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1 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
2 /*
3  * core_intr.c - DesignWare HS OTG Controller common interrupt handling
4  *
5  * Copyright (C) 2004-2013 Synopsys, Inc.
6  */
7 
8 /*
9  * This file contains the common interrupt handlers
10  */
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/moduleparam.h>
14 #include <linux/spinlock.h>
15 #include <linux/interrupt.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/io.h>
18 #include <linux/slab.h>
19 #include <linux/usb.h>
20 
21 #include <linux/usb/hcd.h>
22 #include <linux/usb/ch11.h>
23 
24 #include "core.h"
25 #include "hcd.h"
26 
dwc2_op_state_str(struct dwc2_hsotg * hsotg)27 static const char *dwc2_op_state_str(struct dwc2_hsotg *hsotg)
28 {
29 	switch (hsotg->op_state) {
30 	case OTG_STATE_A_HOST:
31 		return "a_host";
32 	case OTG_STATE_A_SUSPEND:
33 		return "a_suspend";
34 	case OTG_STATE_A_PERIPHERAL:
35 		return "a_peripheral";
36 	case OTG_STATE_B_PERIPHERAL:
37 		return "b_peripheral";
38 	case OTG_STATE_B_HOST:
39 		return "b_host";
40 	default:
41 		return "unknown";
42 	}
43 }
44 
45 /**
46  * dwc2_handle_usb_port_intr - handles OTG PRTINT interrupts.
47  * When the PRTINT interrupt fires, there are certain status bits in the Host
48  * Port that needs to get cleared.
49  *
50  * @hsotg: Programming view of DWC_otg controller
51  */
dwc2_handle_usb_port_intr(struct dwc2_hsotg * hsotg)52 static void dwc2_handle_usb_port_intr(struct dwc2_hsotg *hsotg)
53 {
54 	u32 hprt0 = dwc2_readl(hsotg, HPRT0);
55 
56 	if (hprt0 & HPRT0_ENACHG) {
57 		hprt0 &= ~HPRT0_ENA;
58 		dwc2_writel(hsotg, hprt0, HPRT0);
59 	}
60 }
61 
62 /**
63  * dwc2_handle_mode_mismatch_intr() - Logs a mode mismatch warning message
64  *
65  * @hsotg: Programming view of DWC_otg controller
66  */
dwc2_handle_mode_mismatch_intr(struct dwc2_hsotg * hsotg)67 static void dwc2_handle_mode_mismatch_intr(struct dwc2_hsotg *hsotg)
68 {
69 	/* Clear interrupt */
70 	dwc2_writel(hsotg, GINTSTS_MODEMIS, GINTSTS);
71 
72 	dev_warn(hsotg->dev, "Mode Mismatch Interrupt: currently in %s mode\n",
73 		 dwc2_is_host_mode(hsotg) ? "Host" : "Device");
74 }
75 
76 /**
77  * dwc2_handle_otg_intr() - Handles the OTG Interrupts. It reads the OTG
78  * Interrupt Register (GOTGINT) to determine what interrupt has occurred.
79  *
80  * @hsotg: Programming view of DWC_otg controller
81  */
dwc2_handle_otg_intr(struct dwc2_hsotg * hsotg)82 static void dwc2_handle_otg_intr(struct dwc2_hsotg *hsotg)
83 {
84 	u32 gotgint;
85 	u32 gotgctl;
86 	u32 gintmsk;
87 
88 	gotgint = dwc2_readl(hsotg, GOTGINT);
89 	gotgctl = dwc2_readl(hsotg, GOTGCTL);
90 	dev_dbg(hsotg->dev, "++OTG Interrupt gotgint=%0x [%s]\n", gotgint,
91 		dwc2_op_state_str(hsotg));
92 
93 	if (gotgint & GOTGINT_SES_END_DET) {
94 		dev_dbg(hsotg->dev,
95 			" ++OTG Interrupt: Session End Detected++ (%s)\n",
96 			dwc2_op_state_str(hsotg));
97 		gotgctl = dwc2_readl(hsotg, GOTGCTL);
98 
99 		if (dwc2_is_device_mode(hsotg))
100 			dwc2_hsotg_disconnect(hsotg);
101 
102 		if (hsotg->op_state == OTG_STATE_B_HOST) {
103 			hsotg->op_state = OTG_STATE_B_PERIPHERAL;
104 		} else {
105 			/*
106 			 * If not B_HOST and Device HNP still set, HNP did
107 			 * not succeed!
108 			 */
109 			if (gotgctl & GOTGCTL_DEVHNPEN) {
110 				dev_dbg(hsotg->dev, "Session End Detected\n");
111 				dev_err(hsotg->dev,
112 					"Device Not Connected/Responding!\n");
113 			}
114 
115 			/*
116 			 * If Session End Detected the B-Cable has been
117 			 * disconnected
118 			 */
119 			/* Reset to a clean state */
120 			hsotg->lx_state = DWC2_L0;
121 		}
122 
123 		gotgctl = dwc2_readl(hsotg, GOTGCTL);
124 		gotgctl &= ~GOTGCTL_DEVHNPEN;
125 		dwc2_writel(hsotg, gotgctl, GOTGCTL);
126 	}
127 
128 	if (gotgint & GOTGINT_SES_REQ_SUC_STS_CHNG) {
129 		dev_dbg(hsotg->dev,
130 			" ++OTG Interrupt: Session Request Success Status Change++\n");
131 		gotgctl = dwc2_readl(hsotg, GOTGCTL);
132 		if (gotgctl & GOTGCTL_SESREQSCS) {
133 			if (hsotg->params.phy_type == DWC2_PHY_TYPE_PARAM_FS &&
134 			    hsotg->params.i2c_enable) {
135 				hsotg->srp_success = 1;
136 			} else {
137 				/* Clear Session Request */
138 				gotgctl = dwc2_readl(hsotg, GOTGCTL);
139 				gotgctl &= ~GOTGCTL_SESREQ;
140 				dwc2_writel(hsotg, gotgctl, GOTGCTL);
141 			}
142 		}
143 	}
144 
145 	if (gotgint & GOTGINT_HST_NEG_SUC_STS_CHNG) {
146 		/*
147 		 * Print statements during the HNP interrupt handling
148 		 * can cause it to fail
149 		 */
150 		gotgctl = dwc2_readl(hsotg, GOTGCTL);
151 		/*
152 		 * WA for 3.00a- HW is not setting cur_mode, even sometimes
153 		 * this does not help
154 		 */
155 		if (hsotg->hw_params.snpsid >= DWC2_CORE_REV_3_00a)
156 			udelay(100);
157 		if (gotgctl & GOTGCTL_HSTNEGSCS) {
158 			if (dwc2_is_host_mode(hsotg)) {
159 				hsotg->op_state = OTG_STATE_B_HOST;
160 				/*
161 				 * Need to disable SOF interrupt immediately.
162 				 * When switching from device to host, the PCD
163 				 * interrupt handler won't handle the interrupt
164 				 * if host mode is already set. The HCD
165 				 * interrupt handler won't get called if the
166 				 * HCD state is HALT. This means that the
167 				 * interrupt does not get handled and Linux
168 				 * complains loudly.
169 				 */
170 				gintmsk = dwc2_readl(hsotg, GINTMSK);
171 				gintmsk &= ~GINTSTS_SOF;
172 				dwc2_writel(hsotg, gintmsk, GINTMSK);
173 
174 				/*
175 				 * Call callback function with spin lock
176 				 * released
177 				 */
178 				spin_unlock(&hsotg->lock);
179 
180 				/* Initialize the Core for Host mode */
181 				dwc2_hcd_start(hsotg);
182 				spin_lock(&hsotg->lock);
183 				hsotg->op_state = OTG_STATE_B_HOST;
184 			}
185 		} else {
186 			gotgctl = dwc2_readl(hsotg, GOTGCTL);
187 			gotgctl &= ~(GOTGCTL_HNPREQ | GOTGCTL_DEVHNPEN);
188 			dwc2_writel(hsotg, gotgctl, GOTGCTL);
189 			dev_dbg(hsotg->dev, "HNP Failed\n");
190 			dev_err(hsotg->dev,
191 				"Device Not Connected/Responding\n");
192 		}
193 	}
194 
195 	if (gotgint & GOTGINT_HST_NEG_DET) {
196 		/*
197 		 * The disconnect interrupt is set at the same time as
198 		 * Host Negotiation Detected. During the mode switch all
199 		 * interrupts are cleared so the disconnect interrupt
200 		 * handler will not get executed.
201 		 */
202 		dev_dbg(hsotg->dev,
203 			" ++OTG Interrupt: Host Negotiation Detected++ (%s)\n",
204 			(dwc2_is_host_mode(hsotg) ? "Host" : "Device"));
205 		if (dwc2_is_device_mode(hsotg)) {
206 			dev_dbg(hsotg->dev, "a_suspend->a_peripheral (%d)\n",
207 				hsotg->op_state);
208 			spin_unlock(&hsotg->lock);
209 			dwc2_hcd_disconnect(hsotg, false);
210 			spin_lock(&hsotg->lock);
211 			hsotg->op_state = OTG_STATE_A_PERIPHERAL;
212 		} else {
213 			/* Need to disable SOF interrupt immediately */
214 			gintmsk = dwc2_readl(hsotg, GINTMSK);
215 			gintmsk &= ~GINTSTS_SOF;
216 			dwc2_writel(hsotg, gintmsk, GINTMSK);
217 			spin_unlock(&hsotg->lock);
218 			dwc2_hcd_start(hsotg);
219 			spin_lock(&hsotg->lock);
220 			hsotg->op_state = OTG_STATE_A_HOST;
221 		}
222 	}
223 
224 	if (gotgint & GOTGINT_A_DEV_TOUT_CHG)
225 		dev_dbg(hsotg->dev,
226 			" ++OTG Interrupt: A-Device Timeout Change++\n");
227 	if (gotgint & GOTGINT_DBNCE_DONE)
228 		dev_dbg(hsotg->dev, " ++OTG Interrupt: Debounce Done++\n");
229 
230 	/* Clear GOTGINT */
231 	dwc2_writel(hsotg, gotgint, GOTGINT);
232 }
233 
234 /**
235  * dwc2_handle_conn_id_status_change_intr() - Handles the Connector ID Status
236  * Change Interrupt
237  *
238  * @hsotg: Programming view of DWC_otg controller
239  *
240  * Reads the OTG Interrupt Register (GOTCTL) to determine whether this is a
241  * Device to Host Mode transition or a Host to Device Mode transition. This only
242  * occurs when the cable is connected/removed from the PHY connector.
243  */
dwc2_handle_conn_id_status_change_intr(struct dwc2_hsotg * hsotg)244 static void dwc2_handle_conn_id_status_change_intr(struct dwc2_hsotg *hsotg)
245 {
246 	u32 gintmsk;
247 
248 	/* Clear interrupt */
249 	dwc2_writel(hsotg, GINTSTS_CONIDSTSCHNG, GINTSTS);
250 
251 	/* Need to disable SOF interrupt immediately */
252 	gintmsk = dwc2_readl(hsotg, GINTMSK);
253 	gintmsk &= ~GINTSTS_SOF;
254 	dwc2_writel(hsotg, gintmsk, GINTMSK);
255 
256 	dev_dbg(hsotg->dev, " ++Connector ID Status Change Interrupt++  (%s)\n",
257 		dwc2_is_host_mode(hsotg) ? "Host" : "Device");
258 
259 	/*
260 	 * Need to schedule a work, as there are possible DELAY function calls.
261 	 */
262 	if (hsotg->wq_otg)
263 		queue_work(hsotg->wq_otg, &hsotg->wf_otg);
264 }
265 
266 /**
267  * dwc2_handle_session_req_intr() - This interrupt indicates that a device is
268  * initiating the Session Request Protocol to request the host to turn on bus
269  * power so a new session can begin
270  *
271  * @hsotg: Programming view of DWC_otg controller
272  *
273  * This handler responds by turning on bus power. If the DWC_otg controller is
274  * in low power mode, this handler brings the controller out of low power mode
275  * before turning on bus power.
276  */
dwc2_handle_session_req_intr(struct dwc2_hsotg * hsotg)277 static void dwc2_handle_session_req_intr(struct dwc2_hsotg *hsotg)
278 {
279 	int ret;
280 	u32 hprt0;
281 
282 	/* Clear interrupt */
283 	dwc2_writel(hsotg, GINTSTS_SESSREQINT, GINTSTS);
284 
285 	dev_dbg(hsotg->dev, "Session request interrupt - lx_state=%d\n",
286 		hsotg->lx_state);
287 
288 	if (dwc2_is_device_mode(hsotg)) {
289 		if (hsotg->lx_state == DWC2_L2) {
290 			if (hsotg->in_ppd) {
291 				ret = dwc2_exit_partial_power_down(hsotg, 0,
292 								   true);
293 				if (ret)
294 					dev_err(hsotg->dev,
295 						"exit power_down failed\n");
296 			}
297 
298 			/* Exit gadget mode clock gating. */
299 			if (hsotg->params.power_down ==
300 			    DWC2_POWER_DOWN_PARAM_NONE && hsotg->bus_suspended &&
301 			    !hsotg->params.no_clock_gating)
302 				dwc2_gadget_exit_clock_gating(hsotg, 0);
303 		}
304 
305 		/*
306 		 * Report disconnect if there is any previous session
307 		 * established
308 		 */
309 		dwc2_hsotg_disconnect(hsotg);
310 	} else {
311 		/* Turn on the port power bit. */
312 		hprt0 = dwc2_read_hprt0(hsotg);
313 		hprt0 |= HPRT0_PWR;
314 		dwc2_writel(hsotg, hprt0, HPRT0);
315 		/* Connect hcd after port power is set. */
316 		dwc2_hcd_connect(hsotg);
317 	}
318 }
319 
320 /**
321  * dwc2_wakeup_from_lpm_l1 - Exit the device from LPM L1 state
322  *
323  * @hsotg: Programming view of DWC_otg controller
324  *
325  */
dwc2_wakeup_from_lpm_l1(struct dwc2_hsotg * hsotg,bool remotewakeup)326 void dwc2_wakeup_from_lpm_l1(struct dwc2_hsotg *hsotg, bool remotewakeup)
327 {
328 	u32 glpmcfg;
329 	u32 pcgctl;
330 	u32 dctl;
331 
332 	if (hsotg->lx_state != DWC2_L1) {
333 		dev_err(hsotg->dev, "Core isn't in DWC2_L1 state\n");
334 		return;
335 	}
336 
337 	glpmcfg = dwc2_readl(hsotg, GLPMCFG);
338 	if (dwc2_is_device_mode(hsotg)) {
339 		dev_dbg(hsotg->dev, "Exit from L1 state, remotewakeup=%d\n", remotewakeup);
340 		glpmcfg &= ~GLPMCFG_ENBLSLPM;
341 		glpmcfg &= ~GLPMCFG_HIRD_THRES_MASK;
342 		dwc2_writel(hsotg, glpmcfg, GLPMCFG);
343 
344 		pcgctl = dwc2_readl(hsotg, PCGCTL);
345 		pcgctl &= ~PCGCTL_ENBL_SLEEP_GATING;
346 		dwc2_writel(hsotg, pcgctl, PCGCTL);
347 
348 		glpmcfg = dwc2_readl(hsotg, GLPMCFG);
349 		if (glpmcfg & GLPMCFG_ENBESL) {
350 			glpmcfg |= GLPMCFG_RSTRSLPSTS;
351 			dwc2_writel(hsotg, glpmcfg, GLPMCFG);
352 		}
353 
354 		if (remotewakeup) {
355 			if (dwc2_hsotg_wait_bit_set(hsotg, GLPMCFG, GLPMCFG_L1RESUMEOK, 1000)) {
356 				dev_warn(hsotg->dev, "%s: timeout GLPMCFG_L1RESUMEOK\n", __func__);
357 				goto fail;
358 				return;
359 			}
360 
361 			dctl = dwc2_readl(hsotg, DCTL);
362 			dctl |= DCTL_RMTWKUPSIG;
363 			dwc2_writel(hsotg, dctl, DCTL);
364 
365 			if (dwc2_hsotg_wait_bit_set(hsotg, GINTSTS, GINTSTS_WKUPINT, 1000)) {
366 				dev_warn(hsotg->dev, "%s: timeout GINTSTS_WKUPINT\n", __func__);
367 				goto fail;
368 				return;
369 			}
370 		}
371 
372 		glpmcfg = dwc2_readl(hsotg, GLPMCFG);
373 		if (glpmcfg & GLPMCFG_COREL1RES_MASK || glpmcfg & GLPMCFG_SLPSTS ||
374 		    glpmcfg & GLPMCFG_L1RESUMEOK) {
375 			goto fail;
376 			return;
377 		}
378 
379 		/* Inform gadget to exit from L1 */
380 		call_gadget(hsotg, resume);
381 		/* Change to L0 state */
382 		hsotg->lx_state = DWC2_L0;
383 		hsotg->bus_suspended = false;
384 fail:		dwc2_gadget_init_lpm(hsotg);
385 	} else {
386 		/* TODO */
387 		dev_err(hsotg->dev, "Host side LPM is not supported.\n");
388 		return;
389 	}
390 }
391 
392 /*
393  * This interrupt indicates that the DWC_otg controller has detected a
394  * resume or remote wakeup sequence. If the DWC_otg controller is in
395  * low power mode, the handler must brings the controller out of low
396  * power mode. The controller automatically begins resume signaling.
397  * The handler schedules a time to stop resume signaling.
398  */
dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg * hsotg)399 static void dwc2_handle_wakeup_detected_intr(struct dwc2_hsotg *hsotg)
400 {
401 	int ret;
402 
403 	/* Clear interrupt */
404 	dwc2_writel(hsotg, GINTSTS_WKUPINT, GINTSTS);
405 
406 	dev_dbg(hsotg->dev, "++Resume or Remote Wakeup Detected Interrupt++\n");
407 	dev_dbg(hsotg->dev, "%s lxstate = %d\n", __func__, hsotg->lx_state);
408 
409 	if (hsotg->lx_state == DWC2_L1) {
410 		dwc2_wakeup_from_lpm_l1(hsotg, false);
411 		return;
412 	}
413 
414 	if (dwc2_is_device_mode(hsotg)) {
415 		dev_dbg(hsotg->dev, "DSTS=0x%0x\n",
416 			dwc2_readl(hsotg, DSTS));
417 		if (hsotg->lx_state == DWC2_L2) {
418 			if (hsotg->in_ppd) {
419 				u32 dctl = dwc2_readl(hsotg, DCTL);
420 				/* Clear Remote Wakeup Signaling */
421 				dctl &= ~DCTL_RMTWKUPSIG;
422 				dwc2_writel(hsotg, dctl, DCTL);
423 				ret = dwc2_exit_partial_power_down(hsotg, 1,
424 								   true);
425 				if (ret)
426 					dev_err(hsotg->dev,
427 						"exit partial_power_down failed\n");
428 				call_gadget(hsotg, resume);
429 			}
430 
431 			/* Exit gadget mode clock gating. */
432 			if (hsotg->params.power_down ==
433 			    DWC2_POWER_DOWN_PARAM_NONE && hsotg->bus_suspended &&
434 			    !hsotg->params.no_clock_gating)
435 				dwc2_gadget_exit_clock_gating(hsotg, 0);
436 		} else {
437 			/* Change to L0 state */
438 			hsotg->lx_state = DWC2_L0;
439 		}
440 	} else {
441 		if (hsotg->lx_state == DWC2_L2) {
442 			if (hsotg->in_ppd) {
443 				ret = dwc2_exit_partial_power_down(hsotg, 1,
444 								   true);
445 				if (ret)
446 					dev_err(hsotg->dev,
447 						"exit partial_power_down failed\n");
448 			}
449 
450 			if (hsotg->params.power_down ==
451 			    DWC2_POWER_DOWN_PARAM_NONE && hsotg->bus_suspended &&
452 			    !hsotg->params.no_clock_gating)
453 				dwc2_host_exit_clock_gating(hsotg, 1);
454 
455 			/*
456 			 * If we've got this quirk then the PHY is stuck upon
457 			 * wakeup.  Assert reset.  This will propagate out and
458 			 * eventually we'll re-enumerate the device.  Not great
459 			 * but the best we can do.  We can't call phy_reset()
460 			 * at interrupt time but there's no hurry, so we'll
461 			 * schedule it for later.
462 			 */
463 			if (hsotg->reset_phy_on_wake)
464 				dwc2_host_schedule_phy_reset(hsotg);
465 
466 			mod_timer(&hsotg->wkp_timer,
467 				  jiffies + msecs_to_jiffies(71));
468 		} else {
469 			/* Change to L0 state */
470 			hsotg->lx_state = DWC2_L0;
471 		}
472 	}
473 }
474 
475 /*
476  * This interrupt indicates that a device has been disconnected from the
477  * root port
478  */
dwc2_handle_disconnect_intr(struct dwc2_hsotg * hsotg)479 static void dwc2_handle_disconnect_intr(struct dwc2_hsotg *hsotg)
480 {
481 	dwc2_writel(hsotg, GINTSTS_DISCONNINT, GINTSTS);
482 
483 	dev_dbg(hsotg->dev, "++Disconnect Detected Interrupt++ (%s) %s\n",
484 		dwc2_is_host_mode(hsotg) ? "Host" : "Device",
485 		dwc2_op_state_str(hsotg));
486 
487 	if (hsotg->op_state == OTG_STATE_A_HOST)
488 		dwc2_hcd_disconnect(hsotg, false);
489 }
490 
491 /*
492  * This interrupt indicates that SUSPEND state has been detected on the USB.
493  *
494  * For HNP the USB Suspend interrupt signals the change from "a_peripheral"
495  * to "a_host".
496  *
497  * When power management is enabled the core will be put in low power mode.
498  */
dwc2_handle_usb_suspend_intr(struct dwc2_hsotg * hsotg)499 static void dwc2_handle_usb_suspend_intr(struct dwc2_hsotg *hsotg)
500 {
501 	u32 dsts;
502 	int ret;
503 
504 	/* Clear interrupt */
505 	dwc2_writel(hsotg, GINTSTS_USBSUSP, GINTSTS);
506 
507 	dev_dbg(hsotg->dev, "USB SUSPEND\n");
508 
509 	if (dwc2_is_device_mode(hsotg)) {
510 		/*
511 		 * Check the Device status register to determine if the Suspend
512 		 * state is active
513 		 */
514 		dsts = dwc2_readl(hsotg, DSTS);
515 		dev_dbg(hsotg->dev, "%s: DSTS=0x%0x\n", __func__, dsts);
516 		dev_dbg(hsotg->dev,
517 			"DSTS.Suspend Status=%d HWCFG4.Power Optimize=%d HWCFG4.Hibernation=%d\n",
518 			!!(dsts & DSTS_SUSPSTS),
519 			hsotg->hw_params.power_optimized,
520 			hsotg->hw_params.hibernation);
521 
522 		/* Ignore suspend request before enumeration */
523 		if (!dwc2_is_device_connected(hsotg)) {
524 			dev_dbg(hsotg->dev,
525 				"ignore suspend request before enumeration\n");
526 			return;
527 		}
528 		if (dsts & DSTS_SUSPSTS) {
529 			switch (hsotg->params.power_down) {
530 			case DWC2_POWER_DOWN_PARAM_PARTIAL:
531 				ret = dwc2_enter_partial_power_down(hsotg);
532 				if (ret)
533 					dev_err(hsotg->dev,
534 						"enter partial_power_down failed\n");
535 
536 				udelay(100);
537 
538 				/* Ask phy to be suspended */
539 				if (!IS_ERR_OR_NULL(hsotg->uphy))
540 					usb_phy_set_suspend(hsotg->uphy, true);
541 				break;
542 			case DWC2_POWER_DOWN_PARAM_HIBERNATION:
543 				ret = dwc2_enter_hibernation(hsotg, 0);
544 				if (ret)
545 					dev_err(hsotg->dev,
546 						"enter hibernation failed\n");
547 				break;
548 			case DWC2_POWER_DOWN_PARAM_NONE:
549 				/*
550 				 * If neither hibernation nor partial power down are supported,
551 				 * clock gating is used to save power.
552 				 */
553 				if (!hsotg->params.no_clock_gating)
554 					dwc2_gadget_enter_clock_gating(hsotg);
555 			}
556 
557 			/*
558 			 * Change to L2 (suspend) state before releasing
559 			 * spinlock
560 			 */
561 			hsotg->lx_state = DWC2_L2;
562 
563 			/* Call gadget suspend callback */
564 			call_gadget(hsotg, suspend);
565 		}
566 	} else {
567 		if (hsotg->op_state == OTG_STATE_A_PERIPHERAL) {
568 			dev_dbg(hsotg->dev, "a_peripheral->a_host\n");
569 
570 			/* Change to L2 (suspend) state */
571 			hsotg->lx_state = DWC2_L2;
572 			/* Clear the a_peripheral flag, back to a_host */
573 			spin_unlock(&hsotg->lock);
574 			dwc2_hcd_start(hsotg);
575 			spin_lock(&hsotg->lock);
576 			hsotg->op_state = OTG_STATE_A_HOST;
577 		}
578 	}
579 }
580 
581 /**
582  * dwc2_handle_lpm_intr - GINTSTS_LPMTRANRCVD Interrupt handler
583  *
584  * @hsotg: Programming view of DWC_otg controller
585  *
586  */
dwc2_handle_lpm_intr(struct dwc2_hsotg * hsotg)587 static void dwc2_handle_lpm_intr(struct dwc2_hsotg *hsotg)
588 {
589 	u32 glpmcfg;
590 	u32 pcgcctl;
591 	u32 hird;
592 	u32 hird_thres;
593 	u32 hird_thres_en;
594 	u32 enslpm;
595 
596 	/* Clear interrupt */
597 	dwc2_writel(hsotg, GINTSTS_LPMTRANRCVD, GINTSTS);
598 
599 	glpmcfg = dwc2_readl(hsotg, GLPMCFG);
600 
601 	if (!(glpmcfg & GLPMCFG_LPMCAP)) {
602 		dev_err(hsotg->dev, "Unexpected LPM interrupt\n");
603 		return;
604 	}
605 
606 	hird = (glpmcfg & GLPMCFG_HIRD_MASK) >> GLPMCFG_HIRD_SHIFT;
607 	hird_thres = (glpmcfg & GLPMCFG_HIRD_THRES_MASK &
608 			~GLPMCFG_HIRD_THRES_EN) >> GLPMCFG_HIRD_THRES_SHIFT;
609 	hird_thres_en = glpmcfg & GLPMCFG_HIRD_THRES_EN;
610 	enslpm = glpmcfg & GLPMCFG_ENBLSLPM;
611 
612 	if (dwc2_is_device_mode(hsotg)) {
613 		dev_dbg(hsotg->dev, "HIRD_THRES_EN = %d\n", hird_thres_en);
614 
615 		if (hird_thres_en && hird >= hird_thres) {
616 			dev_dbg(hsotg->dev, "L1 with utmi_l1_suspend_n\n");
617 		} else if (enslpm) {
618 			dev_dbg(hsotg->dev, "L1 with utmi_sleep_n\n");
619 		} else {
620 			dev_dbg(hsotg->dev, "Entering Sleep with L1 Gating\n");
621 
622 			pcgcctl = dwc2_readl(hsotg, PCGCTL);
623 			pcgcctl |= PCGCTL_ENBL_SLEEP_GATING;
624 			dwc2_writel(hsotg, pcgcctl, PCGCTL);
625 		}
626 		/**
627 		 * Examine prt_sleep_sts after TL1TokenTetry period max (10 us)
628 		 */
629 		udelay(10);
630 
631 		glpmcfg = dwc2_readl(hsotg, GLPMCFG);
632 
633 		if (glpmcfg & GLPMCFG_SLPSTS) {
634 			/* Save the current state */
635 			hsotg->lx_state = DWC2_L1;
636 			dev_dbg(hsotg->dev,
637 				"Core is in L1 sleep glpmcfg=%08x\n", glpmcfg);
638 
639 			/* Inform gadget that we are in L1 state */
640 			call_gadget(hsotg, suspend);
641 		}
642 	}
643 }
644 
645 #define GINTMSK_COMMON	(GINTSTS_WKUPINT | GINTSTS_SESSREQINT |		\
646 			 GINTSTS_CONIDSTSCHNG | GINTSTS_OTGINT |	\
647 			 GINTSTS_MODEMIS | GINTSTS_DISCONNINT |		\
648 			 GINTSTS_USBSUSP | GINTSTS_PRTINT |		\
649 			 GINTSTS_LPMTRANRCVD)
650 
651 /*
652  * This function returns the Core Interrupt register
653  */
dwc2_read_common_intr(struct dwc2_hsotg * hsotg)654 static u32 dwc2_read_common_intr(struct dwc2_hsotg *hsotg)
655 {
656 	u32 gintsts;
657 	u32 gintmsk;
658 	u32 gahbcfg;
659 	u32 gintmsk_common = GINTMSK_COMMON;
660 
661 	gintsts = dwc2_readl(hsotg, GINTSTS);
662 	gintmsk = dwc2_readl(hsotg, GINTMSK);
663 	gahbcfg = dwc2_readl(hsotg, GAHBCFG);
664 
665 	/* If any common interrupts set */
666 	if (gintsts & gintmsk_common)
667 		dev_dbg(hsotg->dev, "gintsts=%08x  gintmsk=%08x\n",
668 			gintsts, gintmsk);
669 
670 	if (gahbcfg & GAHBCFG_GLBL_INTR_EN)
671 		return gintsts & gintmsk & gintmsk_common;
672 	else
673 		return 0;
674 }
675 
676 /**
677  * dwc_handle_gpwrdn_disc_det() - Handles the gpwrdn disconnect detect.
678  * Exits hibernation without restoring registers.
679  *
680  * @hsotg: Programming view of DWC_otg controller
681  * @gpwrdn: GPWRDN register
682  */
dwc_handle_gpwrdn_disc_det(struct dwc2_hsotg * hsotg,u32 gpwrdn)683 static inline void dwc_handle_gpwrdn_disc_det(struct dwc2_hsotg *hsotg,
684 					      u32 gpwrdn)
685 {
686 	u32 gpwrdn_tmp;
687 
688 	/* Switch-on voltage to the core */
689 	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
690 	gpwrdn_tmp &= ~GPWRDN_PWRDNSWTCH;
691 	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
692 	udelay(5);
693 
694 	/* Reset core */
695 	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
696 	gpwrdn_tmp &= ~GPWRDN_PWRDNRSTN;
697 	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
698 	udelay(5);
699 
700 	/* Disable Power Down Clamp */
701 	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
702 	gpwrdn_tmp &= ~GPWRDN_PWRDNCLMP;
703 	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
704 	udelay(5);
705 
706 	/* Deassert reset core */
707 	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
708 	gpwrdn_tmp |= GPWRDN_PWRDNRSTN;
709 	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
710 	udelay(5);
711 
712 	/* Disable PMU interrupt */
713 	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
714 	gpwrdn_tmp &= ~GPWRDN_PMUINTSEL;
715 	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
716 
717 	/* De-assert Wakeup Logic */
718 	gpwrdn_tmp = dwc2_readl(hsotg, GPWRDN);
719 	gpwrdn_tmp &= ~GPWRDN_PMUACTV;
720 	dwc2_writel(hsotg, gpwrdn_tmp, GPWRDN);
721 
722 	hsotg->hibernated = 0;
723 	hsotg->bus_suspended = 0;
724 
725 	if (gpwrdn & GPWRDN_IDSTS) {
726 		hsotg->op_state = OTG_STATE_B_PERIPHERAL;
727 		dwc2_core_init(hsotg, false);
728 		dwc2_enable_global_interrupts(hsotg);
729 		dwc2_hsotg_core_init_disconnected(hsotg, false);
730 		dwc2_hsotg_core_connect(hsotg);
731 	} else {
732 		hsotg->op_state = OTG_STATE_A_HOST;
733 
734 		/* Initialize the Core for Host mode */
735 		dwc2_core_init(hsotg, false);
736 		dwc2_enable_global_interrupts(hsotg);
737 		dwc2_hcd_start(hsotg);
738 	}
739 }
740 
741 /*
742  * GPWRDN interrupt handler.
743  *
744  * The GPWRDN interrupts are those that occur in both Host and
745  * Device mode while core is in hibernated state.
746  */
dwc2_handle_gpwrdn_intr(struct dwc2_hsotg * hsotg)747 static int dwc2_handle_gpwrdn_intr(struct dwc2_hsotg *hsotg)
748 {
749 	u32 gpwrdn;
750 	int linestate;
751 	int ret = 0;
752 
753 	gpwrdn = dwc2_readl(hsotg, GPWRDN);
754 	/* clear all interrupt */
755 	dwc2_writel(hsotg, gpwrdn, GPWRDN);
756 	linestate = (gpwrdn & GPWRDN_LINESTATE_MASK) >> GPWRDN_LINESTATE_SHIFT;
757 	dev_dbg(hsotg->dev,
758 		"%s: dwc2_handle_gpwrdwn_intr called gpwrdn= %08x\n", __func__,
759 		gpwrdn);
760 
761 	if ((gpwrdn & GPWRDN_DISCONN_DET) &&
762 	    (gpwrdn & GPWRDN_DISCONN_DET_MSK) && !linestate) {
763 		dev_dbg(hsotg->dev, "%s: GPWRDN_DISCONN_DET\n", __func__);
764 		/*
765 		 * Call disconnect detect function to exit from
766 		 * hibernation
767 		 */
768 		dwc_handle_gpwrdn_disc_det(hsotg, gpwrdn);
769 	} else if ((gpwrdn & GPWRDN_LNSTSCHG) &&
770 		   (gpwrdn & GPWRDN_LNSTSCHG_MSK) && linestate) {
771 		dev_dbg(hsotg->dev, "%s: GPWRDN_LNSTSCHG\n", __func__);
772 		if (hsotg->hw_params.hibernation &&
773 		    hsotg->hibernated) {
774 			if (gpwrdn & GPWRDN_IDSTS) {
775 				ret = dwc2_exit_hibernation(hsotg, 0, 0, 0);
776 				if (ret)
777 					dev_err(hsotg->dev,
778 						"exit hibernation failed.\n");
779 				call_gadget(hsotg, resume);
780 			} else {
781 				ret = dwc2_exit_hibernation(hsotg, 1, 0, 1);
782 				if (ret)
783 					dev_err(hsotg->dev,
784 						"exit hibernation failed.\n");
785 			}
786 		}
787 	} else if ((gpwrdn & GPWRDN_RST_DET) &&
788 		   (gpwrdn & GPWRDN_RST_DET_MSK)) {
789 		dev_dbg(hsotg->dev, "%s: GPWRDN_RST_DET\n", __func__);
790 		if (!linestate) {
791 			ret = dwc2_exit_hibernation(hsotg, 0, 1, 0);
792 			if (ret)
793 				dev_err(hsotg->dev,
794 					"exit hibernation failed.\n");
795 		}
796 	} else if ((gpwrdn & GPWRDN_STS_CHGINT) &&
797 		   (gpwrdn & GPWRDN_STS_CHGINT_MSK)) {
798 		dev_dbg(hsotg->dev, "%s: GPWRDN_STS_CHGINT\n", __func__);
799 		/*
800 		 * As GPWRDN_STS_CHGINT exit from hibernation flow is
801 		 * the same as in GPWRDN_DISCONN_DET flow. Call
802 		 * disconnect detect helper function to exit from
803 		 * hibernation.
804 		 */
805 		dwc_handle_gpwrdn_disc_det(hsotg, gpwrdn);
806 	}
807 
808 	return ret;
809 }
810 
811 /*
812  * Common interrupt handler
813  *
814  * The common interrupts are those that occur in both Host and Device mode.
815  * This handler handles the following interrupts:
816  * - Mode Mismatch Interrupt
817  * - OTG Interrupt
818  * - Connector ID Status Change Interrupt
819  * - Disconnect Interrupt
820  * - Session Request Interrupt
821  * - Resume / Remote Wakeup Detected Interrupt
822  * - Suspend Interrupt
823  */
dwc2_handle_common_intr(int irq,void * dev)824 irqreturn_t dwc2_handle_common_intr(int irq, void *dev)
825 {
826 	struct dwc2_hsotg *hsotg = dev;
827 	u32 gintsts;
828 	irqreturn_t retval = IRQ_NONE;
829 
830 	spin_lock(&hsotg->lock);
831 
832 	if (!dwc2_is_controller_alive(hsotg)) {
833 		dev_warn(hsotg->dev, "Controller is dead\n");
834 		goto out;
835 	}
836 
837 	/* Reading current frame number value in device or host modes. */
838 	if (dwc2_is_device_mode(hsotg))
839 		hsotg->frame_number = (dwc2_readl(hsotg, DSTS)
840 				       & DSTS_SOFFN_MASK) >> DSTS_SOFFN_SHIFT;
841 	else
842 		hsotg->frame_number = (dwc2_readl(hsotg, HFNUM)
843 				       & HFNUM_FRNUM_MASK) >> HFNUM_FRNUM_SHIFT;
844 
845 	gintsts = dwc2_read_common_intr(hsotg);
846 	if (gintsts & ~GINTSTS_PRTINT)
847 		retval = IRQ_HANDLED;
848 
849 	/* In case of hibernated state gintsts must not work */
850 	if (hsotg->hibernated) {
851 		dwc2_handle_gpwrdn_intr(hsotg);
852 		retval = IRQ_HANDLED;
853 		goto out;
854 	}
855 
856 	if (gintsts & GINTSTS_MODEMIS)
857 		dwc2_handle_mode_mismatch_intr(hsotg);
858 	if (gintsts & GINTSTS_OTGINT)
859 		dwc2_handle_otg_intr(hsotg);
860 	if (gintsts & GINTSTS_CONIDSTSCHNG)
861 		dwc2_handle_conn_id_status_change_intr(hsotg);
862 	if (gintsts & GINTSTS_DISCONNINT)
863 		dwc2_handle_disconnect_intr(hsotg);
864 	if (gintsts & GINTSTS_SESSREQINT)
865 		dwc2_handle_session_req_intr(hsotg);
866 	if (gintsts & GINTSTS_WKUPINT)
867 		dwc2_handle_wakeup_detected_intr(hsotg);
868 	if (gintsts & GINTSTS_USBSUSP)
869 		dwc2_handle_usb_suspend_intr(hsotg);
870 	if (gintsts & GINTSTS_LPMTRANRCVD)
871 		dwc2_handle_lpm_intr(hsotg);
872 
873 	if (gintsts & GINTSTS_PRTINT) {
874 		/*
875 		 * The port interrupt occurs while in device mode with HPRT0
876 		 * Port Enable/Disable
877 		 */
878 		if (dwc2_is_device_mode(hsotg)) {
879 			dev_dbg(hsotg->dev,
880 				" --Port interrupt received in Device mode--\n");
881 			dwc2_handle_usb_port_intr(hsotg);
882 			retval = IRQ_HANDLED;
883 		}
884 	}
885 
886 out:
887 	spin_unlock(&hsotg->lock);
888 	return retval;
889 }
890