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

     /*-
      * SPDX-License-Identifier: BSD-3-Clause
      *
      * 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.
     *
     * from kbdio.c,v 1.13 1998/09/25 11:55:46 yokota Exp
     */
    
    #include <sys/cdefs.h>
    __FBSDID("$FreeBSD$");
    
    #include "opt_kbd.h"
    
    #include <sys/param.h>
    #include <sys/systm.h>
    #include <sys/bus.h>
    #include <sys/malloc.h>
    #include <sys/syslog.h>
    #include <machine/bus.h>
    #include <machine/resource.h>
    #include <sys/rman.h>
    
    #if defined(__amd64__)
    #include <machine/clock.h>
    #endif
    
    #include <dev/atkbdc/atkbdcreg.h>
    
    #include <isa/isareg.h>
    
    /* constants */
    
    #define MAXKBDC         1               /* XXX */
    
    /* macros */
    
    #ifndef MAX
    #define MAX(x, y)       ((x) > (y) ? (x) : (y))
    #endif
    
    #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
    
    #define read_data(k)    (bus_space_read_1((k)->iot, (k)->ioh0, 0))
    #define read_status(k)  (bus_space_read_1((k)->iot, (k)->ioh1, 0))
    #define write_data(k, d)        \
                            (bus_space_write_1((k)->iot, (k)->ioh0, 0, (d)))
    #define write_command(k, d)     \
                            (bus_space_write_1((k)->iot, (k)->ioh1, 0, (d)))
    
    /* 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, bus_space_tag_t tag,
                            bus_space_handle_t h0, bus_space_handle_t h1);
    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);
   
   struct atkbdc_quirks {
       const char* bios_vendor;
       const char* maker;
       const char* product;
       int         quirk;
   };
   
   static struct atkbdc_quirks quirks[] = {
       {"coreboot", "System76", NULL, 0},
       {"coreboot", NULL, NULL,
           KBDC_QUIRK_KEEP_ACTIVATED | KBDC_QUIRK_IGNORE_PROBE_RESULT |
           KBDC_QUIRK_RESET_AFTER_PROBE | KBDC_QUIRK_SETLEDS_ON_INIT},
       /* KBDC hangs on Lenovo X120e and X121e after disabling AUX MUX */
       {NULL, "LENOVO", NULL, KBDC_QUIRK_DISABLE_MUX_PROBE},
   };
   
   #define QUIRK_STR_MATCH(s1, s2) (s1 == NULL || \
       (s2 != NULL && !strcmp(s1, s2)))
   
   static int
   atkbdc_getquirks(void)
   {
       int i;
       char* bios_vendor = kern_getenv("smbios.bios.vendor");
       char* maker = kern_getenv("smbios.system.maker");
       char* product = kern_getenv("smbios.system.product");
   
       for (i = 0; i < nitems(quirks); i++)
           if (QUIRK_STR_MATCH(quirks[i].bios_vendor, bios_vendor) &&
               QUIRK_STR_MATCH(quirks[i].maker, maker) &&
               QUIRK_STR_MATCH(quirks[i].product, product))
                   return (quirks[i].quirk);
   
       return (0);
   }
   
   atkbdc_softc_t
   *atkbdc_get_softc(int unit)
   {
           atkbdc_softc_t *sc;
   
           if (unit >= nitems(atkbdc_softc))
                   return NULL;
           sc = atkbdc_softc[unit];
           if (sc == NULL) {
                   sc = atkbdc_softc[unit]
                      = malloc(sizeof(*sc), M_DEVBUF, M_NOWAIT | M_ZERO);
                   if (sc == NULL)
                           return NULL;
           }
           return sc;
   }
   
   int
   atkbdc_probe_unit(int unit, struct resource *port0, struct resource *port1)
   {
           if (rman_get_start(port0) <= 0)
                   return ENXIO;
           if (rman_get_start(port1) <= 0)
                   return ENXIO;
           return 0;
   }
   
   int
   atkbdc_attach_unit(int unit, atkbdc_softc_t *sc, struct resource *port0,
                      struct resource *port1)
   {
           return atkbdc_setup(sc, rman_get_bustag(port0),
                               rman_get_bushandle(port0),
                               rman_get_bushandle(port1));
   }
   
   /* the backdoor to the keyboard controller! XXX */
   int
   atkbdc_configure(void)
   {
           bus_space_tag_t tag;
           bus_space_handle_t h0;
           bus_space_handle_t h1;
   #if defined(__i386__) || defined(__amd64__)
           volatile int i;
           register_t flags;
   #endif
           int port0;
           int port1;
   
           /* XXX: tag should be passed from the caller */
   #if defined(__amd64__) || defined(__i386__)
           tag = X86_BUS_SPACE_IO;
   #else
   #error "define tag!"
   #endif
   
           port0 = IO_KBD;
           resource_int_value("atkbdc", 0, "port", &port0);
           port1 = IO_KBD + KBD_STATUS_PORT;
   #ifdef notyet
           bus_space_map(tag, port0, IO_KBDSIZE, 0, &h0);
           bus_space_map(tag, port1, IO_KBDSIZE, 0, &h1);
   #else
           h0 = (bus_space_handle_t)port0;
           h1 = (bus_space_handle_t)port1;
   #endif
   
   #if defined(__i386__) || defined(__amd64__)
           /*
            * Check if we really have AT keyboard controller. Poll status
            * register until we get "all clear" indication. If no such
            * indication comes, it probably means that there is no AT
            * keyboard controller present. Give up in such case. Check relies
            * on the fact that reading from non-existing in/out port returns
            * 0xff on i386. May or may not be true on other platforms.
            */
           flags = intr_disable();
           for (i = 0; i != 65535; i++) {
                   if ((bus_space_read_1(tag, h1, 0) & 0x2) == 0)
                           break;
           }
           intr_restore(flags);
           if (i == 65535)
                   return ENXIO;
   #endif
   
           return atkbdc_setup(atkbdc_softc[0], tag, h0, h1);
   }
   
   static int
   atkbdc_setup(atkbdc_softc_t *sc, bus_space_tag_t tag, bus_space_handle_t h0,
                bus_space_handle_t h1)
   {
   #if defined(__amd64__)
           u_int64_t tscval[3], read_delay;
           register_t flags;
   #endif
   
           if (sc->ioh0 == 0) {    /* XXX */
               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;
               sc->aux_mux_enabled = FALSE;
   #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->iot = tag;
           sc->ioh0 = h0;
           sc->ioh1 = h1;
   
   #if defined(__amd64__)
           /*
            * On certain chipsets AT keyboard controller isn't present and is
            * emulated by BIOS using SMI interrupt. On those chipsets reading
            * from the status port may be thousand times slower than usually.
            * Sometimes this emilation is not working properly resulting in
            * commands timing our and since we assume that inb() operation 
            * takes very little time to complete we need to adjust number of
            * retries to keep waiting time within a designed limits (100ms).
            * Measure time it takes to make read_status() call and adjust
            * number of retries accordingly.
            */
           flags = intr_disable();
           tscval[0] = rdtsc();
           read_status(sc);
           tscval[1] = rdtsc();
           DELAY(1000);
           tscval[2] = rdtsc();
           intr_restore(flags);
           read_delay = tscval[1] - tscval[0];
           read_delay /= (tscval[2] - tscval[1]) / 1000;
           sc->retry = 100000 / ((KBDD_DELAYTIME * 2) + read_delay);
   #else
           sc->retry = 5000;
   #endif
           sc->quirks = atkbdc_getquirks();
   
           return 0;
   }
   
   /* open a keyboard controller */
   KBDC 
   atkbdc_open(int unit)
   {
       if (unit <= 0)
           unit = 0;
       if (unit >= MAXKBDC)
           return NULL;
       if ((atkbdc_softc[unit]->port0 != NULL)
           || (atkbdc_softc[unit]->ioh0 != 0))             /* XXX */
           return atkbdc_softc[unit];
       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 drivers which utilize 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 poll 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
    *       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 any
    *       necessary I/O operation within one invocation of the routine.
    *       This means 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 = p->lock;
       p->lock = lock;
   
       return (prevlock != lock);
   }
   
   /* check if any data is waiting to be processed */
   int
   kbdc_data_ready(KBDC p)
   {
       return (availq(&p->kbd) || availq(&p->aux)
           || (read_status(p) & 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)
   {
       int retry;
       int f;
   
       /* CPU will stay inside the loop for 100msec at most */
       retry = kbdc->retry;
   
       while ((f = read_status(kbdc)) & KBDS_INPUT_BUFFER_FULL) {
           if ((f & KBDS_BUFFER_FULL) == KBDS_KBD_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               addq(&kbdc->kbd, read_data(kbdc));
           } else if ((f & KBDS_BUFFER_FULL) == KBDS_AUX_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               addq(&kbdc->aux, read_data(kbdc));
           }
           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)
   {
       int retry;
       int f;
   
       /* CPU will stay inside the loop for 200msec at most */
       retry = kbdc->retry * 2;
   
       while ((f = read_status(kbdc) & 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)
   {
       int retry;
       int f;
   
       /* CPU will stay inside the loop for 200msec at most */
       retry = kbdc->retry * 2;
   
       while ((f = read_status(kbdc) & KBDS_BUFFER_FULL)
               != KBDS_KBD_BUFFER_FULL) {
           if (f == KBDS_AUX_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               addq(&kbdc->aux, read_data(kbdc));
           }
           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)
   {
       int retry;
       int f;
       int b;
   
       /* CPU will stay inside the loop for 200msec at most */
       retry = kbdc->retry * 2;
   
       while (retry-- > 0) {
           if ((f = read_status(kbdc)) & KBDS_ANY_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               b = read_data(kbdc);
               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)
   {
       int retry;
       int f;
   
       /* CPU will stay inside the loop for 200msec at most */
       retry = kbdc->retry * 2;
   
       while ((f = read_status(kbdc) & KBDS_BUFFER_FULL)
               != KBDS_AUX_BUFFER_FULL) {
           if (f == KBDS_KBD_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               addq(&kbdc->kbd, read_data(kbdc));
           }
           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)
   {
       int retry;
       int f;
       int b;
   
       /* CPU will stay inside the loop for 200msec at most */
       retry = kbdc->retry * 2;
   
       while (retry-- > 0) {
           if ((f = read_status(kbdc)) & KBDS_ANY_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               b = read_data(kbdc);
               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(p))
           return FALSE;
       write_command(p, c);
       return TRUE;
   }
   
   /* write a one byte data to the controller */
   int
   write_controller_data(KBDC p, int c)
   {
       if (!wait_while_controller_busy(p))
           return FALSE;
       write_data(p, c);
       return TRUE;
   }
   
   /* write a one byte keyboard command */
   int
   write_kbd_command(KBDC p, int c)
   {
       if (!wait_while_controller_busy(p))
           return FALSE;
       write_data(p, c);
       return TRUE;
   }
   
   /* write a one byte auxiliary device command */
   int
   write_aux_command(KBDC p, int c)
   {
       int f;
   
       f = aux_mux_is_enabled(p) ?
           KBDC_WRITE_TO_AUX_MUX + p->aux_mux_port : KBDC_WRITE_TO_AUX;
   
       if (!write_controller_command(p, f))
           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(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(&p->aux);
           res = wait_for_aux_ack(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(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(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(&p->aux);
           res = wait_for_aux_ack(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(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(&p->kbd))
           return removeq(&p->kbd);
       if (availq(&p->aux))
           return removeq(&p->aux);
       if (!wait_for_data(p))
           return -1;              /* timeout */
       return read_data(p);
   }
   
   #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",
                          p->kbd.call_count, p->kbd.max_qcount,
                          p->aux.call_count, p->aux.max_qcount);
       }
   #endif
   
       if (availq(&p->kbd))
           return removeq(&p->kbd);
       if (!wait_for_kbd_data(p))
           return -1;              /* timeout */
       return read_data(p);
   }
   
   /* 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",
                          p->kbd.call_count, p->kbd.max_qcount,
                          p->aux.call_count, p->aux.max_qcount);
       }
   #endif
   
       if (availq(&p->kbd))
           return removeq(&p->kbd);
       f = read_status(p) & KBDS_BUFFER_FULL;
       if (f == KBDS_AUX_BUFFER_FULL) {
           DELAY(KBDD_DELAYTIME);
           addq(&p->aux, read_data(p));
           f = read_status(p) & KBDS_BUFFER_FULL;
       }
       if (f == KBDS_KBD_BUFFER_FULL) {
           DELAY(KBDD_DELAYTIME);
           return read_data(p);
       }
       return -1;          /* no data */
   }
   
   /* read one byte from the aux device */
   int
   read_aux_data(KBDC p)
   {
       if (availq(&p->aux))
           return removeq(&p->aux);
       if (!wait_for_aux_data(p))
           return -1;              /* timeout */
       return read_data(p);
   }
   
   /* 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(&p->aux))
           return removeq(&p->aux);
       f = read_status(p) & KBDS_BUFFER_FULL;
       if (f == KBDS_KBD_BUFFER_FULL) {
           DELAY(KBDD_DELAYTIME);
           addq(&p->kbd, read_data(p));
           f = read_status(p) & KBDS_BUFFER_FULL;
       }
       if (f == KBDS_AUX_BUFFER_FULL) {
           DELAY(KBDD_DELAYTIME);
           return read_data(p);
       }
       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 = read_status(p)) & KBDS_ANY_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               b = read_data(p);
               if ((f & KBDS_BUFFER_FULL) == KBDS_AUX_BUFFER_FULL) {
                   addq(&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(&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 = read_status(p)) & KBDS_ANY_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               b = read_data(p);
               if ((f & KBDS_BUFFER_FULL) == KBDS_KBD_BUFFER_FULL) {
                   addq(&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(&p->aux);
   }
   
   /* discard any data from the keyboard or the aux device */
   void
   empty_both_buffers(KBDC p, int wait)
   {
       int t;
       int f;
       int waited = 0;
   #if KBDIO_DEBUG >= 2
       int c1 = 0;
       int c2 = 0;
   #endif
       int delta = 2;
   
       for (t = wait; t > 0; ) { 
           if ((f = read_status(p)) & KBDS_ANY_BUFFER_FULL) {
               DELAY(KBDD_DELAYTIME);
               (void)read_data(p);
   #if KBDIO_DEBUG >= 2
               if ((f & KBDS_BUFFER_FULL) == KBDS_KBD_BUFFER_FULL)
                   ++c1;
               else
                   ++c2;
   #endif
               t = wait;
           } else {
               t -= delta;
           }
   
           /*
            * Some systems (Intel/IBM blades) do not have keyboard devices and
            * will thus hang in this procedure. Time out after delta seconds to
            * avoid this hang -- the keyboard attach will fail later on.
            */
           waited += (delta * 1000);
           if (waited == (delta * 1000000))
               return;
   
           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(&p->kbd);
       emptyq(&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(&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(&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(&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(&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(&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 p->command_mask;
  }
  
  void
  kbdc_set_device_mask(KBDC p, int mask)
  {
      p->command_mask =
          mask & (((p->quirks & KBDC_QUIRK_KEEP_ACTIVATED)
              ? 0 : KBD_KBD_CONTROL_BITS) | KBD_AUX_CONTROL_BITS);
  }
  
  int
  get_controller_command_byte(KBDC p)
  {
      if (p->command_byte != -1)
          return p->command_byte;
      if (!write_controller_command(p, KBDC_GET_COMMAND_BYTE))
          return -1;
      emptyq(&p->kbd);
      p->command_byte = read_controller_data(p);
      return p->command_byte;
  }
  
  int
  set_controller_command_byte(KBDC p, int mask, int command)
  {
      if (get_controller_command_byte(p) == -1)
          return FALSE;
  
      command = (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;
      p->command_byte = command;
  
      if (verbose)
          log(LOG_DEBUG, "kbdc: new command byte:%04x (set_controller...)\n",
              command);
  
      return TRUE;
  }
  
  /*
   * Rudimentary support for active PS/2 AUX port multiplexing.
   * Only write commands can be routed to a selected AUX port.
   * Source port of data processed by read commands is totally ignored.
   */
  static int
  set_aux_mux_state(KBDC p, int enabled)
  {
          int command, version;
  
          if (write_controller_command(p, KBDC_FORCE_AUX_OUTPUT) == 0 ||
              write_controller_data(p, 0xF0) == 0 ||
              read_controller_data(p) != 0xF0)
                  return (-1);
  
          if (write_controller_command(p, KBDC_FORCE_AUX_OUTPUT) == 0 ||
              write_controller_data(p, 0x56) == 0 ||
              read_controller_data(p) != 0x56)
                  return (-1);
  
          command = enabled ? 0xa4 : 0xa5;
          if (write_controller_command(p, KBDC_FORCE_AUX_OUTPUT) == 0 ||
              write_controller_data(p, command) == 0 ||
              (version = read_controller_data(p)) == command)
                  return (-1);
  
          return (version);
  }
  
  int
  set_active_aux_mux_port(KBDC p, int port)
  {
  
          if (!aux_mux_is_enabled(p))
                  return (FALSE);
  
          if (port < 0 || port >= KBDC_AUX_MUX_NUM_PORTS)
                  return (FALSE);
  
          p->aux_mux_port = port;
  
          return (TRUE);
  }
  
  /* Checks for active multiplexing support and enables it */
  int
  enable_aux_mux(KBDC p)
  {
          int version;
  
          version = set_aux_mux_state(p, TRUE);
          if (version >= 0) {
                  p->aux_mux_enabled = TRUE;
                  set_active_aux_mux_port(p, 0);
          }
  
          return (version);
  }
  
  int
  disable_aux_mux(KBDC p)
  {
  
          p->aux_mux_enabled = FALSE;
  
          return (set_aux_mux_state(p, FALSE));
  }
  
  int
  aux_mux_is_enabled(KBDC p)
  {
  
          return (p->aux_mux_enabled);
  }

Cache object: 7e22b1f7f3f2b5b55cb60a136b187ce3