usb/musb/musb_virthub.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * MUSB OTG driver virtual root hub support
0004  *
0005  * Copyright 2005 Mentor Graphics Corporation
0006  * Copyright (C) 2005-2006 by Texas Instruments
0007  * Copyright (C) 2006-2007 Nokia Corporation
0008  */
0009
0010 #include <linux/module.h>
0011 #include <linux/kernel.h>
0012 #include <linux/sched.h>
0013 #include <linux/errno.h>
0014 #include <linux/time.h>
0015 #include <linux/timer.h>
0016
0017 #include <asm/unaligned.h>
0018
0019 #include "musb_core.h"
0020
0021 void musb_host_finish_resume(struct work_struct *work)
0022 {
0023     struct musb *musb;
0024     unsigned long flags;
0025     u8 power;
0026
0027     musb = container_of(work, struct musb, finish_resume_work.work);
0028
0029     spin_lock_irqsave(&musb->lock, flags);
0030
0031     power = musb_readb(musb->mregs, MUSB_POWER);
0032     power &= ~MUSB_POWER_RESUME;
0033     musb_dbg(musb, "root port resume stopped, power %02x", power);
0034     musb_writeb(musb->mregs, MUSB_POWER, power);
0035
0036     /*
0037      * ISSUE:  DaVinci (RTL 1.300) disconnects after
0038      * resume of high speed peripherals (but not full
0039      * speed ones).
0040      */
0041     musb->is_active = 1;
0042     musb->port1_status &= ~(USB_PORT_STAT_SUSPEND | MUSB_PORT_STAT_RESUME);
0043     musb->port1_status |= USB_PORT_STAT_C_SUSPEND << 16;
0044     usb_hcd_poll_rh_status(musb->hcd);
0045     /* NOTE: it might really be A_WAIT_BCON ... */
0046     musb->xceiv->otg->state = OTG_STATE_A_HOST;
0047
0048     spin_unlock_irqrestore(&musb->lock, flags);
0049 }
0050
0051 int musb_port_suspend(struct musb *musb, bool do_suspend)
0052 {
0053     struct usb_otg  *otg = musb->xceiv->otg;
0054     u8      power;
0055     void __iomem    *mbase = musb->mregs;
0056
0057     if (!is_host_active(musb))
0058         return 0;
0059
0060     /* NOTE:  this doesn't necessarily put PHY into low power mode,
0061      * turning off its clock; that's a function of PHY integration and
0062      * MUSB_POWER_ENSUSPEND.  PHY may need a clock (sigh) to detect
0063      * SE0 changing to connect (J) or wakeup (K) states.
0064      */
0065     power = musb_readb(mbase, MUSB_POWER);
0066     if (do_suspend) {
0067         int retries = 10000;
0068
0069         if (power & MUSB_POWER_RESUME)
0070             return -EBUSY;
0071
0072         if (!(power & MUSB_POWER_SUSPENDM)) {
0073             power |= MUSB_POWER_SUSPENDM;
0074             musb_writeb(mbase, MUSB_POWER, power);
0075
0076             /* Needed for OPT A tests */
0077             power = musb_readb(mbase, MUSB_POWER);
0078             while (power & MUSB_POWER_SUSPENDM) {
0079                 power = musb_readb(mbase, MUSB_POWER);
0080                 if (retries-- < 1)
0081                     break;
0082             }
0083         }
0084
0085         musb_dbg(musb, "Root port suspended, power %02x", power);
0086
0087         musb->port1_status |= USB_PORT_STAT_SUSPEND;
0088         switch (musb->xceiv->otg->state) {
0089         case OTG_STATE_A_HOST:
0090             musb->xceiv->otg->state = OTG_STATE_A_SUSPEND;
0091             musb->is_active = otg->host->b_hnp_enable;
0092             if (musb->is_active)
0093                 mod_timer(&musb->otg_timer, jiffies
0094                     + msecs_to_jiffies(
0095                         OTG_TIME_A_AIDL_BDIS));
0096             musb_platform_try_idle(musb, 0);
0097             break;
0098         case OTG_STATE_B_HOST:
0099             musb->xceiv->otg->state = OTG_STATE_B_WAIT_ACON;
0100             musb->is_active = otg->host->b_hnp_enable;
0101             musb_platform_try_idle(musb, 0);
0102             break;
0103         default:
0104             musb_dbg(musb, "bogus rh suspend? %s",
0105                 usb_otg_state_string(musb->xceiv->otg->state));
0106         }
0107     } else if (power & MUSB_POWER_SUSPENDM) {
0108         power &= ~MUSB_POWER_SUSPENDM;
0109         power |= MUSB_POWER_RESUME;
0110         musb_writeb(mbase, MUSB_POWER, power);
0111
0112         musb_dbg(musb, "Root port resuming, power %02x", power);
0113
0114         musb->port1_status |= MUSB_PORT_STAT_RESUME;
0115         schedule_delayed_work(&musb->finish_resume_work,
0116                       msecs_to_jiffies(USB_RESUME_TIMEOUT));
0117     }
0118     return 0;
0119 }
0120
0121 void musb_port_reset(struct musb *musb, bool do_reset)
0122 {
0123     u8      power;
0124     void __iomem    *mbase = musb->mregs;
0125
0126     if (musb->xceiv->otg->state == OTG_STATE_B_IDLE) {
0127         musb_dbg(musb, "HNP: Returning from HNP; no hub reset from b_idle");
0128         musb->port1_status &= ~USB_PORT_STAT_RESET;
0129         return;
0130     }
0131
0132     if (!is_host_active(musb))
0133         return;
0134
0135     /* NOTE:  caller guarantees it will turn off the reset when
0136      * the appropriate amount of time has passed
0137      */
0138     power = musb_readb(mbase, MUSB_POWER);
0139     if (do_reset) {
0140         /*
0141          * If RESUME is set, we must make sure it stays minimum 20 ms.
0142          * Then we must clear RESUME and wait a bit to let musb start
0143          * generating SOFs. If we don't do this, OPT HS A 6.8 tests
0144          * fail with "Error! Did not receive an SOF before suspend
0145          * detected".
0146          */
0147         if (power &  MUSB_POWER_RESUME) {
0148             long remain = (unsigned long) musb->rh_timer - jiffies;
0149
0150             if (musb->rh_timer > 0 && remain > 0) {
0151                 /* take into account the minimum delay after resume */
0152                 schedule_delayed_work(
0153                     &musb->deassert_reset_work, remain);
0154                 return;
0155             }
0156
0157             musb_writeb(mbase, MUSB_POWER,
0158                     power & ~MUSB_POWER_RESUME);
0159
0160             /* Give the core 1 ms to clear MUSB_POWER_RESUME */
0161             schedule_delayed_work(&musb->deassert_reset_work,
0162                           msecs_to_jiffies(1));
0163             return;
0164         }
0165
0166         power &= 0xf0;
0167         musb_writeb(mbase, MUSB_POWER,
0168                 power | MUSB_POWER_RESET);
0169
0170         musb->port1_status |= USB_PORT_STAT_RESET;
0171         musb->port1_status &= ~USB_PORT_STAT_ENABLE;
0172         schedule_delayed_work(&musb->deassert_reset_work,
0173                       msecs_to_jiffies(50));
0174     } else {
0175         musb_dbg(musb, "root port reset stopped");
0176         musb_platform_pre_root_reset_end(musb);
0177         musb_writeb(mbase, MUSB_POWER,
0178                 power & ~MUSB_POWER_RESET);
0179         musb_platform_post_root_reset_end(musb);
0180
0181         power = musb_readb(mbase, MUSB_POWER);
0182         if (power & MUSB_POWER_HSMODE) {
0183             musb_dbg(musb, "high-speed device connected");
0184             musb->port1_status |= USB_PORT_STAT_HIGH_SPEED;
0185         }
0186
0187         musb->port1_status &= ~USB_PORT_STAT_RESET;
0188         musb->port1_status |= USB_PORT_STAT_ENABLE
0189                     | (USB_PORT_STAT_C_RESET << 16)
0190                     | (USB_PORT_STAT_C_ENABLE << 16);
0191         usb_hcd_poll_rh_status(musb->hcd);
0192
0193         musb->vbuserr_retry = VBUSERR_RETRY_COUNT;
0194     }
0195 }
0196
0197 void musb_root_disconnect(struct musb *musb)
0198 {
0199     struct usb_otg  *otg = musb->xceiv->otg;
0200
0201     musb->port1_status = USB_PORT_STAT_POWER
0202             | (USB_PORT_STAT_C_CONNECTION << 16);
0203
0204     usb_hcd_poll_rh_status(musb->hcd);
0205     musb->is_active = 0;
0206
0207     switch (musb->xceiv->otg->state) {
0208     case OTG_STATE_A_SUSPEND:
0209         if (otg->host->b_hnp_enable) {
0210             musb->xceiv->otg->state = OTG_STATE_A_PERIPHERAL;
0211             musb->g.is_a_peripheral = 1;
0212             break;
0213         }
0214         fallthrough;
0215     case OTG_STATE_A_HOST:
0216         musb->xceiv->otg->state = OTG_STATE_A_WAIT_BCON;
0217         musb->is_active = 0;
0218         break;
0219     case OTG_STATE_A_WAIT_VFALL:
0220         musb->xceiv->otg->state = OTG_STATE_B_IDLE;
0221         break;
0222     default:
0223         musb_dbg(musb, "host disconnect (%s)",
0224             usb_otg_state_string(musb->xceiv->otg->state));
0225     }
0226 }
0227 EXPORT_SYMBOL_GPL(musb_root_disconnect);
0228
0229
0230 /*---------------------------------------------------------------------*/
0231
0232 /* Caller may or may not hold musb->lock */
0233 int musb_hub_status_data(struct usb_hcd *hcd, char *buf)
0234 {
0235     struct musb *musb = hcd_to_musb(hcd);
0236     int     retval = 0;
0237
0238     /* called in_irq() via usb_hcd_poll_rh_status() */
0239     if (musb->port1_status & 0xffff0000) {
0240         *buf = 0x02;
0241         retval = 1;
0242     }
0243     return retval;
0244 }
0245
0246 static int musb_has_gadget(struct musb *musb)
0247 {
0248     /*
0249      * In host-only mode we start a connection right away. In OTG mode
0250      * we have to wait until we loaded a gadget. We don't really need a
0251      * gadget if we operate as a host but we should not start a session
0252      * as a device without a gadget or else we explode.
0253      */
0254 #ifdef CONFIG_USB_MUSB_HOST
0255     return 1;
0256 #else
0257     return musb->port_mode == MUSB_HOST;
0258 #endif
0259 }
0260
0261 int musb_hub_control(
0262     struct usb_hcd  *hcd,
0263     u16     typeReq,
0264     u16     wValue,
0265     u16     wIndex,
0266     char        *buf,
0267     u16     wLength)
0268 {
0269     struct musb *musb = hcd_to_musb(hcd);
0270     u32     temp;
0271     int     retval = 0;
0272     unsigned long   flags;
0273     bool        start_musb = false;
0274
0275     spin_lock_irqsave(&musb->lock, flags);
0276
0277     if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) {
0278         spin_unlock_irqrestore(&musb->lock, flags);
0279         return -ESHUTDOWN;
0280     }
0281
0282     /* hub features:  always zero, setting is a NOP
0283      * port features: reported, sometimes updated when host is active
0284      * no indicators
0285      */
0286     switch (typeReq) {
0287     case ClearHubFeature:
0288     case SetHubFeature:
0289         switch (wValue) {
0290         case C_HUB_OVER_CURRENT:
0291         case C_HUB_LOCAL_POWER:
0292             break;
0293         default:
0294             goto error;
0295         }
0296         break;
0297     case ClearPortFeature:
0298         if ((wIndex & 0xff) != 1)
0299             goto error;
0300
0301         switch (wValue) {
0302         case USB_PORT_FEAT_ENABLE:
0303             break;
0304         case USB_PORT_FEAT_SUSPEND:
0305             musb_port_suspend(musb, false);
0306             break;
0307         case USB_PORT_FEAT_POWER:
0308             if (!hcd->self.is_b_host)
0309                 musb_platform_set_vbus(musb, 0);
0310             break;
0311         case USB_PORT_FEAT_C_CONNECTION:
0312         case USB_PORT_FEAT_C_ENABLE:
0313         case USB_PORT_FEAT_C_OVER_CURRENT:
0314         case USB_PORT_FEAT_C_RESET:
0315         case USB_PORT_FEAT_C_SUSPEND:
0316             break;
0317         default:
0318             goto error;
0319         }
0320         musb_dbg(musb, "clear feature %d", wValue);
0321         musb->port1_status &= ~(1 << wValue);
0322         break;
0323     case GetHubDescriptor:
0324         {
0325         struct usb_hub_descriptor *desc = (void *)buf;
0326
0327         desc->bDescLength = 9;
0328         desc->bDescriptorType = USB_DT_HUB;
0329         desc->bNbrPorts = 1;
0330         desc->wHubCharacteristics = cpu_to_le16(
0331             HUB_CHAR_INDV_PORT_LPSM /* per-port power switching */
0332             | HUB_CHAR_NO_OCPM  /* no overcurrent reporting */
0333             );
0334         desc->bPwrOn2PwrGood = 5;   /* msec/2 */
0335         desc->bHubContrCurrent = 0;
0336
0337         /* workaround bogus struct definition */
0338         desc->u.hs.DeviceRemovable[0] = 0x02;   /* port 1 */
0339         desc->u.hs.DeviceRemovable[1] = 0xff;
0340         }
0341         break;
0342     case GetHubStatus:
0343         temp = 0;
0344         *(__le32 *) buf = cpu_to_le32(temp);
0345         break;
0346     case GetPortStatus:
0347         if (wIndex != 1)
0348             goto error;
0349
0350         put_unaligned(cpu_to_le32(musb->port1_status
0351                     & ~MUSB_PORT_STAT_RESUME),
0352                 (__le32 *) buf);
0353
0354         /* port change status is more interesting */
0355         musb_dbg(musb, "port status %08x", musb->port1_status);
0356         break;
0357     case SetPortFeature:
0358         if ((wIndex & 0xff) != 1)
0359             goto error;
0360
0361         switch (wValue) {
0362         case USB_PORT_FEAT_POWER:
0363             /* NOTE: this controller has a strange state machine
0364              * that involves "requesting sessions" according to
0365              * magic side effects from incompletely-described
0366              * rules about startup...
0367              *
0368              * This call is what really starts the host mode; be
0369              * very careful about side effects if you reorder any
0370              * initialization logic, e.g. for OTG, or change any
0371              * logic relating to VBUS power-up.
0372              */
0373             if (!hcd->self.is_b_host && musb_has_gadget(musb))
0374                 start_musb = true;
0375             break;
0376         case USB_PORT_FEAT_RESET:
0377             musb_port_reset(musb, true);
0378             break;
0379         case USB_PORT_FEAT_SUSPEND:
0380             musb_port_suspend(musb, true);
0381             break;
0382         case USB_PORT_FEAT_TEST:
0383             if (unlikely(is_host_active(musb)))
0384                 goto error;
0385
0386             wIndex >>= 8;
0387             switch (wIndex) {
0388             case USB_TEST_J:
0389                 pr_debug("USB_TEST_J\n");
0390                 temp = MUSB_TEST_J;
0391                 break;
0392             case USB_TEST_K:
0393                 pr_debug("USB_TEST_K\n");
0394                 temp = MUSB_TEST_K;
0395                 break;
0396             case USB_TEST_SE0_NAK:
0397                 pr_debug("USB_TEST_SE0_NAK\n");
0398                 temp = MUSB_TEST_SE0_NAK;
0399                 break;
0400             case USB_TEST_PACKET:
0401                 pr_debug("USB_TEST_PACKET\n");
0402                 temp = MUSB_TEST_PACKET;
0403                 musb_load_testpacket(musb);
0404                 break;
0405             case USB_TEST_FORCE_ENABLE:
0406                 pr_debug("USB_TEST_FORCE_ENABLE\n");
0407                 temp = MUSB_TEST_FORCE_HOST
0408                     | MUSB_TEST_FORCE_HS;
0409
0410                 musb_writeb(musb->mregs, MUSB_DEVCTL,
0411                         MUSB_DEVCTL_SESSION);
0412                 break;
0413             case 6:
0414                 pr_debug("TEST_FIFO_ACCESS\n");
0415                 temp = MUSB_TEST_FIFO_ACCESS;
0416                 break;
0417             default:
0418                 goto error;
0419             }
0420             musb_writeb(musb->mregs, MUSB_TESTMODE, temp);
0421             break;
0422         default:
0423             goto error;
0424         }
0425         musb_dbg(musb, "set feature %d", wValue);
0426         musb->port1_status |= 1 << wValue;
0427         break;
0428
0429     default:
0430 error:
0431         /* "protocol stall" on error */
0432         retval = -EPIPE;
0433     }
0434     spin_unlock_irqrestore(&musb->lock, flags);
0435
0436     if (start_musb)
0437         musb_start(musb);
0438
0439     return retval;
0440 }