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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/scsi/imm.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/scsi/imm.c')
-rw-r--r--drivers/scsi/imm.c1300
1 files changed, 1300 insertions, 0 deletions
diff --git a/drivers/scsi/imm.c b/drivers/scsi/imm.c
new file mode 100644
index 000000000000..be7f2ca0183f
--- /dev/null
+++ b/drivers/scsi/imm.c
@@ -0,0 +1,1300 @@
+/* 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;
+ 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);
+ udelay(1000); /* device settle delay */
+ imm_disconnect(dev);
+ udelay(1000); /* 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;
+}
+
+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,
+ .unchecked_isa_dma = 1, /* imm cannot deal with highmem, so
+ * this is an easy trick to ensure
+ * all io pages for this host reside
+ * in low memory */
+};
+
+/***************************************************************************
+ * 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(waiting);
+ DEFINE_WAIT(wait);
+ int ports;
+ int modes, ppb;
+ int err = -ENOMEM;
+
+ init_waitqueue_head(&waiting);
+
+ dev = kmalloc(sizeof(imm_struct), GFP_KERNEL);
+ if (!dev)
+ return -ENOMEM;
+
+ memset(dev, 0, sizeof(imm_struct));
+
+ 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_WORK(&dev->imm_tq, imm_interrupt, dev);
+
+ 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");