xref: /openbmc/linux/drivers/usb/host/uhci-hub.c (revision 275876e2)
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 	0x29,			/*  __u8  bDescriptorType; Hub-descriptor */
19 	0x02,			/*  __u8  bNbrPorts; */
20 	0x0a,			/* __u16  wHubCharacteristics; */
21 	0x00,			/*   (per-port OC, no power switching) */
22 	0x01,			/*  __u8  bPwrOn2pwrGood; 2ms */
23 	0x00,			/*  __u8  bHubContrCurrent; 0 mA */
24 	0x00,			/*  __u8  DeviceRemovable; *** 7 Ports max */
25 	0xff			/*  __u8  PortPwrCtrlMask; *** 7 ports max */
26 };
27 
28 #define	UHCI_RH_MAXCHILD	7
29 
30 /* must write as zeroes */
31 #define WZ_BITS		(USBPORTSC_RES2 | USBPORTSC_RES3 | USBPORTSC_RES4)
32 
33 /* status change bits:  nonzero writes will clear */
34 #define RWC_BITS	(USBPORTSC_OCC | USBPORTSC_PEC | USBPORTSC_CSC)
35 
36 /* suspend/resume bits: port suspended or port resuming */
37 #define SUSPEND_BITS	(USBPORTSC_SUSP | USBPORTSC_RD)
38 
39 /* A port that either is connected or has a changed-bit set will prevent
40  * us from AUTO_STOPPING.
41  */
42 static int any_ports_active(struct uhci_hcd *uhci)
43 {
44 	int port;
45 
46 	for (port = 0; port < uhci->rh_numports; ++port) {
47 		if ((uhci_readw(uhci, USBPORTSC1 + port * 2) &
48 				(USBPORTSC_CCS | RWC_BITS)) ||
49 				test_bit(port, &uhci->port_c_suspend))
50 			return 1;
51 	}
52 	return 0;
53 }
54 
55 static inline int get_hub_status_data(struct uhci_hcd *uhci, char *buf)
56 {
57 	int port;
58 	int mask = RWC_BITS;
59 
60 	/* Some boards (both VIA and Intel apparently) report bogus
61 	 * overcurrent indications, causing massive log spam unless
62 	 * we completely ignore them.  This doesn't seem to be a problem
63 	 * with the chipset so much as with the way it is connected on
64 	 * the motherboard; if the overcurrent input is left to float
65 	 * then it may constantly register false positives. */
66 	if (ignore_oc)
67 		mask &= ~USBPORTSC_OCC;
68 
69 	*buf = 0;
70 	for (port = 0; port < uhci->rh_numports; ++port) {
71 		if ((uhci_readw(uhci, USBPORTSC1 + port * 2) & mask) ||
72 				test_bit(port, &uhci->port_c_suspend))
73 			*buf |= (1 << (port + 1));
74 	}
75 	return !!*buf;
76 }
77 
78 #define CLR_RH_PORTSTAT(x) \
79 	status = uhci_readw(uhci, port_addr);	\
80 	status &= ~(RWC_BITS|WZ_BITS); \
81 	status &= ~(x); \
82 	status |= RWC_BITS & (x); \
83 	uhci_writew(uhci, status, port_addr)
84 
85 #define SET_RH_PORTSTAT(x) \
86 	status = uhci_readw(uhci, port_addr);	\
87 	status |= (x); \
88 	status &= ~(RWC_BITS|WZ_BITS); \
89 	uhci_writew(uhci, status, port_addr)
90 
91 /* UHCI controllers don't automatically stop resume signalling after 20 msec,
92  * so we have to poll and check timeouts in order to take care of it.
93  */
94 static void uhci_finish_suspend(struct uhci_hcd *uhci, int port,
95 		unsigned long port_addr)
96 {
97 	int status;
98 	int i;
99 
100 	if (uhci_readw(uhci, port_addr) & SUSPEND_BITS) {
101 		CLR_RH_PORTSTAT(SUSPEND_BITS);
102 		if (test_bit(port, &uhci->resuming_ports))
103 			set_bit(port, &uhci->port_c_suspend);
104 
105 		/* The controller won't actually turn off the RD bit until
106 		 * it has had a chance to send a low-speed EOP sequence,
107 		 * which is supposed to take 3 bit times (= 2 microseconds).
108 		 * Experiments show that some controllers take longer, so
109 		 * we'll poll for completion. */
110 		for (i = 0; i < 10; ++i) {
111 			if (!(uhci_readw(uhci, port_addr) & SUSPEND_BITS))
112 				break;
113 			udelay(1);
114 		}
115 	}
116 	clear_bit(port, &uhci->resuming_ports);
117 	usb_hcd_end_port_resume(&uhci_to_hcd(uhci)->self, port);
118 }
119 
120 /* Wait for the UHCI controller in HP's iLO2 server management chip.
121  * It can take up to 250 us to finish a reset and set the CSC bit.
122  */
123 static void wait_for_HP(struct uhci_hcd *uhci, unsigned long port_addr)
124 {
125 	int i;
126 
127 	for (i = 10; i < 250; i += 10) {
128 		if (uhci_readw(uhci, port_addr) & USBPORTSC_CSC)
129 			return;
130 		udelay(10);
131 	}
132 	/* Log a warning? */
133 }
134 
135 static void uhci_check_ports(struct uhci_hcd *uhci)
136 {
137 	unsigned int port;
138 	unsigned long port_addr;
139 	int status;
140 
141 	for (port = 0; port < uhci->rh_numports; ++port) {
142 		port_addr = USBPORTSC1 + 2 * port;
143 		status = uhci_readw(uhci, port_addr);
144 		if (unlikely(status & USBPORTSC_PR)) {
145 			if (time_after_eq(jiffies, uhci->ports_timeout)) {
146 				CLR_RH_PORTSTAT(USBPORTSC_PR);
147 				udelay(10);
148 
149 				/* HP's server management chip requires
150 				 * a longer delay. */
151 				if (uhci->wait_for_hp)
152 					wait_for_HP(uhci, port_addr);
153 
154 				/* If the port was enabled before, turning
155 				 * reset on caused a port enable change.
156 				 * Turning reset off causes a port connect
157 				 * status change.  Clear these changes. */
158 				CLR_RH_PORTSTAT(USBPORTSC_CSC | USBPORTSC_PEC);
159 				SET_RH_PORTSTAT(USBPORTSC_PE);
160 			}
161 		}
162 		if (unlikely(status & USBPORTSC_RD)) {
163 			if (!test_bit(port, &uhci->resuming_ports)) {
164 
165 				/* Port received a wakeup request */
166 				set_bit(port, &uhci->resuming_ports);
167 				uhci->ports_timeout = jiffies +
168 						msecs_to_jiffies(25);
169 				usb_hcd_start_port_resume(
170 						&uhci_to_hcd(uhci)->self, port);
171 
172 				/* Make sure we see the port again
173 				 * after the resuming period is over. */
174 				mod_timer(&uhci_to_hcd(uhci)->rh_timer,
175 						uhci->ports_timeout);
176 			} else if (time_after_eq(jiffies,
177 						uhci->ports_timeout)) {
178 				uhci_finish_suspend(uhci, port, port_addr);
179 			}
180 		}
181 	}
182 }
183 
184 static int uhci_hub_status_data(struct usb_hcd *hcd, char *buf)
185 {
186 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
187 	unsigned long flags;
188 	int status = 0;
189 
190 	spin_lock_irqsave(&uhci->lock, flags);
191 
192 	uhci_scan_schedule(uhci);
193 	if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
194 		goto done;
195 	uhci_check_ports(uhci);
196 
197 	status = get_hub_status_data(uhci, buf);
198 
199 	switch (uhci->rh_state) {
200 	    case UHCI_RH_SUSPENDED:
201 		/* if port change, ask to be resumed */
202 		if (status || uhci->resuming_ports) {
203 			status = 1;
204 			usb_hcd_resume_root_hub(hcd);
205 		}
206 		break;
207 
208 	    case UHCI_RH_AUTO_STOPPED:
209 		/* if port change, auto start */
210 		if (status)
211 			wakeup_rh(uhci);
212 		break;
213 
214 	    case UHCI_RH_RUNNING:
215 		/* are any devices attached? */
216 		if (!any_ports_active(uhci)) {
217 			uhci->rh_state = UHCI_RH_RUNNING_NODEVS;
218 			uhci->auto_stop_time = jiffies + HZ;
219 		}
220 		break;
221 
222 	    case UHCI_RH_RUNNING_NODEVS:
223 		/* auto-stop if nothing connected for 1 second */
224 		if (any_ports_active(uhci))
225 			uhci->rh_state = UHCI_RH_RUNNING;
226 		else if (time_after_eq(jiffies, uhci->auto_stop_time) &&
227 				!uhci->wait_for_hp)
228 			suspend_rh(uhci, UHCI_RH_AUTO_STOPPED);
229 		break;
230 
231 	    default:
232 		break;
233 	}
234 
235 done:
236 	spin_unlock_irqrestore(&uhci->lock, flags);
237 	return status;
238 }
239 
240 /* size of returned buffer is part of USB spec */
241 static int uhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
242 			u16 wIndex, char *buf, u16 wLength)
243 {
244 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
245 	int status, lstatus, retval = 0;
246 	unsigned int port = wIndex - 1;
247 	unsigned long port_addr = USBPORTSC1 + 2 * port;
248 	u16 wPortChange, wPortStatus;
249 	unsigned long flags;
250 
251 	if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
252 		return -ETIMEDOUT;
253 
254 	spin_lock_irqsave(&uhci->lock, flags);
255 	switch (typeReq) {
256 
257 	case GetHubStatus:
258 		*(__le32 *)buf = cpu_to_le32(0);
259 		retval = 4; /* hub power */
260 		break;
261 	case GetPortStatus:
262 		if (port >= uhci->rh_numports)
263 			goto err;
264 
265 		uhci_check_ports(uhci);
266 		status = uhci_readw(uhci, port_addr);
267 
268 		/* Intel controllers report the OverCurrent bit active on.
269 		 * VIA controllers report it active off, so we'll adjust the
270 		 * bit value.  (It's not standardized in the UHCI spec.)
271 		 */
272 		if (uhci->oc_low)
273 			status ^= USBPORTSC_OC;
274 
275 		/* UHCI doesn't support C_RESET (always false) */
276 		wPortChange = lstatus = 0;
277 		if (status & USBPORTSC_CSC)
278 			wPortChange |= USB_PORT_STAT_C_CONNECTION;
279 		if (status & USBPORTSC_PEC)
280 			wPortChange |= USB_PORT_STAT_C_ENABLE;
281 		if ((status & USBPORTSC_OCC) && !ignore_oc)
282 			wPortChange |= USB_PORT_STAT_C_OVERCURRENT;
283 
284 		if (test_bit(port, &uhci->port_c_suspend)) {
285 			wPortChange |= USB_PORT_STAT_C_SUSPEND;
286 			lstatus |= 1;
287 		}
288 		if (test_bit(port, &uhci->resuming_ports))
289 			lstatus |= 4;
290 
291 		/* UHCI has no power switching (always on) */
292 		wPortStatus = USB_PORT_STAT_POWER;
293 		if (status & USBPORTSC_CCS)
294 			wPortStatus |= USB_PORT_STAT_CONNECTION;
295 		if (status & USBPORTSC_PE) {
296 			wPortStatus |= USB_PORT_STAT_ENABLE;
297 			if (status & SUSPEND_BITS)
298 				wPortStatus |= USB_PORT_STAT_SUSPEND;
299 		}
300 		if (status & USBPORTSC_OC)
301 			wPortStatus |= USB_PORT_STAT_OVERCURRENT;
302 		if (status & USBPORTSC_PR)
303 			wPortStatus |= USB_PORT_STAT_RESET;
304 		if (status & USBPORTSC_LSDA)
305 			wPortStatus |= USB_PORT_STAT_LOW_SPEED;
306 
307 		if (wPortChange)
308 			dev_dbg(uhci_dev(uhci), "port %d portsc %04x,%02x\n",
309 					wIndex, status, lstatus);
310 
311 		*(__le16 *)buf = cpu_to_le16(wPortStatus);
312 		*(__le16 *)(buf + 2) = cpu_to_le16(wPortChange);
313 		retval = 4;
314 		break;
315 	case SetHubFeature:		/* We don't implement these */
316 	case ClearHubFeature:
317 		switch (wValue) {
318 		case C_HUB_OVER_CURRENT:
319 		case C_HUB_LOCAL_POWER:
320 			break;
321 		default:
322 			goto err;
323 		}
324 		break;
325 	case SetPortFeature:
326 		if (port >= uhci->rh_numports)
327 			goto err;
328 
329 		switch (wValue) {
330 		case USB_PORT_FEAT_SUSPEND:
331 			SET_RH_PORTSTAT(USBPORTSC_SUSP);
332 			break;
333 		case USB_PORT_FEAT_RESET:
334 			SET_RH_PORTSTAT(USBPORTSC_PR);
335 
336 			/* Reset terminates Resume signalling */
337 			uhci_finish_suspend(uhci, port, port_addr);
338 
339 			/* USB v2.0 7.1.7.5 */
340 			uhci->ports_timeout = jiffies + msecs_to_jiffies(50);
341 			break;
342 		case USB_PORT_FEAT_POWER:
343 			/* UHCI has no power switching */
344 			break;
345 		default:
346 			goto err;
347 		}
348 		break;
349 	case ClearPortFeature:
350 		if (port >= uhci->rh_numports)
351 			goto err;
352 
353 		switch (wValue) {
354 		case USB_PORT_FEAT_ENABLE:
355 			CLR_RH_PORTSTAT(USBPORTSC_PE);
356 
357 			/* Disable terminates Resume signalling */
358 			uhci_finish_suspend(uhci, port, port_addr);
359 			break;
360 		case USB_PORT_FEAT_C_ENABLE:
361 			CLR_RH_PORTSTAT(USBPORTSC_PEC);
362 			break;
363 		case USB_PORT_FEAT_SUSPEND:
364 			if (!(uhci_readw(uhci, port_addr) & USBPORTSC_SUSP)) {
365 
366 				/* Make certain the port isn't suspended */
367 				uhci_finish_suspend(uhci, port, port_addr);
368 			} else if (!test_and_set_bit(port,
369 						&uhci->resuming_ports)) {
370 				SET_RH_PORTSTAT(USBPORTSC_RD);
371 
372 				/* The controller won't allow RD to be set
373 				 * if the port is disabled.  When this happens
374 				 * just skip the Resume signalling.
375 				 */
376 				if (!(uhci_readw(uhci, port_addr) &
377 						USBPORTSC_RD))
378 					uhci_finish_suspend(uhci, port,
379 							port_addr);
380 				else
381 					/* USB v2.0 7.1.7.7 */
382 					uhci->ports_timeout = jiffies +
383 						msecs_to_jiffies(20);
384 			}
385 			break;
386 		case USB_PORT_FEAT_C_SUSPEND:
387 			clear_bit(port, &uhci->port_c_suspend);
388 			break;
389 		case USB_PORT_FEAT_POWER:
390 			/* UHCI has no power switching */
391 			goto err;
392 		case USB_PORT_FEAT_C_CONNECTION:
393 			CLR_RH_PORTSTAT(USBPORTSC_CSC);
394 			break;
395 		case USB_PORT_FEAT_C_OVER_CURRENT:
396 			CLR_RH_PORTSTAT(USBPORTSC_OCC);
397 			break;
398 		case USB_PORT_FEAT_C_RESET:
399 			/* this driver won't report these */
400 			break;
401 		default:
402 			goto err;
403 		}
404 		break;
405 	case GetHubDescriptor:
406 		retval = min_t(unsigned int, sizeof(root_hub_hub_des), wLength);
407 		memcpy(buf, root_hub_hub_des, retval);
408 		if (retval > 2)
409 			buf[2] = uhci->rh_numports;
410 		break;
411 	default:
412 err:
413 		retval = -EPIPE;
414 	}
415 	spin_unlock_irqrestore(&uhci->lock, flags);
416 
417 	return retval;
418 }
419