USB: EHCI & UHCI: fix race between root-hub suspend and port resume
[deliverable/linux.git] / drivers / usb / host / uhci-hub.c
CommitLineData
1da177e4
LT
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
bef4665a 15static const __u8 root_hub_hub_des[] =
1da177e4
LT
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
88018158
AS
36/* suspend/resume bits: port suspended or port resuming */
37#define SUSPEND_BITS (USBPORTSC_SUSP | USBPORTSC_RD)
38
f5946f82
AS
39/* A port that either is connected or has a changed-bit set will prevent
40 * us from AUTO_STOPPING.
41 */
42static int any_ports_active(struct uhci_hcd *uhci)
43{
44 int port;
45
46 for (port = 0; port < uhci->rh_numports; ++port) {
47 if ((inw(uhci->io_addr + 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
6c1b445c 55static inline int get_hub_status_data(struct uhci_hcd *uhci, char *buf)
1da177e4 56{
1da177e4 57 int port;
5f8364b7
AS
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;
1da177e4
LT
68
69 *buf = 0;
70 for (port = 0; port < uhci->rh_numports; ++port) {
5f8364b7 71 if ((inw(uhci->io_addr + USBPORTSC1 + port * 2) & mask) ||
1da177e4
LT
72 test_bit(port, &uhci->port_c_suspend))
73 *buf |= (1 << (port + 1));
74 }
1da177e4
LT
75 return !!*buf;
76}
77
78#define OK(x) len = (x); break
79
80#define CLR_RH_PORTSTAT(x) \
81 status = inw(port_addr); \
82 status &= ~(RWC_BITS|WZ_BITS); \
83 status &= ~(x); \
84 status |= RWC_BITS & (x); \
85 outw(status, port_addr)
86
87#define SET_RH_PORTSTAT(x) \
88 status = inw(port_addr); \
89 status |= (x); \
90 status &= ~(RWC_BITS|WZ_BITS); \
91 outw(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 */
96static void uhci_finish_suspend(struct uhci_hcd *uhci, int port,
97 unsigned long port_addr)
98{
99 int status;
de06a3b8 100 int i;
1da177e4 101
88018158
AS
102 if (inw(port_addr) & SUSPEND_BITS) {
103 CLR_RH_PORTSTAT(SUSPEND_BITS);
8e326406
AS
104 if (test_bit(port, &uhci->resuming_ports))
105 set_bit(port, &uhci->port_c_suspend);
1da177e4
LT
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,
de06a3b8
AS
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) {
88018158 113 if (!(inw(port_addr) & SUSPEND_BITS))
de06a3b8
AS
114 break;
115 udelay(1);
116 }
1da177e4 117 }
8e326406 118 clear_bit(port, &uhci->resuming_ports);
1da177e4
LT
119}
120
ae557175
AS
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 */
124static void wait_for_HP(unsigned long port_addr)
125{
126 int i;
127
128 for (i = 10; i < 250; i += 10) {
129 if (inw(port_addr) & USBPORTSC_CSC)
130 return;
131 udelay(10);
132 }
133 /* Log a warning? */
134}
135
1da177e4
LT
136static 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 = uhci->io_addr + USBPORTSC1 + 2 * port;
144 status = inw(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
ae557175
AS
150 /* HP's server management chip requires
151 * a longer delay. */
152 if (to_pci_dev(uhci_dev(uhci))->vendor ==
153 PCI_VENDOR_ID_HP)
154 wait_for_HP(port_addr);
155
1da177e4
LT
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(20);
6c1b445c
AS
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);
1da177e4
LT
176 } else if (time_after_eq(jiffies,
177 uhci->ports_timeout)) {
178 uhci_finish_suspend(uhci, port, port_addr);
179 }
180 }
181 }
182}
183
6c1b445c
AS
184static 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;
1f09df8b 188 int status = 0;
6c1b445c
AS
189
190 spin_lock_irqsave(&uhci->lock, flags);
6c1b445c 191
7d12e780 192 uhci_scan_schedule(uhci);
e323de46 193 if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags) || uhci->dead)
1f09df8b 194 goto done;
6c1b445c 195 uhci_check_ports(uhci);
1f09df8b 196
6c1b445c
AS
197 status = get_hub_status_data(uhci, buf);
198
199 switch (uhci->rh_state) {
200 case UHCI_RH_SUSPENDING:
201 case UHCI_RH_SUSPENDED:
202 /* if port change, ask to be resumed */
203 if (status)
204 usb_hcd_resume_root_hub(hcd);
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
233done:
234 spin_unlock_irqrestore(&uhci->lock, flags);
235 return status;
236}
237
1da177e4
LT
238/* size of returned buffer is part of USB spec */
239static 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 = uhci->io_addr + USBPORTSC1 + 2 * port;
246 u16 wPortChange, wPortStatus;
247 unsigned long flags;
248
e323de46 249 if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags) || uhci->dead)
a8bed8b6
AS
250 return -ETIMEDOUT;
251
1da177e4
LT
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 = inw(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 (to_pci_dev(hcd->self.controller)->vendor ==
270 PCI_VENDOR_ID_VIA)
271 status ^= USBPORTSC_OC;
272
273 /* UHCI doesn't support C_RESET (always false) */
274 wPortChange = lstatus = 0;
275 if (status & USBPORTSC_CSC)
276 wPortChange |= USB_PORT_STAT_C_CONNECTION;
277 if (status & USBPORTSC_PEC)
278 wPortChange |= USB_PORT_STAT_C_ENABLE;
5f8364b7 279 if ((status & USBPORTSC_OCC) && !ignore_oc)
1da177e4
LT
280 wPortChange |= USB_PORT_STAT_C_OVERCURRENT;
281
282 if (test_bit(port, &uhci->port_c_suspend)) {
283 wPortChange |= USB_PORT_STAT_C_SUSPEND;
284 lstatus |= 1;
285 }
1da177e4
LT
286 if (test_bit(port, &uhci->resuming_ports))
287 lstatus |= 4;
288
289 /* UHCI has no power switching (always on) */
290 wPortStatus = USB_PORT_STAT_POWER;
291 if (status & USBPORTSC_CCS)
292 wPortStatus |= USB_PORT_STAT_CONNECTION;
293 if (status & USBPORTSC_PE) {
294 wPortStatus |= USB_PORT_STAT_ENABLE;
88018158 295 if (status & SUSPEND_BITS)
1da177e4
LT
296 wPortStatus |= USB_PORT_STAT_SUSPEND;
297 }
298 if (status & USBPORTSC_OC)
299 wPortStatus |= USB_PORT_STAT_OVERCURRENT;
300 if (status & USBPORTSC_PR)
301 wPortStatus |= USB_PORT_STAT_RESET;
302 if (status & USBPORTSC_LSDA)
303 wPortStatus |= USB_PORT_STAT_LOW_SPEED;
304
305 if (wPortChange)
306 dev_dbg(uhci_dev(uhci), "port %d portsc %04x,%02x\n",
307 wIndex, status, lstatus);
308
309 *(__le16 *)buf = cpu_to_le16(wPortStatus);
310 *(__le16 *)(buf + 2) = cpu_to_le16(wPortChange);
311 OK(4);
312 case SetHubFeature: /* We don't implement these */
313 case ClearHubFeature:
314 switch (wValue) {
315 case C_HUB_OVER_CURRENT:
316 case C_HUB_LOCAL_POWER:
317 OK(0);
318 default:
319 goto err;
320 }
321 break;
322 case SetPortFeature:
323 if (port >= uhci->rh_numports)
324 goto err;
325
326 switch (wValue) {
327 case USB_PORT_FEAT_SUSPEND:
1da177e4
LT
328 SET_RH_PORTSTAT(USBPORTSC_SUSP);
329 OK(0);
330 case USB_PORT_FEAT_RESET:
331 SET_RH_PORTSTAT(USBPORTSC_PR);
332
333 /* Reset terminates Resume signalling */
334 uhci_finish_suspend(uhci, port, port_addr);
335
336 /* USB v2.0 7.1.7.5 */
337 uhci->ports_timeout = jiffies + msecs_to_jiffies(50);
338 OK(0);
339 case USB_PORT_FEAT_POWER:
340 /* UHCI has no power switching */
341 OK(0);
342 default:
343 goto err;
344 }
345 break;
346 case ClearPortFeature:
347 if (port >= uhci->rh_numports)
348 goto err;
349
350 switch (wValue) {
351 case USB_PORT_FEAT_ENABLE:
352 CLR_RH_PORTSTAT(USBPORTSC_PE);
353
354 /* Disable terminates Resume signalling */
355 uhci_finish_suspend(uhci, port, port_addr);
356 OK(0);
357 case USB_PORT_FEAT_C_ENABLE:
358 CLR_RH_PORTSTAT(USBPORTSC_PEC);
359 OK(0);
360 case USB_PORT_FEAT_SUSPEND:
8e326406
AS
361 if (!(inw(port_addr) & USBPORTSC_SUSP)) {
362
363 /* Make certain the port isn't suspended */
364 uhci_finish_suspend(uhci, port, port_addr);
365 } else if (!test_and_set_bit(port,
1da177e4
LT
366 &uhci->resuming_ports)) {
367 SET_RH_PORTSTAT(USBPORTSC_RD);
368
369 /* The controller won't allow RD to be set
370 * if the port is disabled. When this happens
371 * just skip the Resume signalling.
372 */
373 if (!(inw(port_addr) & 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:
408err:
409 retval = -EPIPE;
410 }
411 spin_unlock_irqrestore(&uhci->lock, flags);
412
413 return retval;
414}
This page took 0.518832 seconds and 5 git commands to generate.