xref: /src/sys/dev/usb/ustir.c

/*	$NetBSD: ustir.c,v 1.18.2.3 2007/04/10 12:07:12 ad Exp $	*/

/*
 * Copyright (c) 2001 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by David Sainty <David.Sainty (at) dtsp.co.nz>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *        This product includes software developed by the NetBSD
 *        Foundation, Inc. and its contributors.
 * 4. Neither the name of The NetBSD Foundation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ustir.c,v 1.18.2.3 2007/04/10 12:07:12 ad Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <sys/poll.h>
#include <sys/select.h>
#include <sys/proc.h>
#include <sys/kthread.h>

#ifdef USTIR_DEBUG_IOCTLS
#include <sys/ioctl.h>
#include <dev/usb/ustir.h>
#endif

#include <dev/usb/usb.h>
#include <dev/usb/usbdevs.h>
#include <dev/usb/usbdi.h>
#include <dev/usb/usbdi_util.h>
#include <dev/usb/ustirreg.h>

#include <dev/ir/ir.h>
#include <dev/ir/irdaio.h>
#include <dev/ir/irframevar.h>
#include <dev/ir/sir.h>

#ifdef USTIR_DEBUG
#define DPRINTFN(n,x)	if (ustirdebug>(n)) logprintf x
int	ustirdebug = 0;
#else
#define DPRINTFN(n,x)
#endif

/* Max size with framing. */
#define MAX_USTIR_OUTPUT_FRAME (2*IRDA_MAX_FRAME_SIZE + IRDA_MAX_EBOFS + STIR_OUTPUT_HEADER_SIZE + 4)

#define USTIR_NSPEEDS 9
struct ustir_speedrec {
	unsigned int speed;
	unsigned int config;
};

Static struct ustir_speedrec const ustir_speeds[USTIR_NSPEEDS] = {
	{ 4000000, STIR_BRMODE_4000000 },
	{ 1152000, STIR_BRMODE_1152000 },
	{ 576000, STIR_BRMODE_576000 },
	{ 115200, STIR_BRMODE_115200 },
	{ 57600, STIR_BRMODE_57600 },
	{ 38400, STIR_BRMODE_38400 },
	{ 19200, STIR_BRMODE_19200 },
	{ 9600, STIR_BRMODE_9600 },
	{ 2400, STIR_BRMODE_2400 }
};

struct framedefn {
	unsigned int bof_count;
	u_int8_t bof_byte;

	u_int8_t esc_byte;
	u_int8_t esc_xor;

	unsigned int eof_count;
	u_int8_t eof_byte;

	unsigned int fcs_count;
	u_int32_t fcs_init;
	u_int32_t fcs_correct;

	u_int32_t (*fcs_calc)(u_int32_t, u_int8_t const*, size_t);
};

Static u_int32_t crc_ccitt_16(u_int32_t, u_int8_t const*, size_t);

struct framedefn const framedef_sir = {
	1, 0xc0,
	0x7d, 0x20,
	1, 0xc1,
	2, INITFCS, GOODFCS,
	crc_ccitt_16
};

enum framefsmstate {
	FSTATE_END_OF_FRAME,
	FSTATE_START_OF_FRAME,
	FSTATE_IN_DATA,
	FSTATE_IN_END
};

enum frameresult {
	FR_IDLE,
	FR_INPROGRESS,
	FR_FRAMEOK,
	FR_FRAMEBADFCS,
	FR_FRAMEMALFORMED,
	FR_BUFFEROVERRUN
};

struct framestate {
	struct framedefn const *definition;

	u_int8_t *buffer;
	size_t buflen;
	size_t bufindex;

	enum framefsmstate fsmstate;
	u_int escaped;
	u_int state_index;
};

#define deframe_isclear(fs) ((fs)->fsmstate == FSTATE_END_OF_FRAME)

Static void deframe_clear(struct framestate *);
Static void deframe_init(struct framestate *, struct framedefn const *,
			 u_int8_t *, size_t);
Static enum frameresult deframe_process(struct framestate *, u_int8_t const **,
					size_t *);

struct ustir_softc {
	USBBASEDEVICE		sc_dev;
	usbd_device_handle	sc_udev;
	usbd_interface_handle	sc_iface;

	u_int8_t		*sc_ur_buf; /* Unencapsulated frame */
	u_int			sc_ur_framelen;

	u_int8_t		*sc_rd_buf; /* Raw incoming data stream */
	size_t			sc_rd_index;
	int			sc_rd_addr;
	usbd_pipe_handle	sc_rd_pipe;
	usbd_xfer_handle	sc_rd_xfer;
	u_int			sc_rd_count;
	int			sc_rd_readinprogress;
	u_int			sc_rd_expectdataticks;
	u_char			sc_rd_err;
	struct framestate	sc_framestate;
	struct lwp		*sc_thread;
	struct selinfo		sc_rd_sel;

	u_int8_t		*sc_wr_buf;
	int			sc_wr_addr;
	int			sc_wr_stalewrite;
	usbd_xfer_handle	sc_wr_xfer;
	usbd_pipe_handle	sc_wr_pipe;
	struct selinfo		sc_wr_sel;

	enum {
		udir_input, /* Receiving data */
		udir_output, /* Transmitting data */
		udir_stalled, /* Error preventing data flow */
		udir_idle /* Neither receiving nor transmitting */
	} sc_direction;

	struct ustir_speedrec const *sc_speedrec;

	struct device		*sc_child;
	struct irda_params	sc_params;

	int			sc_refcnt;
	char			sc_closing;
	char			sc_dying;
};

/* True if we cannot safely read data from the device */
#define USTIR_BLOCK_RX_DATA(sc) ((sc)->sc_ur_framelen != 0)

#define USTIR_WR_TIMEOUT 200

Static int ustir_activate(device_ptr_t self, enum devact act);
Static int ustir_open(void *h, int flag, int mode, struct lwp *l);
Static int ustir_close(void *h, int flag, int mode, struct lwp *l);
Static int ustir_read(void *h, struct uio *uio, int flag);
Static int ustir_write(void *h, struct uio *uio, int flag);
Static int ustir_set_params(void *h, struct irda_params *params);
Static int ustir_get_speeds(void *h, int *speeds);
Static int ustir_get_turnarounds(void *h, int *times);
Static int ustir_poll(void *h, int events, struct lwp *l);
Static int ustir_kqfilter(void *h, struct knote *kn);

#ifdef USTIR_DEBUG_IOCTLS
Static int ustir_ioctl(void *h, u_long cmd, void *addr, int flag, struct lwp *l);
#endif

Static struct irframe_methods const ustir_methods = {
	ustir_open, ustir_close, ustir_read, ustir_write, ustir_poll,
	ustir_kqfilter, ustir_set_params, ustir_get_speeds,
	ustir_get_turnarounds,
#ifdef USTIR_DEBUG_IOCTLS
	ustir_ioctl
#endif
};

Static void ustir_rd_cb(usbd_xfer_handle, usbd_private_handle, usbd_status);
Static usbd_status ustir_start_read(struct ustir_softc *);
Static void ustir_periodic(struct ustir_softc *);
Static void ustir_thread(void *);

Static u_int32_t
crc_ccitt_16(u_int32_t crcinit, u_int8_t const *buf, size_t blen)
{
	while (blen-- > 0) {
		u_int8_t chr;
		chr = *buf++;
		crcinit = updateFCS(crcinit, chr);
	}
	return crcinit;
}

static usbd_status
ustir_read_reg(struct ustir_softc *sc, unsigned int reg, u_int8_t *data)
{
	usb_device_request_t req;

	req.bmRequestType = UT_READ_VENDOR_DEVICE;
	req.bRequest = STIR_CMD_READMULTIREG;
	USETW(req.wValue, 0);
	USETW(req.wIndex, reg);
	USETW(req.wLength, 1);

	return usbd_do_request(sc->sc_udev, &req, data);
}

static usbd_status
ustir_write_reg(struct ustir_softc *sc, unsigned int reg, u_int8_t data)
{
	usb_device_request_t req;

	req.bmRequestType = UT_WRITE_VENDOR_DEVICE;
	req.bRequest = STIR_CMD_WRITESINGLEREG;
	USETW(req.wValue, data);
	USETW(req.wIndex, reg);
	USETW(req.wLength, 0);

	return usbd_do_request(sc->sc_udev, &req, NULL);
}

#ifdef USTIR_DEBUG
static void
ustir_dumpdata(u_int8_t const *data, size_t dlen, char const *desc)
{
	size_t bdindex;
	printf("%s: (%lx)", desc, (unsigned long)dlen);
	for (bdindex = 0; bdindex < dlen; bdindex++)
		printf(" %02x", (unsigned int)data[bdindex]);
	printf("\n");
}
#endif

USB_DECLARE_DRIVER(ustir);

USB_MATCH(ustir)
{
	USB_MATCH_START(ustir, uaa);

	DPRINTFN(50,("ustir_match\n"));

	if (uaa->vendor == USB_VENDOR_SIGMATEL &&
	    uaa->product == USB_PRODUCT_SIGMATEL_IRDA)
		return UMATCH_VENDOR_PRODUCT;

	return UMATCH_NONE;
}

USB_ATTACH(ustir)
{
	USB_ATTACH_START(ustir, sc, uaa);
	usbd_device_handle dev = uaa->device;
	usbd_interface_handle iface;
	char *devinfop;
	usb_endpoint_descriptor_t *ed;
	u_int8_t epcount;
	int i;
	struct ir_attach_args ia;

	DPRINTFN(10,("ustir_attach: sc=%p\n", sc));

	devinfop = usbd_devinfo_alloc(dev, 0);
	USB_ATTACH_SETUP;
	printf("%s: %s\n", USBDEVNAME(sc->sc_dev), devinfop);
	usbd_devinfo_free(devinfop);

	if (usbd_set_config_index(dev, 0, 1)
	    || usbd_device2interface_handle(dev, 0, &iface)) {
		printf("%s: Configuration failed\n", USBDEVNAME(sc->sc_dev));
		USB_ATTACH_ERROR_RETURN;
	}

	sc->sc_udev = dev;
	sc->sc_iface = iface;

	epcount = 0;
	(void)usbd_endpoint_count(iface, &epcount);

	sc->sc_rd_addr = -1;
	sc->sc_wr_addr = -1;
	for (i = 0; i < epcount; i++) {
		ed = usbd_interface2endpoint_descriptor(iface, i);
		if (ed == NULL) {
			printf("%s: couldn't get ep %d\n",
			    USBDEVNAME(sc->sc_dev), i);
			USB_ATTACH_ERROR_RETURN;
		}
		if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_IN &&
		    UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK) {
			sc->sc_rd_addr = ed->bEndpointAddress;
		} else if (UE_GET_DIR(ed->bEndpointAddress) == UE_DIR_OUT &&
			   UE_GET_XFERTYPE(ed->bmAttributes) == UE_BULK) {
			sc->sc_wr_addr = ed->bEndpointAddress;
		}
	}
	if (sc->sc_rd_addr == -1 || sc->sc_wr_addr == -1) {
		printf("%s: missing endpoint\n", USBDEVNAME(sc->sc_dev));
		USB_ATTACH_ERROR_RETURN;
	}

	DPRINTFN(10, ("ustir_attach: %p\n", sc->sc_udev));

	usbd_add_drv_event(USB_EVENT_DRIVER_ATTACH, sc->sc_udev,
			   USBDEV(sc->sc_dev));

	ia.ia_type = IR_TYPE_IRFRAME;
	ia.ia_methods = &ustir_methods;
	ia.ia_handle = sc;

	sc->sc_child = config_found(self, &ia, ir_print);

	USB_ATTACH_SUCCESS_RETURN;
}

USB_DETACH(ustir)
{
	USB_DETACH_START(ustir, sc);
	int s;
	int rv = 0;

	DPRINTFN(0, ("ustir_detach: sc=%p flags=%d\n", sc, flags));

	sc->sc_closing = sc->sc_dying = 1;

	wakeup(&sc->sc_thread);

	while (sc->sc_thread != NULL)
		tsleep(&sc->sc_closing, PWAIT, "usircl", 0);

	/* Abort all pipes.  Causes processes waiting for transfer to wake. */
	if (sc->sc_rd_pipe != NULL) {
		usbd_abort_pipe(sc->sc_rd_pipe);
		usbd_close_pipe(sc->sc_rd_pipe);
		sc->sc_rd_pipe = NULL;
	}
	if (sc->sc_wr_pipe != NULL) {
		usbd_abort_pipe(sc->sc_wr_pipe);
		usbd_close_pipe(sc->sc_wr_pipe);
		sc->sc_wr_pipe = NULL;
	}
	wakeup(&sc->sc_ur_framelen);
	wakeup(&sc->sc_wr_buf);

	s = splusb();
	if (--sc->sc_refcnt >= 0) {
		/* Wait for processes to go away. */
		usb_detach_wait(USBDEV(sc->sc_dev));
	}
	splx(s);

	if (sc->sc_child != NULL) {
		rv = config_detach(sc->sc_child, flags);
		sc->sc_child = NULL;
	}

	usbd_add_drv_event(USB_EVENT_DRIVER_DETACH, sc->sc_udev,
			   USBDEV(sc->sc_dev));

	return rv;
}

Static void
deframe_clear(struct framestate *fstate)
{
	fstate->bufindex = 0;
	fstate->fsmstate = FSTATE_END_OF_FRAME;
	fstate->escaped = 0;
}

Static void
deframe_init(struct framestate *fstate, struct framedefn const *definition,
	     u_int8_t *buf, size_t buflen)
{
	fstate->definition = definition;
	fstate->buffer = buf;
	fstate->buflen = buflen;

	deframe_clear(fstate);
}

Static enum frameresult
deframe_process(struct framestate *fstate, u_int8_t const **bptr, size_t *blen)
{
	struct framedefn const *definition;
	u_int8_t const *cptr;
	u_int8_t escchr;
	size_t ibuflen, obufindex, obuflen;
	enum framefsmstate fsmstate;
	enum frameresult result;

	cptr = *bptr;
	fsmstate = fstate->fsmstate;
	definition = fstate->definition;
	escchr = definition->esc_byte;
	obufindex = fstate->bufindex;
	obuflen = fstate->buflen;
	ibuflen = *blen;

	while (ibuflen-- > 0) {
		u_int8_t chr;

		chr = *cptr++;

		if (fstate->escaped) {
			fstate->escaped = 0;
			chr ^= definition->esc_xor;
		} else if (chr == escchr) {
			fstate->escaped = 1;
			continue;
		}

		switch (fsmstate) {
		case FSTATE_IN_DATA:
			if (chr == definition->eof_byte) {
				fsmstate = FSTATE_IN_END;
				fstate->state_index = definition->eof_count;
				goto state_in_end;
			}
			if (obufindex >= obuflen) {
				result = FR_BUFFEROVERRUN;
				fsmstate = FSTATE_END_OF_FRAME;
				goto complete;
			}
			fstate->buffer[obufindex++] = chr;
			break;

		state_in_end:
			/* FALLTHROUGH */

		case FSTATE_IN_END:
			if (--fstate->state_index == 0) {
				u_int32_t crc;
				size_t fcslen;

				fsmstate = FSTATE_END_OF_FRAME;

				fcslen = definition->fcs_count;

				if (obufindex < fcslen) {
					result = FR_FRAMEMALFORMED;
					goto complete;
				}

				crc = definition->
					fcs_calc(definition->fcs_init,
						 fstate->buffer, obufindex);

				/* Remove check bytes from buffer length */
				obufindex -= fcslen;

				if (crc == definition->fcs_correct)
					result = FR_FRAMEOK;
				else
					result = FR_FRAMEBADFCS;

				goto complete;
			}
			break;

		case FSTATE_END_OF_FRAME:
			if (chr != definition->bof_byte)
				break;

			fsmstate = FSTATE_START_OF_FRAME;
			fstate->state_index = definition->bof_count;
			/* FALLTHROUGH */
		case FSTATE_START_OF_FRAME:
			if (--fstate->state_index == 0) {
				fsmstate = FSTATE_IN_DATA;
				obufindex = 0;
			}
			break;
		}
	}

	result = (fsmstate == FSTATE_END_OF_FRAME) ? FR_IDLE : FR_INPROGRESS;

 complete:
	fstate->bufindex = obufindex;
	fstate->fsmstate = fsmstate;
	*blen = ibuflen;

	return result;
}

/* Returns 0 if more data required, 1 if a complete frame was extracted */
static int
deframe_rd_ur(struct ustir_softc *sc)
{
	while (sc->sc_rd_index < sc->sc_rd_count) {
		u_int8_t const *buf;
		size_t buflen;
		enum frameresult fresult;

		buf = &sc->sc_rd_buf[sc->sc_rd_index];
		buflen = sc->sc_rd_count - sc->sc_rd_index;

		fresult = deframe_process(&sc->sc_framestate, &buf, &buflen);

		sc->sc_rd_index = sc->sc_rd_count - buflen;

		DPRINTFN(1,("%s: result=%d\n", __func__, (int)fresult));

		switch (fresult) {
		case FR_IDLE:
		case FR_INPROGRESS:
		case FR_FRAMEBADFCS:
		case FR_FRAMEMALFORMED:
		case FR_BUFFEROVERRUN:
			break;
		case FR_FRAMEOK:
			sc->sc_ur_framelen = sc->sc_framestate.bufindex;
			wakeup(&sc->sc_ur_framelen); /* XXX should use flag */
			selnotify(&sc->sc_rd_sel, 0);
			return 1;
		}
	}

	/* Reset indices into USB-side buffer */
	sc->sc_rd_index = sc->sc_rd_count = 0;

	return 0;
}

/*
 * Direction transitions:
 *
 * ustir_periodic() can switch the direction from:
 *
 *	output -> idle
 *	output -> stalled
 *	stalled -> idle
 *	idle -> input
 *
 * ustir_rd_cb() can switch the direction from:
 *
 *	input -> stalled
 *	input -> idle
 *
 * ustir_write() can switch the direction from:
 *
 *	idle -> output
 */
Static void
ustir_periodic(struct ustir_softc *sc)
{
	DPRINTFN(60, ("%s: direction = %d\n",
		      __func__, sc->sc_direction));

	if (sc->sc_direction == udir_output ||
	    sc->sc_direction == udir_stalled) {
		usbd_status err;
		u_int8_t regval;

		DPRINTFN(60, ("%s: reading status register\n",
			      __func__));

		err = ustir_read_reg(sc, STIR_REG_STATUS,
				     &regval);
		if (err != USBD_NORMAL_COMPLETION) {
			printf("%s: status register read failed: %s\n",
			       USBDEVNAME(sc->sc_dev),
			       usbd_errstr(err));
		} else {
			DPRINTFN(10, ("%s: status register = 0x%x\n",
				      __func__,
				      (unsigned int)regval));
			if (sc->sc_direction == udir_output &&
			    !(regval & STIR_RSTATUS_FFDIR))
				/* Output has completed */
				sc->sc_direction = udir_idle;
			if (regval & STIR_RSTATUS_FFOVER) {
				/*
				 * On an overrun the FIFO hangs, and
				 * any data bulk transfers will stall.
				 * Reset the FIFO.
				 */
				sc->sc_direction = udir_stalled;

				DPRINTFN(10, ("%s: clearing FIFO error\n",
					      __func__));

				err = ustir_write_reg(sc, STIR_REG_STATUS,
						      STIR_RSTATUS_FFCLR);
				/* XXX if we fail partway through
				 * this, we may not recover? */
				if (err == USBD_NORMAL_COMPLETION)
					err = ustir_write_reg(sc,
							      STIR_REG_STATUS,
							      0);
				if (err != USBD_NORMAL_COMPLETION) {
					printf("%s: FIFO reset failed: %s\n",
					       USBDEVNAME(sc->sc_dev),
					       usbd_errstr(err));
				} else {
					/* FIFO reset */
					sc->sc_direction = udir_idle;
				}
			}
		}
	}

	if (sc->sc_wr_stalewrite && sc->sc_direction == udir_idle) {
		/*
		 * In a stale write case, we need to check if the
		 * write has completed.  Once that has happened, the
		 * write is no longer stale.
		 *
		 * But note that we may immediately start a read poll...
		 */
		sc->sc_wr_stalewrite = 0;
		wakeup(&sc->sc_wr_buf);
	}

	if (!sc->sc_rd_readinprogress &&
	    (sc->sc_direction == udir_idle ||
	     sc->sc_direction == udir_input))
		/* Do a read poll if appropriate... */
		ustir_start_read(sc);
}

Static void
ustir_thread(void *arg)
{
	struct ustir_softc *sc = arg;

	DPRINTFN(20, ("%s: starting polling thread\n", __func__));

	while (!sc->sc_closing) {
		if (!sc->sc_rd_readinprogress && !USTIR_BLOCK_RX_DATA(sc))
			ustir_periodic(sc);

		if (!sc->sc_closing) {
			int error;
			error = tsleep(&sc->sc_thread, PWAIT,
				       "ustir", hz / 10);
			if (error == EWOULDBLOCK &&
			    sc->sc_rd_expectdataticks > 0)
				/*
				 * After a timeout decrement the tick
				 * counter within which time we expect
				 * data to arrive if we are receiving
				 * data...
				 */
				sc->sc_rd_expectdataticks--;
		}
	}

	DPRINTFN(20, ("%s: exiting polling thread\n", __func__));

	sc->sc_thread = NULL;

	wakeup(&sc->sc_closing);

	if (--sc->sc_refcnt < 0)
		usb_detach_wakeup(USBDEV(sc->sc_dev));

	kthread_exit(0);
}

Static void
ustir_rd_cb(usbd_xfer_handle xfer, usbd_private_handle priv,
	    usbd_status status)
{
	struct ustir_softc *sc = priv;
	u_int32_t size;

	DPRINTFN(60, ("%s: sc=%p\n", __func__, sc));

	/* Read is no longer in progress */
	sc->sc_rd_readinprogress = 0;

	if (status == USBD_CANCELLED || sc->sc_closing) /* this is normal */
		return;
	if (status) {
		size = 0;
		sc->sc_rd_err = 1;

		if (sc->sc_direction == udir_input ||
		    sc->sc_direction == udir_idle) {
			/*
			 * Receive error, probably need to clear error
			 * condition.
			 */
			sc->sc_direction = udir_stalled;
		}
	} else {
		usbd_get_xfer_status(xfer, NULL, NULL, &size, NULL);
	}

	sc->sc_rd_index = 0;
	sc->sc_rd_count = size;

	DPRINTFN(((size > 0 || sc->sc_rd_err != 0) ? 20 : 60),
		 ("%s: sc=%p size=%u, err=%d\n", __func__,
		  sc, size, sc->sc_rd_err));

#ifdef USTIR_DEBUG
	if (ustirdebug >= 20 && size > 0)
		ustir_dumpdata(sc->sc_rd_buf, size, __func__);
#endif

	if (!deframe_rd_ur(sc)) {
		if (!deframe_isclear(&sc->sc_framestate) && size == 0 &&
		    sc->sc_rd_expectdataticks == 0) {
			/*
			 * Expected data, but didn't get it
			 * within expected time...
			 */
			DPRINTFN(5,("%s: incoming packet timeout\n",
				    __func__));
			deframe_clear(&sc->sc_framestate);
		} else if (size > 0) {
			/*
			 * If we also received actual data, reset the
			 * data read timeout and wake up the possibly
			 * sleeping thread...
			 */
			sc->sc_rd_expectdataticks = 2;
			wakeup(&sc->sc_thread);
		}
	}

	/*
	 * Check if incoming data has stopped, or that we cannot
	 * safely read any more data.  In the case of the latter we
	 * must switch to idle so that a write will not block...
	 */
	if (sc->sc_direction == udir_input &&
	    ((size == 0 && sc->sc_rd_expectdataticks == 0) ||
	     USTIR_BLOCK_RX_DATA(sc))) {
		DPRINTFN(8,("%s: idling on packet timeout, "
			    "complete frame, or no data\n", __func__));
		sc->sc_direction = udir_idle;

		/* Wake up for possible output */
		wakeup(&sc->sc_wr_buf);
		selnotify(&sc->sc_wr_sel, 0);
	}
}

Static usbd_status
ustir_start_read(struct ustir_softc *sc)
{
	usbd_status err;

	DPRINTFN(60,("%s: sc=%p, size=%d\n", __func__, sc,
		     sc->sc_params.maxsize));

	if (sc->sc_dying)
		return USBD_IOERROR;

	if (USTIR_BLOCK_RX_DATA(sc) || deframe_rd_ur(sc)) {
		/*
		 * Can't start reading just yet.  Since we aren't
		 * going to start a read, have to switch direction to
		 * idle.
		 */
		sc->sc_direction = udir_idle;
		return USBD_NORMAL_COMPLETION;
	}

	/* Starting a read... */
	sc->sc_rd_readinprogress = 1;
	sc->sc_direction = udir_input;

	if (sc->sc_rd_err) {
		sc->sc_rd_err = 0;
		DPRINTFN(0, ("%s: clear stall\n", __func__));
		usbd_clear_endpoint_stall(sc->sc_rd_pipe);
	}

	usbd_setup_xfer(sc->sc_rd_xfer, sc->sc_rd_pipe, sc, sc->sc_rd_buf,
			sc->sc_params.maxsize,
			USBD_SHORT_XFER_OK | USBD_NO_COPY,
			USBD_NO_TIMEOUT, ustir_rd_cb);
	err = usbd_transfer(sc->sc_rd_xfer);
	if (err != USBD_IN_PROGRESS) {
		DPRINTFN(0, ("%s: err=%d\n", __func__, (int)err));
		return err;
	}
	return USBD_NORMAL_COMPLETION;
}

Static int
ustir_activate(device_ptr_t self, enum devact act)
{
	struct ustir_softc *sc = (struct ustir_softc *)self;
	int error = 0;

	switch (act) {
	case DVACT_ACTIVATE:
		return EOPNOTSUPP;

	case DVACT_DEACTIVATE:
		sc->sc_dying = 1;
		if (sc->sc_child != NULL)
			error = config_deactivate(sc->sc_child);
		break;
	}
	return error;
}

/* ARGSUSED */
Static int
ustir_open(void *h, int flag, int mode,
    struct lwp *l)
{
	struct ustir_softc *sc = h;
	int error;
	usbd_status err;

	DPRINTFN(0, ("%s: sc=%p\n", __func__, sc));

	err = usbd_open_pipe(sc->sc_iface, sc->sc_rd_addr, 0, &sc->sc_rd_pipe);
	if (err != USBD_NORMAL_COMPLETION) {
		error = EIO;
		goto bad1;
	}
	err = usbd_open_pipe(sc->sc_iface, sc->sc_wr_addr, 0, &sc->sc_wr_pipe);
	if (err != USBD_NORMAL_COMPLETION) {
		error = EIO;
		goto bad2;
	}
	sc->sc_rd_xfer = usbd_alloc_xfer(sc->sc_udev);
	if (sc->sc_rd_xfer == NULL) {
		error = ENOMEM;
		goto bad3;
	}
	sc->sc_wr_xfer = usbd_alloc_xfer(sc->sc_udev);
	if (sc->sc_wr_xfer == NULL) {
		error = ENOMEM;
		goto bad4;
	}
	sc->sc_rd_buf = usbd_alloc_buffer(sc->sc_rd_xfer,
			    IRDA_MAX_FRAME_SIZE);
	if (sc->sc_rd_buf == NULL) {
		error = ENOMEM;
		goto bad5;
	}
	sc->sc_wr_buf = usbd_alloc_buffer(sc->sc_wr_xfer,
			    IRDA_MAX_FRAME_SIZE + STIR_OUTPUT_HEADER_SIZE);
	if (sc->sc_wr_buf == NULL) {
		error = ENOMEM;
		goto bad5;
	}
	sc->sc_ur_buf = malloc(IRDA_MAX_FRAME_SIZE, M_USBDEV, M_NOWAIT);
	if (sc->sc_ur_buf == NULL) {
		error = ENOMEM;
		goto bad5;
	}

	sc->sc_rd_index = sc->sc_rd_count = 0;
	sc->sc_closing = 0;
	sc->sc_rd_readinprogress = 0;
	sc->sc_rd_expectdataticks = 0;
	sc->sc_ur_framelen = 0;
	sc->sc_rd_err = 0;
	sc->sc_wr_stalewrite = 0;
	sc->sc_speedrec = NULL;
	sc->sc_direction = udir_idle;
	sc->sc_params.speed = 0;
	sc->sc_params.ebofs = 0;
	sc->sc_params.maxsize = IRDA_MAX_FRAME_SIZE;

	deframe_init(&sc->sc_framestate, &framedef_sir, sc->sc_ur_buf,
		     IRDA_MAX_FRAME_SIZE);

	/* Increment reference for thread */
	sc->sc_refcnt++;

	error = kthread_create(PRI_NONE, false, ustir_thread, sc,
	    &sc->sc_thread, "%s", sc->sc_dev.dv_xname);
	if (error) {
		sc->sc_refcnt--;
		goto bad5;
	}

	return 0;

 bad5:
	usbd_free_xfer(sc->sc_wr_xfer);
	sc->sc_wr_xfer = NULL;
 bad4:
	usbd_free_xfer(sc->sc_rd_xfer);
	sc->sc_rd_xfer = NULL;
 bad3:
	usbd_close_pipe(sc->sc_wr_pipe);
	sc->sc_wr_pipe = NULL;
 bad2:
	usbd_close_pipe(sc->sc_rd_pipe);
	sc->sc_rd_pipe = NULL;
 bad1:
	return error;
}

/* ARGSUSED */
Static int
ustir_close(void *h, int flag, int mode,
    struct lwp *l)
{
	struct ustir_softc *sc = h;

	DPRINTFN(0, ("%s: sc=%p\n", __func__, sc));

	sc->sc_refcnt++;

	sc->sc_rd_readinprogress = 1;
	sc->sc_closing = 1;

	wakeup(&sc->sc_thread);

	while (sc->sc_thread != NULL)
		tsleep(&sc->sc_closing, PWAIT, "usircl", 0);

	if (sc->sc_rd_pipe != NULL) {
		usbd_abort_pipe(sc->sc_rd_pipe);
		usbd_close_pipe(sc->sc_rd_pipe);
		sc->sc_rd_pipe = NULL;
	}
	if (sc->sc_wr_pipe != NULL) {
		usbd_abort_pipe(sc->sc_wr_pipe);
		usbd_close_pipe(sc->sc_wr_pipe);
		sc->sc_wr_pipe = NULL;
	}
	if (sc->sc_rd_xfer != NULL) {
		usbd_free_xfer(sc->sc_rd_xfer);
		sc->sc_rd_xfer = NULL;
		sc->sc_rd_buf = NULL;
	}
	if (sc->sc_wr_xfer != NULL) {
		usbd_free_xfer(sc->sc_wr_xfer);
		sc->sc_wr_xfer = NULL;
		sc->sc_wr_buf = NULL;
	}
	if (sc->sc_ur_buf != NULL) {
		free(sc->sc_ur_buf, M_USBDEV);
		sc->sc_ur_buf = NULL;
	}

	if (--sc->sc_refcnt < 0)
		usb_detach_wakeup(USBDEV(sc->sc_dev));

	return 0;
}

/* ARGSUSED */
Static int
ustir_read(void *h, struct uio *uio, int flag)
{
	struct ustir_softc *sc = h;
	int s;
	int error;
	u_int uframelen;

	DPRINTFN(1,("%s: sc=%p\n", __func__, sc));

	if (sc->sc_dying)
		return EIO;

#ifdef DIAGNOSTIC
	if (sc->sc_rd_buf == NULL)
		return EINVAL;
#endif

	sc->sc_refcnt++;

	if (!sc->sc_rd_readinprogress && !USTIR_BLOCK_RX_DATA(sc))
		/* Possibly wake up polling thread */
		wakeup(&sc->sc_thread);

	do {
		s = splusb();
		while (sc->sc_ur_framelen == 0) {
			DPRINTFN(5,("%s: calling tsleep()\n", __func__));
			error = tsleep(&sc->sc_ur_framelen, PZERO | PCATCH,
				       "usirrd", 0);
			if (sc->sc_dying)
				error = EIO;
			if (error) {
				splx(s);
				DPRINTFN(0, ("%s: tsleep() = %d\n",
					     __func__, error));
				goto ret;
			}
		}
		splx(s);

		uframelen = sc->sc_ur_framelen;
		DPRINTFN(1,("%s: sc=%p framelen=%u, hdr=0x%02x\n",
			    __func__, sc, uframelen, sc->sc_ur_buf[0]));
		if (uframelen > uio->uio_resid)
			error = EINVAL;
		else
			error = uiomove(sc->sc_ur_buf, uframelen, uio);
		sc->sc_ur_framelen = 0;

		if (!deframe_rd_ur(sc) && uframelen > 0) {
			/*
			 * Need to wait for another read to obtain a
			 * complete frame...  If we also obtained
			 * actual data, wake up the possibly sleeping
			 * thread immediately...
			 */
			wakeup(&sc->sc_thread);
		}
	} while (uframelen == 0);

	DPRINTFN(1,("%s: return %d\n", __func__, error));

 ret:
	if (--sc->sc_refcnt < 0)
		usb_detach_wakeup(USBDEV(sc->sc_dev));
	return error;
}

/* ARGSUSED */
Static int
ustir_write(void *h, struct uio *uio, int flag)
{
	struct ustir_softc *sc = h;
	usbd_status err;
	u_int32_t wrlen;
	int error, sirlength;
	u_int8_t *wrbuf;
	int s;

	DPRINTFN(1,("%s: sc=%p\n", __func__, sc));

	if (sc->sc_dying)
		return EIO;

#ifdef DIAGNOSTIC
	if (sc->sc_wr_buf == NULL)
		return EINVAL;
#endif

	wrlen = uio->uio_resid;
	if (wrlen > sc->sc_params.maxsize)
		return EINVAL;

	sc->sc_refcnt++;

	if (!USTIR_BLOCK_RX_DATA(sc)) {
		/*
		 * If reads are not blocked, determine what action we
		 * should potentially take...
		 */
		if (sc->sc_direction == udir_output) {
			/*
			 * If the last operation was an output, wait for the
			 * polling thread to check for incoming data.
			 */
			sc->sc_wr_stalewrite = 1;
			wakeup(&sc->sc_thread);
		} else if (!sc->sc_rd_readinprogress &&
			   (sc->sc_direction == udir_idle ||
			    sc->sc_direction == udir_input)) {
			/* If idle, check for input before outputting */
			ustir_start_read(sc);
		}
	}

	s = splusb();
	while (sc->sc_wr_stalewrite ||
	       (sc->sc_direction != udir_output &&
		sc->sc_direction != udir_idle)) {
		DPRINTFN(5, ("%s: sc=%p stalewrite=%d direction=%d, "
			     "calling tsleep()\n", __func__,
			     sc, sc->sc_wr_stalewrite, sc->sc_direction));
		error = tsleep(&sc->sc_wr_buf, PZERO | PCATCH,
			       "usirwr", 0);
		if (sc->sc_dying)
			error = EIO;
		if (error) {
			splx(s);
			DPRINTFN(0, ("%s: tsleep() = %d\n", __func__,
				     error));
			goto ret;
		}
	}
	splx(s);

	wrbuf = sc->sc_wr_buf;

	/* Build header */
	wrbuf[0] = STIR_OUTPUT_HEADER_BYTE0;
	wrbuf[1] = STIR_OUTPUT_HEADER_BYTE1;

	sirlength = irda_sir_frame(&wrbuf[STIR_OUTPUT_HEADER_SIZE],
				   MAX_USTIR_OUTPUT_FRAME -
				   STIR_OUTPUT_HEADER_SIZE,
				   uio, sc->sc_params.ebofs);
	if (sirlength < 0) {
		error = -sirlength;
	} else {
		u_int32_t btlen;

		DPRINTFN(1, ("%s: transfer %u bytes\n", __func__,
			     (unsigned int)wrlen));

		wrbuf[2] = sirlength & 0xff;
		wrbuf[3] = (sirlength >> 8) & 0xff;

		btlen = STIR_OUTPUT_HEADER_SIZE + sirlength;

		sc->sc_direction = udir_output;

#ifdef USTIR_DEBUG
		if (ustirdebug >= 20)
			ustir_dumpdata(wrbuf, btlen, __func__);
#endif

		err = usbd_bulk_transfer(sc->sc_wr_xfer, sc->sc_wr_pipe,
					 USBD_FORCE_SHORT_XFER | USBD_NO_COPY,
					 USTIR_WR_TIMEOUT,
					 wrbuf, &btlen, "ustiwr");
		DPRINTFN(2, ("%s: err=%d\n", __func__, err));
		if (err != USBD_NORMAL_COMPLETION) {
			if (err == USBD_INTERRUPTED)
				error = EINTR;
			else if (err == USBD_TIMEOUT)
				error = ETIMEDOUT;
			else
				error = EIO;
		} else {
			error = 0;
		}
	}

 ret:
	if (--sc->sc_refcnt < 0)
		usb_detach_wakeup(USBDEV(sc->sc_dev));

	DPRINTFN(1,("%s: sc=%p done\n", __func__, sc));
	return error;
}

Static int
ustir_poll(void *h, int events, struct lwp *l)
{
	struct ustir_softc *sc = h;
	int revents = 0;

	DPRINTFN(1,("%s: sc=%p\n", __func__, sc));

	if (events & (POLLOUT | POLLWRNORM)) {
		if (sc->sc_direction != udir_input) {
			revents |= events & (POLLOUT | POLLWRNORM);
		} else {
			DPRINTFN(2,("%s: recording write select\n",
				    __func__));
			selrecord(l, &sc->sc_wr_sel);
		}
	}

	if (events & (POLLIN | POLLRDNORM)) {
		if (sc->sc_ur_framelen != 0) {
			DPRINTFN(2,("%s: have data\n", __func__));
			revents |= events & (POLLIN | POLLRDNORM);
		} else {
			DPRINTFN(2,("%s: recording read select\n",
				    __func__));
			selrecord(l, &sc->sc_rd_sel);
		}
	}

	return revents;
}

static void
filt_ustirrdetach(struct knote *kn)
{
	struct ustir_softc *sc = kn->kn_hook;
	int s;

	s = splusb();
	SLIST_REMOVE(&sc->sc_rd_sel.sel_klist, kn, knote, kn_selnext);
	splx(s);
}

/* ARGSUSED */
static int
filt_ustirread(struct knote *kn, long hint)
{
	struct ustir_softc *sc = kn->kn_hook;

	kn->kn_data = sc->sc_ur_framelen;
	return (kn->kn_data > 0);
}

static void
filt_ustirwdetach(struct knote *kn)
{
	struct ustir_softc *sc = kn->kn_hook;
	int s;

	s = splusb();
	SLIST_REMOVE(&sc->sc_wr_sel.sel_klist, kn, knote, kn_selnext);
	splx(s);
}

/* ARGSUSED */
static int
filt_ustirwrite(struct knote *kn, long hint)
{
	struct ustir_softc *sc = kn->kn_hook;

	kn->kn_data = 0;
	return (sc->sc_direction != udir_input);
}

static const struct filterops ustirread_filtops =
	{ 1, NULL, filt_ustirrdetach, filt_ustirread };
static const struct filterops ustirwrite_filtops =
	{ 1, NULL, filt_ustirwdetach, filt_ustirwrite };

Static int
ustir_kqfilter(void *h, struct knote *kn)
{
	struct ustir_softc *sc = h;
	struct klist *klist;
	int s;

	switch (kn->kn_filter) {
	case EVFILT_READ:
		klist = &sc->sc_rd_sel.sel_klist;
		kn->kn_fop = &ustirread_filtops;
		break;
	case EVFILT_WRITE:
		klist = &sc->sc_wr_sel.sel_klist;
		kn->kn_fop = &ustirwrite_filtops;
		break;
	default:
		return (1);
	}

	kn->kn_hook = sc;

	s = splusb();
	SLIST_INSERT_HEAD(klist, kn, kn_selnext);
	splx(s);

	return (0);
}

#ifdef USTIR_DEBUG_IOCTLS
Static int ustir_ioctl(void *h, u_long cmd, void *addr, int flag, struct lwp *l)
{
	struct ustir_softc *sc = h;
	int error;
	unsigned int regnum;
	usbd_status err;
	u_int8_t regdata;

	if (sc->sc_dying)
		return EIO;

	sc->sc_refcnt++;

	error = 0;
	switch (cmd) {
	case USTIR_READ_REGISTER:
		regnum = *(unsigned int *)addr;

		if (regnum > STIR_MAX_REG) {
			error = EINVAL;
			break;
		}

		err = ustir_read_reg(sc, regnum, &regdata);

		DPRINTFN(10, ("%s: regget(%u) = 0x%x\n", __func__,
			      regnum, (unsigned int)regdata));

		*(unsigned int *)addr = regdata;
		if (err != USBD_NORMAL_COMPLETION) {
			printf("%s: register read failed: %s\n",
			       USBDEVNAME(sc->sc_dev),
			       usbd_errstr(err));
			error = EIO;
		}
		break;

	case USTIR_WRITE_REGISTER:
		regnum = *(unsigned int *)addr;
		regdata = (regnum >> 8) & 0xff;
		regnum = regnum & 0xff;

		if (regnum > STIR_MAX_REG) {
			error = EINVAL;
			break;
		}

		DPRINTFN(10, ("%s: regset(%u, 0x%x)\n", __func__,
			      regnum, (unsigned int)regdata));

		err = ustir_write_reg(sc, regnum, regdata);
		if (err != USBD_NORMAL_COMPLETION) {
			printf("%s: register write failed: %s\n",
			       USBDEVNAME(sc->sc_dev),
			       usbd_errstr(err));
			error = EIO;
		}
		break;

	case USTIR_DEBUG_LEVEL:
#ifdef USTIR_DEBUG
		ustirdebug = *(int *)addr;
#endif
		break;

	case USTIR_DEBUG_OPERATION:
		break;

	default:
		error = EINVAL;
		break;
	}

	if (--sc->sc_refcnt < 0)
		usb_detach_wakeup(USBDEV(sc->sc_dev));

	return error;
}
#endif

Static int
ustir_set_params(void *h, struct irda_params *p)
{
	struct ustir_softc *sc = h;
	struct ustir_speedrec const *speedblk;
	int i;

	DPRINTFN(0, ("%s: sc=%p, speed=%d ebofs=%d maxsize=%d\n", __func__,
		     sc, p->speed, p->ebofs, p->maxsize));

	if (sc->sc_dying)
		return EIO;

	speedblk = NULL;

	if (sc->sc_speedrec == NULL || p->speed != sc->sc_speedrec->speed) {
		/* find speed */
		for (i = 0; i < USTIR_NSPEEDS; i++) {
			if (ustir_speeds[i].speed == p->speed) {
				speedblk = &ustir_speeds[i];
				goto found2;
			}
		}
		/* no good value found */
		return EINVAL;
	found2:
		;
	}
	if (p->maxsize != sc->sc_params.maxsize) {
		if (p->maxsize > IRDA_MAX_FRAME_SIZE)
			return EINVAL;
		sc->sc_params.maxsize = p->maxsize;
	}

	sc->sc_params = *p;

	if (speedblk != NULL) {
		usbd_status err;
		u_int8_t regmode;
		u_int8_t regbrate;

		sc->sc_speedrec = speedblk;

		regmode = STIR_BRMODE_MODEREG(speedblk->config);
		regbrate = STIR_BRMODE_BRATEREG(speedblk->config);

		/*
		 * FFSPRST must be set to enable the FIFO.
		 */
		regmode |= STIR_RMODE_FFSPRST;

		DPRINTFN(10, ("%s: setting BRATE = %x\n", __func__,
			      (unsigned int)regbrate));
		err = ustir_write_reg(sc, STIR_REG_BRATE, regbrate);
		if (err == USBD_NORMAL_COMPLETION) {
			DPRINTFN(10, ("%s: setting MODE = %x\n", __func__,
				      (unsigned int)regmode));
			err = ustir_write_reg(sc, STIR_REG_MODE, regmode);
		}
		if (err != USBD_NORMAL_COMPLETION) {
			DPRINTFN(10, ("%s: error setting register: %s\n",
				      __func__, usbd_errstr(err)));
			return EIO;
		}
	}

	return 0;
}

Static int
ustir_get_speeds(void *h, int *speeds)
{
	struct ustir_softc *sc = h;

	DPRINTFN(0, ("%s: sc=%p\n", __func__, sc));

	if (sc->sc_dying)
		return EIO;

	/* All these speeds are supported */
	*speeds = IRDA_SPEED_4000000 |
		IRDA_SPEED_1152000 |
		IRDA_SPEED_576000 |
		IRDA_SPEED_115200 |
		IRDA_SPEED_57600 |
		IRDA_SPEED_38400 |
		IRDA_SPEED_19200 |
		IRDA_SPEED_9600 |
		IRDA_SPEED_2400;

	return 0;
}

Static int
ustir_get_turnarounds(void *h, int *turnarounds)
{
	struct ustir_softc *sc = h;

	DPRINTFN(0, ("%s: sc=%p\n", __func__, sc));

	if (sc->sc_dying)
		return EIO;

	/*
	 * Documentation is on the light side with respect to
	 * turnaround time for this device.
	 */
	*turnarounds = IRDA_TURNT_10000;

	return 0;
}