freebsd-dev/sys/dev/ppbus/vpoio.c
Nicolas Souchu adb50a3799 Cleanup and improve mode detection. Now, you should get what you actually
want according to the modes set with the ppc(4) flags. Especially, it
should fix some problems with mode detection of parallel chipsets
configured to EPP but which have timing troubles with the drives. In such
a case, the driver should now fall back to slower modes (PS2, NIBBLE).
2001-01-02 21:29:06 +00:00

773 lines
19 KiB
C

/*-
* Copyright (c) 1998, 1999 Nicolas Souchu
* Copyright (c) 2000 Alcove - 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.
*
* $FreeBSD$
*
*/
#ifdef _KERNEL
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/module.h>
#include <sys/bus.h>
#include <sys/malloc.h>
#endif
#ifdef _KERNEL
#endif
#include "opt_vpo.h"
#include <dev/ppbus/ppbio.h>
#include <dev/ppbus/ppbconf.h>
#include <dev/ppbus/ppb_msq.h>
#include <dev/ppbus/vpoio.h>
#include "ppbus_if.h"
/*
* The driver pools the drive. We may add a timeout queue to avoid
* active polling on nACK. I've tried this but it leads to unreliable
* transfers
*/
#define VP0_SELTMO 5000 /* select timeout */
#define VP0_FAST_SPINTMO 500000 /* wait status timeout */
#define VP0_LOW_SPINTMO 5000000 /* wait status timeout */
/*
* Actually, VP0 timings are more accurate (about few 16MHZ cycles),
* but succeeding in respecting such timings leads to architecture
* dependent considerations.
*/
#define VP0_PULSE 1
#define VP0_SECTOR_SIZE 512
#define VP0_BUFFER_SIZE 0x12000
#define n(flags) (~(flags) & (flags))
/*
* VP0 connections.
*/
#define H_AUTO n(AUTOFEED)
#define H_nAUTO AUTOFEED
#define H_STROBE n(STROBE)
#define H_nSTROBE STROBE
#define H_BSY n(nBUSY)
#define H_nBSY nBUSY
#define H_SEL SELECT
#define H_nSEL n(SELECT)
#define H_ERR PERROR
#define H_nERR n(PERROR)
#define H_ACK nACK
#define H_nACK n(nACK)
#define H_FLT nFAULT
#define H_nFLT n(nFAULT)
#define H_SELIN n(SELECTIN)
#define H_nSELIN SELECTIN
#define H_INIT nINIT
#define H_nINIT n(nINIT)
/*
* Microcode to execute very fast I/O sequences at the lowest bus level.
*/
/* call this macro to initialize connect/disconnect microsequences */
#define INIT_TRIG_MICROSEQ { \
int i; \
for (i=1; i <= 7; i+=2) { \
disconnect_microseq[i].arg[2] = (union ppb_insarg)d_pulse; \
connect_epp_microseq[i].arg[2] = \
connect_spp_microseq[i].arg[2] = (union ppb_insarg)c_pulse; \
} \
}
#define trig_d_pulse MS_TRIG(MS_REG_CTR,5,MS_UNKNOWN /* d_pulse */)
static char d_pulse[] = {
H_AUTO | H_nSELIN | H_INIT | H_STROBE, 0,
H_nAUTO | H_nSELIN | H_INIT | H_STROBE, VP0_PULSE,
H_AUTO | H_nSELIN | H_INIT | H_STROBE, 0,
H_AUTO | H_SELIN | H_INIT | H_STROBE, VP0_PULSE,
H_AUTO | H_nSELIN | H_INIT | H_STROBE, VP0_PULSE
};
#define trig_c_pulse MS_TRIG(MS_REG_CTR,5,MS_UNKNOWN /* c_pulse */)
static char c_pulse[] = {
H_AUTO | H_nSELIN | H_INIT | H_STROBE, 0,
H_AUTO | H_SELIN | H_INIT | H_STROBE, 0,
H_nAUTO | H_SELIN | H_INIT | H_STROBE, VP0_PULSE,
H_AUTO | H_SELIN | H_INIT | H_STROBE, 0,
H_AUTO | H_nSELIN | H_INIT | H_STROBE, VP0_PULSE
};
static struct ppb_microseq disconnect_microseq[] = {
MS_DASS(0x0), trig_d_pulse, MS_DASS(0x3c), trig_d_pulse,
MS_DASS(0x20), trig_d_pulse, MS_DASS(0xf), trig_d_pulse, MS_RET(0)
};
static struct ppb_microseq connect_epp_microseq[] = {
MS_DASS(0x0), trig_c_pulse, MS_DASS(0x3c), trig_c_pulse,
MS_DASS(0x20), trig_c_pulse, MS_DASS(0xcf), trig_c_pulse, MS_RET(0)
};
static struct ppb_microseq connect_spp_microseq[] = {
MS_DASS(0x0), trig_c_pulse, MS_DASS(0x3c), trig_c_pulse,
MS_DASS(0x20), trig_c_pulse, MS_DASS(0x8f), trig_c_pulse, MS_RET(0)
};
/*
* nibble_inbyte_hook()
*
* Formats high and low nibble into a character
*/
static int
nibble_inbyte_hook (void *p, char *ptr)
{
struct vpo_nibble *s = (struct vpo_nibble *)p;
/* increment the buffer pointer */
*ptr++ = ((s->l >> 4) & 0x0f) + (s->h & 0xf0);
return (0);
}
/*
* Macro used to initialize each vpoio_data structure during
* low level attachment
*
* XXX should be converted to ppb_MS_init_msq()
*/
#define INIT_NIBBLE_INBYTE_SUBMICROSEQ(vpo) { \
(vpo)->vpo_nibble_inbyte_msq[2].arg[2].p = \
(void *)&(vpo)->vpo_nibble.h; \
(vpo)->vpo_nibble_inbyte_msq[4].arg[2].p = \
(void *)&(vpo)->vpo_nibble.l; \
(vpo)->vpo_nibble_inbyte_msq[5].arg[0].f = \
nibble_inbyte_hook; \
(vpo)->vpo_nibble_inbyte_msq[5].arg[1].p = \
(void *)&(vpo)->vpo_nibble; \
}
/*
* This is the sub-microseqence for MS_GET in NIBBLE mode
* Retrieve the two nibbles and call the C function to generate the character
* and store it in the buffer (see nibble_inbyte_hook())
*/
static struct ppb_microseq nibble_inbyte_submicroseq[] = {
/* loop: */
MS_CASS( H_AUTO | H_SELIN | H_INIT | H_STROBE),
MS_DELAY(VP0_PULSE),
MS_RFETCH(MS_REG_STR, MS_FETCH_ALL, MS_UNKNOWN /* high nibble */),
MS_CASS(H_nAUTO | H_SELIN | H_INIT | H_STROBE),
MS_RFETCH(MS_REG_STR, MS_FETCH_ALL, MS_UNKNOWN /* low nibble */),
/* do a C call to format the received nibbles */
MS_C_CALL(MS_UNKNOWN /* C hook */, MS_UNKNOWN /* param */),
MS_DBRA(-7 /* loop */),
MS_CASS(H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_RET(0)
};
/*
* This is the sub-microseqence for MS_GET in PS2 mode
*/
static struct ppb_microseq ps2_inbyte_submicroseq[] = {
MS_CASS(PCD | H_AUTO | H_SELIN | H_INIT | H_nSTROBE),
/* loop: */
MS_RFETCH_P(1, MS_REG_DTR, MS_FETCH_ALL),
MS_CASS(PCD | H_nAUTO | H_SELIN | H_INIT | H_nSTROBE),
MS_CASS(PCD | H_AUTO | H_SELIN | H_INIT | H_nSTROBE),
MS_DBRA(-4 /* loop */),
MS_CASS(H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_RET(0)
};
/*
* This is the sub-microsequence for MS_PUT in both NIBBLE and PS2 modes
*/
static struct ppb_microseq spp_outbyte_submicroseq[] = {
/* loop: */
MS_RASSERT_P(1, MS_REG_DTR),
MS_CASS(H_nAUTO | H_nSELIN | H_INIT | H_STROBE),
MS_CASS( H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_DELAY(VP0_PULSE),
MS_DBRA(-5 /* loop */),
/* return from the put call */
MS_RET(0)
};
/* EPP 1.7 microsequences, ptr and len set at runtime */
static struct ppb_microseq epp17_outstr_body[] = {
MS_CASS(H_AUTO | H_SELIN | H_INIT | H_STROBE),
/* loop: */
MS_RASSERT_P(1, MS_REG_EPP_D),
MS_BRSET(TIMEOUT, 3 /* error */), /* EPP timeout? */
MS_DBRA(-3 /* loop */),
MS_CASS(H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_RET(0),
/* error: */
MS_CASS(H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_RET(1)
};
static struct ppb_microseq epp17_instr_body[] = {
MS_CASS(PCD | H_AUTO | H_SELIN | H_INIT | H_STROBE),
/* loop: */
MS_RFETCH_P(1, MS_REG_EPP_D, MS_FETCH_ALL),
MS_BRSET(TIMEOUT, 3 /* error */), /* EPP timeout? */
MS_DBRA(-3 /* loop */),
MS_CASS(PCD | H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_RET(0),
/* error: */
MS_CASS(PCD | H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_RET(1)
};
static struct ppb_microseq in_disk_mode[] = {
MS_CASS( H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_CASS(H_nAUTO | H_nSELIN | H_INIT | H_STROBE),
MS_BRCLEAR(H_FLT, 3 /* error */),
MS_CASS( H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_BRSET(H_FLT, 1 /* error */),
MS_RET(1),
/* error: */
MS_RET(0)
};
static int
vpoio_disconnect(struct vpoio_data *vpo)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
int ret;
ppb_MS_microseq(ppbus, vpo->vpo_dev, disconnect_microseq, &ret);
return (ppb_release_bus(ppbus, vpo->vpo_dev));
}
/*
* how : PPB_WAIT or PPB_DONTWAIT
*/
static int
vpoio_connect(struct vpoio_data *vpo, int how)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
int error;
int ret;
if ((error = ppb_request_bus(ppbus, vpo->vpo_dev, how))) {
#ifdef VP0_DEBUG
printf("%s: can't request bus!\n", __FUNCTION__);
#endif
return error;
}
if (PPB_IN_EPP_MODE(ppbus))
ppb_MS_microseq(ppbus, vpo->vpo_dev, connect_epp_microseq, &ret);
else
ppb_MS_microseq(ppbus, vpo->vpo_dev, connect_spp_microseq, &ret);
return (0);
}
/*
* vpoio_reset()
*
* SCSI reset signal, the drive must be in disk mode
*/
static void
vpoio_reset (struct vpoio_data *vpo)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
int ret;
struct ppb_microseq reset_microseq[] = {
#define INITIATOR MS_PARAM(0, 1, MS_TYP_INT)
MS_DASS(MS_UNKNOWN),
MS_CASS(H_AUTO | H_nSELIN | H_nINIT | H_STROBE),
MS_DELAY(25),
MS_CASS(H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_RET(0)
};
ppb_MS_init_msq(reset_microseq, 1, INITIATOR, 1 << VP0_INITIATOR);
ppb_MS_microseq(ppbus, vpo->vpo_dev, reset_microseq, &ret);
return;
}
/*
* vpoio_in_disk_mode()
*/
static int
vpoio_in_disk_mode(struct vpoio_data *vpo)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
int ret;
ppb_MS_microseq(ppbus, vpo->vpo_dev, in_disk_mode, &ret);
return (ret);
}
/*
* vpoio_detect()
*
* Detect and initialise the VP0 adapter.
*/
static int
vpoio_detect(struct vpoio_data *vpo)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
int error, ret;
/* allocate the bus, then apply microsequences */
if ((error = ppb_request_bus(ppbus, vpo->vpo_dev, PPB_DONTWAIT)))
return (error);
ppb_MS_microseq(ppbus, vpo->vpo_dev, disconnect_microseq, &ret);
/* Force disconnection */
/* Try to enter EPP mode, then connect to the drive in EPP mode */
if (ppb_set_mode(ppbus, PPB_EPP) != -1) {
/* call manually the microseq instead of using the appropriate function
* since we already requested the ppbus */
ppb_MS_microseq(ppbus, vpo->vpo_dev, connect_epp_microseq, &ret);
}
/* If EPP mode switch failed or ZIP connection in EPP mode failed,
* try to connect in NIBBLE mode */
if (!vpoio_in_disk_mode(vpo)) {
/* The interface must be at least PS/2 or NIBBLE capable.
* There is no way to know if the ZIP will work with
* PS/2 mode since PS/2 and SPP both use the same connect
* sequence. One must supress PS/2 with boot flags if
* PS/2 mode fails (see ppc(4)).
*/
if (ppb_set_mode(ppbus, PPB_PS2) != -1) {
vpo->vpo_mode_found = VP0_MODE_PS2;
} else {
if (ppb_set_mode(ppbus, PPB_NIBBLE) == -1)
goto error;
vpo->vpo_mode_found = VP0_MODE_NIBBLE;
}
/* Can't know if the interface is capable of PS/2 yet */
ppb_MS_microseq(ppbus, vpo->vpo_dev, connect_spp_microseq, &ret);
if (!vpoio_in_disk_mode(vpo)) {
vpo->vpo_mode_found = VP0_MODE_UNDEFINED;
if (bootverbose)
printf("vpo%d: can't connect to the drive\n",
vpo->vpo_unit);
/* disconnect and release the bus */
ppb_MS_microseq(ppbus, vpo->vpo_dev, disconnect_microseq,
&ret);
goto error;
}
} else {
vpo->vpo_mode_found = VP0_MODE_EPP;
}
/* send SCSI reset signal */
vpoio_reset(vpo);
ppb_MS_microseq(ppbus, vpo->vpo_dev, disconnect_microseq, &ret);
/* ensure we are disconnected or daisy chained peripheral
* may cause serious problem to the disk */
if (vpoio_in_disk_mode(vpo)) {
if (bootverbose)
printf("vpo%d: can't disconnect from the drive\n",
vpo->vpo_unit);
goto error;
}
ppb_release_bus(ppbus, vpo->vpo_dev);
return (0);
error:
ppb_release_bus(ppbus, vpo->vpo_dev);
return (VP0_EINITFAILED);
}
/*
* vpoio_outstr()
*/
static int
vpoio_outstr(struct vpoio_data *vpo, char *buffer, int size)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
int error = 0;
ppb_MS_exec(ppbus, vpo->vpo_dev, MS_OP_PUT, (union ppb_insarg)buffer,
(union ppb_insarg)size, (union ppb_insarg)MS_UNKNOWN, &error);
ppb_ecp_sync(ppbus);
return (error);
}
/*
* vpoio_instr()
*/
static int
vpoio_instr(struct vpoio_data *vpo, char *buffer, int size)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
int error = 0;
ppb_MS_exec(ppbus, vpo->vpo_dev, MS_OP_GET, (union ppb_insarg)buffer,
(union ppb_insarg)size, (union ppb_insarg)MS_UNKNOWN, &error);
ppb_ecp_sync(ppbus);
return (error);
}
static char
vpoio_select(struct vpoio_data *vpo, int initiator, int target)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
int ret;
struct ppb_microseq select_microseq[] = {
/* parameter list
*/
#define SELECT_TARGET MS_PARAM(0, 1, MS_TYP_INT)
#define SELECT_INITIATOR MS_PARAM(3, 1, MS_TYP_INT)
/* send the select command to the drive */
MS_DASS(MS_UNKNOWN),
MS_CASS(H_nAUTO | H_nSELIN | H_INIT | H_STROBE),
MS_CASS( H_AUTO | H_nSELIN | H_INIT | H_STROBE),
MS_DASS(MS_UNKNOWN),
MS_CASS( H_AUTO | H_nSELIN | H_nINIT | H_STROBE),
/* now, wait until the drive is ready */
MS_SET(VP0_SELTMO),
/* loop: */ MS_BRSET(H_ACK, 2 /* ready */),
MS_DBRA(-2 /* loop */),
/* error: */ MS_RET(1),
/* ready: */ MS_RET(0)
};
/* initialize the select microsequence */
ppb_MS_init_msq(select_microseq, 2,
SELECT_TARGET, 1 << target,
SELECT_INITIATOR, 1 << initiator);
ppb_MS_microseq(ppbus, vpo->vpo_dev, select_microseq, &ret);
if (ret)
return (VP0_ESELECT_TIMEOUT);
return (0);
}
/*
* vpoio_wait()
*
* H_SELIN must be low.
*
* XXX should be ported to microseq
*/
static char
vpoio_wait(struct vpoio_data *vpo, int tmo)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
register int k;
register char r;
#if 0 /* broken */
if (ppb_poll_device(ppbus, 150, nBUSY, nBUSY, PPB_INTR))
return (0);
return (ppb_rstr(ppbus) & 0xf0);
#endif
/* XXX should be ported to microseq */
k = 0;
while (!((r = ppb_rstr(ppbus)) & nBUSY) && (k++ < tmo))
;
/*
* Return some status information.
* Semantics : 0xc0 = ZIP wants more data
* 0xd0 = ZIP wants to send more data
* 0xe0 = ZIP wants command
* 0xf0 = end of transfer, ZIP is sending status
*/
if (k < tmo)
return (r & 0xf0);
return (0); /* command timed out */
}
/*
* vpoio_probe()
*
* Low level probe of vpo device
*
*/
int
vpoio_probe(device_t dev, struct vpoio_data *vpo)
{
int error;
/* ppbus dependent initialisation */
vpo->vpo_dev = dev;
/*
* Initialize microsequence code
*/
INIT_TRIG_MICROSEQ;
/* now, try to initialise the drive */
if ((error = vpoio_detect(vpo))) {
return (error);
}
return (0);
}
/*
* vpoio_attach()
*
* Low level attachment of vpo device
*
*/
int
vpoio_attach(struct vpoio_data *vpo)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
int error = 0;
vpo->vpo_nibble_inbyte_msq = (struct ppb_microseq *)malloc(
sizeof(nibble_inbyte_submicroseq), M_DEVBUF, M_NOWAIT);
if (!vpo->vpo_nibble_inbyte_msq)
return (ENXIO);
bcopy((void *)nibble_inbyte_submicroseq,
(void *)vpo->vpo_nibble_inbyte_msq,
sizeof(nibble_inbyte_submicroseq));
INIT_NIBBLE_INBYTE_SUBMICROSEQ(vpo);
/*
* Initialize mode dependent in/out microsequences
*/
if ((error = ppb_request_bus(ppbus, vpo->vpo_dev, PPB_WAIT)))
goto error;
/* ppbus sets automatically the last mode entered during detection */
switch (vpo->vpo_mode_found) {
case VP0_MODE_EPP:
ppb_MS_GET_init(ppbus, vpo->vpo_dev, epp17_instr_body);
ppb_MS_PUT_init(ppbus, vpo->vpo_dev, epp17_outstr_body);
printf("vpo%d: EPP mode\n", vpo->vpo_unit);
break;
case VP0_MODE_PS2:
ppb_MS_GET_init(ppbus, vpo->vpo_dev, ps2_inbyte_submicroseq);
ppb_MS_PUT_init(ppbus, vpo->vpo_dev, spp_outbyte_submicroseq);
printf("vpo%d: PS2 mode\n", vpo->vpo_unit);
break;
case VP0_MODE_NIBBLE:
ppb_MS_GET_init(ppbus, vpo->vpo_dev, vpo->vpo_nibble_inbyte_msq);
ppb_MS_PUT_init(ppbus, vpo->vpo_dev, spp_outbyte_submicroseq);
printf("vpo%d: NIBBLE mode\n", vpo->vpo_unit);
break;
default:
panic("vpo: unknown mode %d", vpo->vpo_mode_found);
}
ppb_release_bus(ppbus, vpo->vpo_dev);
error:
return (error);
}
/*
* vpoio_reset_bus()
*
*/
int
vpoio_reset_bus(struct vpoio_data *vpo)
{
/* first, connect to the drive */
if (vpoio_connect(vpo, PPB_WAIT|PPB_INTR) || !vpoio_in_disk_mode(vpo)) {
#ifdef VP0_DEBUG
printf("%s: not in disk mode!\n", __FUNCTION__);
#endif
/* release ppbus */
vpoio_disconnect(vpo);
return (1);
}
/* reset the SCSI bus */
vpoio_reset(vpo);
/* then disconnect */
vpoio_disconnect(vpo);
return (0);
}
/*
* vpoio_do_scsi()
*
* Send an SCSI command
*
*/
int
vpoio_do_scsi(struct vpoio_data *vpo, int host, int target, char *command,
int clen, char *buffer, int blen, int *result, int *count,
int *ret)
{
device_t ppbus = device_get_parent(vpo->vpo_dev);
register char r;
char l, h = 0;
int len, error = 0;
register int k;
/*
* enter disk state, allocate the ppbus
*
* XXX
* Should we allow this call to be interruptible?
* The only way to report the interruption is to return
* EIO do upper SCSI code :^(
*/
if ((error = vpoio_connect(vpo, PPB_WAIT|PPB_INTR)))
return (error);
if (!vpoio_in_disk_mode(vpo)) {
*ret = VP0_ECONNECT; goto error;
}
if ((*ret = vpoio_select(vpo,host,target)))
goto error;
/*
* Send the command ...
*
* set H_SELIN low for vpoio_wait().
*/
ppb_wctr(ppbus, H_AUTO | H_nSELIN | H_INIT | H_STROBE);
for (k = 0; k < clen; k++) {
if (vpoio_wait(vpo, VP0_FAST_SPINTMO) != (char)0xe0) {
*ret = VP0_ECMD_TIMEOUT;
goto error;
}
if (vpoio_outstr(vpo, &command[k], 1)) {
*ret = VP0_EPPDATA_TIMEOUT;
goto error;
}
}
/*
* Completion ...
*/
*count = 0;
for (;;) {
if (!(r = vpoio_wait(vpo, VP0_LOW_SPINTMO))) {
*ret = VP0_ESTATUS_TIMEOUT; goto error;
}
/* stop when the ZIP wants to send status */
if (r == (char)0xf0)
break;
if (*count >= blen) {
*ret = VP0_EDATA_OVERFLOW;
goto error;
}
/* if in EPP mode or writing bytes, try to transfer a sector
* otherwise, just send one byte
*/
if (PPB_IN_EPP_MODE(ppbus) || r == (char)0xc0)
len = (((blen - *count) >= VP0_SECTOR_SIZE)) ?
VP0_SECTOR_SIZE : 1;
else
len = 1;
/* ZIP wants to send data? */
if (r == (char)0xc0)
error = vpoio_outstr(vpo, &buffer[*count], len);
else
error = vpoio_instr(vpo, &buffer[*count], len);
if (error) {
*ret = error;
goto error;
}
*count += len;
}
if (vpoio_instr(vpo, &l, 1)) {
*ret = VP0_EOTHER; goto error;
}
/* check if the ZIP wants to send more status */
if (vpoio_wait(vpo, VP0_FAST_SPINTMO) == (char)0xf0)
if (vpoio_instr(vpo, &h, 1)) {
*ret = VP0_EOTHER+2; goto error;
}
*result = ((int) h << 8) | ((int) l & 0xff);
error:
/* return to printer state, release the ppbus */
vpoio_disconnect(vpo);
return (0);
}