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 void 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;
  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                 power &= ~MUSB_POWER_RESUME;
  70                 power |= MUSB_POWER_SUSPENDM;
  71                 musb_writeb(mbase, MUSB_POWER, power);
  72
  73                 /* Needed for OPT A tests */
  74                 power = musb_readb(mbase, MUSB_POWER);
  75                 while (power & MUSB_POWER_SUSPENDM) {
  76                         power = musb_readb(mbase, MUSB_POWER);
  77                         if (retries-- < 1)
  78                                 break;
  79                 }
  80
  81                 musb_dbg(musb, "Root port suspended, power %02x", power);
  82
  83                 musb->port1_status |= USB_PORT_STAT_SUSPEND;
  84                 switch (musb->xceiv->otg->state) {
  85                 case OTG_STATE_A_HOST:
  86                         musb->xceiv->otg->state = OTG_STATE_A_SUSPEND;
  87                         musb->is_active = otg->host->b_hnp_enable;
  88                         if (musb->is_active)
  89                                 mod_timer(&musb->otg_timer, jiffies
  90                                         + msecs_to_jiffies(
  91                                                 OTG_TIME_A_AIDL_BDIS));
  92                         musb_platform_try_idle(musb, 0);
  93                         break;
  94                 case OTG_STATE_B_HOST:
  95                         musb->xceiv->otg->state = OTG_STATE_B_WAIT_ACON;
  96                         musb->is_active = otg->host->b_hnp_enable;
  97                         musb_platform_try_idle(musb, 0);
  98                         break;
  99                 default:
 100                         musb_dbg(musb, "bogus rh suspend? %s",
 101                                 usb_otg_state_string(musb->xceiv->otg->state));
 102                 }
 103         } else if (power & MUSB_POWER_SUSPENDM) {
 104                 power &= ~MUSB_POWER_SUSPENDM;
 105                 power |= MUSB_POWER_RESUME;
 106                 musb_writeb(mbase, MUSB_POWER, power);
 107
 108                 musb_dbg(musb, "Root port resuming, power %02x", power);
 109
 110                 musb->port1_status |= MUSB_PORT_STAT_RESUME;
 111                 schedule_delayed_work(&musb->finish_resume_work,
 112                                       msecs_to_jiffies(USB_RESUME_TIMEOUT));
 113         }
 114 }
 115
 116 void musb_port_reset(struct musb *musb, bool do_reset)
 117 {
 118         u8              power;
 119         void __iomem    *mbase = musb->mregs;
 120
 121         if (musb->xceiv->otg->state == OTG_STATE_B_IDLE) {
 122                 musb_dbg(musb, "HNP: Returning from HNP; no hub reset from b_idle");
 123                 musb->port1_status &= ~USB_PORT_STAT_RESET;
 124                 return;
 125         }
 126
 127         if (!is_host_active(musb))
 128                 return;
 129
 130         /* NOTE:  caller guarantees it will turn off the reset when
 131          * the appropriate amount of time has passed
 132          */
 133         power = musb_readb(mbase, MUSB_POWER);
 134         if (do_reset) {
 135                 /*
 136                  * If RESUME is set, we must make sure it stays minimum 20 ms.
 137                  * Then we must clear RESUME and wait a bit to let musb start
 138                  * generating SOFs. If we don't do this, OPT HS A 6.8 tests
 139                  * fail with "Error! Did not receive an SOF before suspend
 140                  * detected".
 141                  */
 142                 if (power &  MUSB_POWER_RESUME) {
 143                         long remain = (unsigned long) musb->rh_timer - jiffies;
 144
 145                         if (musb->rh_timer > 0 && remain > 0) {
 146                                 /* take into account the minimum delay after resume */
 147                                 schedule_delayed_work(
 148                                         &musb->deassert_reset_work, remain);
 149                                 return;
 150                         }
 151
 152                         musb_writeb(mbase, MUSB_POWER,
 153                                     power & ~MUSB_POWER_RESUME);
 154
 155                         /* Give the core 1 ms to clear MUSB_POWER_RESUME */
 156                         schedule_delayed_work(&musb->deassert_reset_work,
 157                                               msecs_to_jiffies(1));
 158                         return;
 159                 }
 160
 161                 power &= 0xf0;
 162                 musb_writeb(mbase, MUSB_POWER,
 163                                 power | MUSB_POWER_RESET);
 164
 165                 musb->port1_status |= USB_PORT_STAT_RESET;
 166                 musb->port1_status &= ~USB_PORT_STAT_ENABLE;
 167                 schedule_delayed_work(&musb->deassert_reset_work,
 168                                       msecs_to_jiffies(50));
 169         } else {
 170                 musb_dbg(musb, "root port reset stopped");
 171                 musb_platform_pre_root_reset_end(musb);
 172                 musb_writeb(mbase, MUSB_POWER,
 173                                 power & ~MUSB_POWER_RESET);
 174                 musb_platform_post_root_reset_end(musb);
 175
 176                 power = musb_readb(mbase, MUSB_POWER);
 177                 if (power & MUSB_POWER_HSMODE) {
 178                         musb_dbg(musb, "high-speed device connected");
 179                         musb->port1_status |= USB_PORT_STAT_HIGH_SPEED;
 180                 }
 181
 182                 musb->port1_status &= ~USB_PORT_STAT_RESET;
 183                 musb->port1_status |= USB_PORT_STAT_ENABLE
 184                                         | (USB_PORT_STAT_C_RESET << 16)
 185                                         | (USB_PORT_STAT_C_ENABLE << 16);
 186                 usb_hcd_poll_rh_status(musb->hcd);
 187
 188                 musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
 189         }
 190 }
 191
 192 void musb_root_disconnect(struct musb *musb)
 193 {
 194         struct usb_otg  *otg = musb->xceiv->otg;
 195
 196         musb->port1_status = USB_PORT_STAT_POWER
 197                         | (USB_PORT_STAT_C_CONNECTION << 16);
 198
 199         usb_hcd_poll_rh_status(musb->hcd);
 200         musb->is_active = 0;
 201
 202         switch (musb->xceiv->otg->state) {
 203         case OTG_STATE_A_SUSPEND:
 204                 if (otg->host->b_hnp_enable) {
 205                         musb->xceiv->otg->state = OTG_STATE_A_PERIPHERAL;
 206                         musb->g.is_a_peripheral = 1;
 207                         break;
 208                 }
 209                 /* FALLTHROUGH */
 210         case OTG_STATE_A_HOST:
 211                 musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
 212                 musb->is_active = 0;
 213                 break;
 214         case OTG_STATE_A_WAIT_VFALL:
 215                 musb->xceiv->otg->state = OTG_STATE_B_IDLE;
 216                 break;
 217         default:
 218                 musb_dbg(musb, "host disconnect (%s)",
 219                         usb_otg_state_string(musb->xceiv->otg->state));
 220         }
 221 }
 222 EXPORT_SYMBOL_GPL(musb_root_disconnect);
 223
 224
 225 /*---------------------------------------------------------------------*/
 226
 227 /* Caller may or may not hold musb->lock */
 228 int musb_hub_status_data(struct usb_hcd *hcd, char *buf)
 229 {
 230         struct musb     *musb = hcd_to_musb(hcd);
 231         int             retval = 0;
 232
 233         /* called in_irq() via usb_hcd_poll_rh_status() */
 234         if (musb->port1_status & 0xffff0000) {
 235                 *buf = 0x02;
 236                 retval = 1;
 237         }
 238         return retval;
 239 }
 240
 241 static int musb_has_gadget(struct musb *musb)
 242 {
 243         /*
 244          * In host-only mode we start a connection right away. In OTG mode
 245          * we have to wait until we loaded a gadget. We don't really need a
 246          * gadget if we operate as a host but we should not start a session
 247          * as a device without a gadget or else we explode.
 248          */
 249 #ifdef CONFIG_USB_MUSB_HOST
 250         return 1;
 251 #else
 252         return musb->port_mode == MUSB_PORT_MODE_HOST;
 253 #endif
 254 }
 255
 256 int musb_hub_control(
 257         struct usb_hcd  *hcd,
 258         u16             typeReq,
 259         u16             wValue,
 260         u16             wIndex,
 261         char            *buf,
 262         u16             wLength)
 263 {
 264         struct musb     *musb = hcd_to_musb(hcd);
 265         u32             temp;
 266         int             retval = 0;
 267         unsigned long   flags;
 268         bool            start_musb = false;
 269
 270         spin_lock_irqsave(&musb->lock, flags);
 271
 272         if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) {
 273                 spin_unlock_irqrestore(&musb->lock, flags);
 274                 return -ESHUTDOWN;
 275         }
 276
 277         /* hub features:  always zero, setting is a NOP
 278          * port features: reported, sometimes updated when host is active
 279          * no indicators
 280          */
 281         switch (typeReq) {
 282         case ClearHubFeature:
 283         case SetHubFeature:
 284                 switch (wValue) {
 285                 case C_HUB_OVER_CURRENT:
 286                 case C_HUB_LOCAL_POWER:
 287                         break;
 288                 default:
 289                         goto error;
 290                 }
 291                 break;
 292         case ClearPortFeature:
 293                 if ((wIndex & 0xff) != 1)
 294                         goto error;
 295
 296                 switch (wValue) {
 297                 case USB_PORT_FEAT_ENABLE:
 298                         break;
 299                 case USB_PORT_FEAT_SUSPEND:
 300                         musb_port_suspend(musb, false);
 301                         break;
 302                 case USB_PORT_FEAT_POWER:
 303                         if (!hcd->self.is_b_host)
 304                                 musb_platform_set_vbus(musb, 0);
 305                         break;
 306                 case USB_PORT_FEAT_C_CONNECTION:
 307                 case USB_PORT_FEAT_C_ENABLE:
 308                 case USB_PORT_FEAT_C_OVER_CURRENT:
 309                 case USB_PORT_FEAT_C_RESET:
 310                 case USB_PORT_FEAT_C_SUSPEND:
 311                         break;
 312                 default:
 313                         goto error;
 314                 }
 315                 musb_dbg(musb, "clear feature %d", wValue);
 316                 musb->port1_status &= ~(1 << wValue);
 317                 break;
 318         case GetHubDescriptor:
 319                 {
 320                 struct usb_hub_descriptor *desc = (void *)buf;
 321
 322                 desc->bDescLength = 9;
 323                 desc->bDescriptorType = USB_DT_HUB;
 324                 desc->bNbrPorts = 1;
 325                 desc->wHubCharacteristics = cpu_to_le16(
 326                         HUB_CHAR_INDV_PORT_LPSM /* per-port power switching */
 327                         | HUB_CHAR_NO_OCPM      /* no overcurrent reporting */
 328                         );
 329                 desc->bPwrOn2PwrGood = 5;       /* msec/2 */
 330                 desc->bHubContrCurrent = 0;
 331
 332                 /* workaround bogus struct definition */
 333                 desc->u.hs.DeviceRemovable[0] = 0x02;   /* port 1 */
 334                 desc->u.hs.DeviceRemovable[1] = 0xff;
 335                 }
 336                 break;
 337         case GetHubStatus:
 338                 temp = 0;
 339                 *(__le32 *) buf = cpu_to_le32(temp);
 340                 break;
 341         case GetPortStatus:
 342                 if (wIndex != 1)
 343                         goto error;
 344
 345                 put_unaligned(cpu_to_le32(musb->port1_status
 346                                         & ~MUSB_PORT_STAT_RESUME),
 347                                 (__le32 *) buf);
 348
 349                 /* port change status is more interesting */
 350                 musb_dbg(musb, "port status %08x", musb->port1_status);
 351                 break;
 352         case SetPortFeature:
 353                 if ((wIndex & 0xff) != 1)
 354                         goto error;
 355
 356                 switch (wValue) {
 357                 case USB_PORT_FEAT_POWER:
 358                         /* NOTE: this controller has a strange state machine
 359                          * that involves "requesting sessions" according to
 360                          * magic side effects from incompletely-described
 361                          * rules about startup...
 362                          *
 363                          * This call is what really starts the host mode; be
 364                          * very careful about side effects if you reorder any
 365                          * initialization logic, e.g. for OTG, or change any
 366                          * logic relating to VBUS power-up.
 367                          */
 368                         if (!hcd->self.is_b_host && musb_has_gadget(musb))
 369                                 start_musb = true;
 370                         break;
 371                 case USB_PORT_FEAT_RESET:
 372                         musb_port_reset(musb, true);
 373                         break;
 374                 case USB_PORT_FEAT_SUSPEND:
 375                         musb_port_suspend(musb, true);
 376                         break;
 377                 case USB_PORT_FEAT_TEST:
 378                         if (unlikely(is_host_active(musb)))
 379                                 goto error;
 380
 381                         wIndex >>= 8;
 382                         switch (wIndex) {
 383                         case 1:
 384                                 pr_debug("TEST_J\n");
 385                                 temp = MUSB_TEST_J;
 386                                 break;
 387                         case 2:
 388                                 pr_debug("TEST_K\n");
 389                                 temp = MUSB_TEST_K;
 390                                 break;
 391                         case 3:
 392                                 pr_debug("TEST_SE0_NAK\n");
 393                                 temp = MUSB_TEST_SE0_NAK;
 394                                 break;
 395                         case 4:
 396                                 pr_debug("TEST_PACKET\n");
 397                                 temp = MUSB_TEST_PACKET;
 398                                 musb_load_testpacket(musb);
 399                                 break;
 400                         case 5:
 401                                 pr_debug("TEST_FORCE_ENABLE\n");
 402                                 temp = MUSB_TEST_FORCE_HOST
 403                                         | MUSB_TEST_FORCE_HS;
 404
 405                                 musb_writeb(musb->mregs, MUSB_DEVCTL,
 406                                                 MUSB_DEVCTL_SESSION);
 407                                 break;
 408                         case 6:
 409                                 pr_debug("TEST_FIFO_ACCESS\n");
 410                                 temp = MUSB_TEST_FIFO_ACCESS;
 411                                 break;
 412                         default:
 413                                 goto error;
 414                         }
 415                         musb_writeb(musb->mregs, MUSB_TESTMODE, temp);
 416                         break;
 417                 default:
 418                         goto error;
 419                 }
 420                 musb_dbg(musb, "set feature %d", wValue);
 421                 musb->port1_status |= 1 << wValue;
 422                 break;
 423
 424         default:
 425 error:
 426                 /* "protocol stall" on error */
 427                 retval = -EPIPE;
 428         }
 429         spin_unlock_irqrestore(&musb->lock, flags);
 430
 431         if (start_musb)
 432                 musb_start(musb);
 433
 434         return retval;
 435 }