1/*
2 * hcd_intr.c - DesignWare HS OTG Controller host-mode 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 interrupt handlers for Host mode
39 */
40#include <linux/kernel.h>
41#include <linux/module.h>
42#include <linux/spinlock.h>
43#include <linux/interrupt.h>
44#include <linux/dma-mapping.h>
45#include <linux/io.h>
46#include <linux/slab.h>
47#include <linux/usb.h>
48
49#include <linux/usb/hcd.h>
50#include <linux/usb/ch11.h>
51
52#include "core.h"
53#include "hcd.h"
54
55/* This function is for debug only */
56static void dwc2_track_missed_sofs(struct dwc2_hsotg *hsotg)
57{
58#ifdef CONFIG_USB_DWC2_TRACK_MISSED_SOFS
59	u16 curr_frame_number = hsotg->frame_number;
60
61	if (hsotg->frame_num_idx < FRAME_NUM_ARRAY_SIZE) {
62		if (((hsotg->last_frame_num + 1) & HFNUM_MAX_FRNUM) !=
63		    curr_frame_number) {
64			hsotg->frame_num_array[hsotg->frame_num_idx] =
65					curr_frame_number;
66			hsotg->last_frame_num_array[hsotg->frame_num_idx] =
67					hsotg->last_frame_num;
68			hsotg->frame_num_idx++;
69		}
70	} else if (!hsotg->dumped_frame_num_array) {
71		int i;
72
73		dev_info(hsotg->dev, "Frame     Last Frame\n");
74		dev_info(hsotg->dev, "-----     ----------\n");
75		for (i = 0; i < FRAME_NUM_ARRAY_SIZE; i++) {
76			dev_info(hsotg->dev, "0x%04x    0x%04x\n",
77				 hsotg->frame_num_array[i],
78				 hsotg->last_frame_num_array[i]);
79		}
80		hsotg->dumped_frame_num_array = 1;
81	}
82	hsotg->last_frame_num = curr_frame_number;
83#endif
84}
85
86static void dwc2_hc_handle_tt_clear(struct dwc2_hsotg *hsotg,
87				    struct dwc2_host_chan *chan,
88				    struct dwc2_qtd *qtd)
89{
90	struct urb *usb_urb;
91
92	if (!chan->qh)
93		return;
94
95	if (chan->qh->dev_speed == USB_SPEED_HIGH)
96		return;
97
98	if (!qtd->urb)
99		return;
100
101	usb_urb = qtd->urb->priv;
102	if (!usb_urb || !usb_urb->dev || !usb_urb->dev->tt)
103		return;
104
105	if (qtd->urb->status != -EPIPE && qtd->urb->status != -EREMOTEIO) {
106		chan->qh->tt_buffer_dirty = 1;
107		if (usb_hub_clear_tt_buffer(usb_urb))
108			/* Clear failed; let's hope things work anyway */
109			chan->qh->tt_buffer_dirty = 0;
110	}
111}
112
113/*
114 * Handles the start-of-frame interrupt in host mode. Non-periodic
115 * transactions may be queued to the DWC_otg controller for the current
116 * (micro)frame. Periodic transactions may be queued to the controller
117 * for the next (micro)frame.
118 */
119static void dwc2_sof_intr(struct dwc2_hsotg *hsotg)
120{
121	struct list_head *qh_entry;
122	struct dwc2_qh *qh;
123	enum dwc2_transaction_type tr_type;
124
125#ifdef DEBUG_SOF
126	dev_vdbg(hsotg->dev, "--Start of Frame Interrupt--\n");
127#endif
128
129	hsotg->frame_number = dwc2_hcd_get_frame_number(hsotg);
130
131	dwc2_track_missed_sofs(hsotg);
132
133	/* Determine whether any periodic QHs should be executed */
134	qh_entry = hsotg->periodic_sched_inactive.next;
135	while (qh_entry != &hsotg->periodic_sched_inactive) {
136		qh = list_entry(qh_entry, struct dwc2_qh, qh_list_entry);
137		qh_entry = qh_entry->next;
138		if (dwc2_frame_num_le(qh->sched_frame, hsotg->frame_number))
139			/*
140			 * Move QH to the ready list to be executed next
141			 * (micro)frame
142			 */
143			list_move(&qh->qh_list_entry,
144				  &hsotg->periodic_sched_ready);
145	}
146	tr_type = dwc2_hcd_select_transactions(hsotg);
147	if (tr_type != DWC2_TRANSACTION_NONE)
148		dwc2_hcd_queue_transactions(hsotg, tr_type);
149
150	/* Clear interrupt */
151	writel(GINTSTS_SOF, hsotg->regs + GINTSTS);
152}
153
154/*
155 * Handles the Rx FIFO Level Interrupt, which indicates that there is
156 * at least one packet in the Rx FIFO. The packets are moved from the FIFO to
157 * memory if the DWC_otg controller is operating in Slave mode.
158 */
159static void dwc2_rx_fifo_level_intr(struct dwc2_hsotg *hsotg)
160{
161	u32 grxsts, chnum, bcnt, dpid, pktsts;
162	struct dwc2_host_chan *chan;
163
164	if (dbg_perio())
165		dev_vdbg(hsotg->dev, "--RxFIFO Level Interrupt--\n");
166
167	grxsts = readl(hsotg->regs + GRXSTSP);
168	chnum = (grxsts & GRXSTS_HCHNUM_MASK) >> GRXSTS_HCHNUM_SHIFT;
169	chan = hsotg->hc_ptr_array[chnum];
170	if (!chan) {
171		dev_err(hsotg->dev, "Unable to get corresponding channel\n");
172		return;
173	}
174
175	bcnt = (grxsts & GRXSTS_BYTECNT_MASK) >> GRXSTS_BYTECNT_SHIFT;
176	dpid = (grxsts & GRXSTS_DPID_MASK) >> GRXSTS_DPID_SHIFT;
177	pktsts = (grxsts & GRXSTS_PKTSTS_MASK) >> GRXSTS_PKTSTS_SHIFT;
178
179	/* Packet Status */
180	if (dbg_perio()) {
181		dev_vdbg(hsotg->dev, "    Ch num = %d\n", chnum);
182		dev_vdbg(hsotg->dev, "    Count = %d\n", bcnt);
183		dev_vdbg(hsotg->dev, "    DPID = %d, chan.dpid = %d\n", dpid,
184			 chan->data_pid_start);
185		dev_vdbg(hsotg->dev, "    PStatus = %d\n", pktsts);
186	}
187
188	switch (pktsts) {
189	case GRXSTS_PKTSTS_HCHIN:
190		/* Read the data into the host buffer */
191		if (bcnt > 0) {
192			dwc2_read_packet(hsotg, chan->xfer_buf, bcnt);
193
194			/* Update the HC fields for the next packet received */
195			chan->xfer_count += bcnt;
196			chan->xfer_buf += bcnt;
197		}
198		break;
199	case GRXSTS_PKTSTS_HCHIN_XFER_COMP:
200	case GRXSTS_PKTSTS_DATATOGGLEERR:
201	case GRXSTS_PKTSTS_HCHHALTED:
202		/* Handled in interrupt, just ignore data */
203		break;
204	default:
205		dev_err(hsotg->dev,
206			"RxFIFO Level Interrupt: Unknown status %d\n", pktsts);
207		break;
208	}
209}
210
211/*
212 * This interrupt occurs when the non-periodic Tx FIFO is half-empty. More
213 * data packets may be written to the FIFO for OUT transfers. More requests
214 * may be written to the non-periodic request queue for IN transfers. This
215 * interrupt is enabled only in Slave mode.
216 */
217static void dwc2_np_tx_fifo_empty_intr(struct dwc2_hsotg *hsotg)
218{
219	dev_vdbg(hsotg->dev, "--Non-Periodic TxFIFO Empty Interrupt--\n");
220	dwc2_hcd_queue_transactions(hsotg, DWC2_TRANSACTION_NON_PERIODIC);
221}
222
223/*
224 * This interrupt occurs when the periodic Tx FIFO is half-empty. More data
225 * packets may be written to the FIFO for OUT transfers. More requests may be
226 * written to the periodic request queue for IN transfers. This interrupt is
227 * enabled only in Slave mode.
228 */
229static void dwc2_perio_tx_fifo_empty_intr(struct dwc2_hsotg *hsotg)
230{
231	if (dbg_perio())
232		dev_vdbg(hsotg->dev, "--Periodic TxFIFO Empty Interrupt--\n");
233	dwc2_hcd_queue_transactions(hsotg, DWC2_TRANSACTION_PERIODIC);
234}
235
236static void dwc2_hprt0_enable(struct dwc2_hsotg *hsotg, u32 hprt0,
237			      u32 *hprt0_modify)
238{
239	struct dwc2_core_params *params = hsotg->core_params;
240	int do_reset = 0;
241	u32 usbcfg;
242	u32 prtspd;
243	u32 hcfg;
244	u32 fslspclksel;
245	u32 hfir;
246
247	dev_vdbg(hsotg->dev, "%s(%p)\n", __func__, hsotg);
248
249	/* Every time when port enables calculate HFIR.FrInterval */
250	hfir = readl(hsotg->regs + HFIR);
251	hfir &= ~HFIR_FRINT_MASK;
252	hfir |= dwc2_calc_frame_interval(hsotg) << HFIR_FRINT_SHIFT &
253		HFIR_FRINT_MASK;
254	writel(hfir, hsotg->regs + HFIR);
255
256	/* Check if we need to adjust the PHY clock speed for low power */
257	if (!params->host_support_fs_ls_low_power) {
258		/* Port has been enabled, set the reset change flag */
259		hsotg->flags.b.port_reset_change = 1;
260		return;
261	}
262
263	usbcfg = readl(hsotg->regs + GUSBCFG);
264	prtspd = (hprt0 & HPRT0_SPD_MASK) >> HPRT0_SPD_SHIFT;
265
266	if (prtspd == HPRT0_SPD_LOW_SPEED || prtspd == HPRT0_SPD_FULL_SPEED) {
267		/* Low power */
268		if (!(usbcfg & GUSBCFG_PHY_LP_CLK_SEL)) {
269			/* Set PHY low power clock select for FS/LS devices */
270			usbcfg |= GUSBCFG_PHY_LP_CLK_SEL;
271			writel(usbcfg, hsotg->regs + GUSBCFG);
272			do_reset = 1;
273		}
274
275		hcfg = readl(hsotg->regs + HCFG);
276		fslspclksel = (hcfg & HCFG_FSLSPCLKSEL_MASK) >>
277			      HCFG_FSLSPCLKSEL_SHIFT;
278
279		if (prtspd == HPRT0_SPD_LOW_SPEED &&
280		    params->host_ls_low_power_phy_clk ==
281		    DWC2_HOST_LS_LOW_POWER_PHY_CLK_PARAM_6MHZ) {
282			/* 6 MHZ */
283			dev_vdbg(hsotg->dev,
284				 "FS_PHY programming HCFG to 6 MHz\n");
285			if (fslspclksel != HCFG_FSLSPCLKSEL_6_MHZ) {
286				fslspclksel = HCFG_FSLSPCLKSEL_6_MHZ;
287				hcfg &= ~HCFG_FSLSPCLKSEL_MASK;
288				hcfg |= fslspclksel << HCFG_FSLSPCLKSEL_SHIFT;
289				writel(hcfg, hsotg->regs + HCFG);
290				do_reset = 1;
291			}
292		} else {
293			/* 48 MHZ */
294			dev_vdbg(hsotg->dev,
295				 "FS_PHY programming HCFG to 48 MHz\n");
296			if (fslspclksel != HCFG_FSLSPCLKSEL_48_MHZ) {
297				fslspclksel = HCFG_FSLSPCLKSEL_48_MHZ;
298				hcfg &= ~HCFG_FSLSPCLKSEL_MASK;
299				hcfg |= fslspclksel << HCFG_FSLSPCLKSEL_SHIFT;
300				writel(hcfg, hsotg->regs + HCFG);
301				do_reset = 1;
302			}
303		}
304	} else {
305		/* Not low power */
306		if (usbcfg & GUSBCFG_PHY_LP_CLK_SEL) {
307			usbcfg &= ~GUSBCFG_PHY_LP_CLK_SEL;
308			writel(usbcfg, hsotg->regs + GUSBCFG);
309			do_reset = 1;
310		}
311	}
312
313	if (do_reset) {
314		*hprt0_modify |= HPRT0_RST;
315		queue_delayed_work(hsotg->wq_otg, &hsotg->reset_work,
316				   msecs_to_jiffies(60));
317	} else {
318		/* Port has been enabled, set the reset change flag */
319		hsotg->flags.b.port_reset_change = 1;
320	}
321}
322
323/*
324 * There are multiple conditions that can cause a port interrupt. This function
325 * determines which interrupt conditions have occurred and handles them
326 * appropriately.
327 */
328static void dwc2_port_intr(struct dwc2_hsotg *hsotg)
329{
330	u32 hprt0;
331	u32 hprt0_modify;
332
333	dev_vdbg(hsotg->dev, "--Port Interrupt--\n");
334
335	hprt0 = readl(hsotg->regs + HPRT0);
336	hprt0_modify = hprt0;
337
338	/*
339	 * Clear appropriate bits in HPRT0 to clear the interrupt bit in
340	 * GINTSTS
341	 */
342	hprt0_modify &= ~(HPRT0_ENA | HPRT0_CONNDET | HPRT0_ENACHG |
343			  HPRT0_OVRCURRCHG);
344
345	/*
346	 * Port Connect Detected
347	 * Set flag and clear if detected
348	 */
349	if (hprt0 & HPRT0_CONNDET) {
350		dev_vdbg(hsotg->dev,
351			 "--Port Interrupt HPRT0=0x%08x Port Connect Detected--\n",
352			 hprt0);
353		hsotg->flags.b.port_connect_status_change = 1;
354		hsotg->flags.b.port_connect_status = 1;
355		hprt0_modify |= HPRT0_CONNDET;
356
357		/*
358		 * The Hub driver asserts a reset when it sees port connect
359		 * status change flag
360		 */
361	}
362
363	/*
364	 * Port Enable Changed
365	 * Clear if detected - Set internal flag if disabled
366	 */
367	if (hprt0 & HPRT0_ENACHG) {
368		dev_vdbg(hsotg->dev,
369			 "  --Port Interrupt HPRT0=0x%08x Port Enable Changed (now %d)--\n",
370			 hprt0, !!(hprt0 & HPRT0_ENA));
371		hprt0_modify |= HPRT0_ENACHG;
372		if (hprt0 & HPRT0_ENA)
373			dwc2_hprt0_enable(hsotg, hprt0, &hprt0_modify);
374		else
375			hsotg->flags.b.port_enable_change = 1;
376	}
377
378	/* Overcurrent Change Interrupt */
379	if (hprt0 & HPRT0_OVRCURRCHG) {
380		dev_vdbg(hsotg->dev,
381			 "  --Port Interrupt HPRT0=0x%08x Port Overcurrent Changed--\n",
382			 hprt0);
383		hsotg->flags.b.port_over_current_change = 1;
384		hprt0_modify |= HPRT0_OVRCURRCHG;
385	}
386
387	/* Clear Port Interrupts */
388	writel(hprt0_modify, hsotg->regs + HPRT0);
389}
390
391/*
392 * Gets the actual length of a transfer after the transfer halts. halt_status
393 * holds the reason for the halt.
394 *
395 * For IN transfers where halt_status is DWC2_HC_XFER_COMPLETE, *short_read
396 * is set to 1 upon return if less than the requested number of bytes were
397 * transferred. short_read may also be NULL on entry, in which case it remains
398 * unchanged.
399 */
400static u32 dwc2_get_actual_xfer_length(struct dwc2_hsotg *hsotg,
401				       struct dwc2_host_chan *chan, int chnum,
402				       struct dwc2_qtd *qtd,
403				       enum dwc2_halt_status halt_status,
404				       int *short_read)
405{
406	u32 hctsiz, count, length;
407
408	hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
409
410	if (halt_status == DWC2_HC_XFER_COMPLETE) {
411		if (chan->ep_is_in) {
412			count = (hctsiz & TSIZ_XFERSIZE_MASK) >>
413				TSIZ_XFERSIZE_SHIFT;
414			length = chan->xfer_len - count;
415			if (short_read != NULL)
416				*short_read = (count != 0);
417		} else if (chan->qh->do_split) {
418			length = qtd->ssplit_out_xfer_count;
419		} else {
420			length = chan->xfer_len;
421		}
422	} else {
423		/*
424		 * Must use the hctsiz.pktcnt field to determine how much data
425		 * has been transferred. This field reflects the number of
426		 * packets that have been transferred via the USB. This is
427		 * always an integral number of packets if the transfer was
428		 * halted before its normal completion. (Can't use the
429		 * hctsiz.xfersize field because that reflects the number of
430		 * bytes transferred via the AHB, not the USB).
431		 */
432		count = (hctsiz & TSIZ_PKTCNT_MASK) >> TSIZ_PKTCNT_SHIFT;
433		length = (chan->start_pkt_count - count) * chan->max_packet;
434	}
435
436	return length;
437}
438
439/**
440 * dwc2_update_urb_state() - Updates the state of the URB after a Transfer
441 * Complete interrupt on the host channel. Updates the actual_length field
442 * of the URB based on the number of bytes transferred via the host channel.
443 * Sets the URB status if the data transfer is finished.
444 *
445 * Return: 1 if the data transfer specified by the URB is completely finished,
446 * 0 otherwise
447 */
448static int dwc2_update_urb_state(struct dwc2_hsotg *hsotg,
449				 struct dwc2_host_chan *chan, int chnum,
450				 struct dwc2_hcd_urb *urb,
451				 struct dwc2_qtd *qtd)
452{
453	u32 hctsiz;
454	int xfer_done = 0;
455	int short_read = 0;
456	int xfer_length = dwc2_get_actual_xfer_length(hsotg, chan, chnum, qtd,
457						      DWC2_HC_XFER_COMPLETE,
458						      &short_read);
459
460	if (urb->actual_length + xfer_length > urb->length) {
461		dev_warn(hsotg->dev, "%s(): trimming xfer length\n", __func__);
462		xfer_length = urb->length - urb->actual_length;
463	}
464
465	/* Non DWORD-aligned buffer case handling */
466	if (chan->align_buf && xfer_length && chan->ep_is_in) {
467		dev_vdbg(hsotg->dev, "%s(): non-aligned buffer\n", __func__);
468		memcpy(urb->buf + urb->actual_length, chan->qh->dw_align_buf,
469		       xfer_length);
470	}
471
472	dev_vdbg(hsotg->dev, "urb->actual_length=%d xfer_length=%d\n",
473		 urb->actual_length, xfer_length);
474	urb->actual_length += xfer_length;
475
476	if (xfer_length && chan->ep_type == USB_ENDPOINT_XFER_BULK &&
477	    (urb->flags & URB_SEND_ZERO_PACKET) &&
478	    urb->actual_length >= urb->length &&
479	    !(urb->length % chan->max_packet)) {
480		xfer_done = 0;
481	} else if (short_read || urb->actual_length >= urb->length) {
482		xfer_done = 1;
483		urb->status = 0;
484	}
485
486	hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
487	dev_vdbg(hsotg->dev, "DWC_otg: %s: %s, channel %d\n",
488		 __func__, (chan->ep_is_in ? "IN" : "OUT"), chnum);
489	dev_vdbg(hsotg->dev, "  chan->xfer_len %d\n", chan->xfer_len);
490	dev_vdbg(hsotg->dev, "  hctsiz.xfersize %d\n",
491		 (hctsiz & TSIZ_XFERSIZE_MASK) >> TSIZ_XFERSIZE_SHIFT);
492	dev_vdbg(hsotg->dev, "  urb->transfer_buffer_length %d\n", urb->length);
493	dev_vdbg(hsotg->dev, "  urb->actual_length %d\n", urb->actual_length);
494	dev_vdbg(hsotg->dev, "  short_read %d, xfer_done %d\n", short_read,
495		 xfer_done);
496
497	return xfer_done;
498}
499
500/*
501 * Save the starting data toggle for the next transfer. The data toggle is
502 * saved in the QH for non-control transfers and it's saved in the QTD for
503 * control transfers.
504 */
505void dwc2_hcd_save_data_toggle(struct dwc2_hsotg *hsotg,
506			       struct dwc2_host_chan *chan, int chnum,
507			       struct dwc2_qtd *qtd)
508{
509	u32 hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
510	u32 pid = (hctsiz & TSIZ_SC_MC_PID_MASK) >> TSIZ_SC_MC_PID_SHIFT;
511
512	if (chan->ep_type != USB_ENDPOINT_XFER_CONTROL) {
513		if (pid == TSIZ_SC_MC_PID_DATA0)
514			chan->qh->data_toggle = DWC2_HC_PID_DATA0;
515		else
516			chan->qh->data_toggle = DWC2_HC_PID_DATA1;
517	} else {
518		if (pid == TSIZ_SC_MC_PID_DATA0)
519			qtd->data_toggle = DWC2_HC_PID_DATA0;
520		else
521			qtd->data_toggle = DWC2_HC_PID_DATA1;
522	}
523}
524
525/**
526 * dwc2_update_isoc_urb_state() - Updates the state of an Isochronous URB when
527 * the transfer is stopped for any reason. The fields of the current entry in
528 * the frame descriptor array are set based on the transfer state and the input
529 * halt_status. Completes the Isochronous URB if all the URB frames have been
530 * completed.
531 *
532 * Return: DWC2_HC_XFER_COMPLETE if there are more frames remaining to be
533 * transferred in the URB. Otherwise return DWC2_HC_XFER_URB_COMPLETE.
534 */
535static enum dwc2_halt_status dwc2_update_isoc_urb_state(
536		struct dwc2_hsotg *hsotg, struct dwc2_host_chan *chan,
537		int chnum, struct dwc2_qtd *qtd,
538		enum dwc2_halt_status halt_status)
539{
540	struct dwc2_hcd_iso_packet_desc *frame_desc;
541	struct dwc2_hcd_urb *urb = qtd->urb;
542
543	if (!urb)
544		return DWC2_HC_XFER_NO_HALT_STATUS;
545
546	frame_desc = &urb->iso_descs[qtd->isoc_frame_index];
547
548	switch (halt_status) {
549	case DWC2_HC_XFER_COMPLETE:
550		frame_desc->status = 0;
551		frame_desc->actual_length = dwc2_get_actual_xfer_length(hsotg,
552					chan, chnum, qtd, halt_status, NULL);
553
554		/* Non DWORD-aligned buffer case handling */
555		if (chan->align_buf && frame_desc->actual_length &&
556		    chan->ep_is_in) {
557			dev_vdbg(hsotg->dev, "%s(): non-aligned buffer\n",
558				 __func__);
559			memcpy(urb->buf + frame_desc->offset +
560			       qtd->isoc_split_offset, chan->qh->dw_align_buf,
561			       frame_desc->actual_length);
562		}
563		break;
564	case DWC2_HC_XFER_FRAME_OVERRUN:
565		urb->error_count++;
566		if (chan->ep_is_in)
567			frame_desc->status = -ENOSR;
568		else
569			frame_desc->status = -ECOMM;
570		frame_desc->actual_length = 0;
571		break;
572	case DWC2_HC_XFER_BABBLE_ERR:
573		urb->error_count++;
574		frame_desc->status = -EOVERFLOW;
575		/* Don't need to update actual_length in this case */
576		break;
577	case DWC2_HC_XFER_XACT_ERR:
578		urb->error_count++;
579		frame_desc->status = -EPROTO;
580		frame_desc->actual_length = dwc2_get_actual_xfer_length(hsotg,
581					chan, chnum, qtd, halt_status, NULL);
582
583		/* Non DWORD-aligned buffer case handling */
584		if (chan->align_buf && frame_desc->actual_length &&
585		    chan->ep_is_in) {
586			dev_vdbg(hsotg->dev, "%s(): non-aligned buffer\n",
587				 __func__);
588			memcpy(urb->buf + frame_desc->offset +
589			       qtd->isoc_split_offset, chan->qh->dw_align_buf,
590			       frame_desc->actual_length);
591		}
592
593		/* Skip whole frame */
594		if (chan->qh->do_split &&
595		    chan->ep_type == USB_ENDPOINT_XFER_ISOC && chan->ep_is_in &&
596		    hsotg->core_params->dma_enable > 0) {
597			qtd->complete_split = 0;
598			qtd->isoc_split_offset = 0;
599		}
600
601		break;
602	default:
603		dev_err(hsotg->dev, "Unhandled halt_status (%d)\n",
604			halt_status);
605		break;
606	}
607
608	if (++qtd->isoc_frame_index == urb->packet_count) {
609		/*
610		 * urb->status is not used for isoc transfers. The individual
611		 * frame_desc statuses are used instead.
612		 */
613		dwc2_host_complete(hsotg, qtd, 0);
614		halt_status = DWC2_HC_XFER_URB_COMPLETE;
615	} else {
616		halt_status = DWC2_HC_XFER_COMPLETE;
617	}
618
619	return halt_status;
620}
621
622/*
623 * Frees the first QTD in the QH's list if free_qtd is 1. For non-periodic
624 * QHs, removes the QH from the active non-periodic schedule. If any QTDs are
625 * still linked to the QH, the QH is added to the end of the inactive
626 * non-periodic schedule. For periodic QHs, removes the QH from the periodic
627 * schedule if no more QTDs are linked to the QH.
628 */
629static void dwc2_deactivate_qh(struct dwc2_hsotg *hsotg, struct dwc2_qh *qh,
630			       int free_qtd)
631{
632	int continue_split = 0;
633	struct dwc2_qtd *qtd;
634
635	if (dbg_qh(qh))
636		dev_vdbg(hsotg->dev, "  %s(%p,%p,%d)\n", __func__,
637			 hsotg, qh, free_qtd);
638
639	if (list_empty(&qh->qtd_list)) {
640		dev_dbg(hsotg->dev, "## QTD list empty ##\n");
641		goto no_qtd;
642	}
643
644	qtd = list_first_entry(&qh->qtd_list, struct dwc2_qtd, qtd_list_entry);
645
646	if (qtd->complete_split)
647		continue_split = 1;
648	else if (qtd->isoc_split_pos == DWC2_HCSPLT_XACTPOS_MID ||
649		 qtd->isoc_split_pos == DWC2_HCSPLT_XACTPOS_END)
650		continue_split = 1;
651
652	if (free_qtd) {
653		dwc2_hcd_qtd_unlink_and_free(hsotg, qtd, qh);
654		continue_split = 0;
655	}
656
657no_qtd:
658	if (qh->channel)
659		qh->channel->align_buf = 0;
660	qh->channel = NULL;
661	dwc2_hcd_qh_deactivate(hsotg, qh, continue_split);
662}
663
664/**
665 * dwc2_release_channel() - Releases a host channel for use by other transfers
666 *
667 * @hsotg:       The HCD state structure
668 * @chan:        The host channel to release
669 * @qtd:         The QTD associated with the host channel. This QTD may be
670 *               freed if the transfer is complete or an error has occurred.
671 * @halt_status: Reason the channel is being released. This status
672 *               determines the actions taken by this function.
673 *
674 * Also attempts to select and queue more transactions since at least one host
675 * channel is available.
676 */
677static void dwc2_release_channel(struct dwc2_hsotg *hsotg,
678				 struct dwc2_host_chan *chan,
679				 struct dwc2_qtd *qtd,
680				 enum dwc2_halt_status halt_status)
681{
682	enum dwc2_transaction_type tr_type;
683	u32 haintmsk;
684	int free_qtd = 0;
685
686	if (dbg_hc(chan))
687		dev_vdbg(hsotg->dev, "  %s: channel %d, halt_status %d\n",
688			 __func__, chan->hc_num, halt_status);
689
690	switch (halt_status) {
691	case DWC2_HC_XFER_URB_COMPLETE:
692		free_qtd = 1;
693		break;
694	case DWC2_HC_XFER_AHB_ERR:
695	case DWC2_HC_XFER_STALL:
696	case DWC2_HC_XFER_BABBLE_ERR:
697		free_qtd = 1;
698		break;
699	case DWC2_HC_XFER_XACT_ERR:
700		if (qtd && qtd->error_count >= 3) {
701			dev_vdbg(hsotg->dev,
702				 "  Complete URB with transaction error\n");
703			free_qtd = 1;
704			dwc2_host_complete(hsotg, qtd, -EPROTO);
705		}
706		break;
707	case DWC2_HC_XFER_URB_DEQUEUE:
708		/*
709		 * The QTD has already been removed and the QH has been
710		 * deactivated. Don't want to do anything except release the
711		 * host channel and try to queue more transfers.
712		 */
713		goto cleanup;
714	case DWC2_HC_XFER_PERIODIC_INCOMPLETE:
715		dev_vdbg(hsotg->dev, "  Complete URB with I/O error\n");
716		free_qtd = 1;
717		dwc2_host_complete(hsotg, qtd, -EIO);
718		break;
719	case DWC2_HC_XFER_NO_HALT_STATUS:
720	default:
721		break;
722	}
723
724	dwc2_deactivate_qh(hsotg, chan->qh, free_qtd);
725
726cleanup:
727	/*
728	 * Release the host channel for use by other transfers. The cleanup
729	 * function clears the channel interrupt enables and conditions, so
730	 * there's no need to clear the Channel Halted interrupt separately.
731	 */
732	if (!list_empty(&chan->hc_list_entry))
733		list_del(&chan->hc_list_entry);
734	dwc2_hc_cleanup(hsotg, chan);
735	list_add_tail(&chan->hc_list_entry, &hsotg->free_hc_list);
736
737	if (hsotg->core_params->uframe_sched > 0) {
738		hsotg->available_host_channels++;
739	} else {
740		switch (chan->ep_type) {
741		case USB_ENDPOINT_XFER_CONTROL:
742		case USB_ENDPOINT_XFER_BULK:
743			hsotg->non_periodic_channels--;
744			break;
745		default:
746			/*
747			 * Don't release reservations for periodic channels
748			 * here. That's done when a periodic transfer is
749			 * descheduled (i.e. when the QH is removed from the
750			 * periodic schedule).
751			 */
752			break;
753		}
754	}
755
756	haintmsk = readl(hsotg->regs + HAINTMSK);
757	haintmsk &= ~(1 << chan->hc_num);
758	writel(haintmsk, hsotg->regs + HAINTMSK);
759
760	/* Try to queue more transfers now that there's a free channel */
761	tr_type = dwc2_hcd_select_transactions(hsotg);
762	if (tr_type != DWC2_TRANSACTION_NONE)
763		dwc2_hcd_queue_transactions(hsotg, tr_type);
764}
765
766/*
767 * Halts a host channel. If the channel cannot be halted immediately because
768 * the request queue is full, this function ensures that the FIFO empty
769 * interrupt for the appropriate queue is enabled so that the halt request can
770 * be queued when there is space in the request queue.
771 *
772 * This function may also be called in DMA mode. In that case, the channel is
773 * simply released since the core always halts the channel automatically in
774 * DMA mode.
775 */
776static void dwc2_halt_channel(struct dwc2_hsotg *hsotg,
777			      struct dwc2_host_chan *chan, struct dwc2_qtd *qtd,
778			      enum dwc2_halt_status halt_status)
779{
780	if (dbg_hc(chan))
781		dev_vdbg(hsotg->dev, "%s()\n", __func__);
782
783	if (hsotg->core_params->dma_enable > 0) {
784		if (dbg_hc(chan))
785			dev_vdbg(hsotg->dev, "DMA enabled\n");
786		dwc2_release_channel(hsotg, chan, qtd, halt_status);
787		return;
788	}
789
790	/* Slave mode processing */
791	dwc2_hc_halt(hsotg, chan, halt_status);
792
793	if (chan->halt_on_queue) {
794		u32 gintmsk;
795
796		dev_vdbg(hsotg->dev, "Halt on queue\n");
797		if (chan->ep_type == USB_ENDPOINT_XFER_CONTROL ||
798		    chan->ep_type == USB_ENDPOINT_XFER_BULK) {
799			dev_vdbg(hsotg->dev, "control/bulk\n");
800			/*
801			 * Make sure the Non-periodic Tx FIFO empty interrupt
802			 * is enabled so that the non-periodic schedule will
803			 * be processed
804			 */
805			gintmsk = readl(hsotg->regs + GINTMSK);
806			gintmsk |= GINTSTS_NPTXFEMP;
807			writel(gintmsk, hsotg->regs + GINTMSK);
808		} else {
809			dev_vdbg(hsotg->dev, "isoc/intr\n");
810			/*
811			 * Move the QH from the periodic queued schedule to
812			 * the periodic assigned schedule. This allows the
813			 * halt to be queued when the periodic schedule is
814			 * processed.
815			 */
816			list_move(&chan->qh->qh_list_entry,
817				  &hsotg->periodic_sched_assigned);
818
819			/*
820			 * Make sure the Periodic Tx FIFO Empty interrupt is
821			 * enabled so that the periodic schedule will be
822			 * processed
823			 */
824			gintmsk = readl(hsotg->regs + GINTMSK);
825			gintmsk |= GINTSTS_PTXFEMP;
826			writel(gintmsk, hsotg->regs + GINTMSK);
827		}
828	}
829}
830
831/*
832 * Performs common cleanup for non-periodic transfers after a Transfer
833 * Complete interrupt. This function should be called after any endpoint type
834 * specific handling is finished to release the host channel.
835 */
836static void dwc2_complete_non_periodic_xfer(struct dwc2_hsotg *hsotg,
837					    struct dwc2_host_chan *chan,
838					    int chnum, struct dwc2_qtd *qtd,
839					    enum dwc2_halt_status halt_status)
840{
841	dev_vdbg(hsotg->dev, "%s()\n", __func__);
842
843	qtd->error_count = 0;
844
845	if (chan->hcint & HCINTMSK_NYET) {
846		/*
847		 * Got a NYET on the last transaction of the transfer. This
848		 * means that the endpoint should be in the PING state at the
849		 * beginning of the next transfer.
850		 */
851		dev_vdbg(hsotg->dev, "got NYET\n");
852		chan->qh->ping_state = 1;
853	}
854
855	/*
856	 * Always halt and release the host channel to make it available for
857	 * more transfers. There may still be more phases for a control
858	 * transfer or more data packets for a bulk transfer at this point,
859	 * but the host channel is still halted. A channel will be reassigned
860	 * to the transfer when the non-periodic schedule is processed after
861	 * the channel is released. This allows transactions to be queued
862	 * properly via dwc2_hcd_queue_transactions, which also enables the
863	 * Tx FIFO Empty interrupt if necessary.
864	 */
865	if (chan->ep_is_in) {
866		/*
867		 * IN transfers in Slave mode require an explicit disable to
868		 * halt the channel. (In DMA mode, this call simply releases
869		 * the channel.)
870		 */
871		dwc2_halt_channel(hsotg, chan, qtd, halt_status);
872	} else {
873		/*
874		 * The channel is automatically disabled by the core for OUT
875		 * transfers in Slave mode
876		 */
877		dwc2_release_channel(hsotg, chan, qtd, halt_status);
878	}
879}
880
881/*
882 * Performs common cleanup for periodic transfers after a Transfer Complete
883 * interrupt. This function should be called after any endpoint type specific
884 * handling is finished to release the host channel.
885 */
886static void dwc2_complete_periodic_xfer(struct dwc2_hsotg *hsotg,
887					struct dwc2_host_chan *chan, int chnum,
888					struct dwc2_qtd *qtd,
889					enum dwc2_halt_status halt_status)
890{
891	u32 hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
892
893	qtd->error_count = 0;
894
895	if (!chan->ep_is_in || (hctsiz & TSIZ_PKTCNT_MASK) == 0)
896		/* Core halts channel in these cases */
897		dwc2_release_channel(hsotg, chan, qtd, halt_status);
898	else
899		/* Flush any outstanding requests from the Tx queue */
900		dwc2_halt_channel(hsotg, chan, qtd, halt_status);
901}
902
903static int dwc2_xfercomp_isoc_split_in(struct dwc2_hsotg *hsotg,
904				       struct dwc2_host_chan *chan, int chnum,
905				       struct dwc2_qtd *qtd)
906{
907	struct dwc2_hcd_iso_packet_desc *frame_desc;
908	u32 len;
909
910	if (!qtd->urb)
911		return 0;
912
913	frame_desc = &qtd->urb->iso_descs[qtd->isoc_frame_index];
914	len = dwc2_get_actual_xfer_length(hsotg, chan, chnum, qtd,
915					  DWC2_HC_XFER_COMPLETE, NULL);
916	if (!len) {
917		qtd->complete_split = 0;
918		qtd->isoc_split_offset = 0;
919		return 0;
920	}
921
922	frame_desc->actual_length += len;
923
924	if (chan->align_buf) {
925		dev_vdbg(hsotg->dev, "%s(): non-aligned buffer\n", __func__);
926		memcpy(qtd->urb->buf + frame_desc->offset +
927		       qtd->isoc_split_offset, chan->qh->dw_align_buf, len);
928	}
929
930	qtd->isoc_split_offset += len;
931
932	if (frame_desc->actual_length >= frame_desc->length) {
933		frame_desc->status = 0;
934		qtd->isoc_frame_index++;
935		qtd->complete_split = 0;
936		qtd->isoc_split_offset = 0;
937	}
938
939	if (qtd->isoc_frame_index == qtd->urb->packet_count) {
940		dwc2_host_complete(hsotg, qtd, 0);
941		dwc2_release_channel(hsotg, chan, qtd,
942				     DWC2_HC_XFER_URB_COMPLETE);
943	} else {
944		dwc2_release_channel(hsotg, chan, qtd,
945				     DWC2_HC_XFER_NO_HALT_STATUS);
946	}
947
948	return 1;	/* Indicates that channel released */
949}
950
951/*
952 * Handles a host channel Transfer Complete interrupt. This handler may be
953 * called in either DMA mode or Slave mode.
954 */
955static void dwc2_hc_xfercomp_intr(struct dwc2_hsotg *hsotg,
956				  struct dwc2_host_chan *chan, int chnum,
957				  struct dwc2_qtd *qtd)
958{
959	struct dwc2_hcd_urb *urb = qtd->urb;
960	enum dwc2_halt_status halt_status = DWC2_HC_XFER_COMPLETE;
961	int pipe_type;
962	int urb_xfer_done;
963
964	if (dbg_hc(chan))
965		dev_vdbg(hsotg->dev,
966			 "--Host Channel %d Interrupt: Transfer Complete--\n",
967			 chnum);
968
969	if (!urb)
970		goto handle_xfercomp_done;
971
972	pipe_type = dwc2_hcd_get_pipe_type(&urb->pipe_info);
973
974	if (hsotg->core_params->dma_desc_enable > 0) {
975		dwc2_hcd_complete_xfer_ddma(hsotg, chan, chnum, halt_status);
976		if (pipe_type == USB_ENDPOINT_XFER_ISOC)
977			/* Do not disable the interrupt, just clear it */
978			return;
979		goto handle_xfercomp_done;
980	}
981
982	/* Handle xfer complete on CSPLIT */
983	if (chan->qh->do_split) {
984		if (chan->ep_type == USB_ENDPOINT_XFER_ISOC && chan->ep_is_in &&
985		    hsotg->core_params->dma_enable > 0) {
986			if (qtd->complete_split &&
987			    dwc2_xfercomp_isoc_split_in(hsotg, chan, chnum,
988							qtd))
989				goto handle_xfercomp_done;
990		} else {
991			qtd->complete_split = 0;
992		}
993	}
994
995	/* Update the QTD and URB states */
996	switch (pipe_type) {
997	case USB_ENDPOINT_XFER_CONTROL:
998		switch (qtd->control_phase) {
999		case DWC2_CONTROL_SETUP:
1000			if (urb->length > 0)
1001				qtd->control_phase = DWC2_CONTROL_DATA;
1002			else
1003				qtd->control_phase = DWC2_CONTROL_STATUS;
1004			dev_vdbg(hsotg->dev,
1005				 "  Control setup transaction done\n");
1006			halt_status = DWC2_HC_XFER_COMPLETE;
1007			break;
1008		case DWC2_CONTROL_DATA:
1009			urb_xfer_done = dwc2_update_urb_state(hsotg, chan,
1010							      chnum, urb, qtd);
1011			if (urb_xfer_done) {
1012				qtd->control_phase = DWC2_CONTROL_STATUS;
1013				dev_vdbg(hsotg->dev,
1014					 "  Control data transfer done\n");
1015			} else {
1016				dwc2_hcd_save_data_toggle(hsotg, chan, chnum,
1017							  qtd);
1018			}
1019			halt_status = DWC2_HC_XFER_COMPLETE;
1020			break;
1021		case DWC2_CONTROL_STATUS:
1022			dev_vdbg(hsotg->dev, "  Control transfer complete\n");
1023			if (urb->status == -EINPROGRESS)
1024				urb->status = 0;
1025			dwc2_host_complete(hsotg, qtd, urb->status);
1026			halt_status = DWC2_HC_XFER_URB_COMPLETE;
1027			break;
1028		}
1029
1030		dwc2_complete_non_periodic_xfer(hsotg, chan, chnum, qtd,
1031						halt_status);
1032		break;
1033	case USB_ENDPOINT_XFER_BULK:
1034		dev_vdbg(hsotg->dev, "  Bulk transfer complete\n");
1035		urb_xfer_done = dwc2_update_urb_state(hsotg, chan, chnum, urb,
1036						      qtd);
1037		if (urb_xfer_done) {
1038			dwc2_host_complete(hsotg, qtd, urb->status);
1039			halt_status = DWC2_HC_XFER_URB_COMPLETE;
1040		} else {
1041			halt_status = DWC2_HC_XFER_COMPLETE;
1042		}
1043
1044		dwc2_hcd_save_data_toggle(hsotg, chan, chnum, qtd);
1045		dwc2_complete_non_periodic_xfer(hsotg, chan, chnum, qtd,
1046						halt_status);
1047		break;
1048	case USB_ENDPOINT_XFER_INT:
1049		dev_vdbg(hsotg->dev, "  Interrupt transfer complete\n");
1050		urb_xfer_done = dwc2_update_urb_state(hsotg, chan, chnum, urb,
1051						      qtd);
1052
1053		/*
1054		 * Interrupt URB is done on the first transfer complete
1055		 * interrupt
1056		 */
1057		if (urb_xfer_done) {
1058			dwc2_host_complete(hsotg, qtd, urb->status);
1059			halt_status = DWC2_HC_XFER_URB_COMPLETE;
1060		} else {
1061			halt_status = DWC2_HC_XFER_COMPLETE;
1062		}
1063
1064		dwc2_hcd_save_data_toggle(hsotg, chan, chnum, qtd);
1065		dwc2_complete_periodic_xfer(hsotg, chan, chnum, qtd,
1066					    halt_status);
1067		break;
1068	case USB_ENDPOINT_XFER_ISOC:
1069		if (dbg_perio())
1070			dev_vdbg(hsotg->dev, "  Isochronous transfer complete\n");
1071		if (qtd->isoc_split_pos == DWC2_HCSPLT_XACTPOS_ALL)
1072			halt_status = dwc2_update_isoc_urb_state(hsotg, chan,
1073					chnum, qtd, DWC2_HC_XFER_COMPLETE);
1074		dwc2_complete_periodic_xfer(hsotg, chan, chnum, qtd,
1075					    halt_status);
1076		break;
1077	}
1078
1079handle_xfercomp_done:
1080	disable_hc_int(hsotg, chnum, HCINTMSK_XFERCOMPL);
1081}
1082
1083/*
1084 * Handles a host channel STALL interrupt. This handler may be called in
1085 * either DMA mode or Slave mode.
1086 */
1087static void dwc2_hc_stall_intr(struct dwc2_hsotg *hsotg,
1088			       struct dwc2_host_chan *chan, int chnum,
1089			       struct dwc2_qtd *qtd)
1090{
1091	struct dwc2_hcd_urb *urb = qtd->urb;
1092	int pipe_type;
1093
1094	dev_dbg(hsotg->dev, "--Host Channel %d Interrupt: STALL Received--\n",
1095		chnum);
1096
1097	if (hsotg->core_params->dma_desc_enable > 0) {
1098		dwc2_hcd_complete_xfer_ddma(hsotg, chan, chnum,
1099					    DWC2_HC_XFER_STALL);
1100		goto handle_stall_done;
1101	}
1102
1103	if (!urb)
1104		goto handle_stall_halt;
1105
1106	pipe_type = dwc2_hcd_get_pipe_type(&urb->pipe_info);
1107
1108	if (pipe_type == USB_ENDPOINT_XFER_CONTROL)
1109		dwc2_host_complete(hsotg, qtd, -EPIPE);
1110
1111	if (pipe_type == USB_ENDPOINT_XFER_BULK ||
1112	    pipe_type == USB_ENDPOINT_XFER_INT) {
1113		dwc2_host_complete(hsotg, qtd, -EPIPE);
1114		/*
1115		 * USB protocol requires resetting the data toggle for bulk
1116		 * and interrupt endpoints when a CLEAR_FEATURE(ENDPOINT_HALT)
1117		 * setup command is issued to the endpoint. Anticipate the
1118		 * CLEAR_FEATURE command since a STALL has occurred and reset
1119		 * the data toggle now.
1120		 */
1121		chan->qh->data_toggle = 0;
1122	}
1123
1124handle_stall_halt:
1125	dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_STALL);
1126
1127handle_stall_done:
1128	disable_hc_int(hsotg, chnum, HCINTMSK_STALL);
1129}
1130
1131/*
1132 * Updates the state of the URB when a transfer has been stopped due to an
1133 * abnormal condition before the transfer completes. Modifies the
1134 * actual_length field of the URB to reflect the number of bytes that have
1135 * actually been transferred via the host channel.
1136 */
1137static void dwc2_update_urb_state_abn(struct dwc2_hsotg *hsotg,
1138				      struct dwc2_host_chan *chan, int chnum,
1139				      struct dwc2_hcd_urb *urb,
1140				      struct dwc2_qtd *qtd,
1141				      enum dwc2_halt_status halt_status)
1142{
1143	u32 xfer_length = dwc2_get_actual_xfer_length(hsotg, chan, chnum,
1144						      qtd, halt_status, NULL);
1145	u32 hctsiz;
1146
1147	if (urb->actual_length + xfer_length > urb->length) {
1148		dev_warn(hsotg->dev, "%s(): trimming xfer length\n", __func__);
1149		xfer_length = urb->length - urb->actual_length;
1150	}
1151
1152	/* Non DWORD-aligned buffer case handling */
1153	if (chan->align_buf && xfer_length && chan->ep_is_in) {
1154		dev_vdbg(hsotg->dev, "%s(): non-aligned buffer\n", __func__);
1155		memcpy(urb->buf + urb->actual_length, chan->qh->dw_align_buf,
1156		       xfer_length);
1157	}
1158
1159	urb->actual_length += xfer_length;
1160
1161	hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
1162	dev_vdbg(hsotg->dev, "DWC_otg: %s: %s, channel %d\n",
1163		 __func__, (chan->ep_is_in ? "IN" : "OUT"), chnum);
1164	dev_vdbg(hsotg->dev, "  chan->start_pkt_count %d\n",
1165		 chan->start_pkt_count);
1166	dev_vdbg(hsotg->dev, "  hctsiz.pktcnt %d\n",
1167		 (hctsiz & TSIZ_PKTCNT_MASK) >> TSIZ_PKTCNT_SHIFT);
1168	dev_vdbg(hsotg->dev, "  chan->max_packet %d\n", chan->max_packet);
1169	dev_vdbg(hsotg->dev, "  bytes_transferred %d\n",
1170		 xfer_length);
1171	dev_vdbg(hsotg->dev, "  urb->actual_length %d\n",
1172		 urb->actual_length);
1173	dev_vdbg(hsotg->dev, "  urb->transfer_buffer_length %d\n",
1174		 urb->length);
1175}
1176
1177/*
1178 * Handles a host channel NAK interrupt. This handler may be called in either
1179 * DMA mode or Slave mode.
1180 */
1181static void dwc2_hc_nak_intr(struct dwc2_hsotg *hsotg,
1182			     struct dwc2_host_chan *chan, int chnum,
1183			     struct dwc2_qtd *qtd)
1184{
1185	if (dbg_hc(chan))
1186		dev_vdbg(hsotg->dev, "--Host Channel %d Interrupt: NAK Received--\n",
1187			 chnum);
1188
1189	/*
1190	 * Handle NAK for IN/OUT SSPLIT/CSPLIT transfers, bulk, control, and
1191	 * interrupt. Re-start the SSPLIT transfer.
1192	 */
1193	if (chan->do_split) {
1194		if (chan->complete_split)
1195			qtd->error_count = 0;
1196		qtd->complete_split = 0;
1197		dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_NAK);
1198		goto handle_nak_done;
1199	}
1200
1201	switch (dwc2_hcd_get_pipe_type(&qtd->urb->pipe_info)) {
1202	case USB_ENDPOINT_XFER_CONTROL:
1203	case USB_ENDPOINT_XFER_BULK:
1204		if (hsotg->core_params->dma_enable > 0 && chan->ep_is_in) {
1205			/*
1206			 * NAK interrupts are enabled on bulk/control IN
1207			 * transfers in DMA mode for the sole purpose of
1208			 * resetting the error count after a transaction error
1209			 * occurs. The core will continue transferring data.
1210			 */
1211			qtd->error_count = 0;
1212			break;
1213		}
1214
1215		/*
1216		 * NAK interrupts normally occur during OUT transfers in DMA
1217		 * or Slave mode. For IN transfers, more requests will be
1218		 * queued as request queue space is available.
1219		 */
1220		qtd->error_count = 0;
1221
1222		if (!chan->qh->ping_state) {
1223			dwc2_update_urb_state_abn(hsotg, chan, chnum, qtd->urb,
1224						  qtd, DWC2_HC_XFER_NAK);
1225			dwc2_hcd_save_data_toggle(hsotg, chan, chnum, qtd);
1226
1227			if (chan->speed == USB_SPEED_HIGH)
1228				chan->qh->ping_state = 1;
1229		}
1230
1231		/*
1232		 * Halt the channel so the transfer can be re-started from
1233		 * the appropriate point or the PING protocol will
1234		 * start/continue
1235		 */
1236		dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_NAK);
1237		break;
1238	case USB_ENDPOINT_XFER_INT:
1239		qtd->error_count = 0;
1240		dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_NAK);
1241		break;
1242	case USB_ENDPOINT_XFER_ISOC:
1243		/* Should never get called for isochronous transfers */
1244		dev_err(hsotg->dev, "NACK interrupt for ISOC transfer\n");
1245		break;
1246	}
1247
1248handle_nak_done:
1249	disable_hc_int(hsotg, chnum, HCINTMSK_NAK);
1250}
1251
1252/*
1253 * Handles a host channel ACK interrupt. This interrupt is enabled when
1254 * performing the PING protocol in Slave mode, when errors occur during
1255 * either Slave mode or DMA mode, and during Start Split transactions.
1256 */
1257static void dwc2_hc_ack_intr(struct dwc2_hsotg *hsotg,
1258			     struct dwc2_host_chan *chan, int chnum,
1259			     struct dwc2_qtd *qtd)
1260{
1261	struct dwc2_hcd_iso_packet_desc *frame_desc;
1262
1263	if (dbg_hc(chan))
1264		dev_vdbg(hsotg->dev, "--Host Channel %d Interrupt: ACK Received--\n",
1265			 chnum);
1266
1267	if (chan->do_split) {
1268		/* Handle ACK on SSPLIT. ACK should not occur in CSPLIT. */
1269		if (!chan->ep_is_in &&
1270		    chan->data_pid_start != DWC2_HC_PID_SETUP)
1271			qtd->ssplit_out_xfer_count = chan->xfer_len;
1272
1273		if (chan->ep_type != USB_ENDPOINT_XFER_ISOC || chan->ep_is_in) {
1274			qtd->complete_split = 1;
1275			dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_ACK);
1276		} else {
1277			/* ISOC OUT */
1278			switch (chan->xact_pos) {
1279			case DWC2_HCSPLT_XACTPOS_ALL:
1280				break;
1281			case DWC2_HCSPLT_XACTPOS_END:
1282				qtd->isoc_split_pos = DWC2_HCSPLT_XACTPOS_ALL;
1283				qtd->isoc_split_offset = 0;
1284				break;
1285			case DWC2_HCSPLT_XACTPOS_BEGIN:
1286			case DWC2_HCSPLT_XACTPOS_MID:
1287				/*
1288				 * For BEGIN or MID, calculate the length for
1289				 * the next microframe to determine the correct
1290				 * SSPLIT token, either MID or END
1291				 */
1292				frame_desc = &qtd->urb->iso_descs[
1293						qtd->isoc_frame_index];
1294				qtd->isoc_split_offset += 188;
1295
1296				if (frame_desc->length - qtd->isoc_split_offset
1297							<= 188)
1298					qtd->isoc_split_pos =
1299							DWC2_HCSPLT_XACTPOS_END;
1300				else
1301					qtd->isoc_split_pos =
1302							DWC2_HCSPLT_XACTPOS_MID;
1303				break;
1304			}
1305		}
1306	} else {
1307		qtd->error_count = 0;
1308
1309		if (chan->qh->ping_state) {
1310			chan->qh->ping_state = 0;
1311			/*
1312			 * Halt the channel so the transfer can be re-started
1313			 * from the appropriate point. This only happens in
1314			 * Slave mode. In DMA mode, the ping_state is cleared
1315			 * when the transfer is started because the core
1316			 * automatically executes the PING, then the transfer.
1317			 */
1318			dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_ACK);
1319		}
1320	}
1321
1322	/*
1323	 * If the ACK occurred when _not_ in the PING state, let the channel
1324	 * continue transferring data after clearing the error count
1325	 */
1326	disable_hc_int(hsotg, chnum, HCINTMSK_ACK);
1327}
1328
1329/*
1330 * Handles a host channel NYET interrupt. This interrupt should only occur on
1331 * Bulk and Control OUT endpoints and for complete split transactions. If a
1332 * NYET occurs at the same time as a Transfer Complete interrupt, it is
1333 * handled in the xfercomp interrupt handler, not here. This handler may be
1334 * called in either DMA mode or Slave mode.
1335 */
1336static void dwc2_hc_nyet_intr(struct dwc2_hsotg *hsotg,
1337			      struct dwc2_host_chan *chan, int chnum,
1338			      struct dwc2_qtd *qtd)
1339{
1340	if (dbg_hc(chan))
1341		dev_vdbg(hsotg->dev, "--Host Channel %d Interrupt: NYET Received--\n",
1342			 chnum);
1343
1344	/*
1345	 * NYET on CSPLIT
1346	 * re-do the CSPLIT immediately on non-periodic
1347	 */
1348	if (chan->do_split && chan->complete_split) {
1349		if (chan->ep_is_in && chan->ep_type == USB_ENDPOINT_XFER_ISOC &&
1350		    hsotg->core_params->dma_enable > 0) {
1351			qtd->complete_split = 0;
1352			qtd->isoc_split_offset = 0;
1353			qtd->isoc_frame_index++;
1354			if (qtd->urb &&
1355			    qtd->isoc_frame_index == qtd->urb->packet_count) {
1356				dwc2_host_complete(hsotg, qtd, 0);
1357				dwc2_release_channel(hsotg, chan, qtd,
1358						     DWC2_HC_XFER_URB_COMPLETE);
1359			} else {
1360				dwc2_release_channel(hsotg, chan, qtd,
1361						DWC2_HC_XFER_NO_HALT_STATUS);
1362			}
1363			goto handle_nyet_done;
1364		}
1365
1366		if (chan->ep_type == USB_ENDPOINT_XFER_INT ||
1367		    chan->ep_type == USB_ENDPOINT_XFER_ISOC) {
1368			int frnum = dwc2_hcd_get_frame_number(hsotg);
1369
1370			if (dwc2_full_frame_num(frnum) !=
1371			    dwc2_full_frame_num(chan->qh->sched_frame)) {
1372				/*
1373				 * No longer in the same full speed frame.
1374				 * Treat this as a transaction error.
1375				 */
1376#if 0
1377				/*
1378				 * Todo: Fix system performance so this can
1379				 * be treated as an error. Right now complete
1380				 * splits cannot be scheduled precisely enough
1381				 * due to other system activity, so this error
1382				 * occurs regularly in Slave mode.
1383				 */
1384				qtd->error_count++;
1385#endif
1386				qtd->complete_split = 0;
1387				dwc2_halt_channel(hsotg, chan, qtd,
1388						  DWC2_HC_XFER_XACT_ERR);
1389				/* Todo: add support for isoc release */
1390				goto handle_nyet_done;
1391			}
1392		}
1393
1394		dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_NYET);
1395		goto handle_nyet_done;
1396	}
1397
1398	chan->qh->ping_state = 1;
1399	qtd->error_count = 0;
1400
1401	dwc2_update_urb_state_abn(hsotg, chan, chnum, qtd->urb, qtd,
1402				  DWC2_HC_XFER_NYET);
1403	dwc2_hcd_save_data_toggle(hsotg, chan, chnum, qtd);
1404
1405	/*
1406	 * Halt the channel and re-start the transfer so the PING protocol
1407	 * will start
1408	 */
1409	dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_NYET);
1410
1411handle_nyet_done:
1412	disable_hc_int(hsotg, chnum, HCINTMSK_NYET);
1413}
1414
1415/*
1416 * Handles a host channel babble interrupt. This handler may be called in
1417 * either DMA mode or Slave mode.
1418 */
1419static void dwc2_hc_babble_intr(struct dwc2_hsotg *hsotg,
1420				struct dwc2_host_chan *chan, int chnum,
1421				struct dwc2_qtd *qtd)
1422{
1423	dev_dbg(hsotg->dev, "--Host Channel %d Interrupt: Babble Error--\n",
1424		chnum);
1425
1426	dwc2_hc_handle_tt_clear(hsotg, chan, qtd);
1427
1428	if (hsotg->core_params->dma_desc_enable > 0) {
1429		dwc2_hcd_complete_xfer_ddma(hsotg, chan, chnum,
1430					    DWC2_HC_XFER_BABBLE_ERR);
1431		goto disable_int;
1432	}
1433
1434	if (chan->ep_type != USB_ENDPOINT_XFER_ISOC) {
1435		dwc2_host_complete(hsotg, qtd, -EOVERFLOW);
1436		dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_BABBLE_ERR);
1437	} else {
1438		enum dwc2_halt_status halt_status;
1439
1440		halt_status = dwc2_update_isoc_urb_state(hsotg, chan, chnum,
1441						qtd, DWC2_HC_XFER_BABBLE_ERR);
1442		dwc2_halt_channel(hsotg, chan, qtd, halt_status);
1443	}
1444
1445disable_int:
1446	disable_hc_int(hsotg, chnum, HCINTMSK_BBLERR);
1447}
1448
1449/*
1450 * Handles a host channel AHB error interrupt. This handler is only called in
1451 * DMA mode.
1452 */
1453static void dwc2_hc_ahberr_intr(struct dwc2_hsotg *hsotg,
1454				struct dwc2_host_chan *chan, int chnum,
1455				struct dwc2_qtd *qtd)
1456{
1457	struct dwc2_hcd_urb *urb = qtd->urb;
1458	char *pipetype, *speed;
1459	u32 hcchar;
1460	u32 hcsplt;
1461	u32 hctsiz;
1462	u32 hc_dma;
1463
1464	dev_dbg(hsotg->dev, "--Host Channel %d Interrupt: AHB Error--\n",
1465		chnum);
1466
1467	if (!urb)
1468		goto handle_ahberr_halt;
1469
1470	dwc2_hc_handle_tt_clear(hsotg, chan, qtd);
1471
1472	hcchar = readl(hsotg->regs + HCCHAR(chnum));
1473	hcsplt = readl(hsotg->regs + HCSPLT(chnum));
1474	hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
1475	hc_dma = readl(hsotg->regs + HCDMA(chnum));
1476
1477	dev_err(hsotg->dev, "AHB ERROR, Channel %d\n", chnum);
1478	dev_err(hsotg->dev, "  hcchar 0x%08x, hcsplt 0x%08x\n", hcchar, hcsplt);
1479	dev_err(hsotg->dev, "  hctsiz 0x%08x, hc_dma 0x%08x\n", hctsiz, hc_dma);
1480	dev_err(hsotg->dev, "  Device address: %d\n",
1481		dwc2_hcd_get_dev_addr(&urb->pipe_info));
1482	dev_err(hsotg->dev, "  Endpoint: %d, %s\n",
1483		dwc2_hcd_get_ep_num(&urb->pipe_info),
1484		dwc2_hcd_is_pipe_in(&urb->pipe_info) ? "IN" : "OUT");
1485
1486	switch (dwc2_hcd_get_pipe_type(&urb->pipe_info)) {
1487	case USB_ENDPOINT_XFER_CONTROL:
1488		pipetype = "CONTROL";
1489		break;
1490	case USB_ENDPOINT_XFER_BULK:
1491		pipetype = "BULK";
1492		break;
1493	case USB_ENDPOINT_XFER_INT:
1494		pipetype = "INTERRUPT";
1495		break;
1496	case USB_ENDPOINT_XFER_ISOC:
1497		pipetype = "ISOCHRONOUS";
1498		break;
1499	default:
1500		pipetype = "UNKNOWN";
1501		break;
1502	}
1503
1504	dev_err(hsotg->dev, "  Endpoint type: %s\n", pipetype);
1505
1506	switch (chan->speed) {
1507	case USB_SPEED_HIGH:
1508		speed = "HIGH";
1509		break;
1510	case USB_SPEED_FULL:
1511		speed = "FULL";
1512		break;
1513	case USB_SPEED_LOW:
1514		speed = "LOW";
1515		break;
1516	default:
1517		speed = "UNKNOWN";
1518		break;
1519	}
1520
1521	dev_err(hsotg->dev, "  Speed: %s\n", speed);
1522
1523	dev_err(hsotg->dev, "  Max packet size: %d\n",
1524		dwc2_hcd_get_mps(&urb->pipe_info));
1525	dev_err(hsotg->dev, "  Data buffer length: %d\n", urb->length);
1526	dev_err(hsotg->dev, "  Transfer buffer: %p, Transfer DMA: %08lx\n",
1527		urb->buf, (unsigned long)urb->dma);
1528	dev_err(hsotg->dev, "  Setup buffer: %p, Setup DMA: %08lx\n",
1529		urb->setup_packet, (unsigned long)urb->setup_dma);
1530	dev_err(hsotg->dev, "  Interval: %d\n", urb->interval);
1531
1532	/* Core halts the channel for Descriptor DMA mode */
1533	if (hsotg->core_params->dma_desc_enable > 0) {
1534		dwc2_hcd_complete_xfer_ddma(hsotg, chan, chnum,
1535					    DWC2_HC_XFER_AHB_ERR);
1536		goto handle_ahberr_done;
1537	}
1538
1539	dwc2_host_complete(hsotg, qtd, -EIO);
1540
1541handle_ahberr_halt:
1542	/*
1543	 * Force a channel halt. Don't call dwc2_halt_channel because that won't
1544	 * write to the HCCHARn register in DMA mode to force the halt.
1545	 */
1546	dwc2_hc_halt(hsotg, chan, DWC2_HC_XFER_AHB_ERR);
1547
1548handle_ahberr_done:
1549	disable_hc_int(hsotg, chnum, HCINTMSK_AHBERR);
1550}
1551
1552/*
1553 * Handles a host channel transaction error interrupt. This handler may be
1554 * called in either DMA mode or Slave mode.
1555 */
1556static void dwc2_hc_xacterr_intr(struct dwc2_hsotg *hsotg,
1557				 struct dwc2_host_chan *chan, int chnum,
1558				 struct dwc2_qtd *qtd)
1559{
1560	dev_dbg(hsotg->dev,
1561		"--Host Channel %d Interrupt: Transaction Error--\n", chnum);
1562
1563	dwc2_hc_handle_tt_clear(hsotg, chan, qtd);
1564
1565	if (hsotg->core_params->dma_desc_enable > 0) {
1566		dwc2_hcd_complete_xfer_ddma(hsotg, chan, chnum,
1567					    DWC2_HC_XFER_XACT_ERR);
1568		goto handle_xacterr_done;
1569	}
1570
1571	switch (dwc2_hcd_get_pipe_type(&qtd->urb->pipe_info)) {
1572	case USB_ENDPOINT_XFER_CONTROL:
1573	case USB_ENDPOINT_XFER_BULK:
1574		qtd->error_count++;
1575		if (!chan->qh->ping_state) {
1576
1577			dwc2_update_urb_state_abn(hsotg, chan, chnum, qtd->urb,
1578						  qtd, DWC2_HC_XFER_XACT_ERR);
1579			dwc2_hcd_save_data_toggle(hsotg, chan, chnum, qtd);
1580			if (!chan->ep_is_in && chan->speed == USB_SPEED_HIGH)
1581				chan->qh->ping_state = 1;
1582		}
1583
1584		/*
1585		 * Halt the channel so the transfer can be re-started from
1586		 * the appropriate point or the PING protocol will start
1587		 */
1588		dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_XACT_ERR);
1589		break;
1590	case USB_ENDPOINT_XFER_INT:
1591		qtd->error_count++;
1592		if (chan->do_split && chan->complete_split)
1593			qtd->complete_split = 0;
1594		dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_XACT_ERR);
1595		break;
1596	case USB_ENDPOINT_XFER_ISOC:
1597		{
1598			enum dwc2_halt_status halt_status;
1599
1600			halt_status = dwc2_update_isoc_urb_state(hsotg, chan,
1601					chnum, qtd, DWC2_HC_XFER_XACT_ERR);
1602			dwc2_halt_channel(hsotg, chan, qtd, halt_status);
1603		}
1604		break;
1605	}
1606
1607handle_xacterr_done:
1608	disable_hc_int(hsotg, chnum, HCINTMSK_XACTERR);
1609}
1610
1611/*
1612 * Handles a host channel frame overrun interrupt. This handler may be called
1613 * in either DMA mode or Slave mode.
1614 */
1615static void dwc2_hc_frmovrun_intr(struct dwc2_hsotg *hsotg,
1616				  struct dwc2_host_chan *chan, int chnum,
1617				  struct dwc2_qtd *qtd)
1618{
1619	enum dwc2_halt_status halt_status;
1620
1621	if (dbg_hc(chan))
1622		dev_dbg(hsotg->dev, "--Host Channel %d Interrupt: Frame Overrun--\n",
1623			chnum);
1624
1625	dwc2_hc_handle_tt_clear(hsotg, chan, qtd);
1626
1627	switch (dwc2_hcd_get_pipe_type(&qtd->urb->pipe_info)) {
1628	case USB_ENDPOINT_XFER_CONTROL:
1629	case USB_ENDPOINT_XFER_BULK:
1630		break;
1631	case USB_ENDPOINT_XFER_INT:
1632		dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_FRAME_OVERRUN);
1633		break;
1634	case USB_ENDPOINT_XFER_ISOC:
1635		halt_status = dwc2_update_isoc_urb_state(hsotg, chan, chnum,
1636					qtd, DWC2_HC_XFER_FRAME_OVERRUN);
1637		dwc2_halt_channel(hsotg, chan, qtd, halt_status);
1638		break;
1639	}
1640
1641	disable_hc_int(hsotg, chnum, HCINTMSK_FRMOVRUN);
1642}
1643
1644/*
1645 * Handles a host channel data toggle error interrupt. This handler may be
1646 * called in either DMA mode or Slave mode.
1647 */
1648static void dwc2_hc_datatglerr_intr(struct dwc2_hsotg *hsotg,
1649				    struct dwc2_host_chan *chan, int chnum,
1650				    struct dwc2_qtd *qtd)
1651{
1652	dev_dbg(hsotg->dev,
1653		"--Host Channel %d Interrupt: Data Toggle Error--\n", chnum);
1654
1655	if (chan->ep_is_in)
1656		qtd->error_count = 0;
1657	else
1658		dev_err(hsotg->dev,
1659			"Data Toggle Error on OUT transfer, channel %d\n",
1660			chnum);
1661
1662	dwc2_hc_handle_tt_clear(hsotg, chan, qtd);
1663	disable_hc_int(hsotg, chnum, HCINTMSK_DATATGLERR);
1664}
1665
1666/*
1667 * For debug only. It checks that a valid halt status is set and that
1668 * HCCHARn.chdis is clear. If there's a problem, corrective action is
1669 * taken and a warning is issued.
1670 *
1671 * Return: true if halt status is ok, false otherwise
1672 */
1673static bool dwc2_halt_status_ok(struct dwc2_hsotg *hsotg,
1674				struct dwc2_host_chan *chan, int chnum,
1675				struct dwc2_qtd *qtd)
1676{
1677#ifdef DEBUG
1678	u32 hcchar;
1679	u32 hctsiz;
1680	u32 hcintmsk;
1681	u32 hcsplt;
1682
1683	if (chan->halt_status == DWC2_HC_XFER_NO_HALT_STATUS) {
1684		/*
1685		 * This code is here only as a check. This condition should
1686		 * never happen. Ignore the halt if it does occur.
1687		 */
1688		hcchar = readl(hsotg->regs + HCCHAR(chnum));
1689		hctsiz = readl(hsotg->regs + HCTSIZ(chnum));
1690		hcintmsk = readl(hsotg->regs + HCINTMSK(chnum));
1691		hcsplt = readl(hsotg->regs + HCSPLT(chnum));
1692		dev_dbg(hsotg->dev,
1693			"%s: chan->halt_status DWC2_HC_XFER_NO_HALT_STATUS,\n",
1694			 __func__);
1695		dev_dbg(hsotg->dev,
1696			"channel %d, hcchar 0x%08x, hctsiz 0x%08x,\n",
1697			chnum, hcchar, hctsiz);
1698		dev_dbg(hsotg->dev,
1699			"hcint 0x%08x, hcintmsk 0x%08x, hcsplt 0x%08x,\n",
1700			chan->hcint, hcintmsk, hcsplt);
1701		if (qtd)
1702			dev_dbg(hsotg->dev, "qtd->complete_split %d\n",
1703				qtd->complete_split);
1704		dev_warn(hsotg->dev,
1705			 "%s: no halt status, channel %d, ignoring interrupt\n",
1706			 __func__, chnum);
1707		return false;
1708	}
1709
1710	/*
1711	 * This code is here only as a check. hcchar.chdis should never be set
1712	 * when the halt interrupt occurs. Halt the channel again if it does
1713	 * occur.
1714	 */
1715	hcchar = readl(hsotg->regs + HCCHAR(chnum));
1716	if (hcchar & HCCHAR_CHDIS) {
1717		dev_warn(hsotg->dev,
1718			 "%s: hcchar.chdis set unexpectedly, hcchar 0x%08x, trying to halt again\n",
1719			 __func__, hcchar);
1720		chan->halt_pending = 0;
1721		dwc2_halt_channel(hsotg, chan, qtd, chan->halt_status);
1722		return false;
1723	}
1724#endif
1725
1726	return true;
1727}
1728
1729/*
1730 * Handles a host Channel Halted interrupt in DMA mode. This handler
1731 * determines the reason the channel halted and proceeds accordingly.
1732 */
1733static void dwc2_hc_chhltd_intr_dma(struct dwc2_hsotg *hsotg,
1734				    struct dwc2_host_chan *chan, int chnum,
1735				    struct dwc2_qtd *qtd)
1736{
1737	u32 hcintmsk;
1738	int out_nak_enh = 0;
1739
1740	if (dbg_hc(chan))
1741		dev_vdbg(hsotg->dev,
1742			 "--Host Channel %d Interrupt: DMA Channel Halted--\n",
1743			 chnum);
1744
1745	/*
1746	 * For core with OUT NAK enhancement, the flow for high-speed
1747	 * CONTROL/BULK OUT is handled a little differently
1748	 */
1749	if (hsotg->hw_params.snpsid >= DWC2_CORE_REV_2_71a) {
1750		if (chan->speed == USB_SPEED_HIGH && !chan->ep_is_in &&
1751		    (chan->ep_type == USB_ENDPOINT_XFER_CONTROL ||
1752		     chan->ep_type == USB_ENDPOINT_XFER_BULK)) {
1753			out_nak_enh = 1;
1754		}
1755	}
1756
1757	if (chan->halt_status == DWC2_HC_XFER_URB_DEQUEUE ||
1758	    (chan->halt_status == DWC2_HC_XFER_AHB_ERR &&
1759	     hsotg->core_params->dma_desc_enable <= 0)) {
1760		if (hsotg->core_params->dma_desc_enable > 0)
1761			dwc2_hcd_complete_xfer_ddma(hsotg, chan, chnum,
1762						    chan->halt_status);
1763		else
1764			/*
1765			 * Just release the channel. A dequeue can happen on a
1766			 * transfer timeout. In the case of an AHB Error, the
1767			 * channel was forced to halt because there's no way to
1768			 * gracefully recover.
1769			 */
1770			dwc2_release_channel(hsotg, chan, qtd,
1771					     chan->halt_status);
1772		return;
1773	}
1774
1775	hcintmsk = readl(hsotg->regs + HCINTMSK(chnum));
1776
1777	if (chan->hcint & HCINTMSK_XFERCOMPL) {
1778		/*
1779		 * Todo: This is here because of a possible hardware bug. Spec
1780		 * says that on SPLIT-ISOC OUT transfers in DMA mode that a HALT
1781		 * interrupt w/ACK bit set should occur, but I only see the
1782		 * XFERCOMP bit, even with it masked out. This is a workaround
1783		 * for that behavior. Should fix this when hardware is fixed.
1784		 */
1785		if (chan->ep_type == USB_ENDPOINT_XFER_ISOC && !chan->ep_is_in)
1786			dwc2_hc_ack_intr(hsotg, chan, chnum, qtd);
1787		dwc2_hc_xfercomp_intr(hsotg, chan, chnum, qtd);
1788	} else if (chan->hcint & HCINTMSK_STALL) {
1789		dwc2_hc_stall_intr(hsotg, chan, chnum, qtd);
1790	} else if ((chan->hcint & HCINTMSK_XACTERR) &&
1791		   hsotg->core_params->dma_desc_enable <= 0) {
1792		if (out_nak_enh) {
1793			if (chan->hcint &
1794			    (HCINTMSK_NYET | HCINTMSK_NAK | HCINTMSK_ACK)) {
1795				dev_vdbg(hsotg->dev,
1796					 "XactErr with NYET/NAK/ACK\n");
1797				qtd->error_count = 0;
1798			} else {
1799				dev_vdbg(hsotg->dev,
1800					 "XactErr without NYET/NAK/ACK\n");
1801			}
1802		}
1803
1804		/*
1805		 * Must handle xacterr before nak or ack. Could get a xacterr
1806		 * at the same time as either of these on a BULK/CONTROL OUT
1807		 * that started with a PING. The xacterr takes precedence.
1808		 */
1809		dwc2_hc_xacterr_intr(hsotg, chan, chnum, qtd);
1810	} else if ((chan->hcint & HCINTMSK_XCS_XACT) &&
1811		   hsotg->core_params->dma_desc_enable > 0) {
1812		dwc2_hc_xacterr_intr(hsotg, chan, chnum, qtd);
1813	} else if ((chan->hcint & HCINTMSK_AHBERR) &&
1814		   hsotg->core_params->dma_desc_enable > 0) {
1815		dwc2_hc_ahberr_intr(hsotg, chan, chnum, qtd);
1816	} else if (chan->hcint & HCINTMSK_BBLERR) {
1817		dwc2_hc_babble_intr(hsotg, chan, chnum, qtd);
1818	} else if (chan->hcint & HCINTMSK_FRMOVRUN) {
1819		dwc2_hc_frmovrun_intr(hsotg, chan, chnum, qtd);
1820	} else if (!out_nak_enh) {
1821		if (chan->hcint & HCINTMSK_NYET) {
1822			/*
1823			 * Must handle nyet before nak or ack. Could get a nyet
1824			 * at the same time as either of those on a BULK/CONTROL
1825			 * OUT that started with a PING. The nyet takes
1826			 * precedence.
1827			 */
1828			dwc2_hc_nyet_intr(hsotg, chan, chnum, qtd);
1829		} else if ((chan->hcint & HCINTMSK_NAK) &&
1830			   !(hcintmsk & HCINTMSK_NAK)) {
1831			/*
1832			 * If nak is not masked, it's because a non-split IN
1833			 * transfer is in an error state. In that case, the nak
1834			 * is handled by the nak interrupt handler, not here.
1835			 * Handle nak here for BULK/CONTROL OUT transfers, which
1836			 * halt on a NAK to allow rewinding the buffer pointer.
1837			 */
1838			dwc2_hc_nak_intr(hsotg, chan, chnum, qtd);
1839		} else if ((chan->hcint & HCINTMSK_ACK) &&
1840			   !(hcintmsk & HCINTMSK_ACK)) {
1841			/*
1842			 * If ack is not masked, it's because a non-split IN
1843			 * transfer is in an error state. In that case, the ack
1844			 * is handled by the ack interrupt handler, not here.
1845			 * Handle ack here for split transfers. Start splits
1846			 * halt on ACK.
1847			 */
1848			dwc2_hc_ack_intr(hsotg, chan, chnum, qtd);
1849		} else {
1850			if (chan->ep_type == USB_ENDPOINT_XFER_INT ||
1851			    chan->ep_type == USB_ENDPOINT_XFER_ISOC) {
1852				/*
1853				 * A periodic transfer halted with no other
1854				 * channel interrupts set. Assume it was halted
1855				 * by the core because it could not be completed
1856				 * in its scheduled (micro)frame.
1857				 */
1858				dev_dbg(hsotg->dev,
1859					"%s: Halt channel %d (assume incomplete periodic transfer)\n",
1860					__func__, chnum);
1861				dwc2_halt_channel(hsotg, chan, qtd,
1862					DWC2_HC_XFER_PERIODIC_INCOMPLETE);
1863			} else {
1864				dev_err(hsotg->dev,
1865					"%s: Channel %d - ChHltd set, but reason is unknown\n",
1866					__func__, chnum);
1867				dev_err(hsotg->dev,
1868					"hcint 0x%08x, intsts 0x%08x\n",
1869					chan->hcint,
1870					readl(hsotg->regs + GINTSTS));
1871				goto error;
1872			}
1873		}
1874	} else {
1875		dev_info(hsotg->dev,
1876			 "NYET/NAK/ACK/other in non-error case, 0x%08x\n",
1877			 chan->hcint);
1878error:
1879		/* Failthrough: use 3-strikes rule */
1880		qtd->error_count++;
1881		dwc2_update_urb_state_abn(hsotg, chan, chnum, qtd->urb,
1882					  qtd, DWC2_HC_XFER_XACT_ERR);
1883		dwc2_hcd_save_data_toggle(hsotg, chan, chnum, qtd);
1884		dwc2_halt_channel(hsotg, chan, qtd, DWC2_HC_XFER_XACT_ERR);
1885	}
1886}
1887
1888/*
1889 * Handles a host channel Channel Halted interrupt
1890 *
1891 * In slave mode, this handler is called only when the driver specifically
1892 * requests a halt. This occurs during handling other host channel interrupts
1893 * (e.g. nak, xacterr, stall, nyet, etc.).
1894 *
1895 * In DMA mode, this is the interrupt that occurs when the core has finished
1896 * processing a transfer on a channel. Other host channel interrupts (except
1897 * ahberr) are disabled in DMA mode.
1898 */
1899static void dwc2_hc_chhltd_intr(struct dwc2_hsotg *hsotg,
1900				struct dwc2_host_chan *chan, int chnum,
1901				struct dwc2_qtd *qtd)
1902{
1903	if (dbg_hc(chan))
1904		dev_vdbg(hsotg->dev, "--Host Channel %d Interrupt: Channel Halted--\n",
1905			 chnum);
1906
1907	if (hsotg->core_params->dma_enable > 0) {
1908		dwc2_hc_chhltd_intr_dma(hsotg, chan, chnum, qtd);
1909	} else {
1910		if (!dwc2_halt_status_ok(hsotg, chan, chnum, qtd))
1911			return;
1912		dwc2_release_channel(hsotg, chan, qtd, chan->halt_status);
1913	}
1914}
1915
1916/* Handles interrupt for a specific Host Channel */
1917static void dwc2_hc_n_intr(struct dwc2_hsotg *hsotg, int chnum)
1918{
1919	struct dwc2_qtd *qtd;
1920	struct dwc2_host_chan *chan;
1921	u32 hcint, hcintmsk;
1922
1923	chan = hsotg->hc_ptr_array[chnum];
1924
1925	hcint = readl(hsotg->regs + HCINT(chnum));
1926	hcintmsk = readl(hsotg->regs + HCINTMSK(chnum));
1927	if (!chan) {
1928		dev_err(hsotg->dev, "## hc_ptr_array for channel is NULL ##\n");
1929		writel(hcint, hsotg->regs + HCINT(chnum));
1930		return;
1931	}
1932
1933	if (dbg_hc(chan)) {
1934		dev_vdbg(hsotg->dev, "--Host Channel Interrupt--, Channel %d\n",
1935			 chnum);
1936		dev_vdbg(hsotg->dev,
1937			 "  hcint 0x%08x, hcintmsk 0x%08x, hcint&hcintmsk 0x%08x\n",
1938			 hcint, hcintmsk, hcint & hcintmsk);
1939	}
1940
1941	writel(hcint, hsotg->regs + HCINT(chnum));
1942	chan->hcint = hcint;
1943	hcint &= hcintmsk;
1944
1945	/*
1946	 * If the channel was halted due to a dequeue, the qtd list might
1947	 * be empty or at least the first entry will not be the active qtd.
1948	 * In this case, take a shortcut and just release the channel.
1949	 */
1950	if (chan->halt_status == DWC2_HC_XFER_URB_DEQUEUE) {
1951		/*
1952		 * If the channel was halted, this should be the only
1953		 * interrupt unmasked
1954		 */
1955		WARN_ON(hcint != HCINTMSK_CHHLTD);
1956		if (hsotg->core_params->dma_desc_enable > 0)
1957			dwc2_hcd_complete_xfer_ddma(hsotg, chan, chnum,
1958						    chan->halt_status);
1959		else
1960			dwc2_release_channel(hsotg, chan, NULL,
1961					     chan->halt_status);
1962		return;
1963	}
1964
1965	if (list_empty(&chan->qh->qtd_list)) {
1966		/*
1967		 * TODO: Will this ever happen with the
1968		 * DWC2_HC_XFER_URB_DEQUEUE handling above?
1969		 */
1970		dev_dbg(hsotg->dev, "## no QTD queued for channel %d ##\n",
1971			chnum);
1972		dev_dbg(hsotg->dev,
1973			"  hcint 0x%08x, hcintmsk 0x%08x, hcint&hcintmsk 0x%08x\n",
1974			chan->hcint, hcintmsk, hcint);
1975		chan->halt_status = DWC2_HC_XFER_NO_HALT_STATUS;
1976		disable_hc_int(hsotg, chnum, HCINTMSK_CHHLTD);
1977		chan->hcint = 0;
1978		return;
1979	}
1980
1981	qtd = list_first_entry(&chan->qh->qtd_list, struct dwc2_qtd,
1982			       qtd_list_entry);
1983
1984	if (hsotg->core_params->dma_enable <= 0) {
1985		if ((hcint & HCINTMSK_CHHLTD) && hcint != HCINTMSK_CHHLTD)
1986			hcint &= ~HCINTMSK_CHHLTD;
1987	}
1988
1989	if (hcint & HCINTMSK_XFERCOMPL) {
1990		dwc2_hc_xfercomp_intr(hsotg, chan, chnum, qtd);
1991		/*
1992		 * If NYET occurred at same time as Xfer Complete, the NYET is
1993		 * handled by the Xfer Complete interrupt handler. Don't want
1994		 * to call the NYET interrupt handler in this case.
1995		 */
1996		hcint &= ~HCINTMSK_NYET;
1997	}
1998	if (hcint & HCINTMSK_CHHLTD)
1999		dwc2_hc_chhltd_intr(hsotg, chan, chnum, qtd);
2000	if (hcint & HCINTMSK_AHBERR)
2001		dwc2_hc_ahberr_intr(hsotg, chan, chnum, qtd);
2002	if (hcint & HCINTMSK_STALL)
2003		dwc2_hc_stall_intr(hsotg, chan, chnum, qtd);
2004	if (hcint & HCINTMSK_NAK)
2005		dwc2_hc_nak_intr(hsotg, chan, chnum, qtd);
2006	if (hcint & HCINTMSK_ACK)
2007		dwc2_hc_ack_intr(hsotg, chan, chnum, qtd);
2008	if (hcint & HCINTMSK_NYET)
2009		dwc2_hc_nyet_intr(hsotg, chan, chnum, qtd);
2010	if (hcint & HCINTMSK_XACTERR)
2011		dwc2_hc_xacterr_intr(hsotg, chan, chnum, qtd);
2012	if (hcint & HCINTMSK_BBLERR)
2013		dwc2_hc_babble_intr(hsotg, chan, chnum, qtd);
2014	if (hcint & HCINTMSK_FRMOVRUN)
2015		dwc2_hc_frmovrun_intr(hsotg, chan, chnum, qtd);
2016	if (hcint & HCINTMSK_DATATGLERR)
2017		dwc2_hc_datatglerr_intr(hsotg, chan, chnum, qtd);
2018
2019	chan->hcint = 0;
2020}
2021
2022/*
2023 * This interrupt indicates that one or more host channels has a pending
2024 * interrupt. There are multiple conditions that can cause each host channel
2025 * interrupt. This function determines which conditions have occurred for each
2026 * host channel interrupt and handles them appropriately.
2027 */
2028static void dwc2_hc_intr(struct dwc2_hsotg *hsotg)
2029{
2030	u32 haint;
2031	int i;
2032
2033	haint = readl(hsotg->regs + HAINT);
2034	if (dbg_perio()) {
2035		dev_vdbg(hsotg->dev, "%s()\n", __func__);
2036
2037		dev_vdbg(hsotg->dev, "HAINT=%08x\n", haint);
2038	}
2039
2040	for (i = 0; i < hsotg->core_params->host_channels; i++) {
2041		if (haint & (1 << i))
2042			dwc2_hc_n_intr(hsotg, i);
2043	}
2044}
2045
2046/* This function handles interrupts for the HCD */
2047irqreturn_t dwc2_handle_hcd_intr(struct dwc2_hsotg *hsotg)
2048{
2049	u32 gintsts, dbg_gintsts;
2050	irqreturn_t retval = IRQ_NONE;
2051
2052	if (!dwc2_is_controller_alive(hsotg)) {
2053		dev_warn(hsotg->dev, "Controller is dead\n");
2054		return retval;
2055	}
2056
2057	spin_lock(&hsotg->lock);
2058
2059	/* Check if HOST Mode */
2060	if (dwc2_is_host_mode(hsotg)) {
2061		gintsts = dwc2_read_core_intr(hsotg);
2062		if (!gintsts) {
2063			spin_unlock(&hsotg->lock);
2064			return retval;
2065		}
2066
2067		retval = IRQ_HANDLED;
2068
2069		dbg_gintsts = gintsts;
2070#ifndef DEBUG_SOF
2071		dbg_gintsts &= ~GINTSTS_SOF;
2072#endif
2073		if (!dbg_perio())
2074			dbg_gintsts &= ~(GINTSTS_HCHINT | GINTSTS_RXFLVL |
2075					 GINTSTS_PTXFEMP);
2076
2077		/* Only print if there are any non-suppressed interrupts left */
2078		if (dbg_gintsts)
2079			dev_vdbg(hsotg->dev,
2080				 "DWC OTG HCD Interrupt Detected gintsts&gintmsk=0x%08x\n",
2081				 gintsts);
2082
2083		if (gintsts & GINTSTS_SOF)
2084			dwc2_sof_intr(hsotg);
2085		if (gintsts & GINTSTS_RXFLVL)
2086			dwc2_rx_fifo_level_intr(hsotg);
2087		if (gintsts & GINTSTS_NPTXFEMP)
2088			dwc2_np_tx_fifo_empty_intr(hsotg);
2089		if (gintsts & GINTSTS_PRTINT)
2090			dwc2_port_intr(hsotg);
2091		if (gintsts & GINTSTS_HCHINT)
2092			dwc2_hc_intr(hsotg);
2093		if (gintsts & GINTSTS_PTXFEMP)
2094			dwc2_perio_tx_fifo_empty_intr(hsotg);
2095
2096		if (dbg_gintsts) {
2097			dev_vdbg(hsotg->dev,
2098				 "DWC OTG HCD Finished Servicing Interrupts\n");
2099			dev_vdbg(hsotg->dev,
2100				 "DWC OTG HCD gintsts=0x%08x gintmsk=0x%08x\n",
2101				 readl(hsotg->regs + GINTSTS),
2102				 readl(hsotg->regs + GINTMSK));
2103		}
2104	}
2105
2106	spin_unlock(&hsotg->lock);
2107
2108	return retval;
2109}
2110