xref: /openbmc/linux/drivers/usb/musb/musb_virthub.c (revision 82003e04)
1 /*
2  * MUSB OTG driver virtual root hub support
3  *
4  * Copyright 2005 Mentor Graphics Corporation
5  * Copyright (C) 2005-2006 by Texas Instruments
6  * Copyright (C) 2006-2007 Nokia Corporation
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * version 2 as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  * General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20  * 02110-1301 USA
21  *
22  * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
23  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
25  * NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
28  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
29  * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  *
33  */
34 
35 #include <linux/module.h>
36 #include <linux/kernel.h>
37 #include <linux/sched.h>
38 #include <linux/errno.h>
39 #include <linux/time.h>
40 #include <linux/timer.h>
41 
42 #include <asm/unaligned.h>
43 
44 #include "musb_core.h"
45 
46 void musb_host_finish_resume(struct work_struct *work)
47 {
48 	struct musb *musb;
49 	unsigned long flags;
50 	u8 power;
51 
52 	musb = container_of(work, struct musb, finish_resume_work.work);
53 
54 	spin_lock_irqsave(&musb->lock, flags);
55 
56 	power = musb_readb(musb->mregs, MUSB_POWER);
57 	power &= ~MUSB_POWER_RESUME;
58 	musb_dbg(musb, "root port resume stopped, power %02x", power);
59 	musb_writeb(musb->mregs, MUSB_POWER, power);
60 
61 	/*
62 	 * ISSUE:  DaVinci (RTL 1.300) disconnects after
63 	 * resume of high speed peripherals (but not full
64 	 * speed ones).
65 	 */
66 	musb->is_active = 1;
67 	musb->port1_status &= ~(USB_PORT_STAT_SUSPEND | MUSB_PORT_STAT_RESUME);
68 	musb->port1_status |= USB_PORT_STAT_C_SUSPEND << 16;
69 	usb_hcd_poll_rh_status(musb->hcd);
70 	/* NOTE: it might really be A_WAIT_BCON ... */
71 	musb->xceiv->otg->state = OTG_STATE_A_HOST;
72 
73 	spin_unlock_irqrestore(&musb->lock, flags);
74 }
75 
76 void musb_port_suspend(struct musb *musb, bool do_suspend)
77 {
78 	struct usb_otg	*otg = musb->xceiv->otg;
79 	u8		power;
80 	void __iomem	*mbase = musb->mregs;
81 
82 	if (!is_host_active(musb))
83 		return;
84 
85 	/* NOTE:  this doesn't necessarily put PHY into low power mode,
86 	 * turning off its clock; that's a function of PHY integration and
87 	 * MUSB_POWER_ENSUSPEND.  PHY may need a clock (sigh) to detect
88 	 * SE0 changing to connect (J) or wakeup (K) states.
89 	 */
90 	power = musb_readb(mbase, MUSB_POWER);
91 	if (do_suspend) {
92 		int retries = 10000;
93 
94 		power &= ~MUSB_POWER_RESUME;
95 		power |= MUSB_POWER_SUSPENDM;
96 		musb_writeb(mbase, MUSB_POWER, power);
97 
98 		/* Needed for OPT A tests */
99 		power = musb_readb(mbase, MUSB_POWER);
100 		while (power & MUSB_POWER_SUSPENDM) {
101 			power = musb_readb(mbase, MUSB_POWER);
102 			if (retries-- < 1)
103 				break;
104 		}
105 
106 		musb_dbg(musb, "Root port suspended, power %02x", power);
107 
108 		musb->port1_status |= USB_PORT_STAT_SUSPEND;
109 		switch (musb->xceiv->otg->state) {
110 		case OTG_STATE_A_HOST:
111 			musb->xceiv->otg->state = OTG_STATE_A_SUSPEND;
112 			musb->is_active = otg->host->b_hnp_enable;
113 			if (musb->is_active)
114 				mod_timer(&musb->otg_timer, jiffies
115 					+ msecs_to_jiffies(
116 						OTG_TIME_A_AIDL_BDIS));
117 			musb_platform_try_idle(musb, 0);
118 			break;
119 		case OTG_STATE_B_HOST:
120 			musb->xceiv->otg->state = OTG_STATE_B_WAIT_ACON;
121 			musb->is_active = otg->host->b_hnp_enable;
122 			musb_platform_try_idle(musb, 0);
123 			break;
124 		default:
125 			musb_dbg(musb, "bogus rh suspend? %s",
126 				usb_otg_state_string(musb->xceiv->otg->state));
127 		}
128 	} else if (power & MUSB_POWER_SUSPENDM) {
129 		power &= ~MUSB_POWER_SUSPENDM;
130 		power |= MUSB_POWER_RESUME;
131 		musb_writeb(mbase, MUSB_POWER, power);
132 
133 		musb_dbg(musb, "Root port resuming, power %02x", power);
134 
135 		/* later, GetPortStatus will stop RESUME signaling */
136 		musb->port1_status |= MUSB_PORT_STAT_RESUME;
137 		schedule_delayed_work(&musb->finish_resume_work,
138 				      msecs_to_jiffies(USB_RESUME_TIMEOUT));
139 	}
140 }
141 
142 void musb_port_reset(struct musb *musb, bool do_reset)
143 {
144 	u8		power;
145 	void __iomem	*mbase = musb->mregs;
146 
147 	if (musb->xceiv->otg->state == OTG_STATE_B_IDLE) {
148 		musb_dbg(musb, "HNP: Returning from HNP; no hub reset from b_idle");
149 		musb->port1_status &= ~USB_PORT_STAT_RESET;
150 		return;
151 	}
152 
153 	if (!is_host_active(musb))
154 		return;
155 
156 	/* NOTE:  caller guarantees it will turn off the reset when
157 	 * the appropriate amount of time has passed
158 	 */
159 	power = musb_readb(mbase, MUSB_POWER);
160 	if (do_reset) {
161 		/*
162 		 * If RESUME is set, we must make sure it stays minimum 20 ms.
163 		 * Then we must clear RESUME and wait a bit to let musb start
164 		 * generating SOFs. If we don't do this, OPT HS A 6.8 tests
165 		 * fail with "Error! Did not receive an SOF before suspend
166 		 * detected".
167 		 */
168 		if (power &  MUSB_POWER_RESUME) {
169 			long remain = (unsigned long) musb->rh_timer - jiffies;
170 
171 			if (musb->rh_timer > 0 && remain > 0) {
172 				/* take into account the minimum delay after resume */
173 				schedule_delayed_work(
174 					&musb->deassert_reset_work, remain);
175 				return;
176 			}
177 
178 			musb_writeb(mbase, MUSB_POWER,
179 				    power & ~MUSB_POWER_RESUME);
180 
181 			/* Give the core 1 ms to clear MUSB_POWER_RESUME */
182 			schedule_delayed_work(&musb->deassert_reset_work,
183 					      msecs_to_jiffies(1));
184 			return;
185 		}
186 
187 		power &= 0xf0;
188 		musb_writeb(mbase, MUSB_POWER,
189 				power | MUSB_POWER_RESET);
190 
191 		musb->port1_status |= USB_PORT_STAT_RESET;
192 		musb->port1_status &= ~USB_PORT_STAT_ENABLE;
193 		schedule_delayed_work(&musb->deassert_reset_work,
194 				      msecs_to_jiffies(50));
195 	} else {
196 		musb_dbg(musb, "root port reset stopped");
197 		musb_platform_pre_root_reset_end(musb);
198 		musb_writeb(mbase, MUSB_POWER,
199 				power & ~MUSB_POWER_RESET);
200 		musb_platform_post_root_reset_end(musb);
201 
202 		power = musb_readb(mbase, MUSB_POWER);
203 		if (power & MUSB_POWER_HSMODE) {
204 			musb_dbg(musb, "high-speed device connected");
205 			musb->port1_status |= USB_PORT_STAT_HIGH_SPEED;
206 		}
207 
208 		musb->port1_status &= ~USB_PORT_STAT_RESET;
209 		musb->port1_status |= USB_PORT_STAT_ENABLE
210 					| (USB_PORT_STAT_C_RESET << 16)
211 					| (USB_PORT_STAT_C_ENABLE << 16);
212 		usb_hcd_poll_rh_status(musb->hcd);
213 
214 		musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
215 	}
216 }
217 
218 void musb_root_disconnect(struct musb *musb)
219 {
220 	struct usb_otg	*otg = musb->xceiv->otg;
221 
222 	musb->port1_status = USB_PORT_STAT_POWER
223 			| (USB_PORT_STAT_C_CONNECTION << 16);
224 
225 	usb_hcd_poll_rh_status(musb->hcd);
226 	musb->is_active = 0;
227 
228 	switch (musb->xceiv->otg->state) {
229 	case OTG_STATE_A_SUSPEND:
230 		if (otg->host->b_hnp_enable) {
231 			musb->xceiv->otg->state = OTG_STATE_A_PERIPHERAL;
232 			musb->g.is_a_peripheral = 1;
233 			break;
234 		}
235 		/* FALLTHROUGH */
236 	case OTG_STATE_A_HOST:
237 		musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
238 		musb->is_active = 0;
239 		break;
240 	case OTG_STATE_A_WAIT_VFALL:
241 		musb->xceiv->otg->state = OTG_STATE_B_IDLE;
242 		break;
243 	default:
244 		musb_dbg(musb, "host disconnect (%s)",
245 			usb_otg_state_string(musb->xceiv->otg->state));
246 	}
247 }
248 EXPORT_SYMBOL_GPL(musb_root_disconnect);
249 
250 
251 /*---------------------------------------------------------------------*/
252 
253 /* Caller may or may not hold musb->lock */
254 int musb_hub_status_data(struct usb_hcd *hcd, char *buf)
255 {
256 	struct musb	*musb = hcd_to_musb(hcd);
257 	int		retval = 0;
258 
259 	/* called in_irq() via usb_hcd_poll_rh_status() */
260 	if (musb->port1_status & 0xffff0000) {
261 		*buf = 0x02;
262 		retval = 1;
263 	}
264 	return retval;
265 }
266 
267 static int musb_has_gadget(struct musb *musb)
268 {
269 	/*
270 	 * In host-only mode we start a connection right away. In OTG mode
271 	 * we have to wait until we loaded a gadget. We don't really need a
272 	 * gadget if we operate as a host but we should not start a session
273 	 * as a device without a gadget or else we explode.
274 	 */
275 #ifdef CONFIG_USB_MUSB_HOST
276 	return 1;
277 #else
278 	return musb->port_mode == MUSB_PORT_MODE_HOST;
279 #endif
280 }
281 
282 int musb_hub_control(
283 	struct usb_hcd	*hcd,
284 	u16		typeReq,
285 	u16		wValue,
286 	u16		wIndex,
287 	char		*buf,
288 	u16		wLength)
289 {
290 	struct musb	*musb = hcd_to_musb(hcd);
291 	u32		temp;
292 	int		retval = 0;
293 	unsigned long	flags;
294 	bool		start_musb = false;
295 
296 	spin_lock_irqsave(&musb->lock, flags);
297 
298 	if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) {
299 		spin_unlock_irqrestore(&musb->lock, flags);
300 		return -ESHUTDOWN;
301 	}
302 
303 	/* hub features:  always zero, setting is a NOP
304 	 * port features: reported, sometimes updated when host is active
305 	 * no indicators
306 	 */
307 	switch (typeReq) {
308 	case ClearHubFeature:
309 	case SetHubFeature:
310 		switch (wValue) {
311 		case C_HUB_OVER_CURRENT:
312 		case C_HUB_LOCAL_POWER:
313 			break;
314 		default:
315 			goto error;
316 		}
317 		break;
318 	case ClearPortFeature:
319 		if ((wIndex & 0xff) != 1)
320 			goto error;
321 
322 		switch (wValue) {
323 		case USB_PORT_FEAT_ENABLE:
324 			break;
325 		case USB_PORT_FEAT_SUSPEND:
326 			musb_port_suspend(musb, false);
327 			break;
328 		case USB_PORT_FEAT_POWER:
329 			if (!hcd->self.is_b_host)
330 				musb_platform_set_vbus(musb, 0);
331 			break;
332 		case USB_PORT_FEAT_C_CONNECTION:
333 		case USB_PORT_FEAT_C_ENABLE:
334 		case USB_PORT_FEAT_C_OVER_CURRENT:
335 		case USB_PORT_FEAT_C_RESET:
336 		case USB_PORT_FEAT_C_SUSPEND:
337 			break;
338 		default:
339 			goto error;
340 		}
341 		musb_dbg(musb, "clear feature %d", wValue);
342 		musb->port1_status &= ~(1 << wValue);
343 		break;
344 	case GetHubDescriptor:
345 		{
346 		struct usb_hub_descriptor *desc = (void *)buf;
347 
348 		desc->bDescLength = 9;
349 		desc->bDescriptorType = USB_DT_HUB;
350 		desc->bNbrPorts = 1;
351 		desc->wHubCharacteristics = cpu_to_le16(
352 			HUB_CHAR_INDV_PORT_LPSM /* per-port power switching */
353 			| HUB_CHAR_NO_OCPM	/* no overcurrent reporting */
354 			);
355 		desc->bPwrOn2PwrGood = 5;	/* msec/2 */
356 		desc->bHubContrCurrent = 0;
357 
358 		/* workaround bogus struct definition */
359 		desc->u.hs.DeviceRemovable[0] = 0x02;	/* port 1 */
360 		desc->u.hs.DeviceRemovable[1] = 0xff;
361 		}
362 		break;
363 	case GetHubStatus:
364 		temp = 0;
365 		*(__le32 *) buf = cpu_to_le32(temp);
366 		break;
367 	case GetPortStatus:
368 		if (wIndex != 1)
369 			goto error;
370 
371 		put_unaligned(cpu_to_le32(musb->port1_status
372 					& ~MUSB_PORT_STAT_RESUME),
373 				(__le32 *) buf);
374 
375 		/* port change status is more interesting */
376 		musb_dbg(musb, "port status %08x", musb->port1_status);
377 		break;
378 	case SetPortFeature:
379 		if ((wIndex & 0xff) != 1)
380 			goto error;
381 
382 		switch (wValue) {
383 		case USB_PORT_FEAT_POWER:
384 			/* NOTE: this controller has a strange state machine
385 			 * that involves "requesting sessions" according to
386 			 * magic side effects from incompletely-described
387 			 * rules about startup...
388 			 *
389 			 * This call is what really starts the host mode; be
390 			 * very careful about side effects if you reorder any
391 			 * initialization logic, e.g. for OTG, or change any
392 			 * logic relating to VBUS power-up.
393 			 */
394 			if (!hcd->self.is_b_host && musb_has_gadget(musb))
395 				start_musb = true;
396 			break;
397 		case USB_PORT_FEAT_RESET:
398 			musb_port_reset(musb, true);
399 			break;
400 		case USB_PORT_FEAT_SUSPEND:
401 			musb_port_suspend(musb, true);
402 			break;
403 		case USB_PORT_FEAT_TEST:
404 			if (unlikely(is_host_active(musb)))
405 				goto error;
406 
407 			wIndex >>= 8;
408 			switch (wIndex) {
409 			case 1:
410 				pr_debug("TEST_J\n");
411 				temp = MUSB_TEST_J;
412 				break;
413 			case 2:
414 				pr_debug("TEST_K\n");
415 				temp = MUSB_TEST_K;
416 				break;
417 			case 3:
418 				pr_debug("TEST_SE0_NAK\n");
419 				temp = MUSB_TEST_SE0_NAK;
420 				break;
421 			case 4:
422 				pr_debug("TEST_PACKET\n");
423 				temp = MUSB_TEST_PACKET;
424 				musb_load_testpacket(musb);
425 				break;
426 			case 5:
427 				pr_debug("TEST_FORCE_ENABLE\n");
428 				temp = MUSB_TEST_FORCE_HOST
429 					| MUSB_TEST_FORCE_HS;
430 
431 				musb_writeb(musb->mregs, MUSB_DEVCTL,
432 						MUSB_DEVCTL_SESSION);
433 				break;
434 			case 6:
435 				pr_debug("TEST_FIFO_ACCESS\n");
436 				temp = MUSB_TEST_FIFO_ACCESS;
437 				break;
438 			default:
439 				goto error;
440 			}
441 			musb_writeb(musb->mregs, MUSB_TESTMODE, temp);
442 			break;
443 		default:
444 			goto error;
445 		}
446 		musb_dbg(musb, "set feature %d", wValue);
447 		musb->port1_status |= 1 << wValue;
448 		break;
449 
450 	default:
451 error:
452 		/* "protocol stall" on error */
453 		retval = -EPIPE;
454 	}
455 	spin_unlock_irqrestore(&musb->lock, flags);
456 
457 	if (start_musb)
458 		musb_start(musb);
459 
460 	return retval;
461 }
462