drivers/usb/dwc2/core_intr.c

   1 /*
   2  * core_intr.c - DesignWare HS OTG Controller common interrupt handling
   3  *
   4  * Copyright (C) 2004-2013 Synopsys, Inc.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions, and the following disclaimer,
  11  *    without modification.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. The names of the above-listed copyright holders may not be used
  16  *    to endorse or promote products derived from this software without
  17  *    specific prior written permission.
  18  *
  19  * ALTERNATIVELY, this software may be distributed under the terms of the
  20  * GNU General Public License ("GPL") as published by the Free Software
  21  * Foundation; either version 2 of the License, or (at your option) any
  22  * later version.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
  25  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  26  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  27  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  28  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  29  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  30  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  31  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  32  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  33  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  34  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  35  */
  36
  37 /*
  38  * This file contains the common interrupt handlers
  39  */
  40 #include <linux/kernel.h>
  41 #include <linux/module.h>
  42 #include <linux/moduleparam.h>
  43 #include <linux/spinlock.h>
  44 #include <linux/interrupt.h>
  45 #include <linux/dma-mapping.h>
  46 #include <linux/io.h>
  47 #include <linux/slab.h>
  48 #include <linux/usb.h>
  49
  50 #include <linux/usb/hcd.h>
  51 #include <linux/usb/ch11.h>
  52
  53 #include "core.h"
  54 #include "hcd.h"
  55
  56 static const char *dwc2_op_state_str(struct dwc2_hsotg *hsotg)
  57 {
  58         switch (hsotg->op_state) {
  59         case OTG_STATE_A_HOST:
  60                 return "a_host";
  61         case OTG_STATE_A_SUSPEND:
  62                 return "a_suspend";
  63         case OTG_STATE_A_PERIPHERAL:
  64                 return "a_peripheral";
  65         case OTG_STATE_B_PERIPHERAL:
  66                 return "b_peripheral";
  67         case OTG_STATE_B_HOST:
  68                 return "b_host";
  69         default:
  70                 return "unknown";
  71         }
  72 }
  73
  74 /**
  75  * dwc2_handle_mode_mismatch_intr() - Logs a mode mismatch warning message
  76  *
  77  * @hsotg: Programming view of DWC_otg controller
  78  */
  79 static void dwc2_handle_mode_mismatch_intr(struct dwc2_hsotg *hsotg)
  80 {
  81         dev_warn(hsotg->dev, "Mode Mismatch Interrupt: currently in %s mode\n",
  82                  dwc2_is_host_mode(hsotg) ? "Host" : "Device");
  83
  84         /* Clear interrupt */
  85         writel(GINTSTS_MODEMIS, hsotg->regs + GINTSTS);
  86 }
  87
  88 /**
  89  * dwc2_handle_otg_intr() - Handles the OTG Interrupts. It reads the OTG
  90  * Interrupt Register (GOTGINT) to determine what interrupt has occurred.
  91  *
  92  * @hsotg: Programming view of DWC_otg controller
  93  */
  94 static void dwc2_handle_otg_intr(struct dwc2_hsotg *hsotg)
  95 {
  96         u32 gotgint;
  97         u32 gotgctl;
  98         u32 gintmsk;
  99
 100         gotgint = readl(hsotg->regs + GOTGINT);
 101         gotgctl = readl(hsotg->regs + GOTGCTL);
 102         dev_dbg(hsotg->dev, "++OTG Interrupt gotgint=%0x [%s]\n", gotgint,
 103                 dwc2_op_state_str(hsotg));
 104
 105         if (gotgint & GOTGINT_SES_END_DET) {
 106                 dev_dbg(hsotg->dev,
 107                         " ++OTG Interrupt: Session End Detected++ (%s)\n",
 108                         dwc2_op_state_str(hsotg));
 109                 gotgctl = readl(hsotg->regs + GOTGCTL);
 110
 111                 if (hsotg->op_state == OTG_STATE_B_HOST) {
 112                         hsotg->op_state = OTG_STATE_B_PERIPHERAL;
 113                 } else {
 114                         /*
 115                          * If not B_HOST and Device HNP still set, HNP did
 116                          * not succeed!
 117                          */
 118                         if (gotgctl & GOTGCTL_DEVHNPEN) {
 119                                 dev_dbg(hsotg->dev, "Session End Detected\n");
 120                                 dev_err(hsotg->dev,
 121                                         "Device Not Connected/Responding!\n");
 122                         }
 123
 124                         /*
 125                          * If Session End Detected the B-Cable has been
 126                          * disconnected
 127                          */
 128                         /* Reset to a clean state */
 129                         hsotg->lx_state = DWC2_L0;
 130                 }
 131
 132                 gotgctl = readl(hsotg->regs + GOTGCTL);
 133                 gotgctl &= ~GOTGCTL_DEVHNPEN;
 134                 writel(gotgctl, hsotg->regs + GOTGCTL);
 135         }
 136
 137         if (gotgint & GOTGINT_SES_REQ_SUC_STS_CHNG) {
 138                 dev_dbg(hsotg->dev,
 139                         " ++OTG Interrupt: Session Request Success Status Change++\n");
 140                 gotgctl = readl(hsotg->regs + GOTGCTL);
 141                 if (gotgctl & GOTGCTL_SESREQSCS) {
 142                         if (hsotg->core_params->phy_type ==
 143                                         DWC2_PHY_TYPE_PARAM_FS
 144                             && hsotg->core_params->i2c_enable > 0) {
 145                                 hsotg->srp_success = 1;
 146                         } else {
 147                                 /* Clear Session Request */
 148                                 gotgctl = readl(hsotg->regs + GOTGCTL);
 149                                 gotgctl &= ~GOTGCTL_SESREQ;
 150                                 writel(gotgctl, hsotg->regs + GOTGCTL);
 151                         }
 152                 }
 153         }
 154
 155         if (gotgint & GOTGINT_HST_NEG_SUC_STS_CHNG) {
 156                 /*
 157                  * Print statements during the HNP interrupt handling
 158                  * can cause it to fail
 159                  */
 160                 gotgctl = readl(hsotg->regs + GOTGCTL);
 161                 /*
 162                  * WA for 3.00a- HW is not setting cur_mode, even sometimes
 163                  * this does not help
 164                  */
 165                 if (hsotg->hw_params.snpsid >= DWC2_CORE_REV_3_00a)
 166                         udelay(100);
 167                 if (gotgctl & GOTGCTL_HSTNEGSCS) {
 168                         if (dwc2_is_host_mode(hsotg)) {
 169                                 hsotg->op_state = OTG_STATE_B_HOST;
 170                                 /*
 171                                  * Need to disable SOF interrupt immediately.
 172                                  * When switching from device to host, the PCD
 173                                  * interrupt handler won't handle the interrupt
 174                                  * if host mode is already set. The HCD
 175                                  * interrupt handler won't get called if the
 176                                  * HCD state is HALT. This means that the
 177                                  * interrupt does not get handled and Linux
 178                                  * complains loudly.
 179                                  */
 180                                 gintmsk = readl(hsotg->regs + GINTMSK);
 181                                 gintmsk &= ~GINTSTS_SOF;
 182                                 writel(gintmsk, hsotg->regs + GINTMSK);
 183
 184                                 /*
 185                                  * Call callback function with spin lock
 186                                  * released
 187                                  */
 188                                 spin_unlock(&hsotg->lock);
 189
 190                                 /* Initialize the Core for Host mode */
 191                                 dwc2_hcd_start(hsotg);
 192                                 spin_lock(&hsotg->lock);
 193                                 hsotg->op_state = OTG_STATE_B_HOST;
 194                         }
 195                 } else {
 196                         gotgctl = readl(hsotg->regs + GOTGCTL);
 197                         gotgctl &= ~(GOTGCTL_HNPREQ | GOTGCTL_DEVHNPEN);
 198                         writel(gotgctl, hsotg->regs + GOTGCTL);
 199                         dev_dbg(hsotg->dev, "HNP Failed\n");
 200                         dev_err(hsotg->dev,
 201                                 "Device Not Connected/Responding\n");
 202                 }
 203         }
 204
 205         if (gotgint & GOTGINT_HST_NEG_DET) {
 206                 /*
 207                  * The disconnect interrupt is set at the same time as
 208                  * Host Negotiation Detected. During the mode switch all
 209                  * interrupts are cleared so the disconnect interrupt
 210                  * handler will not get executed.
 211                  */
 212                 dev_dbg(hsotg->dev,
 213                         " ++OTG Interrupt: Host Negotiation Detected++ (%s)\n",
 214                         (dwc2_is_host_mode(hsotg) ? "Host" : "Device"));
 215                 if (dwc2_is_device_mode(hsotg)) {
 216                         dev_dbg(hsotg->dev, "a_suspend->a_peripheral (%d)\n",
 217                                 hsotg->op_state);
 218                         spin_unlock(&hsotg->lock);
 219                         dwc2_hcd_disconnect(hsotg);
 220                         spin_lock(&hsotg->lock);
 221                         hsotg->op_state = OTG_STATE_A_PERIPHERAL;
 222                 } else {
 223                         /* Need to disable SOF interrupt immediately */
 224                         gintmsk = readl(hsotg->regs + GINTMSK);
 225                         gintmsk &= ~GINTSTS_SOF;
 226                         writel(gintmsk, hsotg->regs + GINTMSK);
 227                         spin_unlock(&hsotg->lock);
 228                         dwc2_hcd_start(hsotg);
 229                         spin_lock(&hsotg->lock);
 230                         hsotg->op_state = OTG_STATE_A_HOST;
 231                 }
 232         }
 233
 234         if (gotgint & GOTGINT_A_DEV_TOUT_CHG)
 235                 dev_dbg(hsotg->dev,
 236                         " ++OTG Interrupt: A-Device Timeout Change++\n");
 237         if (gotgint & GOTGINT_DBNCE_DONE)
 238                 dev_dbg(hsotg->dev, " ++OTG Interrupt: Debounce Done++\n");
 239
 240         /* Clear GOTGINT */
 241         writel(gotgint, hsotg->regs + GOTGINT);
 242 }
 243
 244 /**
 245  * dwc2_handle_conn_id_status_change_intr() - Handles the Connector ID Status
 246  * Change Interrupt
 247  *
 248  * @hsotg: Programming view of DWC_otg controller
 249  *
 250  * Reads the OTG Interrupt Register (GOTCTL) to determine whether this is a
 251  * Device to Host Mode transition or a Host to Device Mode transition. This only
 252  * occurs when the cable is connected/removed from the PHY connector.
 253  */
 254 static void dwc2_handle_conn_id_status_change_intr(struct dwc2_hsotg *hsotg)
 255 {
 256         u32 gintmsk = readl(hsotg->regs + GINTMSK);
 257
 258         /* Need to disable SOF interrupt immediately */
 259         gintmsk &= ~GINTSTS_SOF;
 260         writel(gintmsk, hsotg->regs + GINTMSK);
 261
 262         dev_dbg(hsotg->dev, " ++Connector ID Status Change Interrupt++  (%s)\n",
 263                 dwc2_is_host_mode(hsotg) ? "Host" : "Device");
 264
 265         /*
 266          * Need to schedule a work, as there are possible DELAY function calls.
 267          * Release lock before scheduling workq as it holds spinlock during
 268          * scheduling.
 269          */
 270         spin_unlock(&hsotg->lock);
 271         queue_work(hsotg->wq_otg, &hsotg->wf_otg);
 272         spin_lock(&hsotg->lock);
 273
 274         /* Clear interrupt */
 275         writel(GINTSTS_CONIDSTSCHNG, hsotg->regs + GINTSTS);
 276 }
 277
 278 /**
 279  * dwc2_handle_session_req_intr() - This interrupt indicates that a device is
 280  * initiating the Session Request Protocol to request the host to turn on bus
 281  * power so a new session can begin
 282  *
 283  * @hsotg: Programming view of DWC_otg controller
 284  *
 285  * This handler responds by turning on bus power. If the DWC_otg controller is
 286  * in low power mode, this handler brings the controller out of low power mode
 287  * before turning on bus power.
 288  */
 289 static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg)
 290 {
 291         dev_dbg(hsotg->dev, "++Session Request Interrupt++\n");
 292
 293         /* Clear interrupt */
 294         writel(GINTSTS_SESSREQINT, hsotg->regs + GINTSTS);
 295 }
 296
 297 /*
 298  * This interrupt indicates that the DWC_otg controller has detected a
 299  * resume or remote wakeup sequence. If the DWC_otg controller is in
 300  * low power mode, the handler must brings the controller out of low
 301  * power mode. The controller automatically begins resume signaling.
 302  * The handler schedules a time to stop resume signaling.
 303  */
 304 static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg)
 305 {
 306         dev_dbg(hsotg->dev, "++Resume or Remote Wakeup Detected Interrupt++\n");
 307         dev_dbg(hsotg->dev, "%s lxstate = %d\n", __func__, hsotg->lx_state);
 308
 309         if (dwc2_is_device_mode(hsotg)) {
 310                 dev_dbg(hsotg->dev, "DSTS=0x%0x\n", readl(hsotg->regs + DSTS));
 311                 if (hsotg->lx_state == DWC2_L2) {
 312                         u32 dctl = readl(hsotg->regs + DCTL);
 313
 314                         /* Clear Remote Wakeup Signaling */
 315                         dctl &= ~DCTL_RMTWKUPSIG;
 316                         writel(dctl, hsotg->regs + DCTL);
 317                 }
 318                 /* Change to L0 state */
 319                 hsotg->lx_state = DWC2_L0;
 320         } else {
 321                 if (hsotg->lx_state != DWC2_L1) {
 322                         u32 pcgcctl = readl(hsotg->regs + PCGCTL);
 323
 324                         /* Restart the Phy Clock */
 325                         pcgcctl &= ~PCGCTL_STOPPCLK;
 326                         writel(pcgcctl, hsotg->regs + PCGCTL);
 327                         mod_timer(&hsotg->wkp_timer,
 328                                   jiffies + msecs_to_jiffies(71));
 329                 } else {
 330                         /* Change to L0 state */
 331                         hsotg->lx_state = DWC2_L0;
 332                 }
 333         }
 334
 335         /* Clear interrupt */
 336         writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS);
 337 }
 338
 339 /*
 340  * This interrupt indicates that a device has been disconnected from the
 341  * root port
 342  */
 343 static void dwc2_handle_disconnect_intr(struct dwc2_hsotg *hsotg)
 344 {
 345         dev_dbg(hsotg->dev, "++Disconnect Detected Interrupt++ (%s) %s\n",
 346                 dwc2_is_host_mode(hsotg) ? "Host" : "Device",
 347                 dwc2_op_state_str(hsotg));
 348
 349         /* Change to L3 (OFF) state */
 350         hsotg->lx_state = DWC2_L3;
 351
 352         writel(GINTSTS_DISCONNINT, hsotg->regs + GINTSTS);
 353 }
 354
 355 /*
 356  * This interrupt indicates that SUSPEND state has been detected on the USB.
 357  *
 358  * For HNP the USB Suspend interrupt signals the change from "a_peripheral"
 359  * to "a_host".
 360  *
 361  * When power management is enabled the core will be put in low power mode.
 362  */
 363 static void dwc2_handle_usb_suspend_intr(struct dwc2_hsotg *hsotg)
 364 {
 365         u32 dsts;
 366
 367         dev_dbg(hsotg->dev, "USB SUSPEND\n");
 368
 369         if (dwc2_is_device_mode(hsotg)) {
 370                 /*
 371                  * Check the Device status register to determine if the Suspend
 372                  * state is active
 373                  */
 374                 dsts = readl(hsotg->regs + DSTS);
 375                 dev_dbg(hsotg->dev, "DSTS=0x%0x\n", dsts);
 376                 dev_dbg(hsotg->dev,
 377                         "DSTS.Suspend Status=%d HWCFG4.Power Optimize=%d\n",
 378                         !!(dsts & DSTS_SUSPSTS),
 379                         hsotg->hw_params.power_optimized);
 380         } else {
 381                 if (hsotg->op_state == OTG_STATE_A_PERIPHERAL) {
 382                         dev_dbg(hsotg->dev, "a_peripheral->a_host\n");
 383
 384                         /* Clear the a_peripheral flag, back to a_host */
 385                         spin_unlock(&hsotg->lock);
 386                         dwc2_hcd_start(hsotg);
 387                         spin_lock(&hsotg->lock);
 388                         hsotg->op_state = OTG_STATE_A_HOST;
 389                 }
 390         }
 391
 392         /* Change to L2 (suspend) state */
 393         hsotg->lx_state = DWC2_L2;
 394
 395         /* Clear interrupt */
 396         writel(GINTSTS_USBSUSP, hsotg->regs + GINTSTS);
 397 }
 398
 399 #define GINTMSK_COMMON  (GINTSTS_WKUPINT | GINTSTS_SESSREQINT |         \
 400                          GINTSTS_CONIDSTSCHNG | GINTSTS_OTGINT |        \
 401                          GINTSTS_MODEMIS | GINTSTS_DISCONNINT |         \
 402                          GINTSTS_USBSUSP | GINTSTS_PRTINT)
 403
 404 /*
 405  * This function returns the Core Interrupt register
 406  */
 407 static u32 dwc2_read_common_intr(struct dwc2_hsotg *hsotg)
 408 {
 409         u32 gintsts;
 410         u32 gintmsk;
 411         u32 gahbcfg;
 412         u32 gintmsk_common = GINTMSK_COMMON;
 413
 414         gintsts = readl(hsotg->regs + GINTSTS);
 415         gintmsk = readl(hsotg->regs + GINTMSK);
 416         gahbcfg = readl(hsotg->regs + GAHBCFG);
 417
 418         /* If any common interrupts set */
 419         if (gintsts & gintmsk_common)
 420                 dev_dbg(hsotg->dev, "gintsts=%08x  gintmsk=%08x\n",
 421                         gintsts, gintmsk);
 422
 423         if (gahbcfg & GAHBCFG_GLBL_INTR_EN)
 424                 return gintsts & gintmsk & gintmsk_common;
 425         else
 426                 return 0;
 427 }
 428
 429 /*
 430  * Common interrupt handler
 431  *
 432  * The common interrupts are those that occur in both Host and Device mode.
 433  * This handler handles the following interrupts:
 434  * - Mode Mismatch Interrupt
 435  * - OTG Interrupt
 436  * - Connector ID Status Change Interrupt
 437  * - Disconnect Interrupt
 438  * - Session Request Interrupt
 439  * - Resume / Remote Wakeup Detected Interrupt
 440  * - Suspend Interrupt
 441  */
 442 irqreturn_t dwc2_handle_common_intr(int irq, void *dev)
 443 {
 444         struct dwc2_hsotg *hsotg = dev;
 445         u32 gintsts;
 446         irqreturn_t retval = IRQ_NONE;
 447
 448         if (!dwc2_is_controller_alive(hsotg)) {
 449                 dev_warn(hsotg->dev, "Controller is dead\n");
 450                 goto out;
 451         }
 452
 453         spin_lock(&hsotg->lock);
 454
 455         gintsts = dwc2_read_common_intr(hsotg);
 456         if (gintsts & ~GINTSTS_PRTINT)
 457                 retval = IRQ_HANDLED;
 458
 459         if (gintsts & GINTSTS_MODEMIS)
 460                 dwc2_handle_mode_mismatch_intr(hsotg);
 461         if (gintsts & GINTSTS_OTGINT)
 462                 dwc2_handle_otg_intr(hsotg);
 463         if (gintsts & GINTSTS_CONIDSTSCHNG)
 464                 dwc2_handle_conn_id_status_change_intr(hsotg);
 465         if (gintsts & GINTSTS_DISCONNINT)
 466                 dwc2_handle_disconnect_intr(hsotg);
 467         if (gintsts & GINTSTS_SESSREQINT)
 468                 dwc2_handle_session_req_intr(hsotg);
 469         if (gintsts & GINTSTS_WKUPINT)
 470                 dwc2_handle_wakeup_detected_intr(hsotg);
 471         if (gintsts & GINTSTS_USBSUSP)
 472                 dwc2_handle_usb_suspend_intr(hsotg);
 473
 474         if (gintsts & GINTSTS_PRTINT) {
 475                 /*
 476                  * The port interrupt occurs while in device mode with HPRT0
 477                  * Port Enable/Disable
 478                  */
 479                 if (dwc2_is_device_mode(hsotg)) {
 480                         dev_dbg(hsotg->dev,
 481                                 " --Port interrupt received in Device mode--\n");
 482                         gintsts = GINTSTS_PRTINT;
 483                         writel(gintsts, hsotg->regs + GINTSTS);
 484                         retval = 1;
 485                 }
 486         }
 487
 488         spin_unlock(&hsotg->lock);
 489 out:
 490         return retval;
 491 }
 492 EXPORT_SYMBOL_GPL(dwc2_handle_common_intr);