drivers/usb/musb/musb_virthub.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * MUSB OTG driver virtual root hub support
   4  *
   5  * Copyright 2005 Mentor Graphics Corporation
   6  * Copyright (C) 2005-2006 by Texas Instruments
   7  * Copyright (C) 2006-2007 Nokia Corporation
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/kernel.h>
  12 #include <linux/sched.h>
  13 #include <linux/errno.h>
  14 #include <linux/time.h>
  15 #include <linux/timer.h>
  16
  17 #include <asm/unaligned.h>
  18
  19 #include "musb_core.h"
  20
  21 void musb_host_finish_resume(struct work_struct *work)
  22 {
  23         struct musb *musb;
  24         unsigned long flags;
  25         u8 power;
  26
  27         musb = container_of(work, struct musb, finish_resume_work.work);
  28
  29         spin_lock_irqsave(&musb->lock, flags);
  30
  31         power = musb_readb(musb->mregs, MUSB_POWER);
  32         power &= ~MUSB_POWER_RESUME;
  33         musb_dbg(musb, "root port resume stopped, power %02x", power);
  34         musb_writeb(musb->mregs, MUSB_POWER, power);
  35
  36         /*
  37          * ISSUE:  DaVinci (RTL 1.300) disconnects after
  38          * resume of high speed peripherals (but not full
  39          * speed ones).
  40          */
  41         musb->is_active = 1;
  42         musb->port1_status &= ~(USB_PORT_STAT_SUSPEND | MUSB_PORT_STAT_RESUME);
  43         musb->port1_status |= USB_PORT_STAT_C_SUSPEND << 16;
  44         usb_hcd_poll_rh_status(musb->hcd);
  45         /* NOTE: it might really be A_WAIT_BCON ... */
  46         musb->xceiv->otg->state = OTG_STATE_A_HOST;
  47
  48         spin_unlock_irqrestore(&musb->lock, flags);
  49 }
  50
  51 int musb_port_suspend(struct musb *musb, bool do_suspend)
  52 {
  53         struct usb_otg  *otg = musb->xceiv->otg;
  54         u8              power;
  55         void __iomem    *mbase = musb->mregs;
  56
  57         if (!is_host_active(musb))
  58                 return 0;
  59
  60         /* NOTE:  this doesn't necessarily put PHY into low power mode,
  61          * turning off its clock; that's a function of PHY integration and
  62          * MUSB_POWER_ENSUSPEND.  PHY may need a clock (sigh) to detect
  63          * SE0 changing to connect (J) or wakeup (K) states.
  64          */
  65         power = musb_readb(mbase, MUSB_POWER);
  66         if (do_suspend) {
  67                 int retries = 10000;
  68
  69                 if (power & MUSB_POWER_RESUME)
  70                         return -EBUSY;
  71
  72                 if (!(power & MUSB_POWER_SUSPENDM)) {
  73                         power |= MUSB_POWER_SUSPENDM;
  74                         musb_writeb(mbase, MUSB_POWER, power);
  75
  76                         /* Needed for OPT A tests */
  77                         power = musb_readb(mbase, MUSB_POWER);
  78                         while (power & MUSB_POWER_SUSPENDM) {
  79                                 power = musb_readb(mbase, MUSB_POWER);
  80                                 if (retries-- < 1)
  81                                         break;
  82                         }
  83                 }
  84
  85                 musb_dbg(musb, "Root port suspended, power %02x", power);
  86
  87                 musb->port1_status |= USB_PORT_STAT_SUSPEND;
  88                 switch (musb->xceiv->otg->state) {
  89                 case OTG_STATE_A_HOST:
  90                         musb->xceiv->otg->state = OTG_STATE_A_SUSPEND;
  91                         musb->is_active = otg->host->b_hnp_enable;
  92                         if (musb->is_active)
  93                                 mod_timer(&musb->otg_timer, jiffies
  94                                         + msecs_to_jiffies(
  95                                                 OTG_TIME_A_AIDL_BDIS));
  96                         musb_platform_try_idle(musb, 0);
  97                         break;
  98                 case OTG_STATE_B_HOST:
  99                         musb->xceiv->otg->state = OTG_STATE_B_WAIT_ACON;
 100                         musb->is_active = otg->host->b_hnp_enable;
 101                         musb_platform_try_idle(musb, 0);
 102                         break;
 103                 default:
 104                         musb_dbg(musb, "bogus rh suspend? %s",
 105                                 usb_otg_state_string(musb->xceiv->otg->state));
 106                 }
 107         } else if (power & MUSB_POWER_SUSPENDM) {
 108                 power &= ~MUSB_POWER_SUSPENDM;
 109                 power |= MUSB_POWER_RESUME;
 110                 musb_writeb(mbase, MUSB_POWER, power);
 111
 112                 musb_dbg(musb, "Root port resuming, power %02x", power);
 113
 114                 musb->port1_status |= MUSB_PORT_STAT_RESUME;
 115                 schedule_delayed_work(&musb->finish_resume_work,
 116                                       msecs_to_jiffies(USB_RESUME_TIMEOUT));
 117         }
 118         return 0;
 119 }
 120
 121 void musb_port_reset(struct musb *musb, bool do_reset)
 122 {
 123         u8              power;
 124         void __iomem    *mbase = musb->mregs;
 125
 126         if (musb->xceiv->otg->state == OTG_STATE_B_IDLE) {
 127                 musb_dbg(musb, "HNP: Returning from HNP; no hub reset from b_idle");
 128                 musb->port1_status &= ~USB_PORT_STAT_RESET;
 129                 return;
 130         }
 131
 132         if (!is_host_active(musb))
 133                 return;
 134
 135         /* NOTE:  caller guarantees it will turn off the reset when
 136          * the appropriate amount of time has passed
 137          */
 138         power = musb_readb(mbase, MUSB_POWER);
 139         if (do_reset) {
 140                 /*
 141                  * If RESUME is set, we must make sure it stays minimum 20 ms.
 142                  * Then we must clear RESUME and wait a bit to let musb start
 143                  * generating SOFs. If we don't do this, OPT HS A 6.8 tests
 144                  * fail with "Error! Did not receive an SOF before suspend
 145                  * detected".
 146                  */
 147                 if (power &  MUSB_POWER_RESUME) {
 148                         long remain = (unsigned long) musb->rh_timer - jiffies;
 149
 150                         if (musb->rh_timer > 0 && remain > 0) {
 151                                 /* take into account the minimum delay after resume */
 152                                 schedule_delayed_work(
 153                                         &musb->deassert_reset_work, remain);
 154                                 return;
 155                         }
 156
 157                         musb_writeb(mbase, MUSB_POWER,
 158                                     power & ~MUSB_POWER_RESUME);
 159
 160                         /* Give the core 1 ms to clear MUSB_POWER_RESUME */
 161                         schedule_delayed_work(&musb->deassert_reset_work,
 162                                               msecs_to_jiffies(1));
 163                         return;
 164                 }
 165
 166                 power &= 0xf0;
 167                 musb_writeb(mbase, MUSB_POWER,
 168                                 power | MUSB_POWER_RESET);
 169
 170                 musb->port1_status |= USB_PORT_STAT_RESET;
 171                 musb->port1_status &= ~USB_PORT_STAT_ENABLE;
 172                 schedule_delayed_work(&musb->deassert_reset_work,
 173                                       msecs_to_jiffies(50));
 174         } else {
 175                 musb_dbg(musb, "root port reset stopped");
 176                 musb_platform_pre_root_reset_end(musb);
 177                 musb_writeb(mbase, MUSB_POWER,
 178                                 power & ~MUSB_POWER_RESET);
 179                 musb_platform_post_root_reset_end(musb);
 180
 181                 power = musb_readb(mbase, MUSB_POWER);
 182                 if (power & MUSB_POWER_HSMODE) {
 183                         musb_dbg(musb, "high-speed device connected");
 184                         musb->port1_status |= USB_PORT_STAT_HIGH_SPEED;
 185                 }
 186
 187                 musb->port1_status &= ~USB_PORT_STAT_RESET;
 188                 musb->port1_status |= USB_PORT_STAT_ENABLE
 189                                         | (USB_PORT_STAT_C_RESET << 16)
 190                                         | (USB_PORT_STAT_C_ENABLE << 16);
 191                 usb_hcd_poll_rh_status(musb->hcd);
 192
 193                 musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
 194         }
 195 }
 196
 197 void musb_root_disconnect(struct musb *musb)
 198 {
 199         struct usb_otg  *otg = musb->xceiv->otg;
 200
 201         musb->port1_status = USB_PORT_STAT_POWER
 202                         | (USB_PORT_STAT_C_CONNECTION << 16);
 203
 204         usb_hcd_poll_rh_status(musb->hcd);
 205         musb->is_active = 0;
 206
 207         switch (musb->xceiv->otg->state) {
 208         case OTG_STATE_A_SUSPEND:
 209                 if (otg->host->b_hnp_enable) {
 210                         musb->xceiv->otg->state = OTG_STATE_A_PERIPHERAL;
 211                         musb->g.is_a_peripheral = 1;
 212                         break;
 213                 }
 214                 fallthrough;
 215         case OTG_STATE_A_HOST:
 216                 musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
 217                 musb->is_active = 0;
 218                 break;
 219         case OTG_STATE_A_WAIT_VFALL:
 220                 musb->xceiv->otg->state = OTG_STATE_B_IDLE;
 221                 break;
 222         default:
 223                 musb_dbg(musb, "host disconnect (%s)",
 224                         usb_otg_state_string(musb->xceiv->otg->state));
 225         }
 226 }
 227 EXPORT_SYMBOL_GPL(musb_root_disconnect);
 228
 229
 230 /*---------------------------------------------------------------------*/
 231
 232 /* Caller may or may not hold musb->lock */
 233 int musb_hub_status_data(struct usb_hcd *hcd, char *buf)
 234 {
 235         struct musb     *musb = hcd_to_musb(hcd);
 236         int             retval = 0;
 237
 238         /* called in_irq() via usb_hcd_poll_rh_status() */
 239         if (musb->port1_status & 0xffff0000) {
 240                 *buf = 0x02;
 241                 retval = 1;
 242         }
 243         return retval;
 244 }
 245
 246 static int musb_has_gadget(struct musb *musb)
 247 {
 248         /*
 249          * In host-only mode we start a connection right away. In OTG mode
 250          * we have to wait until we loaded a gadget. We don't really need a
 251          * gadget if we operate as a host but we should not start a session
 252          * as a device without a gadget or else we explode.
 253          */
 254 #ifdef CONFIG_USB_MUSB_HOST
 255         return 1;
 256 #else
 257         return musb->port_mode == MUSB_HOST;
 258 #endif
 259 }
 260
 261 int musb_hub_control(
 262         struct usb_hcd  *hcd,
 263         u16             typeReq,
 264         u16             wValue,
 265         u16             wIndex,
 266         char            *buf,
 267         u16             wLength)
 268 {
 269         struct musb     *musb = hcd_to_musb(hcd);
 270         u32             temp;
 271         int             retval = 0;
 272         unsigned long   flags;
 273         bool            start_musb = false;
 274
 275         spin_lock_irqsave(&musb->lock, flags);
 276
 277         if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) {
 278                 spin_unlock_irqrestore(&musb->lock, flags);
 279                 return -ESHUTDOWN;
 280         }
 281
 282         /* hub features:  always zero, setting is a NOP
 283          * port features: reported, sometimes updated when host is active
 284          * no indicators
 285          */
 286         switch (typeReq) {
 287         case ClearHubFeature:
 288         case SetHubFeature:
 289                 switch (wValue) {
 290                 case C_HUB_OVER_CURRENT:
 291                 case C_HUB_LOCAL_POWER:
 292                         break;
 293                 default:
 294                         goto error;
 295                 }
 296                 break;
 297         case ClearPortFeature:
 298                 if ((wIndex & 0xff) != 1)
 299                         goto error;
 300
 301                 switch (wValue) {
 302                 case USB_PORT_FEAT_ENABLE:
 303                         break;
 304                 case USB_PORT_FEAT_SUSPEND:
 305                         musb_port_suspend(musb, false);
 306                         break;
 307                 case USB_PORT_FEAT_POWER:
 308                         if (!hcd->self.is_b_host)
 309                                 musb_platform_set_vbus(musb, 0);
 310                         break;
 311                 case USB_PORT_FEAT_C_CONNECTION:
 312                 case USB_PORT_FEAT_C_ENABLE:
 313                 case USB_PORT_FEAT_C_OVER_CURRENT:
 314                 case USB_PORT_FEAT_C_RESET:
 315                 case USB_PORT_FEAT_C_SUSPEND:
 316                         break;
 317                 default:
 318                         goto error;
 319                 }
 320                 musb_dbg(musb, "clear feature %d", wValue);
 321                 musb->port1_status &= ~(1 << wValue);
 322                 break;
 323         case GetHubDescriptor:
 324                 {
 325                 struct usb_hub_descriptor *desc = (void *)buf;
 326
 327                 desc->bDescLength = 9;
 328                 desc->bDescriptorType = USB_DT_HUB;
 329                 desc->bNbrPorts = 1;
 330                 desc->wHubCharacteristics = cpu_to_le16(
 331                         HUB_CHAR_INDV_PORT_LPSM /* per-port power switching */
 332                         | HUB_CHAR_NO_OCPM      /* no overcurrent reporting */
 333                         );
 334                 desc->bPwrOn2PwrGood = 5;       /* msec/2 */
 335                 desc->bHubContrCurrent = 0;
 336
 337                 /* workaround bogus struct definition */
 338                 desc->u.hs.DeviceRemovable[0] = 0x02;   /* port 1 */
 339                 desc->u.hs.DeviceRemovable[1] = 0xff;
 340                 }
 341                 break;
 342         case GetHubStatus:
 343                 temp = 0;
 344                 *(__le32 *) buf = cpu_to_le32(temp);
 345                 break;
 346         case GetPortStatus:
 347                 if (wIndex != 1)
 348                         goto error;
 349
 350                 put_unaligned(cpu_to_le32(musb->port1_status
 351                                         & ~MUSB_PORT_STAT_RESUME),
 352                                 (__le32 *) buf);
 353
 354                 /* port change status is more interesting */
 355                 musb_dbg(musb, "port status %08x", musb->port1_status);
 356                 break;
 357         case SetPortFeature:
 358                 if ((wIndex & 0xff) != 1)
 359                         goto error;
 360
 361                 switch (wValue) {
 362                 case USB_PORT_FEAT_POWER:
 363                         /* NOTE: this controller has a strange state machine
 364                          * that involves "requesting sessions" according to
 365                          * magic side effects from incompletely-described
 366                          * rules about startup...
 367                          *
 368                          * This call is what really starts the host mode; be
 369                          * very careful about side effects if you reorder any
 370                          * initialization logic, e.g. for OTG, or change any
 371                          * logic relating to VBUS power-up.
 372                          */
 373                         if (!hcd->self.is_b_host && musb_has_gadget(musb))
 374                                 start_musb = true;
 375                         break;
 376                 case USB_PORT_FEAT_RESET:
 377                         musb_port_reset(musb, true);
 378                         break;
 379                 case USB_PORT_FEAT_SUSPEND:
 380                         musb_port_suspend(musb, true);
 381                         break;
 382                 case USB_PORT_FEAT_TEST:
 383                         if (unlikely(is_host_active(musb)))
 384                                 goto error;
 385
 386                         wIndex >>= 8;
 387                         switch (wIndex) {
 388                         case USB_TEST_J:
 389                                 pr_debug("USB_TEST_J\n");
 390                                 temp = MUSB_TEST_J;
 391                                 break;
 392                         case USB_TEST_K:
 393                                 pr_debug("USB_TEST_K\n");
 394                                 temp = MUSB_TEST_K;
 395                                 break;
 396                         case USB_TEST_SE0_NAK:
 397                                 pr_debug("USB_TEST_SE0_NAK\n");
 398                                 temp = MUSB_TEST_SE0_NAK;
 399                                 break;
 400                         case USB_TEST_PACKET:
 401                                 pr_debug("USB_TEST_PACKET\n");
 402                                 temp = MUSB_TEST_PACKET;
 403                                 musb_load_testpacket(musb);
 404                                 break;
 405                         case USB_TEST_FORCE_ENABLE:
 406                                 pr_debug("USB_TEST_FORCE_ENABLE\n");
 407                                 temp = MUSB_TEST_FORCE_HOST
 408                                         | MUSB_TEST_FORCE_HS;
 409
 410                                 musb_writeb(musb->mregs, MUSB_DEVCTL,
 411                                                 MUSB_DEVCTL_SESSION);
 412                                 break;
 413                         case 6:
 414                                 pr_debug("TEST_FIFO_ACCESS\n");
 415                                 temp = MUSB_TEST_FIFO_ACCESS;
 416                                 break;
 417                         default:
 418                                 goto error;
 419                         }
 420                         musb_writeb(musb->mregs, MUSB_TESTMODE, temp);
 421                         break;
 422                 default:
 423                         goto error;
 424                 }
 425                 musb_dbg(musb, "set feature %d", wValue);
 426                 musb->port1_status |= 1 << wValue;
 427                 break;
 428
 429         default:
 430 error:
 431                 /* "protocol stall" on error */
 432                 retval = -EPIPE;
 433         }
 434         spin_unlock_irqrestore(&musb->lock, flags);
 435
 436         if (start_musb)
 437                 musb_start(musb);
 438
 439         return retval;
 440 }