/
imm.c
1300 lines (1148 loc) · 29.4 KB
/
imm.c
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/* imm.c -- low level driver for the IOMEGA MatchMaker
* parallel port SCSI host adapter.
*
* (The IMM is the embedded controller in the ZIP Plus drive.)
*
* Current Maintainer: David Campbell (Perth, Western Australia)
* campbell@torque.net
*
* My unoffical company acronym list is 21 pages long:
* FLA: Four letter acronym with built in facility for
* future expansion to five letters.
*/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/parport.h>
#include <linux/workqueue.h>
#include <asm/io.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
/* The following #define is to avoid a clash with hosts.c */
#define IMM_PROBE_SPP 0x0001
#define IMM_PROBE_PS2 0x0002
#define IMM_PROBE_ECR 0x0010
#define IMM_PROBE_EPP17 0x0100
#define IMM_PROBE_EPP19 0x0200
typedef struct {
struct pardevice *dev; /* Parport device entry */
int base; /* Actual port address */
int base_hi; /* Hi Base address for ECP-ISA chipset */
int mode; /* Transfer mode */
struct scsi_cmnd *cur_cmd; /* Current queued command */
struct work_struct imm_tq; /* Polling interrupt stuff */
unsigned long jstart; /* Jiffies at start */
unsigned failed:1; /* Failure flag */
unsigned dp:1; /* Data phase present */
unsigned rd:1; /* Read data in data phase */
unsigned wanted:1; /* Parport sharing busy flag */
wait_queue_head_t *waiting;
struct Scsi_Host *host;
struct list_head list;
} imm_struct;
static void imm_reset_pulse(unsigned int base);
static int device_check(imm_struct *dev);
#include "imm.h"
static inline imm_struct *imm_dev(struct Scsi_Host *host)
{
return *(imm_struct **)&host->hostdata;
}
static DEFINE_SPINLOCK(arbitration_lock);
static void got_it(imm_struct *dev)
{
dev->base = dev->dev->port->base;
if (dev->cur_cmd)
dev->cur_cmd->SCp.phase = 1;
else
wake_up(dev->waiting);
}
static void imm_wakeup(void *ref)
{
imm_struct *dev = (imm_struct *) ref;
unsigned long flags;
spin_lock_irqsave(&arbitration_lock, flags);
if (dev->wanted) {
parport_claim(dev->dev);
got_it(dev);
dev->wanted = 0;
}
spin_unlock_irqrestore(&arbitration_lock, flags);
}
static int imm_pb_claim(imm_struct *dev)
{
unsigned long flags;
int res = 1;
spin_lock_irqsave(&arbitration_lock, flags);
if (parport_claim(dev->dev) == 0) {
got_it(dev);
res = 0;
}
dev->wanted = res;
spin_unlock_irqrestore(&arbitration_lock, flags);
return res;
}
static void imm_pb_dismiss(imm_struct *dev)
{
unsigned long flags;
int wanted;
spin_lock_irqsave(&arbitration_lock, flags);
wanted = dev->wanted;
dev->wanted = 0;
spin_unlock_irqrestore(&arbitration_lock, flags);
if (!wanted)
parport_release(dev->dev);
}
static inline void imm_pb_release(imm_struct *dev)
{
parport_release(dev->dev);
}
/* This is to give the imm driver a way to modify the timings (and other
* parameters) by writing to the /proc/scsi/imm/0 file.
* Very simple method really... (Too simple, no error checking :( )
* Reason: Kernel hackers HATE having to unload and reload modules for
* testing...
* Also gives a method to use a script to obtain optimum timings (TODO)
*/
static inline int imm_proc_write(imm_struct *dev, char *buffer, int length)
{
unsigned long x;
if ((length > 5) && (strncmp(buffer, "mode=", 5) == 0)) {
x = simple_strtoul(buffer + 5, NULL, 0);
dev->mode = x;
return length;
}
printk("imm /proc: invalid variable\n");
return (-EINVAL);
}
static int imm_proc_info(struct Scsi_Host *host, char *buffer, char **start,
off_t offset, int length, int inout)
{
imm_struct *dev = imm_dev(host);
int len = 0;
if (inout)
return imm_proc_write(dev, buffer, length);
len += sprintf(buffer + len, "Version : %s\n", IMM_VERSION);
len +=
sprintf(buffer + len, "Parport : %s\n",
dev->dev->port->name);
len +=
sprintf(buffer + len, "Mode : %s\n",
IMM_MODE_STRING[dev->mode]);
/* Request for beyond end of buffer */
if (offset > len)
return 0;
*start = buffer + offset;
len -= offset;
if (len > length)
len = length;
return len;
}
#if IMM_DEBUG > 0
#define imm_fail(x,y) printk("imm: imm_fail(%i) from %s at line %d\n",\
y, __FUNCTION__, __LINE__); imm_fail_func(x,y);
static inline void
imm_fail_func(imm_struct *dev, int error_code)
#else
static inline void
imm_fail(imm_struct *dev, int error_code)
#endif
{
/* If we fail a device then we trash status / message bytes */
if (dev->cur_cmd) {
dev->cur_cmd->result = error_code << 16;
dev->failed = 1;
}
}
/*
* Wait for the high bit to be set.
*
* In principle, this could be tied to an interrupt, but the adapter
* doesn't appear to be designed to support interrupts. We spin on
* the 0x80 ready bit.
*/
static unsigned char imm_wait(imm_struct *dev)
{
int k;
unsigned short ppb = dev->base;
unsigned char r;
w_ctr(ppb, 0x0c);
k = IMM_SPIN_TMO;
do {
r = r_str(ppb);
k--;
udelay(1);
}
while (!(r & 0x80) && (k));
/*
* STR register (LPT base+1) to SCSI mapping:
*
* STR imm imm
* ===================================
* 0x80 S_REQ S_REQ
* 0x40 !S_BSY (????)
* 0x20 !S_CD !S_CD
* 0x10 !S_IO !S_IO
* 0x08 (????) !S_BSY
*
* imm imm meaning
* ==================================
* 0xf0 0xb8 Bit mask
* 0xc0 0x88 ZIP wants more data
* 0xd0 0x98 ZIP wants to send more data
* 0xe0 0xa8 ZIP is expecting SCSI command data
* 0xf0 0xb8 end of transfer, ZIP is sending status
*/
w_ctr(ppb, 0x04);
if (k)
return (r & 0xb8);
/* Counter expired - Time out occurred */
imm_fail(dev, DID_TIME_OUT);
printk("imm timeout in imm_wait\n");
return 0; /* command timed out */
}
static int imm_negotiate(imm_struct * tmp)
{
/*
* The following is supposedly the IEEE 1284-1994 negotiate
* sequence. I have yet to obtain a copy of the above standard
* so this is a bit of a guess...
*
* A fair chunk of this is based on the Linux parport implementation
* of IEEE 1284.
*
* Return 0 if data available
* 1 if no data available
*/
unsigned short base = tmp->base;
unsigned char a, mode;
switch (tmp->mode) {
case IMM_NIBBLE:
mode = 0x00;
break;
case IMM_PS2:
mode = 0x01;
break;
default:
return 0;
}
w_ctr(base, 0x04);
udelay(5);
w_dtr(base, mode);
udelay(100);
w_ctr(base, 0x06);
udelay(5);
a = (r_str(base) & 0x20) ? 0 : 1;
udelay(5);
w_ctr(base, 0x07);
udelay(5);
w_ctr(base, 0x06);
if (a) {
printk
("IMM: IEEE1284 negotiate indicates no data available.\n");
imm_fail(tmp, DID_ERROR);
}
return a;
}
/*
* Clear EPP timeout bit.
*/
static inline void epp_reset(unsigned short ppb)
{
int i;
i = r_str(ppb);
w_str(ppb, i);
w_str(ppb, i & 0xfe);
}
/*
* Wait for empty ECP fifo (if we are in ECP fifo mode only)
*/
static inline void ecp_sync(imm_struct *dev)
{
int i, ppb_hi = dev->base_hi;
if (ppb_hi == 0)
return;
if ((r_ecr(ppb_hi) & 0xe0) == 0x60) { /* mode 011 == ECP fifo mode */
for (i = 0; i < 100; i++) {
if (r_ecr(ppb_hi) & 0x01)
return;
udelay(5);
}
printk("imm: ECP sync failed as data still present in FIFO.\n");
}
}
static int imm_byte_out(unsigned short base, const char *buffer, int len)
{
int i;
w_ctr(base, 0x4); /* apparently a sane mode */
for (i = len >> 1; i; i--) {
w_dtr(base, *buffer++);
w_ctr(base, 0x5); /* Drop STROBE low */
w_dtr(base, *buffer++);
w_ctr(base, 0x0); /* STROBE high + INIT low */
}
w_ctr(base, 0x4); /* apparently a sane mode */
return 1; /* All went well - we hope! */
}
static int imm_nibble_in(unsigned short base, char *buffer, int len)
{
unsigned char l;
int i;
/*
* The following is based on documented timing signals
*/
w_ctr(base, 0x4);
for (i = len; i; i--) {
w_ctr(base, 0x6);
l = (r_str(base) & 0xf0) >> 4;
w_ctr(base, 0x5);
*buffer++ = (r_str(base) & 0xf0) | l;
w_ctr(base, 0x4);
}
return 1; /* All went well - we hope! */
}
static int imm_byte_in(unsigned short base, char *buffer, int len)
{
int i;
/*
* The following is based on documented timing signals
*/
w_ctr(base, 0x4);
for (i = len; i; i--) {
w_ctr(base, 0x26);
*buffer++ = r_dtr(base);
w_ctr(base, 0x25);
}
return 1; /* All went well - we hope! */
}
static int imm_out(imm_struct *dev, char *buffer, int len)
{
unsigned short ppb = dev->base;
int r = imm_wait(dev);
/*
* Make sure that:
* a) the SCSI bus is BUSY (device still listening)
* b) the device is listening
*/
if ((r & 0x18) != 0x08) {
imm_fail(dev, DID_ERROR);
printk("IMM: returned SCSI status %2x\n", r);
return 0;
}
switch (dev->mode) {
case IMM_EPP_32:
case IMM_EPP_16:
case IMM_EPP_8:
epp_reset(ppb);
w_ctr(ppb, 0x4);
#ifdef CONFIG_SCSI_IZIP_EPP16
if (!(((long) buffer | len) & 0x01))
outsw(ppb + 4, buffer, len >> 1);
#else
if (!(((long) buffer | len) & 0x03))
outsl(ppb + 4, buffer, len >> 2);
#endif
else
outsb(ppb + 4, buffer, len);
w_ctr(ppb, 0xc);
r = !(r_str(ppb) & 0x01);
w_ctr(ppb, 0xc);
ecp_sync(dev);
break;
case IMM_NIBBLE:
case IMM_PS2:
/* 8 bit output, with a loop */
r = imm_byte_out(ppb, buffer, len);
break;
default:
printk("IMM: bug in imm_out()\n");
r = 0;
}
return r;
}
static int imm_in(imm_struct *dev, char *buffer, int len)
{
unsigned short ppb = dev->base;
int r = imm_wait(dev);
/*
* Make sure that:
* a) the SCSI bus is BUSY (device still listening)
* b) the device is sending data
*/
if ((r & 0x18) != 0x18) {
imm_fail(dev, DID_ERROR);
return 0;
}
switch (dev->mode) {
case IMM_NIBBLE:
/* 4 bit input, with a loop */
r = imm_nibble_in(ppb, buffer, len);
w_ctr(ppb, 0xc);
break;
case IMM_PS2:
/* 8 bit input, with a loop */
r = imm_byte_in(ppb, buffer, len);
w_ctr(ppb, 0xc);
break;
case IMM_EPP_32:
case IMM_EPP_16:
case IMM_EPP_8:
epp_reset(ppb);
w_ctr(ppb, 0x24);
#ifdef CONFIG_SCSI_IZIP_EPP16
if (!(((long) buffer | len) & 0x01))
insw(ppb + 4, buffer, len >> 1);
#else
if (!(((long) buffer | len) & 0x03))
insl(ppb + 4, buffer, len >> 2);
#endif
else
insb(ppb + 4, buffer, len);
w_ctr(ppb, 0x2c);
r = !(r_str(ppb) & 0x01);
w_ctr(ppb, 0x2c);
ecp_sync(dev);
break;
default:
printk("IMM: bug in imm_ins()\n");
r = 0;
break;
}
return r;
}
static int imm_cpp(unsigned short ppb, unsigned char b)
{
/*
* Comments on udelay values refer to the
* Command Packet Protocol (CPP) timing diagram.
*/
unsigned char s1, s2, s3;
w_ctr(ppb, 0x0c);
udelay(2); /* 1 usec - infinite */
w_dtr(ppb, 0xaa);
udelay(10); /* 7 usec - infinite */
w_dtr(ppb, 0x55);
udelay(10); /* 7 usec - infinite */
w_dtr(ppb, 0x00);
udelay(10); /* 7 usec - infinite */
w_dtr(ppb, 0xff);
udelay(10); /* 7 usec - infinite */
s1 = r_str(ppb) & 0xb8;
w_dtr(ppb, 0x87);
udelay(10); /* 7 usec - infinite */
s2 = r_str(ppb) & 0xb8;
w_dtr(ppb, 0x78);
udelay(10); /* 7 usec - infinite */
s3 = r_str(ppb) & 0x38;
/*
* Values for b are:
* 0000 00aa Assign address aa to current device
* 0010 00aa Select device aa in EPP Winbond mode
* 0010 10aa Select device aa in EPP mode
* 0011 xxxx Deselect all devices
* 0110 00aa Test device aa
* 1101 00aa Select device aa in ECP mode
* 1110 00aa Select device aa in Compatible mode
*/
w_dtr(ppb, b);
udelay(2); /* 1 usec - infinite */
w_ctr(ppb, 0x0c);
udelay(10); /* 7 usec - infinite */
w_ctr(ppb, 0x0d);
udelay(2); /* 1 usec - infinite */
w_ctr(ppb, 0x0c);
udelay(10); /* 7 usec - infinite */
w_dtr(ppb, 0xff);
udelay(10); /* 7 usec - infinite */
/*
* The following table is electrical pin values.
* (BSY is inverted at the CTR register)
*
* BSY ACK POut SEL Fault
* S1 0 X 1 1 1
* S2 1 X 0 1 1
* S3 L X 1 1 S
*
* L => Last device in chain
* S => Selected
*
* Observered values for S1,S2,S3 are:
* Disconnect => f8/58/78
* Connect => f8/58/70
*/
if ((s1 == 0xb8) && (s2 == 0x18) && (s3 == 0x30))
return 1; /* Connected */
if ((s1 == 0xb8) && (s2 == 0x18) && (s3 == 0x38))
return 0; /* Disconnected */
return -1; /* No device present */
}
static inline int imm_connect(imm_struct *dev, int flag)
{
unsigned short ppb = dev->base;
imm_cpp(ppb, 0xe0); /* Select device 0 in compatible mode */
imm_cpp(ppb, 0x30); /* Disconnect all devices */
if ((dev->mode == IMM_EPP_8) ||
(dev->mode == IMM_EPP_16) ||
(dev->mode == IMM_EPP_32))
return imm_cpp(ppb, 0x28); /* Select device 0 in EPP mode */
return imm_cpp(ppb, 0xe0); /* Select device 0 in compatible mode */
}
static void imm_disconnect(imm_struct *dev)
{
imm_cpp(dev->base, 0x30); /* Disconnect all devices */
}
static int imm_select(imm_struct *dev, int target)
{
int k;
unsigned short ppb = dev->base;
/*
* Firstly we want to make sure there is nothing
* holding onto the SCSI bus.
*/
w_ctr(ppb, 0xc);
k = IMM_SELECT_TMO;
do {
k--;
} while ((r_str(ppb) & 0x08) && (k));
if (!k)
return 0;
/*
* Now assert the SCSI ID (HOST and TARGET) on the data bus
*/
w_ctr(ppb, 0x4);
w_dtr(ppb, 0x80 | (1 << target));
udelay(1);
/*
* Deassert SELIN first followed by STROBE
*/
w_ctr(ppb, 0xc);
w_ctr(ppb, 0xd);
/*
* ACK should drop low while SELIN is deasserted.
* FAULT should drop low when the SCSI device latches the bus.
*/
k = IMM_SELECT_TMO;
do {
k--;
}
while (!(r_str(ppb) & 0x08) && (k));
/*
* Place the interface back into a sane state (status mode)
*/
w_ctr(ppb, 0xc);
return (k) ? 1 : 0;
}
static int imm_init(imm_struct *dev)
{
if (imm_connect(dev, 0) != 1)
return -EIO;
imm_reset_pulse(dev->base);
udelay(1000); /* Delay to allow devices to settle */
imm_disconnect(dev);
udelay(1000); /* Another delay to allow devices to settle */
return device_check(dev);
}
static inline int imm_send_command(struct scsi_cmnd *cmd)
{
imm_struct *dev = imm_dev(cmd->device->host);
int k;
/* NOTE: IMM uses byte pairs */
for (k = 0; k < cmd->cmd_len; k += 2)
if (!imm_out(dev, &cmd->cmnd[k], 2))
return 0;
return 1;
}
/*
* The bulk flag enables some optimisations in the data transfer loops,
* it should be true for any command that transfers data in integral
* numbers of sectors.
*
* The driver appears to remain stable if we speed up the parallel port
* i/o in this function, but not elsewhere.
*/
static int imm_completion(struct scsi_cmnd *cmd)
{
/* Return codes:
* -1 Error
* 0 Told to schedule
* 1 Finished data transfer
*/
imm_struct *dev = imm_dev(cmd->device->host);
unsigned short ppb = dev->base;
unsigned long start_jiffies = jiffies;
unsigned char r, v;
int fast, bulk, status;
v = cmd->cmnd[0];
bulk = ((v == READ_6) ||
(v == READ_10) || (v == WRITE_6) || (v == WRITE_10));
/*
* We only get here if the drive is ready to comunicate,
* hence no need for a full imm_wait.
*/
w_ctr(ppb, 0x0c);
r = (r_str(ppb) & 0xb8);
/*
* while (device is not ready to send status byte)
* loop;
*/
while (r != (unsigned char) 0xb8) {
/*
* If we have been running for more than a full timer tick
* then take a rest.
*/
if (time_after(jiffies, start_jiffies + 1))
return 0;
/*
* FAIL if:
* a) Drive status is screwy (!ready && !present)
* b) Drive is requesting/sending more data than expected
*/
if (((r & 0x88) != 0x88) || (cmd->SCp.this_residual <= 0)) {
imm_fail(dev, DID_ERROR);
return -1; /* ERROR_RETURN */
}
/* determine if we should use burst I/O */
if (dev->rd == 0) {
fast = (bulk
&& (cmd->SCp.this_residual >=
IMM_BURST_SIZE)) ? IMM_BURST_SIZE : 2;
status = imm_out(dev, cmd->SCp.ptr, fast);
} else {
fast = (bulk
&& (cmd->SCp.this_residual >=
IMM_BURST_SIZE)) ? IMM_BURST_SIZE : 1;
status = imm_in(dev, cmd->SCp.ptr, fast);
}
cmd->SCp.ptr += fast;
cmd->SCp.this_residual -= fast;
if (!status) {
imm_fail(dev, DID_BUS_BUSY);
return -1; /* ERROR_RETURN */
}
if (cmd->SCp.buffer && !cmd->SCp.this_residual) {
/* if scatter/gather, advance to the next segment */
if (cmd->SCp.buffers_residual--) {
cmd->SCp.buffer++;
cmd->SCp.this_residual =
cmd->SCp.buffer->length;
cmd->SCp.ptr =
page_address(cmd->SCp.buffer->page) +
cmd->SCp.buffer->offset;
/*
* Make sure that we transfer even number of bytes
* otherwise it makes imm_byte_out() messy.
*/
if (cmd->SCp.this_residual & 0x01)
cmd->SCp.this_residual++;
}
}
/* Now check to see if the drive is ready to comunicate */
w_ctr(ppb, 0x0c);
r = (r_str(ppb) & 0xb8);
/* If not, drop back down to the scheduler and wait a timer tick */
if (!(r & 0x80))
return 0;
}
return 1; /* FINISH_RETURN */
}
/*
* Since the IMM itself doesn't generate interrupts, we use
* the scheduler's task queue to generate a stream of call-backs and
* complete the request when the drive is ready.
*/
static void imm_interrupt(void *data)
{
imm_struct *dev = (imm_struct *) data;
struct scsi_cmnd *cmd = dev->cur_cmd;
struct Scsi_Host *host = cmd->device->host;
unsigned long flags;
if (!cmd) {
printk("IMM: bug in imm_interrupt\n");
return;
}
if (imm_engine(dev, cmd)) {
INIT_WORK(&dev->imm_tq, imm_interrupt, (void *) dev);
schedule_delayed_work(&dev->imm_tq, 1);
return;
}
/* Command must of completed hence it is safe to let go... */
#if IMM_DEBUG > 0
switch ((cmd->result >> 16) & 0xff) {
case DID_OK:
break;
case DID_NO_CONNECT:
printk("imm: no device at SCSI ID %i\n", cmd->device->id);
break;
case DID_BUS_BUSY:
printk("imm: BUS BUSY - EPP timeout detected\n");
break;
case DID_TIME_OUT:
printk("imm: unknown timeout\n");
break;
case DID_ABORT:
printk("imm: told to abort\n");
break;
case DID_PARITY:
printk("imm: parity error (???)\n");
break;
case DID_ERROR:
printk("imm: internal driver error\n");
break;
case DID_RESET:
printk("imm: told to reset device\n");
break;
case DID_BAD_INTR:
printk("imm: bad interrupt (???)\n");
break;
default:
printk("imm: bad return code (%02x)\n",
(cmd->result >> 16) & 0xff);
}
#endif
if (cmd->SCp.phase > 1)
imm_disconnect(dev);
imm_pb_dismiss(dev);
spin_lock_irqsave(host->host_lock, flags);
dev->cur_cmd = NULL;
cmd->scsi_done(cmd);
spin_unlock_irqrestore(host->host_lock, flags);
return;
}
static int imm_engine(imm_struct *dev, struct scsi_cmnd *cmd)
{
unsigned short ppb = dev->base;
unsigned char l = 0, h = 0;
int retv, x;
/* First check for any errors that may have occurred
* Here we check for internal errors
*/
if (dev->failed)
return 0;
switch (cmd->SCp.phase) {
case 0: /* Phase 0 - Waiting for parport */
if (time_after(jiffies, dev->jstart + HZ)) {
/*
* We waited more than a second
* for parport to call us
*/
imm_fail(dev, DID_BUS_BUSY);
return 0;
}
return 1; /* wait until imm_wakeup claims parport */
/* Phase 1 - Connected */
case 1:
imm_connect(dev, CONNECT_EPP_MAYBE);
cmd->SCp.phase++;
/* Phase 2 - We are now talking to the scsi bus */
case 2:
if (!imm_select(dev, cmd->device->id)) {
imm_fail(dev, DID_NO_CONNECT);
return 0;
}
cmd->SCp.phase++;
/* Phase 3 - Ready to accept a command */
case 3:
w_ctr(ppb, 0x0c);
if (!(r_str(ppb) & 0x80))
return 1;
if (!imm_send_command(cmd))
return 0;
cmd->SCp.phase++;
/* Phase 4 - Setup scatter/gather buffers */
case 4:
if (cmd->use_sg) {
/* if many buffers are available, start filling the first */
cmd->SCp.buffer =
(struct scatterlist *) cmd->request_buffer;
cmd->SCp.this_residual = cmd->SCp.buffer->length;
cmd->SCp.ptr =
page_address(cmd->SCp.buffer->page) +
cmd->SCp.buffer->offset;
} else {
/* else fill the only available buffer */
cmd->SCp.buffer = NULL;
cmd->SCp.this_residual = cmd->request_bufflen;
cmd->SCp.ptr = cmd->request_buffer;
}
cmd->SCp.buffers_residual = cmd->use_sg - 1;
cmd->SCp.phase++;
if (cmd->SCp.this_residual & 0x01)
cmd->SCp.this_residual++;
/* Phase 5 - Pre-Data transfer stage */
case 5:
/* Spin lock for BUSY */
w_ctr(ppb, 0x0c);
if (!(r_str(ppb) & 0x80))
return 1;
/* Require negotiation for read requests */
x = (r_str(ppb) & 0xb8);
dev->rd = (x & 0x10) ? 1 : 0;
dev->dp = (x & 0x20) ? 0 : 1;
if ((dev->dp) && (dev->rd))
if (imm_negotiate(dev))
return 0;
cmd->SCp.phase++;
/* Phase 6 - Data transfer stage */
case 6:
/* Spin lock for BUSY */
w_ctr(ppb, 0x0c);
if (!(r_str(ppb) & 0x80))
return 1;
if (dev->dp) {
retv = imm_completion(cmd);
if (retv == -1)
return 0;
if (retv == 0)
return 1;
}
cmd->SCp.phase++;
/* Phase 7 - Post data transfer stage */
case 7:
if ((dev->dp) && (dev->rd)) {
if ((dev->mode == IMM_NIBBLE) || (dev->mode == IMM_PS2)) {
w_ctr(ppb, 0x4);
w_ctr(ppb, 0xc);
w_ctr(ppb, 0xe);
w_ctr(ppb, 0x4);
}
}
cmd->SCp.phase++;
/* Phase 8 - Read status/message */
case 8:
/* Check for data overrun */
if (imm_wait(dev) != (unsigned char) 0xb8) {
imm_fail(dev, DID_ERROR);
return 0;
}
if (imm_negotiate(dev))
return 0;
if (imm_in(dev, &l, 1)) { /* read status byte */
/* Check for optional message byte */
if (imm_wait(dev) == (unsigned char) 0xb8)
imm_in(dev, &h, 1);
cmd->result = (DID_OK << 16) + (l & STATUS_MASK);
}
if ((dev->mode == IMM_NIBBLE) || (dev->mode == IMM_PS2)) {
w_ctr(ppb, 0x4);
w_ctr(ppb, 0xc);
w_ctr(ppb, 0xe);
w_ctr(ppb, 0x4);
}
return 0; /* Finished */
break;
default:
printk("imm: Invalid scsi phase\n");
}
return 0;
}
static int imm_queuecommand(struct scsi_cmnd *cmd,
void (*done)(struct scsi_cmnd *))
{
imm_struct *dev = imm_dev(cmd->device->host);
if (dev->cur_cmd) {
printk("IMM: bug in imm_queuecommand\n");
return 0;
}
dev->failed = 0;
dev->jstart = jiffies;
dev->cur_cmd = cmd;
cmd->scsi_done = done;
cmd->result = DID_ERROR << 16; /* default return code */
cmd->SCp.phase = 0; /* bus free */
INIT_WORK(&dev->imm_tq, imm_interrupt, dev);
schedule_work(&dev->imm_tq);
imm_pb_claim(dev);
return 0;
}
/*
* Apparently the disk->capacity attribute is off by 1 sector
* for all disk drives. We add the one here, but it should really
* be done in sd.c. Even if it gets fixed there, this will still
* work.
*/
static int imm_biosparam(struct scsi_device *sdev, struct block_device *dev,
sector_t capacity, int ip[])
{
ip[0] = 0x40;
ip[1] = 0x20;
ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]);
if (ip[2] > 1024) {
ip[0] = 0xff;
ip[1] = 0x3f;
ip[2] = ((unsigned long) capacity + 1) / (ip[0] * ip[1]);
}
return 0;
}
static int imm_abort(struct scsi_cmnd *cmd)
{
imm_struct *dev = imm_dev(cmd->device->host);
/*
* There is no method for aborting commands since Iomega
* have tied the SCSI_MESSAGE line high in the interface
*/
switch (cmd->SCp.phase) {
case 0: /* Do not have access to parport */
case 1: /* Have not connected to interface */
dev->cur_cmd = NULL; /* Forget the problem */
return SUCCESS;
break;