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v6.8
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * MUSB OTG driver host support
   4 *
   5 * Copyright 2005 Mentor Graphics Corporation
   6 * Copyright (C) 2005-2006 by Texas Instruments
   7 * Copyright (C) 2006-2007 Nokia Corporation
   8 * Copyright (C) 2008-2009 MontaVista Software, Inc. <source@mvista.com>
   9 */
  10
  11#include <linux/module.h>
  12#include <linux/kernel.h>
  13#include <linux/delay.h>
  14#include <linux/sched.h>
  15#include <linux/slab.h>
  16#include <linux/errno.h>
  17#include <linux/list.h>
  18#include <linux/dma-mapping.h>
  19
  20#include "musb_core.h"
  21#include "musb_host.h"
  22#include "musb_trace.h"
  23
  24/* MUSB HOST status 22-mar-2006
  25 *
  26 * - There's still lots of partial code duplication for fault paths, so
  27 *   they aren't handled as consistently as they need to be.
  28 *
  29 * - PIO mostly behaved when last tested.
  30 *     + including ep0, with all usbtest cases 9, 10
  31 *     + usbtest 14 (ep0out) doesn't seem to run at all
  32 *     + double buffered OUT/TX endpoints saw stalls(!) with certain usbtest
  33 *       configurations, but otherwise double buffering passes basic tests.
  34 *     + for 2.6.N, for N > ~10, needs API changes for hcd framework.
  35 *
  36 * - DMA (CPPI) ... partially behaves, not currently recommended
  37 *     + about 1/15 the speed of typical EHCI implementations (PCI)
  38 *     + RX, all too often reqpkt seems to misbehave after tx
  39 *     + TX, no known issues (other than evident silicon issue)
  40 *
  41 * - DMA (Mentor/OMAP) ...has at least toggle update problems
  42 *
  43 * - [23-feb-2009] minimal traffic scheduling to avoid bulk RX packet
  44 *   starvation ... nothing yet for TX, interrupt, or bulk.
  45 *
  46 * - Not tested with HNP, but some SRP paths seem to behave.
  47 *
  48 * NOTE 24-August-2006:
  49 *
  50 * - Bulk traffic finally uses both sides of hardware ep1, freeing up an
  51 *   extra endpoint for periodic use enabling hub + keybd + mouse.  That
  52 *   mostly works, except that with "usbnet" it's easy to trigger cases
  53 *   with "ping" where RX loses.  (a) ping to davinci, even "ping -f",
  54 *   fine; but (b) ping _from_ davinci, even "ping -c 1", ICMP RX loses
  55 *   although ARP RX wins.  (That test was done with a full speed link.)
  56 */
  57
  58
  59/*
  60 * NOTE on endpoint usage:
  61 *
  62 * CONTROL transfers all go through ep0.  BULK ones go through dedicated IN
  63 * and OUT endpoints ... hardware is dedicated for those "async" queue(s).
  64 * (Yes, bulk _could_ use more of the endpoints than that, and would even
  65 * benefit from it.)
  66 *
  67 * INTERUPPT and ISOCHRONOUS transfers are scheduled to the other endpoints.
  68 * So far that scheduling is both dumb and optimistic:  the endpoint will be
  69 * "claimed" until its software queue is no longer refilled.  No multiplexing
  70 * of transfers between endpoints, or anything clever.
  71 */
  72
  73struct musb *hcd_to_musb(struct usb_hcd *hcd)
  74{
  75	return *(struct musb **) hcd->hcd_priv;
  76}
  77
  78
  79static void musb_ep_program(struct musb *musb, u8 epnum,
  80			struct urb *urb, int is_out,
  81			u8 *buf, u32 offset, u32 len);
  82
  83/*
  84 * Clear TX fifo. Needed to avoid BABBLE errors.
  85 */
  86static void musb_h_tx_flush_fifo(struct musb_hw_ep *ep)
  87{
  88	struct musb	*musb = ep->musb;
  89	void __iomem	*epio = ep->regs;
  90	u16		csr;
  91	int		retries = 1000;
  92
  93	csr = musb_readw(epio, MUSB_TXCSR);
  94	while (csr & MUSB_TXCSR_FIFONOTEMPTY) {
  95		csr |= MUSB_TXCSR_FLUSHFIFO | MUSB_TXCSR_TXPKTRDY;
  96		musb_writew(epio, MUSB_TXCSR, csr);
  97		csr = musb_readw(epio, MUSB_TXCSR);
  98
  99		/*
 100		 * FIXME: sometimes the tx fifo flush failed, it has been
 101		 * observed during device disconnect on AM335x.
 102		 *
 103		 * To reproduce the issue, ensure tx urb(s) are queued when
 104		 * unplug the usb device which is connected to AM335x usb
 105		 * host port.
 106		 *
 107		 * I found using a usb-ethernet device and running iperf
 108		 * (client on AM335x) has very high chance to trigger it.
 109		 *
 110		 * Better to turn on musb_dbg() in musb_cleanup_urb() with
 111		 * CPPI enabled to see the issue when aborting the tx channel.
 112		 */
 113		if (dev_WARN_ONCE(musb->controller, retries-- < 1,
 114				"Could not flush host TX%d fifo: csr: %04x\n",
 115				ep->epnum, csr))
 116			return;
 117		mdelay(1);
 118	}
 119}
 120
 121static void musb_h_ep0_flush_fifo(struct musb_hw_ep *ep)
 122{
 123	void __iomem	*epio = ep->regs;
 124	u16		csr;
 125	int		retries = 5;
 126
 127	/* scrub any data left in the fifo */
 128	do {
 129		csr = musb_readw(epio, MUSB_TXCSR);
 130		if (!(csr & (MUSB_CSR0_TXPKTRDY | MUSB_CSR0_RXPKTRDY)))
 131			break;
 132		musb_writew(epio, MUSB_TXCSR, MUSB_CSR0_FLUSHFIFO);
 133		csr = musb_readw(epio, MUSB_TXCSR);
 134		udelay(10);
 135	} while (--retries);
 136
 137	WARN(!retries, "Could not flush host TX%d fifo: csr: %04x\n",
 138			ep->epnum, csr);
 139
 140	/* and reset for the next transfer */
 141	musb_writew(epio, MUSB_TXCSR, 0);
 142}
 143
 144/*
 145 * Start transmit. Caller is responsible for locking shared resources.
 146 * musb must be locked.
 147 */
 148static inline void musb_h_tx_start(struct musb_hw_ep *ep)
 149{
 150	u16	txcsr;
 151
 152	/* NOTE: no locks here; caller should lock and select EP */
 153	if (ep->epnum) {
 154		txcsr = musb_readw(ep->regs, MUSB_TXCSR);
 155		txcsr |= MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_H_WZC_BITS;
 156		musb_writew(ep->regs, MUSB_TXCSR, txcsr);
 157	} else {
 158		txcsr = MUSB_CSR0_H_SETUPPKT | MUSB_CSR0_TXPKTRDY;
 159		musb_writew(ep->regs, MUSB_CSR0, txcsr);
 160	}
 161
 162}
 163
 164static inline void musb_h_tx_dma_start(struct musb_hw_ep *ep)
 165{
 166	u16	txcsr;
 167
 168	/* NOTE: no locks here; caller should lock and select EP */
 169	txcsr = musb_readw(ep->regs, MUSB_TXCSR);
 170	txcsr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_H_WZC_BITS;
 171	if (is_cppi_enabled(ep->musb))
 172		txcsr |= MUSB_TXCSR_DMAMODE;
 173	musb_writew(ep->regs, MUSB_TXCSR, txcsr);
 174}
 175
 176static void musb_ep_set_qh(struct musb_hw_ep *ep, int is_in, struct musb_qh *qh)
 177{
 178	if (is_in != 0 || ep->is_shared_fifo)
 179		ep->in_qh  = qh;
 180	if (is_in == 0 || ep->is_shared_fifo)
 181		ep->out_qh = qh;
 182}
 183
 184static struct musb_qh *musb_ep_get_qh(struct musb_hw_ep *ep, int is_in)
 185{
 186	return is_in ? ep->in_qh : ep->out_qh;
 187}
 188
 189/*
 190 * Start the URB at the front of an endpoint's queue
 191 * end must be claimed from the caller.
 192 *
 193 * Context: controller locked, irqs blocked
 194 */
 195static void
 196musb_start_urb(struct musb *musb, int is_in, struct musb_qh *qh)
 197{
 198	u32			len;
 199	void __iomem		*mbase =  musb->mregs;
 200	struct urb		*urb = next_urb(qh);
 201	void			*buf = urb->transfer_buffer;
 202	u32			offset = 0;
 203	struct musb_hw_ep	*hw_ep = qh->hw_ep;
 204	int			epnum = hw_ep->epnum;
 205
 206	/* initialize software qh state */
 207	qh->offset = 0;
 208	qh->segsize = 0;
 209
 210	/* gather right source of data */
 211	switch (qh->type) {
 212	case USB_ENDPOINT_XFER_CONTROL:
 213		/* control transfers always start with SETUP */
 214		is_in = 0;
 215		musb->ep0_stage = MUSB_EP0_START;
 216		buf = urb->setup_packet;
 217		len = 8;
 218		break;
 219	case USB_ENDPOINT_XFER_ISOC:
 220		qh->iso_idx = 0;
 221		qh->frame = 0;
 222		offset = urb->iso_frame_desc[0].offset;
 223		len = urb->iso_frame_desc[0].length;
 224		break;
 225	default:		/* bulk, interrupt */
 226		/* actual_length may be nonzero on retry paths */
 227		buf = urb->transfer_buffer + urb->actual_length;
 228		len = urb->transfer_buffer_length - urb->actual_length;
 229	}
 230
 231	trace_musb_urb_start(musb, urb);
 232
 233	/* Configure endpoint */
 234	musb_ep_set_qh(hw_ep, is_in, qh);
 235	musb_ep_program(musb, epnum, urb, !is_in, buf, offset, len);
 236
 237	/* transmit may have more work: start it when it is time */
 238	if (is_in)
 239		return;
 240
 241	/* determine if the time is right for a periodic transfer */
 242	switch (qh->type) {
 243	case USB_ENDPOINT_XFER_ISOC:
 244	case USB_ENDPOINT_XFER_INT:
 245		musb_dbg(musb, "check whether there's still time for periodic Tx");
 246		/* FIXME this doesn't implement that scheduling policy ...
 247		 * or handle framecounter wrapping
 248		 */
 249		if (1) {	/* Always assume URB_ISO_ASAP */
 250			/* REVISIT the SOF irq handler shouldn't duplicate
 251			 * this code; and we don't init urb->start_frame...
 252			 */
 253			qh->frame = 0;
 254			goto start;
 255		} else {
 256			qh->frame = urb->start_frame;
 257			/* enable SOF interrupt so we can count down */
 258			musb_dbg(musb, "SOF for %d", epnum);
 259#if 1 /* ifndef	CONFIG_ARCH_DAVINCI */
 260			musb_writeb(mbase, MUSB_INTRUSBE, 0xff);
 261#endif
 262		}
 263		break;
 264	default:
 265start:
 266		musb_dbg(musb, "Start TX%d %s", epnum,
 267			hw_ep->tx_channel ? "dma" : "pio");
 268
 269		if (!hw_ep->tx_channel)
 270			musb_h_tx_start(hw_ep);
 271		else if (is_cppi_enabled(musb) || tusb_dma_omap(musb))
 272			musb_h_tx_dma_start(hw_ep);
 273	}
 274}
 275
 276/* Context: caller owns controller lock, IRQs are blocked */
 277static void musb_giveback(struct musb *musb, struct urb *urb, int status)
 278__releases(musb->lock)
 279__acquires(musb->lock)
 280{
 281	trace_musb_urb_gb(musb, urb);
 282
 283	usb_hcd_unlink_urb_from_ep(musb->hcd, urb);
 284	spin_unlock(&musb->lock);
 285	usb_hcd_giveback_urb(musb->hcd, urb, status);
 286	spin_lock(&musb->lock);
 287}
 288
 289/*
 290 * Advance this hardware endpoint's queue, completing the specified URB and
 291 * advancing to either the next URB queued to that qh, or else invalidating
 292 * that qh and advancing to the next qh scheduled after the current one.
 293 *
 294 * Context: caller owns controller lock, IRQs are blocked
 295 */
 296static void musb_advance_schedule(struct musb *musb, struct urb *urb,
 297				  struct musb_hw_ep *hw_ep, int is_in)
 298{
 299	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, is_in);
 300	struct musb_hw_ep	*ep = qh->hw_ep;
 301	int			ready = qh->is_ready;
 302	int			status;
 303	u16			toggle;
 304
 305	status = (urb->status == -EINPROGRESS) ? 0 : urb->status;
 306
 307	/* save toggle eagerly, for paranoia */
 308	switch (qh->type) {
 309	case USB_ENDPOINT_XFER_BULK:
 310	case USB_ENDPOINT_XFER_INT:
 311		toggle = musb->io.get_toggle(qh, !is_in);
 312		usb_settoggle(urb->dev, qh->epnum, !is_in, toggle ? 1 : 0);
 313		break;
 314	case USB_ENDPOINT_XFER_ISOC:
 315		if (status == 0 && urb->error_count)
 316			status = -EXDEV;
 317		break;
 318	}
 319
 320	qh->is_ready = 0;
 321	musb_giveback(musb, urb, status);
 322	qh->is_ready = ready;
 323
 324	/*
 325	 * musb->lock had been unlocked in musb_giveback, so qh may
 326	 * be freed, need to get it again
 327	 */
 328	qh = musb_ep_get_qh(hw_ep, is_in);
 329
 330	/* reclaim resources (and bandwidth) ASAP; deschedule it, and
 331	 * invalidate qh as soon as list_empty(&hep->urb_list)
 332	 */
 333	if (qh && list_empty(&qh->hep->urb_list)) {
 334		struct list_head	*head;
 335		struct dma_controller	*dma = musb->dma_controller;
 336
 337		if (is_in) {
 338			ep->rx_reinit = 1;
 339			if (ep->rx_channel) {
 340				dma->channel_release(ep->rx_channel);
 341				ep->rx_channel = NULL;
 342			}
 343		} else {
 344			ep->tx_reinit = 1;
 345			if (ep->tx_channel) {
 346				dma->channel_release(ep->tx_channel);
 347				ep->tx_channel = NULL;
 348			}
 349		}
 350
 351		/* Clobber old pointers to this qh */
 352		musb_ep_set_qh(ep, is_in, NULL);
 353		qh->hep->hcpriv = NULL;
 354
 355		switch (qh->type) {
 356
 357		case USB_ENDPOINT_XFER_CONTROL:
 358		case USB_ENDPOINT_XFER_BULK:
 359			/* fifo policy for these lists, except that NAKing
 360			 * should rotate a qh to the end (for fairness).
 361			 */
 362			if (qh->mux == 1) {
 363				head = qh->ring.prev;
 364				list_del(&qh->ring);
 365				kfree(qh);
 366				qh = first_qh(head);
 367				break;
 368			}
 369			fallthrough;
 370
 371		case USB_ENDPOINT_XFER_ISOC:
 372		case USB_ENDPOINT_XFER_INT:
 373			/* this is where periodic bandwidth should be
 374			 * de-allocated if it's tracked and allocated;
 375			 * and where we'd update the schedule tree...
 376			 */
 377			kfree(qh);
 378			qh = NULL;
 379			break;
 380		}
 381	}
 382
 383	if (qh != NULL && qh->is_ready) {
 384		musb_dbg(musb, "... next ep%d %cX urb %p",
 385		    hw_ep->epnum, is_in ? 'R' : 'T', next_urb(qh));
 386		musb_start_urb(musb, is_in, qh);
 387	}
 388}
 389
 390static u16 musb_h_flush_rxfifo(struct musb_hw_ep *hw_ep, u16 csr)
 391{
 392	/* we don't want fifo to fill itself again;
 393	 * ignore dma (various models),
 394	 * leave toggle alone (may not have been saved yet)
 395	 */
 396	csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_RXPKTRDY;
 397	csr &= ~(MUSB_RXCSR_H_REQPKT
 398		| MUSB_RXCSR_H_AUTOREQ
 399		| MUSB_RXCSR_AUTOCLEAR);
 400
 401	/* write 2x to allow double buffering */
 402	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
 403	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
 404
 405	/* flush writebuffer */
 406	return musb_readw(hw_ep->regs, MUSB_RXCSR);
 407}
 408
 409/*
 410 * PIO RX for a packet (or part of it).
 411 */
 412static bool
 413musb_host_packet_rx(struct musb *musb, struct urb *urb, u8 epnum, u8 iso_err)
 414{
 415	u16			rx_count;
 416	u8			*buf;
 417	u16			csr;
 418	bool			done = false;
 419	u32			length;
 420	int			do_flush = 0;
 421	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
 422	void __iomem		*epio = hw_ep->regs;
 423	struct musb_qh		*qh = hw_ep->in_qh;
 424	int			pipe = urb->pipe;
 425	void			*buffer = urb->transfer_buffer;
 426
 427	/* musb_ep_select(mbase, epnum); */
 428	rx_count = musb_readw(epio, MUSB_RXCOUNT);
 429	musb_dbg(musb, "RX%d count %d, buffer %p len %d/%d", epnum, rx_count,
 430			urb->transfer_buffer, qh->offset,
 431			urb->transfer_buffer_length);
 432
 433	/* unload FIFO */
 434	if (usb_pipeisoc(pipe)) {
 435		int					status = 0;
 436		struct usb_iso_packet_descriptor	*d;
 437
 438		if (iso_err) {
 439			status = -EILSEQ;
 440			urb->error_count++;
 441		}
 442
 443		d = urb->iso_frame_desc + qh->iso_idx;
 444		buf = buffer + d->offset;
 445		length = d->length;
 446		if (rx_count > length) {
 447			if (status == 0) {
 448				status = -EOVERFLOW;
 449				urb->error_count++;
 450			}
 451			musb_dbg(musb, "OVERFLOW %d into %d", rx_count, length);
 452			do_flush = 1;
 453		} else
 454			length = rx_count;
 455		urb->actual_length += length;
 456		d->actual_length = length;
 457
 458		d->status = status;
 459
 460		/* see if we are done */
 461		done = (++qh->iso_idx >= urb->number_of_packets);
 462	} else {
 463		/* non-isoch */
 464		buf = buffer + qh->offset;
 465		length = urb->transfer_buffer_length - qh->offset;
 466		if (rx_count > length) {
 467			if (urb->status == -EINPROGRESS)
 468				urb->status = -EOVERFLOW;
 469			musb_dbg(musb, "OVERFLOW %d into %d", rx_count, length);
 470			do_flush = 1;
 471		} else
 472			length = rx_count;
 473		urb->actual_length += length;
 474		qh->offset += length;
 475
 476		/* see if we are done */
 477		done = (urb->actual_length == urb->transfer_buffer_length)
 478			|| (rx_count < qh->maxpacket)
 479			|| (urb->status != -EINPROGRESS);
 480		if (done
 481				&& (urb->status == -EINPROGRESS)
 482				&& (urb->transfer_flags & URB_SHORT_NOT_OK)
 483				&& (urb->actual_length
 484					< urb->transfer_buffer_length))
 485			urb->status = -EREMOTEIO;
 486	}
 487
 488	musb_read_fifo(hw_ep, length, buf);
 489
 490	csr = musb_readw(epio, MUSB_RXCSR);
 491	csr |= MUSB_RXCSR_H_WZC_BITS;
 492	if (unlikely(do_flush))
 493		musb_h_flush_rxfifo(hw_ep, csr);
 494	else {
 495		/* REVISIT this assumes AUTOCLEAR is never set */
 496		csr &= ~(MUSB_RXCSR_RXPKTRDY | MUSB_RXCSR_H_REQPKT);
 497		if (!done)
 498			csr |= MUSB_RXCSR_H_REQPKT;
 499		musb_writew(epio, MUSB_RXCSR, csr);
 500	}
 501
 502	return done;
 503}
 504
 505/* we don't always need to reinit a given side of an endpoint...
 506 * when we do, use tx/rx reinit routine and then construct a new CSR
 507 * to address data toggle, NYET, and DMA or PIO.
 508 *
 509 * it's possible that driver bugs (especially for DMA) or aborting a
 510 * transfer might have left the endpoint busier than it should be.
 511 * the busy/not-empty tests are basically paranoia.
 512 */
 513static void
 514musb_rx_reinit(struct musb *musb, struct musb_qh *qh, u8 epnum)
 515{
 516	struct musb_hw_ep *ep = musb->endpoints + epnum;
 517	u16	csr;
 518
 519	/* NOTE:  we know the "rx" fifo reinit never triggers for ep0.
 520	 * That always uses tx_reinit since ep0 repurposes TX register
 521	 * offsets; the initial SETUP packet is also a kind of OUT.
 522	 */
 523
 524	/* if programmed for Tx, put it in RX mode */
 525	if (ep->is_shared_fifo) {
 526		csr = musb_readw(ep->regs, MUSB_TXCSR);
 527		if (csr & MUSB_TXCSR_MODE) {
 528			musb_h_tx_flush_fifo(ep);
 529			csr = musb_readw(ep->regs, MUSB_TXCSR);
 530			musb_writew(ep->regs, MUSB_TXCSR,
 531				    csr | MUSB_TXCSR_FRCDATATOG);
 532		}
 533
 534		/*
 535		 * Clear the MODE bit (and everything else) to enable Rx.
 536		 * NOTE: we mustn't clear the DMAMODE bit before DMAENAB.
 537		 */
 538		if (csr & MUSB_TXCSR_DMAMODE)
 539			musb_writew(ep->regs, MUSB_TXCSR, MUSB_TXCSR_DMAMODE);
 540		musb_writew(ep->regs, MUSB_TXCSR, 0);
 541
 542	/* scrub all previous state, clearing toggle */
 543	}
 544	csr = musb_readw(ep->regs, MUSB_RXCSR);
 545	if (csr & MUSB_RXCSR_RXPKTRDY)
 546		WARNING("rx%d, packet/%d ready?\n", ep->epnum,
 547			musb_readw(ep->regs, MUSB_RXCOUNT));
 548
 549	musb_h_flush_rxfifo(ep, MUSB_RXCSR_CLRDATATOG);
 550
 551	/* target addr and (for multipoint) hub addr/port */
 552	if (musb->is_multipoint) {
 553		musb_write_rxfunaddr(musb, epnum, qh->addr_reg);
 554		musb_write_rxhubaddr(musb, epnum, qh->h_addr_reg);
 555		musb_write_rxhubport(musb, epnum, qh->h_port_reg);
 556	} else
 557		musb_writeb(musb->mregs, MUSB_FADDR, qh->addr_reg);
 558
 559	/* protocol/endpoint, interval/NAKlimit, i/o size */
 560	musb_writeb(ep->regs, MUSB_RXTYPE, qh->type_reg);
 561	musb_writeb(ep->regs, MUSB_RXINTERVAL, qh->intv_reg);
 562	/* NOTE: bulk combining rewrites high bits of maxpacket */
 563	/* Set RXMAXP with the FIFO size of the endpoint
 564	 * to disable double buffer mode.
 565	 */
 566	musb_writew(ep->regs, MUSB_RXMAXP,
 567			qh->maxpacket | ((qh->hb_mult - 1) << 11));
 568
 569	ep->rx_reinit = 0;
 570}
 571
 572static void musb_tx_dma_set_mode_mentor(struct musb_hw_ep *hw_ep, 
 573					struct musb_qh *qh,
 574					u32 *length, u8 *mode)
 575{
 576	struct dma_channel	*channel = hw_ep->tx_channel;
 577	void __iomem		*epio = hw_ep->regs;
 578	u16			pkt_size = qh->maxpacket;
 579	u16			csr;
 580
 581	if (*length > channel->max_len)
 582		*length = channel->max_len;
 583
 584	csr = musb_readw(epio, MUSB_TXCSR);
 585	if (*length > pkt_size) {
 586		*mode = 1;
 587		csr |= MUSB_TXCSR_DMAMODE | MUSB_TXCSR_DMAENAB;
 588		/* autoset shouldn't be set in high bandwidth */
 589		/*
 590		 * Enable Autoset according to table
 591		 * below
 592		 * bulk_split hb_mult	Autoset_Enable
 593		 *	0	1	Yes(Normal)
 594		 *	0	>1	No(High BW ISO)
 595		 *	1	1	Yes(HS bulk)
 596		 *	1	>1	Yes(FS bulk)
 597		 */
 598		if (qh->hb_mult == 1 || (qh->hb_mult > 1 &&
 599					can_bulk_split(hw_ep->musb, qh->type)))
 600			csr |= MUSB_TXCSR_AUTOSET;
 601	} else {
 602		*mode = 0;
 603		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAMODE);
 604		csr |= MUSB_TXCSR_DMAENAB; /* against programmer's guide */
 605	}
 606	channel->desired_mode = *mode;
 607	musb_writew(epio, MUSB_TXCSR, csr);
 608}
 609
 610static void musb_tx_dma_set_mode_cppi_tusb(struct musb_hw_ep *hw_ep,
 611					   struct urb *urb,
 612					   u8 *mode)
 613{
 614	struct dma_channel *channel = hw_ep->tx_channel;
 615
 616	channel->actual_len = 0;
 617
 618	/*
 619	 * TX uses "RNDIS" mode automatically but needs help
 620	 * to identify the zero-length-final-packet case.
 621	 */
 622	*mode = (urb->transfer_flags & URB_ZERO_PACKET) ? 1 : 0;
 623}
 624
 625static bool musb_tx_dma_program(struct dma_controller *dma,
 626		struct musb_hw_ep *hw_ep, struct musb_qh *qh,
 627		struct urb *urb, u32 offset, u32 length)
 628{
 629	struct dma_channel	*channel = hw_ep->tx_channel;
 630	u16			pkt_size = qh->maxpacket;
 631	u8			mode;
 632
 633	if (musb_dma_inventra(hw_ep->musb) || musb_dma_ux500(hw_ep->musb))
 634		musb_tx_dma_set_mode_mentor(hw_ep, qh,
 635					    &length, &mode);
 636	else if (is_cppi_enabled(hw_ep->musb) || tusb_dma_omap(hw_ep->musb))
 637		musb_tx_dma_set_mode_cppi_tusb(hw_ep, urb, &mode);
 638	else
 639		return false;
 640
 641	qh->segsize = length;
 642
 643	/*
 644	 * Ensure the data reaches to main memory before starting
 645	 * DMA transfer
 646	 */
 647	wmb();
 648
 649	if (!dma->channel_program(channel, pkt_size, mode,
 650			urb->transfer_dma + offset, length)) {
 651		void __iomem *epio = hw_ep->regs;
 652		u16 csr;
 653
 654		dma->channel_release(channel);
 655		hw_ep->tx_channel = NULL;
 656
 657		csr = musb_readw(epio, MUSB_TXCSR);
 658		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB);
 659		musb_writew(epio, MUSB_TXCSR, csr | MUSB_TXCSR_H_WZC_BITS);
 660		return false;
 661	}
 662	return true;
 663}
 664
 665/*
 666 * Program an HDRC endpoint as per the given URB
 667 * Context: irqs blocked, controller lock held
 668 */
 669static void musb_ep_program(struct musb *musb, u8 epnum,
 670			struct urb *urb, int is_out,
 671			u8 *buf, u32 offset, u32 len)
 672{
 673	struct dma_controller	*dma_controller;
 674	struct dma_channel	*dma_channel;
 675	u8			dma_ok;
 676	void __iomem		*mbase = musb->mregs;
 677	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
 678	void __iomem		*epio = hw_ep->regs;
 679	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, !is_out);
 680	u16			packet_sz = qh->maxpacket;
 681	u8			use_dma = 1;
 682	u16			csr;
 683
 684	musb_dbg(musb, "%s hw%d urb %p spd%d dev%d ep%d%s "
 685				"h_addr%02x h_port%02x bytes %d",
 686			is_out ? "-->" : "<--",
 687			epnum, urb, urb->dev->speed,
 688			qh->addr_reg, qh->epnum, is_out ? "out" : "in",
 689			qh->h_addr_reg, qh->h_port_reg,
 690			len);
 691
 692	musb_ep_select(mbase, epnum);
 693
 694	if (is_out && !len) {
 695		use_dma = 0;
 696		csr = musb_readw(epio, MUSB_TXCSR);
 697		csr &= ~MUSB_TXCSR_DMAENAB;
 698		musb_writew(epio, MUSB_TXCSR, csr);
 699		hw_ep->tx_channel = NULL;
 700	}
 701
 702	/* candidate for DMA? */
 703	dma_controller = musb->dma_controller;
 704	if (use_dma && is_dma_capable() && epnum && dma_controller) {
 705		dma_channel = is_out ? hw_ep->tx_channel : hw_ep->rx_channel;
 706		if (!dma_channel) {
 707			dma_channel = dma_controller->channel_alloc(
 708					dma_controller, hw_ep, is_out);
 709			if (is_out)
 710				hw_ep->tx_channel = dma_channel;
 711			else
 712				hw_ep->rx_channel = dma_channel;
 713		}
 714	} else
 715		dma_channel = NULL;
 716
 717	/* make sure we clear DMAEnab, autoSet bits from previous run */
 718
 719	/* OUT/transmit/EP0 or IN/receive? */
 720	if (is_out) {
 721		u16	csr;
 722		u16	int_txe;
 723		u16	load_count;
 724
 725		csr = musb_readw(epio, MUSB_TXCSR);
 726
 727		/* disable interrupt in case we flush */
 728		int_txe = musb->intrtxe;
 729		musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum));
 730
 731		/* general endpoint setup */
 732		if (epnum) {
 733			/* flush all old state, set default */
 734			/*
 735			 * We could be flushing valid
 736			 * packets in double buffering
 737			 * case
 738			 */
 739			if (!hw_ep->tx_double_buffered)
 740				musb_h_tx_flush_fifo(hw_ep);
 741
 742			/*
 743			 * We must not clear the DMAMODE bit before or in
 744			 * the same cycle with the DMAENAB bit, so we clear
 745			 * the latter first...
 746			 */
 747			csr &= ~(MUSB_TXCSR_H_NAKTIMEOUT
 748					| MUSB_TXCSR_AUTOSET
 749					| MUSB_TXCSR_DMAENAB
 750					| MUSB_TXCSR_FRCDATATOG
 751					| MUSB_TXCSR_H_RXSTALL
 752					| MUSB_TXCSR_H_ERROR
 753					| MUSB_TXCSR_TXPKTRDY
 754					);
 755			csr |= MUSB_TXCSR_MODE;
 756
 757			if (!hw_ep->tx_double_buffered)
 758				csr |= musb->io.set_toggle(qh, is_out, urb);
 759
 760			musb_writew(epio, MUSB_TXCSR, csr);
 761			/* REVISIT may need to clear FLUSHFIFO ... */
 762			csr &= ~MUSB_TXCSR_DMAMODE;
 763			musb_writew(epio, MUSB_TXCSR, csr);
 764			csr = musb_readw(epio, MUSB_TXCSR);
 765		} else {
 766			/* endpoint 0: just flush */
 767			musb_h_ep0_flush_fifo(hw_ep);
 768		}
 769
 770		/* target addr and (for multipoint) hub addr/port */
 771		if (musb->is_multipoint) {
 772			musb_write_txfunaddr(musb, epnum, qh->addr_reg);
 773			musb_write_txhubaddr(musb, epnum, qh->h_addr_reg);
 774			musb_write_txhubport(musb, epnum, qh->h_port_reg);
 775/* FIXME if !epnum, do the same for RX ... */
 776		} else
 777			musb_writeb(mbase, MUSB_FADDR, qh->addr_reg);
 778
 779		/* protocol/endpoint/interval/NAKlimit */
 780		if (epnum) {
 781			musb_writeb(epio, MUSB_TXTYPE, qh->type_reg);
 782			if (can_bulk_split(musb, qh->type)) {
 783				qh->hb_mult = hw_ep->max_packet_sz_tx
 784						/ packet_sz;
 785				musb_writew(epio, MUSB_TXMAXP, packet_sz
 786					| ((qh->hb_mult) - 1) << 11);
 787			} else {
 788				musb_writew(epio, MUSB_TXMAXP,
 789						qh->maxpacket |
 790						((qh->hb_mult - 1) << 11));
 791			}
 792			musb_writeb(epio, MUSB_TXINTERVAL, qh->intv_reg);
 793		} else {
 794			musb_writeb(epio, MUSB_NAKLIMIT0, qh->intv_reg);
 795			if (musb->is_multipoint)
 796				musb_writeb(epio, MUSB_TYPE0,
 797						qh->type_reg);
 798		}
 799
 800		if (can_bulk_split(musb, qh->type))
 801			load_count = min((u32) hw_ep->max_packet_sz_tx,
 802						len);
 803		else
 804			load_count = min((u32) packet_sz, len);
 805
 806		if (dma_channel && musb_tx_dma_program(dma_controller,
 807					hw_ep, qh, urb, offset, len))
 808			load_count = 0;
 809
 810		if (load_count) {
 811			/* PIO to load FIFO */
 812			qh->segsize = load_count;
 813			if (!buf) {
 814				sg_miter_start(&qh->sg_miter, urb->sg, 1,
 815						SG_MITER_ATOMIC
 816						| SG_MITER_FROM_SG);
 817				if (!sg_miter_next(&qh->sg_miter)) {
 818					dev_err(musb->controller,
 819							"error: sg"
 820							"list empty\n");
 821					sg_miter_stop(&qh->sg_miter);
 822					goto finish;
 823				}
 824				buf = qh->sg_miter.addr + urb->sg->offset +
 825					urb->actual_length;
 826				load_count = min_t(u32, load_count,
 827						qh->sg_miter.length);
 828				musb_write_fifo(hw_ep, load_count, buf);
 829				qh->sg_miter.consumed = load_count;
 830				sg_miter_stop(&qh->sg_miter);
 831			} else
 832				musb_write_fifo(hw_ep, load_count, buf);
 833		}
 834finish:
 835		/* re-enable interrupt */
 836		musb_writew(mbase, MUSB_INTRTXE, int_txe);
 837
 838	/* IN/receive */
 839	} else {
 840		u16 csr = 0;
 841
 842		if (hw_ep->rx_reinit) {
 843			musb_rx_reinit(musb, qh, epnum);
 844			csr |= musb->io.set_toggle(qh, is_out, urb);
 845
 846			if (qh->type == USB_ENDPOINT_XFER_INT)
 847				csr |= MUSB_RXCSR_DISNYET;
 848
 849		} else {
 850			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
 851
 852			if (csr & (MUSB_RXCSR_RXPKTRDY
 853					| MUSB_RXCSR_DMAENAB
 854					| MUSB_RXCSR_H_REQPKT))
 855				ERR("broken !rx_reinit, ep%d csr %04x\n",
 856						hw_ep->epnum, csr);
 857
 858			/* scrub any stale state, leaving toggle alone */
 859			csr &= MUSB_RXCSR_DISNYET;
 860		}
 861
 862		/* kick things off */
 863
 864		if ((is_cppi_enabled(musb) || tusb_dma_omap(musb)) && dma_channel) {
 865			/* Candidate for DMA */
 866			dma_channel->actual_len = 0L;
 867			qh->segsize = len;
 868
 869			/* AUTOREQ is in a DMA register */
 870			musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
 871			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
 872
 873			/*
 874			 * Unless caller treats short RX transfers as
 875			 * errors, we dare not queue multiple transfers.
 876			 */
 877			dma_ok = dma_controller->channel_program(dma_channel,
 878					packet_sz, !(urb->transfer_flags &
 879						     URB_SHORT_NOT_OK),
 880					urb->transfer_dma + offset,
 881					qh->segsize);
 882			if (!dma_ok) {
 883				dma_controller->channel_release(dma_channel);
 884				hw_ep->rx_channel = dma_channel = NULL;
 885			} else
 886				csr |= MUSB_RXCSR_DMAENAB;
 887		}
 888
 889		csr |= MUSB_RXCSR_H_REQPKT;
 890		musb_dbg(musb, "RXCSR%d := %04x", epnum, csr);
 891		musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
 892		csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
 893	}
 894}
 895
 896/* Schedule next QH from musb->in_bulk/out_bulk and move the current qh to
 897 * the end; avoids starvation for other endpoints.
 898 */
 899static void musb_bulk_nak_timeout(struct musb *musb, struct musb_hw_ep *ep,
 900	int is_in)
 901{
 902	struct dma_channel	*dma;
 903	struct urb		*urb;
 904	void __iomem		*mbase = musb->mregs;
 905	void __iomem		*epio = ep->regs;
 906	struct musb_qh		*cur_qh, *next_qh;
 907	u16			rx_csr, tx_csr;
 908	u16			toggle;
 909
 910	musb_ep_select(mbase, ep->epnum);
 911	if (is_in) {
 912		dma = is_dma_capable() ? ep->rx_channel : NULL;
 913
 914		/*
 915		 * Need to stop the transaction by clearing REQPKT first
 916		 * then the NAK Timeout bit ref MUSBMHDRC USB 2.0 HIGH-SPEED
 917		 * DUAL-ROLE CONTROLLER Programmer's Guide, section 9.2.2
 918		 */
 919		rx_csr = musb_readw(epio, MUSB_RXCSR);
 920		rx_csr |= MUSB_RXCSR_H_WZC_BITS;
 921		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
 922		musb_writew(epio, MUSB_RXCSR, rx_csr);
 923		rx_csr &= ~MUSB_RXCSR_DATAERROR;
 924		musb_writew(epio, MUSB_RXCSR, rx_csr);
 925
 926		cur_qh = first_qh(&musb->in_bulk);
 927	} else {
 928		dma = is_dma_capable() ? ep->tx_channel : NULL;
 929
 930		/* clear nak timeout bit */
 931		tx_csr = musb_readw(epio, MUSB_TXCSR);
 932		tx_csr |= MUSB_TXCSR_H_WZC_BITS;
 933		tx_csr &= ~MUSB_TXCSR_H_NAKTIMEOUT;
 934		musb_writew(epio, MUSB_TXCSR, tx_csr);
 935
 936		cur_qh = first_qh(&musb->out_bulk);
 937	}
 938	if (cur_qh) {
 939		urb = next_urb(cur_qh);
 940		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
 941			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
 942			musb->dma_controller->channel_abort(dma);
 943			urb->actual_length += dma->actual_len;
 944			dma->actual_len = 0L;
 945		}
 946		toggle = musb->io.get_toggle(cur_qh, !is_in);
 947		usb_settoggle(urb->dev, cur_qh->epnum, !is_in, toggle ? 1 : 0);
 948
 949		if (is_in) {
 950			/* move cur_qh to end of queue */
 951			list_move_tail(&cur_qh->ring, &musb->in_bulk);
 952
 953			/* get the next qh from musb->in_bulk */
 954			next_qh = first_qh(&musb->in_bulk);
 955
 956			/* set rx_reinit and schedule the next qh */
 957			ep->rx_reinit = 1;
 958		} else {
 959			/* move cur_qh to end of queue */
 960			list_move_tail(&cur_qh->ring, &musb->out_bulk);
 961
 962			/* get the next qh from musb->out_bulk */
 963			next_qh = first_qh(&musb->out_bulk);
 964
 965			/* set tx_reinit and schedule the next qh */
 966			ep->tx_reinit = 1;
 967		}
 968
 969		if (next_qh)
 970			musb_start_urb(musb, is_in, next_qh);
 971	}
 972}
 973
 974/*
 975 * Service the default endpoint (ep0) as host.
 976 * Return true until it's time to start the status stage.
 977 */
 978static bool musb_h_ep0_continue(struct musb *musb, u16 len, struct urb *urb)
 979{
 980	bool			 more = false;
 981	u8			*fifo_dest = NULL;
 982	u16			fifo_count = 0;
 983	struct musb_hw_ep	*hw_ep = musb->control_ep;
 984	struct musb_qh		*qh = hw_ep->in_qh;
 985	struct usb_ctrlrequest	*request;
 986
 987	switch (musb->ep0_stage) {
 988	case MUSB_EP0_IN:
 989		fifo_dest = urb->transfer_buffer + urb->actual_length;
 990		fifo_count = min_t(size_t, len, urb->transfer_buffer_length -
 991				   urb->actual_length);
 992		if (fifo_count < len)
 993			urb->status = -EOVERFLOW;
 994
 995		musb_read_fifo(hw_ep, fifo_count, fifo_dest);
 996
 997		urb->actual_length += fifo_count;
 998		if (len < qh->maxpacket) {
 999			/* always terminate on short read; it's
1000			 * rarely reported as an error.
1001			 */
1002		} else if (urb->actual_length <
1003				urb->transfer_buffer_length)
1004			more = true;
1005		break;
1006	case MUSB_EP0_START:
1007		request = (struct usb_ctrlrequest *) urb->setup_packet;
1008
1009		if (!request->wLength) {
1010			musb_dbg(musb, "start no-DATA");
1011			break;
1012		} else if (request->bRequestType & USB_DIR_IN) {
1013			musb_dbg(musb, "start IN-DATA");
1014			musb->ep0_stage = MUSB_EP0_IN;
1015			more = true;
1016			break;
1017		} else {
1018			musb_dbg(musb, "start OUT-DATA");
1019			musb->ep0_stage = MUSB_EP0_OUT;
1020			more = true;
1021		}
1022		fallthrough;
1023	case MUSB_EP0_OUT:
1024		fifo_count = min_t(size_t, qh->maxpacket,
1025				   urb->transfer_buffer_length -
1026				   urb->actual_length);
1027		if (fifo_count) {
1028			fifo_dest = (u8 *) (urb->transfer_buffer
1029					+ urb->actual_length);
1030			musb_dbg(musb, "Sending %d byte%s to ep0 fifo %p",
1031					fifo_count,
1032					(fifo_count == 1) ? "" : "s",
1033					fifo_dest);
1034			musb_write_fifo(hw_ep, fifo_count, fifo_dest);
1035
1036			urb->actual_length += fifo_count;
1037			more = true;
1038		}
1039		break;
1040	default:
1041		ERR("bogus ep0 stage %d\n", musb->ep0_stage);
1042		break;
1043	}
1044
1045	return more;
1046}
1047
1048/*
1049 * Handle default endpoint interrupt as host. Only called in IRQ time
1050 * from musb_interrupt().
1051 *
1052 * called with controller irqlocked
1053 */
1054irqreturn_t musb_h_ep0_irq(struct musb *musb)
1055{
1056	struct urb		*urb;
1057	u16			csr, len;
1058	int			status = 0;
1059	void __iomem		*mbase = musb->mregs;
1060	struct musb_hw_ep	*hw_ep = musb->control_ep;
1061	void __iomem		*epio = hw_ep->regs;
1062	struct musb_qh		*qh = hw_ep->in_qh;
1063	bool			complete = false;
1064	irqreturn_t		retval = IRQ_NONE;
1065
1066	/* ep0 only has one queue, "in" */
1067	urb = next_urb(qh);
1068
1069	musb_ep_select(mbase, 0);
1070	csr = musb_readw(epio, MUSB_CSR0);
1071	len = (csr & MUSB_CSR0_RXPKTRDY)
1072			? musb_readb(epio, MUSB_COUNT0)
1073			: 0;
1074
1075	musb_dbg(musb, "<== csr0 %04x, qh %p, count %d, urb %p, stage %d",
1076		csr, qh, len, urb, musb->ep0_stage);
1077
1078	/* if we just did status stage, we are done */
1079	if (MUSB_EP0_STATUS == musb->ep0_stage) {
1080		retval = IRQ_HANDLED;
1081		complete = true;
1082	}
1083
1084	/* prepare status */
1085	if (csr & MUSB_CSR0_H_RXSTALL) {
1086		musb_dbg(musb, "STALLING ENDPOINT");
1087		status = -EPIPE;
1088
1089	} else if (csr & MUSB_CSR0_H_ERROR) {
1090		musb_dbg(musb, "no response, csr0 %04x", csr);
1091		status = -EPROTO;
1092
1093	} else if (csr & MUSB_CSR0_H_NAKTIMEOUT) {
1094		musb_dbg(musb, "control NAK timeout");
1095
1096		/* NOTE:  this code path would be a good place to PAUSE a
1097		 * control transfer, if another one is queued, so that
1098		 * ep0 is more likely to stay busy.  That's already done
1099		 * for bulk RX transfers.
1100		 *
1101		 * if (qh->ring.next != &musb->control), then
1102		 * we have a candidate... NAKing is *NOT* an error
1103		 */
1104		musb_writew(epio, MUSB_CSR0, 0);
1105		retval = IRQ_HANDLED;
1106	}
1107
1108	if (status) {
1109		musb_dbg(musb, "aborting");
1110		retval = IRQ_HANDLED;
1111		if (urb)
1112			urb->status = status;
1113		complete = true;
1114
1115		/* use the proper sequence to abort the transfer */
1116		if (csr & MUSB_CSR0_H_REQPKT) {
1117			csr &= ~MUSB_CSR0_H_REQPKT;
1118			musb_writew(epio, MUSB_CSR0, csr);
1119			csr &= ~MUSB_CSR0_H_NAKTIMEOUT;
1120			musb_writew(epio, MUSB_CSR0, csr);
1121		} else {
1122			musb_h_ep0_flush_fifo(hw_ep);
1123		}
1124
1125		musb_writeb(epio, MUSB_NAKLIMIT0, 0);
1126
1127		/* clear it */
1128		musb_writew(epio, MUSB_CSR0, 0);
1129	}
1130
1131	if (unlikely(!urb)) {
1132		/* stop endpoint since we have no place for its data, this
1133		 * SHOULD NEVER HAPPEN! */
1134		ERR("no URB for end 0\n");
1135
1136		musb_h_ep0_flush_fifo(hw_ep);
1137		goto done;
1138	}
1139
1140	if (!complete) {
1141		/* call common logic and prepare response */
1142		if (musb_h_ep0_continue(musb, len, urb)) {
1143			/* more packets required */
1144			csr = (MUSB_EP0_IN == musb->ep0_stage)
1145				?  MUSB_CSR0_H_REQPKT : MUSB_CSR0_TXPKTRDY;
1146		} else {
1147			/* data transfer complete; perform status phase */
1148			if (usb_pipeout(urb->pipe)
1149					|| !urb->transfer_buffer_length)
1150				csr = MUSB_CSR0_H_STATUSPKT
1151					| MUSB_CSR0_H_REQPKT;
1152			else
1153				csr = MUSB_CSR0_H_STATUSPKT
1154					| MUSB_CSR0_TXPKTRDY;
1155
1156			/* disable ping token in status phase */
1157			csr |= MUSB_CSR0_H_DIS_PING;
1158
1159			/* flag status stage */
1160			musb->ep0_stage = MUSB_EP0_STATUS;
1161
1162			musb_dbg(musb, "ep0 STATUS, csr %04x", csr);
1163
1164		}
1165		musb_writew(epio, MUSB_CSR0, csr);
1166		retval = IRQ_HANDLED;
1167	} else
1168		musb->ep0_stage = MUSB_EP0_IDLE;
1169
1170	/* call completion handler if done */
1171	if (complete)
1172		musb_advance_schedule(musb, urb, hw_ep, 1);
1173done:
1174	return retval;
1175}
1176
1177
1178#ifdef CONFIG_USB_INVENTRA_DMA
1179
1180/* Host side TX (OUT) using Mentor DMA works as follows:
1181	submit_urb ->
1182		- if queue was empty, Program Endpoint
1183		- ... which starts DMA to fifo in mode 1 or 0
1184
1185	DMA Isr (transfer complete) -> TxAvail()
1186		- Stop DMA (~DmaEnab)	(<--- Alert ... currently happens
1187					only in musb_cleanup_urb)
1188		- TxPktRdy has to be set in mode 0 or for
1189			short packets in mode 1.
1190*/
1191
1192#endif
1193
1194/* Service a Tx-Available or dma completion irq for the endpoint */
1195void musb_host_tx(struct musb *musb, u8 epnum)
1196{
1197	int			pipe;
1198	bool			done = false;
1199	u16			tx_csr;
1200	size_t			length = 0;
1201	size_t			offset = 0;
1202	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1203	void __iomem		*epio = hw_ep->regs;
1204	struct musb_qh		*qh = hw_ep->out_qh;
1205	struct urb		*urb = next_urb(qh);
1206	u32			status = 0;
1207	void __iomem		*mbase = musb->mregs;
1208	struct dma_channel	*dma;
1209	bool			transfer_pending = false;
1210
1211	musb_ep_select(mbase, epnum);
1212	tx_csr = musb_readw(epio, MUSB_TXCSR);
1213
1214	/* with CPPI, DMA sometimes triggers "extra" irqs */
1215	if (!urb) {
1216		musb_dbg(musb, "extra TX%d ready, csr %04x", epnum, tx_csr);
1217		return;
1218	}
1219
1220	pipe = urb->pipe;
1221	dma = is_dma_capable() ? hw_ep->tx_channel : NULL;
1222	trace_musb_urb_tx(musb, urb);
1223	musb_dbg(musb, "OUT/TX%d end, csr %04x%s", epnum, tx_csr,
1224			dma ? ", dma" : "");
1225
1226	/* check for errors */
1227	if (tx_csr & MUSB_TXCSR_H_RXSTALL) {
1228		/* dma was disabled, fifo flushed */
1229		musb_dbg(musb, "TX end %d stall", epnum);
1230
1231		/* stall; record URB status */
1232		status = -EPIPE;
1233
1234	} else if (tx_csr & MUSB_TXCSR_H_ERROR) {
1235		/* (NON-ISO) dma was disabled, fifo flushed */
1236		musb_dbg(musb, "TX 3strikes on ep=%d", epnum);
1237
1238		status = -ETIMEDOUT;
1239
1240	} else if (tx_csr & MUSB_TXCSR_H_NAKTIMEOUT) {
1241		if (USB_ENDPOINT_XFER_BULK == qh->type && qh->mux == 1
1242				&& !list_is_singular(&musb->out_bulk)) {
1243			musb_dbg(musb, "NAK timeout on TX%d ep", epnum);
1244			musb_bulk_nak_timeout(musb, hw_ep, 0);
1245		} else {
1246			musb_dbg(musb, "TX ep%d device not responding", epnum);
1247			/* NOTE:  this code path would be a good place to PAUSE a
1248			 * transfer, if there's some other (nonperiodic) tx urb
1249			 * that could use this fifo.  (dma complicates it...)
1250			 * That's already done for bulk RX transfers.
1251			 *
1252			 * if (bulk && qh->ring.next != &musb->out_bulk), then
1253			 * we have a candidate... NAKing is *NOT* an error
1254			 */
1255			musb_ep_select(mbase, epnum);
1256			musb_writew(epio, MUSB_TXCSR,
1257					MUSB_TXCSR_H_WZC_BITS
1258					| MUSB_TXCSR_TXPKTRDY);
1259		}
1260		return;
1261	}
1262
1263done:
1264	if (status) {
1265		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1266			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1267			musb->dma_controller->channel_abort(dma);
1268		}
1269
1270		/* do the proper sequence to abort the transfer in the
1271		 * usb core; the dma engine should already be stopped.
1272		 */
1273		musb_h_tx_flush_fifo(hw_ep);
1274		tx_csr &= ~(MUSB_TXCSR_AUTOSET
1275				| MUSB_TXCSR_DMAENAB
1276				| MUSB_TXCSR_H_ERROR
1277				| MUSB_TXCSR_H_RXSTALL
1278				| MUSB_TXCSR_H_NAKTIMEOUT
1279				);
1280
1281		musb_ep_select(mbase, epnum);
1282		musb_writew(epio, MUSB_TXCSR, tx_csr);
1283		/* REVISIT may need to clear FLUSHFIFO ... */
1284		musb_writew(epio, MUSB_TXCSR, tx_csr);
1285		musb_writeb(epio, MUSB_TXINTERVAL, 0);
1286
1287		done = true;
1288	}
1289
1290	/* second cppi case */
1291	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1292		musb_dbg(musb, "extra TX%d ready, csr %04x", epnum, tx_csr);
1293		return;
1294	}
1295
1296	if (is_dma_capable() && dma && !status) {
1297		/*
1298		 * DMA has completed.  But if we're using DMA mode 1 (multi
1299		 * packet DMA), we need a terminal TXPKTRDY interrupt before
1300		 * we can consider this transfer completed, lest we trash
1301		 * its last packet when writing the next URB's data.  So we
1302		 * switch back to mode 0 to get that interrupt; we'll come
1303		 * back here once it happens.
1304		 */
1305		if (tx_csr & MUSB_TXCSR_DMAMODE) {
1306			/*
1307			 * We shouldn't clear DMAMODE with DMAENAB set; so
1308			 * clear them in a safe order.  That should be OK
1309			 * once TXPKTRDY has been set (and I've never seen
1310			 * it being 0 at this moment -- DMA interrupt latency
1311			 * is significant) but if it hasn't been then we have
1312			 * no choice but to stop being polite and ignore the
1313			 * programmer's guide... :-)
1314			 *
1315			 * Note that we must write TXCSR with TXPKTRDY cleared
1316			 * in order not to re-trigger the packet send (this bit
1317			 * can't be cleared by CPU), and there's another caveat:
1318			 * TXPKTRDY may be set shortly and then cleared in the
1319			 * double-buffered FIFO mode, so we do an extra TXCSR
1320			 * read for debouncing...
1321			 */
1322			tx_csr &= musb_readw(epio, MUSB_TXCSR);
1323			if (tx_csr & MUSB_TXCSR_TXPKTRDY) {
1324				tx_csr &= ~(MUSB_TXCSR_DMAENAB |
1325					    MUSB_TXCSR_TXPKTRDY);
1326				musb_writew(epio, MUSB_TXCSR,
1327					    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1328			}
1329			tx_csr &= ~(MUSB_TXCSR_DMAMODE |
1330				    MUSB_TXCSR_TXPKTRDY);
1331			musb_writew(epio, MUSB_TXCSR,
1332				    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1333
1334			/*
1335			 * There is no guarantee that we'll get an interrupt
1336			 * after clearing DMAMODE as we might have done this
1337			 * too late (after TXPKTRDY was cleared by controller).
1338			 * Re-read TXCSR as we have spoiled its previous value.
1339			 */
1340			tx_csr = musb_readw(epio, MUSB_TXCSR);
1341		}
1342
1343		/*
1344		 * We may get here from a DMA completion or TXPKTRDY interrupt.
1345		 * In any case, we must check the FIFO status here and bail out
1346		 * only if the FIFO still has data -- that should prevent the
1347		 * "missed" TXPKTRDY interrupts and deal with double-buffered
1348		 * FIFO mode too...
1349		 */
1350		if (tx_csr & (MUSB_TXCSR_FIFONOTEMPTY | MUSB_TXCSR_TXPKTRDY)) {
1351			musb_dbg(musb,
1352				"DMA complete but FIFO not empty, CSR %04x",
1353				tx_csr);
1354			return;
1355		}
1356	}
1357
1358	if (!status || dma || usb_pipeisoc(pipe)) {
1359		if (dma)
1360			length = dma->actual_len;
1361		else
1362			length = qh->segsize;
1363		qh->offset += length;
1364
1365		if (usb_pipeisoc(pipe)) {
1366			struct usb_iso_packet_descriptor	*d;
1367
1368			d = urb->iso_frame_desc + qh->iso_idx;
1369			d->actual_length = length;
1370			d->status = status;
1371			if (++qh->iso_idx >= urb->number_of_packets) {
1372				done = true;
1373			} else {
1374				d++;
1375				offset = d->offset;
1376				length = d->length;
1377			}
1378		} else if (dma && urb->transfer_buffer_length == qh->offset) {
1379			done = true;
1380		} else {
1381			/* see if we need to send more data, or ZLP */
1382			if (qh->segsize < qh->maxpacket)
1383				done = true;
1384			else if (qh->offset == urb->transfer_buffer_length
1385					&& !(urb->transfer_flags
1386						& URB_ZERO_PACKET))
1387				done = true;
1388			if (!done) {
1389				offset = qh->offset;
1390				length = urb->transfer_buffer_length - offset;
1391				transfer_pending = true;
1392			}
1393		}
1394	}
1395
1396	/* urb->status != -EINPROGRESS means request has been faulted,
1397	 * so we must abort this transfer after cleanup
1398	 */
1399	if (urb->status != -EINPROGRESS) {
1400		done = true;
1401		if (status == 0)
1402			status = urb->status;
1403	}
1404
1405	if (done) {
1406		/* set status */
1407		urb->status = status;
1408		urb->actual_length = qh->offset;
1409		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_OUT);
1410		return;
1411	} else if ((usb_pipeisoc(pipe) || transfer_pending) && dma) {
1412		if (musb_tx_dma_program(musb->dma_controller, hw_ep, qh, urb,
1413				offset, length)) {
1414			if (is_cppi_enabled(musb) || tusb_dma_omap(musb))
1415				musb_h_tx_dma_start(hw_ep);
1416			return;
1417		}
1418	} else	if (tx_csr & MUSB_TXCSR_DMAENAB) {
1419		musb_dbg(musb, "not complete, but DMA enabled?");
1420		return;
1421	}
1422
1423	/*
1424	 * PIO: start next packet in this URB.
1425	 *
1426	 * REVISIT: some docs say that when hw_ep->tx_double_buffered,
1427	 * (and presumably, FIFO is not half-full) we should write *two*
1428	 * packets before updating TXCSR; other docs disagree...
1429	 */
1430	if (length > qh->maxpacket)
1431		length = qh->maxpacket;
1432	/* Unmap the buffer so that CPU can use it */
1433	usb_hcd_unmap_urb_for_dma(musb->hcd, urb);
1434
1435	/*
1436	 * We need to map sg if the transfer_buffer is
1437	 * NULL.
1438	 */
1439	if (!urb->transfer_buffer) {
1440		/* sg_miter_start is already done in musb_ep_program */
1441		if (!sg_miter_next(&qh->sg_miter)) {
1442			dev_err(musb->controller, "error: sg list empty\n");
1443			sg_miter_stop(&qh->sg_miter);
1444			status = -EINVAL;
1445			goto done;
1446		}
1447		length = min_t(u32, length, qh->sg_miter.length);
1448		musb_write_fifo(hw_ep, length, qh->sg_miter.addr);
1449		qh->sg_miter.consumed = length;
1450		sg_miter_stop(&qh->sg_miter);
1451	} else {
1452		musb_write_fifo(hw_ep, length, urb->transfer_buffer + offset);
1453	}
1454
1455	qh->segsize = length;
1456
1457	musb_ep_select(mbase, epnum);
1458	musb_writew(epio, MUSB_TXCSR,
1459			MUSB_TXCSR_H_WZC_BITS | MUSB_TXCSR_TXPKTRDY);
1460}
1461
1462#ifdef CONFIG_USB_TI_CPPI41_DMA
1463/* Seems to set up ISO for cppi41 and not advance len. See commit c57c41d */
1464static int musb_rx_dma_iso_cppi41(struct dma_controller *dma,
1465				  struct musb_hw_ep *hw_ep,
1466				  struct musb_qh *qh,
1467				  struct urb *urb,
1468				  size_t len)
1469{
1470	struct dma_channel *channel = hw_ep->rx_channel;
1471	void __iomem *epio = hw_ep->regs;
1472	dma_addr_t *buf;
1473	u32 length;
1474	u16 val;
1475
1476	buf = (void *)urb->iso_frame_desc[qh->iso_idx].offset +
1477		(u32)urb->transfer_dma;
1478
1479	length = urb->iso_frame_desc[qh->iso_idx].length;
1480
1481	val = musb_readw(epio, MUSB_RXCSR);
1482	val |= MUSB_RXCSR_DMAENAB;
1483	musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1484
1485	return dma->channel_program(channel, qh->maxpacket, 0,
1486				   (u32)buf, length);
1487}
1488#else
1489static inline int musb_rx_dma_iso_cppi41(struct dma_controller *dma,
1490					 struct musb_hw_ep *hw_ep,
1491					 struct musb_qh *qh,
1492					 struct urb *urb,
1493					 size_t len)
1494{
1495	return false;
1496}
1497#endif
1498
1499#if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_UX500_DMA) || \
1500	defined(CONFIG_USB_TI_CPPI41_DMA)
1501/* Host side RX (IN) using Mentor DMA works as follows:
1502	submit_urb ->
1503		- if queue was empty, ProgramEndpoint
1504		- first IN token is sent out (by setting ReqPkt)
1505	LinuxIsr -> RxReady()
1506	/\	=> first packet is received
1507	|	- Set in mode 0 (DmaEnab, ~ReqPkt)
1508	|		-> DMA Isr (transfer complete) -> RxReady()
1509	|		    - Ack receive (~RxPktRdy), turn off DMA (~DmaEnab)
1510	|		    - if urb not complete, send next IN token (ReqPkt)
1511	|			   |		else complete urb.
1512	|			   |
1513	---------------------------
1514 *
1515 * Nuances of mode 1:
1516 *	For short packets, no ack (+RxPktRdy) is sent automatically
1517 *	(even if AutoClear is ON)
1518 *	For full packets, ack (~RxPktRdy) and next IN token (+ReqPkt) is sent
1519 *	automatically => major problem, as collecting the next packet becomes
1520 *	difficult. Hence mode 1 is not used.
1521 *
1522 * REVISIT
1523 *	All we care about at this driver level is that
1524 *       (a) all URBs terminate with REQPKT cleared and fifo(s) empty;
1525 *       (b) termination conditions are: short RX, or buffer full;
1526 *       (c) fault modes include
1527 *           - iff URB_SHORT_NOT_OK, short RX status is -EREMOTEIO.
1528 *             (and that endpoint's dma queue stops immediately)
1529 *           - overflow (full, PLUS more bytes in the terminal packet)
1530 *
1531 *	So for example, usb-storage sets URB_SHORT_NOT_OK, and would
1532 *	thus be a great candidate for using mode 1 ... for all but the
1533 *	last packet of one URB's transfer.
1534 */
1535static int musb_rx_dma_inventra_cppi41(struct dma_controller *dma,
1536				       struct musb_hw_ep *hw_ep,
1537				       struct musb_qh *qh,
1538				       struct urb *urb,
1539				       size_t len)
1540{
1541	struct dma_channel *channel = hw_ep->rx_channel;
1542	void __iomem *epio = hw_ep->regs;
1543	u16 val;
1544	int pipe;
1545	bool done;
1546
1547	pipe = urb->pipe;
1548
1549	if (usb_pipeisoc(pipe)) {
1550		struct usb_iso_packet_descriptor *d;
1551
1552		d = urb->iso_frame_desc + qh->iso_idx;
1553		d->actual_length = len;
1554
1555		/* even if there was an error, we did the dma
1556		 * for iso_frame_desc->length
1557		 */
1558		if (d->status != -EILSEQ && d->status != -EOVERFLOW)
1559			d->status = 0;
1560
1561		if (++qh->iso_idx >= urb->number_of_packets) {
1562			done = true;
1563		} else {
1564			/* REVISIT: Why ignore return value here? */
1565			if (musb_dma_cppi41(hw_ep->musb))
1566				done = musb_rx_dma_iso_cppi41(dma, hw_ep, qh,
1567							      urb, len);
1568			done = false;
1569		}
1570
1571	} else  {
1572		/* done if urb buffer is full or short packet is recd */
1573		done = (urb->actual_length + len >=
1574			urb->transfer_buffer_length
1575			|| channel->actual_len < qh->maxpacket
1576			|| channel->rx_packet_done);
1577	}
1578
1579	/* send IN token for next packet, without AUTOREQ */
1580	if (!done) {
1581		val = musb_readw(epio, MUSB_RXCSR);
1582		val |= MUSB_RXCSR_H_REQPKT;
1583		musb_writew(epio, MUSB_RXCSR, MUSB_RXCSR_H_WZC_BITS | val);
1584	}
1585
1586	return done;
1587}
1588
1589/* Disadvantage of using mode 1:
1590 *	It's basically usable only for mass storage class; essentially all
1591 *	other protocols also terminate transfers on short packets.
1592 *
1593 * Details:
1594 *	An extra IN token is sent at the end of the transfer (due to AUTOREQ)
1595 *	If you try to use mode 1 for (transfer_buffer_length - 512), and try
1596 *	to use the extra IN token to grab the last packet using mode 0, then
1597 *	the problem is that you cannot be sure when the device will send the
1598 *	last packet and RxPktRdy set. Sometimes the packet is recd too soon
1599 *	such that it gets lost when RxCSR is re-set at the end of the mode 1
1600 *	transfer, while sometimes it is recd just a little late so that if you
1601 *	try to configure for mode 0 soon after the mode 1 transfer is
1602 *	completed, you will find rxcount 0. Okay, so you might think why not
1603 *	wait for an interrupt when the pkt is recd. Well, you won't get any!
1604 */
1605static int musb_rx_dma_in_inventra_cppi41(struct dma_controller *dma,
1606					  struct musb_hw_ep *hw_ep,
1607					  struct musb_qh *qh,
1608					  struct urb *urb,
1609					  size_t len,
1610					  u8 iso_err)
1611{
1612	struct musb *musb = hw_ep->musb;
1613	void __iomem *epio = hw_ep->regs;
1614	struct dma_channel *channel = hw_ep->rx_channel;
1615	u16 rx_count, val;
1616	int length, pipe, done;
1617	dma_addr_t buf;
1618
1619	rx_count = musb_readw(epio, MUSB_RXCOUNT);
1620	pipe = urb->pipe;
1621
1622	if (usb_pipeisoc(pipe)) {
1623		int d_status = 0;
1624		struct usb_iso_packet_descriptor *d;
1625
1626		d = urb->iso_frame_desc + qh->iso_idx;
1627
1628		if (iso_err) {
1629			d_status = -EILSEQ;
1630			urb->error_count++;
1631		}
1632		if (rx_count > d->length) {
1633			if (d_status == 0) {
1634				d_status = -EOVERFLOW;
1635				urb->error_count++;
1636			}
1637			musb_dbg(musb, "** OVERFLOW %d into %d",
1638				rx_count, d->length);
1639
1640			length = d->length;
1641		} else
1642			length = rx_count;
1643		d->status = d_status;
1644		buf = urb->transfer_dma + d->offset;
1645	} else {
1646		length = rx_count;
1647		buf = urb->transfer_dma + urb->actual_length;
1648	}
1649
1650	channel->desired_mode = 0;
1651#ifdef USE_MODE1
1652	/* because of the issue below, mode 1 will
1653	 * only rarely behave with correct semantics.
1654	 */
1655	if ((urb->transfer_flags & URB_SHORT_NOT_OK)
1656	    && (urb->transfer_buffer_length - urb->actual_length)
1657	    > qh->maxpacket)
1658		channel->desired_mode = 1;
1659	if (rx_count < hw_ep->max_packet_sz_rx) {
1660		length = rx_count;
1661		channel->desired_mode = 0;
1662	} else {
1663		length = urb->transfer_buffer_length;
1664	}
1665#endif
1666
1667	/* See comments above on disadvantages of using mode 1 */
1668	val = musb_readw(epio, MUSB_RXCSR);
1669	val &= ~MUSB_RXCSR_H_REQPKT;
1670
1671	if (channel->desired_mode == 0)
1672		val &= ~MUSB_RXCSR_H_AUTOREQ;
1673	else
1674		val |= MUSB_RXCSR_H_AUTOREQ;
1675	val |= MUSB_RXCSR_DMAENAB;
1676
1677	/* autoclear shouldn't be set in high bandwidth */
1678	if (qh->hb_mult == 1)
1679		val |= MUSB_RXCSR_AUTOCLEAR;
1680
1681	musb_writew(epio, MUSB_RXCSR, MUSB_RXCSR_H_WZC_BITS | val);
1682
1683	/* REVISIT if when actual_length != 0,
1684	 * transfer_buffer_length needs to be
1685	 * adjusted first...
1686	 */
1687	done = dma->channel_program(channel, qh->maxpacket,
1688				   channel->desired_mode,
1689				   buf, length);
1690
1691	if (!done) {
1692		dma->channel_release(channel);
1693		hw_ep->rx_channel = NULL;
1694		channel = NULL;
1695		val = musb_readw(epio, MUSB_RXCSR);
1696		val &= ~(MUSB_RXCSR_DMAENAB
1697			 | MUSB_RXCSR_H_AUTOREQ
1698			 | MUSB_RXCSR_AUTOCLEAR);
1699		musb_writew(epio, MUSB_RXCSR, val);
1700	}
1701
1702	return done;
1703}
1704#else
1705static inline int musb_rx_dma_inventra_cppi41(struct dma_controller *dma,
1706					      struct musb_hw_ep *hw_ep,
1707					      struct musb_qh *qh,
1708					      struct urb *urb,
1709					      size_t len)
1710{
1711	return false;
1712}
1713
1714static inline int musb_rx_dma_in_inventra_cppi41(struct dma_controller *dma,
1715						 struct musb_hw_ep *hw_ep,
1716						 struct musb_qh *qh,
1717						 struct urb *urb,
1718						 size_t len,
1719						 u8 iso_err)
1720{
1721	return false;
1722}
1723#endif
1724
1725/*
1726 * Service an RX interrupt for the given IN endpoint; docs cover bulk, iso,
1727 * and high-bandwidth IN transfer cases.
1728 */
1729void musb_host_rx(struct musb *musb, u8 epnum)
1730{
1731	struct urb		*urb;
1732	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1733	struct dma_controller	*c = musb->dma_controller;
1734	void __iomem		*epio = hw_ep->regs;
1735	struct musb_qh		*qh = hw_ep->in_qh;
1736	size_t			xfer_len;
1737	void __iomem		*mbase = musb->mregs;
1738	u16			rx_csr, val;
1739	bool			iso_err = false;
1740	bool			done = false;
1741	u32			status;
1742	struct dma_channel	*dma;
1743	unsigned int sg_flags = SG_MITER_ATOMIC | SG_MITER_TO_SG;
1744
1745	musb_ep_select(mbase, epnum);
1746
1747	urb = next_urb(qh);
1748	dma = is_dma_capable() ? hw_ep->rx_channel : NULL;
1749	status = 0;
1750	xfer_len = 0;
1751
1752	rx_csr = musb_readw(epio, MUSB_RXCSR);
1753	val = rx_csr;
1754
1755	if (unlikely(!urb)) {
1756		/* REVISIT -- THIS SHOULD NEVER HAPPEN ... but, at least
1757		 * usbtest #11 (unlinks) triggers it regularly, sometimes
1758		 * with fifo full.  (Only with DMA??)
1759		 */
1760		musb_dbg(musb, "BOGUS RX%d ready, csr %04x, count %d",
1761			epnum, val, musb_readw(epio, MUSB_RXCOUNT));
1762		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1763		return;
1764	}
1765
1766	trace_musb_urb_rx(musb, urb);
1767
1768	/* check for errors, concurrent stall & unlink is not really
1769	 * handled yet! */
1770	if (rx_csr & MUSB_RXCSR_H_RXSTALL) {
1771		musb_dbg(musb, "RX end %d STALL", epnum);
1772
1773		/* stall; record URB status */
1774		status = -EPIPE;
1775
1776	} else if (rx_csr & MUSB_RXCSR_H_ERROR) {
1777		dev_err(musb->controller, "ep%d RX three-strikes error", epnum);
1778
1779		/*
1780		 * The three-strikes error could only happen when the USB
1781		 * device is not accessible, for example detached or powered
1782		 * off. So return the fatal error -ESHUTDOWN so hopefully the
1783		 * USB device drivers won't immediately resubmit the same URB.
1784		 */
1785		status = -ESHUTDOWN;
1786		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1787
1788		rx_csr &= ~MUSB_RXCSR_H_ERROR;
1789		musb_writew(epio, MUSB_RXCSR, rx_csr);
1790
1791	} else if (rx_csr & MUSB_RXCSR_DATAERROR) {
1792
1793		if (USB_ENDPOINT_XFER_ISOC != qh->type) {
1794			musb_dbg(musb, "RX end %d NAK timeout", epnum);
1795
1796			/* NOTE: NAKing is *NOT* an error, so we want to
1797			 * continue.  Except ... if there's a request for
1798			 * another QH, use that instead of starving it.
1799			 *
1800			 * Devices like Ethernet and serial adapters keep
1801			 * reads posted at all times, which will starve
1802			 * other devices without this logic.
1803			 */
1804			if (usb_pipebulk(urb->pipe)
1805					&& qh->mux == 1
1806					&& !list_is_singular(&musb->in_bulk)) {
1807				musb_bulk_nak_timeout(musb, hw_ep, 1);
1808				return;
1809			}
1810			musb_ep_select(mbase, epnum);
1811			rx_csr |= MUSB_RXCSR_H_WZC_BITS;
1812			rx_csr &= ~MUSB_RXCSR_DATAERROR;
1813			musb_writew(epio, MUSB_RXCSR, rx_csr);
1814
1815			goto finish;
1816		} else {
1817			musb_dbg(musb, "RX end %d ISO data error", epnum);
1818			/* packet error reported later */
1819			iso_err = true;
1820		}
1821	} else if (rx_csr & MUSB_RXCSR_INCOMPRX) {
1822		musb_dbg(musb, "end %d high bandwidth incomplete ISO packet RX",
1823				epnum);
1824		status = -EPROTO;
1825	}
1826
1827	/* faults abort the transfer */
1828	if (status) {
1829		/* clean up dma and collect transfer count */
1830		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1831			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1832			musb->dma_controller->channel_abort(dma);
1833			xfer_len = dma->actual_len;
1834		}
1835		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1836		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1837		done = true;
1838		goto finish;
1839	}
1840
1841	if (unlikely(dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY)) {
1842		/* SHOULD NEVER HAPPEN ... but at least DaVinci has done it */
1843		ERR("RX%d dma busy, csr %04x\n", epnum, rx_csr);
1844		goto finish;
1845	}
1846
1847	/* thorough shutdown for now ... given more precise fault handling
1848	 * and better queueing support, we might keep a DMA pipeline going
1849	 * while processing this irq for earlier completions.
1850	 */
1851
1852	/* FIXME this is _way_ too much in-line logic for Mentor DMA */
1853	if (!musb_dma_inventra(musb) && !musb_dma_ux500(musb) &&
1854	    (rx_csr & MUSB_RXCSR_H_REQPKT)) {
1855		/* REVISIT this happened for a while on some short reads...
1856		 * the cleanup still needs investigation... looks bad...
1857		 * and also duplicates dma cleanup code above ... plus,
1858		 * shouldn't this be the "half full" double buffer case?
1859		 */
1860		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1861			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1862			musb->dma_controller->channel_abort(dma);
1863			xfer_len = dma->actual_len;
1864			done = true;
1865		}
1866
1867		musb_dbg(musb, "RXCSR%d %04x, reqpkt, len %zu%s", epnum, rx_csr,
1868				xfer_len, dma ? ", dma" : "");
1869		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
1870
1871		musb_ep_select(mbase, epnum);
1872		musb_writew(epio, MUSB_RXCSR,
1873				MUSB_RXCSR_H_WZC_BITS | rx_csr);
1874	}
1875
1876	if (dma && (rx_csr & MUSB_RXCSR_DMAENAB)) {
1877		xfer_len = dma->actual_len;
1878
1879		val &= ~(MUSB_RXCSR_DMAENAB
1880			| MUSB_RXCSR_H_AUTOREQ
1881			| MUSB_RXCSR_AUTOCLEAR
1882			| MUSB_RXCSR_RXPKTRDY);
1883		musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1884
1885		if (musb_dma_inventra(musb) || musb_dma_ux500(musb) ||
1886		    musb_dma_cppi41(musb)) {
1887			    done = musb_rx_dma_inventra_cppi41(c, hw_ep, qh, urb, xfer_len);
1888			    musb_dbg(hw_ep->musb,
1889				    "ep %d dma %s, rxcsr %04x, rxcount %d",
1890				    epnum, done ? "off" : "reset",
1891				    musb_readw(epio, MUSB_RXCSR),
1892				    musb_readw(epio, MUSB_RXCOUNT));
1893		} else {
1894			done = true;
1895		}
1896
1897	} else if (urb->status == -EINPROGRESS) {
1898		/* if no errors, be sure a packet is ready for unloading */
1899		if (unlikely(!(rx_csr & MUSB_RXCSR_RXPKTRDY))) {
1900			status = -EPROTO;
1901			ERR("Rx interrupt with no errors or packet!\n");
1902
1903			/* FIXME this is another "SHOULD NEVER HAPPEN" */
1904
1905/* SCRUB (RX) */
1906			/* do the proper sequence to abort the transfer */
1907			musb_ep_select(mbase, epnum);
1908			val &= ~MUSB_RXCSR_H_REQPKT;
1909			musb_writew(epio, MUSB_RXCSR, val);
1910			goto finish;
1911		}
1912
1913		/* we are expecting IN packets */
1914		if ((musb_dma_inventra(musb) || musb_dma_ux500(musb) ||
1915		    musb_dma_cppi41(musb)) && dma) {
1916			musb_dbg(hw_ep->musb,
1917				"RX%d count %d, buffer 0x%llx len %d/%d",
1918				epnum, musb_readw(epio, MUSB_RXCOUNT),
1919				(unsigned long long) urb->transfer_dma
1920				+ urb->actual_length,
1921				qh->offset,
1922				urb->transfer_buffer_length);
1923
1924			if (musb_rx_dma_in_inventra_cppi41(c, hw_ep, qh, urb,
1925							   xfer_len, iso_err))
1926				goto finish;
1927			else
1928				dev_err(musb->controller, "error: rx_dma failed\n");
1929		}
1930
1931		if (!dma) {
1932			unsigned int received_len;
1933
1934			/* Unmap the buffer so that CPU can use it */
1935			usb_hcd_unmap_urb_for_dma(musb->hcd, urb);
1936
1937			/*
1938			 * We need to map sg if the transfer_buffer is
1939			 * NULL.
1940			 */
1941			if (!urb->transfer_buffer) {
1942				qh->use_sg = true;
1943				sg_miter_start(&qh->sg_miter, urb->sg, 1,
1944						sg_flags);
1945			}
1946
1947			if (qh->use_sg) {
1948				if (!sg_miter_next(&qh->sg_miter)) {
1949					dev_err(musb->controller, "error: sg list empty\n");
1950					sg_miter_stop(&qh->sg_miter);
1951					status = -EINVAL;
1952					done = true;
1953					goto finish;
1954				}
1955				urb->transfer_buffer = qh->sg_miter.addr;
1956				received_len = urb->actual_length;
1957				qh->offset = 0x0;
1958				done = musb_host_packet_rx(musb, urb, epnum,
1959						iso_err);
1960				/* Calculate the number of bytes received */
1961				received_len = urb->actual_length -
1962					received_len;
1963				qh->sg_miter.consumed = received_len;
1964				sg_miter_stop(&qh->sg_miter);
1965			} else {
1966				done = musb_host_packet_rx(musb, urb,
1967						epnum, iso_err);
1968			}
1969			musb_dbg(musb, "read %spacket", done ? "last " : "");
1970		}
1971	}
1972
1973finish:
1974	urb->actual_length += xfer_len;
1975	qh->offset += xfer_len;
1976	if (done) {
1977		if (qh->use_sg) {
1978			qh->use_sg = false;
1979			urb->transfer_buffer = NULL;
1980		}
1981
1982		if (urb->status == -EINPROGRESS)
1983			urb->status = status;
1984		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_IN);
1985	}
1986}
1987
1988/* schedule nodes correspond to peripheral endpoints, like an OHCI QH.
1989 * the software schedule associates multiple such nodes with a given
1990 * host side hardware endpoint + direction; scheduling may activate
1991 * that hardware endpoint.
1992 */
1993static int musb_schedule(
1994	struct musb		*musb,
1995	struct musb_qh		*qh,
1996	int			is_in)
1997{
1998	int			idle = 0;
1999	int			best_diff;
2000	int			best_end, epnum;
2001	struct musb_hw_ep	*hw_ep = NULL;
2002	struct list_head	*head = NULL;
2003	u8			toggle;
2004	u8			txtype;
2005	struct urb		*urb = next_urb(qh);
2006
2007	/* use fixed hardware for control and bulk */
2008	if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
2009		head = &musb->control;
2010		hw_ep = musb->control_ep;
2011		goto success;
2012	}
2013
2014	/* else, periodic transfers get muxed to other endpoints */
2015
2016	/*
2017	 * We know this qh hasn't been scheduled, so all we need to do
2018	 * is choose which hardware endpoint to put it on ...
2019	 *
2020	 * REVISIT what we really want here is a regular schedule tree
2021	 * like e.g. OHCI uses.
2022	 */
2023	best_diff = 4096;
2024	best_end = -1;
2025
2026	for (epnum = 1, hw_ep = musb->endpoints + 1;
2027			epnum < musb->nr_endpoints;
2028			epnum++, hw_ep++) {
2029		int	diff;
2030
2031		if (musb_ep_get_qh(hw_ep, is_in) != NULL)
2032			continue;
2033
2034		if (hw_ep == musb->bulk_ep)
2035			continue;
2036
2037		if (is_in)
2038			diff = hw_ep->max_packet_sz_rx;
2039		else
2040			diff = hw_ep->max_packet_sz_tx;
2041		diff -= (qh->maxpacket * qh->hb_mult);
2042
2043		if (diff >= 0 && best_diff > diff) {
2044
2045			/*
2046			 * Mentor controller has a bug in that if we schedule
2047			 * a BULK Tx transfer on an endpoint that had earlier
2048			 * handled ISOC then the BULK transfer has to start on
2049			 * a zero toggle.  If the BULK transfer starts on a 1
2050			 * toggle then this transfer will fail as the mentor
2051			 * controller starts the Bulk transfer on a 0 toggle
2052			 * irrespective of the programming of the toggle bits
2053			 * in the TXCSR register.  Check for this condition
2054			 * while allocating the EP for a Tx Bulk transfer.  If
2055			 * so skip this EP.
2056			 */
2057			hw_ep = musb->endpoints + epnum;
2058			toggle = usb_gettoggle(urb->dev, qh->epnum, !is_in);
2059			txtype = (musb_readb(hw_ep->regs, MUSB_TXTYPE)
2060					>> 4) & 0x3;
2061			if (!is_in && (qh->type == USB_ENDPOINT_XFER_BULK) &&
2062				toggle && (txtype == USB_ENDPOINT_XFER_ISOC))
2063				continue;
2064
2065			best_diff = diff;
2066			best_end = epnum;
2067		}
2068	}
2069	/* use bulk reserved ep1 if no other ep is free */
2070	if (best_end < 0 && qh->type == USB_ENDPOINT_XFER_BULK) {
2071		hw_ep = musb->bulk_ep;
2072		if (is_in)
2073			head = &musb->in_bulk;
2074		else
2075			head = &musb->out_bulk;
2076
2077		/* Enable bulk RX/TX NAK timeout scheme when bulk requests are
2078		 * multiplexed. This scheme does not work in high speed to full
2079		 * speed scenario as NAK interrupts are not coming from a
2080		 * full speed device connected to a high speed device.
2081		 * NAK timeout interval is 8 (128 uframe or 16ms) for HS and
2082		 * 4 (8 frame or 8ms) for FS device.
2083		 */
2084		if (qh->dev)
2085			qh->intv_reg =
2086				(USB_SPEED_HIGH == qh->dev->speed) ? 8 : 4;
2087		goto success;
2088	} else if (best_end < 0) {
2089		dev_err(musb->controller,
2090				"%s hwep alloc failed for %dx%d\n",
2091				musb_ep_xfertype_string(qh->type),
2092				qh->hb_mult, qh->maxpacket);
2093		return -ENOSPC;
2094	}
2095
2096	idle = 1;
2097	qh->mux = 0;
2098	hw_ep = musb->endpoints + best_end;
2099	musb_dbg(musb, "qh %p periodic slot %d", qh, best_end);
2100success:
2101	if (head) {
2102		idle = list_empty(head);
2103		list_add_tail(&qh->ring, head);
2104		qh->mux = 1;
2105	}
2106	qh->hw_ep = hw_ep;
2107	qh->hep->hcpriv = qh;
2108	if (idle)
2109		musb_start_urb(musb, is_in, qh);
2110	return 0;
2111}
2112
2113static int musb_urb_enqueue(
2114	struct usb_hcd			*hcd,
2115	struct urb			*urb,
2116	gfp_t				mem_flags)
2117{
2118	unsigned long			flags;
2119	struct musb			*musb = hcd_to_musb(hcd);
2120	struct usb_host_endpoint	*hep = urb->ep;
2121	struct musb_qh			*qh;
2122	struct usb_endpoint_descriptor	*epd = &hep->desc;
2123	int				ret;
2124	unsigned			type_reg;
2125	unsigned			interval;
2126
2127	/* host role must be active */
2128	if (!is_host_active(musb) || !musb->is_active)
2129		return -ENODEV;
2130
2131	trace_musb_urb_enq(musb, urb);
2132
2133	spin_lock_irqsave(&musb->lock, flags);
2134	ret = usb_hcd_link_urb_to_ep(hcd, urb);
2135	qh = ret ? NULL : hep->hcpriv;
2136	if (qh)
2137		urb->hcpriv = qh;
2138	spin_unlock_irqrestore(&musb->lock, flags);
2139
2140	/* DMA mapping was already done, if needed, and this urb is on
2141	 * hep->urb_list now ... so we're done, unless hep wasn't yet
2142	 * scheduled onto a live qh.
2143	 *
2144	 * REVISIT best to keep hep->hcpriv valid until the endpoint gets
2145	 * disabled, testing for empty qh->ring and avoiding qh setup costs
2146	 * except for the first urb queued after a config change.
2147	 */
2148	if (qh || ret)
2149		return ret;
2150
2151	/* Allocate and initialize qh, minimizing the work done each time
2152	 * hw_ep gets reprogrammed, or with irqs blocked.  Then schedule it.
2153	 *
2154	 * REVISIT consider a dedicated qh kmem_cache, so it's harder
2155	 * for bugs in other kernel code to break this driver...
2156	 */
2157	qh = kzalloc(sizeof *qh, mem_flags);
2158	if (!qh) {
2159		spin_lock_irqsave(&musb->lock, flags);
2160		usb_hcd_unlink_urb_from_ep(hcd, urb);
2161		spin_unlock_irqrestore(&musb->lock, flags);
2162		return -ENOMEM;
2163	}
2164
2165	qh->hep = hep;
2166	qh->dev = urb->dev;
2167	INIT_LIST_HEAD(&qh->ring);
2168	qh->is_ready = 1;
2169
2170	qh->maxpacket = usb_endpoint_maxp(epd);
2171	qh->type = usb_endpoint_type(epd);
2172
2173	/* Bits 11 & 12 of wMaxPacketSize encode high bandwidth multiplier.
2174	 * Some musb cores don't support high bandwidth ISO transfers; and
2175	 * we don't (yet!) support high bandwidth interrupt transfers.
2176	 */
2177	qh->hb_mult = usb_endpoint_maxp_mult(epd);
2178	if (qh->hb_mult > 1) {
2179		int ok = (qh->type == USB_ENDPOINT_XFER_ISOC);
2180
2181		if (ok)
2182			ok = (usb_pipein(urb->pipe) && musb->hb_iso_rx)
2183				|| (usb_pipeout(urb->pipe) && musb->hb_iso_tx);
2184		if (!ok) {
2185			dev_err(musb->controller,
2186				"high bandwidth %s (%dx%d) not supported\n",
2187				musb_ep_xfertype_string(qh->type),
2188				qh->hb_mult, qh->maxpacket & 0x7ff);
2189			ret = -EMSGSIZE;
2190			goto done;
2191		}
2192		qh->maxpacket &= 0x7ff;
2193	}
2194
2195	qh->epnum = usb_endpoint_num(epd);
2196
2197	/* NOTE: urb->dev->devnum is wrong during SET_ADDRESS */
2198	qh->addr_reg = (u8) usb_pipedevice(urb->pipe);
2199
2200	/* precompute rxtype/txtype/type0 register */
2201	type_reg = (qh->type << 4) | qh->epnum;
2202	switch (urb->dev->speed) {
2203	case USB_SPEED_LOW:
2204		type_reg |= 0xc0;
2205		break;
2206	case USB_SPEED_FULL:
2207		type_reg |= 0x80;
2208		break;
2209	default:
2210		type_reg |= 0x40;
2211	}
2212	qh->type_reg = type_reg;
2213
2214	/* Precompute RXINTERVAL/TXINTERVAL register */
2215	switch (qh->type) {
2216	case USB_ENDPOINT_XFER_INT:
2217		/*
2218		 * Full/low speeds use the  linear encoding,
2219		 * high speed uses the logarithmic encoding.
2220		 */
2221		if (urb->dev->speed <= USB_SPEED_FULL) {
2222			interval = max_t(u8, epd->bInterval, 1);
2223			break;
2224		}
2225		fallthrough;
2226	case USB_ENDPOINT_XFER_ISOC:
2227		/* ISO always uses logarithmic encoding */
2228		interval = min_t(u8, epd->bInterval, 16);
2229		break;
2230	default:
2231		/* REVISIT we actually want to use NAK limits, hinting to the
2232		 * transfer scheduling logic to try some other qh, e.g. try
2233		 * for 2 msec first:
2234		 *
2235		 * interval = (USB_SPEED_HIGH == urb->dev->speed) ? 16 : 2;
2236		 *
2237		 * The downside of disabling this is that transfer scheduling
2238		 * gets VERY unfair for nonperiodic transfers; a misbehaving
2239		 * peripheral could make that hurt.  That's perfectly normal
2240		 * for reads from network or serial adapters ... so we have
2241		 * partial NAKlimit support for bulk RX.
2242		 *
2243		 * The upside of disabling it is simpler transfer scheduling.
2244		 */
2245		interval = 0;
2246	}
2247	qh->intv_reg = interval;
2248
2249	/* precompute addressing for external hub/tt ports */
2250	if (musb->is_multipoint) {
2251		struct usb_device	*parent = urb->dev->parent;
2252
2253		if (parent != hcd->self.root_hub) {
2254			qh->h_addr_reg = (u8) parent->devnum;
2255
2256			/* set up tt info if needed */
2257			if (urb->dev->tt) {
2258				qh->h_port_reg = (u8) urb->dev->ttport;
2259				if (urb->dev->tt->hub)
2260					qh->h_addr_reg =
2261						(u8) urb->dev->tt->hub->devnum;
2262				if (urb->dev->tt->multi)
2263					qh->h_addr_reg |= 0x80;
2264			}
2265		}
2266	}
2267
2268	/* invariant: hep->hcpriv is null OR the qh that's already scheduled.
2269	 * until we get real dma queues (with an entry for each urb/buffer),
2270	 * we only have work to do in the former case.
2271	 */
2272	spin_lock_irqsave(&musb->lock, flags);
2273	if (hep->hcpriv || !next_urb(qh)) {
2274		/* some concurrent activity submitted another urb to hep...
2275		 * odd, rare, error prone, but legal.
2276		 */
2277		kfree(qh);
2278		qh = NULL;
2279		ret = 0;
2280	} else
2281		ret = musb_schedule(musb, qh,
2282				epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK);
2283
2284	if (ret == 0) {
2285		urb->hcpriv = qh;
2286		/* FIXME set urb->start_frame for iso/intr, it's tested in
2287		 * musb_start_urb(), but otherwise only konicawc cares ...
2288		 */
2289	}
2290	spin_unlock_irqrestore(&musb->lock, flags);
2291
2292done:
2293	if (ret != 0) {
2294		spin_lock_irqsave(&musb->lock, flags);
2295		usb_hcd_unlink_urb_from_ep(hcd, urb);
2296		spin_unlock_irqrestore(&musb->lock, flags);
2297		kfree(qh);
2298	}
2299	return ret;
2300}
2301
2302
2303/*
2304 * abort a transfer that's at the head of a hardware queue.
2305 * called with controller locked, irqs blocked
2306 * that hardware queue advances to the next transfer, unless prevented
2307 */
2308static int musb_cleanup_urb(struct urb *urb, struct musb_qh *qh)
2309{
2310	struct musb_hw_ep	*ep = qh->hw_ep;
2311	struct musb		*musb = ep->musb;
2312	void __iomem		*epio = ep->regs;
2313	unsigned		hw_end = ep->epnum;
2314	void __iomem		*regs = ep->musb->mregs;
2315	int			is_in = usb_pipein(urb->pipe);
2316	int			status = 0;
2317	u16			csr;
2318	struct dma_channel	*dma = NULL;
2319
2320	musb_ep_select(regs, hw_end);
2321
2322	if (is_dma_capable()) {
2323		dma = is_in ? ep->rx_channel : ep->tx_channel;
2324		if (dma) {
2325			status = ep->musb->dma_controller->channel_abort(dma);
2326			musb_dbg(musb, "abort %cX%d DMA for urb %p --> %d",
2327				is_in ? 'R' : 'T', ep->epnum,
2328				urb, status);
2329			urb->actual_length += dma->actual_len;
2330		}
2331	}
2332
2333	/* turn off DMA requests, discard state, stop polling ... */
2334	if (ep->epnum && is_in) {
2335		/* giveback saves bulk toggle */
2336		csr = musb_h_flush_rxfifo(ep, 0);
2337
2338		/* clear the endpoint's irq status here to avoid bogus irqs */
2339		if (is_dma_capable() && dma)
2340			musb_platform_clear_ep_rxintr(musb, ep->epnum);
2341	} else if (ep->epnum) {
2342		musb_h_tx_flush_fifo(ep);
2343		csr = musb_readw(epio, MUSB_TXCSR);
2344		csr &= ~(MUSB_TXCSR_AUTOSET
2345			| MUSB_TXCSR_DMAENAB
2346			| MUSB_TXCSR_H_RXSTALL
2347			| MUSB_TXCSR_H_NAKTIMEOUT
2348			| MUSB_TXCSR_H_ERROR
2349			| MUSB_TXCSR_TXPKTRDY);
2350		musb_writew(epio, MUSB_TXCSR, csr);
2351		/* REVISIT may need to clear FLUSHFIFO ... */
2352		musb_writew(epio, MUSB_TXCSR, csr);
2353		/* flush cpu writebuffer */
2354		csr = musb_readw(epio, MUSB_TXCSR);
2355	} else  {
2356		musb_h_ep0_flush_fifo(ep);
2357	}
2358	if (status == 0)
2359		musb_advance_schedule(ep->musb, urb, ep, is_in);
2360	return status;
2361}
2362
2363static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
2364{
2365	struct musb		*musb = hcd_to_musb(hcd);
2366	struct musb_qh		*qh;
2367	unsigned long		flags;
2368	int			is_in  = usb_pipein(urb->pipe);
2369	int			ret;
2370
2371	trace_musb_urb_deq(musb, urb);
2372
2373	spin_lock_irqsave(&musb->lock, flags);
2374	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
2375	if (ret)
2376		goto done;
2377
2378	qh = urb->hcpriv;
2379	if (!qh)
2380		goto done;
2381
2382	/*
2383	 * Any URB not actively programmed into endpoint hardware can be
2384	 * immediately given back; that's any URB not at the head of an
2385	 * endpoint queue, unless someday we get real DMA queues.  And even
2386	 * if it's at the head, it might not be known to the hardware...
2387	 *
2388	 * Otherwise abort current transfer, pending DMA, etc.; urb->status
2389	 * has already been updated.  This is a synchronous abort; it'd be
2390	 * OK to hold off until after some IRQ, though.
2391	 *
2392	 * NOTE: qh is invalid unless !list_empty(&hep->urb_list)
2393	 */
2394	if (!qh->is_ready
2395			|| urb->urb_list.prev != &qh->hep->urb_list
2396			|| musb_ep_get_qh(qh->hw_ep, is_in) != qh) {
2397		int	ready = qh->is_ready;
2398
2399		qh->is_ready = 0;
2400		musb_giveback(musb, urb, 0);
2401		qh->is_ready = ready;
2402
2403		/* If nothing else (usually musb_giveback) is using it
2404		 * and its URB list has emptied, recycle this qh.
2405		 */
2406		if (ready && list_empty(&qh->hep->urb_list)) {
2407			musb_ep_set_qh(qh->hw_ep, is_in, NULL);
2408			qh->hep->hcpriv = NULL;
2409			list_del(&qh->ring);
2410			kfree(qh);
2411		}
2412	} else
2413		ret = musb_cleanup_urb(urb, qh);
2414done:
2415	spin_unlock_irqrestore(&musb->lock, flags);
2416	return ret;
2417}
2418
2419/* disable an endpoint */
2420static void
2421musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
2422{
2423	u8			is_in = hep->desc.bEndpointAddress & USB_DIR_IN;
2424	unsigned long		flags;
2425	struct musb		*musb = hcd_to_musb(hcd);
2426	struct musb_qh		*qh;
2427	struct urb		*urb;
2428
2429	spin_lock_irqsave(&musb->lock, flags);
2430
2431	qh = hep->hcpriv;
2432	if (qh == NULL)
2433		goto exit;
2434
2435	/* NOTE: qh is invalid unless !list_empty(&hep->urb_list) */
2436
2437	/* Kick the first URB off the hardware, if needed */
2438	qh->is_ready = 0;
2439	if (musb_ep_get_qh(qh->hw_ep, is_in) == qh) {
2440		urb = next_urb(qh);
2441
2442		/* make software (then hardware) stop ASAP */
2443		if (!urb->unlinked)
2444			urb->status = -ESHUTDOWN;
2445
2446		/* cleanup */
2447		musb_cleanup_urb(urb, qh);
2448
2449		/* Then nuke all the others ... and advance the
2450		 * queue on hw_ep (e.g. bulk ring) when we're done.
2451		 */
2452		while (!list_empty(&hep->urb_list)) {
2453			urb = next_urb(qh);
2454			urb->status = -ESHUTDOWN;
2455			musb_advance_schedule(musb, urb, qh->hw_ep, is_in);
2456		}
2457	} else {
2458		/* Just empty the queue; the hardware is busy with
2459		 * other transfers, and since !qh->is_ready nothing
2460		 * will activate any of these as it advances.
2461		 */
2462		while (!list_empty(&hep->urb_list))
2463			musb_giveback(musb, next_urb(qh), -ESHUTDOWN);
2464
2465		hep->hcpriv = NULL;
2466		list_del(&qh->ring);
2467		kfree(qh);
2468	}
2469exit:
2470	spin_unlock_irqrestore(&musb->lock, flags);
2471}
2472
2473static int musb_h_get_frame_number(struct usb_hcd *hcd)
2474{
2475	struct musb	*musb = hcd_to_musb(hcd);
2476
2477	return musb_readw(musb->mregs, MUSB_FRAME);
2478}
2479
2480static int musb_h_start(struct usb_hcd *hcd)
2481{
2482	struct musb	*musb = hcd_to_musb(hcd);
2483
2484	/* NOTE: musb_start() is called when the hub driver turns
2485	 * on port power, or when (OTG) peripheral starts.
2486	 */
2487	hcd->state = HC_STATE_RUNNING;
2488	musb->port1_status = 0;
2489	return 0;
2490}
2491
2492static void musb_h_stop(struct usb_hcd *hcd)
2493{
2494	musb_stop(hcd_to_musb(hcd));
2495	hcd->state = HC_STATE_HALT;
2496}
2497
2498static int musb_bus_suspend(struct usb_hcd *hcd)
2499{
2500	struct musb	*musb = hcd_to_musb(hcd);
2501	u8		devctl;
2502	int		ret;
2503
2504	ret = musb_port_suspend(musb, true);
2505	if (ret)
2506		return ret;
2507
2508	if (!is_host_active(musb))
2509		return 0;
2510
2511	switch (musb_get_state(musb)) {
2512	case OTG_STATE_A_SUSPEND:
2513		return 0;
2514	case OTG_STATE_A_WAIT_VRISE:
2515		/* ID could be grounded even if there's no device
2516		 * on the other end of the cable.  NOTE that the
2517		 * A_WAIT_VRISE timers are messy with MUSB...
2518		 */
2519		devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
2520		if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
2521			musb_set_state(musb, OTG_STATE_A_WAIT_BCON);
2522		break;
2523	default:
2524		break;
2525	}
2526
2527	if (musb->is_active) {
2528		WARNING("trying to suspend as %s while active\n",
2529			musb_otg_state_string(musb));
2530		return -EBUSY;
2531	} else
2532		return 0;
2533}
2534
2535static int musb_bus_resume(struct usb_hcd *hcd)
2536{
2537	struct musb *musb = hcd_to_musb(hcd);
2538
2539	if (musb->config &&
2540	    musb->config->host_port_deassert_reset_at_resume)
2541		musb_port_reset(musb, false);
2542
2543	return 0;
2544}
2545
2546#ifndef CONFIG_MUSB_PIO_ONLY
2547
2548#define MUSB_USB_DMA_ALIGN 4
2549
2550struct musb_temp_buffer {
2551	void *kmalloc_ptr;
2552	void *old_xfer_buffer;
2553	u8 data[];
2554};
2555
2556static void musb_free_temp_buffer(struct urb *urb)
2557{
2558	enum dma_data_direction dir;
2559	struct musb_temp_buffer *temp;
2560	size_t length;
2561
2562	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
2563		return;
2564
2565	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
2566
2567	temp = container_of(urb->transfer_buffer, struct musb_temp_buffer,
2568			    data);
2569
2570	if (dir == DMA_FROM_DEVICE) {
2571		if (usb_pipeisoc(urb->pipe))
2572			length = urb->transfer_buffer_length;
2573		else
2574			length = urb->actual_length;
2575
2576		memcpy(temp->old_xfer_buffer, temp->data, length);
2577	}
2578	urb->transfer_buffer = temp->old_xfer_buffer;
2579	kfree(temp->kmalloc_ptr);
2580
2581	urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
2582}
2583
2584static int musb_alloc_temp_buffer(struct urb *urb, gfp_t mem_flags)
2585{
2586	enum dma_data_direction dir;
2587	struct musb_temp_buffer *temp;
2588	void *kmalloc_ptr;
2589	size_t kmalloc_size;
2590
2591	if (urb->num_sgs || urb->sg ||
2592	    urb->transfer_buffer_length == 0 ||
2593	    !((uintptr_t)urb->transfer_buffer & (MUSB_USB_DMA_ALIGN - 1)))
2594		return 0;
2595
2596	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
2597
2598	/* Allocate a buffer with enough padding for alignment */
2599	kmalloc_size = urb->transfer_buffer_length +
2600		sizeof(struct musb_temp_buffer) + MUSB_USB_DMA_ALIGN - 1;
2601
2602	kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
2603	if (!kmalloc_ptr)
2604		return -ENOMEM;
2605
2606	/* Position our struct temp_buffer such that data is aligned */
2607	temp = PTR_ALIGN(kmalloc_ptr, MUSB_USB_DMA_ALIGN);
2608
2609
2610	temp->kmalloc_ptr = kmalloc_ptr;
2611	temp->old_xfer_buffer = urb->transfer_buffer;
2612	if (dir == DMA_TO_DEVICE)
2613		memcpy(temp->data, urb->transfer_buffer,
2614		       urb->transfer_buffer_length);
2615	urb->transfer_buffer = temp->data;
2616
2617	urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;
2618
2619	return 0;
2620}
2621
2622static int musb_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
2623				      gfp_t mem_flags)
2624{
2625	struct musb	*musb = hcd_to_musb(hcd);
2626	int ret;
2627
2628	/*
2629	 * The DMA engine in RTL1.8 and above cannot handle
2630	 * DMA addresses that are not aligned to a 4 byte boundary.
2631	 * For such engine implemented (un)map_urb_for_dma hooks.
2632	 * Do not use these hooks for RTL<1.8
2633	 */
2634	if (musb->hwvers < MUSB_HWVERS_1800)
2635		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
2636
2637	ret = musb_alloc_temp_buffer(urb, mem_flags);
2638	if (ret)
2639		return ret;
2640
2641	ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
2642	if (ret)
2643		musb_free_temp_buffer(urb);
2644
2645	return ret;
2646}
2647
2648static void musb_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
2649{
2650	struct musb	*musb = hcd_to_musb(hcd);
2651
2652	usb_hcd_unmap_urb_for_dma(hcd, urb);
2653
2654	/* Do not use this hook for RTL<1.8 (see description above) */
2655	if (musb->hwvers < MUSB_HWVERS_1800)
2656		return;
2657
2658	musb_free_temp_buffer(urb);
2659}
2660#endif /* !CONFIG_MUSB_PIO_ONLY */
2661
2662static const struct hc_driver musb_hc_driver = {
2663	.description		= "musb-hcd",
2664	.product_desc		= "MUSB HDRC host driver",
2665	.hcd_priv_size		= sizeof(struct musb *),
2666	.flags			= HCD_USB2 | HCD_DMA | HCD_MEMORY,
2667
2668	/* not using irq handler or reset hooks from usbcore, since
2669	 * those must be shared with peripheral code for OTG configs
2670	 */
2671
2672	.start			= musb_h_start,
2673	.stop			= musb_h_stop,
2674
2675	.get_frame_number	= musb_h_get_frame_number,
2676
2677	.urb_enqueue		= musb_urb_enqueue,
2678	.urb_dequeue		= musb_urb_dequeue,
2679	.endpoint_disable	= musb_h_disable,
2680
2681#ifndef CONFIG_MUSB_PIO_ONLY
2682	.map_urb_for_dma	= musb_map_urb_for_dma,
2683	.unmap_urb_for_dma	= musb_unmap_urb_for_dma,
2684#endif
2685
2686	.hub_status_data	= musb_hub_status_data,
2687	.hub_control		= musb_hub_control,
2688	.bus_suspend		= musb_bus_suspend,
2689	.bus_resume		= musb_bus_resume,
2690	/* .start_port_reset	= NULL, */
2691	/* .hub_irq_enable	= NULL, */
2692};
2693
2694int musb_host_alloc(struct musb *musb)
2695{
2696	struct device	*dev = musb->controller;
2697
2698	/* usbcore sets dev->driver_data to hcd, and sometimes uses that... */
2699	musb->hcd = usb_create_hcd(&musb_hc_driver, dev, dev_name(dev));
2700	if (!musb->hcd)
2701		return -EINVAL;
2702
2703	*musb->hcd->hcd_priv = (unsigned long) musb;
2704	musb->hcd->self.uses_pio_for_control = 1;
2705	musb->hcd->uses_new_polling = 1;
2706	musb->hcd->has_tt = 1;
2707
2708	return 0;
2709}
2710
2711void musb_host_cleanup(struct musb *musb)
2712{
2713	if (musb->port_mode == MUSB_PERIPHERAL)
2714		return;
2715	usb_remove_hcd(musb->hcd);
2716}
2717
2718void musb_host_free(struct musb *musb)
2719{
2720	usb_put_hcd(musb->hcd);
2721}
2722
2723int musb_host_setup(struct musb *musb, int power_budget)
2724{
2725	int ret;
2726	struct usb_hcd *hcd = musb->hcd;
2727
2728	if (musb->port_mode == MUSB_HOST) {
2729		MUSB_HST_MODE(musb);
2730		musb_set_state(musb, OTG_STATE_A_IDLE);
2731	}
2732
2733	if (musb->xceiv) {
2734		otg_set_host(musb->xceiv->otg, &hcd->self);
2735		musb->xceiv->otg->host = &hcd->self;
2736	} else {
2737		phy_set_mode(musb->phy, PHY_MODE_USB_HOST);
2738	}
2739
2740	/* don't support otg protocols */
2741	hcd->self.otg_port = 0;
2742	hcd->power_budget = 2 * (power_budget ? : 250);
2743	hcd->skip_phy_initialization = 1;
2744
2745	ret = usb_add_hcd(hcd, 0, 0);
2746	if (ret < 0)
2747		return ret;
2748
2749	device_wakeup_enable(hcd->self.controller);
2750	return 0;
2751}
2752
2753void musb_host_resume_root_hub(struct musb *musb)
2754{
2755	usb_hcd_resume_root_hub(musb->hcd);
2756}
2757
2758void musb_host_poke_root_hub(struct musb *musb)
2759{
2760	MUSB_HST_MODE(musb);
2761	if (musb->hcd->status_urb)
2762		usb_hcd_poll_rh_status(musb->hcd);
2763	else
2764		usb_hcd_resume_root_hub(musb->hcd);
2765}
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * MUSB OTG driver host support
   4 *
   5 * Copyright 2005 Mentor Graphics Corporation
   6 * Copyright (C) 2005-2006 by Texas Instruments
   7 * Copyright (C) 2006-2007 Nokia Corporation
   8 * Copyright (C) 2008-2009 MontaVista Software, Inc. <source@mvista.com>
   9 */
  10
  11#include <linux/module.h>
  12#include <linux/kernel.h>
  13#include <linux/delay.h>
  14#include <linux/sched.h>
  15#include <linux/slab.h>
  16#include <linux/errno.h>
  17#include <linux/list.h>
  18#include <linux/dma-mapping.h>
  19
  20#include "musb_core.h"
  21#include "musb_host.h"
  22#include "musb_trace.h"
  23
  24/* MUSB HOST status 22-mar-2006
  25 *
  26 * - There's still lots of partial code duplication for fault paths, so
  27 *   they aren't handled as consistently as they need to be.
  28 *
  29 * - PIO mostly behaved when last tested.
  30 *     + including ep0, with all usbtest cases 9, 10
  31 *     + usbtest 14 (ep0out) doesn't seem to run at all
  32 *     + double buffered OUT/TX endpoints saw stalls(!) with certain usbtest
  33 *       configurations, but otherwise double buffering passes basic tests.
  34 *     + for 2.6.N, for N > ~10, needs API changes for hcd framework.
  35 *
  36 * - DMA (CPPI) ... partially behaves, not currently recommended
  37 *     + about 1/15 the speed of typical EHCI implementations (PCI)
  38 *     + RX, all too often reqpkt seems to misbehave after tx
  39 *     + TX, no known issues (other than evident silicon issue)
  40 *
  41 * - DMA (Mentor/OMAP) ...has at least toggle update problems
  42 *
  43 * - [23-feb-2009] minimal traffic scheduling to avoid bulk RX packet
  44 *   starvation ... nothing yet for TX, interrupt, or bulk.
  45 *
  46 * - Not tested with HNP, but some SRP paths seem to behave.
  47 *
  48 * NOTE 24-August-2006:
  49 *
  50 * - Bulk traffic finally uses both sides of hardware ep1, freeing up an
  51 *   extra endpoint for periodic use enabling hub + keybd + mouse.  That
  52 *   mostly works, except that with "usbnet" it's easy to trigger cases
  53 *   with "ping" where RX loses.  (a) ping to davinci, even "ping -f",
  54 *   fine; but (b) ping _from_ davinci, even "ping -c 1", ICMP RX loses
  55 *   although ARP RX wins.  (That test was done with a full speed link.)
  56 */
  57
  58
  59/*
  60 * NOTE on endpoint usage:
  61 *
  62 * CONTROL transfers all go through ep0.  BULK ones go through dedicated IN
  63 * and OUT endpoints ... hardware is dedicated for those "async" queue(s).
  64 * (Yes, bulk _could_ use more of the endpoints than that, and would even
  65 * benefit from it.)
  66 *
  67 * INTERUPPT and ISOCHRONOUS transfers are scheduled to the other endpoints.
  68 * So far that scheduling is both dumb and optimistic:  the endpoint will be
  69 * "claimed" until its software queue is no longer refilled.  No multiplexing
  70 * of transfers between endpoints, or anything clever.
  71 */
  72
  73struct musb *hcd_to_musb(struct usb_hcd *hcd)
  74{
  75	return *(struct musb **) hcd->hcd_priv;
  76}
  77
  78
  79static void musb_ep_program(struct musb *musb, u8 epnum,
  80			struct urb *urb, int is_out,
  81			u8 *buf, u32 offset, u32 len);
  82
  83/*
  84 * Clear TX fifo. Needed to avoid BABBLE errors.
  85 */
  86static void musb_h_tx_flush_fifo(struct musb_hw_ep *ep)
  87{
  88	struct musb	*musb = ep->musb;
  89	void __iomem	*epio = ep->regs;
  90	u16		csr;
  91	int		retries = 1000;
  92
  93	csr = musb_readw(epio, MUSB_TXCSR);
  94	while (csr & MUSB_TXCSR_FIFONOTEMPTY) {
  95		csr |= MUSB_TXCSR_FLUSHFIFO | MUSB_TXCSR_TXPKTRDY;
  96		musb_writew(epio, MUSB_TXCSR, csr);
  97		csr = musb_readw(epio, MUSB_TXCSR);
  98
  99		/*
 100		 * FIXME: sometimes the tx fifo flush failed, it has been
 101		 * observed during device disconnect on AM335x.
 102		 *
 103		 * To reproduce the issue, ensure tx urb(s) are queued when
 104		 * unplug the usb device which is connected to AM335x usb
 105		 * host port.
 106		 *
 107		 * I found using a usb-ethernet device and running iperf
 108		 * (client on AM335x) has very high chance to trigger it.
 109		 *
 110		 * Better to turn on musb_dbg() in musb_cleanup_urb() with
 111		 * CPPI enabled to see the issue when aborting the tx channel.
 112		 */
 113		if (dev_WARN_ONCE(musb->controller, retries-- < 1,
 114				"Could not flush host TX%d fifo: csr: %04x\n",
 115				ep->epnum, csr))
 116			return;
 117		mdelay(1);
 118	}
 119}
 120
 121static void musb_h_ep0_flush_fifo(struct musb_hw_ep *ep)
 122{
 123	void __iomem	*epio = ep->regs;
 124	u16		csr;
 125	int		retries = 5;
 126
 127	/* scrub any data left in the fifo */
 128	do {
 129		csr = musb_readw(epio, MUSB_TXCSR);
 130		if (!(csr & (MUSB_CSR0_TXPKTRDY | MUSB_CSR0_RXPKTRDY)))
 131			break;
 132		musb_writew(epio, MUSB_TXCSR, MUSB_CSR0_FLUSHFIFO);
 133		csr = musb_readw(epio, MUSB_TXCSR);
 134		udelay(10);
 135	} while (--retries);
 136
 137	WARN(!retries, "Could not flush host TX%d fifo: csr: %04x\n",
 138			ep->epnum, csr);
 139
 140	/* and reset for the next transfer */
 141	musb_writew(epio, MUSB_TXCSR, 0);
 142}
 143
 144/*
 145 * Start transmit. Caller is responsible for locking shared resources.
 146 * musb must be locked.
 147 */
 148static inline void musb_h_tx_start(struct musb_hw_ep *ep)
 149{
 150	u16	txcsr;
 151
 152	/* NOTE: no locks here; caller should lock and select EP */
 153	if (ep->epnum) {
 154		txcsr = musb_readw(ep->regs, MUSB_TXCSR);
 155		txcsr |= MUSB_TXCSR_TXPKTRDY | MUSB_TXCSR_H_WZC_BITS;
 156		musb_writew(ep->regs, MUSB_TXCSR, txcsr);
 157	} else {
 158		txcsr = MUSB_CSR0_H_SETUPPKT | MUSB_CSR0_TXPKTRDY;
 159		musb_writew(ep->regs, MUSB_CSR0, txcsr);
 160	}
 161
 162}
 163
 164static inline void musb_h_tx_dma_start(struct musb_hw_ep *ep)
 165{
 166	u16	txcsr;
 167
 168	/* NOTE: no locks here; caller should lock and select EP */
 169	txcsr = musb_readw(ep->regs, MUSB_TXCSR);
 170	txcsr |= MUSB_TXCSR_DMAENAB | MUSB_TXCSR_H_WZC_BITS;
 171	if (is_cppi_enabled(ep->musb))
 172		txcsr |= MUSB_TXCSR_DMAMODE;
 173	musb_writew(ep->regs, MUSB_TXCSR, txcsr);
 174}
 175
 176static void musb_ep_set_qh(struct musb_hw_ep *ep, int is_in, struct musb_qh *qh)
 177{
 178	if (is_in != 0 || ep->is_shared_fifo)
 179		ep->in_qh  = qh;
 180	if (is_in == 0 || ep->is_shared_fifo)
 181		ep->out_qh = qh;
 182}
 183
 184static struct musb_qh *musb_ep_get_qh(struct musb_hw_ep *ep, int is_in)
 185{
 186	return is_in ? ep->in_qh : ep->out_qh;
 187}
 188
 189/*
 190 * Start the URB at the front of an endpoint's queue
 191 * end must be claimed from the caller.
 192 *
 193 * Context: controller locked, irqs blocked
 194 */
 195static void
 196musb_start_urb(struct musb *musb, int is_in, struct musb_qh *qh)
 197{
 198	u32			len;
 199	void __iomem		*mbase =  musb->mregs;
 200	struct urb		*urb = next_urb(qh);
 201	void			*buf = urb->transfer_buffer;
 202	u32			offset = 0;
 203	struct musb_hw_ep	*hw_ep = qh->hw_ep;
 204	int			epnum = hw_ep->epnum;
 205
 206	/* initialize software qh state */
 207	qh->offset = 0;
 208	qh->segsize = 0;
 209
 210	/* gather right source of data */
 211	switch (qh->type) {
 212	case USB_ENDPOINT_XFER_CONTROL:
 213		/* control transfers always start with SETUP */
 214		is_in = 0;
 215		musb->ep0_stage = MUSB_EP0_START;
 216		buf = urb->setup_packet;
 217		len = 8;
 218		break;
 219	case USB_ENDPOINT_XFER_ISOC:
 220		qh->iso_idx = 0;
 221		qh->frame = 0;
 222		offset = urb->iso_frame_desc[0].offset;
 223		len = urb->iso_frame_desc[0].length;
 224		break;
 225	default:		/* bulk, interrupt */
 226		/* actual_length may be nonzero on retry paths */
 227		buf = urb->transfer_buffer + urb->actual_length;
 228		len = urb->transfer_buffer_length - urb->actual_length;
 229	}
 230
 231	trace_musb_urb_start(musb, urb);
 232
 233	/* Configure endpoint */
 234	musb_ep_set_qh(hw_ep, is_in, qh);
 235	musb_ep_program(musb, epnum, urb, !is_in, buf, offset, len);
 236
 237	/* transmit may have more work: start it when it is time */
 238	if (is_in)
 239		return;
 240
 241	/* determine if the time is right for a periodic transfer */
 242	switch (qh->type) {
 243	case USB_ENDPOINT_XFER_ISOC:
 244	case USB_ENDPOINT_XFER_INT:
 245		musb_dbg(musb, "check whether there's still time for periodic Tx");
 246		/* FIXME this doesn't implement that scheduling policy ...
 247		 * or handle framecounter wrapping
 248		 */
 249		if (1) {	/* Always assume URB_ISO_ASAP */
 250			/* REVISIT the SOF irq handler shouldn't duplicate
 251			 * this code; and we don't init urb->start_frame...
 252			 */
 253			qh->frame = 0;
 254			goto start;
 255		} else {
 256			qh->frame = urb->start_frame;
 257			/* enable SOF interrupt so we can count down */
 258			musb_dbg(musb, "SOF for %d", epnum);
 259#if 1 /* ifndef	CONFIG_ARCH_DAVINCI */
 260			musb_writeb(mbase, MUSB_INTRUSBE, 0xff);
 261#endif
 262		}
 263		break;
 264	default:
 265start:
 266		musb_dbg(musb, "Start TX%d %s", epnum,
 267			hw_ep->tx_channel ? "dma" : "pio");
 268
 269		if (!hw_ep->tx_channel)
 270			musb_h_tx_start(hw_ep);
 271		else if (is_cppi_enabled(musb) || tusb_dma_omap(musb))
 272			musb_h_tx_dma_start(hw_ep);
 273	}
 274}
 275
 276/* Context: caller owns controller lock, IRQs are blocked */
 277static void musb_giveback(struct musb *musb, struct urb *urb, int status)
 278__releases(musb->lock)
 279__acquires(musb->lock)
 280{
 281	trace_musb_urb_gb(musb, urb);
 282
 283	usb_hcd_unlink_urb_from_ep(musb->hcd, urb);
 284	spin_unlock(&musb->lock);
 285	usb_hcd_giveback_urb(musb->hcd, urb, status);
 286	spin_lock(&musb->lock);
 287}
 288
 289/*
 290 * Advance this hardware endpoint's queue, completing the specified URB and
 291 * advancing to either the next URB queued to that qh, or else invalidating
 292 * that qh and advancing to the next qh scheduled after the current one.
 293 *
 294 * Context: caller owns controller lock, IRQs are blocked
 295 */
 296static void musb_advance_schedule(struct musb *musb, struct urb *urb,
 297				  struct musb_hw_ep *hw_ep, int is_in)
 298{
 299	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, is_in);
 300	struct musb_hw_ep	*ep = qh->hw_ep;
 301	int			ready = qh->is_ready;
 302	int			status;
 303	u16			toggle;
 304
 305	status = (urb->status == -EINPROGRESS) ? 0 : urb->status;
 306
 307	/* save toggle eagerly, for paranoia */
 308	switch (qh->type) {
 309	case USB_ENDPOINT_XFER_BULK:
 310	case USB_ENDPOINT_XFER_INT:
 311		toggle = musb->io.get_toggle(qh, !is_in);
 312		usb_settoggle(urb->dev, qh->epnum, !is_in, toggle ? 1 : 0);
 313		break;
 314	case USB_ENDPOINT_XFER_ISOC:
 315		if (status == 0 && urb->error_count)
 316			status = -EXDEV;
 317		break;
 318	}
 319
 320	qh->is_ready = 0;
 321	musb_giveback(musb, urb, status);
 322	qh->is_ready = ready;
 323
 324	/*
 325	 * musb->lock had been unlocked in musb_giveback, so qh may
 326	 * be freed, need to get it again
 327	 */
 328	qh = musb_ep_get_qh(hw_ep, is_in);
 329
 330	/* reclaim resources (and bandwidth) ASAP; deschedule it, and
 331	 * invalidate qh as soon as list_empty(&hep->urb_list)
 332	 */
 333	if (qh && list_empty(&qh->hep->urb_list)) {
 334		struct list_head	*head;
 335		struct dma_controller	*dma = musb->dma_controller;
 336
 337		if (is_in) {
 338			ep->rx_reinit = 1;
 339			if (ep->rx_channel) {
 340				dma->channel_release(ep->rx_channel);
 341				ep->rx_channel = NULL;
 342			}
 343		} else {
 344			ep->tx_reinit = 1;
 345			if (ep->tx_channel) {
 346				dma->channel_release(ep->tx_channel);
 347				ep->tx_channel = NULL;
 348			}
 349		}
 350
 351		/* Clobber old pointers to this qh */
 352		musb_ep_set_qh(ep, is_in, NULL);
 353		qh->hep->hcpriv = NULL;
 354
 355		switch (qh->type) {
 356
 357		case USB_ENDPOINT_XFER_CONTROL:
 358		case USB_ENDPOINT_XFER_BULK:
 359			/* fifo policy for these lists, except that NAKing
 360			 * should rotate a qh to the end (for fairness).
 361			 */
 362			if (qh->mux == 1) {
 363				head = qh->ring.prev;
 364				list_del(&qh->ring);
 365				kfree(qh);
 366				qh = first_qh(head);
 367				break;
 368			}
 369			fallthrough;
 370
 371		case USB_ENDPOINT_XFER_ISOC:
 372		case USB_ENDPOINT_XFER_INT:
 373			/* this is where periodic bandwidth should be
 374			 * de-allocated if it's tracked and allocated;
 375			 * and where we'd update the schedule tree...
 376			 */
 377			kfree(qh);
 378			qh = NULL;
 379			break;
 380		}
 381	}
 382
 383	if (qh != NULL && qh->is_ready) {
 384		musb_dbg(musb, "... next ep%d %cX urb %p",
 385		    hw_ep->epnum, is_in ? 'R' : 'T', next_urb(qh));
 386		musb_start_urb(musb, is_in, qh);
 387	}
 388}
 389
 390static u16 musb_h_flush_rxfifo(struct musb_hw_ep *hw_ep, u16 csr)
 391{
 392	/* we don't want fifo to fill itself again;
 393	 * ignore dma (various models),
 394	 * leave toggle alone (may not have been saved yet)
 395	 */
 396	csr |= MUSB_RXCSR_FLUSHFIFO | MUSB_RXCSR_RXPKTRDY;
 397	csr &= ~(MUSB_RXCSR_H_REQPKT
 398		| MUSB_RXCSR_H_AUTOREQ
 399		| MUSB_RXCSR_AUTOCLEAR);
 400
 401	/* write 2x to allow double buffering */
 402	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
 403	musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
 404
 405	/* flush writebuffer */
 406	return musb_readw(hw_ep->regs, MUSB_RXCSR);
 407}
 408
 409/*
 410 * PIO RX for a packet (or part of it).
 411 */
 412static bool
 413musb_host_packet_rx(struct musb *musb, struct urb *urb, u8 epnum, u8 iso_err)
 414{
 415	u16			rx_count;
 416	u8			*buf;
 417	u16			csr;
 418	bool			done = false;
 419	u32			length;
 420	int			do_flush = 0;
 421	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
 422	void __iomem		*epio = hw_ep->regs;
 423	struct musb_qh		*qh = hw_ep->in_qh;
 424	int			pipe = urb->pipe;
 425	void			*buffer = urb->transfer_buffer;
 426
 427	/* musb_ep_select(mbase, epnum); */
 428	rx_count = musb_readw(epio, MUSB_RXCOUNT);
 429	musb_dbg(musb, "RX%d count %d, buffer %p len %d/%d", epnum, rx_count,
 430			urb->transfer_buffer, qh->offset,
 431			urb->transfer_buffer_length);
 432
 433	/* unload FIFO */
 434	if (usb_pipeisoc(pipe)) {
 435		int					status = 0;
 436		struct usb_iso_packet_descriptor	*d;
 437
 438		if (iso_err) {
 439			status = -EILSEQ;
 440			urb->error_count++;
 441		}
 442
 443		d = urb->iso_frame_desc + qh->iso_idx;
 444		buf = buffer + d->offset;
 445		length = d->length;
 446		if (rx_count > length) {
 447			if (status == 0) {
 448				status = -EOVERFLOW;
 449				urb->error_count++;
 450			}
 451			musb_dbg(musb, "OVERFLOW %d into %d", rx_count, length);
 452			do_flush = 1;
 453		} else
 454			length = rx_count;
 455		urb->actual_length += length;
 456		d->actual_length = length;
 457
 458		d->status = status;
 459
 460		/* see if we are done */
 461		done = (++qh->iso_idx >= urb->number_of_packets);
 462	} else {
 463		/* non-isoch */
 464		buf = buffer + qh->offset;
 465		length = urb->transfer_buffer_length - qh->offset;
 466		if (rx_count > length) {
 467			if (urb->status == -EINPROGRESS)
 468				urb->status = -EOVERFLOW;
 469			musb_dbg(musb, "OVERFLOW %d into %d", rx_count, length);
 470			do_flush = 1;
 471		} else
 472			length = rx_count;
 473		urb->actual_length += length;
 474		qh->offset += length;
 475
 476		/* see if we are done */
 477		done = (urb->actual_length == urb->transfer_buffer_length)
 478			|| (rx_count < qh->maxpacket)
 479			|| (urb->status != -EINPROGRESS);
 480		if (done
 481				&& (urb->status == -EINPROGRESS)
 482				&& (urb->transfer_flags & URB_SHORT_NOT_OK)
 483				&& (urb->actual_length
 484					< urb->transfer_buffer_length))
 485			urb->status = -EREMOTEIO;
 486	}
 487
 488	musb_read_fifo(hw_ep, length, buf);
 489
 490	csr = musb_readw(epio, MUSB_RXCSR);
 491	csr |= MUSB_RXCSR_H_WZC_BITS;
 492	if (unlikely(do_flush))
 493		musb_h_flush_rxfifo(hw_ep, csr);
 494	else {
 495		/* REVISIT this assumes AUTOCLEAR is never set */
 496		csr &= ~(MUSB_RXCSR_RXPKTRDY | MUSB_RXCSR_H_REQPKT);
 497		if (!done)
 498			csr |= MUSB_RXCSR_H_REQPKT;
 499		musb_writew(epio, MUSB_RXCSR, csr);
 500	}
 501
 502	return done;
 503}
 504
 505/* we don't always need to reinit a given side of an endpoint...
 506 * when we do, use tx/rx reinit routine and then construct a new CSR
 507 * to address data toggle, NYET, and DMA or PIO.
 508 *
 509 * it's possible that driver bugs (especially for DMA) or aborting a
 510 * transfer might have left the endpoint busier than it should be.
 511 * the busy/not-empty tests are basically paranoia.
 512 */
 513static void
 514musb_rx_reinit(struct musb *musb, struct musb_qh *qh, u8 epnum)
 515{
 516	struct musb_hw_ep *ep = musb->endpoints + epnum;
 517	u16	csr;
 518
 519	/* NOTE:  we know the "rx" fifo reinit never triggers for ep0.
 520	 * That always uses tx_reinit since ep0 repurposes TX register
 521	 * offsets; the initial SETUP packet is also a kind of OUT.
 522	 */
 523
 524	/* if programmed for Tx, put it in RX mode */
 525	if (ep->is_shared_fifo) {
 526		csr = musb_readw(ep->regs, MUSB_TXCSR);
 527		if (csr & MUSB_TXCSR_MODE) {
 528			musb_h_tx_flush_fifo(ep);
 529			csr = musb_readw(ep->regs, MUSB_TXCSR);
 530			musb_writew(ep->regs, MUSB_TXCSR,
 531				    csr | MUSB_TXCSR_FRCDATATOG);
 532		}
 533
 534		/*
 535		 * Clear the MODE bit (and everything else) to enable Rx.
 536		 * NOTE: we mustn't clear the DMAMODE bit before DMAENAB.
 537		 */
 538		if (csr & MUSB_TXCSR_DMAMODE)
 539			musb_writew(ep->regs, MUSB_TXCSR, MUSB_TXCSR_DMAMODE);
 540		musb_writew(ep->regs, MUSB_TXCSR, 0);
 541
 542	/* scrub all previous state, clearing toggle */
 543	}
 544	csr = musb_readw(ep->regs, MUSB_RXCSR);
 545	if (csr & MUSB_RXCSR_RXPKTRDY)
 546		WARNING("rx%d, packet/%d ready?\n", ep->epnum,
 547			musb_readw(ep->regs, MUSB_RXCOUNT));
 548
 549	musb_h_flush_rxfifo(ep, MUSB_RXCSR_CLRDATATOG);
 550
 551	/* target addr and (for multipoint) hub addr/port */
 552	if (musb->is_multipoint) {
 553		musb_write_rxfunaddr(musb, epnum, qh->addr_reg);
 554		musb_write_rxhubaddr(musb, epnum, qh->h_addr_reg);
 555		musb_write_rxhubport(musb, epnum, qh->h_port_reg);
 556	} else
 557		musb_writeb(musb->mregs, MUSB_FADDR, qh->addr_reg);
 558
 559	/* protocol/endpoint, interval/NAKlimit, i/o size */
 560	musb_writeb(ep->regs, MUSB_RXTYPE, qh->type_reg);
 561	musb_writeb(ep->regs, MUSB_RXINTERVAL, qh->intv_reg);
 562	/* NOTE: bulk combining rewrites high bits of maxpacket */
 563	/* Set RXMAXP with the FIFO size of the endpoint
 564	 * to disable double buffer mode.
 565	 */
 566	musb_writew(ep->regs, MUSB_RXMAXP,
 567			qh->maxpacket | ((qh->hb_mult - 1) << 11));
 568
 569	ep->rx_reinit = 0;
 570}
 571
 572static void musb_tx_dma_set_mode_mentor(struct musb_hw_ep *hw_ep, 
 573					struct musb_qh *qh,
 574					u32 *length, u8 *mode)
 575{
 576	struct dma_channel	*channel = hw_ep->tx_channel;
 577	void __iomem		*epio = hw_ep->regs;
 578	u16			pkt_size = qh->maxpacket;
 579	u16			csr;
 580
 581	if (*length > channel->max_len)
 582		*length = channel->max_len;
 583
 584	csr = musb_readw(epio, MUSB_TXCSR);
 585	if (*length > pkt_size) {
 586		*mode = 1;
 587		csr |= MUSB_TXCSR_DMAMODE | MUSB_TXCSR_DMAENAB;
 588		/* autoset shouldn't be set in high bandwidth */
 589		/*
 590		 * Enable Autoset according to table
 591		 * below
 592		 * bulk_split hb_mult	Autoset_Enable
 593		 *	0	1	Yes(Normal)
 594		 *	0	>1	No(High BW ISO)
 595		 *	1	1	Yes(HS bulk)
 596		 *	1	>1	Yes(FS bulk)
 597		 */
 598		if (qh->hb_mult == 1 || (qh->hb_mult > 1 &&
 599					can_bulk_split(hw_ep->musb, qh->type)))
 600			csr |= MUSB_TXCSR_AUTOSET;
 601	} else {
 602		*mode = 0;
 603		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAMODE);
 604		csr |= MUSB_TXCSR_DMAENAB; /* against programmer's guide */
 605	}
 606	channel->desired_mode = *mode;
 607	musb_writew(epio, MUSB_TXCSR, csr);
 608}
 609
 610static void musb_tx_dma_set_mode_cppi_tusb(struct musb_hw_ep *hw_ep,
 611					   struct urb *urb,
 612					   u8 *mode)
 613{
 614	struct dma_channel *channel = hw_ep->tx_channel;
 615
 616	channel->actual_len = 0;
 617
 618	/*
 619	 * TX uses "RNDIS" mode automatically but needs help
 620	 * to identify the zero-length-final-packet case.
 621	 */
 622	*mode = (urb->transfer_flags & URB_ZERO_PACKET) ? 1 : 0;
 623}
 624
 625static bool musb_tx_dma_program(struct dma_controller *dma,
 626		struct musb_hw_ep *hw_ep, struct musb_qh *qh,
 627		struct urb *urb, u32 offset, u32 length)
 628{
 629	struct dma_channel	*channel = hw_ep->tx_channel;
 630	u16			pkt_size = qh->maxpacket;
 631	u8			mode;
 632
 633	if (musb_dma_inventra(hw_ep->musb) || musb_dma_ux500(hw_ep->musb))
 634		musb_tx_dma_set_mode_mentor(hw_ep, qh,
 635					    &length, &mode);
 636	else if (is_cppi_enabled(hw_ep->musb) || tusb_dma_omap(hw_ep->musb))
 637		musb_tx_dma_set_mode_cppi_tusb(hw_ep, urb, &mode);
 638	else
 639		return false;
 640
 641	qh->segsize = length;
 642
 643	/*
 644	 * Ensure the data reaches to main memory before starting
 645	 * DMA transfer
 646	 */
 647	wmb();
 648
 649	if (!dma->channel_program(channel, pkt_size, mode,
 650			urb->transfer_dma + offset, length)) {
 651		void __iomem *epio = hw_ep->regs;
 652		u16 csr;
 653
 654		dma->channel_release(channel);
 655		hw_ep->tx_channel = NULL;
 656
 657		csr = musb_readw(epio, MUSB_TXCSR);
 658		csr &= ~(MUSB_TXCSR_AUTOSET | MUSB_TXCSR_DMAENAB);
 659		musb_writew(epio, MUSB_TXCSR, csr | MUSB_TXCSR_H_WZC_BITS);
 660		return false;
 661	}
 662	return true;
 663}
 664
 665/*
 666 * Program an HDRC endpoint as per the given URB
 667 * Context: irqs blocked, controller lock held
 668 */
 669static void musb_ep_program(struct musb *musb, u8 epnum,
 670			struct urb *urb, int is_out,
 671			u8 *buf, u32 offset, u32 len)
 672{
 673	struct dma_controller	*dma_controller;
 674	struct dma_channel	*dma_channel;
 675	u8			dma_ok;
 676	void __iomem		*mbase = musb->mregs;
 677	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
 678	void __iomem		*epio = hw_ep->regs;
 679	struct musb_qh		*qh = musb_ep_get_qh(hw_ep, !is_out);
 680	u16			packet_sz = qh->maxpacket;
 681	u8			use_dma = 1;
 682	u16			csr;
 683
 684	musb_dbg(musb, "%s hw%d urb %p spd%d dev%d ep%d%s "
 685				"h_addr%02x h_port%02x bytes %d",
 686			is_out ? "-->" : "<--",
 687			epnum, urb, urb->dev->speed,
 688			qh->addr_reg, qh->epnum, is_out ? "out" : "in",
 689			qh->h_addr_reg, qh->h_port_reg,
 690			len);
 691
 692	musb_ep_select(mbase, epnum);
 693
 694	if (is_out && !len) {
 695		use_dma = 0;
 696		csr = musb_readw(epio, MUSB_TXCSR);
 697		csr &= ~MUSB_TXCSR_DMAENAB;
 698		musb_writew(epio, MUSB_TXCSR, csr);
 699		hw_ep->tx_channel = NULL;
 700	}
 701
 702	/* candidate for DMA? */
 703	dma_controller = musb->dma_controller;
 704	if (use_dma && is_dma_capable() && epnum && dma_controller) {
 705		dma_channel = is_out ? hw_ep->tx_channel : hw_ep->rx_channel;
 706		if (!dma_channel) {
 707			dma_channel = dma_controller->channel_alloc(
 708					dma_controller, hw_ep, is_out);
 709			if (is_out)
 710				hw_ep->tx_channel = dma_channel;
 711			else
 712				hw_ep->rx_channel = dma_channel;
 713		}
 714	} else
 715		dma_channel = NULL;
 716
 717	/* make sure we clear DMAEnab, autoSet bits from previous run */
 718
 719	/* OUT/transmit/EP0 or IN/receive? */
 720	if (is_out) {
 721		u16	csr;
 722		u16	int_txe;
 723		u16	load_count;
 724
 725		csr = musb_readw(epio, MUSB_TXCSR);
 726
 727		/* disable interrupt in case we flush */
 728		int_txe = musb->intrtxe;
 729		musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum));
 730
 731		/* general endpoint setup */
 732		if (epnum) {
 733			/* flush all old state, set default */
 734			/*
 735			 * We could be flushing valid
 736			 * packets in double buffering
 737			 * case
 738			 */
 739			if (!hw_ep->tx_double_buffered)
 740				musb_h_tx_flush_fifo(hw_ep);
 741
 742			/*
 743			 * We must not clear the DMAMODE bit before or in
 744			 * the same cycle with the DMAENAB bit, so we clear
 745			 * the latter first...
 746			 */
 747			csr &= ~(MUSB_TXCSR_H_NAKTIMEOUT
 748					| MUSB_TXCSR_AUTOSET
 749					| MUSB_TXCSR_DMAENAB
 750					| MUSB_TXCSR_FRCDATATOG
 751					| MUSB_TXCSR_H_RXSTALL
 752					| MUSB_TXCSR_H_ERROR
 753					| MUSB_TXCSR_TXPKTRDY
 754					);
 755			csr |= MUSB_TXCSR_MODE;
 756
 757			if (!hw_ep->tx_double_buffered)
 758				csr |= musb->io.set_toggle(qh, is_out, urb);
 759
 760			musb_writew(epio, MUSB_TXCSR, csr);
 761			/* REVISIT may need to clear FLUSHFIFO ... */
 762			csr &= ~MUSB_TXCSR_DMAMODE;
 763			musb_writew(epio, MUSB_TXCSR, csr);
 764			csr = musb_readw(epio, MUSB_TXCSR);
 765		} else {
 766			/* endpoint 0: just flush */
 767			musb_h_ep0_flush_fifo(hw_ep);
 768		}
 769
 770		/* target addr and (for multipoint) hub addr/port */
 771		if (musb->is_multipoint) {
 772			musb_write_txfunaddr(musb, epnum, qh->addr_reg);
 773			musb_write_txhubaddr(musb, epnum, qh->h_addr_reg);
 774			musb_write_txhubport(musb, epnum, qh->h_port_reg);
 775/* FIXME if !epnum, do the same for RX ... */
 776		} else
 777			musb_writeb(mbase, MUSB_FADDR, qh->addr_reg);
 778
 779		/* protocol/endpoint/interval/NAKlimit */
 780		if (epnum) {
 781			musb_writeb(epio, MUSB_TXTYPE, qh->type_reg);
 782			if (can_bulk_split(musb, qh->type)) {
 783				qh->hb_mult = hw_ep->max_packet_sz_tx
 784						/ packet_sz;
 785				musb_writew(epio, MUSB_TXMAXP, packet_sz
 786					| ((qh->hb_mult) - 1) << 11);
 787			} else {
 788				musb_writew(epio, MUSB_TXMAXP,
 789						qh->maxpacket |
 790						((qh->hb_mult - 1) << 11));
 791			}
 792			musb_writeb(epio, MUSB_TXINTERVAL, qh->intv_reg);
 793		} else {
 794			musb_writeb(epio, MUSB_NAKLIMIT0, qh->intv_reg);
 795			if (musb->is_multipoint)
 796				musb_writeb(epio, MUSB_TYPE0,
 797						qh->type_reg);
 798		}
 799
 800		if (can_bulk_split(musb, qh->type))
 801			load_count = min_t(u32, hw_ep->max_packet_sz_tx, len);
 
 802		else
 803			load_count = min_t(u32, packet_sz, len);
 804
 805		if (dma_channel && musb_tx_dma_program(dma_controller,
 806					hw_ep, qh, urb, offset, len))
 807			load_count = 0;
 808
 809		if (load_count) {
 810			/* PIO to load FIFO */
 811			qh->segsize = load_count;
 812			if (!buf) {
 813				sg_miter_start(&qh->sg_miter, urb->sg, 1,
 814						SG_MITER_ATOMIC
 815						| SG_MITER_FROM_SG);
 816				if (!sg_miter_next(&qh->sg_miter)) {
 817					dev_err(musb->controller,
 818							"error: sg"
 819							"list empty\n");
 820					sg_miter_stop(&qh->sg_miter);
 821					goto finish;
 822				}
 823				buf = qh->sg_miter.addr + urb->sg->offset +
 824					urb->actual_length;
 825				load_count = min_t(u32, load_count,
 826						qh->sg_miter.length);
 827				musb_write_fifo(hw_ep, load_count, buf);
 828				qh->sg_miter.consumed = load_count;
 829				sg_miter_stop(&qh->sg_miter);
 830			} else
 831				musb_write_fifo(hw_ep, load_count, buf);
 832		}
 833finish:
 834		/* re-enable interrupt */
 835		musb_writew(mbase, MUSB_INTRTXE, int_txe);
 836
 837	/* IN/receive */
 838	} else {
 839		u16 csr = 0;
 840
 841		if (hw_ep->rx_reinit) {
 842			musb_rx_reinit(musb, qh, epnum);
 843			csr |= musb->io.set_toggle(qh, is_out, urb);
 844
 845			if (qh->type == USB_ENDPOINT_XFER_INT)
 846				csr |= MUSB_RXCSR_DISNYET;
 847
 848		} else {
 849			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
 850
 851			if (csr & (MUSB_RXCSR_RXPKTRDY
 852					| MUSB_RXCSR_DMAENAB
 853					| MUSB_RXCSR_H_REQPKT))
 854				ERR("broken !rx_reinit, ep%d csr %04x\n",
 855						hw_ep->epnum, csr);
 856
 857			/* scrub any stale state, leaving toggle alone */
 858			csr &= MUSB_RXCSR_DISNYET;
 859		}
 860
 861		/* kick things off */
 862
 863		if ((is_cppi_enabled(musb) || tusb_dma_omap(musb)) && dma_channel) {
 864			/* Candidate for DMA */
 865			dma_channel->actual_len = 0L;
 866			qh->segsize = len;
 867
 868			/* AUTOREQ is in a DMA register */
 869			musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
 870			csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
 871
 872			/*
 873			 * Unless caller treats short RX transfers as
 874			 * errors, we dare not queue multiple transfers.
 875			 */
 876			dma_ok = dma_controller->channel_program(dma_channel,
 877					packet_sz, !(urb->transfer_flags &
 878						     URB_SHORT_NOT_OK),
 879					urb->transfer_dma + offset,
 880					qh->segsize);
 881			if (!dma_ok) {
 882				dma_controller->channel_release(dma_channel);
 883				hw_ep->rx_channel = dma_channel = NULL;
 884			} else
 885				csr |= MUSB_RXCSR_DMAENAB;
 886		}
 887
 888		csr |= MUSB_RXCSR_H_REQPKT;
 889		musb_dbg(musb, "RXCSR%d := %04x", epnum, csr);
 890		musb_writew(hw_ep->regs, MUSB_RXCSR, csr);
 891		csr = musb_readw(hw_ep->regs, MUSB_RXCSR);
 892	}
 893}
 894
 895/* Schedule next QH from musb->in_bulk/out_bulk and move the current qh to
 896 * the end; avoids starvation for other endpoints.
 897 */
 898static void musb_bulk_nak_timeout(struct musb *musb, struct musb_hw_ep *ep,
 899	int is_in)
 900{
 901	struct dma_channel	*dma;
 902	struct urb		*urb;
 903	void __iomem		*mbase = musb->mregs;
 904	void __iomem		*epio = ep->regs;
 905	struct musb_qh		*cur_qh, *next_qh;
 906	u16			rx_csr, tx_csr;
 907	u16			toggle;
 908
 909	musb_ep_select(mbase, ep->epnum);
 910	if (is_in) {
 911		dma = is_dma_capable() ? ep->rx_channel : NULL;
 912
 913		/*
 914		 * Need to stop the transaction by clearing REQPKT first
 915		 * then the NAK Timeout bit ref MUSBMHDRC USB 2.0 HIGH-SPEED
 916		 * DUAL-ROLE CONTROLLER Programmer's Guide, section 9.2.2
 917		 */
 918		rx_csr = musb_readw(epio, MUSB_RXCSR);
 919		rx_csr |= MUSB_RXCSR_H_WZC_BITS;
 920		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
 921		musb_writew(epio, MUSB_RXCSR, rx_csr);
 922		rx_csr &= ~MUSB_RXCSR_DATAERROR;
 923		musb_writew(epio, MUSB_RXCSR, rx_csr);
 924
 925		cur_qh = first_qh(&musb->in_bulk);
 926	} else {
 927		dma = is_dma_capable() ? ep->tx_channel : NULL;
 928
 929		/* clear nak timeout bit */
 930		tx_csr = musb_readw(epio, MUSB_TXCSR);
 931		tx_csr |= MUSB_TXCSR_H_WZC_BITS;
 932		tx_csr &= ~MUSB_TXCSR_H_NAKTIMEOUT;
 933		musb_writew(epio, MUSB_TXCSR, tx_csr);
 934
 935		cur_qh = first_qh(&musb->out_bulk);
 936	}
 937	if (cur_qh) {
 938		urb = next_urb(cur_qh);
 939		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
 940			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
 941			musb->dma_controller->channel_abort(dma);
 942			urb->actual_length += dma->actual_len;
 943			dma->actual_len = 0L;
 944		}
 945		toggle = musb->io.get_toggle(cur_qh, !is_in);
 946		usb_settoggle(urb->dev, cur_qh->epnum, !is_in, toggle ? 1 : 0);
 947
 948		if (is_in) {
 949			/* move cur_qh to end of queue */
 950			list_move_tail(&cur_qh->ring, &musb->in_bulk);
 951
 952			/* get the next qh from musb->in_bulk */
 953			next_qh = first_qh(&musb->in_bulk);
 954
 955			/* set rx_reinit and schedule the next qh */
 956			ep->rx_reinit = 1;
 957		} else {
 958			/* move cur_qh to end of queue */
 959			list_move_tail(&cur_qh->ring, &musb->out_bulk);
 960
 961			/* get the next qh from musb->out_bulk */
 962			next_qh = first_qh(&musb->out_bulk);
 963
 964			/* set tx_reinit and schedule the next qh */
 965			ep->tx_reinit = 1;
 966		}
 967
 968		if (next_qh)
 969			musb_start_urb(musb, is_in, next_qh);
 970	}
 971}
 972
 973/*
 974 * Service the default endpoint (ep0) as host.
 975 * Return true until it's time to start the status stage.
 976 */
 977static bool musb_h_ep0_continue(struct musb *musb, u16 len, struct urb *urb)
 978{
 979	bool			 more = false;
 980	u8			*fifo_dest = NULL;
 981	u16			fifo_count = 0;
 982	struct musb_hw_ep	*hw_ep = musb->control_ep;
 983	struct musb_qh		*qh = hw_ep->in_qh;
 984	struct usb_ctrlrequest	*request;
 985
 986	switch (musb->ep0_stage) {
 987	case MUSB_EP0_IN:
 988		fifo_dest = urb->transfer_buffer + urb->actual_length;
 989		fifo_count = min_t(size_t, len, urb->transfer_buffer_length -
 990				   urb->actual_length);
 991		if (fifo_count < len)
 992			urb->status = -EOVERFLOW;
 993
 994		musb_read_fifo(hw_ep, fifo_count, fifo_dest);
 995
 996		urb->actual_length += fifo_count;
 997		if (len < qh->maxpacket) {
 998			/* always terminate on short read; it's
 999			 * rarely reported as an error.
1000			 */
1001		} else if (urb->actual_length <
1002				urb->transfer_buffer_length)
1003			more = true;
1004		break;
1005	case MUSB_EP0_START:
1006		request = (struct usb_ctrlrequest *) urb->setup_packet;
1007
1008		if (!request->wLength) {
1009			musb_dbg(musb, "start no-DATA");
1010			break;
1011		} else if (request->bRequestType & USB_DIR_IN) {
1012			musb_dbg(musb, "start IN-DATA");
1013			musb->ep0_stage = MUSB_EP0_IN;
1014			more = true;
1015			break;
1016		} else {
1017			musb_dbg(musb, "start OUT-DATA");
1018			musb->ep0_stage = MUSB_EP0_OUT;
1019			more = true;
1020		}
1021		fallthrough;
1022	case MUSB_EP0_OUT:
1023		fifo_count = min_t(size_t, qh->maxpacket,
1024				   urb->transfer_buffer_length -
1025				   urb->actual_length);
1026		if (fifo_count) {
1027			fifo_dest = (u8 *) (urb->transfer_buffer
1028					+ urb->actual_length);
1029			musb_dbg(musb, "Sending %d byte%s to ep0 fifo %p",
1030					fifo_count,
1031					(fifo_count == 1) ? "" : "s",
1032					fifo_dest);
1033			musb_write_fifo(hw_ep, fifo_count, fifo_dest);
1034
1035			urb->actual_length += fifo_count;
1036			more = true;
1037		}
1038		break;
1039	default:
1040		ERR("bogus ep0 stage %d\n", musb->ep0_stage);
1041		break;
1042	}
1043
1044	return more;
1045}
1046
1047/*
1048 * Handle default endpoint interrupt as host. Only called in IRQ time
1049 * from musb_interrupt().
1050 *
1051 * called with controller irqlocked
1052 */
1053irqreturn_t musb_h_ep0_irq(struct musb *musb)
1054{
1055	struct urb		*urb;
1056	u16			csr, len;
1057	int			status = 0;
1058	void __iomem		*mbase = musb->mregs;
1059	struct musb_hw_ep	*hw_ep = musb->control_ep;
1060	void __iomem		*epio = hw_ep->regs;
1061	struct musb_qh		*qh = hw_ep->in_qh;
1062	bool			complete = false;
1063	irqreturn_t		retval = IRQ_NONE;
1064
1065	/* ep0 only has one queue, "in" */
1066	urb = next_urb(qh);
1067
1068	musb_ep_select(mbase, 0);
1069	csr = musb_readw(epio, MUSB_CSR0);
1070	len = (csr & MUSB_CSR0_RXPKTRDY)
1071			? musb_readb(epio, MUSB_COUNT0)
1072			: 0;
1073
1074	musb_dbg(musb, "<== csr0 %04x, qh %p, count %d, urb %p, stage %d",
1075		csr, qh, len, urb, musb->ep0_stage);
1076
1077	/* if we just did status stage, we are done */
1078	if (MUSB_EP0_STATUS == musb->ep0_stage) {
1079		retval = IRQ_HANDLED;
1080		complete = true;
1081	}
1082
1083	/* prepare status */
1084	if (csr & MUSB_CSR0_H_RXSTALL) {
1085		musb_dbg(musb, "STALLING ENDPOINT");
1086		status = -EPIPE;
1087
1088	} else if (csr & MUSB_CSR0_H_ERROR) {
1089		musb_dbg(musb, "no response, csr0 %04x", csr);
1090		status = -EPROTO;
1091
1092	} else if (csr & MUSB_CSR0_H_NAKTIMEOUT) {
1093		musb_dbg(musb, "control NAK timeout");
1094
1095		/* NOTE:  this code path would be a good place to PAUSE a
1096		 * control transfer, if another one is queued, so that
1097		 * ep0 is more likely to stay busy.  That's already done
1098		 * for bulk RX transfers.
1099		 *
1100		 * if (qh->ring.next != &musb->control), then
1101		 * we have a candidate... NAKing is *NOT* an error
1102		 */
1103		musb_writew(epio, MUSB_CSR0, 0);
1104		retval = IRQ_HANDLED;
1105	}
1106
1107	if (status) {
1108		musb_dbg(musb, "aborting");
1109		retval = IRQ_HANDLED;
1110		if (urb)
1111			urb->status = status;
1112		complete = true;
1113
1114		/* use the proper sequence to abort the transfer */
1115		if (csr & MUSB_CSR0_H_REQPKT) {
1116			csr &= ~MUSB_CSR0_H_REQPKT;
1117			musb_writew(epio, MUSB_CSR0, csr);
1118			csr &= ~MUSB_CSR0_H_NAKTIMEOUT;
1119			musb_writew(epio, MUSB_CSR0, csr);
1120		} else {
1121			musb_h_ep0_flush_fifo(hw_ep);
1122		}
1123
1124		musb_writeb(epio, MUSB_NAKLIMIT0, 0);
1125
1126		/* clear it */
1127		musb_writew(epio, MUSB_CSR0, 0);
1128	}
1129
1130	if (unlikely(!urb)) {
1131		/* stop endpoint since we have no place for its data, this
1132		 * SHOULD NEVER HAPPEN! */
1133		ERR("no URB for end 0\n");
1134
1135		musb_h_ep0_flush_fifo(hw_ep);
1136		goto done;
1137	}
1138
1139	if (!complete) {
1140		/* call common logic and prepare response */
1141		if (musb_h_ep0_continue(musb, len, urb)) {
1142			/* more packets required */
1143			csr = (MUSB_EP0_IN == musb->ep0_stage)
1144				?  MUSB_CSR0_H_REQPKT : MUSB_CSR0_TXPKTRDY;
1145		} else {
1146			/* data transfer complete; perform status phase */
1147			if (usb_pipeout(urb->pipe)
1148					|| !urb->transfer_buffer_length)
1149				csr = MUSB_CSR0_H_STATUSPKT
1150					| MUSB_CSR0_H_REQPKT;
1151			else
1152				csr = MUSB_CSR0_H_STATUSPKT
1153					| MUSB_CSR0_TXPKTRDY;
1154
1155			/* disable ping token in status phase */
1156			csr |= MUSB_CSR0_H_DIS_PING;
1157
1158			/* flag status stage */
1159			musb->ep0_stage = MUSB_EP0_STATUS;
1160
1161			musb_dbg(musb, "ep0 STATUS, csr %04x", csr);
1162
1163		}
1164		musb_writew(epio, MUSB_CSR0, csr);
1165		retval = IRQ_HANDLED;
1166	} else
1167		musb->ep0_stage = MUSB_EP0_IDLE;
1168
1169	/* call completion handler if done */
1170	if (complete)
1171		musb_advance_schedule(musb, urb, hw_ep, 1);
1172done:
1173	return retval;
1174}
1175
1176
1177#ifdef CONFIG_USB_INVENTRA_DMA
1178
1179/* Host side TX (OUT) using Mentor DMA works as follows:
1180	submit_urb ->
1181		- if queue was empty, Program Endpoint
1182		- ... which starts DMA to fifo in mode 1 or 0
1183
1184	DMA Isr (transfer complete) -> TxAvail()
1185		- Stop DMA (~DmaEnab)	(<--- Alert ... currently happens
1186					only in musb_cleanup_urb)
1187		- TxPktRdy has to be set in mode 0 or for
1188			short packets in mode 1.
1189*/
1190
1191#endif
1192
1193/* Service a Tx-Available or dma completion irq for the endpoint */
1194void musb_host_tx(struct musb *musb, u8 epnum)
1195{
1196	int			pipe;
1197	bool			done = false;
1198	u16			tx_csr;
1199	size_t			length = 0;
1200	size_t			offset = 0;
1201	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1202	void __iomem		*epio = hw_ep->regs;
1203	struct musb_qh		*qh = hw_ep->out_qh;
1204	struct urb		*urb = next_urb(qh);
1205	u32			status = 0;
1206	void __iomem		*mbase = musb->mregs;
1207	struct dma_channel	*dma;
1208	bool			transfer_pending = false;
1209
1210	musb_ep_select(mbase, epnum);
1211	tx_csr = musb_readw(epio, MUSB_TXCSR);
1212
1213	/* with CPPI, DMA sometimes triggers "extra" irqs */
1214	if (!urb) {
1215		musb_dbg(musb, "extra TX%d ready, csr %04x", epnum, tx_csr);
1216		return;
1217	}
1218
1219	pipe = urb->pipe;
1220	dma = is_dma_capable() ? hw_ep->tx_channel : NULL;
1221	trace_musb_urb_tx(musb, urb);
1222	musb_dbg(musb, "OUT/TX%d end, csr %04x%s", epnum, tx_csr,
1223			dma ? ", dma" : "");
1224
1225	/* check for errors */
1226	if (tx_csr & MUSB_TXCSR_H_RXSTALL) {
1227		/* dma was disabled, fifo flushed */
1228		musb_dbg(musb, "TX end %d stall", epnum);
1229
1230		/* stall; record URB status */
1231		status = -EPIPE;
1232
1233	} else if (tx_csr & MUSB_TXCSR_H_ERROR) {
1234		/* (NON-ISO) dma was disabled, fifo flushed */
1235		musb_dbg(musb, "TX 3strikes on ep=%d", epnum);
1236
1237		status = -ETIMEDOUT;
1238
1239	} else if (tx_csr & MUSB_TXCSR_H_NAKTIMEOUT) {
1240		if (USB_ENDPOINT_XFER_BULK == qh->type && qh->mux == 1
1241				&& !list_is_singular(&musb->out_bulk)) {
1242			musb_dbg(musb, "NAK timeout on TX%d ep", epnum);
1243			musb_bulk_nak_timeout(musb, hw_ep, 0);
1244		} else {
1245			musb_dbg(musb, "TX ep%d device not responding", epnum);
1246			/* NOTE:  this code path would be a good place to PAUSE a
1247			 * transfer, if there's some other (nonperiodic) tx urb
1248			 * that could use this fifo.  (dma complicates it...)
1249			 * That's already done for bulk RX transfers.
1250			 *
1251			 * if (bulk && qh->ring.next != &musb->out_bulk), then
1252			 * we have a candidate... NAKing is *NOT* an error
1253			 */
1254			musb_ep_select(mbase, epnum);
1255			musb_writew(epio, MUSB_TXCSR,
1256					MUSB_TXCSR_H_WZC_BITS
1257					| MUSB_TXCSR_TXPKTRDY);
1258		}
1259		return;
1260	}
1261
1262done:
1263	if (status) {
1264		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1265			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1266			musb->dma_controller->channel_abort(dma);
1267		}
1268
1269		/* do the proper sequence to abort the transfer in the
1270		 * usb core; the dma engine should already be stopped.
1271		 */
1272		musb_h_tx_flush_fifo(hw_ep);
1273		tx_csr &= ~(MUSB_TXCSR_AUTOSET
1274				| MUSB_TXCSR_DMAENAB
1275				| MUSB_TXCSR_H_ERROR
1276				| MUSB_TXCSR_H_RXSTALL
1277				| MUSB_TXCSR_H_NAKTIMEOUT
1278				);
1279
1280		musb_ep_select(mbase, epnum);
1281		musb_writew(epio, MUSB_TXCSR, tx_csr);
1282		/* REVISIT may need to clear FLUSHFIFO ... */
1283		musb_writew(epio, MUSB_TXCSR, tx_csr);
1284		musb_writeb(epio, MUSB_TXINTERVAL, 0);
1285
1286		done = true;
1287	}
1288
1289	/* second cppi case */
1290	if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1291		musb_dbg(musb, "extra TX%d ready, csr %04x", epnum, tx_csr);
1292		return;
1293	}
1294
1295	if (is_dma_capable() && dma && !status) {
1296		/*
1297		 * DMA has completed.  But if we're using DMA mode 1 (multi
1298		 * packet DMA), we need a terminal TXPKTRDY interrupt before
1299		 * we can consider this transfer completed, lest we trash
1300		 * its last packet when writing the next URB's data.  So we
1301		 * switch back to mode 0 to get that interrupt; we'll come
1302		 * back here once it happens.
1303		 */
1304		if (tx_csr & MUSB_TXCSR_DMAMODE) {
1305			/*
1306			 * We shouldn't clear DMAMODE with DMAENAB set; so
1307			 * clear them in a safe order.  That should be OK
1308			 * once TXPKTRDY has been set (and I've never seen
1309			 * it being 0 at this moment -- DMA interrupt latency
1310			 * is significant) but if it hasn't been then we have
1311			 * no choice but to stop being polite and ignore the
1312			 * programmer's guide... :-)
1313			 *
1314			 * Note that we must write TXCSR with TXPKTRDY cleared
1315			 * in order not to re-trigger the packet send (this bit
1316			 * can't be cleared by CPU), and there's another caveat:
1317			 * TXPKTRDY may be set shortly and then cleared in the
1318			 * double-buffered FIFO mode, so we do an extra TXCSR
1319			 * read for debouncing...
1320			 */
1321			tx_csr &= musb_readw(epio, MUSB_TXCSR);
1322			if (tx_csr & MUSB_TXCSR_TXPKTRDY) {
1323				tx_csr &= ~(MUSB_TXCSR_DMAENAB |
1324					    MUSB_TXCSR_TXPKTRDY);
1325				musb_writew(epio, MUSB_TXCSR,
1326					    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1327			}
1328			tx_csr &= ~(MUSB_TXCSR_DMAMODE |
1329				    MUSB_TXCSR_TXPKTRDY);
1330			musb_writew(epio, MUSB_TXCSR,
1331				    tx_csr | MUSB_TXCSR_H_WZC_BITS);
1332
1333			/*
1334			 * There is no guarantee that we'll get an interrupt
1335			 * after clearing DMAMODE as we might have done this
1336			 * too late (after TXPKTRDY was cleared by controller).
1337			 * Re-read TXCSR as we have spoiled its previous value.
1338			 */
1339			tx_csr = musb_readw(epio, MUSB_TXCSR);
1340		}
1341
1342		/*
1343		 * We may get here from a DMA completion or TXPKTRDY interrupt.
1344		 * In any case, we must check the FIFO status here and bail out
1345		 * only if the FIFO still has data -- that should prevent the
1346		 * "missed" TXPKTRDY interrupts and deal with double-buffered
1347		 * FIFO mode too...
1348		 */
1349		if (tx_csr & (MUSB_TXCSR_FIFONOTEMPTY | MUSB_TXCSR_TXPKTRDY)) {
1350			musb_dbg(musb,
1351				"DMA complete but FIFO not empty, CSR %04x",
1352				tx_csr);
1353			return;
1354		}
1355	}
1356
1357	if (!status || dma || usb_pipeisoc(pipe)) {
1358		if (dma)
1359			length = dma->actual_len;
1360		else
1361			length = qh->segsize;
1362		qh->offset += length;
1363
1364		if (usb_pipeisoc(pipe)) {
1365			struct usb_iso_packet_descriptor	*d;
1366
1367			d = urb->iso_frame_desc + qh->iso_idx;
1368			d->actual_length = length;
1369			d->status = status;
1370			if (++qh->iso_idx >= urb->number_of_packets) {
1371				done = true;
1372			} else {
1373				d++;
1374				offset = d->offset;
1375				length = d->length;
1376			}
1377		} else if (dma && urb->transfer_buffer_length == qh->offset) {
1378			done = true;
1379		} else {
1380			/* see if we need to send more data, or ZLP */
1381			if (qh->segsize < qh->maxpacket)
1382				done = true;
1383			else if (qh->offset == urb->transfer_buffer_length
1384					&& !(urb->transfer_flags
1385						& URB_ZERO_PACKET))
1386				done = true;
1387			if (!done) {
1388				offset = qh->offset;
1389				length = urb->transfer_buffer_length - offset;
1390				transfer_pending = true;
1391			}
1392		}
1393	}
1394
1395	/* urb->status != -EINPROGRESS means request has been faulted,
1396	 * so we must abort this transfer after cleanup
1397	 */
1398	if (urb->status != -EINPROGRESS) {
1399		done = true;
1400		if (status == 0)
1401			status = urb->status;
1402	}
1403
1404	if (done) {
1405		/* set status */
1406		urb->status = status;
1407		urb->actual_length = qh->offset;
1408		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_OUT);
1409		return;
1410	} else if ((usb_pipeisoc(pipe) || transfer_pending) && dma) {
1411		if (musb_tx_dma_program(musb->dma_controller, hw_ep, qh, urb,
1412				offset, length)) {
1413			if (is_cppi_enabled(musb) || tusb_dma_omap(musb))
1414				musb_h_tx_dma_start(hw_ep);
1415			return;
1416		}
1417	} else	if (tx_csr & MUSB_TXCSR_DMAENAB) {
1418		musb_dbg(musb, "not complete, but DMA enabled?");
1419		return;
1420	}
1421
1422	/*
1423	 * PIO: start next packet in this URB.
1424	 *
1425	 * REVISIT: some docs say that when hw_ep->tx_double_buffered,
1426	 * (and presumably, FIFO is not half-full) we should write *two*
1427	 * packets before updating TXCSR; other docs disagree...
1428	 */
1429	if (length > qh->maxpacket)
1430		length = qh->maxpacket;
1431	/* Unmap the buffer so that CPU can use it */
1432	usb_hcd_unmap_urb_for_dma(musb->hcd, urb);
1433
1434	/*
1435	 * We need to map sg if the transfer_buffer is
1436	 * NULL.
1437	 */
1438	if (!urb->transfer_buffer) {
1439		/* sg_miter_start is already done in musb_ep_program */
1440		if (!sg_miter_next(&qh->sg_miter)) {
1441			dev_err(musb->controller, "error: sg list empty\n");
1442			sg_miter_stop(&qh->sg_miter);
1443			status = -EINVAL;
1444			goto done;
1445		}
1446		length = min_t(u32, length, qh->sg_miter.length);
1447		musb_write_fifo(hw_ep, length, qh->sg_miter.addr);
1448		qh->sg_miter.consumed = length;
1449		sg_miter_stop(&qh->sg_miter);
1450	} else {
1451		musb_write_fifo(hw_ep, length, urb->transfer_buffer + offset);
1452	}
1453
1454	qh->segsize = length;
1455
1456	musb_ep_select(mbase, epnum);
1457	musb_writew(epio, MUSB_TXCSR,
1458			MUSB_TXCSR_H_WZC_BITS | MUSB_TXCSR_TXPKTRDY);
1459}
1460
1461#ifdef CONFIG_USB_TI_CPPI41_DMA
1462/* Seems to set up ISO for cppi41 and not advance len. See commit c57c41d */
1463static int musb_rx_dma_iso_cppi41(struct dma_controller *dma,
1464				  struct musb_hw_ep *hw_ep,
1465				  struct musb_qh *qh,
1466				  struct urb *urb,
1467				  size_t len)
1468{
1469	struct dma_channel *channel = hw_ep->rx_channel;
1470	void __iomem *epio = hw_ep->regs;
1471	dma_addr_t *buf;
1472	u32 length;
1473	u16 val;
1474
1475	buf = (void *)urb->iso_frame_desc[qh->iso_idx].offset +
1476		(u32)urb->transfer_dma;
1477
1478	length = urb->iso_frame_desc[qh->iso_idx].length;
1479
1480	val = musb_readw(epio, MUSB_RXCSR);
1481	val |= MUSB_RXCSR_DMAENAB;
1482	musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1483
1484	return dma->channel_program(channel, qh->maxpacket, 0,
1485				   (u32)buf, length);
1486}
1487#else
1488static inline int musb_rx_dma_iso_cppi41(struct dma_controller *dma,
1489					 struct musb_hw_ep *hw_ep,
1490					 struct musb_qh *qh,
1491					 struct urb *urb,
1492					 size_t len)
1493{
1494	return false;
1495}
1496#endif
1497
1498#if defined(CONFIG_USB_INVENTRA_DMA) || defined(CONFIG_USB_UX500_DMA) || \
1499	defined(CONFIG_USB_TI_CPPI41_DMA)
1500/* Host side RX (IN) using Mentor DMA works as follows:
1501	submit_urb ->
1502		- if queue was empty, ProgramEndpoint
1503		- first IN token is sent out (by setting ReqPkt)
1504	LinuxIsr -> RxReady()
1505	/\	=> first packet is received
1506	|	- Set in mode 0 (DmaEnab, ~ReqPkt)
1507	|		-> DMA Isr (transfer complete) -> RxReady()
1508	|		    - Ack receive (~RxPktRdy), turn off DMA (~DmaEnab)
1509	|		    - if urb not complete, send next IN token (ReqPkt)
1510	|			   |		else complete urb.
1511	|			   |
1512	---------------------------
1513 *
1514 * Nuances of mode 1:
1515 *	For short packets, no ack (+RxPktRdy) is sent automatically
1516 *	(even if AutoClear is ON)
1517 *	For full packets, ack (~RxPktRdy) and next IN token (+ReqPkt) is sent
1518 *	automatically => major problem, as collecting the next packet becomes
1519 *	difficult. Hence mode 1 is not used.
1520 *
1521 * REVISIT
1522 *	All we care about at this driver level is that
1523 *       (a) all URBs terminate with REQPKT cleared and fifo(s) empty;
1524 *       (b) termination conditions are: short RX, or buffer full;
1525 *       (c) fault modes include
1526 *           - iff URB_SHORT_NOT_OK, short RX status is -EREMOTEIO.
1527 *             (and that endpoint's dma queue stops immediately)
1528 *           - overflow (full, PLUS more bytes in the terminal packet)
1529 *
1530 *	So for example, usb-storage sets URB_SHORT_NOT_OK, and would
1531 *	thus be a great candidate for using mode 1 ... for all but the
1532 *	last packet of one URB's transfer.
1533 */
1534static int musb_rx_dma_inventra_cppi41(struct dma_controller *dma,
1535				       struct musb_hw_ep *hw_ep,
1536				       struct musb_qh *qh,
1537				       struct urb *urb,
1538				       size_t len)
1539{
1540	struct dma_channel *channel = hw_ep->rx_channel;
1541	void __iomem *epio = hw_ep->regs;
1542	u16 val;
1543	int pipe;
1544	bool done;
1545
1546	pipe = urb->pipe;
1547
1548	if (usb_pipeisoc(pipe)) {
1549		struct usb_iso_packet_descriptor *d;
1550
1551		d = urb->iso_frame_desc + qh->iso_idx;
1552		d->actual_length = len;
1553
1554		/* even if there was an error, we did the dma
1555		 * for iso_frame_desc->length
1556		 */
1557		if (d->status != -EILSEQ && d->status != -EOVERFLOW)
1558			d->status = 0;
1559
1560		if (++qh->iso_idx >= urb->number_of_packets) {
1561			done = true;
1562		} else {
1563			/* REVISIT: Why ignore return value here? */
1564			if (musb_dma_cppi41(hw_ep->musb))
1565				done = musb_rx_dma_iso_cppi41(dma, hw_ep, qh,
1566							      urb, len);
1567			done = false;
1568		}
1569
1570	} else  {
1571		/* done if urb buffer is full or short packet is recd */
1572		done = (urb->actual_length + len >=
1573			urb->transfer_buffer_length
1574			|| channel->actual_len < qh->maxpacket
1575			|| channel->rx_packet_done);
1576	}
1577
1578	/* send IN token for next packet, without AUTOREQ */
1579	if (!done) {
1580		val = musb_readw(epio, MUSB_RXCSR);
1581		val |= MUSB_RXCSR_H_REQPKT;
1582		musb_writew(epio, MUSB_RXCSR, MUSB_RXCSR_H_WZC_BITS | val);
1583	}
1584
1585	return done;
1586}
1587
1588/* Disadvantage of using mode 1:
1589 *	It's basically usable only for mass storage class; essentially all
1590 *	other protocols also terminate transfers on short packets.
1591 *
1592 * Details:
1593 *	An extra IN token is sent at the end of the transfer (due to AUTOREQ)
1594 *	If you try to use mode 1 for (transfer_buffer_length - 512), and try
1595 *	to use the extra IN token to grab the last packet using mode 0, then
1596 *	the problem is that you cannot be sure when the device will send the
1597 *	last packet and RxPktRdy set. Sometimes the packet is recd too soon
1598 *	such that it gets lost when RxCSR is re-set at the end of the mode 1
1599 *	transfer, while sometimes it is recd just a little late so that if you
1600 *	try to configure for mode 0 soon after the mode 1 transfer is
1601 *	completed, you will find rxcount 0. Okay, so you might think why not
1602 *	wait for an interrupt when the pkt is recd. Well, you won't get any!
1603 */
1604static int musb_rx_dma_in_inventra_cppi41(struct dma_controller *dma,
1605					  struct musb_hw_ep *hw_ep,
1606					  struct musb_qh *qh,
1607					  struct urb *urb,
1608					  size_t len,
1609					  u8 iso_err)
1610{
1611	struct musb *musb = hw_ep->musb;
1612	void __iomem *epio = hw_ep->regs;
1613	struct dma_channel *channel = hw_ep->rx_channel;
1614	u16 rx_count, val;
1615	int length, pipe, done;
1616	dma_addr_t buf;
1617
1618	rx_count = musb_readw(epio, MUSB_RXCOUNT);
1619	pipe = urb->pipe;
1620
1621	if (usb_pipeisoc(pipe)) {
1622		int d_status = 0;
1623		struct usb_iso_packet_descriptor *d;
1624
1625		d = urb->iso_frame_desc + qh->iso_idx;
1626
1627		if (iso_err) {
1628			d_status = -EILSEQ;
1629			urb->error_count++;
1630		}
1631		if (rx_count > d->length) {
1632			if (d_status == 0) {
1633				d_status = -EOVERFLOW;
1634				urb->error_count++;
1635			}
1636			musb_dbg(musb, "** OVERFLOW %d into %d",
1637				rx_count, d->length);
1638
1639			length = d->length;
1640		} else
1641			length = rx_count;
1642		d->status = d_status;
1643		buf = urb->transfer_dma + d->offset;
1644	} else {
1645		length = rx_count;
1646		buf = urb->transfer_dma + urb->actual_length;
1647	}
1648
1649	channel->desired_mode = 0;
1650#ifdef USE_MODE1
1651	/* because of the issue below, mode 1 will
1652	 * only rarely behave with correct semantics.
1653	 */
1654	if ((urb->transfer_flags & URB_SHORT_NOT_OK)
1655	    && (urb->transfer_buffer_length - urb->actual_length)
1656	    > qh->maxpacket)
1657		channel->desired_mode = 1;
1658	if (rx_count < hw_ep->max_packet_sz_rx) {
1659		length = rx_count;
1660		channel->desired_mode = 0;
1661	} else {
1662		length = urb->transfer_buffer_length;
1663	}
1664#endif
1665
1666	/* See comments above on disadvantages of using mode 1 */
1667	val = musb_readw(epio, MUSB_RXCSR);
1668	val &= ~MUSB_RXCSR_H_REQPKT;
1669
1670	if (channel->desired_mode == 0)
1671		val &= ~MUSB_RXCSR_H_AUTOREQ;
1672	else
1673		val |= MUSB_RXCSR_H_AUTOREQ;
1674	val |= MUSB_RXCSR_DMAENAB;
1675
1676	/* autoclear shouldn't be set in high bandwidth */
1677	if (qh->hb_mult == 1)
1678		val |= MUSB_RXCSR_AUTOCLEAR;
1679
1680	musb_writew(epio, MUSB_RXCSR, MUSB_RXCSR_H_WZC_BITS | val);
1681
1682	/* REVISIT if when actual_length != 0,
1683	 * transfer_buffer_length needs to be
1684	 * adjusted first...
1685	 */
1686	done = dma->channel_program(channel, qh->maxpacket,
1687				   channel->desired_mode,
1688				   buf, length);
1689
1690	if (!done) {
1691		dma->channel_release(channel);
1692		hw_ep->rx_channel = NULL;
1693		channel = NULL;
1694		val = musb_readw(epio, MUSB_RXCSR);
1695		val &= ~(MUSB_RXCSR_DMAENAB
1696			 | MUSB_RXCSR_H_AUTOREQ
1697			 | MUSB_RXCSR_AUTOCLEAR);
1698		musb_writew(epio, MUSB_RXCSR, val);
1699	}
1700
1701	return done;
1702}
1703#else
1704static inline int musb_rx_dma_inventra_cppi41(struct dma_controller *dma,
1705					      struct musb_hw_ep *hw_ep,
1706					      struct musb_qh *qh,
1707					      struct urb *urb,
1708					      size_t len)
1709{
1710	return false;
1711}
1712
1713static inline int musb_rx_dma_in_inventra_cppi41(struct dma_controller *dma,
1714						 struct musb_hw_ep *hw_ep,
1715						 struct musb_qh *qh,
1716						 struct urb *urb,
1717						 size_t len,
1718						 u8 iso_err)
1719{
1720	return false;
1721}
1722#endif
1723
1724/*
1725 * Service an RX interrupt for the given IN endpoint; docs cover bulk, iso,
1726 * and high-bandwidth IN transfer cases.
1727 */
1728void musb_host_rx(struct musb *musb, u8 epnum)
1729{
1730	struct urb		*urb;
1731	struct musb_hw_ep	*hw_ep = musb->endpoints + epnum;
1732	struct dma_controller	*c = musb->dma_controller;
1733	void __iomem		*epio = hw_ep->regs;
1734	struct musb_qh		*qh = hw_ep->in_qh;
1735	size_t			xfer_len;
1736	void __iomem		*mbase = musb->mregs;
1737	u16			rx_csr, val;
1738	bool			iso_err = false;
1739	bool			done = false;
1740	u32			status;
1741	struct dma_channel	*dma;
1742	unsigned int sg_flags = SG_MITER_ATOMIC | SG_MITER_TO_SG;
1743
1744	musb_ep_select(mbase, epnum);
1745
1746	urb = next_urb(qh);
1747	dma = is_dma_capable() ? hw_ep->rx_channel : NULL;
1748	status = 0;
1749	xfer_len = 0;
1750
1751	rx_csr = musb_readw(epio, MUSB_RXCSR);
1752	val = rx_csr;
1753
1754	if (unlikely(!urb)) {
1755		/* REVISIT -- THIS SHOULD NEVER HAPPEN ... but, at least
1756		 * usbtest #11 (unlinks) triggers it regularly, sometimes
1757		 * with fifo full.  (Only with DMA??)
1758		 */
1759		musb_dbg(musb, "BOGUS RX%d ready, csr %04x, count %d",
1760			epnum, val, musb_readw(epio, MUSB_RXCOUNT));
1761		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1762		return;
1763	}
1764
1765	trace_musb_urb_rx(musb, urb);
1766
1767	/* check for errors, concurrent stall & unlink is not really
1768	 * handled yet! */
1769	if (rx_csr & MUSB_RXCSR_H_RXSTALL) {
1770		musb_dbg(musb, "RX end %d STALL", epnum);
1771
1772		/* stall; record URB status */
1773		status = -EPIPE;
1774
1775	} else if (rx_csr & MUSB_RXCSR_H_ERROR) {
1776		dev_err(musb->controller, "ep%d RX three-strikes error", epnum);
1777
1778		/*
1779		 * The three-strikes error could only happen when the USB
1780		 * device is not accessible, for example detached or powered
1781		 * off. So return the fatal error -ESHUTDOWN so hopefully the
1782		 * USB device drivers won't immediately resubmit the same URB.
1783		 */
1784		status = -ESHUTDOWN;
1785		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1786
1787		rx_csr &= ~MUSB_RXCSR_H_ERROR;
1788		musb_writew(epio, MUSB_RXCSR, rx_csr);
1789
1790	} else if (rx_csr & MUSB_RXCSR_DATAERROR) {
1791
1792		if (USB_ENDPOINT_XFER_ISOC != qh->type) {
1793			musb_dbg(musb, "RX end %d NAK timeout", epnum);
1794
1795			/* NOTE: NAKing is *NOT* an error, so we want to
1796			 * continue.  Except ... if there's a request for
1797			 * another QH, use that instead of starving it.
1798			 *
1799			 * Devices like Ethernet and serial adapters keep
1800			 * reads posted at all times, which will starve
1801			 * other devices without this logic.
1802			 */
1803			if (usb_pipebulk(urb->pipe)
1804					&& qh->mux == 1
1805					&& !list_is_singular(&musb->in_bulk)) {
1806				musb_bulk_nak_timeout(musb, hw_ep, 1);
1807				return;
1808			}
1809			musb_ep_select(mbase, epnum);
1810			rx_csr |= MUSB_RXCSR_H_WZC_BITS;
1811			rx_csr &= ~MUSB_RXCSR_DATAERROR;
1812			musb_writew(epio, MUSB_RXCSR, rx_csr);
1813
1814			goto finish;
1815		} else {
1816			musb_dbg(musb, "RX end %d ISO data error", epnum);
1817			/* packet error reported later */
1818			iso_err = true;
1819		}
1820	} else if (rx_csr & MUSB_RXCSR_INCOMPRX) {
1821		musb_dbg(musb, "end %d high bandwidth incomplete ISO packet RX",
1822				epnum);
1823		status = -EPROTO;
1824	}
1825
1826	/* faults abort the transfer */
1827	if (status) {
1828		/* clean up dma and collect transfer count */
1829		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1830			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1831			musb->dma_controller->channel_abort(dma);
1832			xfer_len = dma->actual_len;
1833		}
1834		musb_h_flush_rxfifo(hw_ep, MUSB_RXCSR_CLRDATATOG);
1835		musb_writeb(epio, MUSB_RXINTERVAL, 0);
1836		done = true;
1837		goto finish;
1838	}
1839
1840	if (unlikely(dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY)) {
1841		/* SHOULD NEVER HAPPEN ... but at least DaVinci has done it */
1842		ERR("RX%d dma busy, csr %04x\n", epnum, rx_csr);
1843		goto finish;
1844	}
1845
1846	/* thorough shutdown for now ... given more precise fault handling
1847	 * and better queueing support, we might keep a DMA pipeline going
1848	 * while processing this irq for earlier completions.
1849	 */
1850
1851	/* FIXME this is _way_ too much in-line logic for Mentor DMA */
1852	if (!musb_dma_inventra(musb) && !musb_dma_ux500(musb) &&
1853	    (rx_csr & MUSB_RXCSR_H_REQPKT)) {
1854		/* REVISIT this happened for a while on some short reads...
1855		 * the cleanup still needs investigation... looks bad...
1856		 * and also duplicates dma cleanup code above ... plus,
1857		 * shouldn't this be the "half full" double buffer case?
1858		 */
1859		if (dma_channel_status(dma) == MUSB_DMA_STATUS_BUSY) {
1860			dma->status = MUSB_DMA_STATUS_CORE_ABORT;
1861			musb->dma_controller->channel_abort(dma);
1862			xfer_len = dma->actual_len;
1863			done = true;
1864		}
1865
1866		musb_dbg(musb, "RXCSR%d %04x, reqpkt, len %zu%s", epnum, rx_csr,
1867				xfer_len, dma ? ", dma" : "");
1868		rx_csr &= ~MUSB_RXCSR_H_REQPKT;
1869
1870		musb_ep_select(mbase, epnum);
1871		musb_writew(epio, MUSB_RXCSR,
1872				MUSB_RXCSR_H_WZC_BITS | rx_csr);
1873	}
1874
1875	if (dma && (rx_csr & MUSB_RXCSR_DMAENAB)) {
1876		xfer_len = dma->actual_len;
1877
1878		val &= ~(MUSB_RXCSR_DMAENAB
1879			| MUSB_RXCSR_H_AUTOREQ
1880			| MUSB_RXCSR_AUTOCLEAR
1881			| MUSB_RXCSR_RXPKTRDY);
1882		musb_writew(hw_ep->regs, MUSB_RXCSR, val);
1883
1884		if (musb_dma_inventra(musb) || musb_dma_ux500(musb) ||
1885		    musb_dma_cppi41(musb)) {
1886			    done = musb_rx_dma_inventra_cppi41(c, hw_ep, qh, urb, xfer_len);
1887			    musb_dbg(hw_ep->musb,
1888				    "ep %d dma %s, rxcsr %04x, rxcount %d",
1889				    epnum, done ? "off" : "reset",
1890				    musb_readw(epio, MUSB_RXCSR),
1891				    musb_readw(epio, MUSB_RXCOUNT));
1892		} else {
1893			done = true;
1894		}
1895
1896	} else if (urb->status == -EINPROGRESS) {
1897		/* if no errors, be sure a packet is ready for unloading */
1898		if (unlikely(!(rx_csr & MUSB_RXCSR_RXPKTRDY))) {
1899			status = -EPROTO;
1900			ERR("Rx interrupt with no errors or packet!\n");
1901
1902			/* FIXME this is another "SHOULD NEVER HAPPEN" */
1903
1904/* SCRUB (RX) */
1905			/* do the proper sequence to abort the transfer */
1906			musb_ep_select(mbase, epnum);
1907			val &= ~MUSB_RXCSR_H_REQPKT;
1908			musb_writew(epio, MUSB_RXCSR, val);
1909			goto finish;
1910		}
1911
1912		/* we are expecting IN packets */
1913		if ((musb_dma_inventra(musb) || musb_dma_ux500(musb) ||
1914		    musb_dma_cppi41(musb)) && dma) {
1915			musb_dbg(hw_ep->musb,
1916				"RX%d count %d, buffer 0x%llx len %d/%d",
1917				epnum, musb_readw(epio, MUSB_RXCOUNT),
1918				(unsigned long long) urb->transfer_dma
1919				+ urb->actual_length,
1920				qh->offset,
1921				urb->transfer_buffer_length);
1922
1923			if (musb_rx_dma_in_inventra_cppi41(c, hw_ep, qh, urb,
1924							   xfer_len, iso_err))
1925				goto finish;
1926			else
1927				dev_err(musb->controller, "error: rx_dma failed\n");
1928		}
1929
1930		if (!dma) {
1931			unsigned int received_len;
1932
1933			/* Unmap the buffer so that CPU can use it */
1934			usb_hcd_unmap_urb_for_dma(musb->hcd, urb);
1935
1936			/*
1937			 * We need to map sg if the transfer_buffer is
1938			 * NULL.
1939			 */
1940			if (!urb->transfer_buffer) {
1941				qh->use_sg = true;
1942				sg_miter_start(&qh->sg_miter, urb->sg, 1,
1943						sg_flags);
1944			}
1945
1946			if (qh->use_sg) {
1947				if (!sg_miter_next(&qh->sg_miter)) {
1948					dev_err(musb->controller, "error: sg list empty\n");
1949					sg_miter_stop(&qh->sg_miter);
1950					status = -EINVAL;
1951					done = true;
1952					goto finish;
1953				}
1954				urb->transfer_buffer = qh->sg_miter.addr;
1955				received_len = urb->actual_length;
1956				qh->offset = 0x0;
1957				done = musb_host_packet_rx(musb, urb, epnum,
1958						iso_err);
1959				/* Calculate the number of bytes received */
1960				received_len = urb->actual_length -
1961					received_len;
1962				qh->sg_miter.consumed = received_len;
1963				sg_miter_stop(&qh->sg_miter);
1964			} else {
1965				done = musb_host_packet_rx(musb, urb,
1966						epnum, iso_err);
1967			}
1968			musb_dbg(musb, "read %spacket", done ? "last " : "");
1969		}
1970	}
1971
1972finish:
1973	urb->actual_length += xfer_len;
1974	qh->offset += xfer_len;
1975	if (done) {
1976		if (qh->use_sg) {
1977			qh->use_sg = false;
1978			urb->transfer_buffer = NULL;
1979		}
1980
1981		if (urb->status == -EINPROGRESS)
1982			urb->status = status;
1983		musb_advance_schedule(musb, urb, hw_ep, USB_DIR_IN);
1984	}
1985}
1986
1987/* schedule nodes correspond to peripheral endpoints, like an OHCI QH.
1988 * the software schedule associates multiple such nodes with a given
1989 * host side hardware endpoint + direction; scheduling may activate
1990 * that hardware endpoint.
1991 */
1992static int musb_schedule(
1993	struct musb		*musb,
1994	struct musb_qh		*qh,
1995	int			is_in)
1996{
1997	int			idle = 0;
1998	int			best_diff;
1999	int			best_end, epnum;
2000	struct musb_hw_ep	*hw_ep = NULL;
2001	struct list_head	*head = NULL;
2002	u8			toggle;
2003	u8			txtype;
2004	struct urb		*urb = next_urb(qh);
2005
2006	/* use fixed hardware for control and bulk */
2007	if (qh->type == USB_ENDPOINT_XFER_CONTROL) {
2008		head = &musb->control;
2009		hw_ep = musb->control_ep;
2010		goto success;
2011	}
2012
2013	/* else, periodic transfers get muxed to other endpoints */
2014
2015	/*
2016	 * We know this qh hasn't been scheduled, so all we need to do
2017	 * is choose which hardware endpoint to put it on ...
2018	 *
2019	 * REVISIT what we really want here is a regular schedule tree
2020	 * like e.g. OHCI uses.
2021	 */
2022	best_diff = 4096;
2023	best_end = -1;
2024
2025	for (epnum = 1, hw_ep = musb->endpoints + 1;
2026			epnum < musb->nr_endpoints;
2027			epnum++, hw_ep++) {
2028		int	diff;
2029
2030		if (musb_ep_get_qh(hw_ep, is_in) != NULL)
2031			continue;
2032
2033		if (hw_ep == musb->bulk_ep)
2034			continue;
2035
2036		if (is_in)
2037			diff = hw_ep->max_packet_sz_rx;
2038		else
2039			diff = hw_ep->max_packet_sz_tx;
2040		diff -= (qh->maxpacket * qh->hb_mult);
2041
2042		if (diff >= 0 && best_diff > diff) {
2043
2044			/*
2045			 * Mentor controller has a bug in that if we schedule
2046			 * a BULK Tx transfer on an endpoint that had earlier
2047			 * handled ISOC then the BULK transfer has to start on
2048			 * a zero toggle.  If the BULK transfer starts on a 1
2049			 * toggle then this transfer will fail as the mentor
2050			 * controller starts the Bulk transfer on a 0 toggle
2051			 * irrespective of the programming of the toggle bits
2052			 * in the TXCSR register.  Check for this condition
2053			 * while allocating the EP for a Tx Bulk transfer.  If
2054			 * so skip this EP.
2055			 */
2056			hw_ep = musb->endpoints + epnum;
2057			toggle = usb_gettoggle(urb->dev, qh->epnum, !is_in);
2058			txtype = (musb_readb(hw_ep->regs, MUSB_TXTYPE)
2059					>> 4) & 0x3;
2060			if (!is_in && (qh->type == USB_ENDPOINT_XFER_BULK) &&
2061				toggle && (txtype == USB_ENDPOINT_XFER_ISOC))
2062				continue;
2063
2064			best_diff = diff;
2065			best_end = epnum;
2066		}
2067	}
2068	/* use bulk reserved ep1 if no other ep is free */
2069	if (best_end < 0 && qh->type == USB_ENDPOINT_XFER_BULK) {
2070		hw_ep = musb->bulk_ep;
2071		if (is_in)
2072			head = &musb->in_bulk;
2073		else
2074			head = &musb->out_bulk;
2075
2076		/* Enable bulk RX/TX NAK timeout scheme when bulk requests are
2077		 * multiplexed. This scheme does not work in high speed to full
2078		 * speed scenario as NAK interrupts are not coming from a
2079		 * full speed device connected to a high speed device.
2080		 * NAK timeout interval is 8 (128 uframe or 16ms) for HS and
2081		 * 4 (8 frame or 8ms) for FS device.
2082		 */
2083		if (qh->dev)
2084			qh->intv_reg =
2085				(USB_SPEED_HIGH == qh->dev->speed) ? 8 : 4;
2086		goto success;
2087	} else if (best_end < 0) {
2088		dev_err(musb->controller,
2089				"%s hwep alloc failed for %dx%d\n",
2090				musb_ep_xfertype_string(qh->type),
2091				qh->hb_mult, qh->maxpacket);
2092		return -ENOSPC;
2093	}
2094
2095	idle = 1;
2096	qh->mux = 0;
2097	hw_ep = musb->endpoints + best_end;
2098	musb_dbg(musb, "qh %p periodic slot %d", qh, best_end);
2099success:
2100	if (head) {
2101		idle = list_empty(head);
2102		list_add_tail(&qh->ring, head);
2103		qh->mux = 1;
2104	}
2105	qh->hw_ep = hw_ep;
2106	qh->hep->hcpriv = qh;
2107	if (idle)
2108		musb_start_urb(musb, is_in, qh);
2109	return 0;
2110}
2111
2112static int musb_urb_enqueue(
2113	struct usb_hcd			*hcd,
2114	struct urb			*urb,
2115	gfp_t				mem_flags)
2116{
2117	unsigned long			flags;
2118	struct musb			*musb = hcd_to_musb(hcd);
2119	struct usb_host_endpoint	*hep = urb->ep;
2120	struct musb_qh			*qh;
2121	struct usb_endpoint_descriptor	*epd = &hep->desc;
2122	int				ret;
2123	unsigned			type_reg;
2124	unsigned			interval;
2125
2126	/* host role must be active */
2127	if (!is_host_active(musb) || !musb->is_active)
2128		return -ENODEV;
2129
2130	trace_musb_urb_enq(musb, urb);
2131
2132	spin_lock_irqsave(&musb->lock, flags);
2133	ret = usb_hcd_link_urb_to_ep(hcd, urb);
2134	qh = ret ? NULL : hep->hcpriv;
2135	if (qh)
2136		urb->hcpriv = qh;
2137	spin_unlock_irqrestore(&musb->lock, flags);
2138
2139	/* DMA mapping was already done, if needed, and this urb is on
2140	 * hep->urb_list now ... so we're done, unless hep wasn't yet
2141	 * scheduled onto a live qh.
2142	 *
2143	 * REVISIT best to keep hep->hcpriv valid until the endpoint gets
2144	 * disabled, testing for empty qh->ring and avoiding qh setup costs
2145	 * except for the first urb queued after a config change.
2146	 */
2147	if (qh || ret)
2148		return ret;
2149
2150	/* Allocate and initialize qh, minimizing the work done each time
2151	 * hw_ep gets reprogrammed, or with irqs blocked.  Then schedule it.
2152	 *
2153	 * REVISIT consider a dedicated qh kmem_cache, so it's harder
2154	 * for bugs in other kernel code to break this driver...
2155	 */
2156	qh = kzalloc(sizeof *qh, mem_flags);
2157	if (!qh) {
2158		spin_lock_irqsave(&musb->lock, flags);
2159		usb_hcd_unlink_urb_from_ep(hcd, urb);
2160		spin_unlock_irqrestore(&musb->lock, flags);
2161		return -ENOMEM;
2162	}
2163
2164	qh->hep = hep;
2165	qh->dev = urb->dev;
2166	INIT_LIST_HEAD(&qh->ring);
2167	qh->is_ready = 1;
2168
2169	qh->maxpacket = usb_endpoint_maxp(epd);
2170	qh->type = usb_endpoint_type(epd);
2171
2172	/* Bits 11 & 12 of wMaxPacketSize encode high bandwidth multiplier.
2173	 * Some musb cores don't support high bandwidth ISO transfers; and
2174	 * we don't (yet!) support high bandwidth interrupt transfers.
2175	 */
2176	qh->hb_mult = usb_endpoint_maxp_mult(epd);
2177	if (qh->hb_mult > 1) {
2178		int ok = (qh->type == USB_ENDPOINT_XFER_ISOC);
2179
2180		if (ok)
2181			ok = (usb_pipein(urb->pipe) && musb->hb_iso_rx)
2182				|| (usb_pipeout(urb->pipe) && musb->hb_iso_tx);
2183		if (!ok) {
2184			dev_err(musb->controller,
2185				"high bandwidth %s (%dx%d) not supported\n",
2186				musb_ep_xfertype_string(qh->type),
2187				qh->hb_mult, qh->maxpacket & 0x7ff);
2188			ret = -EMSGSIZE;
2189			goto done;
2190		}
2191		qh->maxpacket &= 0x7ff;
2192	}
2193
2194	qh->epnum = usb_endpoint_num(epd);
2195
2196	/* NOTE: urb->dev->devnum is wrong during SET_ADDRESS */
2197	qh->addr_reg = (u8) usb_pipedevice(urb->pipe);
2198
2199	/* precompute rxtype/txtype/type0 register */
2200	type_reg = (qh->type << 4) | qh->epnum;
2201	switch (urb->dev->speed) {
2202	case USB_SPEED_LOW:
2203		type_reg |= 0xc0;
2204		break;
2205	case USB_SPEED_FULL:
2206		type_reg |= 0x80;
2207		break;
2208	default:
2209		type_reg |= 0x40;
2210	}
2211	qh->type_reg = type_reg;
2212
2213	/* Precompute RXINTERVAL/TXINTERVAL register */
2214	switch (qh->type) {
2215	case USB_ENDPOINT_XFER_INT:
2216		/*
2217		 * Full/low speeds use the  linear encoding,
2218		 * high speed uses the logarithmic encoding.
2219		 */
2220		if (urb->dev->speed <= USB_SPEED_FULL) {
2221			interval = max_t(u8, epd->bInterval, 1);
2222			break;
2223		}
2224		fallthrough;
2225	case USB_ENDPOINT_XFER_ISOC:
2226		/* ISO always uses logarithmic encoding */
2227		interval = min_t(u8, epd->bInterval, 16);
2228		break;
2229	default:
2230		/* REVISIT we actually want to use NAK limits, hinting to the
2231		 * transfer scheduling logic to try some other qh, e.g. try
2232		 * for 2 msec first:
2233		 *
2234		 * interval = (USB_SPEED_HIGH == urb->dev->speed) ? 16 : 2;
2235		 *
2236		 * The downside of disabling this is that transfer scheduling
2237		 * gets VERY unfair for nonperiodic transfers; a misbehaving
2238		 * peripheral could make that hurt.  That's perfectly normal
2239		 * for reads from network or serial adapters ... so we have
2240		 * partial NAKlimit support for bulk RX.
2241		 *
2242		 * The upside of disabling it is simpler transfer scheduling.
2243		 */
2244		interval = 0;
2245	}
2246	qh->intv_reg = interval;
2247
2248	/* precompute addressing for external hub/tt ports */
2249	if (musb->is_multipoint) {
2250		struct usb_device	*parent = urb->dev->parent;
2251
2252		if (parent != hcd->self.root_hub) {
2253			qh->h_addr_reg = (u8) parent->devnum;
2254
2255			/* set up tt info if needed */
2256			if (urb->dev->tt) {
2257				qh->h_port_reg = (u8) urb->dev->ttport;
2258				if (urb->dev->tt->hub)
2259					qh->h_addr_reg =
2260						(u8) urb->dev->tt->hub->devnum;
2261				if (urb->dev->tt->multi)
2262					qh->h_addr_reg |= 0x80;
2263			}
2264		}
2265	}
2266
2267	/* invariant: hep->hcpriv is null OR the qh that's already scheduled.
2268	 * until we get real dma queues (with an entry for each urb/buffer),
2269	 * we only have work to do in the former case.
2270	 */
2271	spin_lock_irqsave(&musb->lock, flags);
2272	if (hep->hcpriv || !next_urb(qh)) {
2273		/* some concurrent activity submitted another urb to hep...
2274		 * odd, rare, error prone, but legal.
2275		 */
2276		kfree(qh);
2277		qh = NULL;
2278		ret = 0;
2279	} else
2280		ret = musb_schedule(musb, qh,
2281				epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK);
2282
2283	if (ret == 0) {
2284		urb->hcpriv = qh;
2285		/* FIXME set urb->start_frame for iso/intr, it's tested in
2286		 * musb_start_urb(), but otherwise only konicawc cares ...
2287		 */
2288	}
2289	spin_unlock_irqrestore(&musb->lock, flags);
2290
2291done:
2292	if (ret != 0) {
2293		spin_lock_irqsave(&musb->lock, flags);
2294		usb_hcd_unlink_urb_from_ep(hcd, urb);
2295		spin_unlock_irqrestore(&musb->lock, flags);
2296		kfree(qh);
2297	}
2298	return ret;
2299}
2300
2301
2302/*
2303 * abort a transfer that's at the head of a hardware queue.
2304 * called with controller locked, irqs blocked
2305 * that hardware queue advances to the next transfer, unless prevented
2306 */
2307static int musb_cleanup_urb(struct urb *urb, struct musb_qh *qh)
2308{
2309	struct musb_hw_ep	*ep = qh->hw_ep;
2310	struct musb		*musb = ep->musb;
2311	void __iomem		*epio = ep->regs;
2312	unsigned		hw_end = ep->epnum;
2313	void __iomem		*regs = ep->musb->mregs;
2314	int			is_in = usb_pipein(urb->pipe);
2315	int			status = 0;
2316	u16			csr;
2317	struct dma_channel	*dma = NULL;
2318
2319	musb_ep_select(regs, hw_end);
2320
2321	if (is_dma_capable()) {
2322		dma = is_in ? ep->rx_channel : ep->tx_channel;
2323		if (dma) {
2324			status = ep->musb->dma_controller->channel_abort(dma);
2325			musb_dbg(musb, "abort %cX%d DMA for urb %p --> %d",
2326				is_in ? 'R' : 'T', ep->epnum,
2327				urb, status);
2328			urb->actual_length += dma->actual_len;
2329		}
2330	}
2331
2332	/* turn off DMA requests, discard state, stop polling ... */
2333	if (ep->epnum && is_in) {
2334		/* giveback saves bulk toggle */
2335		csr = musb_h_flush_rxfifo(ep, 0);
2336
2337		/* clear the endpoint's irq status here to avoid bogus irqs */
2338		if (is_dma_capable() && dma)
2339			musb_platform_clear_ep_rxintr(musb, ep->epnum);
2340	} else if (ep->epnum) {
2341		musb_h_tx_flush_fifo(ep);
2342		csr = musb_readw(epio, MUSB_TXCSR);
2343		csr &= ~(MUSB_TXCSR_AUTOSET
2344			| MUSB_TXCSR_DMAENAB
2345			| MUSB_TXCSR_H_RXSTALL
2346			| MUSB_TXCSR_H_NAKTIMEOUT
2347			| MUSB_TXCSR_H_ERROR
2348			| MUSB_TXCSR_TXPKTRDY);
2349		musb_writew(epio, MUSB_TXCSR, csr);
2350		/* REVISIT may need to clear FLUSHFIFO ... */
2351		musb_writew(epio, MUSB_TXCSR, csr);
2352		/* flush cpu writebuffer */
2353		csr = musb_readw(epio, MUSB_TXCSR);
2354	} else  {
2355		musb_h_ep0_flush_fifo(ep);
2356	}
2357	if (status == 0)
2358		musb_advance_schedule(ep->musb, urb, ep, is_in);
2359	return status;
2360}
2361
2362static int musb_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
2363{
2364	struct musb		*musb = hcd_to_musb(hcd);
2365	struct musb_qh		*qh;
2366	unsigned long		flags;
2367	int			is_in  = usb_pipein(urb->pipe);
2368	int			ret;
2369
2370	trace_musb_urb_deq(musb, urb);
2371
2372	spin_lock_irqsave(&musb->lock, flags);
2373	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
2374	if (ret)
2375		goto done;
2376
2377	qh = urb->hcpriv;
2378	if (!qh)
2379		goto done;
2380
2381	/*
2382	 * Any URB not actively programmed into endpoint hardware can be
2383	 * immediately given back; that's any URB not at the head of an
2384	 * endpoint queue, unless someday we get real DMA queues.  And even
2385	 * if it's at the head, it might not be known to the hardware...
2386	 *
2387	 * Otherwise abort current transfer, pending DMA, etc.; urb->status
2388	 * has already been updated.  This is a synchronous abort; it'd be
2389	 * OK to hold off until after some IRQ, though.
2390	 *
2391	 * NOTE: qh is invalid unless !list_empty(&hep->urb_list)
2392	 */
2393	if (!qh->is_ready
2394			|| urb->urb_list.prev != &qh->hep->urb_list
2395			|| musb_ep_get_qh(qh->hw_ep, is_in) != qh) {
2396		int	ready = qh->is_ready;
2397
2398		qh->is_ready = 0;
2399		musb_giveback(musb, urb, 0);
2400		qh->is_ready = ready;
2401
2402		/* If nothing else (usually musb_giveback) is using it
2403		 * and its URB list has emptied, recycle this qh.
2404		 */
2405		if (ready && list_empty(&qh->hep->urb_list)) {
2406			musb_ep_set_qh(qh->hw_ep, is_in, NULL);
2407			qh->hep->hcpriv = NULL;
2408			list_del(&qh->ring);
2409			kfree(qh);
2410		}
2411	} else
2412		ret = musb_cleanup_urb(urb, qh);
2413done:
2414	spin_unlock_irqrestore(&musb->lock, flags);
2415	return ret;
2416}
2417
2418/* disable an endpoint */
2419static void
2420musb_h_disable(struct usb_hcd *hcd, struct usb_host_endpoint *hep)
2421{
2422	u8			is_in = hep->desc.bEndpointAddress & USB_DIR_IN;
2423	unsigned long		flags;
2424	struct musb		*musb = hcd_to_musb(hcd);
2425	struct musb_qh		*qh;
2426	struct urb		*urb;
2427
2428	spin_lock_irqsave(&musb->lock, flags);
2429
2430	qh = hep->hcpriv;
2431	if (qh == NULL)
2432		goto exit;
2433
2434	/* NOTE: qh is invalid unless !list_empty(&hep->urb_list) */
2435
2436	/* Kick the first URB off the hardware, if needed */
2437	qh->is_ready = 0;
2438	if (musb_ep_get_qh(qh->hw_ep, is_in) == qh) {
2439		urb = next_urb(qh);
2440
2441		/* make software (then hardware) stop ASAP */
2442		if (!urb->unlinked)
2443			urb->status = -ESHUTDOWN;
2444
2445		/* cleanup */
2446		musb_cleanup_urb(urb, qh);
2447
2448		/* Then nuke all the others ... and advance the
2449		 * queue on hw_ep (e.g. bulk ring) when we're done.
2450		 */
2451		while (!list_empty(&hep->urb_list)) {
2452			urb = next_urb(qh);
2453			urb->status = -ESHUTDOWN;
2454			musb_advance_schedule(musb, urb, qh->hw_ep, is_in);
2455		}
2456	} else {
2457		/* Just empty the queue; the hardware is busy with
2458		 * other transfers, and since !qh->is_ready nothing
2459		 * will activate any of these as it advances.
2460		 */
2461		while (!list_empty(&hep->urb_list))
2462			musb_giveback(musb, next_urb(qh), -ESHUTDOWN);
2463
2464		hep->hcpriv = NULL;
2465		list_del(&qh->ring);
2466		kfree(qh);
2467	}
2468exit:
2469	spin_unlock_irqrestore(&musb->lock, flags);
2470}
2471
2472static int musb_h_get_frame_number(struct usb_hcd *hcd)
2473{
2474	struct musb	*musb = hcd_to_musb(hcd);
2475
2476	return musb_readw(musb->mregs, MUSB_FRAME);
2477}
2478
2479static int musb_h_start(struct usb_hcd *hcd)
2480{
2481	struct musb	*musb = hcd_to_musb(hcd);
2482
2483	/* NOTE: musb_start() is called when the hub driver turns
2484	 * on port power, or when (OTG) peripheral starts.
2485	 */
2486	hcd->state = HC_STATE_RUNNING;
2487	musb->port1_status = 0;
2488	return 0;
2489}
2490
2491static void musb_h_stop(struct usb_hcd *hcd)
2492{
2493	musb_stop(hcd_to_musb(hcd));
2494	hcd->state = HC_STATE_HALT;
2495}
2496
2497static int musb_bus_suspend(struct usb_hcd *hcd)
2498{
2499	struct musb	*musb = hcd_to_musb(hcd);
2500	u8		devctl;
2501	int		ret;
2502
2503	ret = musb_port_suspend(musb, true);
2504	if (ret)
2505		return ret;
2506
2507	if (!is_host_active(musb))
2508		return 0;
2509
2510	switch (musb_get_state(musb)) {
2511	case OTG_STATE_A_SUSPEND:
2512		return 0;
2513	case OTG_STATE_A_WAIT_VRISE:
2514		/* ID could be grounded even if there's no device
2515		 * on the other end of the cable.  NOTE that the
2516		 * A_WAIT_VRISE timers are messy with MUSB...
2517		 */
2518		devctl = musb_readb(musb->mregs, MUSB_DEVCTL);
2519		if ((devctl & MUSB_DEVCTL_VBUS) == MUSB_DEVCTL_VBUS)
2520			musb_set_state(musb, OTG_STATE_A_WAIT_BCON);
2521		break;
2522	default:
2523		break;
2524	}
2525
2526	if (musb->is_active) {
2527		WARNING("trying to suspend as %s while active\n",
2528			musb_otg_state_string(musb));
2529		return -EBUSY;
2530	} else
2531		return 0;
2532}
2533
2534static int musb_bus_resume(struct usb_hcd *hcd)
2535{
2536	struct musb *musb = hcd_to_musb(hcd);
2537
2538	if (musb->config &&
2539	    musb->config->host_port_deassert_reset_at_resume)
2540		musb_port_reset(musb, false);
2541
2542	return 0;
2543}
2544
2545#ifndef CONFIG_MUSB_PIO_ONLY
2546
2547#define MUSB_USB_DMA_ALIGN 4
2548
2549struct musb_temp_buffer {
2550	void *kmalloc_ptr;
2551	void *old_xfer_buffer;
2552	u8 data[];
2553};
2554
2555static void musb_free_temp_buffer(struct urb *urb)
2556{
2557	enum dma_data_direction dir;
2558	struct musb_temp_buffer *temp;
2559	size_t length;
2560
2561	if (!(urb->transfer_flags & URB_ALIGNED_TEMP_BUFFER))
2562		return;
2563
2564	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
2565
2566	temp = container_of(urb->transfer_buffer, struct musb_temp_buffer,
2567			    data);
2568
2569	if (dir == DMA_FROM_DEVICE) {
2570		if (usb_pipeisoc(urb->pipe))
2571			length = urb->transfer_buffer_length;
2572		else
2573			length = urb->actual_length;
2574
2575		memcpy(temp->old_xfer_buffer, temp->data, length);
2576	}
2577	urb->transfer_buffer = temp->old_xfer_buffer;
2578	kfree(temp->kmalloc_ptr);
2579
2580	urb->transfer_flags &= ~URB_ALIGNED_TEMP_BUFFER;
2581}
2582
2583static int musb_alloc_temp_buffer(struct urb *urb, gfp_t mem_flags)
2584{
2585	enum dma_data_direction dir;
2586	struct musb_temp_buffer *temp;
2587	void *kmalloc_ptr;
2588	size_t kmalloc_size;
2589
2590	if (urb->num_sgs || urb->sg ||
2591	    urb->transfer_buffer_length == 0 ||
2592	    !((uintptr_t)urb->transfer_buffer & (MUSB_USB_DMA_ALIGN - 1)))
2593		return 0;
2594
2595	dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
2596
2597	/* Allocate a buffer with enough padding for alignment */
2598	kmalloc_size = urb->transfer_buffer_length +
2599		sizeof(struct musb_temp_buffer) + MUSB_USB_DMA_ALIGN - 1;
2600
2601	kmalloc_ptr = kmalloc(kmalloc_size, mem_flags);
2602	if (!kmalloc_ptr)
2603		return -ENOMEM;
2604
2605	/* Position our struct temp_buffer such that data is aligned */
2606	temp = PTR_ALIGN(kmalloc_ptr, MUSB_USB_DMA_ALIGN);
2607
2608
2609	temp->kmalloc_ptr = kmalloc_ptr;
2610	temp->old_xfer_buffer = urb->transfer_buffer;
2611	if (dir == DMA_TO_DEVICE)
2612		memcpy(temp->data, urb->transfer_buffer,
2613		       urb->transfer_buffer_length);
2614	urb->transfer_buffer = temp->data;
2615
2616	urb->transfer_flags |= URB_ALIGNED_TEMP_BUFFER;
2617
2618	return 0;
2619}
2620
2621static int musb_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
2622				      gfp_t mem_flags)
2623{
2624	struct musb	*musb = hcd_to_musb(hcd);
2625	int ret;
2626
2627	/*
2628	 * The DMA engine in RTL1.8 and above cannot handle
2629	 * DMA addresses that are not aligned to a 4 byte boundary.
2630	 * For such engine implemented (un)map_urb_for_dma hooks.
2631	 * Do not use these hooks for RTL<1.8
2632	 */
2633	if (musb->hwvers < MUSB_HWVERS_1800)
2634		return usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
2635
2636	ret = musb_alloc_temp_buffer(urb, mem_flags);
2637	if (ret)
2638		return ret;
2639
2640	ret = usb_hcd_map_urb_for_dma(hcd, urb, mem_flags);
2641	if (ret)
2642		musb_free_temp_buffer(urb);
2643
2644	return ret;
2645}
2646
2647static void musb_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
2648{
2649	struct musb	*musb = hcd_to_musb(hcd);
2650
2651	usb_hcd_unmap_urb_for_dma(hcd, urb);
2652
2653	/* Do not use this hook for RTL<1.8 (see description above) */
2654	if (musb->hwvers < MUSB_HWVERS_1800)
2655		return;
2656
2657	musb_free_temp_buffer(urb);
2658}
2659#endif /* !CONFIG_MUSB_PIO_ONLY */
2660
2661static const struct hc_driver musb_hc_driver = {
2662	.description		= "musb-hcd",
2663	.product_desc		= "MUSB HDRC host driver",
2664	.hcd_priv_size		= sizeof(struct musb *),
2665	.flags			= HCD_USB2 | HCD_DMA | HCD_MEMORY,
2666
2667	/* not using irq handler or reset hooks from usbcore, since
2668	 * those must be shared with peripheral code for OTG configs
2669	 */
2670
2671	.start			= musb_h_start,
2672	.stop			= musb_h_stop,
2673
2674	.get_frame_number	= musb_h_get_frame_number,
2675
2676	.urb_enqueue		= musb_urb_enqueue,
2677	.urb_dequeue		= musb_urb_dequeue,
2678	.endpoint_disable	= musb_h_disable,
2679
2680#ifndef CONFIG_MUSB_PIO_ONLY
2681	.map_urb_for_dma	= musb_map_urb_for_dma,
2682	.unmap_urb_for_dma	= musb_unmap_urb_for_dma,
2683#endif
2684
2685	.hub_status_data	= musb_hub_status_data,
2686	.hub_control		= musb_hub_control,
2687	.bus_suspend		= musb_bus_suspend,
2688	.bus_resume		= musb_bus_resume,
2689	/* .start_port_reset	= NULL, */
2690	/* .hub_irq_enable	= NULL, */
2691};
2692
2693int musb_host_alloc(struct musb *musb)
2694{
2695	struct device	*dev = musb->controller;
2696
2697	/* usbcore sets dev->driver_data to hcd, and sometimes uses that... */
2698	musb->hcd = usb_create_hcd(&musb_hc_driver, dev, dev_name(dev));
2699	if (!musb->hcd)
2700		return -EINVAL;
2701
2702	*musb->hcd->hcd_priv = (unsigned long) musb;
2703	musb->hcd->self.uses_pio_for_control = 1;
2704	musb->hcd->uses_new_polling = 1;
2705	musb->hcd->has_tt = 1;
2706
2707	return 0;
2708}
2709
2710void musb_host_cleanup(struct musb *musb)
2711{
2712	if (musb->port_mode == MUSB_PERIPHERAL)
2713		return;
2714	usb_remove_hcd(musb->hcd);
2715}
2716
2717void musb_host_free(struct musb *musb)
2718{
2719	usb_put_hcd(musb->hcd);
2720}
2721
2722int musb_host_setup(struct musb *musb, int power_budget)
2723{
2724	int ret;
2725	struct usb_hcd *hcd = musb->hcd;
2726
2727	if (musb->port_mode == MUSB_HOST) {
2728		MUSB_HST_MODE(musb);
2729		musb_set_state(musb, OTG_STATE_A_IDLE);
2730	}
2731
2732	if (musb->xceiv) {
2733		otg_set_host(musb->xceiv->otg, &hcd->self);
2734		musb->xceiv->otg->host = &hcd->self;
2735	} else {
2736		phy_set_mode(musb->phy, PHY_MODE_USB_HOST);
2737	}
2738
2739	/* don't support otg protocols */
2740	hcd->self.otg_port = 0;
2741	hcd->power_budget = 2 * (power_budget ? : 250);
2742	hcd->skip_phy_initialization = 1;
2743
2744	ret = usb_add_hcd(hcd, 0, 0);
2745	if (ret < 0)
2746		return ret;
2747
2748	device_wakeup_enable(hcd->self.controller);
2749	return 0;
2750}
2751
2752void musb_host_resume_root_hub(struct musb *musb)
2753{
2754	usb_hcd_resume_root_hub(musb->hcd);
2755}
2756
2757void musb_host_poke_root_hub(struct musb *musb)
2758{
2759	MUSB_HST_MODE(musb);
2760	if (musb->hcd->status_urb)
2761		usb_hcd_poll_rh_status(musb->hcd);
2762	else
2763		usb_hcd_resume_root_hub(musb->hcd);
2764}