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sa1111_kbc.c revision 1.9.42.1
      1  1.9.42.1      mjf /*      $NetBSD: sa1111_kbc.c,v 1.9.42.1 2008/02/18 21:04:24 mjf Exp $ */
      2       1.1      bsh 
      3       1.1      bsh /*
      4       1.3    bjh21  * Copyright (c) 2004  Ben Harris.
      5       1.6      bsh  * Copyright (c) 2002, 2004  Genetec Corporation.  All rights reserved.
      6       1.1      bsh  * Written by Hiroyuki Bessho for Genetec Corporation.
      7       1.1      bsh  *
      8       1.1      bsh  * Redistribution and use in source and binary forms, with or without
      9       1.1      bsh  * modification, are permitted provided that the following conditions
     10       1.1      bsh  * are met:
     11       1.1      bsh  * 1. Redistributions of source code must retain the above copyright
     12       1.1      bsh  *    notice, this list of conditions and the following disclaimer.
     13       1.1      bsh  * 2. Redistributions in binary form must reproduce the above copyright
     14       1.1      bsh  *    notice, this list of conditions and the following disclaimer in the
     15       1.1      bsh  *    documentation and/or other materials provided with the distribution.
     16       1.1      bsh  * 3. The name of Genetec Corporation may not be used to endorse or
     17       1.1      bsh  *    promote products derived from this software without specific prior
     18       1.1      bsh  *    written permission.
     19       1.1      bsh  *
     20       1.1      bsh  * THIS SOFTWARE IS PROVIDED BY GENETEC CORPORATION ``AS IS'' AND
     21       1.1      bsh  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     22       1.1      bsh  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     23       1.1      bsh  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL GENETEC CORPORATION
     24       1.1      bsh  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     25       1.1      bsh  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     26       1.1      bsh  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     27       1.1      bsh  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     28       1.1      bsh  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     29       1.1      bsh  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     30       1.1      bsh  * POSSIBILITY OF SUCH DAMAGE.
     31       1.1      bsh  *
     32       1.1      bsh  * Driver for keyboard controller in SA-1111 companion chip.
     33       1.1      bsh  */
     34       1.1      bsh /*
     35       1.1      bsh  * Copyright (c) 1998
     36       1.1      bsh  *	Matthias Drochner.  All rights reserved.
     37       1.1      bsh  *
     38       1.1      bsh  * Redistribution and use in source and binary forms, with or without
     39       1.1      bsh  * modification, are permitted provided that the following conditions
     40       1.1      bsh  * are met:
     41       1.1      bsh  * 1. Redistributions of source code must retain the above copyright
     42       1.1      bsh  *    notice, this list of conditions and the following disclaimer.
     43       1.1      bsh  * 2. Redistributions in binary form must reproduce the above copyright
     44       1.1      bsh  *    notice, this list of conditions and the following disclaimer in the
     45       1.1      bsh  *    documentation and/or other materials provided with the distribution.
     46       1.1      bsh  *
     47       1.1      bsh  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     48       1.1      bsh  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     49       1.1      bsh  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     50       1.1      bsh  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     51       1.1      bsh  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     52       1.1      bsh  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     53       1.1      bsh  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     54       1.1      bsh  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     55       1.1      bsh  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     56       1.1      bsh  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     57       1.1      bsh  */
     58       1.2    lukem 
     59       1.2    lukem #include <sys/cdefs.h>
     60  1.9.42.1      mjf __KERNEL_RCSID(0, "$NetBSD: sa1111_kbc.c,v 1.9.42.1 2008/02/18 21:04:24 mjf Exp $");
     61       1.1      bsh 
     62       1.1      bsh #include <sys/param.h>
     63       1.1      bsh #include <sys/systm.h>
     64       1.1      bsh #include <sys/types.h>
     65       1.1      bsh #include <sys/callout.h>
     66       1.1      bsh #include <sys/kernel.h>
     67       1.1      bsh #include <sys/proc.h>
     68       1.1      bsh #include <sys/conf.h>
     69       1.1      bsh #include <sys/device.h>
     70       1.1      bsh #include <sys/malloc.h>
     71       1.1      bsh #include <sys/errno.h>
     72       1.1      bsh #include <sys/queue.h>
     73  1.9.42.1      mjf #include <sys/bus.h>
     74       1.1      bsh 
     75       1.1      bsh #include <arm/sa11x0/sa1111_reg.h>
     76       1.1      bsh #include <arm/sa11x0/sa1111_var.h>
     77       1.1      bsh 
     78       1.3    bjh21 #include <dev/pckbport/pckbportvar.h>		/* for prototypes */
     79       1.1      bsh 
     80       1.1      bsh #include "pckbd.h"
     81       1.1      bsh #include "rnd.h"
     82       1.1      bsh #include "locators.h"
     83       1.1      bsh 
     84       1.1      bsh struct sackbc_softc {
     85       1.1      bsh 	struct device dev;
     86       1.1      bsh 
     87       1.1      bsh 	bus_space_tag_t    iot;
     88       1.1      bsh 	bus_space_handle_t ioh;
     89       1.1      bsh 
     90       1.1      bsh 	void	*ih_rx;			/* receive interrupt */
     91       1.1      bsh 	int	intr;			/* interrupt number */
     92       1.6      bsh 	int	slot;		/* KBD_SLOT or AUX_SLOT */
     93       1.1      bsh 
     94       1.1      bsh 	int	polling;	/* don't process data in interrupt handler */
     95       1.1      bsh 	int	poll_stat;	/* data read from inr handler if polling */
     96       1.1      bsh 	int	poll_data;	/* status read from intr handler if polling */
     97       1.1      bsh 
     98       1.6      bsh #if NRND > 0
     99       1.6      bsh 	rndsource_element_t	rnd_source;
    100       1.6      bsh #endif
    101       1.3    bjh21 	pckbport_tag_t pt;
    102       1.1      bsh };
    103       1.1      bsh 
    104       1.9    peter static int	sackbc_match(struct device *, struct cfdata *, void *);
    105       1.9    peter static void	sackbc_attach(struct device *, struct device *, void *);
    106       1.3    bjh21 
    107       1.3    bjh21 static int	sackbc_xt_translation(void *, pckbport_slot_t, int);
    108       1.3    bjh21 #define sackbc_send_devcmd	sackbc_send_cmd
    109       1.3    bjh21 static int	sackbc_send_devcmd(void *, pckbport_slot_t, u_char);
    110       1.3    bjh21 static int	sackbc_poll_data1(void *, pckbport_slot_t);
    111       1.3    bjh21 static void	sackbc_slot_enable(void *, pckbport_slot_t, int);
    112       1.3    bjh21 static void	sackbc_intr_establish(void *, pckbport_slot_t);
    113       1.3    bjh21 static void	sackbc_set_poll(void *, pckbport_slot_t, int);
    114       1.1      bsh 
    115       1.1      bsh CFATTACH_DECL(sackbc, sizeof(struct sackbc_softc), sackbc_match,
    116       1.1      bsh     sackbc_attach, NULL, NULL);
    117       1.1      bsh 
    118       1.3    bjh21 static struct pckbport_accessops const sackbc_ops = {
    119       1.3    bjh21 	sackbc_xt_translation,
    120       1.3    bjh21 	sackbc_send_devcmd,
    121       1.3    bjh21 	sackbc_poll_data1,
    122       1.3    bjh21 	sackbc_slot_enable,
    123       1.3    bjh21 	sackbc_intr_establish,
    124       1.3    bjh21 	sackbc_set_poll
    125       1.3    bjh21 };
    126       1.1      bsh 
    127       1.1      bsh #define	KBD_DELAY	DELAY(8)
    128       1.1      bsh 
    129       1.1      bsh /*#define SACKBCDEBUG*/
    130       1.1      bsh 
    131       1.1      bsh #ifdef SACKBCDEBUG
    132       1.1      bsh #define DPRINTF(arg)  printf arg
    133       1.1      bsh #else
    134       1.1      bsh #define DPRINTF(arg)
    135       1.1      bsh #endif
    136       1.1      bsh 
    137       1.1      bsh 
    138       1.1      bsh static int
    139       1.1      bsh sackbc_match(struct device *parent, struct cfdata *cf, void *aux)
    140       1.1      bsh {
    141       1.1      bsh 	struct sa1111_attach_args *aa = (struct sa1111_attach_args *)aux;
    142       1.1      bsh 
    143       1.5      bsh 	switch (aa->sa_addr) {
    144       1.9    peter 	case SACC_KBD0:
    145       1.9    peter 	case SACC_KBD1:
    146       1.1      bsh 		return 1;
    147       1.1      bsh 	}
    148       1.1      bsh 	return 0;
    149       1.1      bsh }
    150       1.1      bsh 
    151       1.1      bsh #if 0
    152       1.1      bsh static int
    153       1.5      bsh sackbc_txint(void *cookie)
    154       1.1      bsh {
    155       1.1      bsh 	struct sackbc_softc *sc = cookie;
    156       1.1      bsh 
    157       1.5      bsh 	bus_space_read_4(sc->iot, sc->ioh, SACCKBD_STAT);
    158       1.1      bsh 
    159       1.1      bsh 	return 0;
    160       1.1      bsh }
    161       1.1      bsh #endif
    162       1.1      bsh 
    163       1.1      bsh static int
    164       1.5      bsh sackbc_rxint(void *cookie)
    165       1.1      bsh {
    166       1.1      bsh 	struct sackbc_softc *sc = cookie;
    167       1.9    peter 	int stat, code = -1;
    168       1.1      bsh 
    169       1.5      bsh 	stat = bus_space_read_4(sc->iot, sc->ioh, SACCKBD_STAT);
    170       1.5      bsh 	DPRINTF(("sackbc_rxint stat=%x\n", stat));
    171       1.5      bsh 	if (stat & KBDSTAT_RXF) {
    172       1.5      bsh 		code = bus_space_read_4(sc->iot, sc->ioh, SACCKBD_DATA);
    173       1.1      bsh 
    174       1.6      bsh #if NRND > 0
    175       1.6      bsh 		rnd_add_uint32(&sc->rnd_source, (stat<<8)|data);
    176       1.6      bsh #endif
    177       1.6      bsh 
    178       1.5      bsh 		if (sc->polling) {
    179       1.1      bsh 			sc->poll_data = code;
    180       1.1      bsh 			sc->poll_stat = stat;
    181       1.9    peter 		} else
    182       1.6      bsh 			pckbportintr(sc->pt, sc->slot, code);
    183       1.1      bsh 		return 1;
    184       1.1      bsh 	}
    185       1.1      bsh 
    186       1.1      bsh 	return 0;
    187       1.1      bsh }
    188       1.1      bsh 
    189       1.3    bjh21 static void
    190       1.3    bjh21 sackbc_intr_establish(void *cookie, pckbport_slot_t slot)
    191       1.1      bsh {
    192       1.3    bjh21 	struct sackbc_softc *sc = cookie;
    193       1.1      bsh 
    194       1.9    peter 	if (!(sc->polling) && sc->ih_rx == NULL) {
    195       1.5      bsh 		sc->ih_rx = sacc_intr_establish(
    196       1.8  thorpej 			(sacc_chipset_tag_t *) device_parent(&sc->dev),
    197       1.5      bsh 			sc->intr+1, IST_EDGE_RAISE, IPL_TTY, sackbc_rxint, sc);
    198       1.5      bsh 		if (sc->ih_rx == NULL) {
    199       1.5      bsh 			printf("%s: can't establish interrupt\n",
    200       1.5      bsh 			    sc->dev.dv_xname);
    201       1.1      bsh 		}
    202       1.1      bsh 	}
    203       1.1      bsh }
    204       1.1      bsh 
    205       1.1      bsh static void
    206       1.5      bsh sackbc_disable_intrhandler(struct sackbc_softc *sc)
    207       1.1      bsh {
    208       1.5      bsh 	if (sc->polling && sc->ih_rx) {
    209       1.5      bsh 		sacc_intr_disestablish(
    210       1.8  thorpej 			(sacc_chipset_tag_t *) device_parent(&sc->dev),
    211       1.5      bsh 			sc->ih_rx);
    212       1.1      bsh 		sc->ih_rx = NULL;
    213       1.1      bsh 	}
    214       1.1      bsh }
    215       1.1      bsh 
    216       1.1      bsh static	void
    217       1.1      bsh sackbc_attach(struct device *parent, struct device *self, void *aux)
    218       1.1      bsh {
    219       1.1      bsh 	struct sackbc_softc *sc = (struct sackbc_softc *)self;
    220       1.1      bsh 	struct sacc_softc *psc = (struct sacc_softc *)parent;
    221       1.1      bsh 	struct sa1111_attach_args *aa = (struct sa1111_attach_args *)aux;
    222       1.3    bjh21 	struct device *child;
    223       1.1      bsh 	uint32_t tmp, clock_bit;
    224       1.6      bsh 	int intr, slot;
    225       1.1      bsh 
    226       1.5      bsh 	switch (aa->sa_addr) {
    227       1.1      bsh 	case SACC_KBD0: clock_bit = (1<<6); intr = 21; break;
    228       1.1      bsh 	case SACC_KBD1: clock_bit = (1<<5); intr = 18; break;
    229       1.1      bsh 	default:
    230       1.1      bsh 		return;
    231       1.1      bsh 	}
    232       1.1      bsh 
    233       1.5      bsh 	if (aa->sa_size <= 0)
    234       1.1      bsh 		aa->sa_size = SACCKBD_SIZE;
    235       1.5      bsh 	if (aa->sa_intr == SACCCF_INTR_DEFAULT)
    236       1.1      bsh 		aa->sa_intr = intr;
    237       1.1      bsh 
    238       1.1      bsh 	sc->iot = psc->sc_iot;
    239       1.5      bsh 	if (bus_space_subregion(psc->sc_iot, psc->sc_ioh,
    240       1.5      bsh 	    aa->sa_addr, aa->sa_size, &sc->ioh)) {
    241       1.5      bsh 		printf(": can't map subregion\n");
    242       1.1      bsh 		return;
    243       1.1      bsh 	}
    244       1.1      bsh 
    245       1.1      bsh 	/* enable clock for PS/2 kbd or mouse */
    246       1.5      bsh 	tmp = bus_space_read_4(psc->sc_iot, psc->sc_ioh, SACCSC_SKPCR);
    247       1.5      bsh 	bus_space_write_4(psc->sc_iot, psc->sc_ioh, SACCSC_SKPCR,
    248       1.5      bsh 	    tmp | clock_bit);
    249       1.1      bsh 
    250       1.1      bsh 	sc->ih_rx = NULL;
    251       1.1      bsh 	sc->intr = aa->sa_intr;
    252       1.1      bsh 	sc->polling = 0;
    253       1.1      bsh 
    254       1.5      bsh 	tmp = bus_space_read_4(sc->iot, sc->ioh, SACCKBD_CR);
    255       1.5      bsh 	bus_space_write_4(sc->iot, sc->ioh, SACCKBD_CR, tmp | KBDCR_ENA);
    256       1.1      bsh 
    257       1.1      bsh 	/* XXX: this is necessary to get keyboard working. but I don't know why */
    258       1.5      bsh 	bus_space_write_4(sc->iot, sc->ioh, SACCKBD_CLKDIV, 2);
    259       1.1      bsh 
    260       1.5      bsh 	tmp = bus_space_read_4(sc->iot, sc->ioh, SACCKBD_STAT);
    261       1.5      bsh 	if ((tmp & KBDSTAT_ENA) == 0) {
    262       1.1      bsh 		printf("??? can't enable KBD controller\n");
    263       1.1      bsh 		return;
    264       1.1      bsh 	}
    265       1.1      bsh 
    266       1.1      bsh 	printf("\n");
    267       1.1      bsh 
    268       1.3    bjh21 	sc->pt = pckbport_attach(sc, &sackbc_ops);
    269       1.1      bsh 
    270       1.6      bsh 	/*
    271       1.9    peter 	 * Although there is no such thing as SLOT for SA-1111 kbd
    272       1.6      bsh 	 * controller, pckbd and pms drivers require it.
    273       1.6      bsh 	 */
    274       1.9    peter 	for (slot = PCKBPORT_KBD_SLOT; slot <= PCKBPORT_AUX_SLOT; ++slot) {
    275       1.6      bsh 		child = pckbport_attach_slot(self, sc->pt, slot);
    276       1.6      bsh 
    277       1.6      bsh 		if (child == NULL)
    278       1.6      bsh 			continue;
    279       1.6      bsh 		sc->slot = slot;
    280       1.6      bsh #if NRND > 0
    281       1.6      bsh 		rnd_attach_source(&sc->rnd_source, child->dv_xname,
    282       1.6      bsh 		    RND_TYPE_TTY, 0);
    283       1.1      bsh #endif
    284       1.6      bsh 		/* only one of KBD_SLOT or AUX_SLOT is used. */
    285       1.6      bsh 		break;
    286       1.6      bsh 	}
    287       1.1      bsh }
    288       1.1      bsh 
    289       1.1      bsh 
    290       1.1      bsh static inline int
    291       1.5      bsh sackbc_wait_output(struct sackbc_softc *sc)
    292       1.1      bsh {
    293       1.1      bsh 	u_int i, stat;
    294       1.1      bsh 
    295       1.1      bsh 	for (i = 100000; i; i--){
    296       1.1      bsh 		stat = bus_space_read_4(sc->iot, sc->ioh, SACCKBD_STAT);
    297       1.1      bsh 		delay(100);
    298       1.5      bsh 		if (stat & KBDSTAT_TXE)
    299       1.1      bsh 			return 1;
    300       1.1      bsh 	}
    301       1.1      bsh 	return 0;
    302       1.1      bsh }
    303       1.1      bsh 
    304       1.1      bsh static int
    305       1.5      bsh sackbc_poll_data1(void *cookie, pckbport_slot_t slot)
    306       1.1      bsh {
    307       1.3    bjh21 	struct sackbc_softc *sc = cookie;
    308       1.1      bsh 	int i, s, stat, c = -1;
    309       1.1      bsh 
    310       1.1      bsh 	s = spltty();
    311       1.1      bsh 
    312       1.1      bsh 	if (sc->polling){
    313       1.1      bsh 		stat	= sc->poll_stat;
    314       1.1      bsh 		c	= sc->poll_data;
    315       1.1      bsh 		sc->poll_data = -1;
    316       1.1      bsh 		sc->poll_stat = -1;
    317       1.5      bsh 		if (stat >= 0 &&
    318       1.5      bsh 		    (stat & (KBDSTAT_RXF|KBDSTAT_STP)) == KBDSTAT_RXF) {
    319       1.1      bsh 			splx(s);
    320       1.1      bsh 			return c;
    321       1.1      bsh 		}
    322       1.1      bsh 	}
    323       1.1      bsh 
    324       1.1      bsh 	/* if 1 port read takes 1us (?), this polls for 100ms */
    325       1.1      bsh 	for (i = 100000; i; i--) {
    326       1.1      bsh 		stat = bus_space_read_4(sc->iot, sc->ioh, SACCKBD_STAT);
    327       1.5      bsh 		if ((stat & (KBDSTAT_RXF|KBDSTAT_STP)) == KBDSTAT_RXF) {
    328       1.1      bsh 			KBD_DELAY;
    329       1.1      bsh 			c = bus_space_read_4(sc->iot, sc->ioh, SACCKBD_DATA);
    330       1.1      bsh 			break;
    331       1.1      bsh 		}
    332       1.1      bsh 	}
    333       1.1      bsh 
    334       1.1      bsh 	splx(s);
    335       1.9    peter 	return c;
    336       1.1      bsh }
    337       1.1      bsh 
    338       1.1      bsh static int
    339       1.5      bsh sackbc_send_cmd(void *cookie, pckbport_slot_t slot, u_char val)
    340       1.1      bsh {
    341       1.3    bjh21 	struct sackbc_softc *sc = cookie;
    342       1.3    bjh21 
    343       1.5      bsh 	if (!sackbc_wait_output(sc))
    344       1.9    peter 		return 0;
    345       1.5      bsh 	bus_space_write_1(sc->iot, sc->ioh, SACCKBD_DATA, val);
    346       1.9    peter 	return 1;
    347       1.1      bsh }
    348       1.1      bsh 
    349       1.1      bsh 
    350       1.1      bsh /*
    351       1.1      bsh  * Glue functions for pckbd on sackbc.
    352       1.1      bsh  * These functions emulate those in dev/ic/pckbc.c.
    353       1.1      bsh  *
    354       1.1      bsh  */
    355       1.1      bsh 
    356       1.1      bsh /*
    357       1.1      bsh  * switch scancode translation on / off
    358       1.1      bsh  * return nonzero on success
    359       1.1      bsh  */
    360       1.3    bjh21 static int
    361       1.3    bjh21 sackbc_xt_translation(void *self, pckbport_slot_t slot, int on)
    362       1.1      bsh {
    363       1.1      bsh 	/* KBD/Mouse controller doesn't have scancode translation */
    364       1.1      bsh 	return !on;
    365       1.1      bsh }
    366       1.1      bsh 
    367       1.3    bjh21 static void
    368       1.3    bjh21 sackbc_slot_enable(void *self, pckbport_slot_t slot, int on)
    369       1.1      bsh {
    370       1.1      bsh #if 0
    371       1.1      bsh 	struct sackbc_softc *sc = (struct sackbc_softc *) self;
    372       1.1      bsh 	int cmd;
    373       1.1      bsh 
    374       1.1      bsh 	cmd = on ? KBC_KBDENABLE : KBC_KBDDISABLE;
    375       1.5      bsh 	if (!sackbc_send_cmd(sc, cmd))
    376       1.1      bsh 		printf("sackbc_slot_enable(%d) failed\n", on);
    377       1.1      bsh #endif
    378       1.1      bsh }
    379       1.1      bsh 
    380       1.1      bsh 
    381       1.3    bjh21 static void
    382       1.3    bjh21 sackbc_set_poll(void *self, pckbport_slot_t slot, int on)
    383       1.1      bsh {
    384       1.1      bsh 	struct sackbc_softc *sc = (struct sackbc_softc *)self;
    385       1.1      bsh 	int s;
    386       1.1      bsh 
    387       1.1      bsh 	s = spltty();
    388       1.1      bsh 
    389       1.5      bsh 	if (sc->polling != on) {
    390       1.1      bsh 
    391       1.1      bsh 		sc->polling = on;
    392       1.1      bsh 
    393       1.5      bsh 		if (on) {
    394       1.1      bsh 			sc->poll_data = sc->poll_stat = -1;
    395       1.1      bsh 			sackbc_disable_intrhandler(sc);
    396       1.9    peter 		} else {
    397       1.1      bsh 			/*
    398       1.1      bsh 			 * If disabling polling on a device that's
    399       1.1      bsh 			 * been configured, make sure there are no
    400       1.1      bsh 			 * bytes left in the FIFO, holding up the
    401       1.1      bsh 			 * interrupt line.  Otherwise we won't get any
    402       1.1      bsh 			 * further interrupts.
    403       1.1      bsh 			 */
    404       1.1      bsh 			sackbc_rxint(sc);
    405       1.6      bsh 			sackbc_intr_establish(sc, sc->slot);
    406       1.1      bsh 		}
    407       1.1      bsh 	}
    408       1.1      bsh 	splx(s);
    409       1.1      bsh }
    410