xref: /openbmc/linux/drivers/usb/host/uhci-hub.c (revision 9f380456)
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 }
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(25);
170 
171 				/* Make sure we see the port again
172 				 * after the resuming period is over. */
173 				mod_timer(&uhci_to_hcd(uhci)->rh_timer,
174 						uhci->ports_timeout);
175 			} else if (time_after_eq(jiffies,
176 						uhci->ports_timeout)) {
177 				uhci_finish_suspend(uhci, port, port_addr);
178 			}
179 		}
180 	}
181 }
182 
183 static int uhci_hub_status_data(struct usb_hcd *hcd, char *buf)
184 {
185 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
186 	unsigned long flags;
187 	int status = 0;
188 
189 	spin_lock_irqsave(&uhci->lock, flags);
190 
191 	uhci_scan_schedule(uhci);
192 	if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
193 		goto done;
194 	uhci_check_ports(uhci);
195 
196 	status = get_hub_status_data(uhci, buf);
197 
198 	switch (uhci->rh_state) {
199 	    case UHCI_RH_SUSPENDED:
200 		/* if port change, ask to be resumed */
201 		if (status || uhci->resuming_ports) {
202 			status = 1;
203 			usb_hcd_resume_root_hub(hcd);
204 		}
205 		break;
206 
207 	    case UHCI_RH_AUTO_STOPPED:
208 		/* if port change, auto start */
209 		if (status)
210 			wakeup_rh(uhci);
211 		break;
212 
213 	    case UHCI_RH_RUNNING:
214 		/* are any devices attached? */
215 		if (!any_ports_active(uhci)) {
216 			uhci->rh_state = UHCI_RH_RUNNING_NODEVS;
217 			uhci->auto_stop_time = jiffies + HZ;
218 		}
219 		break;
220 
221 	    case UHCI_RH_RUNNING_NODEVS:
222 		/* auto-stop if nothing connected for 1 second */
223 		if (any_ports_active(uhci))
224 			uhci->rh_state = UHCI_RH_RUNNING;
225 		else if (time_after_eq(jiffies, uhci->auto_stop_time))
226 			suspend_rh(uhci, UHCI_RH_AUTO_STOPPED);
227 		break;
228 
229 	    default:
230 		break;
231 	}
232 
233 done:
234 	spin_unlock_irqrestore(&uhci->lock, flags);
235 	return status;
236 }
237 
238 /* size of returned buffer is part of USB spec */
239 static int uhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
240 			u16 wIndex, char *buf, u16 wLength)
241 {
242 	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
243 	int status, lstatus, retval = 0, len = 0;
244 	unsigned int port = wIndex - 1;
245 	unsigned long port_addr = USBPORTSC1 + 2 * port;
246 	u16 wPortChange, wPortStatus;
247 	unsigned long flags;
248 
249 	if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
250 		return -ETIMEDOUT;
251 
252 	spin_lock_irqsave(&uhci->lock, flags);
253 	switch (typeReq) {
254 
255 	case GetHubStatus:
256 		*(__le32 *)buf = cpu_to_le32(0);
257 		OK(4);		/* hub power */
258 	case GetPortStatus:
259 		if (port >= uhci->rh_numports)
260 			goto err;
261 
262 		uhci_check_ports(uhci);
263 		status = uhci_readw(uhci, port_addr);
264 
265 		/* Intel controllers report the OverCurrent bit active on.
266 		 * VIA controllers report it active off, so we'll adjust the
267 		 * bit value.  (It's not standardized in the UHCI spec.)
268 		 */
269 		if (uhci->oc_low)
270 			status ^= USBPORTSC_OC;
271 
272 		/* UHCI doesn't support C_RESET (always false) */
273 		wPortChange = lstatus = 0;
274 		if (status & USBPORTSC_CSC)
275 			wPortChange |= USB_PORT_STAT_C_CONNECTION;
276 		if (status & USBPORTSC_PEC)
277 			wPortChange |= USB_PORT_STAT_C_ENABLE;
278 		if ((status & USBPORTSC_OCC) && !ignore_oc)
279 			wPortChange |= USB_PORT_STAT_C_OVERCURRENT;
280 
281 		if (test_bit(port, &uhci->port_c_suspend)) {
282 			wPortChange |= USB_PORT_STAT_C_SUSPEND;
283 			lstatus |= 1;
284 		}
285 		if (test_bit(port, &uhci->resuming_ports))
286 			lstatus |= 4;
287 
288 		/* UHCI has no power switching (always on) */
289 		wPortStatus = USB_PORT_STAT_POWER;
290 		if (status & USBPORTSC_CCS)
291 			wPortStatus |= USB_PORT_STAT_CONNECTION;
292 		if (status & USBPORTSC_PE) {
293 			wPortStatus |= USB_PORT_STAT_ENABLE;
294 			if (status & SUSPEND_BITS)
295 				wPortStatus |= USB_PORT_STAT_SUSPEND;
296 		}
297 		if (status & USBPORTSC_OC)
298 			wPortStatus |= USB_PORT_STAT_OVERCURRENT;
299 		if (status & USBPORTSC_PR)
300 			wPortStatus |= USB_PORT_STAT_RESET;
301 		if (status & USBPORTSC_LSDA)
302 			wPortStatus |= USB_PORT_STAT_LOW_SPEED;
303 
304 		if (wPortChange)
305 			dev_dbg(uhci_dev(uhci), "port %d portsc %04x,%02x\n",
306 					wIndex, status, lstatus);
307 
308 		*(__le16 *)buf = cpu_to_le16(wPortStatus);
309 		*(__le16 *)(buf + 2) = cpu_to_le16(wPortChange);
310 		OK(4);
311 	case SetHubFeature:		/* We don't implement these */
312 	case ClearHubFeature:
313 		switch (wValue) {
314 		case C_HUB_OVER_CURRENT:
315 		case C_HUB_LOCAL_POWER:
316 			OK(0);
317 		default:
318 			goto err;
319 		}
320 		break;
321 	case SetPortFeature:
322 		if (port >= uhci->rh_numports)
323 			goto err;
324 
325 		switch (wValue) {
326 		case USB_PORT_FEAT_SUSPEND:
327 			SET_RH_PORTSTAT(USBPORTSC_SUSP);
328 			OK(0);
329 		case USB_PORT_FEAT_RESET:
330 			SET_RH_PORTSTAT(USBPORTSC_PR);
331 
332 			/* Reset terminates Resume signalling */
333 			uhci_finish_suspend(uhci, port, port_addr);
334 
335 			/* USB v2.0 7.1.7.5 */
336 			uhci->ports_timeout = jiffies + msecs_to_jiffies(50);
337 			OK(0);
338 		case USB_PORT_FEAT_POWER:
339 			/* UHCI has no power switching */
340 			OK(0);
341 		default:
342 			goto err;
343 		}
344 		break;
345 	case ClearPortFeature:
346 		if (port >= uhci->rh_numports)
347 			goto err;
348 
349 		switch (wValue) {
350 		case USB_PORT_FEAT_ENABLE:
351 			CLR_RH_PORTSTAT(USBPORTSC_PE);
352 
353 			/* Disable terminates Resume signalling */
354 			uhci_finish_suspend(uhci, port, port_addr);
355 			OK(0);
356 		case USB_PORT_FEAT_C_ENABLE:
357 			CLR_RH_PORTSTAT(USBPORTSC_PEC);
358 			OK(0);
359 		case USB_PORT_FEAT_SUSPEND:
360 			if (!(uhci_readw(uhci, port_addr) & USBPORTSC_SUSP)) {
361 
362 				/* Make certain the port isn't suspended */
363 				uhci_finish_suspend(uhci, port, port_addr);
364 			} else if (!test_and_set_bit(port,
365 						&uhci->resuming_ports)) {
366 				SET_RH_PORTSTAT(USBPORTSC_RD);
367 
368 				/* The controller won't allow RD to be set
369 				 * if the port is disabled.  When this happens
370 				 * just skip the Resume signalling.
371 				 */
372 				if (!(uhci_readw(uhci, port_addr) &
373 						USBPORTSC_RD))
374 					uhci_finish_suspend(uhci, port,
375 							port_addr);
376 				else
377 					/* USB v2.0 7.1.7.7 */
378 					uhci->ports_timeout = jiffies +
379 						msecs_to_jiffies(20);
380 			}
381 			OK(0);
382 		case USB_PORT_FEAT_C_SUSPEND:
383 			clear_bit(port, &uhci->port_c_suspend);
384 			OK(0);
385 		case USB_PORT_FEAT_POWER:
386 			/* UHCI has no power switching */
387 			goto err;
388 		case USB_PORT_FEAT_C_CONNECTION:
389 			CLR_RH_PORTSTAT(USBPORTSC_CSC);
390 			OK(0);
391 		case USB_PORT_FEAT_C_OVER_CURRENT:
392 			CLR_RH_PORTSTAT(USBPORTSC_OCC);
393 			OK(0);
394 		case USB_PORT_FEAT_C_RESET:
395 			/* this driver won't report these */
396 			OK(0);
397 		default:
398 			goto err;
399 		}
400 		break;
401 	case GetHubDescriptor:
402 		len = min_t(unsigned int, sizeof(root_hub_hub_des), wLength);
403 		memcpy(buf, root_hub_hub_des, len);
404 		if (len > 2)
405 			buf[2] = uhci->rh_numports;
406 		OK(len);
407 	default:
408 err:
409 		retval = -EPIPE;
410 	}
411 	spin_unlock_irqrestore(&uhci->lock, flags);
412 
413 	return retval;
414 }
415