sys/dev/ppbus/pps.c

   1 /*
   2  * ----------------------------------------------------------------------------
   3  * "THE BEER-WARE LICENSE" (Revision 42):
   4  * <phk@FreeBSD.org> wrote this file.  As long as you retain this notice you
   5  * can do whatever you want with this stuff. If we meet some day, and you think
   6  * this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
   7  * ----------------------------------------------------------------------------
   8  *
   9  * $Id: pps.c,v 1.19 1999/05/31 11:25:00 phk Exp $
  10  *
  11  * This driver implements a draft-mogul-pps-api-02.txt PPS source.
  12  *
  13  * The input pin is pin#10
  14  * The echo output pin is pin#14
  15  *
  16  */
  17
  18 #include <sys/param.h>
  19 #include <sys/kernel.h>
  20 #include <sys/systm.h>
  21 #include <sys/conf.h>
  22 #include <sys/timepps.h>
  23 #include <sys/malloc.h>
  24
  25 #include <dev/ppbus/ppbconf.h>
  26 #include "pps.h"
  27
  28 #define PPS_NAME        "pps"           /* our official name */
  29
  30 struct pps_data {
  31         int     pps_open;
  32         struct  ppb_device pps_dev;
  33         struct  pps_state pps;
  34 };
  35
  36 static int npps;
  37
  38 /*
  39  * Make ourselves visible as a ppbus driver
  40  */
  41
  42 static struct ppb_device        *ppsprobe(struct ppb_data *ppb);
  43 static int                      ppsattach(struct ppb_device *dev);
  44 static void                     ppsintr(struct ppb_device *ppd);
  45
  46 static struct ppb_driver ppsdriver = {
  47     ppsprobe, ppsattach, PPS_NAME
  48 };
  49
  50 DATA_SET(ppbdriver_set, ppsdriver);
  51
  52 static  d_open_t        ppsopen;
  53 static  d_close_t       ppsclose;
  54 static  d_ioctl_t       ppsioctl;
  55
  56 #define CDEV_MAJOR 89
  57 static struct cdevsw pps_cdevsw = {
  58         /* open */      ppsopen,
  59         /* close */     ppsclose,
  60         /* read */      noread,
  61         /* write */     nowrite,
  62         /* ioctl */     ppsioctl,
  63         /* stop */      nostop,
  64         /* reset */     noreset,
  65         /* devtotty */  nodevtotty,
  66         /* poll */      nopoll,
  67         /* mmap */      nommap,
  68         /* strategy */  nostrategy,
  69         /* name */      PPS_NAME,
  70         /* parms */     noparms,
  71         /* maj */       CDEV_MAJOR,
  72         /* dump */      nodump,
  73         /* psize */     nopsize,
  74         /* flags */     0,
  75         /* maxio */     0,
  76         /* bmaj */      -1
  77 };
  78
  79
  80 static struct ppb_device *
  81 ppsprobe(struct ppb_data *ppb)
  82 {
  83         struct pps_data *sc;
  84         static int once;
  85         dev_t dev;
  86
  87         if (!once++)
  88                 cdevsw_add(&pps_cdevsw);
  89
  90         sc = (struct pps_data *) malloc(sizeof(struct pps_data),
  91                                                         M_TEMP, M_NOWAIT);
  92         if (!sc) {
  93                 printf(PPS_NAME ": cannot malloc!\n");
  94                 return (0);
  95         }
  96         bzero(sc, sizeof(struct pps_data));
  97
  98         dev = make_dev(&pps_cdevsw, npps,
  99             UID_ROOT, GID_WHEEL, 0644, PPS_NAME "%d", npps);
 100
 101         dev->si_drv1 = sc;
 102
 103         sc->pps_dev.id_unit = npps++;
 104         sc->pps_dev.ppb = ppb;
 105         sc->pps_dev.name = ppsdriver.name;
 106         sc->pps_dev.bintr = ppsintr;
 107         sc->pps_dev.drv1 = sc;
 108
 109         sc->pps.ppscap = PPS_CAPTUREASSERT | PPS_ECHOASSERT;
 110         pps_init(&sc->pps);
 111         return (&sc->pps_dev);
 112 }
 113
 114 static int
 115 ppsattach(struct ppb_device *dev)
 116 {
 117
 118         /*
 119          * Report ourselves
 120          */
 121         printf(PPS_NAME "%d: <Pulse per second Timing Interface> on ppbus %d\n",
 122                dev->id_unit, dev->ppb->ppb_link->adapter_unit);
 123
 124         return (1);
 125 }
 126
 127 static  int
 128 ppsopen(dev_t dev, int flags, int fmt, struct proc *p)
 129 {
 130         struct pps_data *sc;
 131         u_int unit = minor(dev);
 132
 133         if ((unit >= npps))
 134                 return (ENXIO);
 135
 136         sc = dev->si_drv1;
 137
 138         if (!sc->pps_open) {
 139                 if (ppb_request_bus(&sc->pps_dev, PPB_WAIT|PPB_INTR))
 140                         return (EINTR);
 141
 142                 ppb_wctr(&sc->pps_dev, 0);
 143                 ppb_wctr(&sc->pps_dev, IRQENABLE);
 144                 sc->pps_open = 1;
 145         }
 146
 147         return(0);
 148 }
 149
 150 static  int
 151 ppsclose(dev_t dev, int flags, int fmt, struct proc *p)
 152 {
 153         struct pps_data *sc = dev->si_drv1;
 154
 155         sc->pps.ppsparam.mode = 0;      /* PHK ??? */
 156
 157         ppb_wdtr(&sc->pps_dev, 0);
 158         ppb_wctr(&sc->pps_dev, 0);
 159
 160         ppb_release_bus(&sc->pps_dev);
 161         sc->pps_open = 0;
 162         return(0);
 163 }
 164
 165 static void
 166 ppsintr(struct ppb_device *ppd)
 167 {
 168         struct pps_data *sc = ppd->drv1;
 169         struct timecounter *tc;
 170         unsigned count;
 171
 172         tc = timecounter;
 173         count = timecounter->tc_get_timecount(tc);
 174         if (!(ppb_rstr(&sc->pps_dev) & nACK))
 175                 return;
 176         if (sc->pps.ppsparam.mode & PPS_ECHOASSERT)
 177                 ppb_wctr(&sc->pps_dev, IRQENABLE | AUTOFEED);
 178         pps_event(&sc->pps, tc, count, PPS_CAPTUREASSERT);
 179         if (sc->pps.ppsparam.mode & PPS_ECHOASSERT)
 180                 ppb_wctr(&sc->pps_dev, IRQENABLE);
 181 }
 182
 183 static int
 184 ppsioctl(dev_t dev, u_long cmd, caddr_t data, int flags, struct proc *p)
 185 {
 186         struct pps_data *sc = dev->si_drv1;
 187
 188         return (pps_ioctl(cmd, data, &sc->pps));
 189 }
 190