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linux/drivers/scsi/imm.c
Jeff Garzik f281233d3e SCSI host lock push-down 
Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.

The patch below presents a simple SCSI host lock push-down as an
equivalent transformation.  No locking or other behavior should change
with this patch.  All existing bugs and locking orders are preserved.

Additionally, add one parameter to queuecommand,
	struct Scsi_Host *
and remove one parameter from queuecommand,
	void (*done)(struct scsi_cmnd *)

Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.

Minimal code disturbance was attempted with this change.  Most drivers
needed only two one-line modifications for their host lock push-down.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-11-16 13:33:23 -08:00

1287 lines
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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.)
*
* 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/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/parport.h>
#include <linux/workqueue.h>
#include <linux/delay.h>
#include <linux/slab.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 delayed_work 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, __func__, __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);
mdelay(1); /* Delay to allow devices to settle */
imm_disconnect(dev);
mdelay(1); /* 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 = sg_virt(cmd->SCp.buffer);
/*
* 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(struct work_struct *work)
{
imm_struct *dev = container_of(work, imm_struct, imm_tq.work);
struct scsi_cmnd *cmd = dev->cur_cmd;
struct Scsi_Host *host = cmd->device->host;
unsigned long flags;
if (imm_engine(dev, cmd)) {
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, scmd_id(cmd))) {
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 (scsi_bufflen(cmd)) {
cmd->SCp.buffer = scsi_sglist(cmd);
cmd->SCp.this_residual = cmd->SCp.buffer->length;
cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
} else {
cmd->SCp.buffer = NULL;
cmd->SCp.this_residual = 0;
cmd->SCp.ptr = NULL;
}
cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 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_lck(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 */
schedule_delayed_work(&dev->imm_tq, 0);
imm_pb_claim(dev);
return 0;
}
static DEF_SCSI_QCMD(imm_queuecommand)
/*
* 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;
default: /* SCSI command sent, can not abort */
return FAILED;
break;
}
}
static void imm_reset_pulse(unsigned int base)
{
w_ctr(base, 0x04);
w_dtr(base, 0x40);
udelay(1);
w_ctr(base, 0x0c);
w_ctr(base, 0x0d);
udelay(50);
w_ctr(base, 0x0c);
w_ctr(base, 0x04);
}
static int imm_reset(struct scsi_cmnd *cmd)
{
imm_struct *dev = imm_dev(cmd->device->host);
if (cmd->SCp.phase)
imm_disconnect(dev);
dev->cur_cmd = NULL; /* Forget the problem */
imm_connect(dev, CONNECT_NORMAL);
imm_reset_pulse(dev->base);
mdelay(1); /* device settle delay */
imm_disconnect(dev);
mdelay(1); /* device settle delay */
return SUCCESS;
}
static int device_check(imm_struct *dev)
{
/* This routine looks for a device and then attempts to use EPP
to send a command. If all goes as planned then EPP is available. */
static char cmd[6] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
int loop, old_mode, status, k, ppb = dev->base;
unsigned char l;
old_mode = dev->mode;
for (loop = 0; loop < 8; loop++) {
/* Attempt to use EPP for Test Unit Ready */
if ((ppb & 0x0007) == 0x0000)
dev->mode = IMM_EPP_32;
second_pass:
imm_connect(dev, CONNECT_EPP_MAYBE);
/* Select SCSI device */
if (!imm_select(dev, loop)) {
imm_disconnect(dev);
continue;
}
printk("imm: Found device at ID %i, Attempting to use %s\n",
loop, IMM_MODE_STRING[dev->mode]);
/* Send SCSI command */
status = 1;
w_ctr(ppb, 0x0c);
for (l = 0; (l < 3) && (status); l++)
status = imm_out(dev, &cmd[l << 1], 2);
if (!status) {
imm_disconnect(dev);
imm_connect(dev, CONNECT_EPP_MAYBE);
imm_reset_pulse(dev->base);
udelay(1000);
imm_disconnect(dev);
udelay(1000);
if (dev->mode == IMM_EPP_32) {
dev->mode = old_mode;
goto second_pass;
}
printk("imm: Unable to establish communication\n");
return -EIO;
}
w_ctr(ppb, 0x0c);
k = 1000000; /* 1 Second */
do {
l = r_str(ppb);
k--;
udelay(1);
} while (!(l & 0x80) && (k));
l &= 0xb8;
if (l != 0xb8) {
imm_disconnect(dev);
imm_connect(dev, CONNECT_EPP_MAYBE);
imm_reset_pulse(dev->base);
udelay(1000);
imm_disconnect(dev);
udelay(1000);
if (dev->mode == IMM_EPP_32) {
dev->mode = old_mode;
goto second_pass;
}
printk
("imm: Unable to establish communication\n");
return -EIO;
}
imm_disconnect(dev);
printk
("imm: Communication established at 0x%x with ID %i using %s\n",
ppb, loop, IMM_MODE_STRING[dev->mode]);
imm_connect(dev, CONNECT_EPP_MAYBE);
imm_reset_pulse(dev->base);
udelay(1000);
imm_disconnect(dev);
udelay(1000);
return 0;
}
printk("imm: No devices found\n");
return -ENODEV;
}
/*
* imm cannot deal with highmem, so this causes all IO pages for this host
* to reside in low memory (hence mapped)
*/
static int imm_adjust_queue(struct scsi_device *device)
{
blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH);
return 0;
}
static struct scsi_host_template imm_template = {
.module = THIS_MODULE,
.proc_name = "imm",
.proc_info = imm_proc_info,
.name = "Iomega VPI2 (imm) interface",
.queuecommand = imm_queuecommand,
.eh_abort_handler = imm_abort,
.eh_bus_reset_handler = imm_reset,
.eh_host_reset_handler = imm_reset,
.bios_param = imm_biosparam,
.this_id = 7,
.sg_tablesize = SG_ALL,
.cmd_per_lun = 1,
.use_clustering = ENABLE_CLUSTERING,
.can_queue = 1,
.slave_alloc = imm_adjust_queue,
};
/***************************************************************************
* Parallel port probing routines *
***************************************************************************/
static LIST_HEAD(imm_hosts);
static int __imm_attach(struct parport *pb)
{
struct Scsi_Host *host;
imm_struct *dev;
DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting);
DEFINE_WAIT(wait);
int ports;
int modes, ppb;
int err = -ENOMEM;
init_waitqueue_head(&waiting);
dev = kzalloc(sizeof(imm_struct), GFP_KERNEL);
if (!dev)
return -ENOMEM;
dev->base = -1;
dev->mode = IMM_AUTODETECT;
INIT_LIST_HEAD(&dev->list);
dev->dev = parport_register_device(pb, "imm", NULL, imm_wakeup,
NULL, 0, dev);
if (!dev->dev)
goto out;
/* Claim the bus so it remembers what we do to the control
* registers. [ CTR and ECP ]
*/
err = -EBUSY;
dev->waiting = &waiting;
prepare_to_wait(&waiting, &wait, TASK_UNINTERRUPTIBLE);
if (imm_pb_claim(dev))
schedule_timeout(3 * HZ);
if (dev->wanted) {
printk(KERN_ERR "imm%d: failed to claim parport because "
"a pardevice is owning the port for too long "
"time!\n", pb->number);
imm_pb_dismiss(dev);
dev->waiting = NULL;
finish_wait(&waiting, &wait);
goto out1;
}
dev->waiting = NULL;
finish_wait(&waiting, &wait);
ppb = dev->base = dev->dev->port->base;
dev->base_hi = dev->dev->port->base_hi;
w_ctr(ppb, 0x0c);
modes = dev->dev->port->modes;
/* Mode detection works up the chain of speed
* This avoids a nasty if-then-else-if-... tree
*/
dev->mode = IMM_NIBBLE;
if (modes & PARPORT_MODE_TRISTATE)
dev->mode = IMM_PS2;
/* Done configuration */
err = imm_init(dev);
imm_pb_release(dev);
if (err)
goto out1;
/* now the glue ... */
if (dev->mode == IMM_NIBBLE || dev->mode == IMM_PS2)
ports = 3;
else
ports = 8;
INIT_DELAYED_WORK(&dev->imm_tq, imm_interrupt);
err = -ENOMEM;
host = scsi_host_alloc(&imm_template, sizeof(imm_struct *));
if (!host)
goto out1;
host->io_port = pb->base;
host->n_io_port = ports;
host->dma_channel = -1;
host->unique_id = pb->number;
*(imm_struct **)&host->hostdata = dev;
dev->host = host;
list_add_tail(&dev->list, &imm_hosts);
err = scsi_add_host(host, NULL);
if (err)
goto out2;
scsi_scan_host(host);
return 0;
out2:
list_del_init(&dev->list);
scsi_host_put(host);
out1:
parport_unregister_device(dev->dev);
out:
kfree(dev);
return err;
}
static void imm_attach(struct parport *pb)
{
__imm_attach(pb);
}
static void imm_detach(struct parport *pb)
{
imm_struct *dev;
list_for_each_entry(dev, &imm_hosts, list) {
if (dev->dev->port == pb) {
list_del_init(&dev->list);
scsi_remove_host(dev->host);
scsi_host_put(dev->host);
parport_unregister_device(dev->dev);
kfree(dev);
break;
}
}
}
static struct parport_driver imm_driver = {
.name = "imm",
.attach = imm_attach,
.detach = imm_detach,
};
static int __init imm_driver_init(void)
{
printk("imm: Version %s\n", IMM_VERSION);
return parport_register_driver(&imm_driver);
}
static void __exit imm_driver_exit(void)
{
parport_unregister_driver(&imm_driver);
}
module_init(imm_driver_init);
module_exit(imm_driver_exit);
MODULE_LICENSE("GPL");
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