FreeBSD/Linux Kernel Cross Reference
sys/dev/ppbus/ppb_1284.c

     /*-
      * Copyright (c) 1997 Nicolas Souchu
      * 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.
     *
     * 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.
     *
     *
     */
    
    #include <sys/cdefs.h>
    __FBSDID("$FreeBSD$");
    
    /*
     * General purpose routines for the IEEE1284-1994 Standard
     */
    
    #include "opt_ppb_1284.h"
    
    #include <sys/param.h>
    #include <sys/lock.h>
    #include <sys/mutex.h>
    #include <sys/systm.h>
    #include <sys/bus.h>
    
    
    #include <dev/ppbus/ppbconf.h>
    #include <dev/ppbus/ppb_1284.h>
    
    #include "ppbus_if.h"
    
    #include <dev/ppbus/ppbio.h>
    
    #define DEVTOSOFTC(dev) ((struct ppb_data *)device_get_softc(dev))
    
    /*
     * do_1284_wait()
     *
     * Wait for the peripherial up to 40ms
     */
    static int
    do_1284_wait(device_t bus, char mask, char status)
    {
            return (ppb_poll_bus(bus, 4, mask, status, PPB_NOINTR | PPB_POLL));
    }
    
    static int
    do_peripheral_wait(device_t bus, char mask, char status)
    {
            return (ppb_poll_bus(bus, 100, mask, status, PPB_NOINTR | PPB_POLL));
    }
    
    #define nibble2char(s) (((s & ~nACK) >> 3) | (~s & nBUSY) >> 4)
    
    /*
     * ppb_1284_reset_error()
     *
     * Unconditionaly reset the error field
     */
    static int
    ppb_1284_reset_error(device_t bus, int state)
    {
            struct ppb_data *ppb = DEVTOSOFTC(bus);
    
            ppb->error = PPB_NO_ERROR;
            ppb->state = state;
    
            return (0);
    }
    
    /*
     * ppb_1284_get_state()
     *
     * Get IEEE1284 state
     */
    int
    ppb_1284_get_state(device_t bus)
    {
            struct ppb_data *ppb = DEVTOSOFTC(bus);
    
            mtx_assert(ppb->ppc_lock, MA_OWNED);
           return (ppb->state);
   }
   
   /*
    * ppb_1284_set_state()
    *
    * Change IEEE1284 state if no error occured
    */
   int
   ppb_1284_set_state(device_t bus, int state)
   {
           struct ppb_data *ppb = DEVTOSOFTC(bus);
   
           /* call ppb_1284_reset_error() if you absolutly want to change
            * the state from PPB_ERROR to another */
           mtx_assert(ppb->ppc_lock, MA_OWNED);
           if ((ppb->state != PPB_ERROR) &&
                           (ppb->error == PPB_NO_ERROR)) {
                   ppb->state = state;
                   ppb->error = PPB_NO_ERROR;
           }
   
           return (0);
   }
   
   static int
   ppb_1284_set_error(device_t bus, int error, int event)
   {
           struct ppb_data *ppb = DEVTOSOFTC(bus);
   
           /* do not accumulate errors */
           if ((ppb->error == PPB_NO_ERROR) &&
                           (ppb->state != PPB_ERROR)) {
                   ppb->error = error;
                   ppb->state = PPB_ERROR;
           }
   
   #ifdef DEBUG_1284
           printf("ppb1284: error=%d status=0x%x event=%d\n", error,
                   ppb_rstr(bus) & 0xff, event);
   #endif
   
           return (0);
   }
   
   /*
    * ppb_request_mode()
    *
    * Converts mode+options into ext. value
    */
   static int
   ppb_request_mode(int mode, int options)
   {
           int request_mode = 0;
   
           if (options & PPB_EXTENSIBILITY_LINK) {
                   request_mode = EXT_LINK_1284_NORMAL;
   
           } else {
                   switch (mode) {
                   case PPB_NIBBLE:
                           request_mode = (options & PPB_REQUEST_ID) ?
                                           NIBBLE_1284_REQUEST_ID :
                                           NIBBLE_1284_NORMAL;
                           break;
                   case PPB_PS2:
                           request_mode = (options & PPB_REQUEST_ID) ?
                                           BYTE_1284_REQUEST_ID :
                                           BYTE_1284_NORMAL;
                           break;
                   case PPB_ECP:
                           if (options & PPB_USE_RLE)
                                   request_mode = (options & PPB_REQUEST_ID) ?
                                           ECP_1284_RLE_REQUEST_ID :
                                           ECP_1284_RLE;
                           else
                                   request_mode = (options & PPB_REQUEST_ID) ?
                                           ECP_1284_REQUEST_ID :
                                           ECP_1284_NORMAL;
                           break;
                   case PPB_EPP:
                           request_mode = EPP_1284_NORMAL;
                           break;
                   default:
                           panic("%s: unsupported mode %d\n", __func__, mode);
                   }
           }
   
           return (request_mode);
   }
   
   /*
    * ppb_peripheral_negociate()
    *
    * Negociate the peripheral side
    */
   int
   ppb_peripheral_negociate(device_t bus, int mode, int options)
   {
           int spin, request_mode, error = 0;
           char r;
   
           ppb_set_mode(bus, PPB_COMPATIBLE);
           ppb_1284_set_state(bus, PPB_PERIPHERAL_NEGOCIATION);
   
           /* compute ext. value */
           request_mode = ppb_request_mode(mode, options);
   
           /* wait host */
           spin = 10;
           while (spin-- && (ppb_rstr(bus) & nBUSY))
                   DELAY(1);
   
           /* check termination */
           if (!(ppb_rstr(bus) & SELECT) || !spin) {
                   error = ENODEV;
                   goto error;
           }
   
           /* Event 4 - read ext. value */
           r = ppb_rdtr(bus);
   
           /* nibble mode is not supported */
           if ((r == (char)request_mode) ||
                           (r == NIBBLE_1284_NORMAL)) {
   
                   /* Event 5 - restore direction bit, no data avail */
                   ppb_wctr(bus, (STROBE | nINIT) & ~(SELECTIN));
                   DELAY(1);
   
                   /* Event 6 */
                   ppb_wctr(bus, (nINIT) & ~(SELECTIN | STROBE));
   
                   if (r == NIBBLE_1284_NORMAL) {
   #ifdef DEBUG_1284
                           printf("R");
   #endif
                           ppb_1284_set_error(bus, PPB_MODE_UNSUPPORTED, 4);
                           error = EINVAL;
                           goto error;
                   } else {
                           ppb_1284_set_state(bus, PPB_PERIPHERAL_IDLE);
                           switch (r) {
                           case BYTE_1284_NORMAL:
                                   ppb_set_mode(bus, PPB_BYTE);
                                   break;
                           default:
                                   break;
                           }
   #ifdef DEBUG_1284
                           printf("A");
   #endif
                           /* negociation succeeds */
                   }
           } else {
                   /* Event 5 - mode not supported */
                   ppb_wctr(bus, SELECTIN);
                   DELAY(1);
   
                   /* Event 6 */
                   ppb_wctr(bus, (SELECTIN) & ~(STROBE | nINIT));
                   ppb_1284_set_error(bus, PPB_MODE_UNSUPPORTED, 4);
   
   #ifdef DEBUG_1284
                   printf("r");
   #endif
                   error = EINVAL;
                   goto error;
           }
   
           return (0);
   
   error:
           ppb_peripheral_terminate(bus, PPB_WAIT);
           return (error);
   }
   
   /*
    * ppb_peripheral_terminate()
    *
    * Terminate peripheral transfer side
    *
    * Always return 0 in compatible mode
    */
   int
   ppb_peripheral_terminate(device_t bus, int how)
   {
           int error = 0;
   
   #ifdef DEBUG_1284
           printf("t");
   #endif
   
           ppb_1284_set_state(bus, PPB_PERIPHERAL_TERMINATION);
   
           /* Event 22 - wait up to host response time (1s) */
           if ((error = do_peripheral_wait(bus, SELECT | nBUSY, 0))) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 22);
                   goto error;
           }
   
           /* Event 24 */
           ppb_wctr(bus, (nINIT | STROBE) & ~(AUTOFEED | SELECTIN));
   
           /* Event 25 - wait up to host response time (1s) */
           if ((error = do_peripheral_wait(bus, nBUSY, nBUSY))) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 25);
                   goto error;
           }
   
           /* Event 26 */
           ppb_wctr(bus, (SELECTIN | nINIT | STROBE) & ~(AUTOFEED));
           DELAY(1);
           /* Event 27 */
           ppb_wctr(bus, (SELECTIN | nINIT) & ~(STROBE | AUTOFEED));
   
           /* Event 28 - wait up to host response time (1s) */
           if ((error = do_peripheral_wait(bus, nBUSY, 0))) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 28);
                   goto error;
           }
   
   error:
           ppb_set_mode(bus, PPB_COMPATIBLE);
           ppb_1284_set_state(bus, PPB_FORWARD_IDLE);
   
           return (0);
   }
   
   /*
    * byte_peripheral_outbyte()
    *
    * Write 1 byte in BYTE mode
    */
   static int
   byte_peripheral_outbyte(device_t bus, char *buffer, int last)
   {
           int error = 0;
   
           /* Event 7 */
           if ((error = do_1284_wait(bus, nBUSY, nBUSY))) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 7);
                   goto error;
           }
   
           /* check termination */
           if (!(ppb_rstr(bus) & SELECT)) {
                   ppb_peripheral_terminate(bus, PPB_WAIT);
                   goto error;
           }
   
           /* Event 15 - put byte on data lines */
   #ifdef DEBUG_1284
           printf("B");
   #endif
           ppb_wdtr(bus, *buffer);
   
           /* Event 9 */
           ppb_wctr(bus, (AUTOFEED | STROBE) & ~(nINIT | SELECTIN));
   
           /* Event 10 - wait data read */
           if ((error = do_peripheral_wait(bus, nBUSY, 0))) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 16);
                   goto error;
           }
   
           /* Event 11 */
           if (!last) {
                   ppb_wctr(bus, (AUTOFEED) & ~(nINIT | STROBE | SELECTIN));
           } else {
                   ppb_wctr(bus, (nINIT) & ~(STROBE | SELECTIN | AUTOFEED));
           }
   
   #if 0
           /* Event 16 - wait strobe */
           if ((error = do_peripheral_wait(bus, nACK | nBUSY, 0))) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 16);
                   goto error;
           }
   #endif
   
           /* check termination */
           if (!(ppb_rstr(bus) & SELECT)) {
                   ppb_peripheral_terminate(bus, PPB_WAIT);
                   goto error;
           }
   
   error:
           return (error);
   }
   
   /*
    * byte_peripheral_write()
    *
    * Write n bytes in BYTE mode
    */
   int
   byte_peripheral_write(device_t bus, char *buffer, int len, int *sent)
   {
           int error = 0, i;
           char r;
   
           ppb_1284_set_state(bus, PPB_PERIPHERAL_TRANSFER);
   
           /* wait forever, the remote host is master and should initiate
            * termination
            */
           for (i=0; i<len; i++) {
                   /* force remote nFAULT low to release the remote waiting
                    * process, if any
                    */
                   r = ppb_rctr(bus);
                   ppb_wctr(bus, r & ~nINIT);
   
   #ifdef DEBUG_1284
                   printf("y");
   #endif
                   /* Event 7 */
                   error = ppb_poll_bus(bus, PPB_FOREVER, nBUSY, nBUSY,
                                           PPB_INTR);
   
                   if (error && error != EWOULDBLOCK)
                           goto error;
   
   #ifdef DEBUG_1284
                   printf("b");
   #endif
                   if ((error = byte_peripheral_outbyte(bus, buffer+i, (i == len-1))))
                           goto error;
           }
   error:
           if (!error)
                   ppb_1284_set_state(bus, PPB_PERIPHERAL_IDLE);
   
           *sent = i;
           return (error);
   }
   
   /*
    * byte_1284_inbyte()
    *
    * Read 1 byte in BYTE mode
    */
   int
   byte_1284_inbyte(device_t bus, char *buffer)
   {
           int error = 0;
   
           /* Event 7 - ready to take data (nAUTO low) */
           ppb_wctr(bus, (PCD | nINIT | AUTOFEED) & ~(STROBE | SELECTIN));
   
           /* Event 9 - peripheral set nAck low */
           if ((error = do_1284_wait(bus, nACK, 0))) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 9);
                   goto error;
           }
   
           /* read the byte */
           *buffer = ppb_rdtr(bus);
   
           /* Event 10 - data received, can't accept more */
           ppb_wctr(bus, (nINIT) & ~(AUTOFEED | STROBE | SELECTIN));
   
           /* Event 11 - peripheral ack */
           if ((error = do_1284_wait(bus, nACK, nACK))) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 11);
                   goto error;
           }
   
           /* Event 16 - strobe */
           ppb_wctr(bus, (nINIT | STROBE) & ~(AUTOFEED | SELECTIN));
           DELAY(3);
           ppb_wctr(bus, (nINIT) & ~(AUTOFEED | STROBE | SELECTIN));
   
   error:
           return (error);
   }
   
   /*
    * nibble_1284_inbyte()
    *
    * Read 1 byte in NIBBLE mode
    */
   int
   nibble_1284_inbyte(device_t bus, char *buffer)
   {
           char nibble[2];
           int i, error;
   
           for (i = 0; i < 2; i++) {
   
                   /* Event 7 - ready to take data (nAUTO low) */
                   ppb_wctr(bus, (nINIT | AUTOFEED) & ~(STROBE | SELECTIN));
   
                   /* Event 8 - peripheral writes the first nibble */
   
                   /* Event 9 - peripheral set nAck low */
                   if ((error = do_1284_wait(bus, nACK, 0))) {
                           ppb_1284_set_error(bus, PPB_TIMEOUT, 9);
                           goto error;
                   }
   
                   /* read nibble */
                   nibble[i] = ppb_rstr(bus);
   
                   /* Event 10 - ack, nibble received */
                   ppb_wctr(bus, nINIT & ~(AUTOFEED | STROBE | SELECTIN));
   
                   /* Event 11 - wait ack from peripherial */
                   if ((error = do_1284_wait(bus, nACK, nACK))) {
                           ppb_1284_set_error(bus, PPB_TIMEOUT, 11);
                           goto error;
                   }
           }
   
           *buffer = ((nibble2char(nibble[1]) << 4) & 0xf0) |
                                   (nibble2char(nibble[0]) & 0x0f);
   
   error:
           return (error);
   }
   
   /*
    * spp_1284_read()
    *
    * Read in IEEE1284 NIBBLE/BYTE mode
    */
   int
   spp_1284_read(device_t bus, int mode, char *buffer, int max, int *read)
   {
           int error = 0, len = 0;
           int terminate_after_transfer = 1;
           int state;
   
           *read = len = 0;
   
           state = ppb_1284_get_state(bus);
   
           switch (state) {
           case PPB_FORWARD_IDLE:
                   if ((error = ppb_1284_negociate(bus, mode, 0)))
                           return (error);
                   break;
   
           case PPB_REVERSE_IDLE:
                   terminate_after_transfer = 0;
                   break;
   
           default:
                   ppb_1284_terminate(bus);
                   if ((error = ppb_1284_negociate(bus, mode, 0)))
                           return (error);
                   break;
           }
   
           while ((len < max) && !(ppb_rstr(bus) & (nFAULT))) {
   
                   ppb_1284_set_state(bus, PPB_REVERSE_TRANSFER);
   
   #ifdef DEBUG_1284
                   printf("B");
   #endif
   
                   switch (mode) {
                   case PPB_NIBBLE:
                           /* read a byte, error means no more data */
                           if (nibble_1284_inbyte(bus, buffer+len))
                                   goto end_while;
                           break;
                   case PPB_BYTE:
                           if (byte_1284_inbyte(bus, buffer+len))
                                   goto end_while;
                           break;
                   default:
                           error = EINVAL;
                           goto end_while;
                   }
                   len ++;
           }
   end_while:
   
           if (!error)
                   ppb_1284_set_state(bus, PPB_REVERSE_IDLE);
   
           *read = len;
   
           if (terminate_after_transfer || error)
                   ppb_1284_terminate(bus);
   
           return (error);
   }
   
   /*
    * ppb_1284_read_id()
    *
    */
   int
   ppb_1284_read_id(device_t bus, int mode, char *buffer,
                   int max, int *read)
   {
           int error = 0;
   
           /* fill the buffer with 0s */
           bzero(buffer, max);
   
           switch (mode) {
           case PPB_NIBBLE:
           case PPB_ECP:
                   if ((error = ppb_1284_negociate(bus, PPB_NIBBLE, PPB_REQUEST_ID)))
                           return (error);
                   error = spp_1284_read(bus, PPB_NIBBLE, buffer, max, read);
                   break;
           case PPB_BYTE:
                   if ((error = ppb_1284_negociate(bus, PPB_BYTE, PPB_REQUEST_ID)))
                           return (error);
                   error = spp_1284_read(bus, PPB_BYTE, buffer, max, read);
                   break;
           default:
                   panic("%s: unsupported mode %d\n", __func__, mode);
           }
   
           ppb_1284_terminate(bus);
           return (error);
   }
   
   /*
    * ppb_1284_read()
    *
    * IEEE1284 read
    */
   int
   ppb_1284_read(device_t bus, int mode, char *buffer,
                   int max, int *read)
   {
           int error = 0;
   
           switch (mode) {
           case PPB_NIBBLE:
           case PPB_BYTE:
                   error = spp_1284_read(bus, mode, buffer, max, read);
                   break;
           default:
                   return (EINVAL);
           }
   
           return (error);
   }
   
   /*
    * ppb_1284_negociate()
    *
    * IEEE1284 negociation phase
    *
    * Normal nibble mode or request device id mode (see ppb_1284.h)
    *
    * After negociation, nFAULT is low if data is available
    */
   int
   ppb_1284_negociate(device_t bus, int mode, int options)
   {
           int error;
           int request_mode;
   
   #ifdef DEBUG_1284
           printf("n");
   #endif
   
           if (ppb_1284_get_state(bus) >= PPB_PERIPHERAL_NEGOCIATION)
                   ppb_peripheral_terminate(bus, PPB_WAIT);
   
           if (ppb_1284_get_state(bus) != PPB_FORWARD_IDLE)
                   ppb_1284_terminate(bus);
   
   #ifdef DEBUG_1284
           printf("%d", mode);
   #endif
   
           /* ensure the host is in compatible mode */
           ppb_set_mode(bus, PPB_COMPATIBLE);
   
           /* reset error to catch the actual negociation error */
           ppb_1284_reset_error(bus, PPB_FORWARD_IDLE);
   
           /* calculate ext. value */
           request_mode = ppb_request_mode(mode, options);
   
           /* default state */
           ppb_wctr(bus, (nINIT | SELECTIN) & ~(STROBE | AUTOFEED));
           DELAY(1);
   
           /* enter negociation phase */
           ppb_1284_set_state(bus, PPB_NEGOCIATION);
   
           /* Event 0 - put the exten. value on the data lines */
           ppb_wdtr(bus, request_mode);
   
   #ifdef PERIPH_1284
           /* request remote host attention */
           ppb_wctr(bus, (nINIT | STROBE) & ~(AUTOFEED | SELECTIN));
           DELAY(1);
           ppb_wctr(bus, (nINIT) & ~(STROBE | AUTOFEED | SELECTIN));
   #else
           DELAY(1);
   
   #endif /* !PERIPH_1284 */
   
           /* Event 1 - enter IEEE1284 mode */
           ppb_wctr(bus, (nINIT | AUTOFEED) & ~(STROBE | SELECTIN));
   
   #ifdef PERIPH_1284
           /* ignore the PError line, wait a bit more, remote host's
            * interrupts don't respond fast enough */
           if (ppb_poll_bus(bus, 40, nACK | SELECT | nFAULT,
                                   SELECT | nFAULT, PPB_NOINTR | PPB_POLL)) {
                   ppb_1284_set_error(bus, PPB_NOT_IEEE1284, 2);
                   error = ENODEV;
                   goto error;
           }
   #else
           /* Event 2 - trying IEEE1284 dialog */
           if (do_1284_wait(bus, nACK | PERROR | SELECT | nFAULT,
                           PERROR  | SELECT | nFAULT)) {
                   ppb_1284_set_error(bus, PPB_NOT_IEEE1284, 2);
                   error = ENODEV;
                   goto error;
           }
   #endif /* !PERIPH_1284 */
   
           /* Event 3 - latch the ext. value to the peripheral */
           ppb_wctr(bus, (nINIT | STROBE | AUTOFEED) & ~SELECTIN);
           DELAY(1);
   
           /* Event 4 - IEEE1284 device recognized */
           ppb_wctr(bus, nINIT & ~(SELECTIN | AUTOFEED | STROBE));
   
           /* Event 6 - waiting for status lines */
           if (do_1284_wait(bus, nACK, nACK)) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 6);
                   error = EBUSY;
                   goto error;
           }
   
           /* Event 7 - quering result consider nACK not to misunderstand
            * a remote computer terminate sequence */
           if (options & PPB_EXTENSIBILITY_LINK) {
   
                   /* XXX not fully supported yet */
                   ppb_1284_terminate(bus);
                   return (0);
   
           }
           if (request_mode == NIBBLE_1284_NORMAL) {
                   if (do_1284_wait(bus, nACK | SELECT, nACK)) {
                           ppb_1284_set_error(bus, PPB_MODE_UNSUPPORTED, 7);
                           error = ENODEV;
                           goto error;
                   }
           } else {
                   if (do_1284_wait(bus, nACK | SELECT, SELECT | nACK)) {
                           ppb_1284_set_error(bus, PPB_MODE_UNSUPPORTED, 7);
                           error = ENODEV;
                           goto error;
                   }
           }
   
           switch (mode) {
           case PPB_NIBBLE:
           case PPB_PS2:
                   /* enter reverse idle phase */
                   ppb_1284_set_state(bus, PPB_REVERSE_IDLE);
                   break;
           case PPB_ECP:
                   /* negociation ok, now setup the communication */
                   ppb_1284_set_state(bus, PPB_SETUP);
                   ppb_wctr(bus, (nINIT | AUTOFEED) & ~(SELECTIN | STROBE));
   
   #ifdef PERIPH_1284
                   /* ignore PError line */
                   if (do_1284_wait(bus, nACK | SELECT | nBUSY,
                                           nACK | SELECT | nBUSY)) {
                           ppb_1284_set_error(bus, PPB_TIMEOUT, 30);
                           error = ENODEV;
                           goto error;
                   }
   #else
                   if (do_1284_wait(bus, nACK | SELECT | PERROR | nBUSY,
                                           nACK | SELECT | PERROR | nBUSY)) {
                           ppb_1284_set_error(bus, PPB_TIMEOUT, 30);
                           error = ENODEV;
                           goto error;
                   }
   #endif /* !PERIPH_1284 */
   
                   /* ok, the host enters the ForwardIdle state */
                   ppb_1284_set_state(bus, PPB_ECP_FORWARD_IDLE);
                   break;
           case PPB_EPP:
                   ppb_1284_set_state(bus, PPB_EPP_IDLE);
                   break;
   
           default:
                   panic("%s: unknown mode (%d)!", __func__, mode);
           }
           ppb_set_mode(bus, mode);
   
           return (0);
   
   error:
           ppb_1284_terminate(bus);
   
           return (error);
   }
   
   /*
    * ppb_1284_terminate()
    *
    * IEEE1284 termination phase, return code should ignored since the host
    * is _always_ in compatible mode after ppb_1284_terminate()
    */
   int
   ppb_1284_terminate(device_t bus)
   {
   
   #ifdef DEBUG_1284
           printf("T");
   #endif
   
           /* do not reset error here to keep the error that
            * may occured before the ppb_1284_terminate() call */
           ppb_1284_set_state(bus, PPB_TERMINATION);
   
   #ifdef PERIPH_1284
           /* request remote host attention */
           ppb_wctr(bus, (nINIT | STROBE | SELECTIN) & ~(AUTOFEED));
           DELAY(1);
   #endif /* PERIPH_1284 */
   
           /* Event 22 - set nSelectin low and nAutoFeed high */
           ppb_wctr(bus, (nINIT | SELECTIN) & ~(STROBE | AUTOFEED));
   
           /* Event 24 - waiting for peripheral, Xflag ignored */
           if (do_1284_wait(bus, nACK | nBUSY | nFAULT, nFAULT)) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 24);
                   goto error;
           }
   
           /* Event 25 - set nAutoFd low */
           ppb_wctr(bus, (nINIT | SELECTIN | AUTOFEED) & ~STROBE);
   
           /* Event 26 - compatible mode status is set */
   
           /* Event 27 - peripheral set nAck high */
           if (do_1284_wait(bus, nACK, nACK)) {
                   ppb_1284_set_error(bus, PPB_TIMEOUT, 27);
           }
   
           /* Event 28 - end termination, return to idle phase */
           ppb_wctr(bus, (nINIT | SELECTIN) & ~(STROBE | AUTOFEED));
   
   error:
           /* return to compatible mode */
           ppb_set_mode(bus, PPB_COMPATIBLE);
           ppb_1284_set_state(bus, PPB_FORWARD_IDLE);
   
           return (0);
   }

Cache object: db289445e3319fba0346a1e501833dee