ecbb00a262
FreeBSD/alpha. The most significant item is to change the command argument to ioctl functions from int to u_long. This change brings us inline with various other BSD versions. Driver writers may like to use (__FreeBSD_version == 300003) to detect this change. The prototype FreeBSD/alpha machdep will follow in a couple of days time.
664 lines
21 KiB
C
664 lines
21 KiB
C
/*
|
|
* Copyright (c) 1998 Scottibox
|
|
* All rights reserved.
|
|
*
|
|
*
|
|
* 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
|
|
* in this position and unchanged.
|
|
* 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. The name of the author may not be used to endorse or promote products
|
|
* derived from this software without specific prior written permission
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
|
|
*
|
|
* Industrial Computer Source model AIO8-P
|
|
* 8 channel, moderate speed analog to digital converter board with
|
|
* 128 channel MUX capability via daisy chained AT-16P units
|
|
* alog.c, character device driver, last revised January 6 1998
|
|
* See http://www.scottibox.com
|
|
* http://www.indcompsrc.com/products/data/html/aio8g-p.html
|
|
* http://www.indcompsrc.com/products/data/html/at16-p.html
|
|
*
|
|
* Written by: Jamil J. Weatherbee <jamil@scottibox.com>
|
|
*
|
|
*/
|
|
|
|
|
|
/* Include Files */
|
|
|
|
#include "alog.h"
|
|
#if NALOG > 0
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/fcntl.h>
|
|
#include <sys/malloc.h>
|
|
#include <sys/poll.h>
|
|
#include <sys/vnode.h>
|
|
#include <sys/filio.h>
|
|
#include <i386/isa/isa_device.h>
|
|
#include <sys/alogio.h>
|
|
#include <sys/dataacq.h>
|
|
|
|
#include "opt_devfs.h"
|
|
#ifdef DEVFS
|
|
#include <sys/devfsext.h>
|
|
#endif
|
|
|
|
/* Local Defines */
|
|
|
|
/* Tests have shown that increasing the fifo size
|
|
* beyond 64 entries for this particular piece of hardware is
|
|
* unproductive */
|
|
|
|
#ifdef ALOG_FIFOSIZE
|
|
#define FIFOSIZE ALOG_FIFOSIZE
|
|
#else
|
|
#define FIFOSIZE 64
|
|
#endif
|
|
|
|
#ifdef ALOG_FIFO_TRIGGER
|
|
#define DEFAULT_FIFO_TRIGGER ALOG_FIFO_TRIGGER
|
|
#else
|
|
#define DEFAULT_FIFO_TRIGGER 1
|
|
#endif
|
|
|
|
#ifdef ALOG_CHANNELS
|
|
#define NUMCHANNELS ALOG_CHANNELS
|
|
#else
|
|
#define NUMCHANNELS 128
|
|
#endif
|
|
|
|
#ifdef ALOG_TIMO
|
|
#define READTIMO ALOG_TIMO
|
|
#else
|
|
#define READTIMO (MAX_MICRO_PERIOD*NUMCHANNELS/500000*hz)
|
|
#endif
|
|
|
|
#define CDEV_MAJOR 86
|
|
#define NUMPORTS 8
|
|
#define MAXUNITS 2
|
|
#define NUMIMUXES 8
|
|
|
|
#define ADLOW 0x0
|
|
#define ADHIGH 0x1
|
|
#define STATUS 0x2
|
|
#define CNTR0 0x4
|
|
#define CNTR1 0x5
|
|
#define CNTR2 0x6
|
|
#define CNTRCNTRL 0x7
|
|
|
|
#define DEVFORMAT "alog%d%c%d"
|
|
#define CLOCK2FREQ 4.165
|
|
#define MIN_MICRO_PERIOD 25
|
|
#define MAX_MICRO_PERIOD (65535/CLOCK2FREQ*PRIMARY_STATES)
|
|
#define DEFAULT_MICRO_PERIOD MAX_MICRO_PERIOD
|
|
#define READMAXTRIG 0.75*FIFOSIZE
|
|
#define ALOGPRI PRIBIO
|
|
#define ALOGMSG "alogio"
|
|
|
|
#define PRIMARY_STATES 2 /* Setup and conversion are clock tick consuming */
|
|
#define STATE_SETUP 0
|
|
#define STATE_CONVERT 1
|
|
#define STATE_READ 2
|
|
|
|
/* Notes on interrupt driven A/D conversion:
|
|
* On the AIO8-P, interrupt driven conversion (the only type supported by this
|
|
* driver) is facilitated through 8253 timer #2. In order for interrrupts to
|
|
* be generated you must connect line 6 to line 24 (counter 2 output to
|
|
* interrupt input) and line 23 to line 29 (counter 2 gate to +5VDC).
|
|
* Due to the design of the AIO8-P this precludes the use of programmable
|
|
* gain control.
|
|
*/
|
|
|
|
/* mode bits for the status register */
|
|
|
|
#define EOC 0x80
|
|
#define IEN 0x08
|
|
#define IMUXMASK 0x07
|
|
#define EMUXMASK 0xf0
|
|
|
|
/* mode bits for counter controller */
|
|
|
|
#define LD2MODE4 0xb8
|
|
|
|
/* Minor allocations:
|
|
* UCCCCMMM
|
|
* U: board unit (0-1)
|
|
* CCCC: external multiplexer channel (0-15) (on AT-16P units)
|
|
* MMM: internal multiplexer channel (0-7) (on AIO8-P card)
|
|
*/
|
|
|
|
#define UNIT(dev) ((minor(dev) & 0x80) >> 7)
|
|
#define CHANNEL(dev) (minor(dev) & 0x7f)
|
|
#define EMUX(chan) ((chan & 0x78) >> 3)
|
|
#define EMUXMAKE(chan) ((chan & 0x78) << 1)
|
|
#define IMUX(chan) (chan & 0x07)
|
|
#define LMINOR(unit, chan) ((unit << 7)+chan)
|
|
|
|
/* port statuses */
|
|
|
|
#define STATUS_UNUSED 0
|
|
#define STATUS_INUSE 1
|
|
#define STATUS_STOPPED 2
|
|
#define STATUS_INIT 3
|
|
|
|
/* Type definitions */
|
|
|
|
typedef struct
|
|
{
|
|
short status; /* the status of this chan */
|
|
struct selinfo readpoll; /* the poll() info */
|
|
u_short fifo[FIFOSIZE]; /* fifo for this chan */
|
|
int fifostart, fifoend; /* the ptrs showing where info is stored in fifo */
|
|
int fifosize, fifotrig; /* the current and trigger size of the fifo */
|
|
void *devfs_token; /* the devfs token for this chan */
|
|
int nextchan;
|
|
} talog_chan;
|
|
|
|
typedef struct
|
|
{
|
|
struct isa_device *isaunit; /* ptr to isa device information */
|
|
talog_chan chan[NUMCHANNELS]; /* the device nodes */
|
|
int curchan; /* the current chan being intr handled */
|
|
int firstchan; /* the first chan to go to in list */
|
|
int state; /* is the node in setup or convert mode */
|
|
long microperiod; /* current microsecond period setting */
|
|
u_char perlo, perhi; /* current values to send to clock 2 after every intr */
|
|
|
|
} talog_unit;
|
|
|
|
/* Function Prototypes */
|
|
|
|
static int alog_probe (struct isa_device *idp); /* Check for alog board */
|
|
static int alog_attach (struct isa_device *idp); /* Take alog board */
|
|
static int sync_clock2 (int unit, long period); /* setup clock 2 period */
|
|
static int putfifo (talog_chan *pchan, u_short fifoent);
|
|
static int alog_open (dev_t dev, int oflags, int devtype, struct proc *p);
|
|
static int alog_close (dev_t dev, int fflag, int devtype, struct proc *p);
|
|
static int alog_ioctl (dev_t dev, u_long cmd, caddr_t data,
|
|
int fflag, struct proc *p);
|
|
static int alog_read (dev_t dev, struct uio *uio, int ioflag);
|
|
static int alog_poll (dev_t dev, int events, struct proc *p);
|
|
|
|
/* Global Data */
|
|
|
|
static int alog_devsw_installed = 0; /* Protect against reinit multiunit */
|
|
static talog_unit *alog_unit[NALOG]; /* data structs for each unit */
|
|
|
|
/* Character device switching structure */
|
|
static struct cdevsw alog_cdevsw = { alog_open, alog_close, alog_read,
|
|
nowrite, alog_ioctl, nostop, noreset,
|
|
nodevtotty, alog_poll, nommap,
|
|
nostrategy, "alog", NULL, -1 };
|
|
|
|
/* Structure expected to tell how to probe and attach the driver
|
|
* Must be published externally (cannot be static) */
|
|
struct isa_driver alogdriver = { alog_probe, alog_attach, "alog", 0 };
|
|
|
|
|
|
/* handle the ioctls */
|
|
static int alog_ioctl (dev_t dev, u_long cmd, caddr_t data,
|
|
int fflag, struct proc *p)
|
|
{
|
|
int unit = UNIT(dev);
|
|
int chan = CHANNEL(dev);
|
|
talog_unit *info = alog_unit[unit];
|
|
int s;
|
|
|
|
switch (cmd)
|
|
{
|
|
case FIONBIO: return 0; /* this allows for non-blocking ioctls */
|
|
|
|
case AD_NCHANS_GET: *(int *)data = NUMCHANNELS;
|
|
return 0;
|
|
case AD_FIFOSIZE_GET: *(int *)data = FIFOSIZE;
|
|
return 0;
|
|
|
|
case AD_FIFO_TRIGGER_GET: s = spltty();
|
|
*(int *)data = info->chan[chan].fifotrig;
|
|
splx(s);
|
|
return 0;
|
|
|
|
case AD_FIFO_TRIGGER_SET:
|
|
s = spltty();
|
|
if ((*(int *)data < 1) || (*(int *)data > FIFOSIZE))
|
|
{
|
|
splx(s);
|
|
return EPERM;
|
|
}
|
|
info->chan[chan].fifotrig = *(int *)data;
|
|
splx(s);
|
|
return 0;
|
|
|
|
case AD_STOP: s = spltty();
|
|
info->chan[chan].status = STATUS_STOPPED;
|
|
splx(s);
|
|
return 0;
|
|
|
|
case AD_START: s = spltty();
|
|
info->chan[chan].status = STATUS_INUSE;
|
|
splx(s);
|
|
return 0;
|
|
|
|
case AD_MICRO_PERIOD_SET:
|
|
s = spltty();
|
|
if (sync_clock2 (unit, *(long *) data))
|
|
{
|
|
splx(s);
|
|
return EPERM;
|
|
}
|
|
splx(s);
|
|
return 0;
|
|
|
|
case AD_MICRO_PERIOD_GET: s = spltty();
|
|
*(long *)data = info->microperiod;
|
|
splx(s);
|
|
return 0;
|
|
|
|
}
|
|
|
|
return ENOTTY;
|
|
}
|
|
|
|
|
|
/* handle poll() based read polling */
|
|
static int alog_poll (dev_t dev, int events, struct proc *p)
|
|
{
|
|
int unit = UNIT(dev);
|
|
int chan = CHANNEL(dev);
|
|
talog_unit *info = alog_unit[unit];
|
|
int s;
|
|
|
|
s = spltty();
|
|
if (events & (POLLIN | POLLRDNORM)) /* if polling for any/normal data */
|
|
if (info->chan[chan].fifosize >= info->chan[chan].fifotrig)
|
|
{
|
|
splx(s);
|
|
|
|
return events & (POLLIN | POLLRDNORM); /* ready for any/read */
|
|
}
|
|
else
|
|
{
|
|
/* record this request */
|
|
selrecord (p, &(info->chan[chan].readpoll));
|
|
splx(s);
|
|
return 0; /* not ready, yet */
|
|
}
|
|
|
|
splx(s);
|
|
return 0; /* not ready (any I never will be) */
|
|
}
|
|
|
|
|
|
/* how to read from the board */
|
|
static int alog_read (dev_t dev, struct uio *uio, int ioflag)
|
|
{
|
|
int unit = UNIT(dev);
|
|
int chan = CHANNEL(dev);
|
|
talog_unit *info = alog_unit[unit];
|
|
int s, oldtrig, toread, err = 0;
|
|
|
|
s = spltty();
|
|
|
|
oldtrig = info->chan[chan].fifotrig; /* save official trigger value */
|
|
while (uio->uio_resid >= sizeof(u_short)) /* while uio has space */
|
|
{
|
|
if (!info->chan[chan].fifosize) /* if we have an empty fifo */
|
|
{
|
|
if (ioflag & IO_NDELAY) /* exit if we are non-blocking */
|
|
{ err = EWOULDBLOCK;
|
|
break;
|
|
}
|
|
/* Start filling fifo on first blocking read */
|
|
if (info->chan[chan].status == STATUS_INIT)
|
|
info->chan[chan].status = STATUS_INUSE;
|
|
/* temporarily adjust the fifo trigger to be optimal size */
|
|
info->chan[chan].fifotrig =
|
|
min (READMAXTRIG, uio->uio_resid / sizeof(u_short));
|
|
/* lets sleep until we have some io available or timeout */
|
|
err = tsleep (&(info->chan[chan].fifo), ALOGPRI | PCATCH, ALOGMSG,
|
|
info->chan[chan].fifotrig*READTIMO);
|
|
if (err == EWOULDBLOCK)
|
|
{ printf (DEVFORMAT ": read timeout\n", unit,
|
|
'a'+EMUX(chan), IMUX(chan));
|
|
}
|
|
if (err == ERESTART) err = EINTR; /* don't know how to restart */
|
|
if (err) break; /* exit if any kind of error or signal */
|
|
}
|
|
|
|
/* ok, now if we got here there is something to read from the fifo */
|
|
|
|
/* calculate how many entries we can read out from the fifostart
|
|
* pointer */
|
|
toread = min (uio->uio_resid / sizeof(u_short),
|
|
min (info->chan[chan].fifosize,
|
|
FIFOSIZE - info->chan[chan].fifostart));
|
|
/* perform the move, if there is an error then exit */
|
|
if (err = uiomove((caddr_t)
|
|
&(info->chan[chan].fifo[info->chan[chan].fifostart]),
|
|
toread * sizeof(u_short), uio)) break;
|
|
info->chan[chan].fifosize -= toread; /* fifo this much smaller */
|
|
info->chan[chan].fifostart += toread; /* we got this many more */
|
|
if (info->chan[chan].fifostart == FIFOSIZE)
|
|
info->chan[chan].fifostart = 0; /* wrap around fifostart */
|
|
|
|
}
|
|
info->chan[chan].fifotrig = oldtrig; /* restore trigger changes */
|
|
splx(s);
|
|
return err;
|
|
}
|
|
|
|
|
|
/* open a channel */
|
|
static int alog_open (dev_t dev, int oflags, int devtype, struct proc *p)
|
|
{
|
|
int unit = UNIT(dev); /* get unit no */
|
|
int chan = CHANNEL(dev); /* get channel no */
|
|
talog_unit *info;
|
|
int s; /* priority */
|
|
int cur;
|
|
|
|
if ((unit >= NALOG) || (unit >= MAXUNITS) || (chan >= NUMCHANNELS))
|
|
return ENXIO; /* unit and channel no ok ? */
|
|
if (!alog_unit[unit]) return ENXIO; /* unit attached */
|
|
info = alog_unit[unit]; /* ok, this is valid now */
|
|
|
|
if (info->chan[chan].status) return EBUSY; /* channel busy */
|
|
if (oflags & FREAD)
|
|
{
|
|
s=spltty();
|
|
info->chan[chan].status = STATUS_INIT; /* channel open, read waiting */
|
|
info->chan[chan].fifostart = info->chan[chan].fifoend =
|
|
info->chan[chan].fifosize = 0;/* fifo empty */
|
|
info->chan[chan].fifotrig = DEFAULT_FIFO_TRIGGER;
|
|
if (info->firstchan < 0) /* if empty chain */
|
|
{
|
|
info->firstchan = info->curchan = chan; /* rev up the list */
|
|
info->chan[chan].nextchan = -1; /* end of the list */
|
|
}
|
|
else /* non empty list must insert */
|
|
{
|
|
if (chan < info->firstchan) /* this one must become first in list */
|
|
{
|
|
info->chan[chan].nextchan = info->firstchan;
|
|
info->firstchan = chan;
|
|
}
|
|
else /* insert this one as second - last in chan list */
|
|
{
|
|
cur = info->firstchan;
|
|
|
|
/* traverse list as long as cur is less than chan and cur is
|
|
* not last in list */
|
|
while ((info->chan[cur].nextchan < chan) &&
|
|
(info->chan[cur].nextchan >= 0))
|
|
cur = info->chan[cur].nextchan;
|
|
|
|
/* now cur should point to the entry right before yours */
|
|
info->chan[chan].nextchan = info->chan[cur].nextchan;
|
|
info->chan[cur].nextchan = chan; /* insert yours in */
|
|
}
|
|
}
|
|
splx(s);
|
|
return 0; /* open successful */
|
|
}
|
|
return EPERM; /* this is a read only device */
|
|
}
|
|
|
|
|
|
/* close a channel */
|
|
static int alog_close (dev_t dev, int fflag, int devtype, struct proc *p)
|
|
{
|
|
int unit = UNIT(dev);
|
|
int chan = CHANNEL(dev);
|
|
talog_unit *info = alog_unit[unit];
|
|
int s;
|
|
int cur;
|
|
|
|
s = spltty();
|
|
info->chan[chan].status = STATUS_UNUSED;
|
|
|
|
/* what if we are in the middle of a conversion ?
|
|
* then smoothly get us out of it: */
|
|
if (info->curchan == chan)
|
|
{ /* if we are last in list set curchan to first in list */
|
|
if ((info->curchan = info->chan[chan].nextchan) < 0)
|
|
info->curchan = info->firstchan;
|
|
|
|
info->state = STATE_SETUP;
|
|
}
|
|
|
|
/* if this is the first channel, then make the second channel the first
|
|
* channel (note that if this is also the only channel firstchan becomes
|
|
* -1 and so the list is marked as empty */
|
|
|
|
if (chan == info->firstchan)
|
|
info->firstchan = info->chan[chan].nextchan;
|
|
else /* ok, so there must be at least 2 channels (and it is not the first) */
|
|
{
|
|
cur = info->firstchan;
|
|
|
|
/* find the entry before it (which must exist if you are closing) */
|
|
while (info->chan[cur].nextchan < chan)
|
|
cur = info->chan[cur].nextchan;
|
|
/* at this point we must have the entry before ours */
|
|
info->chan[cur].nextchan = info->chan[chan].nextchan; /* give our link */
|
|
|
|
}
|
|
|
|
splx(s);
|
|
|
|
return 0; /* close always successful */
|
|
}
|
|
|
|
|
|
/* The probing routine - returns number of bytes needed */
|
|
static int alog_probe (struct isa_device *idp)
|
|
{
|
|
int unit = idp->id_unit; /* this device unit number */
|
|
int iobase = idp->id_iobase; /* the base address of the unit */
|
|
int addr;
|
|
|
|
if ((unit < 0) || (unit >= NALOG) || (unit >= MAXUNITS))
|
|
{
|
|
printf ("alog: invalid unit number (%d)\n", unit);
|
|
return 0;
|
|
}
|
|
|
|
/* the unit number is ok, lets check if used */
|
|
if (alog_unit[unit])
|
|
{
|
|
printf ("alog: unit (%d) already attached\n", unit);
|
|
return 0;
|
|
}
|
|
|
|
if (inb (iobase+STATUS) & EOC) return 0; /* End of conv bit should be 0 */
|
|
for (addr=0; addr<NUMIMUXES; addr++)
|
|
{
|
|
outb (iobase+STATUS, EMUXMASK|addr);/* output ones to upper nibbl+addr */
|
|
/* get back a zero in MSB and the addr where you put it */
|
|
if ((inb (iobase+STATUS) & (EOC|IMUXMASK)) != addr) return 0;
|
|
}
|
|
|
|
return NUMPORTS; /* this device needs this many ports */
|
|
}
|
|
|
|
|
|
/* setup the info structure correctly for reloading clock 2 after interrupt */
|
|
static int sync_clock2 (int unit, long period)
|
|
{
|
|
int clockper;
|
|
talog_unit *info = alog_unit[unit];
|
|
|
|
if ((period > MAX_MICRO_PERIOD) || (period < MIN_MICRO_PERIOD))
|
|
return -1; /* error period too long */
|
|
info->microperiod = period; /* record the period */
|
|
clockper = (CLOCK2FREQ * period) / PRIMARY_STATES;
|
|
info->perlo = clockper & 0xff; /* least sig byte of clock period */
|
|
info->perhi = ((clockper & 0xff00) >> 8); /* most sig byte of clock period */
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* The attachment routine - returns true on success */
|
|
static int alog_attach (struct isa_device *idp)
|
|
{
|
|
int unit = idp->id_unit; /* this device unit number */
|
|
int iobase = idp->id_iobase; /* the base address of the unit */
|
|
talog_unit *info; /* pointer to driver specific info for unit */
|
|
int chan; /* the channel used for creating devfs nodes */
|
|
|
|
if (!(info = malloc(sizeof(*info), M_DEVBUF, M_NOWAIT)))
|
|
{
|
|
printf ("alog%d: cannot allocate driver storage\n", unit);
|
|
return 0;
|
|
}
|
|
alog_unit[unit] = info; /* make sure to save the pointer */
|
|
bzero (info, sizeof(*info)); /* clear info structure to all false */
|
|
info->isaunit = idp; /* store ptr to isa device information */
|
|
sync_clock2 (unit, DEFAULT_MICRO_PERIOD); /* setup perlo and perhi */
|
|
info->firstchan = -1; /* channel lists are empty */
|
|
|
|
/* insert devfs nodes */
|
|
|
|
#ifdef DEVFS
|
|
for (chan=0; chan<NUMCHANNELS; chan++)
|
|
info->chan[chan].devfs_token =
|
|
devfs_add_devswf(&alog_cdevsw, LMINOR(unit, chan), DV_CHR,
|
|
UID_ROOT, GID_WHEEL, 0400, DEVFORMAT,
|
|
unit, 'a'+EMUX(chan), IMUX(chan));
|
|
#endif
|
|
|
|
printf ("alog%d: %d channels, %d bytes/FIFO, %d entry trigger\n",
|
|
unit, NUMCHANNELS, FIFOSIZE*sizeof(u_short),
|
|
DEFAULT_FIFO_TRIGGER);
|
|
alogintr (unit); /* start the periodic interrupting process */
|
|
return 1; /* obviously successful */
|
|
}
|
|
|
|
|
|
/* Unit interrupt handling routine (interrupts generated by clock 2) */
|
|
void alogintr (int unit)
|
|
{
|
|
talog_unit *info = alog_unit[unit];
|
|
int iobase = info->isaunit->id_iobase;
|
|
u_short fifoent;
|
|
|
|
|
|
if (info->firstchan >= 0) /* ? is there even a chan list to traverse */
|
|
switch (info->state)
|
|
{
|
|
case STATE_READ:
|
|
if (info->chan[info->curchan].status == STATUS_INUSE)
|
|
{
|
|
if (inb (iobase+STATUS) & EOC) /* check that conversion finished */
|
|
printf (DEVFORMAT ": incomplete conversion\n", unit,
|
|
'a'+EMUX(info->curchan), IMUX(info->curchan));
|
|
else /* conversion is finished (should always be) */
|
|
{
|
|
fifoent = (inb (iobase+ADHIGH) << 8) +
|
|
inb (iobase+ADLOW);
|
|
if (putfifo(&(info->chan[info->curchan]), fifoent))
|
|
{
|
|
printf (DEVFORMAT ": fifo overflow\n", unit,
|
|
'a'+EMUX(info->curchan), IMUX(info->curchan));
|
|
}
|
|
if (info->chan[info->curchan].fifosize >=
|
|
info->chan[info->curchan].fifotrig)
|
|
{
|
|
/* if we've reached trigger levels */
|
|
selwakeup (&(info->chan[info->curchan].readpoll));
|
|
wakeup (&(info->chan[info->curchan].fifo));
|
|
}
|
|
}
|
|
}
|
|
/* goto setup state for next channel on list */
|
|
if ((info->curchan = info->chan[info->curchan].nextchan) < 0)
|
|
info->curchan = info->firstchan;
|
|
/* notice lack of break here this implys a STATE_SETUP */
|
|
case STATE_SETUP: /* set the muxes and let them settle */
|
|
#if NUMCHANNELS > NUMIMUXES /* only do this if using external muxes */
|
|
outb (iobase+STATUS,
|
|
EMUXMAKE(info->curchan) | IMUX(info->curchan) | IEN);
|
|
info->state = STATE_CONVERT;
|
|
break;
|
|
#endif
|
|
case STATE_CONVERT:
|
|
outb (iobase+STATUS,
|
|
EMUXMAKE(info->curchan) | IMUX(info->curchan) | IEN);
|
|
outb (iobase+ADHIGH, 0); /* start the conversion */
|
|
info->state = STATE_READ;
|
|
break;
|
|
}
|
|
else /* this is kind of like an idle mode */
|
|
{
|
|
outb (iobase+STATUS, IEN); /* no list keep getting interrupts though */
|
|
/* since we have no open channels spin clock rate down to
|
|
* minimum to save interrupt overhead */
|
|
outb (iobase+CNTRCNTRL, LD2MODE4); /* counter 2 to mode 4 strobe */
|
|
outb (iobase+CNTR2, 0xff); /* longest period we can generate */
|
|
outb (iobase+CNTR2, 0xff);
|
|
return;
|
|
}
|
|
outb (iobase+CNTRCNTRL, LD2MODE4); /* counter 2 to mode 4 strobe */
|
|
outb (iobase+CNTR2, info->perlo); /* low part of the period count */
|
|
outb (iobase+CNTR2, info->perhi); /* high part of the period count */
|
|
}
|
|
|
|
|
|
/* this will put an entry in fifo, returns 1 if the first item in
|
|
* fifo was wiped (overflow) or 0 if everything went fine */
|
|
static int putfifo (talog_chan *pchan, u_short fifoent)
|
|
{
|
|
pchan->fifo[pchan->fifoend] = fifoent; /* insert the entry in */
|
|
pchan->fifoend++; /* one more in fifo */
|
|
if (pchan->fifoend == FIFOSIZE) pchan->fifoend = 0; /* wrap around */
|
|
/* note: I did intend to write over the oldest entry on overflow */
|
|
if (pchan->fifosize == FIFOSIZE) /* overflowing state already */
|
|
{
|
|
pchan->fifostart++;
|
|
if (pchan->fifostart == FIFOSIZE) pchan->fifostart = 0;
|
|
return 1; /* we overflowed */
|
|
}
|
|
pchan->fifosize++; /* actually one bigger, else same size */
|
|
return 0; /* went in just fine */
|
|
}
|
|
|
|
|
|
/* Driver initialization */
|
|
static void alog_drvinit (void *unused)
|
|
{
|
|
dev_t dev; /* Type for holding device major/minor numbers (int) */
|
|
|
|
if (!alog_devsw_installed)
|
|
{
|
|
dev = makedev (CDEV_MAJOR, 0); /* description of device major */
|
|
cdevsw_add (&dev, &alog_cdevsw, NULL); /* put driver in cdev table */
|
|
alog_devsw_installed=1;
|
|
}
|
|
}
|
|
|
|
/* System initialization call instance */
|
|
|
|
SYSINIT (alogdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE+CDEV_MAJOR,
|
|
alog_drvinit,NULL);
|
|
|
|
#endif
|