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_ RU.UNIX.BSD (2:5077/15.22) _____________________________________ RU.UNIX.BSD _
 From : vadik likholetov                    2:5030/266      Wed 30 Dec 98 17:06 
 Subj : /dev/io или управление lptом                                            
________________________________________________________________________________
кто-то там просил -- возьмите осмысленный драйвер,  с которого можно 
начать ;-)

/*
 * Power controller (c) 1998, vadik likholetov vadik@sensi.org Hardware by
 * Alexandr Priomov, alexandr@sensi.org
 */

#include "pwc.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/conf.h>
#include <sys/uio.h>


#include <i386/isa/isa.h>
#include <i386/isa/isa_device.h>
#include <i386/isa/lptreg.h>

static struct pwc_softc {
  int             sc_port;
  short           sc_state;
  int             hw_state;
}               pwc_sc[NPWC];

#define TASK_SIZE 12

#define DEFAULT 0     /* default state for device */
#define OPEN (1<<0)    /* device is open */
#define OBUSY (1<<1)   /* doing output */
#define OPENDING (1<<2)    /* pending output */


static int      pwc_probe(struct isa_device * dvp);
static int      pwc_attach(struct isa_device * isdp);

struct isa_driver pwcdriver = {
  pwc_probe, pwc_attach, "pwc"
};


static d_open_t pwc_open;
static d_close_t pwc_close;
static d_write_t pwc_write;


#define CDEV_MAJOR 220

static struct cdevsw pwc_cdevsw =
{pwc_open, pwc_close, noread, pwc_write,
  noioctl, nullstop, nullreset, nodevtotty,
seltrue, nommap, nostrat, "pwc", NULL, -1};

int 
pwc_probe(struct isa_device * dvp)
{
  /* TODO -- test hardware for presence */
  return 1;
}

int 
pwc_attach(struct isa_device * isdp)
{
  struct pwc_softc *sc;
  int             unit = isdp->id_unit;

  sc = pwc_sc + unit;
  sc->sc_port = isdp->id_iobase;
  sc->sc_state = DEFAULT;
  outb(sc->sc_port, 0);
  outb(sc->sc_port + lpt_control, 0);
  return 1;
}


static int 
pwc_open(dev_t dev, int flags, int fmt, struct proc * p)
{
  struct pwc_softc *sc;

  u_int           unit = minor(dev);

  sc = pwc_sc + unit;

  if ((unit >= NPWC) || (sc->sc_port == 0))
   return ENXIO;

  if (sc->sc_state != DEFAULT)
   return EBUSY;

  return 0;
}

static int 
pwc_close(dev_t dev, int flags, int fmt, struct proc * p)
{
  struct pwc_softc *sc = pwc_sc + minor(dev);

  sc->sc_state &= ~OPEN;
  while (sc->sc_state & OBUSY)
   if (tsleep((caddr_t) sc, PZERO | PCATCH, "pwcclose", hz) != EWOULDBLOCK)
      break;

  sc->sc_state = DEFAULT;

  return 0;
}

static int 
pwc_write(dev_t dev, struct uio * uio, int ioflag)
{
  struct pwc_softc *sc = pwc_sc + minor(dev);
  char            buffer[TASK_SIZE];
  int             port = sc->sc_port;
  int             s;
  int             ret;
  int             i, j, d;

  if (uio->uio_resid != TASK_SIZE)
   return EOPNOTSUPP;

  s = spltty();
  if (sc->sc_state & OBUSY)
   return EBUSY;

  sc->sc_state |= OBUSY;
  splx(s);

  /* output goes there */

  uiomove(buffer, TASK_SIZE, uio);

  if (!(inb(port + lpt_status) & ~LPS_NACK)) {
   printf("pwc%d: no power on device\n", minor(dev));
   ret = EIO;
   goto gout;
  }
#define NTRIES 10
  for (i = 0; i < TASK_SIZE; i++) {
   for (j = 0; j < NTRIES; j++)
      if ((inb(port + lpt_status) & LPS_NBSY))
       break;
      else
       DELAY(1);
   if (j == NTRIES) {
      printf("pwc%d: timeout(1) waiting for ~BSY (%x)\n",
minor(dev),inb(port+lpt_status));
      ret = EIO;
      goto gout;
   }
   d = buffer[i] == '1' ? 1 : 0;

   if (i > 3 && i < 8)
      i ^= 1;

   outb(port + lpt_data, d);
   outb(port + lpt_control, LPC_STB);
   DELAY(1);  /* ??? */
   outb(port + lpt_control, 0);
  }

  for (j = 0; j < NTRIES; j++)
   if (inb(port + lpt_status) & LPS_NBSY)
      break;
   else
      DELAY(1);

  if (j == NTRIES) {
   printf("pwc%d: timeout(2) waiting for ~BSY\n", minor(dev));
   ret = EIO;
   goto gout;
  }
  ret = 0;
gout:
  s = spltty();
  sc->sc_state &= ~OBUSY;

#if 0
  if (sc->sc_state & OPENDING)
#endif
   wakeup((caddr_t) sc);

  splx(s);
  return ret;
}


static          pwc_devsw_installed = 0;

static void 
pwc_drvinit(void *unused)
{
  dev_t           dev;

  if (!pwc_devsw_installed) {
   dev = makedev(CDEV_MAJOR, 0);
   cdevsw_add(&dev, &pwc_cdevsw, NULL);
   pwc_devsw_installed = 1;
  }
}

SYSINIT(pwcdev, SI_SUB_DRIVERS, SI_ORDER_MIDDLE + CDEV_MAJOR, pwc_drvinit,
NULL)

-- 
vadik likholetov
--- ifmail v.2.12.os.sensi
 * Origin: /kernel: last message repeated 2 times (2:5030/266@fidonet)



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