xref: /openbmc/linux/drivers/usb/musb/musb_virthub.c (revision 5d0e4d78)
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 		musb->port1_status |= MUSB_PORT_STAT_RESUME;
136 		schedule_delayed_work(&musb->finish_resume_work,
137 				      msecs_to_jiffies(USB_RESUME_TIMEOUT));
138 	}
139 }
140 
141 void musb_port_reset(struct musb *musb, bool do_reset)
142 {
143 	u8		power;
144 	void __iomem	*mbase = musb->mregs;
145 
146 	if (musb->xceiv->otg->state == OTG_STATE_B_IDLE) {
147 		musb_dbg(musb, "HNP: Returning from HNP; no hub reset from b_idle");
148 		musb->port1_status &= ~USB_PORT_STAT_RESET;
149 		return;
150 	}
151 
152 	if (!is_host_active(musb))
153 		return;
154 
155 	/* NOTE:  caller guarantees it will turn off the reset when
156 	 * the appropriate amount of time has passed
157 	 */
158 	power = musb_readb(mbase, MUSB_POWER);
159 	if (do_reset) {
160 		/*
161 		 * If RESUME is set, we must make sure it stays minimum 20 ms.
162 		 * Then we must clear RESUME and wait a bit to let musb start
163 		 * generating SOFs. If we don't do this, OPT HS A 6.8 tests
164 		 * fail with "Error! Did not receive an SOF before suspend
165 		 * detected".
166 		 */
167 		if (power &  MUSB_POWER_RESUME) {
168 			long remain = (unsigned long) musb->rh_timer - jiffies;
169 
170 			if (musb->rh_timer > 0 && remain > 0) {
171 				/* take into account the minimum delay after resume */
172 				schedule_delayed_work(
173 					&musb->deassert_reset_work, remain);
174 				return;
175 			}
176 
177 			musb_writeb(mbase, MUSB_POWER,
178 				    power & ~MUSB_POWER_RESUME);
179 
180 			/* Give the core 1 ms to clear MUSB_POWER_RESUME */
181 			schedule_delayed_work(&musb->deassert_reset_work,
182 					      msecs_to_jiffies(1));
183 			return;
184 		}
185 
186 		power &= 0xf0;
187 		musb_writeb(mbase, MUSB_POWER,
188 				power | MUSB_POWER_RESET);
189 
190 		musb->port1_status |= USB_PORT_STAT_RESET;
191 		musb->port1_status &= ~USB_PORT_STAT_ENABLE;
192 		schedule_delayed_work(&musb->deassert_reset_work,
193 				      msecs_to_jiffies(50));
194 	} else {
195 		musb_dbg(musb, "root port reset stopped");
196 		musb_platform_pre_root_reset_end(musb);
197 		musb_writeb(mbase, MUSB_POWER,
198 				power & ~MUSB_POWER_RESET);
199 		musb_platform_post_root_reset_end(musb);
200 
201 		power = musb_readb(mbase, MUSB_POWER);
202 		if (power & MUSB_POWER_HSMODE) {
203 			musb_dbg(musb, "high-speed device connected");
204 			musb->port1_status |= USB_PORT_STAT_HIGH_SPEED;
205 		}
206 
207 		musb->port1_status &= ~USB_PORT_STAT_RESET;
208 		musb->port1_status |= USB_PORT_STAT_ENABLE
209 					| (USB_PORT_STAT_C_RESET << 16)
210 					| (USB_PORT_STAT_C_ENABLE << 16);
211 		usb_hcd_poll_rh_status(musb->hcd);
212 
213 		musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
214 	}
215 }
216 
217 void musb_root_disconnect(struct musb *musb)
218 {
219 	struct usb_otg	*otg = musb->xceiv->otg;
220 
221 	musb->port1_status = USB_PORT_STAT_POWER
222 			| (USB_PORT_STAT_C_CONNECTION << 16);
223 
224 	usb_hcd_poll_rh_status(musb->hcd);
225 	musb->is_active = 0;
226 
227 	switch (musb->xceiv->otg->state) {
228 	case OTG_STATE_A_SUSPEND:
229 		if (otg->host->b_hnp_enable) {
230 			musb->xceiv->otg->state = OTG_STATE_A_PERIPHERAL;
231 			musb->g.is_a_peripheral = 1;
232 			break;
233 		}
234 		/* FALLTHROUGH */
235 	case OTG_STATE_A_HOST:
236 		musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
237 		musb->is_active = 0;
238 		break;
239 	case OTG_STATE_A_WAIT_VFALL:
240 		musb->xceiv->otg->state = OTG_STATE_B_IDLE;
241 		break;
242 	default:
243 		musb_dbg(musb, "host disconnect (%s)",
244 			usb_otg_state_string(musb->xceiv->otg->state));
245 	}
246 }
247 EXPORT_SYMBOL_GPL(musb_root_disconnect);
248 
249 
250 /*---------------------------------------------------------------------*/
251 
252 /* Caller may or may not hold musb->lock */
253 int musb_hub_status_data(struct usb_hcd *hcd, char *buf)
254 {
255 	struct musb	*musb = hcd_to_musb(hcd);
256 	int		retval = 0;
257 
258 	/* called in_irq() via usb_hcd_poll_rh_status() */
259 	if (musb->port1_status & 0xffff0000) {
260 		*buf = 0x02;
261 		retval = 1;
262 	}
263 	return retval;
264 }
265 
266 static int musb_has_gadget(struct musb *musb)
267 {
268 	/*
269 	 * In host-only mode we start a connection right away. In OTG mode
270 	 * we have to wait until we loaded a gadget. We don't really need a
271 	 * gadget if we operate as a host but we should not start a session
272 	 * as a device without a gadget or else we explode.
273 	 */
274 #ifdef CONFIG_USB_MUSB_HOST
275 	return 1;
276 #else
277 	return musb->port_mode == MUSB_PORT_MODE_HOST;
278 #endif
279 }
280 
281 int musb_hub_control(
282 	struct usb_hcd	*hcd,
283 	u16		typeReq,
284 	u16		wValue,
285 	u16		wIndex,
286 	char		*buf,
287 	u16		wLength)
288 {
289 	struct musb	*musb = hcd_to_musb(hcd);
290 	u32		temp;
291 	int		retval = 0;
292 	unsigned long	flags;
293 	bool		start_musb = false;
294 
295 	spin_lock_irqsave(&musb->lock, flags);
296 
297 	if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) {
298 		spin_unlock_irqrestore(&musb->lock, flags);
299 		return -ESHUTDOWN;
300 	}
301 
302 	/* hub features:  always zero, setting is a NOP
303 	 * port features: reported, sometimes updated when host is active
304 	 * no indicators
305 	 */
306 	switch (typeReq) {
307 	case ClearHubFeature:
308 	case SetHubFeature:
309 		switch (wValue) {
310 		case C_HUB_OVER_CURRENT:
311 		case C_HUB_LOCAL_POWER:
312 			break;
313 		default:
314 			goto error;
315 		}
316 		break;
317 	case ClearPortFeature:
318 		if ((wIndex & 0xff) != 1)
319 			goto error;
320 
321 		switch (wValue) {
322 		case USB_PORT_FEAT_ENABLE:
323 			break;
324 		case USB_PORT_FEAT_SUSPEND:
325 			musb_port_suspend(musb, false);
326 			break;
327 		case USB_PORT_FEAT_POWER:
328 			if (!hcd->self.is_b_host)
329 				musb_platform_set_vbus(musb, 0);
330 			break;
331 		case USB_PORT_FEAT_C_CONNECTION:
332 		case USB_PORT_FEAT_C_ENABLE:
333 		case USB_PORT_FEAT_C_OVER_CURRENT:
334 		case USB_PORT_FEAT_C_RESET:
335 		case USB_PORT_FEAT_C_SUSPEND:
336 			break;
337 		default:
338 			goto error;
339 		}
340 		musb_dbg(musb, "clear feature %d", wValue);
341 		musb->port1_status &= ~(1 << wValue);
342 		break;
343 	case GetHubDescriptor:
344 		{
345 		struct usb_hub_descriptor *desc = (void *)buf;
346 
347 		desc->bDescLength = 9;
348 		desc->bDescriptorType = USB_DT_HUB;
349 		desc->bNbrPorts = 1;
350 		desc->wHubCharacteristics = cpu_to_le16(
351 			HUB_CHAR_INDV_PORT_LPSM /* per-port power switching */
352 			| HUB_CHAR_NO_OCPM	/* no overcurrent reporting */
353 			);
354 		desc->bPwrOn2PwrGood = 5;	/* msec/2 */
355 		desc->bHubContrCurrent = 0;
356 
357 		/* workaround bogus struct definition */
358 		desc->u.hs.DeviceRemovable[0] = 0x02;	/* port 1 */
359 		desc->u.hs.DeviceRemovable[1] = 0xff;
360 		}
361 		break;
362 	case GetHubStatus:
363 		temp = 0;
364 		*(__le32 *) buf = cpu_to_le32(temp);
365 		break;
366 	case GetPortStatus:
367 		if (wIndex != 1)
368 			goto error;
369 
370 		put_unaligned(cpu_to_le32(musb->port1_status
371 					& ~MUSB_PORT_STAT_RESUME),
372 				(__le32 *) buf);
373 
374 		/* port change status is more interesting */
375 		musb_dbg(musb, "port status %08x", musb->port1_status);
376 		break;
377 	case SetPortFeature:
378 		if ((wIndex & 0xff) != 1)
379 			goto error;
380 
381 		switch (wValue) {
382 		case USB_PORT_FEAT_POWER:
383 			/* NOTE: this controller has a strange state machine
384 			 * that involves "requesting sessions" according to
385 			 * magic side effects from incompletely-described
386 			 * rules about startup...
387 			 *
388 			 * This call is what really starts the host mode; be
389 			 * very careful about side effects if you reorder any
390 			 * initialization logic, e.g. for OTG, or change any
391 			 * logic relating to VBUS power-up.
392 			 */
393 			if (!hcd->self.is_b_host && musb_has_gadget(musb))
394 				start_musb = true;
395 			break;
396 		case USB_PORT_FEAT_RESET:
397 			musb_port_reset(musb, true);
398 			break;
399 		case USB_PORT_FEAT_SUSPEND:
400 			musb_port_suspend(musb, true);
401 			break;
402 		case USB_PORT_FEAT_TEST:
403 			if (unlikely(is_host_active(musb)))
404 				goto error;
405 
406 			wIndex >>= 8;
407 			switch (wIndex) {
408 			case 1:
409 				pr_debug("TEST_J\n");
410 				temp = MUSB_TEST_J;
411 				break;
412 			case 2:
413 				pr_debug("TEST_K\n");
414 				temp = MUSB_TEST_K;
415 				break;
416 			case 3:
417 				pr_debug("TEST_SE0_NAK\n");
418 				temp = MUSB_TEST_SE0_NAK;
419 				break;
420 			case 4:
421 				pr_debug("TEST_PACKET\n");
422 				temp = MUSB_TEST_PACKET;
423 				musb_load_testpacket(musb);
424 				break;
425 			case 5:
426 				pr_debug("TEST_FORCE_ENABLE\n");
427 				temp = MUSB_TEST_FORCE_HOST
428 					| MUSB_TEST_FORCE_HS;
429 
430 				musb_writeb(musb->mregs, MUSB_DEVCTL,
431 						MUSB_DEVCTL_SESSION);
432 				break;
433 			case 6:
434 				pr_debug("TEST_FIFO_ACCESS\n");
435 				temp = MUSB_TEST_FIFO_ACCESS;
436 				break;
437 			default:
438 				goto error;
439 			}
440 			musb_writeb(musb->mregs, MUSB_TESTMODE, temp);
441 			break;
442 		default:
443 			goto error;
444 		}
445 		musb_dbg(musb, "set feature %d", wValue);
446 		musb->port1_status |= 1 << wValue;
447 		break;
448 
449 	default:
450 error:
451 		/* "protocol stall" on error */
452 		retval = -EPIPE;
453 	}
454 	spin_unlock_irqrestore(&musb->lock, flags);
455 
456 	if (start_musb)
457 		musb_start(musb);
458 
459 	return retval;
460 }
461