Merge tag 'usb-4.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
[firefly-linux-kernel-4.4.55.git] / 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         int ret;
338         dev_dbg(hsotg->dev, "++Resume or Remote Wakeup Detected Interrupt++\n");
339         dev_dbg(hsotg->dev, "%s lxstate = %d\n", __func__, hsotg->lx_state);
340
341         if (dwc2_is_device_mode(hsotg)) {
342                 dev_dbg(hsotg->dev, "DSTS=0x%0x\n", readl(hsotg->regs + DSTS));
343                 if (hsotg->lx_state == DWC2_L2) {
344                         u32 dctl = readl(hsotg->regs + DCTL);
345
346                         /* Clear Remote Wakeup Signaling */
347                         dctl &= ~DCTL_RMTWKUPSIG;
348                         writel(dctl, hsotg->regs + DCTL);
349                         ret = dwc2_exit_hibernation(hsotg, true);
350                         if (ret && (ret != -ENOTSUPP))
351                                 dev_err(hsotg->dev, "exit hibernation failed\n");
352
353                         call_gadget(hsotg, resume);
354                 }
355                 /* Change to L0 state */
356                 hsotg->lx_state = DWC2_L0;
357         } else {
358                 if (hsotg->lx_state != DWC2_L1) {
359                         u32 pcgcctl = readl(hsotg->regs + PCGCTL);
360
361                         /* Restart the Phy Clock */
362                         pcgcctl &= ~PCGCTL_STOPPCLK;
363                         writel(pcgcctl, hsotg->regs + PCGCTL);
364                         mod_timer(&hsotg->wkp_timer,
365                                   jiffies + msecs_to_jiffies(71));
366                 } else {
367                         /* Change to L0 state */
368                         hsotg->lx_state = DWC2_L0;
369                 }
370         }
371
372         /* Clear interrupt */
373         writel(GINTSTS_WKUPINT, hsotg->regs + GINTSTS);
374 }
375
376 /*
377  * This interrupt indicates that a device has been disconnected from the
378  * root port
379  */
380 static void dwc2_handle_disconnect_intr(struct dwc2_hsotg *hsotg)
381 {
382         dev_dbg(hsotg->dev, "++Disconnect Detected Interrupt++ (%s) %s\n",
383                 dwc2_is_host_mode(hsotg) ? "Host" : "Device",
384                 dwc2_op_state_str(hsotg));
385
386         if (hsotg->op_state == OTG_STATE_A_HOST)
387                 dwc2_hcd_disconnect(hsotg);
388
389         /* Change to L3 (OFF) state */
390         hsotg->lx_state = DWC2_L3;
391
392         writel(GINTSTS_DISCONNINT, hsotg->regs + GINTSTS);
393 }
394
395 /*
396  * This interrupt indicates that SUSPEND state has been detected on the USB.
397  *
398  * For HNP the USB Suspend interrupt signals the change from "a_peripheral"
399  * to "a_host".
400  *
401  * When power management is enabled the core will be put in low power mode.
402  */
403 static void dwc2_handle_usb_suspend_intr(struct dwc2_hsotg *hsotg)
404 {
405         u32 dsts;
406         int ret;
407
408         dev_dbg(hsotg->dev, "USB SUSPEND\n");
409
410         if (dwc2_is_device_mode(hsotg)) {
411                 /*
412                  * Check the Device status register to determine if the Suspend
413                  * state is active
414                  */
415                 dsts = readl(hsotg->regs + DSTS);
416                 dev_dbg(hsotg->dev, "DSTS=0x%0x\n", dsts);
417                 dev_dbg(hsotg->dev,
418                         "DSTS.Suspend Status=%d HWCFG4.Power Optimize=%d\n",
419                         !!(dsts & DSTS_SUSPSTS),
420                         hsotg->hw_params.power_optimized);
421                 if ((dsts & DSTS_SUSPSTS) && hsotg->hw_params.power_optimized) {
422                         /* Ignore suspend request before enumeration */
423                         if (!dwc2_is_device_connected(hsotg)) {
424                                 dev_dbg(hsotg->dev,
425                                                 "ignore suspend request before enumeration\n");
426                                 goto clear_int;
427                         }
428
429                         ret = dwc2_enter_hibernation(hsotg);
430                         if (ret) {
431                                 if (ret != -ENOTSUPP)
432                                         dev_err(hsotg->dev,
433                                                         "enter hibernation failed\n");
434                                 goto skip_power_saving;
435                         }
436
437                         udelay(100);
438
439                         /* Ask phy to be suspended */
440                         if (!IS_ERR_OR_NULL(hsotg->uphy))
441                                 usb_phy_set_suspend(hsotg->uphy, true);
442 skip_power_saving:
443                         /*
444                          * Change to L2 (suspend) state before releasing
445                          * spinlock
446                          */
447                         hsotg->lx_state = DWC2_L2;
448
449                         /* Call gadget suspend callback */
450                         call_gadget(hsotg, suspend);
451                 }
452         } else {
453                 if (hsotg->op_state == OTG_STATE_A_PERIPHERAL) {
454                         dev_dbg(hsotg->dev, "a_peripheral->a_host\n");
455
456                         /* Change to L2 (suspend) state */
457                         hsotg->lx_state = DWC2_L2;
458                         /* Clear the a_peripheral flag, back to a_host */
459                         spin_unlock(&hsotg->lock);
460                         dwc2_hcd_start(hsotg);
461                         spin_lock(&hsotg->lock);
462                         hsotg->op_state = OTG_STATE_A_HOST;
463                 }
464         }
465
466 clear_int:
467         /* Clear interrupt */
468         writel(GINTSTS_USBSUSP, hsotg->regs + GINTSTS);
469 }
470
471 #define GINTMSK_COMMON  (GINTSTS_WKUPINT | GINTSTS_SESSREQINT |         \
472                          GINTSTS_CONIDSTSCHNG | GINTSTS_OTGINT |        \
473                          GINTSTS_MODEMIS | GINTSTS_DISCONNINT |         \
474                          GINTSTS_USBSUSP | GINTSTS_PRTINT)
475
476 /*
477  * This function returns the Core Interrupt register
478  */
479 static u32 dwc2_read_common_intr(struct dwc2_hsotg *hsotg)
480 {
481         u32 gintsts;
482         u32 gintmsk;
483         u32 gahbcfg;
484         u32 gintmsk_common = GINTMSK_COMMON;
485
486         gintsts = readl(hsotg->regs + GINTSTS);
487         gintmsk = readl(hsotg->regs + GINTMSK);
488         gahbcfg = readl(hsotg->regs + GAHBCFG);
489
490         /* If any common interrupts set */
491         if (gintsts & gintmsk_common)
492                 dev_dbg(hsotg->dev, "gintsts=%08x  gintmsk=%08x\n",
493                         gintsts, gintmsk);
494
495         if (gahbcfg & GAHBCFG_GLBL_INTR_EN)
496                 return gintsts & gintmsk & gintmsk_common;
497         else
498                 return 0;
499 }
500
501 /*
502  * Common interrupt handler
503  *
504  * The common interrupts are those that occur in both Host and Device mode.
505  * This handler handles the following interrupts:
506  * - Mode Mismatch Interrupt
507  * - OTG Interrupt
508  * - Connector ID Status Change Interrupt
509  * - Disconnect Interrupt
510  * - Session Request Interrupt
511  * - Resume / Remote Wakeup Detected Interrupt
512  * - Suspend Interrupt
513  */
514 irqreturn_t dwc2_handle_common_intr(int irq, void *dev)
515 {
516         struct dwc2_hsotg *hsotg = dev;
517         u32 gintsts;
518         irqreturn_t retval = IRQ_NONE;
519
520         spin_lock(&hsotg->lock);
521
522         if (!dwc2_is_controller_alive(hsotg)) {
523                 dev_warn(hsotg->dev, "Controller is dead\n");
524                 goto out;
525         }
526
527         gintsts = dwc2_read_common_intr(hsotg);
528         if (gintsts & ~GINTSTS_PRTINT)
529                 retval = IRQ_HANDLED;
530
531         if (gintsts & GINTSTS_MODEMIS)
532                 dwc2_handle_mode_mismatch_intr(hsotg);
533         if (gintsts & GINTSTS_OTGINT)
534                 dwc2_handle_otg_intr(hsotg);
535         if (gintsts & GINTSTS_CONIDSTSCHNG)
536                 dwc2_handle_conn_id_status_change_intr(hsotg);
537         if (gintsts & GINTSTS_DISCONNINT)
538                 dwc2_handle_disconnect_intr(hsotg);
539         if (gintsts & GINTSTS_SESSREQINT)
540                 dwc2_handle_session_req_intr(hsotg);
541         if (gintsts & GINTSTS_WKUPINT)
542                 dwc2_handle_wakeup_detected_intr(hsotg);
543         if (gintsts & GINTSTS_USBSUSP)
544                 dwc2_handle_usb_suspend_intr(hsotg);
545
546         if (gintsts & GINTSTS_PRTINT) {
547                 /*
548                  * The port interrupt occurs while in device mode with HPRT0
549                  * Port Enable/Disable
550                  */
551                 if (dwc2_is_device_mode(hsotg)) {
552                         dev_dbg(hsotg->dev,
553                                 " --Port interrupt received in Device mode--\n");
554                         dwc2_handle_usb_port_intr(hsotg);
555                         retval = IRQ_HANDLED;
556                 }
557         }
558
559 out:
560         spin_unlock(&hsotg->lock);
561         return retval;
562 }