1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Universal Host Controller Interface driver for USB.
4 *
5 * Maintainer: Alan Stern <stern@rowland.harvard.edu>
6 *
7 * (C) Copyright 1999 Linus Torvalds
8 * (C) Copyright 1999-2002 Johannes Erdfelt, johannes@erdfelt.com
9 * (C) Copyright 1999 Randy Dunlap
10 * (C) Copyright 1999 Georg Acher, acher@in.tum.de
11 * (C) Copyright 1999 Deti Fliegl, deti@fliegl.de
12 * (C) Copyright 1999 Thomas Sailer, sailer@ife.ee.ethz.ch
13 * (C) Copyright 2004 Alan Stern, stern@rowland.harvard.edu
14 */
15
16static const __u8 root_hub_hub_des[] =
17{
18 0x09, /* __u8 bLength; */
19 USB_DT_HUB, /* __u8 bDescriptorType; Hub-descriptor */
20 0x02, /* __u8 bNbrPorts; */
21 HUB_CHAR_NO_LPSM | /* __u16 wHubCharacteristics; */
22 HUB_CHAR_INDV_PORT_OCPM, /* (per-port OC, no power switching) */
23 0x00,
24 0x01, /* __u8 bPwrOn2pwrGood; 2ms */
25 0x00, /* __u8 bHubContrCurrent; 0 mA */
26 0x00, /* __u8 DeviceRemovable; *** 7 Ports max */
27 0xff /* __u8 PortPwrCtrlMask; *** 7 ports max */
28};
29
30#define UHCI_RH_MAXCHILD 7
31
32/* must write as zeroes */
33#define WZ_BITS (USBPORTSC_RES2 | USBPORTSC_RES3 | USBPORTSC_RES4)
34
35/* status change bits: nonzero writes will clear */
36#define RWC_BITS (USBPORTSC_OCC | USBPORTSC_PEC | USBPORTSC_CSC)
37
38/* suspend/resume bits: port suspended or port resuming */
39#define SUSPEND_BITS (USBPORTSC_SUSP | USBPORTSC_RD)
40
41/* A port that either is connected or has a changed-bit set will prevent
42 * us from AUTO_STOPPING.
43 */
44static int any_ports_active(struct uhci_hcd *uhci)
45{
46 int port;
47
48 for (port = 0; port < uhci->rh_numports; ++port) {
49 if ((uhci_readw(uhci, USBPORTSC1 + port * 2) &
50 (USBPORTSC_CCS | RWC_BITS)) ||
51 test_bit(port, &uhci->port_c_suspend))
52 return 1;
53 }
54 return 0;
55}
56
57static inline int get_hub_status_data(struct uhci_hcd *uhci, char *buf)
58{
59 int port;
60 int mask = RWC_BITS;
61
62 /* Some boards (both VIA and Intel apparently) report bogus
63 * overcurrent indications, causing massive log spam unless
64 * we completely ignore them. This doesn't seem to be a problem
65 * with the chipset so much as with the way it is connected on
66 * the motherboard; if the overcurrent input is left to float
67 * then it may constantly register false positives. */
68 if (ignore_oc)
69 mask &= ~USBPORTSC_OCC;
70
71 *buf = 0;
72 for (port = 0; port < uhci->rh_numports; ++port) {
73 if ((uhci_readw(uhci, USBPORTSC1 + port * 2) & mask) ||
74 test_bit(port, &uhci->port_c_suspend))
75 *buf |= (1 << (port + 1));
76 }
77 return !!*buf;
78}
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 */
96static 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, reg: port_addr) & SUSPEND_BITS) {
103 CLR_RH_PORTSTAT(SUSPEND_BITS);
104 if (test_bit(port, &uhci->resuming_ports))
105 set_bit(nr: port, addr: &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, reg: port_addr) & SUSPEND_BITS))
114 break;
115 udelay(usec: 1);
116 }
117 }
118 clear_bit(nr: port, addr: &uhci->resuming_ports);
119 usb_hcd_end_port_resume(bus: &uhci_to_hcd(uhci)->self, portnum: 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 */
125static 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, reg: port_addr) & USBPORTSC_CSC)
131 return;
132 udelay(usec: 10);
133 }
134 /* Log a warning? */
135}
136
137static 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, reg: 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(usec: 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(nr: port, addr: &uhci->resuming_ports);
169 uhci->ports_timeout = jiffies +
170 msecs_to_jiffies(USB_RESUME_TIMEOUT);
171 usb_hcd_start_port_resume(
172 bus: &uhci_to_hcd(uhci)->self, portnum: port);
173
174 /* Make sure we see the port again
175 * after the resuming period is over. */
176 mod_timer(timer: &uhci_to_hcd(uhci)->rh_timer,
177 expires: 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
186static 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 !uhci->wait_for_hp)
230 suspend_rh(uhci, new_state: UHCI_RH_AUTO_STOPPED);
231 break;
232
233 default:
234 break;
235 }
236
237done:
238 spin_unlock_irqrestore(lock: &uhci->lock, flags);
239 return status;
240}
241
242/* size of returned buffer is part of USB spec */
243static int uhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
244 u16 wIndex, char *buf, u16 wLength)
245{
246 struct uhci_hcd *uhci = hcd_to_uhci(hcd);
247 int status, lstatus, retval = 0;
248 unsigned int port = wIndex - 1;
249 unsigned long port_addr = USBPORTSC1 + 2 * port;
250 u16 wPortChange, wPortStatus;
251 unsigned long flags;
252
253 if (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
254 return -ETIMEDOUT;
255
256 spin_lock_irqsave(&uhci->lock, flags);
257 switch (typeReq) {
258
259 case GetHubStatus:
260 *(__le32 *)buf = cpu_to_le32(0);
261 retval = 4; /* hub power */
262 break;
263 case GetPortStatus:
264 if (port >= uhci->rh_numports)
265 goto err;
266
267 uhci_check_ports(uhci);
268 status = uhci_readw(uhci, reg: port_addr);
269
270 /* Intel controllers report the OverCurrent bit active on.
271 * VIA controllers report it active off, so we'll adjust the
272 * bit value. (It's not standardized in the UHCI spec.)
273 */
274 if (uhci->oc_low)
275 status ^= USBPORTSC_OC;
276
277 /* UHCI doesn't support C_RESET (always false) */
278 wPortChange = lstatus = 0;
279 if (status & USBPORTSC_CSC)
280 wPortChange |= USB_PORT_STAT_C_CONNECTION;
281 if (status & USBPORTSC_PEC)
282 wPortChange |= USB_PORT_STAT_C_ENABLE;
283 if ((status & USBPORTSC_OCC) && !ignore_oc)
284 wPortChange |= USB_PORT_STAT_C_OVERCURRENT;
285
286 if (test_bit(port, &uhci->port_c_suspend)) {
287 wPortChange |= USB_PORT_STAT_C_SUSPEND;
288 lstatus |= 1;
289 }
290 if (test_bit(port, &uhci->resuming_ports))
291 lstatus |= 4;
292
293 /* UHCI has no power switching (always on) */
294 wPortStatus = USB_PORT_STAT_POWER;
295 if (status & USBPORTSC_CCS)
296 wPortStatus |= USB_PORT_STAT_CONNECTION;
297 if (status & USBPORTSC_PE) {
298 wPortStatus |= USB_PORT_STAT_ENABLE;
299 if (status & SUSPEND_BITS)
300 wPortStatus |= USB_PORT_STAT_SUSPEND;
301 }
302 if (status & USBPORTSC_OC)
303 wPortStatus |= USB_PORT_STAT_OVERCURRENT;
304 if (status & USBPORTSC_PR)
305 wPortStatus |= USB_PORT_STAT_RESET;
306 if (status & USBPORTSC_LSDA)
307 wPortStatus |= USB_PORT_STAT_LOW_SPEED;
308
309 if (wPortChange)
310 dev_dbg(uhci_dev(uhci), "port %d portsc %04x,%02x\n",
311 wIndex, status, lstatus);
312
313 *(__le16 *)buf = cpu_to_le16(wPortStatus);
314 *(__le16 *)(buf + 2) = cpu_to_le16(wPortChange);
315 retval = 4;
316 break;
317 case SetHubFeature: /* We don't implement these */
318 case ClearHubFeature:
319 switch (wValue) {
320 case C_HUB_OVER_CURRENT:
321 case C_HUB_LOCAL_POWER:
322 break;
323 default:
324 goto err;
325 }
326 break;
327 case SetPortFeature:
328 if (port >= uhci->rh_numports)
329 goto err;
330
331 switch (wValue) {
332 case USB_PORT_FEAT_SUSPEND:
333 SET_RH_PORTSTAT(USBPORTSC_SUSP);
334 break;
335 case USB_PORT_FEAT_RESET:
336 SET_RH_PORTSTAT(USBPORTSC_PR);
337
338 /* Reset terminates Resume signalling */
339 uhci_finish_suspend(uhci, port, port_addr);
340
341 /* USB v2.0 7.1.7.5 */
342 uhci->ports_timeout = jiffies +
343 msecs_to_jiffies(USB_RESUME_TIMEOUT);
344 break;
345 case USB_PORT_FEAT_POWER:
346 /* UHCI has no power switching */
347 break;
348 default:
349 goto err;
350 }
351 break;
352 case ClearPortFeature:
353 if (port >= uhci->rh_numports)
354 goto err;
355
356 switch (wValue) {
357 case USB_PORT_FEAT_ENABLE:
358 CLR_RH_PORTSTAT(USBPORTSC_PE);
359
360 /* Disable terminates Resume signalling */
361 uhci_finish_suspend(uhci, port, port_addr);
362 break;
363 case USB_PORT_FEAT_C_ENABLE:
364 CLR_RH_PORTSTAT(USBPORTSC_PEC);
365 break;
366 case USB_PORT_FEAT_SUSPEND:
367 if (!(uhci_readw(uhci, reg: port_addr) & USBPORTSC_SUSP)) {
368
369 /* Make certain the port isn't suspended */
370 uhci_finish_suspend(uhci, port, port_addr);
371 } else if (!test_and_set_bit(nr: port,
372 addr: &uhci->resuming_ports)) {
373 SET_RH_PORTSTAT(USBPORTSC_RD);
374
375 /* The controller won't allow RD to be set
376 * if the port is disabled. When this happens
377 * just skip the Resume signalling.
378 */
379 if (!(uhci_readw(uhci, reg: port_addr) &
380 USBPORTSC_RD))
381 uhci_finish_suspend(uhci, port,
382 port_addr);
383 else
384 /* USB v2.0 7.1.7.7 */
385 uhci->ports_timeout = jiffies +
386 msecs_to_jiffies(m: 20);
387 }
388 break;
389 case USB_PORT_FEAT_C_SUSPEND:
390 clear_bit(nr: port, addr: &uhci->port_c_suspend);
391 break;
392 case USB_PORT_FEAT_POWER:
393 /* UHCI has no power switching */
394 goto err;
395 case USB_PORT_FEAT_C_CONNECTION:
396 CLR_RH_PORTSTAT(USBPORTSC_CSC);
397 break;
398 case USB_PORT_FEAT_C_OVER_CURRENT:
399 CLR_RH_PORTSTAT(USBPORTSC_OCC);
400 break;
401 case USB_PORT_FEAT_C_RESET:
402 /* this driver won't report these */
403 break;
404 default:
405 goto err;
406 }
407 break;
408 case GetHubDescriptor:
409 retval = min_t(unsigned int, sizeof(root_hub_hub_des), wLength);
410 memcpy(to: buf, from: root_hub_hub_des, len: retval);
411 if (retval > 2)
412 buf[2] = uhci->rh_numports;
413 break;
414 default:
415err:
416 retval = -EPIPE;
417 }
418 spin_unlock_irqrestore(lock: &uhci->lock, flags);
419
420 return retval;
421}
422