 }
282 
283 /* The timeout callback function to set time out bit */
284 void set_tmout(unsigned long indicator)
285 {
286 	*(int *)indicator = 1;
287 }
288 
289 /* Initialize timers */
290 int fsl_otg_init_timers(struct otg_fsm *fsm)
291 {
292 	/* FSM used timers */
293 	a_wait_vrise_tmr = otg_timer_initializer(&set_tmout, TA_WAIT_VRISE,
294 				(unsigned long)&fsm->a_wait_vrise_tmout);
295 	if (!a_wait_vrise_tmr)
296 		return -ENOMEM;
297 
298 	a_wait_bcon_tmr = otg_timer_initializer(&set_tmout, TA_WAIT_BCON,
299 				(unsigned long)&fsm->a_wait_bcon_tmout);
300 	if (!a_wait_bcon_tmr)
301 		return -ENOMEM;
302 
303 	a_aidl_bdis_tmr = otg_timer_initializer(&set_tmout, TA_AIDL_BDIS,
304 				(unsigned long)&fsm->a_aidl_bdis_tmout);
305 	if (!a_aidl_bdis_tmr)
306 		return -ENOMEM;
307 
308 	b_ase0_brst_tmr = otg_timer_initializer(&set_tmout, TB_ASE0_BRST,
309 				(unsigned long)&fsm->b_ase0_brst_tmout);
310 	if (!b_ase0_brst_tmr)
311 		return -ENOMEM;
312 
313 	b_se0_srp_tmr = otg_timer_initializer(&set_tmout, TB_SE0_SRP,
314 				(unsigned long)&fsm->b_se0_srp);
315 	if (!b_se0_srp_tmr)
316 		return -ENOMEM;
317 
318 	b_srp_fail_tmr = otg_timer_initializer(&set_tmout, TB_SRP_FAIL,
319 				(unsigned long)&fsm->b_srp_done);
320 	if (!b_srp_fail_tmr)
321 		return -ENOMEM;
322 
323 	a_wait_enum_tmr = otg_timer_initializer(&a_wait_enum, 10,
324 				(unsigned long)&fsm);
325 	if (!a_wait_enum_tmr)
326 		return -ENOMEM;
327 
328 	/* device driver used timers */
329 	b_srp_wait_tmr = otg_timer_initializer(&b_srp_end, TB_SRP_WAIT, 0);
330 	if (!b_srp_wait_tmr)
331 		return -ENOMEM;
332 
333 	b_data_pulse_tmr = otg_timer_initializer(&b_data_pulse_end,
334 				TB_DATA_PLS, 0);
335 	if (!b_data_pulse_tmr)
336 		return -ENOMEM;
337 
338 	b_vbus_pulse_tmr = otg_timer_initializer(&b_vbus_pulse_end,
339 				TB_VBUS_PLS, 0);
340 	if (!b_vbus_pulse_tmr)
341 		return -ENOMEM;
342 
343 	return 0;
344 }
345 
346 /* Uninitialize timers */
347 void fsl_otg_uninit_timers(void)
348 {
349 	/* FSM used timers */
350 	kfree(a_wait_vrise_tmr);
351 	kfree(a_wait_bcon_tmr);
352 	kfree(a_aidl_bdis_tmr);
353 	kfree(b_ase0_brst_tmr);
354 	kfree(b_se0_srp_tmr);
355 	kfree(b_srp_fail_tmr);
356 	kfree(a_wait_enum_tmr);
357 
358 	/* device driver used timers */
359 	kfree(b_srp_wait_tmr);
360 	kfree(b_data_pulse_tmr);
361 	kfree(b_vbus_pulse_tmr);
362 }
363 
364 static struct fsl_otg_timer *fsl_otg_get_timer(enum otg_fsm_timer t)
365 {
366 	struct fsl_otg_timer *timer;
367 
368 	/* REVISIT: use array of pointers to timers instead */
369 	switch (t) {
370 	case A_WAIT_VRISE:
371 		timer = a_wait_vrise_tmr;
372 		break;
373 	case A_WAIT_BCON:
374 		timer = a_wait_vrise_tmr;
375 		break;
376 	case A_AIDL_BDIS:
377 		timer = a_wait_vrise_tmr;
378 		break;
379 	case B_ASE0_BRST:
380 		timer = a_wait_vrise_tmr;
381 		break;
382 	case B_SE0_SRP:
383 		timer = a_wait_vrise_tmr;
384 		break;
385 	case B_SRP_FAIL:
386 		timer = a_wait_vrise_tmr;
387 		break;
388 	case A_WAIT_ENUM:
389 		timer = a_wait_vrise_tmr;
390 		break;
391 	default:
392 		timer = NULL;
393 	}
394 
395 	return timer;
396 }
397 
398 /* Add timer to timer list */
399 void fsl_otg_add_timer(struct otg_fsm *fsm, void *gtimer)
400 {
401 	struct fsl_otg_timer *timer = gtimer;
402 	struct fsl_otg_timer *tmp_timer;
403 
404 	/*
405 	 * Check if the timer is already in the active list,
406 	 * if so update timer count
407 	 */
408 	list_for_each_entry(tmp_timer, &active_timers, list)
409 	    if (tmp_timer == timer) {
410 		timer->count = timer->expires;
411 		return;
412 	}
413 	timer->count = timer->expires;
414 	list_add_tail(&timer->list, &active_timers);
415 }
416 
417 static void fsl_otg_fsm_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer t)
418 {
419 	struct fsl_otg_timer *timer;
420 
421 	timer = fsl_otg_get_timer(t);
422 	if (!timer)
423 		return;
424 
425 	fsl_otg_add_timer(fsm, timer);
426 }
427 
428 /* Remove timer from the timer list; clear timeout status */
429 void fsl_otg_del_timer(struct otg_fsm *fsm, void *gtimer)
430 {
431 	struct fsl_otg_timer *timer = gtimer;
432 	struct fsl_otg_timer *tmp_timer, *del_tmp;
433 
434 	list_for_each_entry_safe(tmp_timer, del_tmp, &active_timers, list)
435 		if (tmp_timer == timer)
436 			list_del(&timer->list);
437 }
438 
439 static void fsl_otg_fsm_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer t)
440 {
441 	struct fsl_otg_timer *timer;
442 
443 	timer = fsl_otg_get_timer(t);
444 	if (!timer)
445 		return;
446 
447 	fsl_otg_del_timer(fsm, timer);
448 }
449 
450 /* Reset controller, not reset the bus */
451 void otg_reset_controller(void)
452 {
453 	u32 command;
454 
455 	command = fsl_readl(&usb_dr_regs->usbcmd);
456 	command |= (1 << 1);
457 	fsl_writel(command, &usb_dr_regs->usbcmd);
458 	while (fsl_readl(&usb_dr_regs->usbcmd) & (1 << 1))
459 		;
460 }
461 
462 /* Call suspend/resume routines in host driver */
463 int fsl_otg_start_host(struct otg_fsm *fsm, int on)
464 {
465 	struct usb_otg *otg = fsm->otg;
466 	struct device *dev;
467 	struct fsl_otg *otg_dev =
468 		container_of(otg->usb_phy, struct fsl_otg, phy);
469 	u32 retval = 0;
470 
471 	if (!otg->host)
472 		return -ENODEV;
473 	dev = otg->host->controller;
474 
475 	/*
476 	 * Update a_vbus_vld state as a_vbus_vld int is disabled
477 	 * in device mode
478 	 */
479 	fsm->a_vbus_vld =
480 		!!(fsl_readl(&usb_dr_regs->otgsc) & OTGSC_STS_A_VBUS_VALID);
481 	if (on) {
482 		/* start fsl usb host controller */
483 		if (otg_dev->host_working)
484 			goto end;
485 		else {
486 			otg_reset_controller();
487 			VDBG("host on......\n");
488 			if (dev->driver->pm && dev->driver->pm->resume) {
489 				retval = dev->driver->pm->resume(dev);
490 				if (fsm->id) {
491 					/* default-b */
492 					fsl_otg_drv_vbus(fsm, 1);
493 					/*
494 					 * Workaround: b_host can't driver
495 					 * vbus, but PP in PORTSC needs to
496 					 * be 1 for host to work.
497 					 * So we set drv_vbus bit in
498 					 * transceiver to 0 thru ULPI.
499 					 */
500 					write_ulpi(0x0c, 0x20);
501 				}
502 			}
503 
504 			otg_dev->host_working = 1;
505 		}
506 	} else {
507 		/* stop fsl usb host controller */
508 		if (!otg_dev->host_working)
509 			goto end;
510 		else {
511 			VDBG("host off......\n");
512 			if (dev && dev->driver) {
513 				if (dev->driver->pm && dev->driver->pm->suspend)
514 					retval = dev->driver->pm->suspend(dev);
515 				if (fsm->id)
516 					/* default-b */
517 					fsl_otg_drv_vbus(fsm, 0);
518 			}
519 			otg_dev->host_working = 0;
520 		}
521 	}
522 end:
523 	return retval;
524 }
525 
526 /*
527  * Call suspend and resume function in udc driver
528  * to stop and start udc driver.
529  */
530 int fsl_otg_start_gadget(struct otg_fsm *fsm, int on)
531 {
532 	struct usb_otg *otg = fsm->otg;
533 	struct device *dev;
534 
535 	if (!otg->gadget || !otg->gadget->dev.parent)
536 		return -ENODEV;
537 
538 	VDBG("gadget %s\n", on ? "on" : "off");
539 	dev = otg->gadget->dev.parent;
540 
541 	if (on) {
542 		if (dev->driver->resume)
543 			dev->driver->resume(dev);
544 	} else {
545 		if (dev->driver->suspend)
546 			dev->driver->suspend(dev, otg_suspend_state);
547 	}
548 
549 	return 0;
550 }
551 
552 /*
553  * Called by initialization code of host driver.  Register host controller
554  * to the OTG.  Suspend host for OTG role detection.
555  */
556 static int fsl_otg_set_host(struct usb_otg *otg, struct usb_bus *host)
557 {
558 	struct fsl_otg *otg_dev;
559 
560 	if (!otg)
561 		return -ENODEV;
562 
563 	otg_dev = container_of(otg->usb_phy, struct fsl_otg, phy);
564 	if (otg_dev != fsl_otg_dev)
565 		return -ENODEV;
566 
567 	otg->host = host;
568 
569 	otg_dev->fsm.a_bus_drop = 0;
570 	otg_dev->fsm.a_bus_req = 1;
571 
572 	if (host) {
573 		VDBG("host off......\n");
574 
575 		otg->host->otg_port = fsl_otg_initdata.otg_port;
576 		otg->host->is_b_host = otg_dev->fsm.id;
577 		/*
578 		 * must leave time for hub_wq to finish its thing
579 		 * before yanking the host driver out from under it,
580 		 * so suspend the host after a short delay.
581 		 */
582 		otg_dev->host_working = 1;
583 		schedule_delayed_work(&otg_dev->otg_event, 100);
584 		return 0;
585 	} else {
586 		/* host driver going away */
587 		if (!(fsl_readl(&otg_dev->dr_mem_map->otgsc) &
588 		      OTGSC_STS_USB_ID)) {
589 			/* Mini-A cable connected */
590 			struct otg_fsm *fsm = &otg_dev->fsm;
591 
592 			otg->state = OTG_STATE_UNDEFINED;
593 			fsm->protocol = PROTO_UNDEF;
594 		}
595 	}
596 
597 	otg_dev->host_working = 0;
598 
599 	otg_statemachine(&otg_dev->fsm);
600 
601 	return 0;
602 }
603 
604 /* Called by initialization code of udc.  Register udc to OTG. */
605 static int fsl_otg_set_peripheral(struct usb_otg *otg,
606 					struct usb_gadget *gadget)
607 {
608 	struct fsl_otg *otg_dev;
609 
610 	if (!otg)
611 		return -ENODEV;
612 
613 	otg_dev = container_of(otg->usb_phy, struct fsl_otg, phy);
614 	VDBG("otg_dev 0x%x\n", (int)otg_dev);
615 	VDBG("fsl_otg_dev 0x%x\n", (int)fsl_otg_dev);
616 	if (otg_dev != fsl_otg_dev)
617 		return -ENODEV;
618 
619 	if (!gadget) {
620 		if (!otg->default_a)
621 			otg->gadget->ops->vbus_draw(otg->gadget, 0);
622 		usb_gadget_vbus_disconnect(otg->gadget);
623 		otg->gadget = 0;
624 		otg_dev->fsm.b_bus_req = 0;
625 		otg_statemachine(&otg_dev->fsm);
626 		return 0;
627 	}
628 
629 	otg->gadget = gadget;
630 	otg->gadget->is_a_peripheral = !otg_dev->fsm.id;
631 
632 	otg_dev->fsm.b_bus_req = 1;
633 
634 	/* start the gadget right away if the ID pin says Mini-B */
635 	pr_debug("ID pin=%d\n", otg_dev->fsm.id);
636 	if (otg_dev->fsm.id == 1) {
637 		fsl_otg_start_host(&otg_dev->fsm, 0);
638 		otg_drv_vbus(&otg_dev->fsm, 0);
639 		fsl_otg_start_gadget(&otg_dev->fsm, 1);
640 	}
641 
642 	return 0;
643 }
644 
645 /* Set OTG port power, only for B-device */
646 static int fsl_otg_set_power(struct usb_phy *phy, unsigned mA)
647 {
648 	if (!fsl_otg_dev)
649 		return -ENODEV;
650 	if (phy->otg->state == OTG_STATE_B_PERIPHERAL)
651 		pr_info("FSL OTG: Draw %d mA\n", mA);
652 
653 	return 0;
654 }
655 
656 /*
657  * Delayed pin detect interrupt processing.
658  *
659  * When the Mini-A cable is disconnected from the board,
660  * the pin-detect interrupt happens before the disconnect
661  * interrupts for the connected device(s).  In order to
662  * process the disconnect interrupt(s) prior to switching
663  * roles, the pin-detect interrupts are delayed, and handled
664  * by this routine.
665  */
666 static void fsl_otg_event(struct work_struct *work)
667 {
668 	struct fsl_otg *og = container_of(work, struct fsl_otg, otg_event.work);
669 	struct otg_fsm *fsm = &og->fsm;
670 
671 	if (fsm->id) {		/* switch to gadget */
672 		fsl_otg_start_host(fsm, 0);
673 		otg_drv_vbus(fsm, 0);
674 		fsl_otg_start_gadget(fsm, 1);
675 	}
676 }
677 
678 /* B-device start SRP */
679 static int fsl_otg_start_srp(struct usb_otg *otg)
680 {
681 	struct fsl_otg *otg_dev;
682 
683 	if (!otg || otg->state != OTG_STATE_B_IDLE)
684 		return -ENODEV;
685 
686 	otg_dev = container_of(otg->usb_phy, struct fsl_otg, phy);
687 	if (otg_dev != fsl_otg_dev)
688 		return -ENODEV;
689 
690 	otg_dev->fsm.b_bus_req = 1;
691 	otg_statemachine(&otg_dev->fsm);
692 
693 	return 0;
694 }
695 
696 /* A_host suspend will call this function to start hnp */
697 static int fsl_otg_start_hnp(struct usb_otg *otg)
698 {
699 	struct fsl_otg *otg_dev;
700 
701 	if (!otg)
702 		return -ENODEV;
703 
704 	otg_dev = container_of(otg->usb_phy, struct fsl_otg, phy);
705 	if (otg_dev != fsl_otg_dev)
706 		return -ENODEV;
707 
708 	pr_debug("start_hnp...\n");
709 
710 	/* clear a_bus_req to enter a_suspend state */
711 	otg_dev->fsm.a_bus_req = 0;
712 	otg_statemachine(&otg_dev->fsm);
713 
714 	return 0;
715 }
716 
717 /*
718  * Interrupt handler.  OTG/host/peripheral share the same int line.
719  * OTG driver clears OTGSC interrupts and leaves USB interrupts
720  * intact.  It needs to have knowledge of some USB interrupts
721  * such as port change.
722  */
723 irqreturn_t fsl_otg_isr(int irq, void *dev_id)
724 {
725 	struct otg_fsm *fsm = &((struct fsl_otg *)dev_id)->fsm;
726 	struct usb_otg *otg = ((struct fsl_otg *)dev_id)->phy.otg;
727 	u32 otg_int_src, otg_sc;
728 
729 	otg_sc = fsl_readl(&usb_dr_regs->otgsc);
730 	otg_int_src = otg_sc & OTGSC_INTSTS_MASK & (otg_sc >> 8);
731 
732 	/* Only clear otg interrupts */
733 	fsl_writel(otg_sc, &usb_dr_regs->otgsc);
734 
735 	/*FIXME: ID change not generate when init to 0 */
736 	fsm->id = (otg_sc & OTGSC_STS_USB_ID) ? 1 : 0;
737 	otg->default_a = (fsm->id == 0);
738 
739 	/* process OTG interrupts */
740 	if (otg_int_src) {
741 		if (otg_int_src & OTGSC_INTSTS_USB_ID) {
742 			fsm->id = (otg_sc & OTGSC_STS_USB_ID) ? 1 : 0;
743 			otg->default_a = (fsm->id == 0);
744 			/* clear conn information */
745 			if (fsm->id)
746 				fsm->b_conn = 0;
747 			else
748 				fsm->a_conn = 0;
749 
750 			if (otg->host)
751 				otg->host->is_b_host = fsm->id;
752 			if (otg->gadget)
753 				otg->gadget->is_a_peripheral = !fsm->id;
754 			VDBG("ID int (ID is %d)\n", fsm->id);
755 
756 			if (fsm->id) {	/* switch to gadget */
757 				schedule_delayed_work(
758 					&((struct fsl_otg *)dev_id)->otg_event,
759 					100);
760 			} else {	/* switch to host */
761 				cancel_delayed_work(&
762 						    ((struct fsl_otg *)dev_id)->
763 						    otg_event);
764 				fsl_otg_start_gadget(fsm, 0);
765 				otg_drv_vbus(fsm, 1);
766 				fsl_otg_start_host(fsm, 1);
767 			}
768 			return IRQ_HANDLED;
769 		}
770 	}
771 	return IRQ_NONE;
772 }
773 
774 static struct otg_fsm_ops fsl_otg_ops = {
775 	.chrg_vbus = fsl_otg_chrg_vbus,
776 	.drv_vbus = fsl_otg_drv_vbus,
777 	.loc_conn = fsl_otg_loc_conn,
778 	.loc_sof = fsl_otg_loc_sof,
779 	.start_pulse = fsl_otg_start_pulse,
780 
781 	.add_timer = fsl_otg_fsm_add_timer,
782 	.del_timer = fsl_otg_fsm_del_timer,
783 
784 	.start_host = fsl_otg_start_host,
785 	.start_gadget = fsl_otg_start_gadget,
786 };
787 
788 /* Initialize the global variable fsl_otg_dev and request IRQ for OTG */
789 static int fsl_otg_conf(struct platform_device *pdev)
790 {
791 	struct fsl_otg *fsl_otg_tc;
792 	int status;
793 
794 	if (fsl_otg_dev)
795 		return 0;
796 
797 	/* allocate space to fsl otg device */
798 	fsl_otg_tc = kzalloc(sizeof(struct fsl_otg), GFP_KERNEL);
799 	if (!fsl_otg_tc)
800 		return -ENOMEM;
801 
802 	fsl_otg_tc->phy.otg = kzalloc(sizeof(struct usb_otg), GFP_KERNEL);
803 	if (!fsl_otg_tc->phy.otg) {
804 		kfree(fsl_otg_tc);
805 		return -ENOMEM;
806 	}
807 
808 	INIT_DELAYED_WORK(&fsl_otg_tc->otg_event, fsl_otg_event);
809 
810 	INIT_LIST_HEAD(&active_timers);
811 	status = fsl_otg_init_timers(&fsl_otg_tc->fsm);
812 	if (status) {
813 		pr_info("Couldn't init OTG timers\n");
814 		goto err;
815 	}
816 	mutex_init(&fsl_otg_tc->fsm.lock);
817 
818 	/* Set OTG state machine operations */
819 	fsl_otg_tc->fsm.ops = &fsl_otg_ops;
820 
821 	/* initialize the otg structure */
822 	fsl_otg_tc->phy.label = DRIVER_DESC;
823 	fsl_otg_tc->phy.dev = &pdev->dev;
824 	fsl_otg_tc->phy.set_power = fsl_otg_set_power;
825 
826 	fsl_otg_tc->phy.otg->usb_phy = &fsl_otg_tc->phy;
827 	fsl_otg_tc->phy.otg->set_host = fsl_otg_set_host;
828 	fsl_otg_tc->phy.otg->set_peripheral = fsl_otg_set_peripheral;
829 	fsl_otg_tc->phy.otg->start_hnp = fsl_otg_start_hnp;
830 	fsl_otg_tc->phy.otg->start_srp = fsl_otg_start_srp;
831 
832 	fsl_otg_dev = fsl_otg_tc;
833 
834 	/* Store the otg transceiver */
835 	status = usb_add_phy(&fsl_otg_tc->phy, USB_PHY_TYPE_USB2);
836 	if (status) {
837 		pr_warn(FSL_OTG_NAME ": unable to register OTG transceiver.\n");
838 		goto err;
839 	}
840 
841 	return 0;
842 err:
843 	fsl_otg_uninit_timers();
844 	kfree(fsl_otg_tc->phy.otg);
845 	kfree(fsl_otg_tc);
846 	return status;
847 }
848 
849 /* OTG Initialization */
850 int usb_otg_start(struct platform_device *pdev)
851 {
852 	struct fsl_otg *p_otg;
853 	struct usb_phy *otg_trans = usb_get_phy(USB_PHY_TYPE_USB2);
854 	struct otg_fsm *fsm;
855 	int status;
856 	struct resource *res;
857 	u32 temp;
858 	struct fsl_usb2_platform_data *pdata = dev_get_platdata(&pdev->dev);
859 
860 	p_otg = container_of(otg_trans, struct fsl_otg, phy);
861 	fsm = &p_otg->fsm;
862 
863 	/* Initialize the state machine structure with default values */
864 	SET_OTG_STATE(otg_trans, OTG_STATE_UNDEFINED);
865 	fsm->otg = p_otg->phy.otg;
866 
867 	/* We don't require predefined MEM/IRQ resource index */
868 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
869 	if (!res)
870 		return -ENXIO;
871 
872 	/* We don't request_mem_region here to enable resource sharing
873 	 * with host/device */
874 
875 	usb_dr_regs = ioremap(res->start, sizeof(struct usb_dr_mmap));
876 	p_otg->dr_mem_map = (struct usb_dr_mmap *)usb_dr_regs;
877 	pdata->regs = (void *)usb_dr_regs;
878 
879 	if (pdata->init && pdata->init(pdev) != 0)
880 		return -EINVAL;
881 
882 	if (pdata->big_endian_mmio) {
883 		_fsl_readl = _fsl_readl_be;
884 		_fsl_writel = _fsl_writel_be;
885 	} else {
886 		_fsl_readl = _fsl_readl_le;
887 		_fsl_writel = _fsl_writel_le;
888 	}
889 
890 	/* request irq */
891 	p_otg->irq = platform_get_irq(pdev, 0);
892 	status = request_irq(p_otg->irq, fsl_otg_isr,
893 				IRQF_SHARED, driver_name, p_otg);
894 	if (status) {
895 		dev_dbg(p_otg->phy.dev, "can't get IRQ %d, error %d\n",
896 			p_otg->irq, status);
897 		iounmap(p_otg->dr_mem_map);
898 		kfree(p_otg->phy.otg);
899 		kfree(p_otg);
900 		return status;
901 	}
902 
903 	/* stop the controller */
904 	temp = fsl_readl(&p_otg->dr_mem_map->usbcmd);
905 	temp &= ~USB_CMD_RUN_STOP;
906 	fsl_writel(temp, &p_otg->dr_mem_map->usbcmd);
907 
908 	/* reset the controller */
909 	temp = fsl_readl(&p_otg->dr_mem_map->usbcmd);
910 	temp |= USB_CMD_CTRL_RESET;
911 	fsl_writel(temp, &p_otg->dr_mem_map->usbcmd);
912 
913 	/* wait reset completed */
914 	while (fsl_readl(&p_otg->dr_mem_map->usbcmd) & USB_CMD_CTRL_RESET)
915 		;
916 
917 	/* configure the VBUSHS as IDLE(both host and device) */
918 	temp = USB_MODE_STREAM_DISABLE | (pdata->es ? USB_MODE_ES : 0);
919 	fsl_writel(temp, &p_otg->dr_mem_map->usbmode);
920 
921 	/* configure PHY interface */
922 	temp = fsl_readl(&p_otg->dr_mem_map->portsc);
923 	temp &= ~(PORTSC_PHY_TYPE_SEL | PORTSC_PTW);
924 	switch (pdata->phy_mode) {
925 	case FSL_USB2_PHY_ULPI:
926 		temp |= PORTSC_PTS_ULPI;
927 		break;
928 	case FSL_USB2_PHY_UTMI_WIDE:
929 		temp |= PORTSC_PTW_16BIT;
930 		/* fall through */
931 	case FSL_USB2_PHY_UTMI:
932 		temp |= PORTSC_PTS_UTMI;
933 		/* fall through */
934 	default:
935 		break;
936 	}
937 	fsl_writel(temp, &p_otg->dr_mem_map->portsc);
938 
939 	if (pdata->have_sysif_regs) {
940 		/* configure control enable IO output, big endian register */
941 		temp = __raw_readl(&p_otg->dr_mem_map->control);
942 		temp |= USB_CTRL_IOENB;
943 		__raw_writel(temp, &p_otg->dr_mem_map->control);
944 	}
945 
946 	/* disable all interrupt and clear all OTGSC status */
947 	temp = fsl_readl(&p_otg->dr_mem_map->otgsc);
948 	temp &= ~OTGSC_INTERRUPT_ENABLE_BITS_MASK;
949 	temp |= OTGSC_INTERRUPT_STATUS_BITS_MASK | OTGSC_CTRL_VBUS_DISCHARGE;
950 	fsl_writel(temp, &p_otg->dr_mem_map->otgsc);
951 
952 	/*
953 	 * The identification (id) input is FALSE when a Mini-A plug is inserted
954 	 * in the devices Mini-AB receptacle. Otherwise, this input is TRUE.
955 	 * Also: record initial state of ID pin
956 	 */
957 	if (fsl_readl(&p_otg->dr_mem_map->otgsc) & OTGSC_STS_USB_ID) {
958 		p_otg->phy.otg->state = OTG_STATE_UNDEFINED;
959 		p_otg->fsm.id = 1;
960 	} else {
961 		p_otg->phy.otg->state = OTG_STATE_A_IDLE;
962 		p_otg->fsm.id = 0;
963 	}
964 
965 	pr_debug("initial ID pin=%d\n", p_otg->fsm.id);
966 
967 	/* enable OTG ID pin interrupt */
968 	temp = fsl_readl(&p_otg->dr_mem_map->otgsc);
969 	temp |= OTGSC_INTR_USB_ID_EN;
970 	temp &= ~(OTGSC_CTRL_VBUS_DISCHARGE | OTGSC_INTR_1MS_TIMER_EN);
971 	fsl_writel(temp, &p_otg->dr_mem_map->otgsc);
972 
973 	return 0;
974 }
975 
976 /*
977  * state file in sysfs
978  */
979 static int show_fsl_usb2_otg_state(struct device *dev,
980 				   struct device_attribute *attr, char *buf)
981 {
982 	struct otg_fsm *fsm = &fsl_otg_dev->fsm;
983 	char *next = buf;
984 	unsigned size = PAGE_SIZE;
985 	int t;
986 
987 	mutex_lock(&fsm->lock);
988 
989 	/* basic driver infomation */
990 	t = scnprintf(next, size,
991 			DRIVER_DESC "\n" "fsl_usb2_otg version: %s\n\n",
992 			DRIVER_VERSION);
993 	size -= t;
994 	next += t;
995 
996 	/* Registers */
997 	t = scnprintf(next, size,
998 			"OTGSC:   0x%08x\n"
999 			"PORTSC:  0x%08x\n"
1000 			"USBMODE: 0x%08x\n"
1001 			"USBCMD:  0x%08x\n"
1002 			"USBSTS:  0x%08x\n"
1003 			"USBINTR: 0x%08x\n",
1004 			fsl_readl(&usb_dr_regs->otgsc),
1005 			fsl_readl(&usb_dr_regs->portsc),
1006 			fsl_readl(&usb_dr_regs->usbmode),
1007 			fsl_readl(&usb_dr_regs->usbcmd),
1008 			fsl_readl(&usb_dr_regs->usbsts),
1009 			fsl_readl(&usb_dr_regs->usbintr));
1010 	size -= t;
1011 	next += t;
1012 
1013 	/* State */
1014 	t = scnprintf(next, size,
1015 		      "OTG state: %s\n\n",
1016 		      usb_otg_state_string(fsl_otg_dev->phy.otg->state));
1017 	size -= t;
1018 	next += t;
1019 
1020 	/* State Machine Variables */
1021 	t = scnprintf(next, size,
1022 			"a_bus_req: %d\n"
1023 			"b_bus_req: %d\n"
1024 			"a_bus_resume: %d\n"
1025 			"a_bus_suspend: %d\n"
1026 			"a_conn: %d\n"
1027 			"a_sess_vld: %d\n"
1028 			"a_srp_det: %d\n"
1029 			"a_vbus_vld: %d\n"
1030 			"b_bus_resume: %d\n"
1031 			"b_bus_suspend: %d\n"
1032 			"b_conn: %d\n"
1033 			"b_se0_srp: %d\n"
1034 			"b_ssend_srp: %d\n"
1035 			"b_sess_vld: %d\n"
1036 			"id: %d\n",
1037 			fsm->a_bus_req,
1038 			fsm->b_bus_req,
1039 			fsm->a_bus_resume,
1040 			fsm->a_bus_suspend,
1041 			fsm->a_conn,
1042 			fsm->a_sess_vld,
1043 			fsm->a_srp_det,
1044 			fsm->a_vbus_vld,
1045 			fsm->b_bus_resume,
1046 			fsm->b_bus_suspend,
1047 			fsm->b_conn,
1048 			fsm->b_se0_srp,
1049 			fsm->b_ssend_srp,
1050 			fsm->b_sess_vld,
1051 			fsm->id);
1052 	size -= t;
1053 	next += t;
1054 
1055 	mutex_unlock(&fsm->lock);
1056 
1057 	return PAGE_SIZE - size;
1058 }
1059 
1060 static DEVICE_ATTR(fsl_usb2_otg_state, S_IRUGO, show_fsl_usb2_otg_state, NULL);
1061 
1062 
1063 /* Char driver interface to control some OTG input */
1064 
1065 /*
1066  * Handle some ioctl command, such as get otg
1067  * status and set host suspend
1068  */
1069 static long fsl_otg_ioctl(struct file *file, unsigned int cmd,
1070 			  unsigned long arg)
1071 {
1072 	u32 retval = 0;
1073 
1074 	switch (cmd) {
1075 	case GET_OTG_STATUS:
1076 		retval = fsl_otg_dev->host_working;
1077 		break;
1078 
1079 	case SET_A_SUSPEND_REQ:
1080 		fsl_otg_dev->fsm.a_suspend_req_inf = arg;
1081 		break;
1082 
1083 	case SET_A_BUS_DROP:
1084 		fsl_otg_dev->fsm.a_bus_drop = arg;
1085 		break;
1086 
1087 	case SET_A_BUS_REQ:
1088 		fsl_otg_dev->fsm.a_bus_req = arg;
1089 		break;
1090 
1091 	case SET_B_BUS_REQ:
1092 		fsl_otg_dev->fsm.b_bus_req = arg;
1093 		break;
1094 
1095 	default:
1096 		break;
1097 	}
1098 
1099 	otg_statemachine(&fsl_otg_dev->fsm);
1100 
1101 	return retval;
1102 }
1103 
1104 static int fsl_otg_open(struct inode *inode, struct file *file)
1105 {
1106 	return 0;
1107 }
1108 
1109 static int fsl_otg_release(struct inode *inode, struct file *file)
1110 {
1111 	return 0;
1112 }
1113 
1114 static const struct file_operations otg_fops = {
1115 	.owner = THIS_MODULE,
1116 	.llseek = NULL,
1117 	.read = NULL,
1118 	.write = NULL,
1119 	.unlocked_ioctl = fsl_otg_ioctl,
1120 	.open = fsl_otg_open,
1121 	.release = fsl_otg_release,
1122 };
1123 
1124 static int fsl_otg_probe(struct platform_device *pdev)
1125 {
1126 	int ret;
1127 
1128 	if (!dev_get_platdata(&pdev->dev))
1129 		return -ENODEV;
1130 
1131 	/* configure the OTG */
1132 	ret = fsl_otg_conf(pdev);
1133 	if (ret) {
1134 		dev_err(&pdev->dev, "Couldn't configure OTG module\n");
1135 		return ret;
1136 	}
1137 
1138 	/* start OTG */
1139 	ret = usb_otg_start(pdev);
1140 	if (ret) {
1141 		dev_err(&pdev->dev, "Can't init FSL OTG device\n");
1142 		return ret;
1143 	}
1144 
1145 	ret = register_chrdev(FSL_OTG_MAJOR, FSL_OTG_NAME, &otg_fops);
1146 	if (ret) {
1147 		dev_err(&pdev->dev, "unable to register FSL OTG device\n");
1148 		return ret;
1149 	}
1150 
1151 	ret = device_create_file(&pdev->dev, &dev_attr_fsl_usb2_otg_state);
1152 	if (ret)
1153 		dev_warn(&pdev->dev, "Can't register sysfs attribute\n");
1154 
1155 	return ret;
1156 }
1157 
1158 static int fsl_otg_remove(struct platform_device *pdev)
1159 {
1160 	struct fsl_usb2_platform_data *pdata = dev_get_platdata(&pdev->dev);
1161 
1162 	usb_remove_phy(&fsl_otg_dev->phy);
1163 	free_irq(fsl_otg_dev->irq, fsl_otg_dev);
1164 
1165 	iounmap((void *)usb_dr_regs);
1166 
1167 	fsl_otg_uninit_timers();
1168 	kfree(fsl_otg_dev->phy.otg);
1169 	kfree(fsl_otg_dev);
1170 
1171 	device_remove_file(&pdev->dev, &dev_attr_fsl_usb2_otg_state);
1172 
1173 	unregister_chrdev(FSL_OTG_MAJOR, FSL_OTG_NAME);
1174 
1175 	if (pdata->exit)
1176 		pdata->exit(pdev);
1177 
1178 	return 0;
1179 }
1180 
1181 struct platform_driver fsl_otg_driver = {
1182 	.probe = fsl_otg_probe,
1183 	.remove = fsl_otg_remove,
1184 	.driver = {
1185 		.name = driver_name,
1186 		.owner = THIS_MODULE,
1187 	},
1188 };
1189 
1190 module_platform_driver(fsl_otg_driver);
1191 
1192 MODULE_DESCRIPTION(DRIVER_INFO);
1193 MODULE_AUTHOR(DRIVER_AUTHOR);
1194 MODULE_LICENSE("GPL");
1195