1/*
   2 * MAX3421 Host Controller driver for USB.
   3 *
   4 * Author: David Mosberger-Tang <davidm@egauge.net>
   5 *
   6 * (C) Copyright 2014 David Mosberger-Tang <davidm@egauge.net>
   7 *
   8 * MAX3421 is a chip implementing a USB 2.0 Full-/Low-Speed host
   9 * controller on a SPI bus.
  10 *
  11 * Based on:
  12 *	o MAX3421E datasheet
  13 *		http://datasheets.maximintegrated.com/en/ds/MAX3421E.pdf
  14 *	o MAX3421E Programming Guide
  15 *		http://www.hdl.co.jp/ftpdata/utl-001/AN3785.pdf
  16 *	o gadget/dummy_hcd.c
  17 *		For USB HCD implementation.
  18 *	o Arduino MAX3421 driver
  19 *	     https://github.com/felis/USB_Host_Shield_2.0/blob/master/Usb.cpp
  20 *
  21 * This file is licenced under the GPL v2.
  22 *
  23 * Important note on worst-case (full-speed) packet size constraints
  24 * (See USB 2.0 Section 5.6.3 and following):
  25 *
  26 *	- control:	  64 bytes
  27 *	- isochronous:	1023 bytes
  28 *	- interrupt:	  64 bytes
  29 *	- bulk:		  64 bytes
  30 *
  31 * Since the MAX3421 FIFO size is 64 bytes, we do not have to work about
  32 * multi-FIFO writes/reads for a single USB packet *except* for isochronous
  33 * transfers.  We don't support isochronous transfers at this time, so we
  34 * just assume that a USB packet always fits into a single FIFO buffer.
  35 *
  36 * NOTE: The June 2006 version of "MAX3421E Programming Guide"
  37 * (AN3785) has conflicting info for the RCVDAVIRQ bit:
  38 *
  39 *	The description of RCVDAVIRQ says "The CPU *must* clear
  40 *	this IRQ bit (by writing a 1 to it) before reading the
  41 *	RCVFIFO data.
  42 *
  43 * However, the earlier section on "Programming BULK-IN
  44 * Transfers" says * that:
  45 *
  46 *	After the CPU retrieves the data, it clears the
  47 *	RCVDAVIRQ bit.
  48 *
  49 * The December 2006 version has been corrected and it consistently
  50 * states the second behavior is the correct one.
  51 *
  52 * Synchronous SPI transactions sleep so we can't perform any such
  53 * transactions while holding a spin-lock (and/or while interrupts are
  54 * masked).  To achieve this, all SPI transactions are issued from a
  55 * single thread (max3421_spi_thread).
  56 */
  57
  58#include <linux/jiffies.h>
  59#include <linux/module.h>
  60#include <linux/spi/spi.h>
  61#include <linux/usb.h>
  62#include <linux/usb/hcd.h>
 
  63
  64#include <linux/platform_data/max3421-hcd.h>
  65
  66#define DRIVER_DESC	"MAX3421 USB Host-Controller Driver"
  67#define DRIVER_VERSION	"1.0"
  68
  69/* 11-bit counter that wraps around (USB 2.0 Section 8.3.3): */
  70#define USB_MAX_FRAME_NUMBER	0x7ff
  71#define USB_MAX_RETRIES		3 /* # of retries before error is reported */
  72
  73/*
  74 * Max. # of times we're willing to retransmit a request immediately in
  75 * resposne to a NAK.  Afterwards, we fall back on trying once a frame.
  76 */
  77#define NAK_MAX_FAST_RETRANSMITS	2
  78
  79#define POWER_BUDGET	500	/* in mA; use 8 for low-power port testing */
  80
  81/* Port-change mask: */
  82#define PORT_C_MASK	((USB_PORT_STAT_C_CONNECTION |	\
  83			  USB_PORT_STAT_C_ENABLE |	\
  84			  USB_PORT_STAT_C_SUSPEND |	\
  85			  USB_PORT_STAT_C_OVERCURRENT | \
  86			  USB_PORT_STAT_C_RESET) << 16)
  87
 
 
  88enum max3421_rh_state {
  89	MAX3421_RH_RESET,
  90	MAX3421_RH_SUSPENDED,
  91	MAX3421_RH_RUNNING
  92};
  93
  94enum pkt_state {
  95	PKT_STATE_SETUP,	/* waiting to send setup packet to ctrl pipe */
  96	PKT_STATE_TRANSFER,	/* waiting to xfer transfer_buffer */
  97	PKT_STATE_TERMINATE	/* waiting to terminate control transfer */
  98};
  99
 100enum scheduling_pass {
 101	SCHED_PASS_PERIODIC,
 102	SCHED_PASS_NON_PERIODIC,
 103	SCHED_PASS_DONE
 104};
 105
 106/* Bit numbers for max3421_hcd->todo: */
 107enum {
 108	ENABLE_IRQ = 0,
 109	RESET_HCD,
 110	RESET_PORT,
 111	CHECK_UNLINK,
 112	IOPIN_UPDATE
 113};
 114
 115struct max3421_dma_buf {
 116	u8 data[2];
 117};
 118
 119struct max3421_hcd {
 120	spinlock_t lock;
 121
 122	struct task_struct *spi_thread;
 123
 124	struct max3421_hcd *next;
 125
 126	enum max3421_rh_state rh_state;
 127	/* lower 16 bits contain port status, upper 16 bits the change mask: */
 128	u32 port_status;
 129
 130	unsigned active:1;
 131
 132	struct list_head ep_list;	/* list of EP's with work */
 133
 134	/*
 135	 * The following are owned by spi_thread (may be accessed by
 136	 * SPI-thread without acquiring the HCD lock:
 137	 */
 138	u8 rev;				/* chip revision */
 139	u16 frame_number;
 140	/*
 141	 * kmalloc'd buffers guaranteed to be in separate (DMA)
 142	 * cache-lines:
 143	 */
 144	struct max3421_dma_buf *tx;
 145	struct max3421_dma_buf *rx;
 146	/*
 147	 * URB we're currently processing.  Must not be reset to NULL
 148	 * unless MAX3421E chip is idle:
 149	 */
 150	struct urb *curr_urb;
 151	enum scheduling_pass sched_pass;
 152	struct usb_device *loaded_dev;	/* dev that's loaded into the chip */
 153	int loaded_epnum;		/* epnum whose toggles are loaded */
 154	int urb_done;			/* > 0 -> no errors, < 0: errno */
 155	size_t curr_len;
 156	u8 hien;
 157	u8 mode;
 158	u8 iopins[2];
 159	unsigned long todo;
 160#ifdef DEBUG
 161	unsigned long err_stat[16];
 162#endif
 163};
 164
 165struct max3421_ep {
 166	struct usb_host_endpoint *ep;
 167	struct list_head ep_list;
 168	u32 naks;
 169	u16 last_active;		/* frame # this ep was last active */
 170	enum pkt_state pkt_state;
 171	u8 retries;
 172	u8 retransmit;			/* packet needs retransmission */
 173};
 174
 175static struct max3421_hcd *max3421_hcd_list;
 176
 177#define MAX3421_FIFO_SIZE	64
 178
 179#define MAX3421_SPI_DIR_RD	0	/* read register from MAX3421 */
 180#define MAX3421_SPI_DIR_WR	1	/* write register to MAX3421 */
 181
 182/* SPI commands: */
 183#define MAX3421_SPI_DIR_SHIFT	1
 184#define MAX3421_SPI_REG_SHIFT	3
 185
 186#define MAX3421_REG_RCVFIFO	1
 187#define MAX3421_REG_SNDFIFO	2
 188#define MAX3421_REG_SUDFIFO	4
 189#define MAX3421_REG_RCVBC	6
 190#define MAX3421_REG_SNDBC	7
 191#define MAX3421_REG_USBIRQ	13
 192#define MAX3421_REG_USBIEN	14
 193#define MAX3421_REG_USBCTL	15
 194#define MAX3421_REG_CPUCTL	16
 195#define MAX3421_REG_PINCTL	17
 196#define MAX3421_REG_REVISION	18
 197#define MAX3421_REG_IOPINS1	20
 198#define MAX3421_REG_IOPINS2	21
 199#define MAX3421_REG_GPINIRQ	22
 200#define MAX3421_REG_GPINIEN	23
 201#define MAX3421_REG_GPINPOL	24
 202#define MAX3421_REG_HIRQ	25
 203#define MAX3421_REG_HIEN	26
 204#define MAX3421_REG_MODE	27
 205#define MAX3421_REG_PERADDR	28
 206#define MAX3421_REG_HCTL	29
 207#define MAX3421_REG_HXFR	30
 208#define MAX3421_REG_HRSL	31
 209
 210enum {
 211	MAX3421_USBIRQ_OSCOKIRQ_BIT = 0,
 212	MAX3421_USBIRQ_NOVBUSIRQ_BIT = 5,
 213	MAX3421_USBIRQ_VBUSIRQ_BIT
 214};
 215
 216enum {
 217	MAX3421_CPUCTL_IE_BIT = 0,
 218	MAX3421_CPUCTL_PULSEWID0_BIT = 6,
 219	MAX3421_CPUCTL_PULSEWID1_BIT
 220};
 221
 222enum {
 223	MAX3421_USBCTL_PWRDOWN_BIT = 4,
 224	MAX3421_USBCTL_CHIPRES_BIT
 225};
 226
 227enum {
 228	MAX3421_PINCTL_GPXA_BIT	= 0,
 229	MAX3421_PINCTL_GPXB_BIT,
 230	MAX3421_PINCTL_POSINT_BIT,
 231	MAX3421_PINCTL_INTLEVEL_BIT,
 232	MAX3421_PINCTL_FDUPSPI_BIT,
 233	MAX3421_PINCTL_EP0INAK_BIT,
 234	MAX3421_PINCTL_EP2INAK_BIT,
 235	MAX3421_PINCTL_EP3INAK_BIT,
 236};
 237
 238enum {
 239	MAX3421_HI_BUSEVENT_BIT = 0,	/* bus-reset/-resume */
 240	MAX3421_HI_RWU_BIT,		/* remote wakeup */
 241	MAX3421_HI_RCVDAV_BIT,		/* receive FIFO data available */
 242	MAX3421_HI_SNDBAV_BIT,		/* send buffer available */
 243	MAX3421_HI_SUSDN_BIT,		/* suspend operation done */
 244	MAX3421_HI_CONDET_BIT,		/* peripheral connect/disconnect */
 245	MAX3421_HI_FRAME_BIT,		/* frame generator */
 246	MAX3421_HI_HXFRDN_BIT,		/* host transfer done */
 247};
 248
 249enum {
 250	MAX3421_HCTL_BUSRST_BIT = 0,
 251	MAX3421_HCTL_FRMRST_BIT,
 252	MAX3421_HCTL_SAMPLEBUS_BIT,
 253	MAX3421_HCTL_SIGRSM_BIT,
 254	MAX3421_HCTL_RCVTOG0_BIT,
 255	MAX3421_HCTL_RCVTOG1_BIT,
 256	MAX3421_HCTL_SNDTOG0_BIT,
 257	MAX3421_HCTL_SNDTOG1_BIT
 258};
 259
 260enum {
 261	MAX3421_MODE_HOST_BIT = 0,
 262	MAX3421_MODE_LOWSPEED_BIT,
 263	MAX3421_MODE_HUBPRE_BIT,
 264	MAX3421_MODE_SOFKAENAB_BIT,
 265	MAX3421_MODE_SEPIRQ_BIT,
 266	MAX3421_MODE_DELAYISO_BIT,
 267	MAX3421_MODE_DMPULLDN_BIT,
 268	MAX3421_MODE_DPPULLDN_BIT
 269};
 270
 271enum {
 272	MAX3421_HRSL_OK = 0,
 273	MAX3421_HRSL_BUSY,
 274	MAX3421_HRSL_BADREQ,
 275	MAX3421_HRSL_UNDEF,
 276	MAX3421_HRSL_NAK,
 277	MAX3421_HRSL_STALL,
 278	MAX3421_HRSL_TOGERR,
 279	MAX3421_HRSL_WRONGPID,
 280	MAX3421_HRSL_BADBC,
 281	MAX3421_HRSL_PIDERR,
 282	MAX3421_HRSL_PKTERR,
 283	MAX3421_HRSL_CRCERR,
 284	MAX3421_HRSL_KERR,
 285	MAX3421_HRSL_JERR,
 286	MAX3421_HRSL_TIMEOUT,
 287	MAX3421_HRSL_BABBLE,
 288	MAX3421_HRSL_RESULT_MASK = 0xf,
 289	MAX3421_HRSL_RCVTOGRD_BIT = 4,
 290	MAX3421_HRSL_SNDTOGRD_BIT,
 291	MAX3421_HRSL_KSTATUS_BIT,
 292	MAX3421_HRSL_JSTATUS_BIT
 293};
 294
 295/* Return same error-codes as ohci.h:cc_to_error: */
 296static const int hrsl_to_error[] = {
 297	[MAX3421_HRSL_OK] =		0,
 298	[MAX3421_HRSL_BUSY] =		-EINVAL,
 299	[MAX3421_HRSL_BADREQ] =		-EINVAL,
 300	[MAX3421_HRSL_UNDEF] =		-EINVAL,
 301	[MAX3421_HRSL_NAK] =		-EAGAIN,
 302	[MAX3421_HRSL_STALL] =		-EPIPE,
 303	[MAX3421_HRSL_TOGERR] =		-EILSEQ,
 304	[MAX3421_HRSL_WRONGPID] =	-EPROTO,
 305	[MAX3421_HRSL_BADBC] =		-EREMOTEIO,
 306	[MAX3421_HRSL_PIDERR] =		-EPROTO,
 307	[MAX3421_HRSL_PKTERR] =		-EPROTO,
 308	[MAX3421_HRSL_CRCERR] =		-EILSEQ,
 309	[MAX3421_HRSL_KERR] =		-EIO,
 310	[MAX3421_HRSL_JERR] =		-EIO,
 311	[MAX3421_HRSL_TIMEOUT] =	-ETIME,
 312	[MAX3421_HRSL_BABBLE] =		-EOVERFLOW
 313};
 314
 315/*
 316 * See http://www.beyondlogic.org/usbnutshell/usb4.shtml#Control for a
 317 * reasonable overview of how control transfers use the the IN/OUT
 318 * tokens.
 319 */
 320#define MAX3421_HXFR_BULK_IN(ep)	(0x00 | (ep))	/* bulk or interrupt */
 321#define MAX3421_HXFR_SETUP		 0x10
 322#define MAX3421_HXFR_BULK_OUT(ep)	(0x20 | (ep))	/* bulk or interrupt */
 323#define MAX3421_HXFR_ISO_IN(ep)		(0x40 | (ep))
 324#define MAX3421_HXFR_ISO_OUT(ep)	(0x60 | (ep))
 325#define MAX3421_HXFR_HS_IN		 0x80		/* handshake in */
 326#define MAX3421_HXFR_HS_OUT		 0xa0		/* handshake out */
 327
 328#define field(val, bit)	((val) << (bit))
 329
 330static inline s16
 331frame_diff(u16 left, u16 right)
 332{
 333	return ((unsigned) (left - right)) % (USB_MAX_FRAME_NUMBER + 1);
 334}
 335
 336static inline struct max3421_hcd *
 337hcd_to_max3421(struct usb_hcd *hcd)
 338{
 339	return (struct max3421_hcd *) hcd->hcd_priv;
 340}
 341
 342static inline struct usb_hcd *
 343max3421_to_hcd(struct max3421_hcd *max3421_hcd)
 344{
 345	return container_of((void *) max3421_hcd, struct usb_hcd, hcd_priv);
 346}
 347
 348static u8
 349spi_rd8(struct usb_hcd *hcd, unsigned int reg)
 350{
 351	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 352	struct spi_device *spi = to_spi_device(hcd->self.controller);
 353	struct spi_transfer transfer;
 354	struct spi_message msg;
 355
 356	memset(&transfer, 0, sizeof(transfer));
 357
 358	spi_message_init(&msg);
 359
 360	max3421_hcd->tx->data[0] =
 361		(field(reg, MAX3421_SPI_REG_SHIFT) |
 362		 field(MAX3421_SPI_DIR_RD, MAX3421_SPI_DIR_SHIFT));
 363
 364	transfer.tx_buf = max3421_hcd->tx->data;
 365	transfer.rx_buf = max3421_hcd->rx->data;
 366	transfer.len = 2;
 367
 368	spi_message_add_tail(&transfer, &msg);
 369	spi_sync(spi, &msg);
 370
 371	return max3421_hcd->rx->data[1];
 372}
 373
 374static void
 375spi_wr8(struct usb_hcd *hcd, unsigned int reg, u8 val)
 376{
 377	struct spi_device *spi = to_spi_device(hcd->self.controller);
 378	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 379	struct spi_transfer transfer;
 380	struct spi_message msg;
 381
 382	memset(&transfer, 0, sizeof(transfer));
 383
 384	spi_message_init(&msg);
 385
 386	max3421_hcd->tx->data[0] =
 387		(field(reg, MAX3421_SPI_REG_SHIFT) |
 388		 field(MAX3421_SPI_DIR_WR, MAX3421_SPI_DIR_SHIFT));
 389	max3421_hcd->tx->data[1] = val;
 390
 391	transfer.tx_buf = max3421_hcd->tx->data;
 392	transfer.len = 2;
 393
 394	spi_message_add_tail(&transfer, &msg);
 395	spi_sync(spi, &msg);
 396}
 397
 398static void
 399spi_rd_buf(struct usb_hcd *hcd, unsigned int reg, void *buf, size_t len)
 400{
 401	struct spi_device *spi = to_spi_device(hcd->self.controller);
 402	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 403	struct spi_transfer transfer[2];
 404	struct spi_message msg;
 405
 406	memset(transfer, 0, sizeof(transfer));
 407
 408	spi_message_init(&msg);
 409
 410	max3421_hcd->tx->data[0] =
 411		(field(reg, MAX3421_SPI_REG_SHIFT) |
 412		 field(MAX3421_SPI_DIR_RD, MAX3421_SPI_DIR_SHIFT));
 413	transfer[0].tx_buf = max3421_hcd->tx->data;
 414	transfer[0].len = 1;
 415
 416	transfer[1].rx_buf = buf;
 417	transfer[1].len = len;
 418
 419	spi_message_add_tail(&transfer[0], &msg);
 420	spi_message_add_tail(&transfer[1], &msg);
 421	spi_sync(spi, &msg);
 422}
 423
 424static void
 425spi_wr_buf(struct usb_hcd *hcd, unsigned int reg, void *buf, size_t len)
 426{
 427	struct spi_device *spi = to_spi_device(hcd->self.controller);
 428	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 429	struct spi_transfer transfer[2];
 430	struct spi_message msg;
 431
 432	memset(transfer, 0, sizeof(transfer));
 433
 434	spi_message_init(&msg);
 435
 436	max3421_hcd->tx->data[0] =
 437		(field(reg, MAX3421_SPI_REG_SHIFT) |
 438		 field(MAX3421_SPI_DIR_WR, MAX3421_SPI_DIR_SHIFT));
 439
 440	transfer[0].tx_buf = max3421_hcd->tx->data;
 441	transfer[0].len = 1;
 442
 443	transfer[1].tx_buf = buf;
 444	transfer[1].len = len;
 445
 446	spi_message_add_tail(&transfer[0], &msg);
 447	spi_message_add_tail(&transfer[1], &msg);
 448	spi_sync(spi, &msg);
 449}
 450
 451/*
 452 * Figure out the correct setting for the LOWSPEED and HUBPRE mode
 453 * bits.  The HUBPRE bit needs to be set when MAX3421E operates at
 454 * full speed, but it's talking to a low-speed device (i.e., through a
 455 * hub).  Setting that bit ensures that every low-speed packet is
 456 * preceded by a full-speed PRE PID.  Possible configurations:
 457 *
 458 * Hub speed:	Device speed:	=>	LOWSPEED bit:	HUBPRE bit:
 459 *	FULL	FULL		=>	0		0
 460 *	FULL	LOW		=>	1		1
 461 *	LOW	LOW		=>	1		0
 462 *	LOW	FULL		=>	1		0
 463 */
 464static void
 465max3421_set_speed(struct usb_hcd *hcd, struct usb_device *dev)
 466{
 467	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 468	u8 mode_lowspeed, mode_hubpre, mode = max3421_hcd->mode;
 469
 470	mode_lowspeed = BIT(MAX3421_MODE_LOWSPEED_BIT);
 471	mode_hubpre   = BIT(MAX3421_MODE_HUBPRE_BIT);
 472	if (max3421_hcd->port_status & USB_PORT_STAT_LOW_SPEED) {
 473		mode |=  mode_lowspeed;
 474		mode &= ~mode_hubpre;
 475	} else if (dev->speed == USB_SPEED_LOW) {
 476		mode |= mode_lowspeed | mode_hubpre;
 477	} else {
 478		mode &= ~(mode_lowspeed | mode_hubpre);
 479	}
 480	if (mode != max3421_hcd->mode) {
 481		max3421_hcd->mode = mode;
 482		spi_wr8(hcd, MAX3421_REG_MODE, max3421_hcd->mode);
 483	}
 484
 485}
 486
 487/*
 488 * Caller must NOT hold HCD spinlock.
 489 */
 490static void
 491max3421_set_address(struct usb_hcd *hcd, struct usb_device *dev, int epnum,
 492		    int force_toggles)
 493{
 494	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 495	int old_epnum, same_ep, rcvtog, sndtog;
 496	struct usb_device *old_dev;
 497	u8 hctl;
 498
 499	old_dev = max3421_hcd->loaded_dev;
 500	old_epnum = max3421_hcd->loaded_epnum;
 501
 502	same_ep = (dev == old_dev && epnum == old_epnum);
 503	if (same_ep && !force_toggles)
 504		return;
 505
 506	if (old_dev && !same_ep) {
 507		/* save the old end-points toggles: */
 508		u8 hrsl = spi_rd8(hcd, MAX3421_REG_HRSL);
 509
 510		rcvtog = (hrsl >> MAX3421_HRSL_RCVTOGRD_BIT) & 1;
 511		sndtog = (hrsl >> MAX3421_HRSL_SNDTOGRD_BIT) & 1;
 512
 513		/* no locking: HCD (i.e., we) own toggles, don't we? */
 514		usb_settoggle(old_dev, old_epnum, 0, rcvtog);
 515		usb_settoggle(old_dev, old_epnum, 1, sndtog);
 516	}
 517	/* setup new endpoint's toggle bits: */
 518	rcvtog = usb_gettoggle(dev, epnum, 0);
 519	sndtog = usb_gettoggle(dev, epnum, 1);
 520	hctl = (BIT(rcvtog + MAX3421_HCTL_RCVTOG0_BIT) |
 521		BIT(sndtog + MAX3421_HCTL_SNDTOG0_BIT));
 522
 523	max3421_hcd->loaded_epnum = epnum;
 524	spi_wr8(hcd, MAX3421_REG_HCTL, hctl);
 525
 526	/*
 527	 * Note: devnum for one and the same device can change during
 528	 * address-assignment so it's best to just always load the
 529	 * address whenever the end-point changed/was forced.
 530	 */
 531	max3421_hcd->loaded_dev = dev;
 532	spi_wr8(hcd, MAX3421_REG_PERADDR, dev->devnum);
 533}
 534
 535static int
 536max3421_ctrl_setup(struct usb_hcd *hcd, struct urb *urb)
 537{
 538	spi_wr_buf(hcd, MAX3421_REG_SUDFIFO, urb->setup_packet, 8);
 539	return MAX3421_HXFR_SETUP;
 540}
 541
 542static int
 543max3421_transfer_in(struct usb_hcd *hcd, struct urb *urb)
 544{
 545	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 546	int epnum = usb_pipeendpoint(urb->pipe);
 547
 548	max3421_hcd->curr_len = 0;
 549	max3421_hcd->hien |= BIT(MAX3421_HI_RCVDAV_BIT);
 550	return MAX3421_HXFR_BULK_IN(epnum);
 551}
 552
 553static int
 554max3421_transfer_out(struct usb_hcd *hcd, struct urb *urb, int fast_retransmit)
 555{
 556	struct spi_device *spi = to_spi_device(hcd->self.controller);
 557	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 558	int epnum = usb_pipeendpoint(urb->pipe);
 559	u32 max_packet;
 560	void *src;
 561
 562	src = urb->transfer_buffer + urb->actual_length;
 563
 564	if (fast_retransmit) {
 565		if (max3421_hcd->rev == 0x12) {
 566			/* work around rev 0x12 bug: */
 567			spi_wr8(hcd, MAX3421_REG_SNDBC, 0);
 568			spi_wr8(hcd, MAX3421_REG_SNDFIFO, ((u8 *) src)[0]);
 569			spi_wr8(hcd, MAX3421_REG_SNDBC, max3421_hcd->curr_len);
 570		}
 571		return MAX3421_HXFR_BULK_OUT(epnum);
 572	}
 573
 574	max_packet = usb_maxpacket(urb->dev, urb->pipe, 1);
 575
 576	if (max_packet > MAX3421_FIFO_SIZE) {
 577		/*
 578		 * We do not support isochronous transfers at this
 579		 * time.
 580		 */
 581		dev_err(&spi->dev,
 582			"%s: packet-size of %u too big (limit is %u bytes)",
 583			__func__, max_packet, MAX3421_FIFO_SIZE);
 584		max3421_hcd->urb_done = -EMSGSIZE;
 585		return -EMSGSIZE;
 586	}
 587	max3421_hcd->curr_len = min((urb->transfer_buffer_length -
 588				     urb->actual_length), max_packet);
 589
 590	spi_wr_buf(hcd, MAX3421_REG_SNDFIFO, src, max3421_hcd->curr_len);
 591	spi_wr8(hcd, MAX3421_REG_SNDBC, max3421_hcd->curr_len);
 592	return MAX3421_HXFR_BULK_OUT(epnum);
 593}
 594
 595/*
 596 * Issue the next host-transfer command.
 597 * Caller must NOT hold HCD spinlock.
 598 */
 599static void
 600max3421_next_transfer(struct usb_hcd *hcd, int fast_retransmit)
 601{
 602	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 603	struct urb *urb = max3421_hcd->curr_urb;
 604	struct max3421_ep *max3421_ep;
 605	int cmd = -EINVAL;
 606
 607	if (!urb)
 608		return;	/* nothing to do */
 609
 610	max3421_ep = urb->ep->hcpriv;
 611
 612	switch (max3421_ep->pkt_state) {
 613	case PKT_STATE_SETUP:
 614		cmd = max3421_ctrl_setup(hcd, urb);
 615		break;
 616
 617	case PKT_STATE_TRANSFER:
 618		if (usb_urb_dir_in(urb))
 619			cmd = max3421_transfer_in(hcd, urb);
 620		else
 621			cmd = max3421_transfer_out(hcd, urb, fast_retransmit);
 622		break;
 623
 624	case PKT_STATE_TERMINATE:
 625		/*
 626		 * IN transfers are terminated with HS_OUT token,
 627		 * OUT transfers with HS_IN:
 628		 */
 629		if (usb_urb_dir_in(urb))
 630			cmd = MAX3421_HXFR_HS_OUT;
 631		else
 632			cmd = MAX3421_HXFR_HS_IN;
 633		break;
 634	}
 635
 636	if (cmd < 0)
 637		return;
 638
 639	/* issue the command and wait for host-xfer-done interrupt: */
 640
 641	spi_wr8(hcd, MAX3421_REG_HXFR, cmd);
 642	max3421_hcd->hien |= BIT(MAX3421_HI_HXFRDN_BIT);
 643}
 644
 645/*
 646 * Find the next URB to process and start its execution.
 647 *
 648 * At this time, we do not anticipate ever connecting a USB hub to the
 649 * MAX3421 chip, so at most USB device can be connected and we can use
 650 * a simplistic scheduler: at the start of a frame, schedule all
 651 * periodic transfers.  Once that is done, use the remainder of the
 652 * frame to process non-periodic (bulk & control) transfers.
 653 *
 654 * Preconditions:
 655 * o Caller must NOT hold HCD spinlock.
 656 * o max3421_hcd->curr_urb MUST BE NULL.
 657 * o MAX3421E chip must be idle.
 658 */
 659static int
 660max3421_select_and_start_urb(struct usb_hcd *hcd)
 661{
 662	struct spi_device *spi = to_spi_device(hcd->self.controller);
 663	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 664	struct urb *urb, *curr_urb = NULL;
 665	struct max3421_ep *max3421_ep;
 666	int epnum, force_toggles = 0;
 667	struct usb_host_endpoint *ep;
 668	struct list_head *pos;
 669	unsigned long flags;
 670
 671	spin_lock_irqsave(&max3421_hcd->lock, flags);
 672
 673	for (;
 674	     max3421_hcd->sched_pass < SCHED_PASS_DONE;
 675	     ++max3421_hcd->sched_pass)
 676		list_for_each(pos, &max3421_hcd->ep_list) {
 677			urb = NULL;
 678			max3421_ep = container_of(pos, struct max3421_ep,
 679						  ep_list);
 680			ep = max3421_ep->ep;
 681
 682			switch (usb_endpoint_type(&ep->desc)) {
 683			case USB_ENDPOINT_XFER_ISOC:
 684			case USB_ENDPOINT_XFER_INT:
 685				if (max3421_hcd->sched_pass !=
 686				    SCHED_PASS_PERIODIC)
 687					continue;
 688				break;
 689
 690			case USB_ENDPOINT_XFER_CONTROL:
 691			case USB_ENDPOINT_XFER_BULK:
 692				if (max3421_hcd->sched_pass !=
 693				    SCHED_PASS_NON_PERIODIC)
 694					continue;
 695				break;
 696			}
 697
 698			if (list_empty(&ep->urb_list))
 699				continue;	/* nothing to do */
 700			urb = list_first_entry(&ep->urb_list, struct urb,
 701					       urb_list);
 702			if (urb->unlinked) {
 703				dev_dbg(&spi->dev, "%s: URB %p unlinked=%d",
 704					__func__, urb, urb->unlinked);
 705				max3421_hcd->curr_urb = urb;
 706				max3421_hcd->urb_done = 1;
 707				spin_unlock_irqrestore(&max3421_hcd->lock,
 708						       flags);
 709				return 1;
 710			}
 711
 712			switch (usb_endpoint_type(&ep->desc)) {
 713			case USB_ENDPOINT_XFER_CONTROL:
 714				/*
 715				 * Allow one control transaction per
 716				 * frame per endpoint:
 717				 */
 718				if (frame_diff(max3421_ep->last_active,
 719					       max3421_hcd->frame_number) == 0)
 720					continue;
 721				break;
 722
 723			case USB_ENDPOINT_XFER_BULK:
 724				if (max3421_ep->retransmit
 725				    && (frame_diff(max3421_ep->last_active,
 726						   max3421_hcd->frame_number)
 727					== 0))
 728					/*
 729					 * We already tried this EP
 730					 * during this frame and got a
 731					 * NAK or error; wait for next frame
 732					 */
 733					continue;
 734				break;
 735
 736			case USB_ENDPOINT_XFER_ISOC:
 737			case USB_ENDPOINT_XFER_INT:
 738				if (frame_diff(max3421_hcd->frame_number,
 739					       max3421_ep->last_active)
 740				    < urb->interval)
 741					/*
 742					 * We already processed this
 743					 * end-point in the current
 744					 * frame
 745					 */
 746					continue;
 747				break;
 748			}
 749
 750			/* move current ep to tail: */
 751			list_move_tail(pos, &max3421_hcd->ep_list);
 752			curr_urb = urb;
 753			goto done;
 754		}
 755done:
 756	if (!curr_urb) {
 757		spin_unlock_irqrestore(&max3421_hcd->lock, flags);
 758		return 0;
 759	}
 760
 761	urb = max3421_hcd->curr_urb = curr_urb;
 762	epnum = usb_endpoint_num(&urb->ep->desc);
 763	if (max3421_ep->retransmit)
 764		/* restart (part of) a USB transaction: */
 765		max3421_ep->retransmit = 0;
 766	else {
 767		/* start USB transaction: */
 768		if (usb_endpoint_xfer_control(&ep->desc)) {
 769			/*
 770			 * See USB 2.0 spec section 8.6.1
 771			 * Initialization via SETUP Token:
 772			 */
 773			usb_settoggle(urb->dev, epnum, 0, 1);
 774			usb_settoggle(urb->dev, epnum, 1, 1);
 775			max3421_ep->pkt_state = PKT_STATE_SETUP;
 776			force_toggles = 1;
 777		} else
 778			max3421_ep->pkt_state = PKT_STATE_TRANSFER;
 779	}
 780
 781	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
 782
 783	max3421_ep->last_active = max3421_hcd->frame_number;
 784	max3421_set_address(hcd, urb->dev, epnum, force_toggles);
 785	max3421_set_speed(hcd, urb->dev);
 786	max3421_next_transfer(hcd, 0);
 787	return 1;
 788}
 789
 790/*
 791 * Check all endpoints for URBs that got unlinked.
 792 *
 793 * Caller must NOT hold HCD spinlock.
 794 */
 795static int
 796max3421_check_unlink(struct usb_hcd *hcd)
 797{
 798	struct spi_device *spi = to_spi_device(hcd->self.controller);
 799	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 800	struct max3421_ep *max3421_ep;
 801	struct usb_host_endpoint *ep;
 802	struct urb *urb, *next;
 803	unsigned long flags;
 804	int retval = 0;
 805
 806	spin_lock_irqsave(&max3421_hcd->lock, flags);
 807	list_for_each_entry(max3421_ep, &max3421_hcd->ep_list, ep_list) {
 808		ep = max3421_ep->ep;
 809		list_for_each_entry_safe(urb, next, &ep->urb_list, urb_list) {
 810			if (urb->unlinked) {
 811				retval = 1;
 812				dev_dbg(&spi->dev, "%s: URB %p unlinked=%d",
 813					__func__, urb, urb->unlinked);
 814				usb_hcd_unlink_urb_from_ep(hcd, urb);
 815				spin_unlock_irqrestore(&max3421_hcd->lock,
 816						       flags);
 817				usb_hcd_giveback_urb(hcd, urb, 0);
 818				spin_lock_irqsave(&max3421_hcd->lock, flags);
 819			}
 820		}
 821	}
 822	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
 823	return retval;
 824}
 825
 826/*
 827 * Caller must NOT hold HCD spinlock.
 828 */
 829static void
 830max3421_slow_retransmit(struct usb_hcd *hcd)
 831{
 832	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 833	struct urb *urb = max3421_hcd->curr_urb;
 834	struct max3421_ep *max3421_ep;
 835
 836	max3421_ep = urb->ep->hcpriv;
 837	max3421_ep->retransmit = 1;
 838	max3421_hcd->curr_urb = NULL;
 839}
 840
 841/*
 842 * Caller must NOT hold HCD spinlock.
 843 */
 844static void
 845max3421_recv_data_available(struct usb_hcd *hcd)
 846{
 847	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 848	struct urb *urb = max3421_hcd->curr_urb;
 849	size_t remaining, transfer_size;
 850	u8 rcvbc;
 851
 852	rcvbc = spi_rd8(hcd, MAX3421_REG_RCVBC);
 853
 854	if (rcvbc > MAX3421_FIFO_SIZE)
 855		rcvbc = MAX3421_FIFO_SIZE;
 856	if (urb->actual_length >= urb->transfer_buffer_length)
 857		remaining = 0;
 858	else
 859		remaining = urb->transfer_buffer_length - urb->actual_length;
 860	transfer_size = rcvbc;
 861	if (transfer_size > remaining)
 862		transfer_size = remaining;
 863	if (transfer_size > 0) {
 864		void *dst = urb->transfer_buffer + urb->actual_length;
 865
 866		spi_rd_buf(hcd, MAX3421_REG_RCVFIFO, dst, transfer_size);
 867		urb->actual_length += transfer_size;
 868		max3421_hcd->curr_len = transfer_size;
 869	}
 870
 871	/* ack the RCVDAV irq now that the FIFO has been read: */
 872	spi_wr8(hcd, MAX3421_REG_HIRQ, BIT(MAX3421_HI_RCVDAV_BIT));
 873}
 874
 875static void
 876max3421_handle_error(struct usb_hcd *hcd, u8 hrsl)
 877{
 878	struct spi_device *spi = to_spi_device(hcd->self.controller);
 879	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 880	u8 result_code = hrsl & MAX3421_HRSL_RESULT_MASK;
 881	struct urb *urb = max3421_hcd->curr_urb;
 882	struct max3421_ep *max3421_ep = urb->ep->hcpriv;
 883	int switch_sndfifo;
 884
 885	/*
 886	 * If an OUT command results in any response other than OK
 887	 * (i.e., error or NAK), we have to perform a dummy-write to
 888	 * SNDBC so the FIFO gets switched back to us.  Otherwise, we
 889	 * get out of sync with the SNDFIFO double buffer.
 890	 */
 891	switch_sndfifo = (max3421_ep->pkt_state == PKT_STATE_TRANSFER &&
 892			  usb_urb_dir_out(urb));
 893
 894	switch (result_code) {
 895	case MAX3421_HRSL_OK:
 896		return;			/* this shouldn't happen */
 897
 898	case MAX3421_HRSL_WRONGPID:	/* received wrong PID */
 899	case MAX3421_HRSL_BUSY:		/* SIE busy */
 900	case MAX3421_HRSL_BADREQ:	/* bad val in HXFR */
 901	case MAX3421_HRSL_UNDEF:	/* reserved */
 902	case MAX3421_HRSL_KERR:		/* K-state instead of response */
 903	case MAX3421_HRSL_JERR:		/* J-state instead of response */
 904		/*
 905		 * packet experienced an error that we cannot recover
 906		 * from; report error
 907		 */
 908		max3421_hcd->urb_done = hrsl_to_error[result_code];
 909		dev_dbg(&spi->dev, "%s: unexpected error HRSL=0x%02x",
 910			__func__, hrsl);
 911		break;
 912
 913	case MAX3421_HRSL_TOGERR:
 914		if (usb_urb_dir_in(urb))
 915			; /* don't do anything (device will switch toggle) */
 916		else {
 917			/* flip the send toggle bit: */
 918			int sndtog = (hrsl >> MAX3421_HRSL_SNDTOGRD_BIT) & 1;
 919
 920			sndtog ^= 1;
 921			spi_wr8(hcd, MAX3421_REG_HCTL,
 922				BIT(sndtog + MAX3421_HCTL_SNDTOG0_BIT));
 923		}
 924		/* FALL THROUGH */
 925	case MAX3421_HRSL_BADBC:	/* bad byte count */
 926	case MAX3421_HRSL_PIDERR:	/* received PID is corrupted */
 927	case MAX3421_HRSL_PKTERR:	/* packet error (stuff, EOP) */
 928	case MAX3421_HRSL_CRCERR:	/* CRC error */
 929	case MAX3421_HRSL_BABBLE:	/* device talked too long */
 930	case MAX3421_HRSL_TIMEOUT:
 931		if (max3421_ep->retries++ < USB_MAX_RETRIES)
 932			/* retry the packet again in the next frame */
 933			max3421_slow_retransmit(hcd);
 934		else {
 935			/* Based on ohci.h cc_to_err[]: */
 936			max3421_hcd->urb_done = hrsl_to_error[result_code];
 937			dev_dbg(&spi->dev, "%s: unexpected error HRSL=0x%02x",
 938				__func__, hrsl);
 939		}
 940		break;
 941
 942	case MAX3421_HRSL_STALL:
 943		dev_dbg(&spi->dev, "%s: unexpected error HRSL=0x%02x",
 944			__func__, hrsl);
 945		max3421_hcd->urb_done = hrsl_to_error[result_code];
 946		break;
 947
 948	case MAX3421_HRSL_NAK:
 949		/*
 950		 * Device wasn't ready for data or has no data
 951		 * available: retry the packet again.
 952		 */
 953		if (max3421_ep->naks++ < NAK_MAX_FAST_RETRANSMITS) {
 954			max3421_next_transfer(hcd, 1);
 955			switch_sndfifo = 0;
 956		} else
 957			max3421_slow_retransmit(hcd);
 958		break;
 959	}
 960	if (switch_sndfifo)
 961		spi_wr8(hcd, MAX3421_REG_SNDBC, 0);
 962}
 963
 964/*
 965 * Caller must NOT hold HCD spinlock.
 966 */
 967static int
 968max3421_transfer_in_done(struct usb_hcd *hcd, struct urb *urb)
 969{
 970	struct spi_device *spi = to_spi_device(hcd->self.controller);
 971	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
 972	u32 max_packet;
 973
 974	if (urb->actual_length >= urb->transfer_buffer_length)
 975		return 1;	/* read is complete, so we're done */
 976
 977	/*
 978	 * USB 2.0 Section 5.3.2 Pipes: packets must be full size
 979	 * except for last one.
 980	 */
 981	max_packet = usb_maxpacket(urb->dev, urb->pipe, 0);
 982	if (max_packet > MAX3421_FIFO_SIZE) {
 983		/*
 984		 * We do not support isochronous transfers at this
 985		 * time...
 986		 */
 987		dev_err(&spi->dev,
 988			"%s: packet-size of %u too big (limit is %u bytes)",
 989			__func__, max_packet, MAX3421_FIFO_SIZE);
 990		return -EINVAL;
 991	}
 992
 993	if (max3421_hcd->curr_len < max_packet) {
 994		if (urb->transfer_flags & URB_SHORT_NOT_OK) {
 995			/*
 996			 * remaining > 0 and received an
 997			 * unexpected partial packet ->
 998			 * error
 999			 */
1000			return -EREMOTEIO;
1001		} else
1002			/* short read, but it's OK */
1003			return 1;
1004	}
1005	return 0;	/* not done */
1006}
1007
1008/*
1009 * Caller must NOT hold HCD spinlock.
1010 */
1011static int
1012max3421_transfer_out_done(struct usb_hcd *hcd, struct urb *urb)
1013{
1014	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1015
1016	urb->actual_length += max3421_hcd->curr_len;
1017	if (urb->actual_length < urb->transfer_buffer_length)
1018		return 0;
1019	if (urb->transfer_flags & URB_ZERO_PACKET) {
1020		/*
1021		 * Some hardware needs a zero-size packet at the end
1022		 * of a bulk-out transfer if the last transfer was a
1023		 * full-sized packet (i.e., such hardware use <
1024		 * max_packet as an indicator that the end of the
1025		 * packet has been reached).
1026		 */
1027		u32 max_packet = usb_maxpacket(urb->dev, urb->pipe, 1);
1028
1029		if (max3421_hcd->curr_len == max_packet)
1030			return 0;
1031	}
1032	return 1;
1033}
1034
1035/*
1036 * Caller must NOT hold HCD spinlock.
1037 */
1038static void
1039max3421_host_transfer_done(struct usb_hcd *hcd)
1040{
1041	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1042	struct urb *urb = max3421_hcd->curr_urb;
1043	struct max3421_ep *max3421_ep;
1044	u8 result_code, hrsl;
1045	int urb_done = 0;
1046
1047	max3421_hcd->hien &= ~(BIT(MAX3421_HI_HXFRDN_BIT) |
1048			       BIT(MAX3421_HI_RCVDAV_BIT));
1049
1050	hrsl = spi_rd8(hcd, MAX3421_REG_HRSL);
1051	result_code = hrsl & MAX3421_HRSL_RESULT_MASK;
1052
1053#ifdef DEBUG
1054	++max3421_hcd->err_stat[result_code];
1055#endif
1056
1057	max3421_ep = urb->ep->hcpriv;
1058
1059	if (unlikely(result_code != MAX3421_HRSL_OK)) {
1060		max3421_handle_error(hcd, hrsl);
1061		return;
1062	}
1063
1064	max3421_ep->naks = 0;
1065	max3421_ep->retries = 0;
1066	switch (max3421_ep->pkt_state) {
1067
1068	case PKT_STATE_SETUP:
1069		if (urb->transfer_buffer_length > 0)
1070			max3421_ep->pkt_state = PKT_STATE_TRANSFER;
1071		else
1072			max3421_ep->pkt_state = PKT_STATE_TERMINATE;
1073		break;
1074
1075	case PKT_STATE_TRANSFER:
1076		if (usb_urb_dir_in(urb))
1077			urb_done = max3421_transfer_in_done(hcd, urb);
1078		else
1079			urb_done = max3421_transfer_out_done(hcd, urb);
1080		if (urb_done > 0 && usb_pipetype(urb->pipe) == PIPE_CONTROL) {
1081			/*
1082			 * We aren't really done - we still need to
1083			 * terminate the control transfer:
1084			 */
1085			max3421_hcd->urb_done = urb_done = 0;
1086			max3421_ep->pkt_state = PKT_STATE_TERMINATE;
1087		}
1088		break;
1089
1090	case PKT_STATE_TERMINATE:
1091		urb_done = 1;
1092		break;
1093	}
1094
1095	if (urb_done)
1096		max3421_hcd->urb_done = urb_done;
1097	else
1098		max3421_next_transfer(hcd, 0);
1099}
1100
1101/*
1102 * Caller must NOT hold HCD spinlock.
1103 */
1104static void
1105max3421_detect_conn(struct usb_hcd *hcd)
1106{
1107	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1108	unsigned int jk, have_conn = 0;
1109	u32 old_port_status, chg;
1110	unsigned long flags;
1111	u8 hrsl, mode;
1112
1113	hrsl = spi_rd8(hcd, MAX3421_REG_HRSL);
1114
1115	jk = ((((hrsl >> MAX3421_HRSL_JSTATUS_BIT) & 1) << 0) |
1116	      (((hrsl >> MAX3421_HRSL_KSTATUS_BIT) & 1) << 1));
1117
1118	mode = max3421_hcd->mode;
1119
1120	switch (jk) {
1121	case 0x0: /* SE0: disconnect */
1122		/*
1123		 * Turn off SOFKAENAB bit to avoid getting interrupt
1124		 * every milli-second:
1125		 */
1126		mode &= ~BIT(MAX3421_MODE_SOFKAENAB_BIT);
1127		break;
1128
1129	case 0x1: /* J=0,K=1: low-speed (in full-speed or vice versa) */
1130	case 0x2: /* J=1,K=0: full-speed (in full-speed or vice versa) */
1131		if (jk == 0x2)
1132			/* need to switch to the other speed: */
1133			mode ^= BIT(MAX3421_MODE_LOWSPEED_BIT);
1134		/* turn on SOFKAENAB bit: */
1135		mode |= BIT(MAX3421_MODE_SOFKAENAB_BIT);
1136		have_conn = 1;
1137		break;
1138
1139	case 0x3: /* illegal */
1140		break;
1141	}
1142
1143	max3421_hcd->mode = mode;
1144	spi_wr8(hcd, MAX3421_REG_MODE, max3421_hcd->mode);
1145
1146	spin_lock_irqsave(&max3421_hcd->lock, flags);
1147	old_port_status = max3421_hcd->port_status;
1148	if (have_conn)
1149		max3421_hcd->port_status |=  USB_PORT_STAT_CONNECTION;
1150	else
1151		max3421_hcd->port_status &= ~USB_PORT_STAT_CONNECTION;
1152	if (mode & BIT(MAX3421_MODE_LOWSPEED_BIT))
1153		max3421_hcd->port_status |=  USB_PORT_STAT_LOW_SPEED;
1154	else
1155		max3421_hcd->port_status &= ~USB_PORT_STAT_LOW_SPEED;
1156	chg = (old_port_status ^ max3421_hcd->port_status);
1157	max3421_hcd->port_status |= chg << 16;
1158	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1159}
1160
1161static irqreturn_t
1162max3421_irq_handler(int irq, void *dev_id)
1163{
1164	struct usb_hcd *hcd = dev_id;
1165	struct spi_device *spi = to_spi_device(hcd->self.controller);
1166	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1167
1168	if (max3421_hcd->spi_thread &&
1169	    max3421_hcd->spi_thread->state != TASK_RUNNING)
1170		wake_up_process(max3421_hcd->spi_thread);
1171	if (!test_and_set_bit(ENABLE_IRQ, &max3421_hcd->todo))
1172		disable_irq_nosync(spi->irq);
1173	return IRQ_HANDLED;
1174}
1175
1176#ifdef DEBUG
1177
1178static void
1179dump_eps(struct usb_hcd *hcd)
1180{
1181	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1182	struct max3421_ep *max3421_ep;
1183	struct usb_host_endpoint *ep;
1184	char ubuf[512], *dp, *end;
1185	unsigned long flags;
1186	struct urb *urb;
1187	int epnum, ret;
1188
1189	spin_lock_irqsave(&max3421_hcd->lock, flags);
1190	list_for_each_entry(max3421_ep, &max3421_hcd->ep_list, ep_list) {
1191		ep = max3421_ep->ep;
1192
1193		dp = ubuf;
1194		end = dp + sizeof(ubuf);
1195		*dp = '\0';
1196		list_for_each_entry(urb, &ep->urb_list, urb_list) {
1197			ret = snprintf(dp, end - dp, " %p(%d.%s %d/%d)", urb,
1198				       usb_pipetype(urb->pipe),
1199				       usb_urb_dir_in(urb) ? "IN" : "OUT",
1200				       urb->actual_length,
1201				       urb->transfer_buffer_length);
1202			if (ret < 0 || ret >= end - dp)
1203				break;	/* error or buffer full */
1204			dp += ret;
1205		}
1206
1207		epnum = usb_endpoint_num(&ep->desc);
1208		pr_info("EP%0u %u lst %04u rtr %u nak %6u rxmt %u: %s\n",
1209			epnum, max3421_ep->pkt_state, max3421_ep->last_active,
1210			max3421_ep->retries, max3421_ep->naks,
1211			max3421_ep->retransmit, ubuf);
1212	}
1213	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1214}
1215
1216#endif /* DEBUG */
1217
1218/* Return zero if no work was performed, 1 otherwise.  */
1219static int
1220max3421_handle_irqs(struct usb_hcd *hcd)
1221{
1222	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1223	u32 chg, old_port_status;
1224	unsigned long flags;
1225	u8 hirq;
1226
1227	/*
1228	 * Read and ack pending interrupts (CPU must never
1229	 * clear SNDBAV directly and RCVDAV must be cleared by
1230	 * max3421_recv_data_available()!):
1231	 */
1232	hirq = spi_rd8(hcd, MAX3421_REG_HIRQ);
1233	hirq &= max3421_hcd->hien;
1234	if (!hirq)
1235		return 0;
1236
1237	spi_wr8(hcd, MAX3421_REG_HIRQ,
1238		hirq & ~(BIT(MAX3421_HI_SNDBAV_BIT) |
1239			 BIT(MAX3421_HI_RCVDAV_BIT)));
1240
1241	if (hirq & BIT(MAX3421_HI_FRAME_BIT)) {
1242		max3421_hcd->frame_number = ((max3421_hcd->frame_number + 1)
1243					     & USB_MAX_FRAME_NUMBER);
1244		max3421_hcd->sched_pass = SCHED_PASS_PERIODIC;
1245	}
1246
1247	if (hirq & BIT(MAX3421_HI_RCVDAV_BIT))
1248		max3421_recv_data_available(hcd);
1249
1250	if (hirq & BIT(MAX3421_HI_HXFRDN_BIT))
1251		max3421_host_transfer_done(hcd);
1252
1253	if (hirq & BIT(MAX3421_HI_CONDET_BIT))
1254		max3421_detect_conn(hcd);
1255
1256	/*
1257	 * Now process interrupts that may affect HCD state
1258	 * other than the end-points:
1259	 */
1260	spin_lock_irqsave(&max3421_hcd->lock, flags);
1261
1262	old_port_status = max3421_hcd->port_status;
1263	if (hirq & BIT(MAX3421_HI_BUSEVENT_BIT)) {
1264		if (max3421_hcd->port_status & USB_PORT_STAT_RESET) {
1265			/* BUSEVENT due to completion of Bus Reset */
1266			max3421_hcd->port_status &= ~USB_PORT_STAT_RESET;
1267			max3421_hcd->port_status |=  USB_PORT_STAT_ENABLE;
1268		} else {
1269			/* BUSEVENT due to completion of Bus Resume */
1270			pr_info("%s: BUSEVENT Bus Resume Done\n", __func__);
1271		}
1272	}
1273	if (hirq & BIT(MAX3421_HI_RWU_BIT))
1274		pr_info("%s: RWU\n", __func__);
1275	if (hirq & BIT(MAX3421_HI_SUSDN_BIT))
1276		pr_info("%s: SUSDN\n", __func__);
1277
1278	chg = (old_port_status ^ max3421_hcd->port_status);
1279	max3421_hcd->port_status |= chg << 16;
1280
1281	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1282
1283#ifdef DEBUG
1284	{
1285		static unsigned long last_time;
1286		char sbuf[16 * 16], *dp, *end;
1287		int i;
1288
1289		if (time_after(jiffies, last_time + 5*HZ)) {
1290			dp = sbuf;
1291			end = sbuf + sizeof(sbuf);
1292			*dp = '\0';
1293			for (i = 0; i < 16; ++i) {
1294				int ret = snprintf(dp, end - dp, " %lu",
1295						   max3421_hcd->err_stat[i]);
1296				if (ret < 0 || ret >= end - dp)
1297					break;	/* error or buffer full */
1298				dp += ret;
1299			}
1300			pr_info("%s: hrsl_stats %s\n", __func__, sbuf);
1301			memset(max3421_hcd->err_stat, 0,
1302			       sizeof(max3421_hcd->err_stat));
1303			last_time = jiffies;
1304
1305			dump_eps(hcd);
1306		}
1307	}
1308#endif
1309	return 1;
1310}
1311
1312static int
1313max3421_reset_hcd(struct usb_hcd *hcd)
1314{
1315	struct spi_device *spi = to_spi_device(hcd->self.controller);
1316	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1317	int timeout;
1318
1319	/* perform a chip reset and wait for OSCIRQ signal to appear: */
1320	spi_wr8(hcd, MAX3421_REG_USBCTL, BIT(MAX3421_USBCTL_CHIPRES_BIT));
1321	/* clear reset: */
1322	spi_wr8(hcd, MAX3421_REG_USBCTL, 0);
1323	timeout = 1000;
1324	while (1) {
1325		if (spi_rd8(hcd, MAX3421_REG_USBIRQ)
1326		    & BIT(MAX3421_USBIRQ_OSCOKIRQ_BIT))
1327			break;
1328		if (--timeout < 0) {
1329			dev_err(&spi->dev,
1330				"timed out waiting for oscillator OK signal");
1331			return 1;
1332		}
1333		cond_resched();
1334	}
1335
1336	/*
1337	 * Turn on host mode, automatic generation of SOF packets, and
1338	 * enable pull-down registers on DM/DP:
1339	 */
1340	max3421_hcd->mode = (BIT(MAX3421_MODE_HOST_BIT) |
1341			     BIT(MAX3421_MODE_SOFKAENAB_BIT) |
1342			     BIT(MAX3421_MODE_DMPULLDN_BIT) |
1343			     BIT(MAX3421_MODE_DPPULLDN_BIT));
1344	spi_wr8(hcd, MAX3421_REG_MODE, max3421_hcd->mode);
1345
1346	/* reset frame-number: */
1347	max3421_hcd->frame_number = USB_MAX_FRAME_NUMBER;
1348	spi_wr8(hcd, MAX3421_REG_HCTL, BIT(MAX3421_HCTL_FRMRST_BIT));
1349
1350	/* sample the state of the D+ and D- lines */
1351	spi_wr8(hcd, MAX3421_REG_HCTL, BIT(MAX3421_HCTL_SAMPLEBUS_BIT));
1352	max3421_detect_conn(hcd);
1353
1354	/* enable frame, connection-detected, and bus-event interrupts: */
1355	max3421_hcd->hien = (BIT(MAX3421_HI_FRAME_BIT) |
1356			     BIT(MAX3421_HI_CONDET_BIT) |
1357			     BIT(MAX3421_HI_BUSEVENT_BIT));
1358	spi_wr8(hcd, MAX3421_REG_HIEN, max3421_hcd->hien);
1359
1360	/* enable interrupts: */
1361	spi_wr8(hcd, MAX3421_REG_CPUCTL, BIT(MAX3421_CPUCTL_IE_BIT));
1362	return 1;
1363}
1364
1365static int
1366max3421_urb_done(struct usb_hcd *hcd)
1367{
1368	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1369	unsigned long flags;
1370	struct urb *urb;
1371	int status;
1372
1373	status = max3421_hcd->urb_done;
1374	max3421_hcd->urb_done = 0;
1375	if (status > 0)
1376		status = 0;
1377	urb = max3421_hcd->curr_urb;
1378	if (urb) {
1379		max3421_hcd->curr_urb = NULL;
1380		spin_lock_irqsave(&max3421_hcd->lock, flags);
1381		usb_hcd_unlink_urb_from_ep(hcd, urb);
1382		spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1383
1384		/* must be called without the HCD spinlock: */
1385		usb_hcd_giveback_urb(hcd, urb, status);
1386	}
1387	return 1;
1388}
1389
1390static int
1391max3421_spi_thread(void *dev_id)
1392{
1393	struct usb_hcd *hcd = dev_id;
1394	struct spi_device *spi = to_spi_device(hcd->self.controller);
1395	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1396	int i, i_worked = 1;
1397
1398	/* set full-duplex SPI mode, low-active interrupt pin: */
1399	spi_wr8(hcd, MAX3421_REG_PINCTL,
1400		(BIT(MAX3421_PINCTL_FDUPSPI_BIT) |	/* full-duplex */
1401		 BIT(MAX3421_PINCTL_INTLEVEL_BIT)));	/* low-active irq */
1402
1403	while (!kthread_should_stop()) {
1404		max3421_hcd->rev = spi_rd8(hcd, MAX3421_REG_REVISION);
1405		if (max3421_hcd->rev == 0x12 || max3421_hcd->rev == 0x13)
1406			break;
1407		dev_err(&spi->dev, "bad rev 0x%02x", max3421_hcd->rev);
1408		msleep(10000);
1409	}
1410	dev_info(&spi->dev, "rev 0x%x, SPI clk %dHz, bpw %u, irq %d\n",
1411		 max3421_hcd->rev, spi->max_speed_hz, spi->bits_per_word,
1412		 spi->irq);
1413
1414	while (!kthread_should_stop()) {
1415		if (!i_worked) {
1416			/*
1417			 * We'll be waiting for wakeups from the hard
1418			 * interrupt handler, so now is a good time to
1419			 * sync our hien with the chip:
1420			 */
1421			spi_wr8(hcd, MAX3421_REG_HIEN, max3421_hcd->hien);
1422
1423			set_current_state(TASK_INTERRUPTIBLE);
1424			if (test_and_clear_bit(ENABLE_IRQ, &max3421_hcd->todo))
1425				enable_irq(spi->irq);
1426			schedule();
1427			__set_current_state(TASK_RUNNING);
1428		}
1429
1430		i_worked = 0;
1431
1432		if (max3421_hcd->urb_done)
1433			i_worked |= max3421_urb_done(hcd);
1434		else if (max3421_handle_irqs(hcd))
1435			i_worked = 1;
1436		else if (!max3421_hcd->curr_urb)
1437			i_worked |= max3421_select_and_start_urb(hcd);
1438
1439		if (test_and_clear_bit(RESET_HCD, &max3421_hcd->todo))
1440			/* reset the HCD: */
1441			i_worked |= max3421_reset_hcd(hcd);
1442		if (test_and_clear_bit(RESET_PORT, &max3421_hcd->todo)) {
1443			/* perform a USB bus reset: */
1444			spi_wr8(hcd, MAX3421_REG_HCTL,
1445				BIT(MAX3421_HCTL_BUSRST_BIT));
1446			i_worked = 1;
1447		}
1448		if (test_and_clear_bit(CHECK_UNLINK, &max3421_hcd->todo))
1449			i_worked |= max3421_check_unlink(hcd);
1450		if (test_and_clear_bit(IOPIN_UPDATE, &max3421_hcd->todo)) {
1451			/*
1452			 * IOPINS1/IOPINS2 do not auto-increment, so we can't
1453			 * use spi_wr_buf().
1454			 */
1455			for (i = 0; i < ARRAY_SIZE(max3421_hcd->iopins); ++i) {
1456				u8 val = spi_rd8(hcd, MAX3421_REG_IOPINS1);
1457
1458				val = ((val & 0xf0) |
1459				       (max3421_hcd->iopins[i] & 0x0f));
1460				spi_wr8(hcd, MAX3421_REG_IOPINS1 + i, val);
1461				max3421_hcd->iopins[i] = val;
1462			}
1463			i_worked = 1;
1464		}
1465	}
1466	set_current_state(TASK_RUNNING);
1467	dev_info(&spi->dev, "SPI thread exiting");
1468	return 0;
1469}
1470
1471static int
1472max3421_reset_port(struct usb_hcd *hcd)
1473{
1474	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1475
1476	max3421_hcd->port_status &= ~(USB_PORT_STAT_ENABLE |
1477				      USB_PORT_STAT_LOW_SPEED);
1478	max3421_hcd->port_status |= USB_PORT_STAT_RESET;
1479	set_bit(RESET_PORT, &max3421_hcd->todo);
1480	wake_up_process(max3421_hcd->spi_thread);
1481	return 0;
1482}
1483
1484static int
1485max3421_reset(struct usb_hcd *hcd)
1486{
1487	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1488
1489	hcd->self.sg_tablesize = 0;
1490	hcd->speed = HCD_USB2;
1491	hcd->self.root_hub->speed = USB_SPEED_FULL;
1492	set_bit(RESET_HCD, &max3421_hcd->todo);
1493	wake_up_process(max3421_hcd->spi_thread);
1494	return 0;
1495}
1496
1497static int
1498max3421_start(struct usb_hcd *hcd)
1499{
1500	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1501
1502	spin_lock_init(&max3421_hcd->lock);
1503	max3421_hcd->rh_state = MAX3421_RH_RUNNING;
1504
1505	INIT_LIST_HEAD(&max3421_hcd->ep_list);
1506
1507	hcd->power_budget = POWER_BUDGET;
1508	hcd->state = HC_STATE_RUNNING;
1509	hcd->uses_new_polling = 1;
1510	return 0;
1511}
1512
1513static void
1514max3421_stop(struct usb_hcd *hcd)
1515{
1516}
1517
1518static int
1519max3421_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags)
1520{
1521	struct spi_device *spi = to_spi_device(hcd->self.controller);
1522	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1523	struct max3421_ep *max3421_ep;
1524	unsigned long flags;
1525	int retval;
1526
1527	switch (usb_pipetype(urb->pipe)) {
1528	case PIPE_INTERRUPT:
1529	case PIPE_ISOCHRONOUS:
1530		if (urb->interval < 0) {
1531			dev_err(&spi->dev,
1532			  "%s: interval=%d for intr-/iso-pipe; expected > 0\n",
1533				__func__, urb->interval);
1534			return -EINVAL;
1535		}
1536	default:
1537		break;
1538	}
1539
1540	spin_lock_irqsave(&max3421_hcd->lock, flags);
1541
1542	max3421_ep = urb->ep->hcpriv;
1543	if (!max3421_ep) {
1544		/* gets freed in max3421_endpoint_disable: */
1545		max3421_ep = kzalloc(sizeof(struct max3421_ep), GFP_ATOMIC);
1546		if (!max3421_ep) {
1547			retval = -ENOMEM;
1548			goto out;
1549		}
1550		max3421_ep->ep = urb->ep;
1551		max3421_ep->last_active = max3421_hcd->frame_number;
1552		urb->ep->hcpriv = max3421_ep;
1553
1554		list_add_tail(&max3421_ep->ep_list, &max3421_hcd->ep_list);
1555	}
1556
1557	retval = usb_hcd_link_urb_to_ep(hcd, urb);
1558	if (retval == 0) {
1559		/* Since we added to the queue, restart scheduling: */
1560		max3421_hcd->sched_pass = SCHED_PASS_PERIODIC;
1561		wake_up_process(max3421_hcd->spi_thread);
1562	}
1563
1564out:
1565	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1566	return retval;
1567}
1568
1569static int
1570max3421_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
1571{
1572	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1573	unsigned long flags;
1574	int retval;
1575
1576	spin_lock_irqsave(&max3421_hcd->lock, flags);
1577
1578	/*
1579	 * This will set urb->unlinked which in turn causes the entry
1580	 * to be dropped at the next opportunity.
1581	 */
1582	retval = usb_hcd_check_unlink_urb(hcd, urb, status);
1583	if (retval == 0) {
1584		set_bit(CHECK_UNLINK, &max3421_hcd->todo);
1585		wake_up_process(max3421_hcd->spi_thread);
1586	}
1587	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1588	return retval;
1589}
1590
1591static void
1592max3421_endpoint_disable(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
1593{
1594	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1595	unsigned long flags;
1596
1597	spin_lock_irqsave(&max3421_hcd->lock, flags);
1598
1599	if (ep->hcpriv) {
1600		struct max3421_ep *max3421_ep = ep->hcpriv;
1601
1602		/* remove myself from the ep_list: */
1603		if (!list_empty(&max3421_ep->ep_list))
1604			list_del(&max3421_ep->ep_list);
1605		kfree(max3421_ep);
1606		ep->hcpriv = NULL;
1607	}
1608
1609	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1610}
1611
1612static int
1613max3421_get_frame_number(struct usb_hcd *hcd)
1614{
1615	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1616	return max3421_hcd->frame_number;
1617}
1618
1619/*
1620 * Should return a non-zero value when any port is undergoing a resume
1621 * transition while the root hub is suspended.
1622 */
1623static int
1624max3421_hub_status_data(struct usb_hcd *hcd, char *buf)
1625{
1626	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1627	unsigned long flags;
1628	int retval = 0;
1629
1630	spin_lock_irqsave(&max3421_hcd->lock, flags);
1631	if (!HCD_HW_ACCESSIBLE(hcd))
1632		goto done;
1633
1634	*buf = 0;
1635	if ((max3421_hcd->port_status & PORT_C_MASK) != 0) {
1636		*buf = (1 << 1); /* a hub over-current condition exists */
1637		dev_dbg(hcd->self.controller,
1638			"port status 0x%08x has changes\n",
1639			max3421_hcd->port_status);
1640		retval = 1;
1641		if (max3421_hcd->rh_state == MAX3421_RH_SUSPENDED)
1642			usb_hcd_resume_root_hub(hcd);
1643	}
1644done:
1645	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1646	return retval;
1647}
1648
1649static inline void
1650hub_descriptor(struct usb_hub_descriptor *desc)
1651{
1652	memset(desc, 0, sizeof(*desc));
1653	/*
1654	 * See Table 11-13: Hub Descriptor in USB 2.0 spec.
1655	 */
1656	desc->bDescriptorType = USB_DT_HUB; /* hub descriptor */
1657	desc->bDescLength = 9;
1658	desc->wHubCharacteristics = cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM |
1659						HUB_CHAR_COMMON_OCPM);
1660	desc->bNbrPorts = 1;
1661}
1662
1663/*
1664 * Set the MAX3421E general-purpose output with number PIN_NUMBER to
1665 * VALUE (0 or 1).  PIN_NUMBER may be in the range from 1-8.  For
1666 * any other value, this function acts as a no-op.
1667 */
1668static void
1669max3421_gpout_set_value(struct usb_hcd *hcd, u8 pin_number, u8 value)
1670{
1671	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1672	u8 mask, idx;
1673
1674	--pin_number;
1675	if (pin_number > 7)
1676		return;
1677
1678	mask = 1u << pin_number;
1679	idx = pin_number / 4;
1680
1681	if (value)
1682		max3421_hcd->iopins[idx] |=  mask;
1683	else
1684		max3421_hcd->iopins[idx] &= ~mask;
1685	set_bit(IOPIN_UPDATE, &max3421_hcd->todo);
1686	wake_up_process(max3421_hcd->spi_thread);
1687}
1688
1689static int
1690max3421_hub_control(struct usb_hcd *hcd, u16 type_req, u16 value, u16 index,
1691		    char *buf, u16 length)
1692{
1693	struct spi_device *spi = to_spi_device(hcd->self.controller);
1694	struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1695	struct max3421_hcd_platform_data *pdata;
1696	unsigned long flags;
1697	int retval = 0;
1698
1699	spin_lock_irqsave(&max3421_hcd->lock, flags);
1700
1701	pdata = spi->dev.platform_data;
1702
 
 
1703	switch (type_req) {
1704	case ClearHubFeature:
1705		break;
1706	case ClearPortFeature:
1707		switch (value) {
1708		case USB_PORT_FEAT_SUSPEND:
1709			break;
1710		case USB_PORT_FEAT_POWER:
1711			dev_dbg(hcd->self.controller, "power-off\n");
1712			max3421_gpout_set_value(hcd, pdata->vbus_gpout,
1713						!pdata->vbus_active_level);
1714			/* FALLS THROUGH */
1715		default:
1716			max3421_hcd->port_status &= ~(1 << value);
1717		}
1718		break;
1719	case GetHubDescriptor:
1720		hub_descriptor((struct usb_hub_descriptor *) buf);
1721		break;
1722
1723	case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
1724	case GetPortErrorCount:
1725	case SetHubDepth:
1726		/* USB3 only */
1727		goto error;
1728
1729	case GetHubStatus:
1730		*(__le32 *) buf = cpu_to_le32(0);
1731		break;
1732
1733	case GetPortStatus:
1734		if (index != 1) {
1735			retval = -EPIPE;
1736			goto error;
1737		}
1738		((__le16 *) buf)[0] = cpu_to_le16(max3421_hcd->port_status);
1739		((__le16 *) buf)[1] =
1740			cpu_to_le16(max3421_hcd->port_status >> 16);
1741		break;
1742
1743	case SetHubFeature:
1744		retval = -EPIPE;
1745		break;
1746
1747	case SetPortFeature:
1748		switch (value) {
1749		case USB_PORT_FEAT_LINK_STATE:
1750		case USB_PORT_FEAT_U1_TIMEOUT:
1751		case USB_PORT_FEAT_U2_TIMEOUT:
1752		case USB_PORT_FEAT_BH_PORT_RESET:
1753			goto error;
1754		case USB_PORT_FEAT_SUSPEND:
1755			if (max3421_hcd->active)
1756				max3421_hcd->port_status |=
1757					USB_PORT_STAT_SUSPEND;
1758			break;
1759		case USB_PORT_FEAT_POWER:
1760			dev_dbg(hcd->self.controller, "power-on\n");
1761			max3421_hcd->port_status |= USB_PORT_STAT_POWER;
1762			max3421_gpout_set_value(hcd, pdata->vbus_gpout,
1763						pdata->vbus_active_level);
1764			break;
1765		case USB_PORT_FEAT_RESET:
1766			max3421_reset_port(hcd);
1767			/* FALLS THROUGH */
1768		default:
1769			if ((max3421_hcd->port_status & USB_PORT_STAT_POWER)
1770			    != 0)
1771				max3421_hcd->port_status |= (1 << value);
1772		}
1773		break;
1774
1775	default:
1776		dev_dbg(hcd->self.controller,
1777			"hub control req%04x v%04x i%04x l%d\n",
1778			type_req, value, index, length);
1779error:		/* "protocol stall" on error */
1780		retval = -EPIPE;
1781	}
1782
1783	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1784	return retval;
1785}
1786
1787static int
1788max3421_bus_suspend(struct usb_hcd *hcd)
1789{
1790	return -1;
1791}
1792
1793static int
1794max3421_bus_resume(struct usb_hcd *hcd)
1795{
1796	return -1;
1797}
1798
1799/*
1800 * The SPI driver already takes care of DMA-mapping/unmapping, so no
1801 * reason to do it twice.
1802 */
1803static int
1804max3421_map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags)
1805{
1806	return 0;
1807}
1808
1809static void
1810max3421_unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb)
1811{
1812}
1813
1814static struct hc_driver max3421_hcd_desc = {
1815	.description =		"max3421",
1816	.product_desc =		DRIVER_DESC,
1817	.hcd_priv_size =	sizeof(struct max3421_hcd),
1818	.flags =		HCD_USB11,
1819	.reset =		max3421_reset,
1820	.start =		max3421_start,
1821	.stop =			max3421_stop,
1822	.get_frame_number =	max3421_get_frame_number,
1823	.urb_enqueue =		max3421_urb_enqueue,
1824	.urb_dequeue =		max3421_urb_dequeue,
1825	.map_urb_for_dma =	max3421_map_urb_for_dma,
1826	.unmap_urb_for_dma =	max3421_unmap_urb_for_dma,
1827	.endpoint_disable =	max3421_endpoint_disable,
1828	.hub_status_data =	max3421_hub_status_data,
1829	.hub_control =		max3421_hub_control,
1830	.bus_suspend =		max3421_bus_suspend,
1831	.bus_resume =		max3421_bus_resume,
1832};
1833
1834static int
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1835max3421_probe(struct spi_device *spi)
1836{
 
1837	struct max3421_hcd *max3421_hcd;
1838	struct usb_hcd *hcd = NULL;
 
1839	int retval = -ENOMEM;
1840
1841	if (spi_setup(spi) < 0) {
1842		dev_err(&spi->dev, "Unable to setup SPI bus");
1843		return -EFAULT;
1844	}
1845
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1846	hcd = usb_create_hcd(&max3421_hcd_desc, &spi->dev,
1847			     dev_name(&spi->dev));
1848	if (!hcd) {
1849		dev_err(&spi->dev, "failed to create HCD structure\n");
1850		goto error;
1851	}
1852	set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
1853	max3421_hcd = hcd_to_max3421(hcd);
1854	max3421_hcd->next = max3421_hcd_list;
1855	max3421_hcd_list = max3421_hcd;
1856	INIT_LIST_HEAD(&max3421_hcd->ep_list);
1857
1858	max3421_hcd->tx = kmalloc(sizeof(*max3421_hcd->tx), GFP_KERNEL);
1859	if (!max3421_hcd->tx) {
1860		dev_err(&spi->dev, "failed to kmalloc tx buffer\n");
1861		goto error;
1862	}
1863	max3421_hcd->rx = kmalloc(sizeof(*max3421_hcd->rx), GFP_KERNEL);
1864	if (!max3421_hcd->rx) {
1865		dev_err(&spi->dev, "failed to kmalloc rx buffer\n");
1866		goto error;
1867	}
1868
1869	max3421_hcd->spi_thread = kthread_run(max3421_spi_thread, hcd,
1870					      "max3421_spi_thread");
1871	if (max3421_hcd->spi_thread == ERR_PTR(-ENOMEM)) {
1872		dev_err(&spi->dev,
1873			"failed to create SPI thread (out of memory)\n");
1874		goto error;
1875	}
1876
1877	retval = usb_add_hcd(hcd, 0, 0);
1878	if (retval) {
1879		dev_err(&spi->dev, "failed to add HCD\n");
1880		goto error;
1881	}
1882
1883	retval = request_irq(spi->irq, max3421_irq_handler,
1884			     IRQF_TRIGGER_LOW, "max3421", hcd);
1885	if (retval < 0) {
1886		dev_err(&spi->dev, "failed to request irq %d\n", spi->irq);
1887		goto error;
1888	}
1889	return 0;
1890
1891error:
 
 
 
 
 
1892	if (hcd) {
1893		kfree(max3421_hcd->tx);
1894		kfree(max3421_hcd->rx);
1895		if (max3421_hcd->spi_thread)
1896			kthread_stop(max3421_hcd->spi_thread);
1897		usb_put_hcd(hcd);
1898	}
1899	return retval;
1900}
1901
1902static int
1903max3421_remove(struct spi_device *spi)
1904{
1905	struct max3421_hcd *max3421_hcd = NULL, **prev;
1906	struct usb_hcd *hcd = NULL;
1907	unsigned long flags;
1908
1909	for (prev = &max3421_hcd_list; *prev; prev = &(*prev)->next) {
1910		max3421_hcd = *prev;
1911		hcd = max3421_to_hcd(max3421_hcd);
1912		if (hcd->self.controller == &spi->dev)
1913			break;
1914	}
1915	if (!max3421_hcd) {
1916		dev_err(&spi->dev, "no MAX3421 HCD found for SPI device %p\n",
1917			spi);
1918		return -ENODEV;
1919	}
1920
1921	usb_remove_hcd(hcd);
1922
1923	spin_lock_irqsave(&max3421_hcd->lock, flags);
1924
1925	kthread_stop(max3421_hcd->spi_thread);
1926	*prev = max3421_hcd->next;
1927
1928	spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1929
1930	free_irq(spi->irq, hcd);
1931
1932	usb_put_hcd(hcd);
1933	return 0;
1934}
1935
 
 
 
 
 
 
1936static struct spi_driver max3421_driver = {
1937	.probe		= max3421_probe,
1938	.remove		= max3421_remove,
1939	.driver		= {
1940		.name	= "max3421-hcd",
 
1941	},
1942};
1943
1944module_spi_driver(max3421_driver);
1945
1946MODULE_DESCRIPTION(DRIVER_DESC);
1947MODULE_AUTHOR("David Mosberger <davidm@egauge.net>");
1948MODULE_LICENSE("GPL");