kernel/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_usb_port_intr - handles OTG PRTINT interrupts.
  76  * When the PRTINT interrupt fires, there are certain status bits in the Host
  77  * Port that needs to get cleared.
  78  *
  79  * @hsotg: Programming view of DWC_otg controller
  80  */
  81 static void dwc2_handle_usb_port_intr(struct dwc2_hsotg *hsotg)
  82 {
  83         u32 hprt0 = readl(hsotg->regs + HPRT0);
  84
  85         if (hprt0 & HPRT0_ENACHG) {
  86                 hprt0 &= ~HPRT0_ENA;
  87                 writel(hprt0, hsotg->regs + HPRT0);
  88         }
  89
  90         /* Clear interrupt */
  91         writel(GINTSTS_PRTINT, hsotg->regs + GINTSTS);
  92 }
  93
  94 /**
  95  * dwc2_handle_mode_mismatch_intr() - Logs a mode mismatch warning message
  96  *
  97  * @hsotg: Programming view of DWC_otg controller
  98  */
  99 static void dwc2_handle_mode_mismatch_intr(struct dwc2_hsotg *hsotg)
 100 {
 101         dev_warn(hsotg->dev, "Mode Mismatch Interrupt: currently in %s mode\n",
 102                  dwc2_is_host_mode(hsotg) ? "Host" : "Device");
 103
 104         /* Clear interrupt */
 105         writel(GINTSTS_MODEMIS, hsotg->regs + GINTSTS);
 106 }
 107
 108 /**
 109  * dwc2_handle_otg_intr() - Handles the OTG Interrupts. It reads the OTG
 110  * Interrupt Register (GOTGINT) to determine what interrupt has occurred.
 111  *
 112  * @hsotg: Programming view of DWC_otg controller
 113  */
 114 static void dwc2_handle_otg_intr(struct dwc2_hsotg *hsotg)
 115 {
 116         u32 gotgint;
 117         u32 gotgctl;
 118         u32 gintmsk;
 119
 120         gotgint = readl(hsotg->regs + GOTGINT);
 121         gotgctl = readl(hsotg->regs + GOTGCTL);
 122         dev_dbg(hsotg->dev, "++OTG Interrupt gotgint=%0x [%s]\n", gotgint,
 123                 dwc2_op_state_str(hsotg));
 124
 125         if (gotgint & GOTGINT_SES_END_DET) {
 126                 dev_dbg(hsotg->dev,
 127                         " ++OTG Interrupt: Session End Detected++ (%s)\n",
 128                         dwc2_op_state_str(hsotg));
 129                 gotgctl = readl(hsotg->regs + GOTGCTL);
 130
 131                 if (dwc2_is_device_mode(hsotg))
 132                         s3c_hsotg_disconnect(hsotg);
 133
 134                 if (hsotg->op_state == OTG_STATE_B_HOST) {
 135                         hsotg->op_state = OTG_STATE_B_PERIPHERAL;
 136                 } else {
 137                         /*
 138                          * If not B_HOST and Device HNP still set, HNP did
 139                          * not succeed!
 140                          */
 141                         if (gotgctl & GOTGCTL_DEVHNPEN) {
 142                                 dev_dbg(hsotg->dev, "Session End Detected\n");
 143                                 dev_err(hsotg->dev,
 144                                         "Device Not Connected/Responding!\n");
 145                         }
 146
 147                         /*
 148                          * If Session End Detected the B-Cable has been
 149                          * disconnected
 150                          */
 151                         /* Reset to a clean state */
 152                         hsotg->lx_state = DWC2_L0;
 153                 }
 154
 155                 gotgctl = readl(hsotg->regs + GOTGCTL);
 156                 gotgctl &= ~GOTGCTL_DEVHNPEN;
 157                 writel(gotgctl, hsotg->regs + GOTGCTL);
 158         }
 159
 160         if (gotgint & GOTGINT_SES_REQ_SUC_STS_CHNG) {
 161                 dev_dbg(hsotg->dev,
 162                         " ++OTG Interrupt: Session Request Success Status Change++\n");
 163                 gotgctl = readl(hsotg->regs + GOTGCTL);
 164                 if (gotgctl & GOTGCTL_SESREQSCS) {
 165                         if (hsotg->core_params->phy_type ==
 166                                         DWC2_PHY_TYPE_PARAM_FS
 167                             && hsotg->core_params->i2c_enable > 0) {
 168                                 hsotg->srp_success = 1;
 169                         } else {
 170                                 /* Clear Session Request */
 171                                 gotgctl = readl(hsotg->regs + GOTGCTL);
 172                                 gotgctl &= ~GOTGCTL_SESREQ;
 173                                 writel(gotgctl, hsotg->regs + GOTGCTL);
 174                         }
 175                 }
 176         }
 177
 178         if (gotgint & GOTGINT_HST_NEG_SUC_STS_CHNG) {
 179                 /*
 180                  * Print statements during the HNP interrupt handling
 181                  * can cause it to fail
 182                  */
 183                 gotgctl = readl(hsotg->regs + GOTGCTL);
 184                 /*
 185                  * WA for 3.00a- HW is not setting cur_mode, even sometimes
 186                  * this does not help
 187                  */
 188                 if (hsotg->hw_params.snpsid >= DWC2_CORE_REV_3_00a)
 189                         udelay(100);
 190                 if (gotgctl & GOTGCTL_HSTNEGSCS) {
 191                         if (dwc2_is_host_mode(hsotg)) {
 192                                 hsotg->op_state = OTG_STATE_B_HOST;
 193                                 /*
 194                                  * Need to disable SOF interrupt immediately.
 195                                  * When switching from device to host, the PCD
 196                                  * interrupt handler won't handle the interrupt
 197                                  * if host mode is already set. The HCD
 198                                  * interrupt handler won't get called if the
 199                                  * HCD state is HALT. This means that the
 200                                  * interrupt does not get handled and Linux
 201                                  * complains loudly.
 202                                  */
 203                                 gintmsk = readl(hsotg->regs + GINTMSK);
 204                                 gintmsk &= ~GINTSTS_SOF;
 205                                 writel(gintmsk, hsotg->regs + GINTMSK);
 206
 207                                 /*
 208                                  * Call callback function with spin lock
 209                                  * released
 210                                  */
 211                                 spin_unlock(&hsotg->lock);
 212
 213                                 /* Initialize the Core for Host mode */
 214                                 dwc2_hcd_start(hsotg);
 215                                 spin_lock(&hsotg->lock);
 216                                 hsotg->op_state = OTG_STATE_B_HOST;
 217                         }
 218                 } else {
 219                         gotgctl = readl(hsotg->regs + GOTGCTL);
 220                         gotgctl &= ~(GOTGCTL_HNPREQ | GOTGCTL_DEVHNPEN);
 221                         writel(gotgctl, hsotg->regs + GOTGCTL);
 222                         dev_dbg(hsotg->dev, "HNP Failed\n");
 223                         dev_err(hsotg->dev,
 224                                 "Device Not Connected/Responding\n");
 225                 }
 226         }
 227
 228         if (gotgint & GOTGINT_HST_NEG_DET) {
 229                 /*
 230                  * The disconnect interrupt is set at the same time as
 231                  * Host Negotiation Detected. During the mode switch all
 232                  * interrupts are cleared so the disconnect interrupt
 233                  * handler will not get executed.
 234                  */
 235                 dev_dbg(hsotg->dev,
 236                         " ++OTG Interrupt: Host Negotiation Detected++ (%s)\n",
 237                         (dwc2_is_host_mode(hsotg) ? "Host" : "Device"));
 238                 if (dwc2_is_device_mode(hsotg)) {
 239                         dev_dbg(hsotg->dev, "a_suspend->a_peripheral (%d)\n",
 240                                 hsotg->op_state);
 241                         spin_unlock(&hsotg->lock);
 242                         dwc2_hcd_disconnect(hsotg);
 243                         spin_lock(&hsotg->lock);
 244                         hsotg->op_state = OTG_STATE_A_PERIPHERAL;
 245                 } else {
 246                         /* Need to disable SOF interrupt immediately */
 247                         gintmsk = readl(hsotg->regs + GINTMSK);
 248                         gintmsk &= ~GINTSTS_SOF;
 249                         writel(gintmsk, hsotg->regs + GINTMSK);
 250                         spin_unlock(&hsotg->lock);
 251                         dwc2_hcd_start(hsotg);
 252                         spin_lock(&hsotg->lock);
 253                         hsotg->op_state = OTG_STATE_A_HOST;
 254                 }
 255         }
 256
 257         if (gotgint & GOTGINT_A_DEV_TOUT_CHG)
 258                 dev_dbg(hsotg->dev,
 259                         " ++OTG Interrupt: A-Device Timeout Change++\n");
 260         if (gotgint & GOTGINT_DBNCE_DONE)
 261                 dev_dbg(hsotg->dev, " ++OTG Interrupt: Debounce Done++\n");
 262
 263         /* Clear GOTGINT */
 264         writel(gotgint, hsotg->regs + GOTGINT);
 265 }
 266
 267 /**
 268  * dwc2_handle_conn_id_status_change_intr() - Handles the Connector ID Status
 269  * Change Interrupt
 270  *
 271  * @hsotg: Programming view of DWC_otg controller
 272  *
 273  * Reads the OTG Interrupt Register (GOTCTL) to determine whether this is a
 274  * Device to Host Mode transition or a Host to Device Mode transition. This only
 275  * occurs when the cable is connected/removed from the PHY connector.
 276  */
 277 static void dwc2_handle_conn_id_status_change_intr(struct dwc2_hsotg *hsotg)
 278 {
 279         u32 gintmsk = readl(hsotg->regs + GINTMSK);
 280
 281         /* Need to disable SOF interrupt immediately */
 282         gintmsk &= ~GINTSTS_SOF;
 283         writel(gintmsk, hsotg->regs + GINTMSK);
 284
 285         dev_dbg(hsotg->dev, " ++Connector ID Status Change Interrupt++  (%s)\n",
 286                 dwc2_is_host_mode(hsotg) ? "Host" : "Device");
 287
 288         /*
 289          * Need to schedule a work, as there are possible DELAY function calls.
 290          * Release lock before scheduling workq as it holds spinlock during
 291          * scheduling.
 292          */
 293         if (hsotg->wq_otg) {
 294                 spin_unlock(&hsotg->lock);
 295                 queue_work(hsotg->wq_otg, &hsotg->wf_otg);
 296                 spin_lock(&hsotg->lock);
 297         }
 298
 299         /* Clear interrupt */
 300         writel(GINTSTS_CONIDSTSCHNG, hsotg->regs + GINTSTS);
 301 }
 302
 303 /**
 304  * dwc2_handle_session_req_intr() - This interrupt indicates that a device is
 305  * initiating the Session Request Protocol to request the host to turn on bus
 306  * power so a new session can begin
 307  *
 308  * @hsotg: Programming view of DWC_otg controller
 309  *
 310  * This handler responds by turning on bus power. If the DWC_otg controller is
 311  * in low power mode, this handler brings the controller out of low power mode
 312  * before turning on bus power.
 313  */
 314 static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg)
 315 {
 316         dev_dbg(hsotg->dev, "++Session Request Interrupt++\n");
 317
 318         /* Clear interrupt */
 319         writel(GINTSTS_SESSREQINT, hsotg->regs + GINTSTS);
 320
 321         /*
 322          * Report disconnect if there is any previous session established
 323          */
 324         if (dwc2_is_device_mode(hsotg))
 325                 s3c_hsotg_disconnect(hsotg);
 326 }
 327
 328 /*
 329  * This interrupt indicates that the DWC_otg controller has detected a
 330  * resume or remote wakeup sequence. If the DWC_otg controller is in
 331  * low power mode, the handler must brings the controller out of low
 332  * power mode. The controller automatically begins resume signaling.
 333  * The handler schedules a time to stop resume signaling.
 334  */
 335 static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg)
 336 {
 337         dev_dbg(hsotg->dev, "++Resume or Remote Wakeup Detected Interrupt++\n");
 338         dev_dbg(hsotg->dev, "%s lxstate = %d\n", __func__, hsotg->lx_state);
 339
 340         if (dwc2_is_device_mode(hsotg)) {
 341                 dev_dbg(hsotg->dev, "DSTS=0x%0x\n", readl(hsotg->regs + DSTS));
 342                 if (hsotg->lx_state == DWC2_L2) {
 343                         u32 dctl = readl(hsotg->regs + DCTL);
 344
 345                         /* Clear Remote Wakeup Signaling */
 346                         dctl &= ~DCTL_RMTWKUPSIG;
 347                         writel(dctl, hsotg->regs + DCTL);
 348                 }
 349                 /* Change to L0 state */
 350                 hsotg->lx_state = DWC2_L0;
 351         } else {
 352                 if (hsotg->lx_state != DWC2_L1) {
 353                         u32 pcgcctl = readl(hsotg->regs + PCGCTL);
 354
 355                         /* Restart the Phy Clock */
 356                         pcgcctl &= ~PCGCTL_STOPPCLK;
 357                         writel(pcgcctl, hsotg->regs + PCGCTL);
 358                         mod_timer(&hsotg->wkp_timer,
 359                                   jiffies + msecs_to_jiffies(71));
 360                 } else {
 361                         /* Change to L0 state */
 362                         hsotg->lx_state = DWC2_L0;
 363                 }
 364         }
 365
 366         /* Clear interrupt */
 367         writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS);
 368 }
 369
 370 /*
 371  * This interrupt indicates that a device has been disconnected from the
 372  * root port
 373  */
 374 static void dwc2_handle_disconnect_intr(struct dwc2_hsotg *hsotg)
 375 {
 376         dev_dbg(hsotg->dev, "++Disconnect Detected Interrupt++ (%s) %s\n",
 377                 dwc2_is_host_mode(hsotg) ? "Host" : "Device",
 378                 dwc2_op_state_str(hsotg));
 379
 380         if (hsotg->op_state == OTG_STATE_A_HOST)
 381                 dwc2_hcd_disconnect(hsotg);
 382
 383         /* Change to L3 (OFF) state */
 384         hsotg->lx_state = DWC2_L3;
 385
 386         writel(GINTSTS_DISCONNINT, hsotg->regs + GINTSTS);
 387 }
 388
 389 /*
 390  * This interrupt indicates that SUSPEND state has been detected on the USB.
 391  *
 392  * For HNP the USB Suspend interrupt signals the change from "a_peripheral"
 393  * to "a_host".
 394  *
 395  * When power management is enabled the core will be put in low power mode.
 396  */
 397 static void dwc2_handle_usb_suspend_intr(struct dwc2_hsotg *hsotg)
 398 {
 399         u32 dsts;
 400
 401         dev_dbg(hsotg->dev, "USB SUSPEND\n");
 402
 403         if (dwc2_is_device_mode(hsotg)) {
 404                 /*
 405                  * Check the Device status register to determine if the Suspend
 406                  * state is active
 407                  */
 408                 dsts = readl(hsotg->regs + DSTS);
 409                 dev_dbg(hsotg->dev, "DSTS=0x%0x\n", dsts);
 410                 dev_dbg(hsotg->dev,
 411                         "DSTS.Suspend Status=%d HWCFG4.Power Optimize=%d\n",
 412                         !!(dsts & DSTS_SUSPSTS),
 413                         hsotg->hw_params.power_optimized);
 414         } else {
 415                 if (hsotg->op_state == OTG_STATE_A_PERIPHERAL) {
 416                         dev_dbg(hsotg->dev, "a_peripheral->a_host\n");
 417
 418                         /* Clear the a_peripheral flag, back to a_host */
 419                         spin_unlock(&hsotg->lock);
 420                         dwc2_hcd_start(hsotg);
 421                         spin_lock(&hsotg->lock);
 422                         hsotg->op_state = OTG_STATE_A_HOST;
 423                 }
 424         }
 425
 426         /* Change to L2 (suspend) state */
 427         hsotg->lx_state = DWC2_L2;
 428
 429         /* Clear interrupt */
 430         writel(GINTSTS_USBSUSP, hsotg->regs + GINTSTS);
 431 }
 432
 433 #define GINTMSK_COMMON  (GINTSTS_WKUPINT | GINTSTS_SESSREQINT |         \
 434                          GINTSTS_CONIDSTSCHNG | GINTSTS_OTGINT |        \
 435                          GINTSTS_MODEMIS | GINTSTS_DISCONNINT |         \
 436                          GINTSTS_USBSUSP | GINTSTS_PRTINT)
 437
 438 /*
 439  * This function returns the Core Interrupt register
 440  */
 441 static u32 dwc2_read_common_intr(struct dwc2_hsotg *hsotg)
 442 {
 443         u32 gintsts;
 444         u32 gintmsk;
 445         u32 gahbcfg;
 446         u32 gintmsk_common = GINTMSK_COMMON;
 447
 448         gintsts = readl(hsotg->regs + GINTSTS);
 449         gintmsk = readl(hsotg->regs + GINTMSK);
 450         gahbcfg = readl(hsotg->regs + GAHBCFG);
 451
 452         /* If any common interrupts set */
 453         if (gintsts & gintmsk_common)
 454                 dev_dbg(hsotg->dev, "gintsts=%08x  gintmsk=%08x\n",
 455                         gintsts, gintmsk);
 456
 457         if (gahbcfg & GAHBCFG_GLBL_INTR_EN)
 458                 return gintsts & gintmsk & gintmsk_common;
 459         else
 460                 return 0;
 461 }
 462
 463 /*
 464  * Common interrupt handler
 465  *
 466  * The common interrupts are those that occur in both Host and Device mode.
 467  * This handler handles the following interrupts:
 468  * - Mode Mismatch Interrupt
 469  * - OTG Interrupt
 470  * - Connector ID Status Change Interrupt
 471  * - Disconnect Interrupt
 472  * - Session Request Interrupt
 473  * - Resume / Remote Wakeup Detected Interrupt
 474  * - Suspend Interrupt
 475  */
 476 irqreturn_t dwc2_handle_common_intr(int irq, void *dev)
 477 {
 478         struct dwc2_hsotg *hsotg = dev;
 479         u32 gintsts;
 480         irqreturn_t retval = IRQ_NONE;
 481
 482         spin_lock(&hsotg->lock);
 483
 484         if (!dwc2_is_controller_alive(hsotg)) {
 485                 dev_warn(hsotg->dev, "Controller is dead\n");
 486                 goto out;
 487         }
 488
 489         gintsts = dwc2_read_common_intr(hsotg);
 490         if (gintsts & ~GINTSTS_PRTINT)
 491                 retval = IRQ_HANDLED;
 492
 493         if (gintsts & GINTSTS_MODEMIS)
 494                 dwc2_handle_mode_mismatch_intr(hsotg);
 495         if (gintsts & GINTSTS_OTGINT)
 496                 dwc2_handle_otg_intr(hsotg);
 497         if (gintsts & GINTSTS_CONIDSTSCHNG)
 498                 dwc2_handle_conn_id_status_change_intr(hsotg);
 499         if (gintsts & GINTSTS_DISCONNINT)
 500                 dwc2_handle_disconnect_intr(hsotg);
 501         if (gintsts & GINTSTS_SESSREQINT)
 502                 dwc2_handle_session_req_intr(hsotg);
 503         if (gintsts & GINTSTS_WKUPINT)
 504                 dwc2_handle_wakeup_detected_intr(hsotg);
 505         if (gintsts & GINTSTS_USBSUSP)
 506                 dwc2_handle_usb_suspend_intr(hsotg);
 507
 508         if (gintsts & GINTSTS_PRTINT) {
 509                 /*
 510                  * The port interrupt occurs while in device mode with HPRT0
 511                  * Port Enable/Disable
 512                  */
 513                 if (dwc2_is_device_mode(hsotg)) {
 514                         dev_dbg(hsotg->dev,
 515                                 " --Port interrupt received in Device mode--\n");
 516                         dwc2_handle_usb_port_intr(hsotg);
 517                         retval = IRQ_HANDLED;
 518                 }
 519         }
 520
 521 out:
 522         spin_unlock(&hsotg->lock);
 523         return retval;
 524 }
 525 EXPORT_SYMBOL_GPL(dwc2_handle_common_intr);