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cardslot.c revision 1.4
      1  1.4  haya /*	$NetBSD: cardslot.c,v 1.4 1999/10/29 07:27:43 haya Exp $	*/
      2  1.1  haya /*
      3  1.1  haya  * Copyright (c) 1999
      4  1.1  haya  *       HAYAKAWA Koichi.  All rights reserved.
      5  1.1  haya  *
      6  1.1  haya  * Redistribution and use in source and binary forms, with or without
      7  1.1  haya  * modification, are permitted provided that the following conditions
      8  1.1  haya  * are met:
      9  1.1  haya  * 1. Redistributions of source code must retain the above copyright
     10  1.1  haya  *    notice, this list of conditions and the following disclaimer.
     11  1.1  haya  * 2. Redistributions in binary form must reproduce the above copyright
     12  1.1  haya  *    notice, this list of conditions and the following disclaimer in the
     13  1.1  haya  *    documentation and/or other materials provided with the distribution.
     14  1.1  haya  * 3. All advertising materials mentioning features or use of this software
     15  1.1  haya  *    must display the following acknowledgement:
     16  1.1  haya  *	This product includes software developed by HAYAKAWA Koichi.
     17  1.1  haya  * 4. The name of the author may not be used to endorse or promote products
     18  1.1  haya  *    derived from this software without specific prior written permission.
     19  1.1  haya  *
     20  1.1  haya  *
     21  1.1  haya  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     22  1.1  haya  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     23  1.1  haya  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     24  1.1  haya  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
     25  1.1  haya  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     26  1.1  haya  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
     27  1.1  haya  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     28  1.1  haya  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     29  1.1  haya  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
     30  1.1  haya  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     31  1.1  haya  * POSSIBILITY OF SUCH DAMAGE.
     32  1.1  haya  */
     33  1.1  haya 
     34  1.3  haya #include "opt_cardslot.h"
     35  1.1  haya 
     36  1.1  haya #include <sys/types.h>
     37  1.1  haya #include <sys/param.h>
     38  1.1  haya #include <sys/systm.h>
     39  1.1  haya #include <sys/device.h>
     40  1.1  haya #include <sys/malloc.h>
     41  1.1  haya #include <sys/kernel.h>
     42  1.1  haya #include <sys/syslog.h>
     43  1.1  haya #include <sys/kthread.h>
     44  1.1  haya 
     45  1.1  haya #include <machine/bus.h>
     46  1.1  haya 
     47  1.1  haya #include <dev/cardbus/cardslotvar.h>
     48  1.1  haya #include <dev/cardbus/cardbusvar.h>
     49  1.1  haya #include <dev/pcmcia/pcmciavar.h>
     50  1.1  haya #include <dev/pcmcia/pcmciachip.h>
     51  1.1  haya #include <dev/ic/i82365var.h>
     52  1.1  haya 
     53  1.1  haya 
     54  1.1  haya #if defined CARDSLOT_DEBUG
     55  1.1  haya #define STATIC
     56  1.1  haya #define DPRINTF(a) printf a
     57  1.1  haya #define DDELAY(x) delay((x)*1000*1000)
     58  1.1  haya #else
     59  1.1  haya #define STATIC static
     60  1.1  haya #define DPRINTF(a)
     61  1.1  haya #endif
     62  1.1  haya 
     63  1.1  haya 
     64  1.1  haya 
     65  1.1  haya STATIC void cardslotattach __P((struct device *, struct device *, void *));
     66  1.1  haya 
     67  1.1  haya #if !defined __BROKEN_INDIRECT_CONFIG
     68  1.1  haya STATIC int cardslotmatch __P((struct device *, struct cfdata *, void *));
     69  1.1  haya #else
     70  1.1  haya STATIC int cardslotmatch __P((struct device *, void *, void *));
     71  1.1  haya #endif
     72  1.1  haya static void create_slot_manager __P((void *));
     73  1.1  haya static void cardslot_event_thread __P((void *arg));
     74  1.1  haya 
     75  1.1  haya STATIC int cardslot_cb_print __P((void *aux, const char *pcic));
     76  1.1  haya static int cardslot_16_print __P((void *, const char *));
     77  1.1  haya static int cardslot_16_submatch __P((struct device *, struct cfdata *,void *));
     78  1.1  haya 
     79  1.1  haya struct cfattach cardslot_ca = {
     80  1.1  haya 	sizeof(struct cardslot_softc), cardslotmatch, cardslotattach
     81  1.1  haya };
     82  1.1  haya 
     83  1.1  haya #ifndef __NetBSD_Version__
     84  1.1  haya struct cfdriver cardslot_cd = {
     85  1.1  haya 	NULL, "cardslot", DV_DULL
     86  1.1  haya };
     87  1.1  haya #endif
     88  1.1  haya 
     89  1.1  haya 
     90  1.1  haya STATIC int
     91  1.1  haya #if defined __BROKEN_INDIRECT_CONFIG
     92  1.1  haya cardslotmatch(parent, match, aux)
     93  1.1  haya      struct device *parent;
     94  1.1  haya      void *match;
     95  1.1  haya      void *aux;
     96  1.1  haya #else
     97  1.1  haya cardslotmatch(parent, cf, aux)
     98  1.1  haya      struct device *parent;
     99  1.1  haya      struct cfdata *cf;
    100  1.1  haya      void *aux;
    101  1.1  haya #endif
    102  1.1  haya {
    103  1.1  haya #if defined __BROKEN_INDIRECT_CONFIG
    104  1.1  haya   struct cfdata *cf = match;
    105  1.1  haya #endif
    106  1.1  haya   struct cardslot_attach_args *caa = aux;
    107  1.1  haya 
    108  1.1  haya   if (caa->caa_cb_attach == NULL && caa->caa_16_attach == NULL) {
    109  1.1  haya     /* Neither CardBus nor 16-bit PCMCIA are defined. */
    110  1.1  haya     return 0;
    111  1.1  haya   }
    112  1.1  haya 
    113  1.1  haya   return 1;
    114  1.1  haya }
    115  1.1  haya 
    116  1.1  haya 
    117  1.1  haya 
    118  1.1  haya STATIC void
    119  1.1  haya cardslotattach(parent, self, aux)
    120  1.1  haya      struct device *parent;
    121  1.1  haya      struct device *self;
    122  1.1  haya      void *aux;
    123  1.1  haya {
    124  1.1  haya   struct cardslot_softc *sc = (struct cardslot_softc *)self;
    125  1.1  haya   struct cardslot_attach_args *caa = aux;
    126  1.1  haya 
    127  1.1  haya   struct cbslot_attach_args *cba = caa->caa_cb_attach;
    128  1.1  haya   struct pcmciabus_attach_args *pa = caa->caa_16_attach;
    129  1.1  haya 
    130  1.1  haya   struct cardbus_softc *csc;
    131  1.1  haya   struct pcmcia_softc *psc;
    132  1.1  haya 
    133  1.1  haya   int card_attach_now;
    134  1.1  haya 
    135  1.1  haya   sc->sc_slot = sc->sc_dev.dv_unit;
    136  1.1  haya   sc->sc_cb_softc = NULL;
    137  1.1  haya   sc->sc_16_softc = NULL;
    138  1.1  haya   SIMPLEQ_INIT(&sc->sc_events);
    139  1.1  haya   sc->sc_th_enable = 0;
    140  1.1  haya 
    141  1.1  haya   printf(" slot %d flags %x\n", sc->sc_slot, sc->sc_dev.dv_cfdata->cf_flags);
    142  1.1  haya 
    143  1.1  haya   DPRINTF(("%s attaching CardBus bus...\n", sc->sc_dev.dv_xname));
    144  1.1  haya   if (cba != NULL) {
    145  1.1  haya     if (NULL != (csc = (void *)config_found(self, cba, cardslot_cb_print))) {
    146  1.1  haya       /* cardbus found */
    147  1.1  haya       DPRINTF(("cardslotattach: found cardbus on %s\n", sc->sc_dev.dv_xname));
    148  1.1  haya       sc->sc_cb_softc = csc;
    149  1.1  haya     }
    150  1.1  haya   }
    151  1.1  haya 
    152  1.1  haya   if (pa != NULL) {
    153  1.1  haya     if (NULL != (psc = (void *)config_found_sm(self, pa, cardslot_16_print,
    154  1.1  haya 				       cardslot_16_submatch))) {
    155  1.1  haya       /* pcmcia 16-bit bus found */
    156  1.1  haya       DPRINTF(("cardslotattach: found 16-bit pcmcia bus\n"));
    157  1.1  haya       sc->sc_16_softc = psc;
    158  1.1  haya       /* XXX: dirty.  This code should be removed to achieve MI */
    159  1.1  haya       caa->caa_ph->pcmcia = (struct device *)psc;
    160  1.1  haya     }
    161  1.1  haya   }
    162  1.1  haya 
    163  1.1  haya   if (csc != NULL || psc != NULL) {
    164  1.1  haya #if __NetBSD_Version__ > 104060000
    165  1.1  haya     kthread_create(create_slot_manager, (void *)sc);
    166  1.1  haya #else
    167  1.1  haya     kthread_create_deferred(create_slot_manager, (void *)sc);
    168  1.1  haya #endif
    169  1.1  haya   }
    170  1.1  haya 
    171  1.1  haya   card_attach_now = sc->sc_dev.dv_cfdata->cf_flags & 0x01;
    172  1.1  haya 
    173  1.1  haya   if (csc && (csc->sc_cf->cardbus_ctrl)(csc->sc_cc, CARDBUS_CD)) {
    174  1.1  haya     DPRINTF(("cardslotattach: CardBus card found\n"));
    175  1.1  haya     if (card_attach_now) {
    176  1.1  haya       /* attach now */
    177  1.1  haya       cardbus_attach_card(sc->sc_cb_softc);
    178  1.1  haya       CARDSLOT_SET_CARDTYPE(sc->sc_status, CARDSLOT_STATUS_CARD_CB);
    179  1.1  haya     } else {
    180  1.1  haya       /* attach deffered */
    181  1.1  haya       cardslot_event_throw(sc, CARDSLOT_EVENT_INSERTION_CB);
    182  1.1  haya     }
    183  1.1  haya   }
    184  1.1  haya 
    185  1.1  haya   if (psc && (psc->pct->card_detect)(psc->pch)) {
    186  1.1  haya     DPRINTF(("cardbusattach: 16-bit card found\n"));
    187  1.1  haya     if (card_attach_now) {
    188  1.1  haya       /* attach now */
    189  1.1  haya       pcmcia_card_attach((struct device *)sc->sc_16_softc);
    190  1.1  haya       CARDSLOT_SET_CARDTYPE(sc->sc_status, CARDSLOT_STATUS_CARD_16);
    191  1.1  haya     } else {
    192  1.1  haya       /* attach deffered */
    193  1.1  haya       cardslot_event_throw(sc, CARDSLOT_EVENT_INSERTION_16);
    194  1.1  haya     }
    195  1.1  haya   }
    196  1.1  haya }
    197  1.1  haya 
    198  1.1  haya 
    199  1.1  haya 
    200  1.1  haya STATIC int
    201  1.4  haya cardslot_cb_print(aux, pnp)
    202  1.1  haya      void *aux;
    203  1.4  haya      const char *pnp;
    204  1.1  haya {
    205  1.4  haya   struct cbslot_attach_args *cba = aux;
    206  1.4  haya 
    207  1.4  haya   if (pnp) {
    208  1.4  haya     printf("cardbus at %s", pnp);
    209  1.4  haya     printf(" function %d subordinate bus %d", cba->cba_function, cba->cba_bus);
    210  1.4  haya   }
    211  1.4  haya 
    212  1.1  haya   return UNCONF;
    213  1.1  haya }
    214  1.1  haya 
    215  1.1  haya 
    216  1.1  haya static int
    217  1.1  haya cardslot_16_submatch(parent, cf, aux)
    218  1.1  haya      struct device *parent;
    219  1.1  haya      struct cfdata *cf;
    220  1.1  haya      void *aux;
    221  1.1  haya {
    222  1.1  haya   if (cf->cf_loc[PCMCIABUSCF_CONTROLLER] != PCMCIABUSCF_CONTROLLER_DEFAULT
    223  1.1  haya       && cf->cf_loc[PCMCIABUSCF_CONTROLLER] != 0) {
    224  1.1  haya     return 0;
    225  1.1  haya   }
    226  1.1  haya 
    227  1.1  haya   if ((cf->cf_loc[PCMCIABUSCF_CONTROLLER] == PCMCIABUSCF_CONTROLLER_DEFAULT)) {
    228  1.1  haya     return ((*cf->cf_attach->ca_match)(parent, cf, aux));
    229  1.1  haya   }
    230  1.1  haya 
    231  1.1  haya   return 0;
    232  1.1  haya }
    233  1.1  haya 
    234  1.1  haya 
    235  1.1  haya 
    236  1.1  haya static int
    237  1.1  haya cardslot_16_print(arg, pnp)
    238  1.1  haya      void *arg;
    239  1.1  haya      const char *pnp;
    240  1.1  haya {
    241  1.4  haya 
    242  1.1  haya   if (pnp) {
    243  1.4  haya     printf("pcmciabus at %s", pnp);
    244  1.1  haya   }
    245  1.1  haya 
    246  1.1  haya   return UNCONF;
    247  1.1  haya }
    248  1.1  haya 
    249  1.1  haya 
    250  1.1  haya 
    251  1.1  haya 
    252  1.1  haya static void
    253  1.1  haya create_slot_manager(arg)
    254  1.1  haya      void *arg;
    255  1.1  haya {
    256  1.1  haya   struct cardslot_softc *sc = (struct cardslot_softc *)arg;
    257  1.1  haya 
    258  1.1  haya   sc->sc_th_enable = 1;
    259  1.1  haya 
    260  1.1  haya #if __NetBSD_Version__ > 104060000
    261  1.1  haya  if (kthread_create1(cardslot_event_thread, sc, &sc->sc_event_thread, "%s",
    262  1.1  haya 		     sc->sc_dev.dv_xname)) {
    263  1.1  haya #else
    264  1.1  haya  if (kthread_create(cardslot_event_thread, sc, &sc->sc_event_thread, "%s",
    265  1.1  haya 		     sc->sc_dev.dv_xname)) {
    266  1.1  haya #endif
    267  1.1  haya     printf("%s: unable to create event thread for slot %d\n",
    268  1.1  haya 	   sc->sc_dev.dv_xname, sc->sc_slot);
    269  1.1  haya     panic("create_slot_manager");
    270  1.1  haya   }
    271  1.1  haya }
    272  1.1  haya 
    273  1.1  haya 
    274  1.1  haya 
    275  1.1  haya 
    276  1.1  haya /*
    277  1.1  haya  * void cardslot_event_throw(struct cardslot_softc *sc, int ev)
    278  1.1  haya  *
    279  1.1  haya  *   This function throws an event to the event handler.  If the state
    280  1.1  haya  *   of a slot is changed, it should be noticed using this function.
    281  1.1  haya  */
    282  1.1  haya void
    283  1.1  haya cardslot_event_throw(sc, ev)
    284  1.1  haya      struct cardslot_softc *sc;
    285  1.1  haya      int ev;
    286  1.1  haya {
    287  1.1  haya   struct cardslot_event *ce;
    288  1.1  haya 
    289  1.1  haya   DPRINTF(("cardslot_event_throw: an event %s comes\n",
    290  1.1  haya 	   ev == CARDSLOT_EVENT_INSERTION_CB ? "CardBus Card inserted" :
    291  1.1  haya 	   ev == CARDSLOT_EVENT_INSERTION_16 ? "16-bit Card inserted" :
    292  1.1  haya 	   ev == CARDSLOT_EVENT_REMOVAL_CB ? "CardBus Card removed" :
    293  1.1  haya 	   ev == CARDSLOT_EVENT_REMOVAL_16 ? "16-bit Card removed" : "???"));
    294  1.1  haya 
    295  1.1  haya   if (NULL == (ce = (struct cardslot_event *)malloc(sizeof (struct cardslot_event), M_TEMP, M_NOWAIT))) {
    296  1.1  haya     panic("cardslot_enevt");
    297  1.1  haya   }
    298  1.1  haya 
    299  1.1  haya   ce->ce_type = ev;
    300  1.1  haya 
    301  1.1  haya   {
    302  1.1  haya     int s = spltty();
    303  1.1  haya     SIMPLEQ_INSERT_TAIL(&sc->sc_events, ce, ce_q);
    304  1.1  haya     splx(s);
    305  1.1  haya   }
    306  1.1  haya 
    307  1.1  haya   wakeup(&sc->sc_events);
    308  1.1  haya 
    309  1.1  haya   return;
    310  1.1  haya }
    311  1.1  haya 
    312  1.1  haya 
    313  1.1  haya /*
    314  1.1  haya  * static void cardslot_event_thread(void *arg)
    315  1.1  haya  *
    316  1.1  haya  *   This function is the main routine handing cardslot events such as
    317  1.1  haya  *   insertions and removals.
    318  1.1  haya  *
    319  1.1  haya  */
    320  1.1  haya static void
    321  1.1  haya cardslot_event_thread(arg)
    322  1.1  haya      void *arg;
    323  1.1  haya {
    324  1.1  haya   struct cardslot_softc *sc = arg;
    325  1.1  haya   struct cardslot_event *ce;
    326  1.1  haya   int s;
    327  1.1  haya   static int antonym_ev[4] = {
    328  1.1  haya     CARDSLOT_EVENT_REMOVAL_16, CARDSLOT_EVENT_INSERTION_16,
    329  1.1  haya     CARDSLOT_EVENT_REMOVAL_CB, CARDSLOT_EVENT_INSERTION_CB
    330  1.1  haya   };
    331  1.1  haya 
    332  1.1  haya   while (sc->sc_th_enable) {
    333  1.1  haya     s = spltty();
    334  1.1  haya     if ((ce = SIMPLEQ_FIRST(&sc->sc_events)) == NULL) {
    335  1.1  haya       splx(s);
    336  1.1  haya       (void) tsleep(&sc->sc_events, PWAIT, "cardslotev", 0);
    337  1.1  haya       continue;
    338  1.1  haya     }
    339  1.1  haya     SIMPLEQ_REMOVE_HEAD(&sc->sc_events, ce, ce_q);
    340  1.1  haya     splx(s);
    341  1.1  haya 
    342  1.1  haya     if (IS_CARDSLOT_INSERT_REMOVE_EV(ce->ce_type)) {
    343  1.1  haya       /* Chattering supression */
    344  1.1  haya       s = spltty();
    345  1.1  haya       while (1) {
    346  1.1  haya 	struct cardslot_event *ce1, *ce2;
    347  1.1  haya 
    348  1.1  haya 	if ((ce1 = SIMPLEQ_FIRST(&sc->sc_events)) == NULL) {
    349  1.1  haya 	  break;
    350  1.1  haya 	}
    351  1.1  haya 	if (ce1->ce_type != antonym_ev[ce->ce_type]) {
    352  1.1  haya 	  break;
    353  1.1  haya 	}
    354  1.1  haya 	if ((ce2 = SIMPLEQ_NEXT(ce1, ce_q)) == NULL) {
    355  1.1  haya 	  break;
    356  1.1  haya 	}
    357  1.1  haya 	if (ce2->ce_type == ce->ce_type) {
    358  1.1  haya 	  SIMPLEQ_REMOVE_HEAD(&sc->sc_events, ce1, ce_q);
    359  1.1  haya 	  free(ce1, M_TEMP);
    360  1.1  haya 	  SIMPLEQ_REMOVE_HEAD(&sc->sc_events, ce2, ce_q);
    361  1.1  haya 	  free(ce2, M_TEMP);
    362  1.1  haya 	}
    363  1.1  haya       }
    364  1.1  haya       splx(s);
    365  1.1  haya     }
    366  1.1  haya 
    367  1.1  haya     switch (ce->ce_type) {
    368  1.1  haya     case CARDSLOT_EVENT_INSERTION_CB:
    369  1.1  haya       if (CARDSLOT_CARDTYPE(sc->sc_status) != CARDSLOT_STATUS_CARD_NONE) {
    370  1.1  haya 	/* A card has already been inserted. */
    371  1.1  haya 	break;
    372  1.1  haya       }
    373  1.1  haya       if (sc->sc_cb_softc) {
    374  1.1  haya 	cardbus_attach_card(sc->sc_cb_softc);
    375  1.1  haya 	CARDSLOT_SET_CARDTYPE(sc->sc_status, CARDSLOT_STATUS_CARD_CB);
    376  1.1  haya       } else {
    377  1.1  haya 	panic("no cardbus on %s", sc->sc_dev.dv_xname);
    378  1.1  haya       }
    379  1.1  haya 
    380  1.1  haya       break;
    381  1.1  haya 
    382  1.1  haya     case CARDSLOT_EVENT_INSERTION_16:
    383  1.1  haya       if (CARDSLOT_CARDTYPE(sc->sc_status) != CARDSLOT_STATUS_CARD_NONE) {
    384  1.1  haya 	/* A card has already been inserted. */
    385  1.1  haya 	break;
    386  1.1  haya       }
    387  1.1  haya       if (sc->sc_16_softc) {
    388  1.1  haya 	pcmcia_card_attach((struct device *)sc->sc_16_softc);
    389  1.1  haya 	CARDSLOT_SET_CARDTYPE(sc->sc_status, CARDSLOT_STATUS_CARD_16);
    390  1.1  haya       } else {
    391  1.1  haya 	panic("no 16-bit pcmcia on %s", sc->sc_dev.dv_xname);
    392  1.1  haya       }
    393  1.1  haya 
    394  1.1  haya       break;
    395  1.1  haya 
    396  1.1  haya     case CARDSLOT_EVENT_REMOVAL_CB:
    397  1.1  haya       if (CARDSLOT_CARDTYPE(sc->sc_status) != CARDSLOT_STATUS_CARD_CB) {
    398  1.1  haya 	/* CardBus card has not been inserted. */
    399  1.1  haya 	break;
    400  1.1  haya       }
    401  1.1  haya 				/* not yet */
    402  1.1  haya       CARDSLOT_SET_CARDTYPE(sc->sc_status, CARDSLOT_STATUS_CARD_NONE);
    403  1.1  haya       break;
    404  1.1  haya 
    405  1.1  haya     case CARDSLOT_EVENT_REMOVAL_16:
    406  1.1  haya       DPRINTF(("%s: removal event\n", sc->sc_dev.dv_xname));
    407  1.1  haya       if (CARDSLOT_CARDTYPE(sc->sc_status) != CARDSLOT_STATUS_CARD_16) {
    408  1.1  haya 	/* 16-bit card has not been inserted. */
    409  1.1  haya 	break;
    410  1.1  haya       }
    411  1.1  haya       if (sc->sc_16_softc) {
    412  1.1  haya 	struct pcmcia_softc *psc = sc->sc_16_softc;
    413  1.1  haya 
    414  1.1  haya 	pcmcia_card_deactivate((struct device *)psc);
    415  1.1  haya 	pcmcia_chip_socket_disable(psc->pct, psc->pch);
    416  1.1  haya 	pcmcia_card_detach((struct device *)psc, DETACH_FORCE);
    417  1.1  haya 	CARDSLOT_SET_CARDTYPE(sc->sc_status, CARDSLOT_STATUS_CARD_NONE);
    418  1.1  haya       }
    419  1.1  haya       break;
    420  1.1  haya 
    421  1.1  haya     default:
    422  1.1  haya       panic("cardslot_event_thread: unknown event %d", ce->ce_type);
    423  1.1  haya     }
    424  1.1  haya     free(ce, M_TEMP);
    425  1.1  haya   }
    426  1.1  haya 
    427  1.1  haya   sc->sc_event_thread = NULL;
    428  1.1  haya 
    429  1.1  haya   /* In case parent is waiting for us to exit. */
    430  1.1  haya   wakeup(sc);
    431  1.1  haya 
    432  1.1  haya   kthread_exit(0);
    433  1.1  haya }
    434