move devusb to port

moved devusb to port, shifting the responsibility of how
to enable interrupts to the arch specific hci driver.

1 files changed, 1475 insertions, 0 deletions

diff --git a/sys/src/9/port/devusb.c b/sys/src/9/port/devusb.c
new file mode 100644
index 000000000..1e0ab183e
--- /dev/null
+++ b/sys/src/9/port/devusb.c
@@ -0,0 +1,1475 @@
+/*
+ * USB device driver framework.
+ *
+ * This is in charge of providing access to actual HCIs
+ * and providing I/O to the various endpoints of devices.
+ * A separate user program (usbd) is in charge of
+ * enumerating the bus, setting up endpoints and
+ * starting devices (also user programs).
+ *
+ * The interface provided is a violation of the standard:
+ * you're welcome.
+ *
+ * The interface consists of a root directory with several files
+ * plus a directory (epN.M) with two files per endpoint.
+ * A device is represented by its first endpoint, which
+ * is a control endpoint automatically allocated for each device.
+ * Device control endpoints may be used to create new endpoints.
+ * Devices corresponding to hubs may also allocate new devices,
+ * perhaps also hubs. Initially, a hub device is allocated for
+ * each controller present, to represent its root hub. Those can
+ * never be removed.
+ *
+ * All endpoints refer to the first endpoint (epN.0) of the device,
+ * which keeps per-device information, and also to the HCI used
+ * to reach them. Although all endpoints cache that information.
+ *
+ * epN.M/data files permit I/O and are considered DMEXCL.
+ * epN.M/ctl files provide status info and accept control requests.
+ *
+ * Endpoints may be given file names to be listed also at #u,
+ * for those drivers that have nothing to do after configuring the
+ * device and its endpoints.
+ *
+ * Drivers for different controllers are kept at usb[oue]hci.c
+ * It's likely we could factor out much from controllers into
+ * a generic controller driver, the problem is that details
+ * regarding how to handle toggles, tokens, Tds, etc. will
+ * get in the way. Thus, code is probably easier the way it is.
+ */
+
+#include	"u.h"
+#include	"../port/lib.h"
+#include	"mem.h"
+#include	"dat.h"
+#include	"fns.h"
+#include	"io.h"
+#include	"../port/error.h"
+#include	"../port/usb.h"
+
+typedef struct Hcitype Hcitype;
+
+enum
+{
+	/* Qid numbers */
+	Qdir = 0,		/* #u */
+	Qusbdir,			/* #u/usb */
+	Qctl,			/* #u/usb/ctl - control requests */
+
+	Qep0dir,			/* #u/usb/ep0.0 - endpoint 0 dir */
+	Qep0io,			/* #u/usb/ep0.0/data - endpoint 0 I/O */
+	Qep0ctl,		/* #u/usb/ep0.0/ctl - endpoint 0 ctl. */
+	Qep0dummy,		/* give 4 qids to each endpoint */
+
+	Qepdir = 0,		/* (qid-qep0dir)&3 is one of these */
+	Qepio,			/* to identify which file for the endpoint */
+	Qepctl,
+
+	/* ... */
+
+	/* Usb ctls. */
+	CMdebug = 0,		/* debug on|off */
+	CMdump,			/* dump (data structures for debug) */
+
+	/* Ep. ctls */
+	CMnew = 0,		/* new nb ctl|bulk|intr|iso r|w|rw (endpoint) */
+	CMnewdev,		/* newdev full|low|high portnb (allocate new devices) */
+	CMhub,			/* hub (set the device as a hub) */
+	CMspeed,		/* speed full|low|high|no */
+	CMmaxpkt,		/* maxpkt size */
+	CMntds,			/* ntds nb (max nb. of tds per µframe) */
+	CMclrhalt,		/* clrhalt (halt was cleared on endpoint) */
+	CMpollival,		/* pollival interval (interrupt/iso) */
+	CMhz,			/* hz n (samples/sec; iso) */
+	CMsamplesz,		/* samplesz n (sample size; iso) */
+	CMinfo,			/* info infostr (ke.ep info for humans) */
+	CMdetach,		/* detach (abort I/O forever on this ep). */
+	CMaddress,		/* address (address is assigned) */
+	CMdebugep,		/* debug n (set/clear debug for this ep) */
+	CMname,			/* name str (show up as #u/name as well) */
+	CMtmout,		/* timeout n (activate timeouts for ep) */
+	CMsampledelay,		/* maximum delay introduced by buffering (iso) */
+	CMpreset,		/* reset the port */
+
+	/* Hub feature selectors */
+	Rportenable	= 1,
+	Rportreset	= 4,
+
+};
+
+struct Hcitype
+{
+	char*	type;
+	int	(*reset)(Hci*);
+};
+
+#define QID(q)	((int)(q).path)
+
+static char Edetach[] = "device is detached";
+static char Enotconf[] = "endpoint not configured";
+char Estalled[] = "endpoint stalled";
+
+static Cmdtab usbctls[] =
+{
+	{CMdebug,	"debug",	2},
+	{CMdump,	"dump",		1},
+};
+
+static Cmdtab epctls[] =
+{
+	{CMnew,		"new",		4},
+	{CMnewdev,	"newdev",	3},
+	{CMhub,		"hub",		1},
+	{CMspeed,	"speed",	2},
+	{CMmaxpkt,	"maxpkt",	2},
+	{CMntds,	"ntds",		2},
+	{CMpollival,	"pollival",	2},
+	{CMsamplesz,	"samplesz",	2},
+	{CMhz,		"hz",		2},
+	{CMinfo,	"info",		0},
+	{CMdetach,	"detach",	1},
+	{CMaddress,	"address",	1},
+	{CMdebugep,	"debug",	2},
+	{CMclrhalt,	"clrhalt",	1},
+	{CMname,	"name",		2},
+	{CMtmout,	"timeout",	2},
+	{CMsampledelay,	"sampledelay",	2},
+	{CMpreset,	"reset",	1},
+};
+
+static Dirtab usbdir[] =
+{
+	"ctl",		{Qctl},		0,	0666,
+};
+
+char *usbmodename[] =
+{
+	[OREAD]	"r",
+	[OWRITE]	"w",
+	[ORDWR]	"rw",
+};
+
+static char *ttname[] =
+{
+	[Tnone]	"none",
+	[Tctl]	"control",
+	[Tiso]	"iso",
+	[Tintr]	"interrupt",
+	[Tbulk]	"bulk",
+};
+
+static char *spname[] =
+{
+	[Fullspeed]	"full",
+	[Lowspeed]	"low",
+	[Highspeed]	"high",
+	[Nospeed]	"no",
+};
+
+static int	debug;
+static Hcitype	hcitypes[Nhcis];
+static Hci*	hcis[Nhcis];
+static QLock	epslck;		/* add, del, lookup endpoints */
+static Ep*	eps[Neps];	/* all endpoints known */
+static int	epmax;		/* 1 + last endpoint index used  */
+static int	usbidgen;	/* device address generator */
+
+/*
+ * Is there something like this in a library? should it be?
+ */
+char*
+seprintdata(char *s, char *se, uchar *d, int n)
+{
+	int i, l;
+
+	s = seprint(s, se, " %#p[%d]: ", d, n);
+	l = n;
+	if(l > 10)
+		l = 10;
+	for(i=0; i<l; i++)
+		s = seprint(s, se, " %2.2ux", d[i]);
+	if(l < n)
+		s = seprint(s, se, "...");
+	return s;
+}
+
+static int
+name2speed(char *name)
+{
+	int i;
+
+	for(i = 0; i < nelem(spname); i++)
+		if(strcmp(name, spname[i]) == 0)
+			return i;
+	return Nospeed;
+}
+
+static int
+name2ttype(char *name)
+{
+	int i;
+
+	for(i = 0; i < nelem(ttname); i++)
+		if(strcmp(name, ttname[i]) == 0)
+			return i;
+	/* may be a std. USB ep. type */
+	i = strtol(name, nil, 0);
+	switch(i+1){
+	case Tctl:
+	case Tiso:
+	case Tbulk:
+	case Tintr:
+		return i+1;
+	default:
+		return Tnone;
+	}
+}
+
+static int
+name2mode(char *mode)
+{
+	int i;
+
+	for(i = 0; i < nelem(usbmodename); i++)
+		if(strcmp(mode, usbmodename[i]) == 0)
+			return i;
+	return -1;
+}
+
+static int
+qid2epidx(int q)
+{
+	q = (q-Qep0dir)/4;
+	if(q < 0 || q >= epmax || eps[q] == nil)
+		return -1;
+	return q;
+}
+
+static int
+isqtype(int q, int type)
+{
+	if(q < Qep0dir)
+		return 0;
+	q -= Qep0dir;
+	return (q & 3) == type;
+}
+
+void
+addhcitype(char* t, int (*r)(Hci*))
+{
+	static int ntype;
+
+	if(ntype == Nhcis)
+		panic("too many USB host interface types");
+	hcitypes[ntype].type = t;
+	hcitypes[ntype].reset = r;
+	ntype++;
+}
+
+static char*
+seprintep(char *s, char *se, Ep *ep, int all)
+{
+	static char* dsnames[] = { "config", "enabled", "detached", "reset" };
+	Udev *d;
+	int i;
+	int di;
+
+	d = ep->dev;
+
+	qlock(ep);
+	if(waserror()){
+		qunlock(ep);
+		nexterror();
+	}
+	di = ep->dev->nb;
+	if(all)
+		s = seprint(s, se, "dev %d ep %d ", di, ep->nb);
+	s = seprint(s, se, "%s", dsnames[ep->dev->state]);
+	s = seprint(s, se, " %s", ttname[ep->ttype]);
+	assert(ep->mode == OREAD || ep->mode == OWRITE || ep->mode == ORDWR);
+	s = seprint(s, se, " %s", usbmodename[ep->mode]);
+	s = seprint(s, se, " speed %s", spname[d->speed]);
+	s = seprint(s, se, " maxpkt %ld", ep->maxpkt);
+	s = seprint(s, se, " pollival %ld", ep->pollival);
+	s = seprint(s, se, " samplesz %ld", ep->samplesz);
+	s = seprint(s, se, " hz %ld", ep->hz);
+	s = seprint(s, se, " hub %d", ep->dev->hub);
+	s = seprint(s, se, " port %d", ep->dev->port);
+	if(ep->inuse)
+		s = seprint(s, se, " busy");
+	else
+		s = seprint(s, se, " idle");
+	if(all){
+		s = seprint(s, se, " load %uld", ep->load);
+		s = seprint(s, se, " ref %ld addr %#p", ep->ref, ep);
+		s = seprint(s, se, " idx %d", ep->idx);
+		if(ep->name != nil)
+			s = seprint(s, se, " name '%s'", ep->name);
+		if(ep->tmout != 0)
+			s = seprint(s, se, " tmout");
+		if(ep == ep->ep0){
+			s = seprint(s, se, " ctlrno %#x", ep->hp->ctlrno);
+			s = seprint(s, se, " eps:");
+			for(i = 0; i < nelem(d->eps); i++)
+				if(d->eps[i] != nil)
+					s = seprint(s, se, " ep%d.%d", di, i);
+		}
+	}
+	if(ep->info != nil)
+		s = seprint(s, se, "\n%s %s\n", ep->info, ep->hp->type);
+	else
+		s = seprint(s, se, "\n");
+	qunlock(ep);
+	poperror();
+	return s;
+}
+
+static Ep*
+epalloc(Hci *hp)
+{
+	Ep *ep;
+	int i;
+
+	ep = smalloc(sizeof(Ep));
+	ep->ref = 1;
+	qlock(&epslck);
+	for(i = 0; i < Neps; i++)
+		if(eps[i] == nil)
+			break;
+	if(i == Neps){
+		qunlock(&epslck);
+		free(ep);
+		print("usb: bug: too few endpoints.\n");
+		return nil;
+	}
+	ep->idx = i;
+	if(epmax <= i)
+		epmax = i+1;
+	eps[i] = ep;
+	ep->hp = hp;
+	ep->maxpkt = 8;
+	ep->ntds = 1;
+	ep->samplesz = ep->pollival = ep->hz = 0; /* make them void */
+	qunlock(&epslck);
+	return ep;
+}
+
+static Ep*
+getep(int i)
+{
+	Ep *ep;
+
+	if(i < 0 || i >= epmax || eps[i] == nil)
+		return nil;
+	qlock(&epslck);
+	ep = eps[i];
+	if(ep != nil)
+		incref(ep);
+	qunlock(&epslck);
+	return ep;
+}
+
+static void
+putep(Ep *ep)
+{
+	Udev *d;
+
+	if(ep != nil && decref(ep) == 0){
+		d = ep->dev;
+		deprint("usb: ep%d.%d %#p released\n", d->nb, ep->nb, ep);
+		qlock(&epslck);
+		eps[ep->idx] = nil;
+		if(ep->idx == epmax-1)
+			epmax--;
+		if(ep == ep->ep0 && ep->dev != nil && ep->dev->nb == usbidgen)
+			usbidgen--;
+		qunlock(&epslck);
+		if(d != nil){
+			qlock(ep->ep0);
+			d->eps[ep->nb] = nil;
+			qunlock(ep->ep0);
+		}
+		if(ep->ep0 != ep){
+			putep(ep->ep0);
+			ep->ep0 = nil;
+		}
+		free(ep->info);
+		free(ep->name);
+		free(ep);
+	}
+}
+
+static void
+dumpeps(void)
+{
+	int i;
+	static char buf[512];
+	char *s;
+	char *e;
+	Ep *ep;
+
+	print("usb dump eps: epmax %d Neps %d (ref=1+ for dump):\n", epmax, Neps);
+	for(i = 0; i < epmax; i++){
+		s = buf;
+		e = buf+sizeof(buf);
+		ep = getep(i);
+		if(ep != nil){
+			if(waserror()){
+				putep(ep);
+				nexterror();
+			}
+			s = seprint(s, e, "ep%d.%d ", ep->dev->nb, ep->nb);
+			seprintep(s, e, ep, 1);
+			print("%s", buf);
+			ep->hp->seprintep(buf, e, ep);
+			print("%s", buf);
+			poperror();
+			putep(ep);
+		}
+	}
+	print("usb dump hcis:\n");
+	for(i = 0; i < Nhcis; i++)
+		if(hcis[i] != nil)
+			hcis[i]->dump(hcis[i]);
+}
+
+static int
+newusbid(Hci *)
+{
+	int id;
+
+	qlock(&epslck);
+	id = ++usbidgen;
+	if(id >= 0x7F)
+		print("#u: too many device addresses; reuse them more\n");
+	qunlock(&epslck);
+	return id;
+}
+
+/*
+ * Create endpoint 0 for a new device
+ */
+static Ep*
+newdev(Hci *hp, int ishub, int isroot)
+{
+	Ep *ep;
+	Udev *d;
+
+	ep = epalloc(hp);
+	d = ep->dev = smalloc(sizeof(Udev));
+	d->nb = newusbid(hp);
+	d->eps[0] = ep;
+	ep->nb = 0;
+	ep->toggle[0] = ep->toggle[1] = 0;
+	d->ishub = ishub;
+	d->isroot = isroot;
+	if(hp->highspeed != 0)
+		d->speed = Highspeed;
+	else
+		d->speed = Fullspeed;
+	d->state = Dconfig;		/* address not yet set */
+	ep->dev = d;
+	ep->ep0 = ep;			/* no ref counted here */
+	ep->ttype = Tctl;
+	ep->tmout = Xfertmout;
+	ep->mode = ORDWR;
+	dprint("newdev %#p ep%d.%d %#p\n", d, d->nb, ep->nb, ep);
+	return ep;
+}
+
+/*
+ * Create a new endpoint for the device
+ * accessed via the given endpoint 0.
+ */
+static Ep*
+newdevep(Ep *ep, int i, int tt, int mode)
+{
+	Ep *nep;
+	Udev *d;
+
+	d = ep->dev;
+	if(d->eps[i] != nil)
+		error("endpoint already in use");
+	nep = epalloc(ep->hp);
+	incref(ep);
+	d->eps[i] = nep;
+	nep->nb = i;
+	nep->toggle[0] = nep->toggle[1] = 0;
+	nep->ep0 = ep;
+	nep->dev = ep->dev;
+	nep->mode = mode;
+	nep->ttype = tt;
+	nep->debug = ep->debug;
+	/* set defaults */
+	switch(tt){
+	case Tctl:
+		nep->tmout = Xfertmout;
+		break;
+	case Tintr:
+		nep->pollival = 10;
+		break;
+	case Tiso:
+		nep->tmout = Xfertmout;
+		nep->pollival = 10;
+		nep->samplesz = 4;
+		nep->hz = 44100;
+		break;
+	}
+	deprint("newdevep ep%d.%d %#p\n", d->nb, nep->nb, nep);
+	return ep;
+}
+
+static int
+epdataperm(int mode)
+{
+
+	switch(mode){
+	case OREAD:
+		return 0440|DMEXCL;
+		break;
+	case OWRITE:
+		return 0220|DMEXCL;
+		break;
+	default:
+		return 0660|DMEXCL;
+	}
+}
+
+static int
+usbgen(Chan *c, char *, Dirtab*, int, int s, Dir *dp)
+{
+	Qid q;
+	Dirtab *dir;
+	int perm;
+	char *se;
+	Ep *ep;
+	int nb;
+	int mode;
+
+	if(0)ddprint("usbgen q %#x s %d...", QID(c->qid), s);
+	if(s == DEVDOTDOT){
+		if(QID(c->qid) <= Qusbdir){
+			mkqid(&q, Qdir, 0, QTDIR);
+			devdir(c, q, "#u", 0, eve, 0555, dp);
+		}else{
+			mkqid(&q, Qusbdir, 0, QTDIR);
+			devdir(c, q, "usb", 0, eve, 0555, dp);
+		}
+		if(0)ddprint("ok\n");
+		return 1;
+	}
+
+	switch(QID(c->qid)){
+	case Qdir:				/* list #u */
+		if(s == 0){
+			mkqid(&q, Qusbdir, 0, QTDIR);
+			devdir(c, q, "usb", 0, eve, 0555, dp);
+			if(0)ddprint("ok\n");
+			return 1;
+		}
+		s--;
+		if(s < 0 || s >= epmax)
+			goto Fail;
+		ep = getep(s);
+		if(ep == nil || ep->name == nil){
+			if(ep != nil)
+				putep(ep);
+			if(0)ddprint("skip\n");
+			return 0;
+		}
+		if(waserror()){
+			putep(ep);
+			nexterror();
+		}
+		mkqid(&q, Qep0io+s*4, 0, QTFILE);
+		devdir(c, q, ep->name, 0, eve, epdataperm(ep->mode), dp);
+		putep(ep);
+		poperror();
+		if(0)ddprint("ok\n");
+		return 1;
+
+	case Qusbdir:				/* list #u/usb */
+	Usbdir:
+		if(s < nelem(usbdir)){
+			dir = &usbdir[s];
+			mkqid(&q, dir->qid.path, 0, QTFILE);
+			devdir(c, q, dir->name, dir->length, eve, dir->perm, dp);
+			if(0)ddprint("ok\n");
+			return 1;
+		}
+		s -= nelem(usbdir);
+		if(s < 0 || s >= epmax)
+			goto Fail;
+		ep = getep(s);
+		if(ep == nil){
+			if(0)ddprint("skip\n");
+			return 0;
+		}
+		if(waserror()){
+			putep(ep);
+			nexterror();
+		}
+		se = up->genbuf+sizeof(up->genbuf);
+		seprint(up->genbuf, se, "ep%d.%d", ep->dev->nb, ep->nb);
+		mkqid(&q, Qep0dir+4*s, 0, QTDIR);
+		putep(ep);
+		poperror();
+		devdir(c, q, up->genbuf, 0, eve, 0755, dp);
+		if(0)ddprint("ok\n");
+		return 1;
+
+	case Qctl:
+		s = 0;
+		goto Usbdir;
+
+	default:				/* list #u/usb/epN.M */
+		nb = qid2epidx(QID(c->qid));
+		ep = getep(nb);
+		if(ep == nil)
+			goto Fail;
+		mode = ep->mode;
+		putep(ep);
+		if(isqtype(QID(c->qid), Qepdir)){
+		Epdir:
+			switch(s){
+			case 0:
+				mkqid(&q, Qep0io+nb*4, 0, QTFILE);
+				perm = epdataperm(mode);
+				devdir(c, q, "data", 0, eve, perm, dp);
+				break;
+			case 1:
+				mkqid(&q, Qep0ctl+nb*4, 0, QTFILE);
+				devdir(c, q, "ctl", 0, eve, 0664, dp);
+				break;
+			default:
+				goto Fail;
+			}
+		}else if(isqtype(QID(c->qid), Qepctl)){
+			s = 1;
+			goto Epdir;
+		}else{
+			s = 0;
+			goto Epdir;
+		}
+		if(0)ddprint("ok\n");
+		return 1;
+	}
+Fail:
+	if(0)ddprint("fail\n");
+	return -1;
+}
+
+static Hci*
+hciprobe(int cardno, int ctlrno)
+{
+	Hci *hp;
+	char *type;
+	static int epnb = 1;	/* guess the endpoint nb. for the controller */
+
+	ddprint("hciprobe %d %d\n", cardno, ctlrno);
+	hp = smalloc(sizeof(Hci));
+	hp->ctlrno = ctlrno;
+	hp->tbdf = BUSUNKNOWN;
+
+	if(cardno < 0){
+		if(isaconfig("usb", ctlrno, hp) == 0){
+			free(hp);
+			return nil;
+		}
+		for(cardno = 0; cardno < Nhcis; cardno++){
+			if(hcitypes[cardno].type == nil)
+				break;
+			type = hp->type;
+			if(type==nil || *type==0)
+				type = "uhci";
+			if(cistrcmp(hcitypes[cardno].type, type) == 0)
+				break;
+		}
+	}
+
+	if(cardno >= Nhcis || hcitypes[cardno].type == nil){
+		free(hp);
+		return nil;
+	}
+	dprint("%s...", hcitypes[cardno].type);
+	if(hcitypes[cardno].reset(hp) < 0){
+		free(hp);
+		return nil;
+	}
+
+	/*
+	 * modern machines have too many usb controllers to list on
+	 * the console.
+	 */
+	dprint("#u/usb/ep%d.0: %s: port 0x%luX irq %d\n",
+		epnb, hcitypes[cardno].type, hp->port, hp->irq);
+	epnb++;
+	return hp;
+}
+
+static void
+usbreset(void)
+{
+	int cardno, ctlrno;
+	Hci *hp;
+
+	if(getconf("*nousbprobe"))
+		return;
+	dprint("usbreset\n");
+
+	for(ctlrno = 0; ctlrno < Nhcis; ctlrno++)
+		if((hp = hciprobe(-1, ctlrno)) != nil)
+			hcis[ctlrno] = hp;
+	cardno = ctlrno = 0;
+	while(cardno < Nhcis && ctlrno < Nhcis && hcitypes[cardno].type != nil)
+		if(hcis[ctlrno] != nil)
+			ctlrno++;
+		else{
+			hp = hciprobe(cardno, ctlrno);
+			if(hp == nil)
+				cardno++;
+			hcis[ctlrno++] = hp;
+		}
+	if(hcis[Nhcis-1] != nil)
+		print("usbreset: bug: Nhcis (%d) too small\n", Nhcis);
+}
+
+static void
+usbinit(void)
+{
+	Hci *hp;
+	int ctlrno;
+	Ep *d;
+	char info[40];
+
+	dprint("usbinit\n");
+	for(ctlrno = 0; ctlrno < Nhcis; ctlrno++){
+		hp = hcis[ctlrno];
+		if(hp != nil){
+			if(hp->init != nil)
+				hp->init(hp);
+			d = newdev(hp, 1, 1);		/* new root hub */
+			d->dev->state = Denabled;	/* although addr == 0 */
+			d->maxpkt = 64;
+			snprint(info, sizeof(info), "ports %d", hp->nports);
+			kstrdup(&d->info, info);
+		}
+	}
+}
+
+static Chan*
+usbattach(char *spec)
+{
+	return devattach(L'u', spec);
+}
+
+static Walkqid*
+usbwalk(Chan *c, Chan *nc, char **name, int nname)
+{
+	return devwalk(c, nc, name, nname, nil, 0, usbgen);
+}
+
+static int
+usbstat(Chan *c, uchar *db, int n)
+{
+	return devstat(c, db, n, nil, 0, usbgen);
+}
+
+/*
+ * µs for the given transfer, for bandwidth allocation.
+ * This is a very rough worst case for what 5.11.3
+ * of the usb 2.0 spec says.
+ * Also, we are using maxpkt and not actual transfer sizes.
+ * Only when we are sure we
+ * are not exceeding b/w might we consider adjusting it.
+ */
+static ulong
+usbload(int speed, int maxpkt)
+{
+	enum{ Hostns = 1000, Hubns = 333 };
+	ulong l;
+	ulong bs;
+
+	l = 0;
+	bs = 10UL * maxpkt;
+	switch(speed){
+	case Highspeed:
+		l = 55*8*2 + 2 * (3 + bs) + Hostns;
+		break;
+	case Fullspeed:
+		l = 9107 + 84 * (4 + bs) + Hostns;
+		break;
+	case Lowspeed:
+		l = 64107 + 2 * Hubns + 667 * (3 + bs) + Hostns;
+		break;
+	default:
+		print("usbload: bad speed %d\n", speed);
+		/* let it run */
+	}
+	return l / 1000UL;	/* in µs */
+}
+
+static Chan*
+usbopen(Chan *c, int omode)
+{
+	int q;
+	Ep *ep;
+	int mode;
+
+	mode = openmode(omode);
+	q = QID(c->qid);
+
+	if(q >= Qep0dir && qid2epidx(q) < 0)
+		error(Eio);
+	if(q < Qep0dir || isqtype(q, Qepctl) || isqtype(q, Qepdir))
+		return devopen(c, omode, nil, 0, usbgen);
+
+	ep = getep(qid2epidx(q));
+	if(ep == nil)
+		error(Eio);
+	deprint("usbopen q %#x fid %d omode %d\n", q, c->fid, mode);
+	if(waserror()){
+		putep(ep);
+		nexterror();
+	}
+	qlock(ep);
+	if(ep->inuse){
+		qunlock(ep);
+		error(Einuse);
+	}
+	ep->inuse = 1;
+	qunlock(ep);
+	if(waserror()){
+		ep->inuse = 0;
+		nexterror();
+	}
+	if(mode != OREAD && ep->mode == OREAD)
+		error(Eperm);
+	if(mode != OWRITE && ep->mode == OWRITE)
+		error(Eperm);
+	if(ep->ttype == Tnone)
+		error(Enotconf);
+	ep->clrhalt = 0;
+	ep->rhrepl = -1;
+	if(ep->load == 0)
+		ep->load = usbload(ep->dev->speed, ep->maxpkt);
+	ep->hp->epopen(ep);
+
+	poperror();	/* ep->inuse */
+	poperror();	/* don't putep(): ref kept for fid using the ep. */
+
+	c->mode = mode;
+	c->flag |= COPEN;
+	c->offset = 0;
+	c->aux = nil;	/* paranoia */
+	return c;
+}
+
+static void
+epclose(Ep *ep)
+{
+	qlock(ep);
+	if(waserror()){
+		qunlock(ep);
+		nexterror();
+	}
+	if(ep->inuse){
+		ep->hp->epclose(ep);
+		ep->inuse = 0;
+	}
+	qunlock(ep);
+	poperror();
+}
+
+static void
+usbclose(Chan *c)
+{
+	int q;
+	Ep *ep;
+
+	q = QID(c->qid);
+	if(q < Qep0dir || isqtype(q, Qepctl) || isqtype(q, Qepdir))
+		return;
+
+	ep = getep(qid2epidx(q));
+	if(ep == nil)
+		return;
+	deprint("usbclose q %#x fid %d ref %ld\n", q, c->fid, ep->ref);
+	if(waserror()){
+		putep(ep);
+		nexterror();
+	}
+	if(c->flag & COPEN){
+		free(c->aux);
+		c->aux = nil;
+		epclose(ep);
+		putep(ep);	/* release ref kept since usbopen */
+		c->flag &= ~COPEN;
+	}
+	poperror();
+	putep(ep);
+}
+
+static long
+ctlread(Chan *c, void *a, long n, vlong offset)
+{
+	int q;
+	char *s;
+	char *us;
+	char *se;
+	Ep *ep;
+	int i;
+
+	q = QID(c->qid);
+	us = s = smalloc(READSTR);
+	se = s + READSTR;
+	if(waserror()){
+		free(us);
+		nexterror();
+	}
+	if(q == Qctl)
+		for(i = 0; i < epmax; i++){
+			ep = getep(i);
+			if(ep != nil){
+				if(waserror()){
+					putep(ep);
+					nexterror();
+				}
+				s = seprint(s, se, "ep%d.%d ", ep->dev->nb, ep->nb);
+				s = seprintep(s, se, ep, 0);
+				poperror();
+			}
+			putep(ep);
+		}
+	else{
+		ep = getep(qid2epidx(q));
+		if(ep == nil)
+			error(Eio);
+		if(waserror()){
+			putep(ep);
+			nexterror();
+		}
+		if(c->aux != nil){
+			/* After a new endpoint request we read
+			 * the new endpoint name back.
+			 */
+			strecpy(s, se, c->aux);
+			free(c->aux);
+			c->aux = nil;
+		}else
+			seprintep(s, se, ep, 0);
+		poperror();
+		putep(ep);
+	}
+	n = readstr(offset, a, n, us);
+	poperror();
+	free(us);
+	return n;
+}
+
+/*
+ * Fake root hub emulation.
+ */
+static long
+rhubread(Ep *ep, void *a, long n)
+{
+	char *b;
+
+	if(ep->dev->isroot == 0 || ep->nb != 0 || n < 2)
+		return -1;
+	if(ep->rhrepl < 0)
+		return -1;
+
+	b = a;
+	memset(b, 0, n);
+	PUT2(b, ep->rhrepl);
+	ep->rhrepl = -1;
+	return n;
+}
+
+static long
+rhubwrite(Ep *ep, void *a, long n)
+{
+	uchar *s;
+	int cmd;
+	int feature;
+	int port;
+	Hci *hp;
+
+	if(ep->dev == nil || ep->dev->isroot == 0 || ep->nb != 0)
+		return -1;
+	if(n != Rsetuplen)
+		error("root hub is a toy hub");
+	ep->rhrepl = -1;
+	s = a;
+	if(s[Rtype] != (Rh2d|Rclass|Rother) && s[Rtype] != (Rd2h|Rclass|Rother))
+		error("root hub is a toy hub");
+	hp = ep->hp;
+	cmd = s[Rreq];
+	feature = GET2(s+Rvalue);
+	port = GET2(s+Rindex);
+	if(port < 1 || port > hp->nports)
+		error("bad hub port number");
+	switch(feature){
+	case Rportenable:
+		ep->rhrepl = hp->portenable(hp, port, cmd == Rsetfeature);
+		break;
+	case Rportreset:
+		ep->rhrepl = hp->portreset(hp, port, cmd == Rsetfeature);
+		break;
+	case Rgetstatus:
+		ep->rhrepl = hp->portstatus(hp, port);
+		break;
+	default:
+		ep->rhrepl = 0;
+	}
+	return n;
+}
+
+static long
+usbread(Chan *c, void *a, long n, vlong offset)
+{
+	int q;
+	Ep *ep;
+	int nr;
+
+	q = QID(c->qid);
+
+	if(c->qid.type == QTDIR)
+		return devdirread(c, a, n, nil, 0, usbgen);
+
+	if(q == Qctl || isqtype(q, Qepctl))
+		return ctlread(c, a, n, offset);
+
+	ep = getep(qid2epidx(q));
+	if(ep == nil)
+		error(Eio);
+	if(waserror()){
+		putep(ep);
+		nexterror();
+	}
+	if(ep->dev->state == Ddetach)
+		error(Edetach);
+	if(ep->mode == OWRITE || ep->inuse == 0)
+		error(Ebadusefd);
+	switch(ep->ttype){
+	case Tnone:
+		error("endpoint not configured");
+	case Tctl:
+		nr = rhubread(ep, a, n);
+		if(nr >= 0){
+			n = nr;
+			break;
+		}
+		/* else fall */
+	default:
+		ddeprint("\nusbread q %#x fid %d cnt %ld off %lld\n",q,c->fid,n,offset);
+		n = ep->hp->epread(ep, a, n);
+		break;
+	}
+	poperror();
+	putep(ep);
+	return n;
+}
+
+static long
+pow2(int n)
+{
+	return 1 << n;
+}
+
+static void
+setmaxpkt(Ep *ep, char* s)
+{
+	long spp;	/* samples per packet */
+
+	if(ep->dev->speed == Highspeed)
+		spp = (ep->hz * ep->pollival * ep->ntds + 7999) / 8000;
+	else
+		spp = (ep->hz * ep->pollival + 999) / 1000;
+	ep->maxpkt = spp * ep->samplesz;
+	deprint("usb: %s: setmaxpkt: hz %ld poll %ld"
+		" ntds %d %s speed -> spp %ld maxpkt %ld\n", s,
+		ep->hz, ep->pollival, ep->ntds, spname[ep->dev->speed],
+		spp, ep->maxpkt);
+	if(ep->maxpkt > 1024){
+		print("usb: %s: maxpkt %ld > 1024. truncating\n", s, ep->maxpkt);
+		ep->maxpkt = 1024;
+	}
+}
+
+/*
+ * Many endpoint ctls. simply update the portable representation
+ * of the endpoint. The actual controller driver will look
+ * at them to setup the endpoints as dictated.
+ */
+static long
+epctl(Ep *ep, Chan *c, void *a, long n)
+{
+	int i, l, mode, nb, tt;
+	char *b, *s;
+	Cmdbuf *cb;
+	Cmdtab *ct;
+	Ep *nep;
+	Udev *d;
+	static char *Info = "info ";
+
+	d = ep->dev;
+
+	cb = parsecmd(a, n);
+	if(waserror()){
+		free(cb);
+		nexterror();
+	}
+	ct = lookupcmd(cb, epctls, nelem(epctls));
+	if(ct == nil)
+		error(Ebadctl);
+	i = ct->index;
+	if(i == CMnew || i == CMspeed || i == CMhub || i == CMpreset)
+		if(ep != ep->ep0)
+			error("allowed only on a setup endpoint");
+	if(i != CMclrhalt && i != CMdetach && i != CMdebugep && i != CMname)
+		if(ep != ep->ep0 && ep->inuse != 0)
+			error("must configure before using");
+	switch(i){
+	case CMnew:
+		deprint("usb epctl %s\n", cb->f[0]);
+		nb = strtol(cb->f[1], nil, 0);
+		if(nb < 0 || nb >= Ndeveps)
+			error("bad endpoint number");
+		tt = name2ttype(cb->f[2]);
+		if(tt == Tnone)
+			error("unknown endpoint type");
+		mode = name2mode(cb->f[3]);
+		if(mode < 0)
+			error("unknown i/o mode");
+		newdevep(ep, nb, tt, mode);
+		break;
+	case CMnewdev:
+		deprint("usb epctl %s\n", cb->f[0]);
+		if(ep != ep->ep0 || d->ishub == 0)
+			error("not a hub setup endpoint");
+		l = name2speed(cb->f[1]);
+		if(l == Nospeed)
+			error("speed must be full|low|high");
+		nep = newdev(ep->hp, 0, 0);
+		nep->dev->speed = l;
+		if(nep->dev->speed  != Lowspeed)
+			nep->maxpkt = 64;	/* assume full speed */
+		nep->dev->hub = d->nb;
+		nep->dev->port = atoi(cb->f[2]);
+		/* next read request will read
+		 * the name for the new endpoint
+		 */
+		l = sizeof(up->genbuf);
+		snprint(up->genbuf, l, "ep%d.%d", nep->dev->nb, nep->nb);
+		kstrdup(&c->aux, up->genbuf);
+		break;
+	case CMhub:
+		deprint("usb epctl %s\n", cb->f[0]);
+		d->ishub = 1;
+		break;
+	case CMspeed:
+		l = name2speed(cb->f[1]);
+		deprint("usb epctl %s %d\n", cb->f[0], l);
+		if(l == Nospeed)
+			error("speed must be full|low|high");
+		qlock(ep->ep0);
+		d->speed = l;
+		qunlock(ep->ep0);
+		break;
+	case CMmaxpkt:
+		l = strtoul(cb->f[1], nil, 0);
+		deprint("usb epctl %s %d\n", cb->f[0], l);
+		if(l < 1 || l > 1024)
+			error("maxpkt not in [1:1024]");
+		qlock(ep);
+		ep->maxpkt = l;
+		qunlock(ep);
+		break;
+	case CMntds:
+		l = strtoul(cb->f[1], nil, 0);
+		deprint("usb epctl %s %d\n", cb->f[0], l);
+		if(l < 1 || l > 3)
+			error("ntds not in [1:3]");
+		qlock(ep);
+		ep->ntds = l;
+		qunlock(ep);
+		break;
+	case CMpollival:
+		if(ep->ttype != Tintr && ep->ttype != Tiso)
+			error("not an intr or iso endpoint");
+		l = strtoul(cb->f[1], nil, 0);
+		deprint("usb epctl %s %d\n", cb->f[0], l);
+		if(ep->ttype == Tiso ||
+		   (ep->ttype == Tintr && ep->dev->speed == Highspeed)){
+			if(l < 1 || l > 16)
+				error("pollival power not in [1:16]");
+			l = pow2(l-1);
+		}else
+			if(l < 1 || l > 255)
+				error("pollival not in [1:255]");
+		qlock(ep);
+		ep->pollival = l;
+		if(ep->ttype == Tiso)
+			setmaxpkt(ep, "pollival");
+		qunlock(ep);
+		break;
+	case CMsamplesz:
+		if(ep->ttype != Tiso)
+			error("not an iso endpoint");
+		l = strtoul(cb->f[1], nil, 0);
+		deprint("usb epctl %s %d\n", cb->f[0], l);
+		if(l <= 0 || l > 8)
+			error("samplesz not in [1:8]");
+		qlock(ep);
+		ep->samplesz = l;
+		setmaxpkt(ep, "samplesz");
+		qunlock(ep);
+		break;
+	case CMhz:
+		if(ep->ttype != Tiso)
+			error("not an iso endpoint");
+		l = strtoul(cb->f[1], nil, 0);
+		deprint("usb epctl %s %d\n", cb->f[0], l);
+		if(l <= 0 || l > 100000)
+			error("hz not in [1:100000]");
+		qlock(ep);
+		ep->hz = l;
+		setmaxpkt(ep, "hz");
+		qunlock(ep);
+		break;
+	case CMclrhalt:
+		qlock(ep);
+		deprint("usb epctl %s\n", cb->f[0]);
+		ep->clrhalt = 1;
+		qunlock(ep);
+		break;
+	case CMinfo:
+		deprint("usb epctl %s\n", cb->f[0]);
+		l = strlen(Info);
+		s = a;
+		if(n < l+2 || strncmp(Info, s, l) != 0)
+			error(Ebadctl);
+		if(n > 1024)
+			n = 1024;
+		b = smalloc(n);
+		memmove(b, s+l, n-l);
+		b[n-l] = 0;
+		if(b[n-l-1] == '\n')
+			b[n-l-1] = 0;
+		qlock(ep);
+		free(ep->info);
+		ep->info = b;
+		qunlock(ep);
+		break;
+	case CMaddress:
+		deprint("usb epctl %s\n", cb->f[0]);
+		ep->dev->state = Denabled;
+		break;
+	case CMdetach:
+		if(ep->dev->isroot != 0)
+			error("can't detach a root hub");
+		deprint("usb epctl %s ep%d.%d\n",
+			cb->f[0], ep->dev->nb, ep->nb);
+		ep->dev->state = Ddetach;
+		/* Release file system ref. for its endpoints */
+		for(i = 0; i < nelem(ep->dev->eps); i++)
+			putep(ep->dev->eps[i]);
+		break;
+	case CMdebugep:
+		if(strcmp(cb->f[1], "on") == 0)
+			ep->debug = 1;
+		else if(strcmp(cb->f[1], "off") == 0)
+			ep->debug = 0;
+		else
+			ep->debug = strtoul(cb->f[1], nil, 0);
+		print("usb: ep%d.%d debug %d\n",
+			ep->dev->nb, ep->nb, ep->debug);
+		break;
+	case CMname:
+		deprint("usb epctl %s %s\n", cb->f[0], cb->f[1]);
+		validname(cb->f[1], 0);
+		kstrdup(&ep->name, cb->f[1]);
+		break;
+	case CMtmout:
+		deprint("usb epctl %s\n", cb->f[0]);
+		if(ep->ttype == Tiso || ep->ttype == Tctl)
+			error("ctl ignored for this endpoint type");
+		ep->tmout = strtoul(cb->f[1], nil, 0);
+		if(ep->tmout != 0 && ep->tmout < Xfertmout)
+			ep->tmout = Xfertmout;
+		break;
+	case CMsampledelay:
+		if(ep->ttype != Tiso)
+			error("ctl ignored for this endpoint type");
+		ep->sampledelay = strtoul(cb->f[1], nil, 0);
+		break;
+	case CMpreset:
+		deprint("usb epctl %s\n", cb->f[0]);
+		if(ep->ttype != Tctl)
+			error("not a control endpoint");
+		if(ep->dev->state != Denabled)
+			error("forbidden on devices not enabled");
+		ep->dev->state = Dreset;
+		break;
+	default:
+		panic("usb: unknown epctl %d", ct->index);
+	}
+	free(cb);
+	poperror();
+	return n;
+}
+
+static long
+usbctl(void *a, long n)
+{
+	Cmdtab *ct;
+	Cmdbuf *cb;
+	Ep *ep;
+	int i;
+
+	cb = parsecmd(a, n);
+	if(waserror()){
+		free(cb);
+		nexterror();
+	}
+	ct = lookupcmd(cb, usbctls, nelem(usbctls));
+	dprint("usb ctl %s\n", cb->f[0]);
+	switch(ct->index){
+	case CMdebug:
+		if(strcmp(cb->f[1], "on") == 0)
+			debug = 1;
+		else if(strcmp(cb->f[1], "off") == 0)
+			debug = 0;
+		else
+			debug = strtol(cb->f[1], nil, 0);
+		print("usb: debug %d\n", debug);
+		for(i = 0; i < epmax; i++)
+			if((ep = getep(i)) != nil){
+				ep->hp->debug(ep->hp, debug);
+				putep(ep);
+			}
+		break;
+	case CMdump:
+		dumpeps();
+		break;
+	}
+	free(cb);
+	poperror();
+	return n;
+}
+
+static long
+ctlwrite(Chan *c, void *a, long n)
+{
+	int q;
+	Ep *ep;
+
+	q = QID(c->qid);
+	if(q == Qctl)
+		return usbctl(a, n);
+
+	ep = getep(qid2epidx(q));
+	if(ep == nil)
+		error(Eio);
+	if(waserror()){
+		putep(ep);
+		nexterror();
+	}
+	if(ep->dev->state == Ddetach)
+		error(Edetach);
+	if(isqtype(q, Qepctl) && c->aux != nil){
+		/* Be sure we don't keep a cloned ep name */
+		free(c->aux);
+		c->aux = nil;
+		error("read, not write, expected");
+	}
+	n = epctl(ep, c, a, n);
+	putep(ep);
+	poperror();
+	return n;
+}
+
+static long
+usbwrite(Chan *c, void *a, long n, vlong off)
+{
+	int nr, q;
+	Ep *ep;
+
+	if(c->qid.type == QTDIR)
+		error(Eisdir);
+
+	q = QID(c->qid);
+
+	if(q == Qctl || isqtype(q, Qepctl))
+		return ctlwrite(c, a, n);
+
+	ep = getep(qid2epidx(q));
+	if(ep == nil)
+		error(Eio);
+	if(waserror()){
+		putep(ep);
+		nexterror();
+	}
+	if(ep->dev->state == Ddetach)
+		error(Edetach);
+	if(ep->mode == OREAD || ep->inuse == 0)
+		error(Ebadusefd);
+
+	switch(ep->ttype){
+	case Tnone:
+		error("endpoint not configured");
+	case Tctl:
+		nr = rhubwrite(ep, a, n);
+		if(nr >= 0){
+			n = nr;
+			break;
+		}
+		/* else fall */
+	default:
+		ddeprint("\nusbwrite q %#x fid %d cnt %ld off %lld\n",q, c->fid, n, off);
+		ep->hp->epwrite(ep, a, n);
+	}
+	putep(ep);
+	poperror();
+	return n;
+}
+
+void
+usbshutdown(void)
+{
+	Hci *hp;
+	int i;
+
+	for(i = 0; i < Nhcis; i++){
+		hp = hcis[i];
+		if(hp == nil)
+			continue;
+		if(hp->shutdown == nil)
+			print("#u: no shutdown function for %s\n", hp->type);
+		else
+			hp->shutdown(hp);
+	}
+}
+
+Dev usbdevtab = {
+	L'u',
+	"usb",
+
+	usbreset,
+	usbinit,
+	usbshutdown,
+	usbattach,
+	usbwalk,
+	usbstat,
+	usbopen,
+	devcreate,
+	usbclose,
+	usbread,
+	devbread,
+	usbwrite,
+	devbwrite,
+	devremove,
+	devwstat,
+};