FreeBSD/Linux Kernel Cross Reference
sys/dev/kbd/atkbdc.c

     /*-
      * Copyright (c) 1996-1999
      * Kazutaka YOKOTA (yokota@zodiac.mech.utsunomiya-u.ac.jp)
      * 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.
     * 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
     *
     * $FreeBSD$
     * from kbdio.c,v 1.13 1998/09/25 11:55:46 yokota Exp
     */
    
    #include "atkbdc.h"
    #include "opt_kbd.h"
    
    #include <sys/param.h>
    #include <sys/systm.h>
    #include <sys/kernel.h>
    #include <sys/malloc.h>
    #include <sys/syslog.h>
    
    #include <machine/clock.h>
    
    #include <dev/kbd/atkbdcreg.h>
    
    #ifndef __i386__
    #include <isa/isareg.h>
    #else
    #include <i386/isa/isa.h>
    #endif
    
    /* constants */
    
    #define MAXKBDC         MAX(NATKBDC, 1)
    
    /* macros */
    
    #ifndef MAX
    #define MAX(x, y)       ((x) > (y) ? (x) : (y))
    #endif
    
    #define kbdcp(p)        ((atkbdc_softc_t *)(p))
    #define nextq(i)        (((i) + 1) % KBDQ_BUFSIZE)
    #define availq(q)       ((q)->head != (q)->tail)
    #if KBDIO_DEBUG >= 2
    #define emptyq(q)       ((q)->tail = (q)->head = (q)->qcount = 0)
    #else
    #define emptyq(q)       ((q)->tail = (q)->head = 0)
    #endif
    
    /* local variables */
    
    /*
     * We always need at least one copy of the kbdc_softc struct for the
     * low-level console.  As the low-level console accesses the keyboard
     * controller before kbdc, and all other devices, is probed, we
     * statically allocate one entry. XXX
     */
    static atkbdc_softc_t default_kbdc;
    static atkbdc_softc_t *atkbdc_softc[MAXKBDC] = { &default_kbdc };
    
    static int verbose = KBDIO_DEBUG;
    
    /* function prototypes */
    
    static int atkbdc_setup(atkbdc_softc_t *sc, int port);
    static int addq(kqueue *q, int c);
    static int removeq(kqueue *q);
    static int wait_while_controller_busy(atkbdc_softc_t *kbdc);
    static int wait_for_data(atkbdc_softc_t *kbdc);
    static int wait_for_kbd_data(atkbdc_softc_t *kbdc);
    static int wait_for_kbd_ack(atkbdc_softc_t *kbdc);
    static int wait_for_aux_data(atkbdc_softc_t *kbdc);
    static int wait_for_aux_ack(atkbdc_softc_t *kbdc);
    
    #if NATKBDC > 0
    
    atkbdc_softc_t
   *atkbdc_get_softc(int unit)
   {
           atkbdc_softc_t *sc;
   
           if (unit >= sizeof(atkbdc_softc)/sizeof(atkbdc_softc[0]))
                   return NULL;
           sc = atkbdc_softc[unit];
           if (sc == NULL) {
                   sc = atkbdc_softc[unit]
                      = malloc(sizeof(*sc), M_DEVBUF, M_NOWAIT);
                   if (sc == NULL)
                           return NULL;
                   bzero(sc, sizeof(*sc));
                   sc->port = -1;  /* XXX */
           }
           return sc;
   }
   
   int
   atkbdc_probe_unit(atkbdc_softc_t *sc, int unit, int port)
   {
           return atkbdc_setup(sc, port);
   }
   
   #endif /* NATKBDC > 0 */
   
   /* the backdoor to the keyboard controller! XXX */
   int
   atkbdc_configure(void)
   {
           return atkbdc_setup(atkbdc_softc[0], -1);
   }
   
   static int
   atkbdc_setup(atkbdc_softc_t *sc, int port)
   {
           if (port <= 0)
                   port = IO_KBD;
   
           if (sc->port <= 0) {
               sc->command_byte = -1;
               sc->command_mask = 0;
               sc->lock = FALSE;
               sc->kbd.head = sc->kbd.tail = 0;
               sc->aux.head = sc->aux.tail = 0;
   #if KBDIO_DEBUG >= 2
               sc->kbd.call_count = 0;
               sc->kbd.qcount = sc->kbd.max_qcount = 0;
               sc->aux.call_count = 0;
               sc->aux.qcount = sc->aux.max_qcount = 0;
   #endif
           }
           sc->port = port;        /* may override the previous value */
           return 0;
   }
   
   /* associate a port number with a KBDC */
   
   KBDC 
   kbdc_open(int port)
   {
       int s;
       int i;
   
       if (port <= 0)
           port = IO_KBD;
   
       s = spltty();
       for (i = 0; i < sizeof(atkbdc_softc)/sizeof(atkbdc_softc[0]); ++i) {
           if (atkbdc_softc[i] == NULL)
               continue;
           if (atkbdc_softc[i]->port == port) {
               splx(s);
               return (KBDC)atkbdc_softc[i];
           }
           if (atkbdc_softc[i]->port <= 0) {
               if (atkbdc_setup(atkbdc_softc[i], port))
                   break;
               splx(s);
               return (KBDC)atkbdc_softc[i];
           }
       }
       splx(s);
       return NULL;
   }
   
   /*
    * I/O access arbitration in `kbdio'
    *
    * The `kbdio' module uses a simplistic convention to arbitrate
    * I/O access to the controller/keyboard/mouse. The convention requires
    * close cooperation of the calling device driver.
    *
    * The device driver which utilizes the `kbdio' module are assumed to
    * have the following set of routines.
    *    a. An interrupt handler (the bottom half of the driver).
    *    b. Timeout routines which may briefly polls the keyboard controller.
    *    c. Routines outside interrupt context (the top half of the driver).
    * They should follow the rules below:
    *    1. The interrupt handler may assume that it always has full access 
    *       to the controller/keyboard/mouse.
    *    2. The other routines must issue `spltty()' if they wish to 
    *       prevent the interrupt handler from accessing 
    *       the controller/keyboard/mouse.
    *    3. The timeout routines and the top half routines of the device driver
    *       arbitrate I/O access by observing the lock flag in `kbdio'.
    *       The flag is manipulated via `kbdc_lock()'; when one wants to
    *       perform I/O, call `kbdc_lock(kbdc, TRUE)' and proceed only if
    *       the call returns with TRUE. Otherwise the caller must back off.
    *       Call `kbdc_lock(kbdc, FALSE)' when necessary I/O operaion
    *       is finished. This mechanism does not prevent the interrupt 
    *       handler from being invoked at any time and carrying out I/O.
    *       Therefore, `spltty()' must be strategically placed in the device
    *       driver code. Also note that the timeout routine may interrupt
    *       `kbdc_lock()' called by the top half of the driver, but this
    *       interruption is OK so long as the timeout routine observes the
    *       the rule 4 below.
    *    4. The interrupt and timeout routines should not extend I/O operation
    *       across more than one interrupt or timeout; they must complete
    *       necessary I/O operation within one invokation of the routine.
    *       This measns that if the timeout routine acquires the lock flag,
    *       it must reset the flag to FALSE before it returns.
    */
   
   /* set/reset polling lock */
   int 
   kbdc_lock(KBDC p, int lock)
   {
       int prevlock;
   
       prevlock = kbdcp(p)->lock;
       kbdcp(p)->lock = lock;
   
       return (prevlock != lock);
   }
   
   /* check if any data is waiting to be processed */
   int
   kbdc_data_ready(KBDC p)
   {
       return (availq(&kbdcp(p)->kbd) || availq(&kbdcp(p)->aux) 
           || (inb(kbdcp(p)->port + KBD_STATUS_PORT) & KBDS_ANY_BUFFER_FULL));
   }
   
   /* queuing functions */
   
   static int
   addq(kqueue *q, int c)
   {
       if (nextq(q->tail) != q->head) {
           q->q[q->tail] = c;
           q->tail = nextq(q->tail);
   #if KBDIO_DEBUG >= 2
           ++q->call_count;
           ++q->qcount;
           if (q->qcount > q->max_qcount)
               q->max_qcount = q->qcount;
   #endif
           return TRUE;
       }
       return FALSE;
   }
   
   static int
   removeq(kqueue *q)
   {
       int c;
   
       if (q->tail != q->head) {
           c = q->q[q->head];
           q->head = nextq(q->head);
   #if KBDIO_DEBUG >= 2
           --q->qcount;
   #endif
           return c;
       }
       return -1;
   }
   
   /* 
    * device I/O routines
    */
   static int
   wait_while_controller_busy(struct atkbdc_softc *kbdc)
   {
       /* CPU will stay inside the loop for 100msec at most */
       int retry = 5000;
       int port = kbdc->port;
       int f;
   
       while ((f = inb(port + KBD_STATUS_PORT)) & KBDS_INPUT_BUFFER_FULL) {
           if ((f & KBDS_BUFFER_FULL) == KBDS_KBD_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               addq(&kbdc->kbd, inb(port + KBD_DATA_PORT));
           } else if ((f & KBDS_BUFFER_FULL) == KBDS_AUX_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               addq(&kbdc->aux, inb(port + KBD_DATA_PORT));
           }
           DELAY(KBDC_DELAYTIME);
           if (--retry < 0)
               return FALSE;
       }
       return TRUE;
   }
   
   /*
    * wait for any data; whether it's from the controller, 
    * the keyboard, or the aux device.
    */
   static int
   wait_for_data(struct atkbdc_softc *kbdc)
   {
       /* CPU will stay inside the loop for 200msec at most */
       int retry = 10000;
       int port = kbdc->port;
       int f;
   
       while ((f = inb(port + KBD_STATUS_PORT) & KBDS_ANY_BUFFER_FULL) == 0) {
           DELAY(KBDC_DELAYTIME);
           if (--retry < 0)
               return 0;
       }
       DELAY(KBDD_DELAYTIME);
       return f;
   }
   
   /* wait for data from the keyboard */
   static int
   wait_for_kbd_data(struct atkbdc_softc *kbdc)
   {
       /* CPU will stay inside the loop for 200msec at most */
       int retry = 10000;
       int port = kbdc->port;
       int f;
   
       while ((f = inb(port + KBD_STATUS_PORT) & KBDS_BUFFER_FULL) 
               != KBDS_KBD_BUFFER_FULL) {
           if (f == KBDS_AUX_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               addq(&kbdc->aux, inb(port + KBD_DATA_PORT));
           }
           DELAY(KBDC_DELAYTIME);
           if (--retry < 0)
               return 0;
       }
       DELAY(KBDD_DELAYTIME);
       return f;
   }
   
   /* 
    * wait for an ACK(FAh), RESEND(FEh), or RESET_FAIL(FCh) from the keyboard.
    * queue anything else.
    */
   static int
   wait_for_kbd_ack(struct atkbdc_softc *kbdc)
   {
       /* CPU will stay inside the loop for 200msec at most */
       int retry = 10000;
       int port = kbdc->port;
       int f;
       int b;
   
       while (retry-- > 0) {
           if ((f = inb(port + KBD_STATUS_PORT)) & KBDS_ANY_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               b = inb(port + KBD_DATA_PORT);
               if ((f & KBDS_BUFFER_FULL) == KBDS_KBD_BUFFER_FULL) {
                   if ((b == KBD_ACK) || (b == KBD_RESEND) 
                       || (b == KBD_RESET_FAIL))
                       return b;
                   addq(&kbdc->kbd, b);
               } else if ((f & KBDS_BUFFER_FULL) == KBDS_AUX_BUFFER_FULL) {
                   addq(&kbdc->aux, b);
               }
           }
           DELAY(KBDC_DELAYTIME);
       }
       return -1;
   }
   
   /* wait for data from the aux device */
   static int
   wait_for_aux_data(struct atkbdc_softc *kbdc)
   {
       /* CPU will stay inside the loop for 200msec at most */
       int retry = 10000;
       int port = kbdc->port;
       int f;
   
       while ((f = inb(port + KBD_STATUS_PORT) & KBDS_BUFFER_FULL) 
               != KBDS_AUX_BUFFER_FULL) {
           if (f == KBDS_KBD_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               addq(&kbdc->kbd, inb(port + KBD_DATA_PORT));
           }
           DELAY(KBDC_DELAYTIME);
           if (--retry < 0)
               return 0;
       }
       DELAY(KBDD_DELAYTIME);
       return f;
   }
   
   /* 
    * wait for an ACK(FAh), RESEND(FEh), or RESET_FAIL(FCh) from the aux device.
    * queue anything else.
    */
   static int
   wait_for_aux_ack(struct atkbdc_softc *kbdc)
   {
       /* CPU will stay inside the loop for 200msec at most */
       int retry = 10000;
       int port = kbdc->port;
       int f;
       int b;
   
       while (retry-- > 0) {
           if ((f = inb(port + KBD_STATUS_PORT)) & KBDS_ANY_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               b = inb(port + KBD_DATA_PORT);
               if ((f & KBDS_BUFFER_FULL) == KBDS_AUX_BUFFER_FULL) {
                   if ((b == PSM_ACK) || (b == PSM_RESEND) 
                       || (b == PSM_RESET_FAIL))
                       return b;
                   addq(&kbdc->aux, b);
               } else if ((f & KBDS_BUFFER_FULL) == KBDS_KBD_BUFFER_FULL) {
                   addq(&kbdc->kbd, b);
               }
           }
           DELAY(KBDC_DELAYTIME);
       }
       return -1;
   }
   
   /* write a one byte command to the controller */
   int
   write_controller_command(KBDC p, int c)
   {
       if (!wait_while_controller_busy(kbdcp(p)))
           return FALSE;
       outb(kbdcp(p)->port + KBD_COMMAND_PORT, c);
       return TRUE;
   }
   
   /* write a one byte data to the controller */
   int
   write_controller_data(KBDC p, int c)
   {
       if (!wait_while_controller_busy(kbdcp(p)))
           return FALSE;
       outb(kbdcp(p)->port + KBD_DATA_PORT, c);
       return TRUE;
   }
   
   /* write a one byte keyboard command */
   int
   write_kbd_command(KBDC p, int c)
   {
       if (!wait_while_controller_busy(kbdcp(p)))
           return FALSE;
       outb(kbdcp(p)->port + KBD_DATA_PORT, c);
       return TRUE;
   }
   
   /* write a one byte auxiliary device command */
   int
   write_aux_command(KBDC p, int c)
   {
       if (!write_controller_command(p, KBDC_WRITE_TO_AUX))
           return FALSE;
       return write_controller_data(p, c);
   }
   
   /* send a command to the keyboard and wait for ACK */
   int
   send_kbd_command(KBDC p, int c)
   {
       int retry = KBD_MAXRETRY;
       int res = -1;
   
       while (retry-- > 0) {
           if (!write_kbd_command(p, c))
               continue;
           res = wait_for_kbd_ack(kbdcp(p));
           if (res == KBD_ACK)
               break;
       }
       return res;
   }
   
   /* send a command to the auxiliary device and wait for ACK */
   int
   send_aux_command(KBDC p, int c)
   {
       int retry = KBD_MAXRETRY;
       int res = -1;
   
       while (retry-- > 0) {
           if (!write_aux_command(p, c))
               continue;
           /*
            * FIXME: XXX
            * The aux device may have already sent one or two bytes of 
            * status data, when a command is received. It will immediately 
            * stop data transmission, thus, leaving an incomplete data 
            * packet in our buffer. We have to discard any unprocessed
            * data in order to remove such packets. Well, we may remove 
            * unprocessed, but necessary data byte as well... 
            */
           emptyq(&kbdcp(p)->aux);
           res = wait_for_aux_ack(kbdcp(p));
           if (res == PSM_ACK)
               break;
       }
       return res;
   }
   
   /* send a command and a data to the keyboard, wait for ACKs */
   int
   send_kbd_command_and_data(KBDC p, int c, int d)
   {
       int retry;
       int res = -1;
   
       for (retry = KBD_MAXRETRY; retry > 0; --retry) {
           if (!write_kbd_command(p, c))
               continue;
           res = wait_for_kbd_ack(kbdcp(p));
           if (res == KBD_ACK)
               break;
           else if (res != KBD_RESEND)
               return res;
       }
       if (retry <= 0)
           return res;
   
       for (retry = KBD_MAXRETRY, res = -1; retry > 0; --retry) {
           if (!write_kbd_command(p, d))
               continue;
           res = wait_for_kbd_ack(kbdcp(p));
           if (res != KBD_RESEND)
               break;
       }
       return res;
   }
   
   /* send a command and a data to the auxiliary device, wait for ACKs */
   int
   send_aux_command_and_data(KBDC p, int c, int d)
   {
       int retry;
       int res = -1;
   
       for (retry = KBD_MAXRETRY; retry > 0; --retry) {
           if (!write_aux_command(p, c))
               continue;
           emptyq(&kbdcp(p)->aux);
           res = wait_for_aux_ack(kbdcp(p));
           if (res == PSM_ACK)
               break;
           else if (res != PSM_RESEND)
               return res;
       }
       if (retry <= 0)
           return res;
   
       for (retry = KBD_MAXRETRY, res = -1; retry > 0; --retry) {
           if (!write_aux_command(p, d))
               continue;
           res = wait_for_aux_ack(kbdcp(p));
           if (res != PSM_RESEND)
               break;
       }
       return res;
   }
   
   /* 
    * read one byte from any source; whether from the controller,
    * the keyboard, or the aux device
    */
   int
   read_controller_data(KBDC p)
   {
       if (availq(&kbdcp(p)->kbd)) 
           return removeq(&kbdcp(p)->kbd);
       if (availq(&kbdcp(p)->aux)) 
           return removeq(&kbdcp(p)->aux);
       if (!wait_for_data(kbdcp(p)))
           return -1;              /* timeout */
       return inb(kbdcp(p)->port + KBD_DATA_PORT);
   }
   
   #if KBDIO_DEBUG >= 2
   static int call = 0;
   #endif
   
   /* read one byte from the keyboard */
   int
   read_kbd_data(KBDC p)
   {
   #if KBDIO_DEBUG >= 2
       if (++call > 2000) {
           call = 0;
           log(LOG_DEBUG, "kbdc: kbd q: %d calls, max %d chars, "
                                "aux q: %d calls, max %d chars\n",
                          kbdcp(p)->kbd.call_count, kbdcp(p)->kbd.max_qcount,
                          kbdcp(p)->aux.call_count, kbdcp(p)->aux.max_qcount);
       }
   #endif
   
       if (availq(&kbdcp(p)->kbd)) 
           return removeq(&kbdcp(p)->kbd);
       if (!wait_for_kbd_data(kbdcp(p)))
           return -1;              /* timeout */
       return inb(kbdcp(p)->port + KBD_DATA_PORT);
   }
   
   /* read one byte from the keyboard, but return immediately if 
    * no data is waiting
    */
   int
   read_kbd_data_no_wait(KBDC p)
   {
       int f;
   
   #if KBDIO_DEBUG >= 2
       if (++call > 2000) {
           call = 0;
           log(LOG_DEBUG, "kbdc: kbd q: %d calls, max %d chars, "
                                "aux q: %d calls, max %d chars\n",
                          kbdcp(p)->kbd.call_count, kbdcp(p)->kbd.max_qcount,
                          kbdcp(p)->aux.call_count, kbdcp(p)->aux.max_qcount);
       }
   #endif
   
       if (availq(&kbdcp(p)->kbd)) 
           return removeq(&kbdcp(p)->kbd);
       f = inb(kbdcp(p)->port + KBD_STATUS_PORT) & KBDS_BUFFER_FULL;
       if (f == KBDS_AUX_BUFFER_FULL) {
           DELAY(KBDD_DELAYTIME);
           addq(&kbdcp(p)->aux, inb(kbdcp(p)->port + KBD_DATA_PORT));
           f = inb(kbdcp(p)->port + KBD_STATUS_PORT) & KBDS_BUFFER_FULL;
       }
       if (f == KBDS_KBD_BUFFER_FULL) {
           DELAY(KBDD_DELAYTIME);
           return inb(kbdcp(p)->port + KBD_DATA_PORT);
       }
       return -1;          /* no data */
   }
   
   /* read one byte from the aux device */
   int
   read_aux_data(KBDC p)
   {
       if (availq(&kbdcp(p)->aux)) 
           return removeq(&kbdcp(p)->aux);
       if (!wait_for_aux_data(kbdcp(p)))
           return -1;              /* timeout */
       return inb(kbdcp(p)->port + KBD_DATA_PORT);
   }
   
   /* read one byte from the aux device, but return immediately if 
    * no data is waiting
    */
   int
   read_aux_data_no_wait(KBDC p)
   {
       int f;
   
       if (availq(&kbdcp(p)->aux)) 
           return removeq(&kbdcp(p)->aux);
       f = inb(kbdcp(p)->port + KBD_STATUS_PORT) & KBDS_BUFFER_FULL;
       if (f == KBDS_KBD_BUFFER_FULL) {
           DELAY(KBDD_DELAYTIME);
           addq(&kbdcp(p)->kbd, inb(kbdcp(p)->port + KBD_DATA_PORT));
           f = inb(kbdcp(p)->port + KBD_STATUS_PORT) & KBDS_BUFFER_FULL;
       }
       if (f == KBDS_AUX_BUFFER_FULL) {
           DELAY(KBDD_DELAYTIME);
           return inb(kbdcp(p)->port + KBD_DATA_PORT);
       }
       return -1;          /* no data */
   }
   
   /* discard data from the keyboard */
   void
   empty_kbd_buffer(KBDC p, int wait)
   {
       int t;
       int b;
       int f;
   #if KBDIO_DEBUG >= 2
       int c1 = 0;
       int c2 = 0;
   #endif
       int delta = 2;
   
       for (t = wait; t > 0; ) { 
           if ((f = inb(kbdcp(p)->port + KBD_STATUS_PORT)) & KBDS_ANY_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               b = inb(kbdcp(p)->port + KBD_DATA_PORT);
               if ((f & KBDS_BUFFER_FULL) == KBDS_AUX_BUFFER_FULL) {
                   addq(&kbdcp(p)->aux, b);
   #if KBDIO_DEBUG >= 2
                   ++c2;
               } else {
                   ++c1;
   #endif
               }
               t = wait;
           } else {
               t -= delta;
           }
           DELAY(delta*1000);
       }
   #if KBDIO_DEBUG >= 2
       if ((c1 > 0) || (c2 > 0))
           log(LOG_DEBUG, "kbdc: %d:%d char read (empty_kbd_buffer)\n", c1, c2);
   #endif
   
       emptyq(&kbdcp(p)->kbd);
   }
   
   /* discard data from the aux device */
   void
   empty_aux_buffer(KBDC p, int wait)
   {
       int t;
       int b;
       int f;
   #if KBDIO_DEBUG >= 2
       int c1 = 0;
       int c2 = 0;
   #endif
       int delta = 2;
   
       for (t = wait; t > 0; ) { 
           if ((f = inb(kbdcp(p)->port + KBD_STATUS_PORT)) & KBDS_ANY_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               b = inb(kbdcp(p)->port + KBD_DATA_PORT);
               if ((f & KBDS_BUFFER_FULL) == KBDS_KBD_BUFFER_FULL) {
                   addq(&kbdcp(p)->kbd, b);
   #if KBDIO_DEBUG >= 2
                   ++c1;
               } else {
                   ++c2;
   #endif
               }
               t = wait;
           } else {
               t -= delta;
           }
           DELAY(delta*1000);
       }
   #if KBDIO_DEBUG >= 2
       if ((c1 > 0) || (c2 > 0))
           log(LOG_DEBUG, "kbdc: %d:%d char read (empty_aux_buffer)\n", c1, c2);
   #endif
   
       emptyq(&kbdcp(p)->aux);
   }
   
   /* discard any data from the keyboard or the aux device */
   void
   empty_both_buffers(KBDC p, int wait)
   {
       int t;
       int f;
   #if KBDIO_DEBUG >= 2
       int c1 = 0;
       int c2 = 0;
   #endif
       int delta = 2;
   
       for (t = wait; t > 0; ) { 
           if ((f = inb(kbdcp(p)->port + KBD_STATUS_PORT)) & KBDS_ANY_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               (void)inb(kbdcp(p)->port + KBD_DATA_PORT);
   #if KBDIO_DEBUG >= 2
               if ((f & KBDS_BUFFER_FULL) == KBDS_KBD_BUFFER_FULL)
                   ++c1;
               else
                   ++c2;
   #endif
               t = wait;
           } else {
               t -= delta;
           }
           DELAY(delta*1000);
       }
   #if KBDIO_DEBUG >= 2
       if ((c1 > 0) || (c2 > 0))
           log(LOG_DEBUG, "kbdc: %d:%d char read (empty_both_buffers)\n", c1, c2);
   #endif
   
       emptyq(&kbdcp(p)->kbd);
       emptyq(&kbdcp(p)->aux);
   }
   
   /* keyboard and mouse device control */
   
   /* NOTE: enable the keyboard port but disable the keyboard 
    * interrupt before calling "reset_kbd()".
    */
   int
   reset_kbd(KBDC p)
   {
       int retry = KBD_MAXRETRY;
       int again = KBD_MAXWAIT;
       int c = KBD_RESEND;         /* keep the compiler happy */
   
       while (retry-- > 0) {
           empty_both_buffers(p, 10);
           if (!write_kbd_command(p, KBDC_RESET_KBD))
               continue;
           emptyq(&kbdcp(p)->kbd);
           c = read_controller_data(p);
           if (verbose || bootverbose)
               log(LOG_DEBUG, "kbdc: RESET_KBD return code:%04x\n", c);
           if (c == KBD_ACK)       /* keyboard has agreed to reset itself... */
               break;
       }
       if (retry < 0)
           return FALSE;
   
       while (again-- > 0) {
           /* wait awhile, well, in fact we must wait quite loooooooooooong */
           DELAY(KBD_RESETDELAY*1000);
           c = read_controller_data(p);    /* RESET_DONE/RESET_FAIL */
           if (c != -1)    /* wait again if the controller is not ready */
               break;
       }
       if (verbose || bootverbose)
           log(LOG_DEBUG, "kbdc: RESET_KBD status:%04x\n", c);
       if (c != KBD_RESET_DONE)
           return FALSE;
       return TRUE;
   }
   
   /* NOTE: enable the aux port but disable the aux interrupt
    * before calling `reset_aux_dev()'.
    */
   int
   reset_aux_dev(KBDC p)
   {
       int retry = KBD_MAXRETRY;
       int again = KBD_MAXWAIT;
       int c = PSM_RESEND;         /* keep the compiler happy */
   
       while (retry-- > 0) {
           empty_both_buffers(p, 10);
           if (!write_aux_command(p, PSMC_RESET_DEV))
               continue;
           emptyq(&kbdcp(p)->aux);
           /* NOTE: Compaq Armada laptops require extra delay here. XXX */
           for (again = KBD_MAXWAIT; again > 0; --again) {
               DELAY(KBD_RESETDELAY*1000);
               c = read_aux_data_no_wait(p);
               if (c != -1)
                   break;
           }
           if (verbose || bootverbose)
               log(LOG_DEBUG, "kbdc: RESET_AUX return code:%04x\n", c);
           if (c == PSM_ACK)       /* aux dev is about to reset... */
               break;
       }
       if (retry < 0)
           return FALSE;
   
       for (again = KBD_MAXWAIT; again > 0; --again) {
           /* wait awhile, well, quite looooooooooooong */
           DELAY(KBD_RESETDELAY*1000);
           c = read_aux_data_no_wait(p);   /* RESET_DONE/RESET_FAIL */
           if (c != -1)    /* wait again if the controller is not ready */
               break;
       }
       if (verbose || bootverbose)
           log(LOG_DEBUG, "kbdc: RESET_AUX status:%04x\n", c);
       if (c != PSM_RESET_DONE)    /* reset status */
           return FALSE;
   
       c = read_aux_data(p);       /* device ID */
       if (verbose || bootverbose)
           log(LOG_DEBUG, "kbdc: RESET_AUX ID:%04x\n", c);
       /* NOTE: we could check the device ID now, but leave it later... */
       return TRUE;
   }
   
   /* controller diagnostics and setup */
   
   int
   test_controller(KBDC p)
   {
       int retry = KBD_MAXRETRY;
       int again = KBD_MAXWAIT;
       int c = KBD_DIAG_FAIL;
   
       while (retry-- > 0) {
           empty_both_buffers(p, 10);
           if (write_controller_command(p, KBDC_DIAGNOSE))
               break;
       }
       if (retry < 0)
           return FALSE;
   
       emptyq(&kbdcp(p)->kbd);
       while (again-- > 0) {
           /* wait awhile */
           DELAY(KBD_RESETDELAY*1000);
           c = read_controller_data(p);    /* DIAG_DONE/DIAG_FAIL */
           if (c != -1)    /* wait again if the controller is not ready */
               break;
       }
       if (verbose || bootverbose)
           log(LOG_DEBUG, "kbdc: DIAGNOSE status:%04x\n", c);
       return (c == KBD_DIAG_DONE);
   }
   
   int
   test_kbd_port(KBDC p)
   {
       int retry = KBD_MAXRETRY;
       int again = KBD_MAXWAIT;
       int c = -1;
   
       while (retry-- > 0) {
           empty_both_buffers(p, 10);
           if (write_controller_command(p, KBDC_TEST_KBD_PORT))
               break;
       }
       if (retry < 0)
           return FALSE;
   
       emptyq(&kbdcp(p)->kbd);
       while (again-- > 0) {
           c = read_controller_data(p);
           if (c != -1)    /* try again if the controller is not ready */
               break;
       }
       if (verbose || bootverbose)
           log(LOG_DEBUG, "kbdc: TEST_KBD_PORT status:%04x\n", c);
       return c;
   }
   
   int
   test_aux_port(KBDC p)
   {
       int retry = KBD_MAXRETRY;
       int again = KBD_MAXWAIT;
       int c = -1;
   
       while (retry-- > 0) {
           empty_both_buffers(p, 10);
           if (write_controller_command(p, KBDC_TEST_AUX_PORT))
               break;
       }
       if (retry < 0)
           return FALSE;
   
       emptyq(&kbdcp(p)->kbd);
       while (again-- > 0) {
           c = read_controller_data(p);
           if (c != -1)    /* try again if the controller is not ready */
               break;
       }
       if (verbose || bootverbose)
           log(LOG_DEBUG, "kbdc: TEST_AUX_PORT status:%04x\n", c);
       return c;
   }
   
   int
   kbdc_get_device_mask(KBDC p)
   {
       return kbdcp(p)->command_mask;
   }
   
   void
   kbdc_set_device_mask(KBDC p, int mask)
   {
       kbdcp(p)->command_mask = 
           mask & (KBD_KBD_CONTROL_BITS | KBD_AUX_CONTROL_BITS);
   }
   
   int
   get_controller_command_byte(KBDC p)
   {
       if (kbdcp(p)->command_byte != -1)
           return kbdcp(p)->command_byte;
       if (!write_controller_command(p, KBDC_GET_COMMAND_BYTE))
           return -1;
       emptyq(&kbdcp(p)->kbd);
       kbdcp(p)->command_byte = read_controller_data(p);
       return kbdcp(p)->command_byte;
   }
   
   int
   set_controller_command_byte(KBDC p, int mask, int command)
   {
       if (get_controller_command_byte(p) == -1)
           return FALSE;
  
      command = (kbdcp(p)->command_byte & ~mask) | (command & mask);
      if (command & KBD_DISABLE_KBD_PORT) {
          if (!write_controller_command(p, KBDC_DISABLE_KBD_PORT))
              return FALSE;
      }
      if (!write_controller_command(p, KBDC_SET_COMMAND_BYTE))
          return FALSE;
      if (!write_controller_data(p, command))
          return FALSE;
      kbdcp(p)->command_byte = command;
  
      if (verbose)
          log(LOG_DEBUG, "kbdc: new command byte:%04x (set_controller...)\n",
              command);
  
      return TRUE;
  }

Cache object: 0ffceedfa4cb30e16bc7f8545fea5c22