drivers/usb/host/uhci-hub.c

   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
  16 static 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  */
  44 static 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
  57 static 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  */
  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(USB_RESUME_TIMEOUT);
 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                                 !uhci->wait_for_hp)
 230                         suspend_rh(uhci, UHCI_RH_AUTO_STOPPED);
 231                 break;
 232
 233             default:
 234                 break;
 235         }
 236
 237 done:
 238         spin_unlock_irqrestore(&uhci->lock, flags);
 239         return status;
 240 }
 241
 242 /* size of returned buffer is part of USB spec */
 243 static 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, 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, 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(port,
 372                                                 &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, 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(20);
 387                         }
 388                         break;
 389                 case USB_PORT_FEAT_C_SUSPEND:
 390                         clear_bit(port, &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(buf, root_hub_hub_des, retval);
 411                 if (retval > 2)
 412                         buf[2] = uhci->rh_numports;
 413                 break;
 414         default:
 415 err:
 416                 retval = -EPIPE;
 417         }
 418         spin_unlock_irqrestore(&uhci->lock, flags);
 419
 420         return retval;
 421 }