xref: /openbmc/linux/drivers/usb/host/uhci-hub.c (revision 9cfc5c90)
1 /*
2  * Universal Host Controller Interface driver for USB.
3  *
4  * Maintainer: Alan Stern <stern@rowland.harvard.edu>
5  *
6  * (C) Copyright 1999 Linus Torvalds
7  * (C) Copyright 1999-2002 Johannes Erdfelt, johannes@erdfelt.com
8  * (C) Copyright 1999 Randy Dunlap
9  * (C) Copyright 1999 Georg Acher, acher@in.tum.de
10  * (C) Copyright 1999 Deti Fliegl, deti@fliegl.de
11  * (C) Copyright 1999 Thomas Sailer, sailer@ife.ee.ethz.ch
12  * (C) Copyright 2004 Alan Stern, stern@rowland.harvard.edu
13  */
14 
15 static const __u8 root_hub_hub_des[] =
16 {
17 	0x09,			/*  __u8  bLength; */
18 	USB_DT_HUB,		/*  __u8  bDescriptorType; Hub-descriptor */
19 	0x02,			/*  __u8  bNbrPorts; */
20 	HUB_CHAR_NO_LPSM |	/* __u16  wHubCharacteristics; */
21 		HUB_CHAR_INDV_PORT_OCPM, /* (per-port OC, no power switching) */
22 	0x00,
23 	0x01,			/*  __u8  bPwrOn2pwrGood; 2ms */
24 	0x00,			/*  __u8  bHubContrCurrent; 0 mA */
25 	0x00,			/*  __u8  DeviceRemovable; *** 7 Ports max */
26 	0xff			/*  __u8  PortPwrCtrlMask; *** 7 ports max */
27 };
28 
29 #define	UHCI_RH_MAXCHILD	7
30 
31 /* must write as zeroes */
32 #define WZ_BITS		(USBPORTSC_RES2 | USBPORTSC_RES3 | USBPORTSC_RES4)
33 
34 /* status change bits:  nonzero writes will clear */
35 #define RWC_BITS	(USBPORTSC_OCC | USBPORTSC_PEC | USBPORTSC_CSC)
36 
37 /* suspend/resume bits: port suspended or port resuming */
38 #define SUSPEND_BITS	(USBPORTSC_SUSP | USBPORTSC_RD)
39 
40 /* A port that either is connected or has a changed-bit set will prevent
41  * us from AUTO_STOPPING.
42  */
43 static int any_ports_active(struct uhci_hcd *uhci)
44 {
45 	int port;
46 
47 	for (port = 0; port < uhci->rh_numports; ++port) {
48 		if ((uhci_readw(uhci, USBPORTSC1 + port * 2) &
49 				(USBPORTSC_CCS | RWC_BITS)) ||
50 				test_bit(port, &uhci->port_c_suspend))
51 			return 1;
52 	}
53 	return 0;
54 }
55 
56 static inline int get_hub_status_data(struct uhci_hcd *uhci, char *buf)
57 {
58 	int port;
59 	int mask = RWC_BITS;
60 
61 	/* Some boards (both VIA and Intel apparently) report bogus
62 	 * overcurrent indications, causing massive log spam unless
63 	 * we completely ignore them.  This doesn't seem to be a problem
64 	 * with the chipset so much as with the way it is connected on
65 	 * the motherboard; if the overcurrent input is left to float
66 	 * then it may constantly register false positives. */
67 	if (ignore_oc)
68 		mask &= ~USBPORTSC_OCC;
69 
70 	*buf = 0;
71 	for (port = 0; port < uhci->rh_numports; ++port) {
72 		if ((uhci_readw(uhci, USBPORTSC1 + port * 2) & mask) ||
73 				test_bit(port, &uhci->port_c_suspend))
74 			*buf |= (1 << (port + 1));
75 	}
76 	return !!*buf;
77 }
78 
79 #define CLR_RH_PORTSTAT(x) \
80 	status = uhci_readw(uhci, port_addr);	\
81 	status &= ~(RWC_BITS|WZ_BITS); \
82 	status &= ~(x); \
83 	status |= RWC_BITS & (x); \
84 	uhci_writew(uhci, status, port_addr)
85 
86 #define SET_RH_PORTSTAT(x) \
87 	status = uhci_readw(uhci, port_addr);	\
88 	status |= (x); \
89 	status &= ~(RWC_BITS|WZ_BITS); \
90 	uhci_writew(uhci, status, port_addr)
91 
92 /* UHCI controllers don't automatically stop resume signalling after 20 msec,
93  * so we have to poll and check timeouts in order to take care of it.
94  */
95 static void uhci_finish_suspend(struct uhci_hcd *uhci, int port,
96 		unsigned long port_addr)
97 {
98 	int status;
99 	int i;
100 
101 	if (uhci_readw(uhci, port_addr) & SUSPEND_BITS) {
102 		CLR_RH_PORTSTAT(SUSPEND_BITS);
103 		if (test_bit(port, &uhci->resuming_ports))
104 			set_bit(port, &uhci->port_c_suspend);
105 
106 		/* The controller won't actually turn off the RD bit until
107 		 * it has had a chance to send a low-speed EOP sequence,
108 		 * which is supposed to take 3 bit times (= 2 microseconds).
109 		 * Experiments show that some controllers take longer, so
110 		 * we'll poll for completion. */
111 		for (i = 0; i < 10; ++i) {
112 			if (!(uhci_readw(uhci, port_addr) & SUSPEND_BITS))
113 				break;
114 			udelay(1);
115 		}
116 	}
117 	clear_bit(port, &uhci->resuming_ports);
118 	usb_hcd_end_port_resume(&uhci_to_hcd(uhci)->self, port);
119 }
120 
121 /* Wait for the UHCI controller in HP's iLO2 server management chip.
122  * It can take up to 250 us to finish a reset and set the CSC bit.
123  */
124 static void wait_for_HP(struct uhci_hcd *uhci, unsigned long port_addr)
125 {
126 	int i;
127 
128 	for (i = 10; i < 250; i += 10) {
129 		if (uhci_readw(uhci, port_addr) & USBPORTSC_CSC)
130 			return;
131 		udelay(10);
132 	}
133 	/* Log a warning? */
134 }
135 
136 static void uhci_check_ports(struct uhci_hcd *uhci)
137 {
138 	unsigned int port;
139 	unsigned long port_addr;
140 	int status;
141 
142 	for (port = 0; port < uhci->rh_numports; ++port) {
143 		port_addr = USBPORTSC1 + 2 * port;
144 		status = uhci_readw(uhci, port_addr);
145 		if (unlikely(status & USBPORTSC_PR)) {
146 			if (time_after_eq(jiffies, uhci->ports_timeout)) {
147 				CLR_RH_PORTSTAT(USBPORTSC_PR);
148 				udelay(10);
149 
150 				/* HP's server management chip requires
151 				 * a longer delay. */
152 				if (uhci->wait_for_hp)
153 					wait_for_HP(uhci, port_addr);
154 
155 				/* If the port was enabled before, turning
156 				 * reset on caused a port enable change.
157 				 * Turning reset off causes a port connect
158 				 * status change.  Clear these changes. */
159 				CLR_RH_PORTSTAT(USBPORTSC_CSC | USBPORTSC_PEC);
160 				SET_RH_PORTSTAT(USBPORTSC_PE);
161 			}
162 		}
163 		if (unlikely(status & USBPORTSC_RD)) {
164 			if (!test_bit(port, &uhci->resuming_ports)) {
165 
166 				/* Port received a wakeup request */
167 				set_bit(port, &uhci->resuming_ports);
168 				uhci->ports_timeout = jiffies +
169 					msecs_to_jiffies(USB_RESUME_TIMEOUT);
170 				usb_hcd_start_port_resume(
171 						&uhci_to_hcd(uhci)->self, port);
172 
173 				/* Make sure we see the port again
174 				 * after the resuming period is over. */
175 				mod_timer(&uhci_to_hcd(uhci)->rh_timer,
176 						uhci->ports_timeout);
177 			} else if (time_after_eq(jiffies,
178 						uhci->ports_timeout)) {
179 				uhci_finish_suspend(uhci, port, port_addr);
180 			}
181 		}
182 	}
183 }
184 
185 static int uhci_hub_status_data(struct usb_hcd *hcd, char *buf)
186 {
187 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
188 	unsigned long flags;
189 	int status = 0;
190 
191 	spin_lock_irqsave(&uhci->lock, flags);
192 
193 	uhci_scan_schedule(uhci);
194 	if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
195 		goto done;
196 	uhci_check_ports(uhci);
197 
198 	status = get_hub_status_data(uhci, buf);
199 
200 	switch (uhci->rh_state) {
201 	    case UHCI_RH_SUSPENDED:
202 		/* if port change, ask to be resumed */
203 		if (status || uhci->resuming_ports) {
204 			status = 1;
205 			usb_hcd_resume_root_hub(hcd);
206 		}
207 		break;
208 
209 	    case UHCI_RH_AUTO_STOPPED:
210 		/* if port change, auto start */
211 		if (status)
212 			wakeup_rh(uhci);
213 		break;
214 
215 	    case UHCI_RH_RUNNING:
216 		/* are any devices attached? */
217 		if (!any_ports_active(uhci)) {
218 			uhci->rh_state = UHCI_RH_RUNNING_NODEVS;
219 			uhci->auto_stop_time = jiffies + HZ;
220 		}
221 		break;
222 
223 	    case UHCI_RH_RUNNING_NODEVS:
224 		/* auto-stop if nothing connected for 1 second */
225 		if (any_ports_active(uhci))
226 			uhci->rh_state = UHCI_RH_RUNNING;
227 		else if (time_after_eq(jiffies, uhci->auto_stop_time) &&
228 				!uhci->wait_for_hp)
229 			suspend_rh(uhci, UHCI_RH_AUTO_STOPPED);
230 		break;
231 
232 	    default:
233 		break;
234 	}
235 
236 done:
237 	spin_unlock_irqrestore(&uhci->lock, flags);
238 	return status;
239 }
240 
241 /* size of returned buffer is part of USB spec */
242 static int uhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
243 			u16 wIndex, char *buf, u16 wLength)
244 {
245 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
246 	int status, lstatus, retval = 0;
247 	unsigned int port = wIndex - 1;
248 	unsigned long port_addr = USBPORTSC1 + 2 * port;
249 	u16 wPortChange, wPortStatus;
250 	unsigned long flags;
251 
252 	if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
253 		return -ETIMEDOUT;
254 
255 	spin_lock_irqsave(&uhci->lock, flags);
256 	switch (typeReq) {
257 
258 	case GetHubStatus:
259 		*(__le32 *)buf = cpu_to_le32(0);
260 		retval = 4; /* hub power */
261 		break;
262 	case GetPortStatus:
263 		if (port >= uhci->rh_numports)
264 			goto err;
265 
266 		uhci_check_ports(uhci);
267 		status = uhci_readw(uhci, port_addr);
268 
269 		/* Intel controllers report the OverCurrent bit active on.
270 		 * VIA controllers report it active off, so we'll adjust the
271 		 * bit value.  (It's not standardized in the UHCI spec.)
272 		 */
273 		if (uhci->oc_low)
274 			status ^= USBPORTSC_OC;
275 
276 		/* UHCI doesn't support C_RESET (always false) */
277 		wPortChange = lstatus = 0;
278 		if (status & USBPORTSC_CSC)
279 			wPortChange |= USB_PORT_STAT_C_CONNECTION;
280 		if (status & USBPORTSC_PEC)
281 			wPortChange |= USB_PORT_STAT_C_ENABLE;
282 		if ((status & USBPORTSC_OCC) && !ignore_oc)
283 			wPortChange |= USB_PORT_STAT_C_OVERCURRENT;
284 
285 		if (test_bit(port, &uhci->port_c_suspend)) {
286 			wPortChange |= USB_PORT_STAT_C_SUSPEND;
287 			lstatus |= 1;
288 		}
289 		if (test_bit(port, &uhci->resuming_ports))
290 			lstatus |= 4;
291 
292 		/* UHCI has no power switching (always on) */
293 		wPortStatus = USB_PORT_STAT_POWER;
294 		if (status & USBPORTSC_CCS)
295 			wPortStatus |= USB_PORT_STAT_CONNECTION;
296 		if (status & USBPORTSC_PE) {
297 			wPortStatus |= USB_PORT_STAT_ENABLE;
298 			if (status & SUSPEND_BITS)
299 				wPortStatus |= USB_PORT_STAT_SUSPEND;
300 		}
301 		if (status & USBPORTSC_OC)
302 			wPortStatus |= USB_PORT_STAT_OVERCURRENT;
303 		if (status & USBPORTSC_PR)
304 			wPortStatus |= USB_PORT_STAT_RESET;
305 		if (status & USBPORTSC_LSDA)
306 			wPortStatus |= USB_PORT_STAT_LOW_SPEED;
307 
308 		if (wPortChange)
309 			dev_dbg(uhci_dev(uhci), "port %d portsc %04x,%02x\n",
310 					wIndex, status, lstatus);
311 
312 		*(__le16 *)buf = cpu_to_le16(wPortStatus);
313 		*(__le16 *)(buf + 2) = cpu_to_le16(wPortChange);
314 		retval = 4;
315 		break;
316 	case SetHubFeature:		/* We don't implement these */
317 	case ClearHubFeature:
318 		switch (wValue) {
319 		case C_HUB_OVER_CURRENT:
320 		case C_HUB_LOCAL_POWER:
321 			break;
322 		default:
323 			goto err;
324 		}
325 		break;
326 	case SetPortFeature:
327 		if (port >= uhci->rh_numports)
328 			goto err;
329 
330 		switch (wValue) {
331 		case USB_PORT_FEAT_SUSPEND:
332 			SET_RH_PORTSTAT(USBPORTSC_SUSP);
333 			break;
334 		case USB_PORT_FEAT_RESET:
335 			SET_RH_PORTSTAT(USBPORTSC_PR);
336 
337 			/* Reset terminates Resume signalling */
338 			uhci_finish_suspend(uhci, port, port_addr);
339 
340 			/* USB v2.0 7.1.7.5 */
341 			uhci->ports_timeout = jiffies +
342 				msecs_to_jiffies(USB_RESUME_TIMEOUT);
343 			break;
344 		case USB_PORT_FEAT_POWER:
345 			/* UHCI has no power switching */
346 			break;
347 		default:
348 			goto err;
349 		}
350 		break;
351 	case ClearPortFeature:
352 		if (port >= uhci->rh_numports)
353 			goto err;
354 
355 		switch (wValue) {
356 		case USB_PORT_FEAT_ENABLE:
357 			CLR_RH_PORTSTAT(USBPORTSC_PE);
358 
359 			/* Disable terminates Resume signalling */
360 			uhci_finish_suspend(uhci, port, port_addr);
361 			break;
362 		case USB_PORT_FEAT_C_ENABLE:
363 			CLR_RH_PORTSTAT(USBPORTSC_PEC);
364 			break;
365 		case USB_PORT_FEAT_SUSPEND:
366 			if (!(uhci_readw(uhci, port_addr) & USBPORTSC_SUSP)) {
367 
368 				/* Make certain the port isn't suspended */
369 				uhci_finish_suspend(uhci, port, port_addr);
370 			} else if (!test_and_set_bit(port,
371 						&uhci->resuming_ports)) {
372 				SET_RH_PORTSTAT(USBPORTSC_RD);
373 
374 				/* The controller won't allow RD to be set
375 				 * if the port is disabled.  When this happens
376 				 * just skip the Resume signalling.
377 				 */
378 				if (!(uhci_readw(uhci, port_addr) &
379 						USBPORTSC_RD))
380 					uhci_finish_suspend(uhci, port,
381 							port_addr);
382 				else
383 					/* USB v2.0 7.1.7.7 */
384 					uhci->ports_timeout = jiffies +
385 						msecs_to_jiffies(20);
386 			}
387 			break;
388 		case USB_PORT_FEAT_C_SUSPEND:
389 			clear_bit(port, &uhci->port_c_suspend);
390 			break;
391 		case USB_PORT_FEAT_POWER:
392 			/* UHCI has no power switching */
393 			goto err;
394 		case USB_PORT_FEAT_C_CONNECTION:
395 			CLR_RH_PORTSTAT(USBPORTSC_CSC);
396 			break;
397 		case USB_PORT_FEAT_C_OVER_CURRENT:
398 			CLR_RH_PORTSTAT(USBPORTSC_OCC);
399 			break;
400 		case USB_PORT_FEAT_C_RESET:
401 			/* this driver won't report these */
402 			break;
403 		default:
404 			goto err;
405 		}
406 		break;
407 	case GetHubDescriptor:
408 		retval = min_t(unsigned int, sizeof(root_hub_hub_des), wLength);
409 		memcpy(buf, root_hub_hub_des, retval);
410 		if (retval > 2)
411 			buf[2] = uhci->rh_numports;
412 		break;
413 	default:
414 err:
415 		retval = -EPIPE;
416 	}
417 	spin_unlock_irqrestore(&uhci->lock, flags);
418 
419 	return retval;
420 }
421