xref: /openbmc/linux/drivers/usb/musb/musb_virthub.c (revision 31b90347)
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/init.h>
40 #include <linux/time.h>
41 #include <linux/timer.h>
42 
43 #include <asm/unaligned.h>
44 
45 #include "musb_core.h"
46 
47 static void musb_port_suspend(struct musb *musb, bool do_suspend)
48 {
49 	struct usb_otg	*otg = musb->xceiv->otg;
50 	u8		power;
51 	void __iomem	*mbase = musb->mregs;
52 
53 	if (!is_host_active(musb))
54 		return;
55 
56 	/* NOTE:  this doesn't necessarily put PHY into low power mode,
57 	 * turning off its clock; that's a function of PHY integration and
58 	 * MUSB_POWER_ENSUSPEND.  PHY may need a clock (sigh) to detect
59 	 * SE0 changing to connect (J) or wakeup (K) states.
60 	 */
61 	power = musb_readb(mbase, MUSB_POWER);
62 	if (do_suspend) {
63 		int retries = 10000;
64 
65 		power &= ~MUSB_POWER_RESUME;
66 		power |= MUSB_POWER_SUSPENDM;
67 		musb_writeb(mbase, MUSB_POWER, power);
68 
69 		/* Needed for OPT A tests */
70 		power = musb_readb(mbase, MUSB_POWER);
71 		while (power & MUSB_POWER_SUSPENDM) {
72 			power = musb_readb(mbase, MUSB_POWER);
73 			if (retries-- < 1)
74 				break;
75 		}
76 
77 		dev_dbg(musb->controller, "Root port suspended, power %02x\n", power);
78 
79 		musb->port1_status |= USB_PORT_STAT_SUSPEND;
80 		switch (musb->xceiv->state) {
81 		case OTG_STATE_A_HOST:
82 			musb->xceiv->state = OTG_STATE_A_SUSPEND;
83 			musb->is_active = otg->host->b_hnp_enable;
84 			if (musb->is_active)
85 				mod_timer(&musb->otg_timer, jiffies
86 					+ msecs_to_jiffies(
87 						OTG_TIME_A_AIDL_BDIS));
88 			musb_platform_try_idle(musb, 0);
89 			break;
90 		case OTG_STATE_B_HOST:
91 			musb->xceiv->state = OTG_STATE_B_WAIT_ACON;
92 			musb->is_active = otg->host->b_hnp_enable;
93 			musb_platform_try_idle(musb, 0);
94 			break;
95 		default:
96 			dev_dbg(musb->controller, "bogus rh suspend? %s\n",
97 				usb_otg_state_string(musb->xceiv->state));
98 		}
99 	} else if (power & MUSB_POWER_SUSPENDM) {
100 		power &= ~MUSB_POWER_SUSPENDM;
101 		power |= MUSB_POWER_RESUME;
102 		musb_writeb(mbase, MUSB_POWER, power);
103 
104 		dev_dbg(musb->controller, "Root port resuming, power %02x\n", power);
105 
106 		/* later, GetPortStatus will stop RESUME signaling */
107 		musb->port1_status |= MUSB_PORT_STAT_RESUME;
108 		musb->rh_timer = jiffies + msecs_to_jiffies(20);
109 	}
110 }
111 
112 static void musb_port_reset(struct musb *musb, bool do_reset)
113 {
114 	u8		power;
115 	void __iomem	*mbase = musb->mregs;
116 
117 	if (musb->xceiv->state == OTG_STATE_B_IDLE) {
118 		dev_dbg(musb->controller, "HNP: Returning from HNP; no hub reset from b_idle\n");
119 		musb->port1_status &= ~USB_PORT_STAT_RESET;
120 		return;
121 	}
122 
123 	if (!is_host_active(musb))
124 		return;
125 
126 	/* NOTE:  caller guarantees it will turn off the reset when
127 	 * the appropriate amount of time has passed
128 	 */
129 	power = musb_readb(mbase, MUSB_POWER);
130 	if (do_reset) {
131 
132 		/*
133 		 * If RESUME is set, we must make sure it stays minimum 20 ms.
134 		 * Then we must clear RESUME and wait a bit to let musb start
135 		 * generating SOFs. If we don't do this, OPT HS A 6.8 tests
136 		 * fail with "Error! Did not receive an SOF before suspend
137 		 * detected".
138 		 */
139 		if (power &  MUSB_POWER_RESUME) {
140 			while (time_before(jiffies, musb->rh_timer))
141 				msleep(1);
142 			musb_writeb(mbase, MUSB_POWER,
143 				power & ~MUSB_POWER_RESUME);
144 			msleep(1);
145 		}
146 
147 		power &= 0xf0;
148 		musb_writeb(mbase, MUSB_POWER,
149 				power | MUSB_POWER_RESET);
150 
151 		musb->port1_status |= USB_PORT_STAT_RESET;
152 		musb->port1_status &= ~USB_PORT_STAT_ENABLE;
153 		musb->rh_timer = jiffies + msecs_to_jiffies(50);
154 	} else {
155 		dev_dbg(musb->controller, "root port reset stopped\n");
156 		musb_writeb(mbase, MUSB_POWER,
157 				power & ~MUSB_POWER_RESET);
158 
159 		power = musb_readb(mbase, MUSB_POWER);
160 		if (power & MUSB_POWER_HSMODE) {
161 			dev_dbg(musb->controller, "high-speed device connected\n");
162 			musb->port1_status |= USB_PORT_STAT_HIGH_SPEED;
163 		}
164 
165 		musb->port1_status &= ~USB_PORT_STAT_RESET;
166 		musb->port1_status |= USB_PORT_STAT_ENABLE
167 					| (USB_PORT_STAT_C_RESET << 16)
168 					| (USB_PORT_STAT_C_ENABLE << 16);
169 		usb_hcd_poll_rh_status(musb->hcd);
170 
171 		musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
172 	}
173 }
174 
175 void musb_root_disconnect(struct musb *musb)
176 {
177 	struct usb_otg	*otg = musb->xceiv->otg;
178 
179 	musb->port1_status = USB_PORT_STAT_POWER
180 			| (USB_PORT_STAT_C_CONNECTION << 16);
181 
182 	usb_hcd_poll_rh_status(musb->hcd);
183 	musb->is_active = 0;
184 
185 	switch (musb->xceiv->state) {
186 	case OTG_STATE_A_SUSPEND:
187 		if (otg->host->b_hnp_enable) {
188 			musb->xceiv->state = OTG_STATE_A_PERIPHERAL;
189 			musb->g.is_a_peripheral = 1;
190 			break;
191 		}
192 		/* FALLTHROUGH */
193 	case OTG_STATE_A_HOST:
194 		musb->xceiv->state = OTG_STATE_A_WAIT_BCON;
195 		musb->is_active = 0;
196 		break;
197 	case OTG_STATE_A_WAIT_VFALL:
198 		musb->xceiv->state = OTG_STATE_B_IDLE;
199 		break;
200 	default:
201 		dev_dbg(musb->controller, "host disconnect (%s)\n",
202 			usb_otg_state_string(musb->xceiv->state));
203 	}
204 }
205 
206 
207 /*---------------------------------------------------------------------*/
208 
209 /* Caller may or may not hold musb->lock */
210 int musb_hub_status_data(struct usb_hcd *hcd, char *buf)
211 {
212 	struct musb	*musb = hcd_to_musb(hcd);
213 	int		retval = 0;
214 
215 	/* called in_irq() via usb_hcd_poll_rh_status() */
216 	if (musb->port1_status & 0xffff0000) {
217 		*buf = 0x02;
218 		retval = 1;
219 	}
220 	return retval;
221 }
222 
223 static int musb_has_gadget(struct musb *musb)
224 {
225 	/*
226 	 * In host-only mode we start a connection right away. In OTG mode
227 	 * we have to wait until we loaded a gadget. We don't really need a
228 	 * gadget if we operate as a host but we should not start a session
229 	 * as a device without a gadget or else we explode.
230 	 */
231 #ifdef CONFIG_USB_MUSB_HOST
232 	return 1;
233 #else
234 	if (musb->port_mode == MUSB_PORT_MODE_HOST)
235 		return 1;
236 	return musb->g.dev.driver != NULL;
237 #endif
238 }
239 
240 int musb_hub_control(
241 	struct usb_hcd	*hcd,
242 	u16		typeReq,
243 	u16		wValue,
244 	u16		wIndex,
245 	char		*buf,
246 	u16		wLength)
247 {
248 	struct musb	*musb = hcd_to_musb(hcd);
249 	u32		temp;
250 	int		retval = 0;
251 	unsigned long	flags;
252 
253 	spin_lock_irqsave(&musb->lock, flags);
254 
255 	if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) {
256 		spin_unlock_irqrestore(&musb->lock, flags);
257 		return -ESHUTDOWN;
258 	}
259 
260 	/* hub features:  always zero, setting is a NOP
261 	 * port features: reported, sometimes updated when host is active
262 	 * no indicators
263 	 */
264 	switch (typeReq) {
265 	case ClearHubFeature:
266 	case SetHubFeature:
267 		switch (wValue) {
268 		case C_HUB_OVER_CURRENT:
269 		case C_HUB_LOCAL_POWER:
270 			break;
271 		default:
272 			goto error;
273 		}
274 		break;
275 	case ClearPortFeature:
276 		if ((wIndex & 0xff) != 1)
277 			goto error;
278 
279 		switch (wValue) {
280 		case USB_PORT_FEAT_ENABLE:
281 			break;
282 		case USB_PORT_FEAT_SUSPEND:
283 			musb_port_suspend(musb, false);
284 			break;
285 		case USB_PORT_FEAT_POWER:
286 			if (!hcd->self.is_b_host)
287 				musb_platform_set_vbus(musb, 0);
288 			break;
289 		case USB_PORT_FEAT_C_CONNECTION:
290 		case USB_PORT_FEAT_C_ENABLE:
291 		case USB_PORT_FEAT_C_OVER_CURRENT:
292 		case USB_PORT_FEAT_C_RESET:
293 		case USB_PORT_FEAT_C_SUSPEND:
294 			break;
295 		default:
296 			goto error;
297 		}
298 		dev_dbg(musb->controller, "clear feature %d\n", wValue);
299 		musb->port1_status &= ~(1 << wValue);
300 		break;
301 	case GetHubDescriptor:
302 		{
303 		struct usb_hub_descriptor *desc = (void *)buf;
304 
305 		desc->bDescLength = 9;
306 		desc->bDescriptorType = 0x29;
307 		desc->bNbrPorts = 1;
308 		desc->wHubCharacteristics = cpu_to_le16(
309 				  0x0001	/* per-port power switching */
310 				| 0x0010	/* no overcurrent reporting */
311 				);
312 		desc->bPwrOn2PwrGood = 5;	/* msec/2 */
313 		desc->bHubContrCurrent = 0;
314 
315 		/* workaround bogus struct definition */
316 		desc->u.hs.DeviceRemovable[0] = 0x02;	/* port 1 */
317 		desc->u.hs.DeviceRemovable[1] = 0xff;
318 		}
319 		break;
320 	case GetHubStatus:
321 		temp = 0;
322 		*(__le32 *) buf = cpu_to_le32(temp);
323 		break;
324 	case GetPortStatus:
325 		if (wIndex != 1)
326 			goto error;
327 
328 		/* finish RESET signaling? */
329 		if ((musb->port1_status & USB_PORT_STAT_RESET)
330 				&& time_after_eq(jiffies, musb->rh_timer))
331 			musb_port_reset(musb, false);
332 
333 		/* finish RESUME signaling? */
334 		if ((musb->port1_status & MUSB_PORT_STAT_RESUME)
335 				&& time_after_eq(jiffies, musb->rh_timer)) {
336 			u8		power;
337 
338 			power = musb_readb(musb->mregs, MUSB_POWER);
339 			power &= ~MUSB_POWER_RESUME;
340 			dev_dbg(musb->controller, "root port resume stopped, power %02x\n",
341 					power);
342 			musb_writeb(musb->mregs, MUSB_POWER, power);
343 
344 			/* ISSUE:  DaVinci (RTL 1.300) disconnects after
345 			 * resume of high speed peripherals (but not full
346 			 * speed ones).
347 			 */
348 
349 			musb->is_active = 1;
350 			musb->port1_status &= ~(USB_PORT_STAT_SUSPEND
351 					| MUSB_PORT_STAT_RESUME);
352 			musb->port1_status |= USB_PORT_STAT_C_SUSPEND << 16;
353 			usb_hcd_poll_rh_status(musb->hcd);
354 			/* NOTE: it might really be A_WAIT_BCON ... */
355 			musb->xceiv->state = OTG_STATE_A_HOST;
356 		}
357 
358 		put_unaligned(cpu_to_le32(musb->port1_status
359 					& ~MUSB_PORT_STAT_RESUME),
360 				(__le32 *) buf);
361 
362 		/* port change status is more interesting */
363 		dev_dbg(musb->controller, "port status %08x\n",
364 				musb->port1_status);
365 		break;
366 	case SetPortFeature:
367 		if ((wIndex & 0xff) != 1)
368 			goto error;
369 
370 		switch (wValue) {
371 		case USB_PORT_FEAT_POWER:
372 			/* NOTE: this controller has a strange state machine
373 			 * that involves "requesting sessions" according to
374 			 * magic side effects from incompletely-described
375 			 * rules about startup...
376 			 *
377 			 * This call is what really starts the host mode; be
378 			 * very careful about side effects if you reorder any
379 			 * initialization logic, e.g. for OTG, or change any
380 			 * logic relating to VBUS power-up.
381 			 */
382 			if (!hcd->self.is_b_host && musb_has_gadget(musb))
383 				musb_start(musb);
384 			break;
385 		case USB_PORT_FEAT_RESET:
386 			musb_port_reset(musb, true);
387 			break;
388 		case USB_PORT_FEAT_SUSPEND:
389 			musb_port_suspend(musb, true);
390 			break;
391 		case USB_PORT_FEAT_TEST:
392 			if (unlikely(is_host_active(musb)))
393 				goto error;
394 
395 			wIndex >>= 8;
396 			switch (wIndex) {
397 			case 1:
398 				pr_debug("TEST_J\n");
399 				temp = MUSB_TEST_J;
400 				break;
401 			case 2:
402 				pr_debug("TEST_K\n");
403 				temp = MUSB_TEST_K;
404 				break;
405 			case 3:
406 				pr_debug("TEST_SE0_NAK\n");
407 				temp = MUSB_TEST_SE0_NAK;
408 				break;
409 			case 4:
410 				pr_debug("TEST_PACKET\n");
411 				temp = MUSB_TEST_PACKET;
412 				musb_load_testpacket(musb);
413 				break;
414 			case 5:
415 				pr_debug("TEST_FORCE_ENABLE\n");
416 				temp = MUSB_TEST_FORCE_HOST
417 					| MUSB_TEST_FORCE_HS;
418 
419 				musb_writeb(musb->mregs, MUSB_DEVCTL,
420 						MUSB_DEVCTL_SESSION);
421 				break;
422 			case 6:
423 				pr_debug("TEST_FIFO_ACCESS\n");
424 				temp = MUSB_TEST_FIFO_ACCESS;
425 				break;
426 			default:
427 				goto error;
428 			}
429 			musb_writeb(musb->mregs, MUSB_TESTMODE, temp);
430 			break;
431 		default:
432 			goto error;
433 		}
434 		dev_dbg(musb->controller, "set feature %d\n", wValue);
435 		musb->port1_status |= 1 << wValue;
436 		break;
437 
438 	default:
439 error:
440 		/* "protocol stall" on error */
441 		retval = -EPIPE;
442 	}
443 	spin_unlock_irqrestore(&musb->lock, flags);
444 	return retval;
445 }
446