xref: /openbmc/linux/drivers/usb/host/uhci-hub.c (revision 97da55fc)
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 OK(x)			len = (x); break
79 
80 #define CLR_RH_PORTSTAT(x) \
81 	status = uhci_readw(uhci, port_addr);	\
82 	status &= ~(RWC_BITS|WZ_BITS); \
83 	status &= ~(x); \
84 	status |= RWC_BITS & (x); \
85 	uhci_writew(uhci, status, port_addr)
86 
87 #define SET_RH_PORTSTAT(x) \
88 	status = uhci_readw(uhci, port_addr);	\
89 	status |= (x); \
90 	status &= ~(RWC_BITS|WZ_BITS); \
91 	uhci_writew(uhci, status, port_addr)
92 
93 /* UHCI controllers don't automatically stop resume signalling after 20 msec,
94  * so we have to poll and check timeouts in order to take care of it.
95  */
96 static void uhci_finish_suspend(struct uhci_hcd *uhci, int port,
97 		unsigned long port_addr)
98 {
99 	int status;
100 	int i;
101 
102 	if (uhci_readw(uhci, port_addr) & SUSPEND_BITS) {
103 		CLR_RH_PORTSTAT(SUSPEND_BITS);
104 		if (test_bit(port, &uhci->resuming_ports))
105 			set_bit(port, &uhci->port_c_suspend);
106 
107 		/* The controller won't actually turn off the RD bit until
108 		 * it has had a chance to send a low-speed EOP sequence,
109 		 * which is supposed to take 3 bit times (= 2 microseconds).
110 		 * Experiments show that some controllers take longer, so
111 		 * we'll poll for completion. */
112 		for (i = 0; i < 10; ++i) {
113 			if (!(uhci_readw(uhci, port_addr) & SUSPEND_BITS))
114 				break;
115 			udelay(1);
116 		}
117 	}
118 	clear_bit(port, &uhci->resuming_ports);
119 	usb_hcd_end_port_resume(&uhci_to_hcd(uhci)->self, port);
120 }
121 
122 /* Wait for the UHCI controller in HP's iLO2 server management chip.
123  * It can take up to 250 us to finish a reset and set the CSC bit.
124  */
125 static void wait_for_HP(struct uhci_hcd *uhci, unsigned long port_addr)
126 {
127 	int i;
128 
129 	for (i = 10; i < 250; i += 10) {
130 		if (uhci_readw(uhci, port_addr) & USBPORTSC_CSC)
131 			return;
132 		udelay(10);
133 	}
134 	/* Log a warning? */
135 }
136 
137 static void uhci_check_ports(struct uhci_hcd *uhci)
138 {
139 	unsigned int port;
140 	unsigned long port_addr;
141 	int status;
142 
143 	for (port = 0; port < uhci->rh_numports; ++port) {
144 		port_addr = USBPORTSC1 + 2 * port;
145 		status = uhci_readw(uhci, port_addr);
146 		if (unlikely(status & USBPORTSC_PR)) {
147 			if (time_after_eq(jiffies, uhci->ports_timeout)) {
148 				CLR_RH_PORTSTAT(USBPORTSC_PR);
149 				udelay(10);
150 
151 				/* HP's server management chip requires
152 				 * a longer delay. */
153 				if (uhci->wait_for_hp)
154 					wait_for_HP(uhci, port_addr);
155 
156 				/* If the port was enabled before, turning
157 				 * reset on caused a port enable change.
158 				 * Turning reset off causes a port connect
159 				 * status change.  Clear these changes. */
160 				CLR_RH_PORTSTAT(USBPORTSC_CSC | USBPORTSC_PEC);
161 				SET_RH_PORTSTAT(USBPORTSC_PE);
162 			}
163 		}
164 		if (unlikely(status & USBPORTSC_RD)) {
165 			if (!test_bit(port, &uhci->resuming_ports)) {
166 
167 				/* Port received a wakeup request */
168 				set_bit(port, &uhci->resuming_ports);
169 				uhci->ports_timeout = jiffies +
170 						msecs_to_jiffies(25);
171 				usb_hcd_start_port_resume(
172 						&uhci_to_hcd(uhci)->self, port);
173 
174 				/* Make sure we see the port again
175 				 * after the resuming period is over. */
176 				mod_timer(&uhci_to_hcd(uhci)->rh_timer,
177 						uhci->ports_timeout);
178 			} else if (time_after_eq(jiffies,
179 						uhci->ports_timeout)) {
180 				uhci_finish_suspend(uhci, port, port_addr);
181 			}
182 		}
183 	}
184 }
185 
186 static int uhci_hub_status_data(struct usb_hcd *hcd, char *buf)
187 {
188 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
189 	unsigned long flags;
190 	int status = 0;
191 
192 	spin_lock_irqsave(&uhci->lock, flags);
193 
194 	uhci_scan_schedule(uhci);
195 	if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
196 		goto done;
197 	uhci_check_ports(uhci);
198 
199 	status = get_hub_status_data(uhci, buf);
200 
201 	switch (uhci->rh_state) {
202 	    case UHCI_RH_SUSPENDED:
203 		/* if port change, ask to be resumed */
204 		if (status || uhci->resuming_ports) {
205 			status = 1;
206 			usb_hcd_resume_root_hub(hcd);
207 		}
208 		break;
209 
210 	    case UHCI_RH_AUTO_STOPPED:
211 		/* if port change, auto start */
212 		if (status)
213 			wakeup_rh(uhci);
214 		break;
215 
216 	    case UHCI_RH_RUNNING:
217 		/* are any devices attached? */
218 		if (!any_ports_active(uhci)) {
219 			uhci->rh_state = UHCI_RH_RUNNING_NODEVS;
220 			uhci->auto_stop_time = jiffies + HZ;
221 		}
222 		break;
223 
224 	    case UHCI_RH_RUNNING_NODEVS:
225 		/* auto-stop if nothing connected for 1 second */
226 		if (any_ports_active(uhci))
227 			uhci->rh_state = UHCI_RH_RUNNING;
228 		else if (time_after_eq(jiffies, uhci->auto_stop_time))
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, len = 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 		OK(4);		/* hub power */
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 		OK(4);
314 	case SetHubFeature:		/* We don't implement these */
315 	case ClearHubFeature:
316 		switch (wValue) {
317 		case C_HUB_OVER_CURRENT:
318 		case C_HUB_LOCAL_POWER:
319 			OK(0);
320 		default:
321 			goto err;
322 		}
323 		break;
324 	case SetPortFeature:
325 		if (port >= uhci->rh_numports)
326 			goto err;
327 
328 		switch (wValue) {
329 		case USB_PORT_FEAT_SUSPEND:
330 			SET_RH_PORTSTAT(USBPORTSC_SUSP);
331 			OK(0);
332 		case USB_PORT_FEAT_RESET:
333 			SET_RH_PORTSTAT(USBPORTSC_PR);
334 
335 			/* Reset terminates Resume signalling */
336 			uhci_finish_suspend(uhci, port, port_addr);
337 
338 			/* USB v2.0 7.1.7.5 */
339 			uhci->ports_timeout = jiffies + msecs_to_jiffies(50);
340 			OK(0);
341 		case USB_PORT_FEAT_POWER:
342 			/* UHCI has no power switching */
343 			OK(0);
344 		default:
345 			goto err;
346 		}
347 		break;
348 	case ClearPortFeature:
349 		if (port >= uhci->rh_numports)
350 			goto err;
351 
352 		switch (wValue) {
353 		case USB_PORT_FEAT_ENABLE:
354 			CLR_RH_PORTSTAT(USBPORTSC_PE);
355 
356 			/* Disable terminates Resume signalling */
357 			uhci_finish_suspend(uhci, port, port_addr);
358 			OK(0);
359 		case USB_PORT_FEAT_C_ENABLE:
360 			CLR_RH_PORTSTAT(USBPORTSC_PEC);
361 			OK(0);
362 		case USB_PORT_FEAT_SUSPEND:
363 			if (!(uhci_readw(uhci, port_addr) & USBPORTSC_SUSP)) {
364 
365 				/* Make certain the port isn't suspended */
366 				uhci_finish_suspend(uhci, port, port_addr);
367 			} else if (!test_and_set_bit(port,
368 						&uhci->resuming_ports)) {
369 				SET_RH_PORTSTAT(USBPORTSC_RD);
370 
371 				/* The controller won't allow RD to be set
372 				 * if the port is disabled.  When this happens
373 				 * just skip the Resume signalling.
374 				 */
375 				if (!(uhci_readw(uhci, port_addr) &
376 						USBPORTSC_RD))
377 					uhci_finish_suspend(uhci, port,
378 							port_addr);
379 				else
380 					/* USB v2.0 7.1.7.7 */
381 					uhci->ports_timeout = jiffies +
382 						msecs_to_jiffies(20);
383 			}
384 			OK(0);
385 		case USB_PORT_FEAT_C_SUSPEND:
386 			clear_bit(port, &uhci->port_c_suspend);
387 			OK(0);
388 		case USB_PORT_FEAT_POWER:
389 			/* UHCI has no power switching */
390 			goto err;
391 		case USB_PORT_FEAT_C_CONNECTION:
392 			CLR_RH_PORTSTAT(USBPORTSC_CSC);
393 			OK(0);
394 		case USB_PORT_FEAT_C_OVER_CURRENT:
395 			CLR_RH_PORTSTAT(USBPORTSC_OCC);
396 			OK(0);
397 		case USB_PORT_FEAT_C_RESET:
398 			/* this driver won't report these */
399 			OK(0);
400 		default:
401 			goto err;
402 		}
403 		break;
404 	case GetHubDescriptor:
405 		len = min_t(unsigned int, sizeof(root_hub_hub_des), wLength);
406 		memcpy(buf, root_hub_hub_des, len);
407 		if (len > 2)
408 			buf[2] = uhci->rh_numports;
409 		OK(len);
410 	default:
411 err:
412 		retval = -EPIPE;
413 	}
414 	spin_unlock_irqrestore(&uhci->lock, flags);
415 
416 	return retval;
417 }
418