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path: root/drivers/scsi/ppa.c
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-rw-r--r--drivers/scsi/ppa.c1150
1 files changed, 1150 insertions, 0 deletions
diff --git a/drivers/scsi/ppa.c b/drivers/scsi/ppa.c
new file mode 100644
index 000000000000..96b4522523d9
--- /dev/null
+++ b/drivers/scsi/ppa.c
@@ -0,0 +1,1150 @@
+/* ppa.c -- low level driver for the IOMEGA PPA3
+ * parallel port SCSI host adapter.
+ *
+ * (The PPA3 is the embedded controller in the ZIP drive.)
+ *
+ * (c) 1995,1996 Grant R. Guenther, grant@torque.net,
+ * under the terms of the GNU General Public License.
+ *
+ * Current Maintainer: David Campbell (Perth, Western Australia, GMT+0800)
+ * campbell@torque.net
+ */
+
+#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>
+
+
+static void ppa_reset_pulse(unsigned int base);
+
+typedef struct {
+ struct pardevice *dev; /* Parport device entry */
+ int base; /* Actual port address */
+ int mode; /* Transfer mode */
+ struct scsi_cmnd *cur_cmd; /* Current queued command */
+ struct work_struct ppa_tq; /* Polling interrupt stuff */
+ unsigned long jstart; /* Jiffies at start */
+ unsigned long recon_tmo; /* How many usecs to wait for reconnection (6th bit) */
+ unsigned int failed:1; /* Failure flag */
+ unsigned wanted:1; /* Parport sharing busy flag */
+ wait_queue_head_t *waiting;
+ struct Scsi_Host *host;
+ struct list_head list;
+} ppa_struct;
+
+#include "ppa.h"
+
+static inline ppa_struct *ppa_dev(struct Scsi_Host *host)
+{
+ return *(ppa_struct **)&host->hostdata;
+}
+
+static DEFINE_SPINLOCK(arbitration_lock);
+
+static void got_it(ppa_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 ppa_wakeup(void *ref)
+{
+ ppa_struct *dev = (ppa_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);
+ return;
+}
+
+static int ppa_pb_claim(ppa_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 ppa_pb_dismiss(ppa_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 ppa_pb_release(ppa_struct *dev)
+{
+ parport_release(dev->dev);
+}
+
+/*
+ * Start of Chipset kludges
+ */
+
+/* This is to give the ppa driver a way to modify the timings (and other
+ * parameters) by writing to the /proc/scsi/ppa/0 file.
+ * Very simple method really... (To 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 ppa_proc_write(ppa_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;
+ }
+ if ((length > 10) && (strncmp(buffer, "recon_tmo=", 10) == 0)) {
+ x = simple_strtoul(buffer + 10, NULL, 0);
+ dev->recon_tmo = x;
+ printk("ppa: recon_tmo set to %ld\n", x);
+ return length;
+ }
+ printk("ppa /proc: invalid variable\n");
+ return (-EINVAL);
+}
+
+static int ppa_proc_info(struct Scsi_Host *host, char *buffer, char **start, off_t offset, int length, int inout)
+{
+ int len = 0;
+ ppa_struct *dev = ppa_dev(host);
+
+ if (inout)
+ return ppa_proc_write(dev, buffer, length);
+
+ len += sprintf(buffer + len, "Version : %s\n", PPA_VERSION);
+ len +=
+ sprintf(buffer + len, "Parport : %s\n",
+ dev->dev->port->name);
+ len +=
+ sprintf(buffer + len, "Mode : %s\n",
+ PPA_MODE_STRING[dev->mode]);
+#if PPA_DEBUG > 0
+ len +=
+ sprintf(buffer + len, "recon_tmo : %lu\n", dev->recon_tmo);
+#endif
+
+ /* Request for beyond end of buffer */
+ if (offset > length)
+ return 0;
+
+ *start = buffer + offset;
+ len -= offset;
+ if (len > length)
+ len = length;
+ return len;
+}
+
+static int device_check(ppa_struct *dev);
+
+#if PPA_DEBUG > 0
+#define ppa_fail(x,y) printk("ppa: ppa_fail(%i) from %s at line %d\n",\
+ y, __FUNCTION__, __LINE__); ppa_fail_func(x,y);
+static inline void ppa_fail_func(ppa_struct *dev, int error_code)
+#else
+static inline void ppa_fail(ppa_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 ppa_wait(ppa_struct *dev)
+{
+ int k;
+ unsigned short ppb = dev->base;
+ unsigned char r;
+
+ k = PPA_SPIN_TMO;
+ /* Wait for bit 6 and 7 - PJC */
+ for (r = r_str(ppb); ((r & 0xc0) != 0xc0) && (k); k--) {
+ udelay(1);
+ r = r_str(ppb);
+ }
+
+ /*
+ * return some status information.
+ * Semantics: 0xc0 = ZIP wants more data
+ * 0xd0 = ZIP wants to send more data
+ * 0xe0 = ZIP is expecting SCSI command data
+ * 0xf0 = end of transfer, ZIP is sending status
+ */
+ if (k)
+ return (r & 0xf0);
+
+ /* Counter expired - Time out occurred */
+ ppa_fail(dev, DID_TIME_OUT);
+ printk("ppa timeout in ppa_wait\n");
+ return 0; /* command timed out */
+}
+
+/*
+ * 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(ppa_struct *dev)
+{
+ int i, ppb_hi = dev->dev->port->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("ppa: ECP sync failed as data still present in FIFO.\n");
+ }
+}
+
+static int ppa_byte_out(unsigned short base, const char *buffer, int len)
+{
+ int i;
+
+ for (i = len; i; i--) {
+ w_dtr(base, *buffer++);
+ w_ctr(base, 0xe);
+ w_ctr(base, 0xc);
+ }
+ return 1; /* All went well - we hope! */
+}
+
+static int ppa_byte_in(unsigned short base, char *buffer, int len)
+{
+ int i;
+
+ for (i = len; i; i--) {
+ *buffer++ = r_dtr(base);
+ w_ctr(base, 0x27);
+ w_ctr(base, 0x25);
+ }
+ return 1; /* All went well - we hope! */
+}
+
+static int ppa_nibble_in(unsigned short base, char *buffer, int len)
+{
+ for (; len; len--) {
+ unsigned char h;
+
+ w_ctr(base, 0x4);
+ h = r_str(base) & 0xf0;
+ w_ctr(base, 0x6);
+ *buffer++ = h | ((r_str(base) & 0xf0) >> 4);
+ }
+ return 1; /* All went well - we hope! */
+}
+
+static int ppa_out(ppa_struct *dev, char *buffer, int len)
+{
+ int r;
+ unsigned short ppb = dev->base;
+
+ r = ppa_wait(dev);
+
+ if ((r & 0x50) != 0x40) {
+ ppa_fail(dev, DID_ERROR);
+ return 0;
+ }
+ switch (dev->mode) {
+ case PPA_NIBBLE:
+ case PPA_PS2:
+ /* 8 bit output, with a loop */
+ r = ppa_byte_out(ppb, buffer, len);
+ break;
+
+ case PPA_EPP_32:
+ case PPA_EPP_16:
+ case PPA_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;
+
+ default:
+ printk("PPA: bug in ppa_out()\n");
+ r = 0;
+ }
+ return r;
+}
+
+static int ppa_in(ppa_struct *dev, char *buffer, int len)
+{
+ int r;
+ unsigned short ppb = dev->base;
+
+ r = ppa_wait(dev);
+
+ if ((r & 0x50) != 0x50) {
+ ppa_fail(dev, DID_ERROR);
+ return 0;
+ }
+ switch (dev->mode) {
+ case PPA_NIBBLE:
+ /* 4 bit input, with a loop */
+ r = ppa_nibble_in(ppb, buffer, len);
+ w_ctr(ppb, 0xc);
+ break;
+
+ case PPA_PS2:
+ /* 8 bit input, with a loop */
+ w_ctr(ppb, 0x25);
+ r = ppa_byte_in(ppb, buffer, len);
+ w_ctr(ppb, 0x4);
+ w_ctr(ppb, 0xc);
+ break;
+
+ case PPA_EPP_32:
+ case PPA_EPP_16:
+ case PPA_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("PPA: bug in ppa_ins()\n");
+ r = 0;
+ break;
+ }
+ return r;
+}
+
+/* end of ppa_io.h */
+static inline void ppa_d_pulse(unsigned short ppb, unsigned char b)
+{
+ w_dtr(ppb, b);
+ w_ctr(ppb, 0xc);
+ w_ctr(ppb, 0xe);
+ w_ctr(ppb, 0xc);
+ w_ctr(ppb, 0x4);
+ w_ctr(ppb, 0xc);
+}
+
+static void ppa_disconnect(ppa_struct *dev)
+{
+ unsigned short ppb = dev->base;
+
+ ppa_d_pulse(ppb, 0);
+ ppa_d_pulse(ppb, 0x3c);
+ ppa_d_pulse(ppb, 0x20);
+ ppa_d_pulse(ppb, 0xf);
+}
+
+static inline void ppa_c_pulse(unsigned short ppb, unsigned char b)
+{
+ w_dtr(ppb, b);
+ w_ctr(ppb, 0x4);
+ w_ctr(ppb, 0x6);
+ w_ctr(ppb, 0x4);
+ w_ctr(ppb, 0xc);
+}
+
+static inline void ppa_connect(ppa_struct *dev, int flag)
+{
+ unsigned short ppb = dev->base;
+
+ ppa_c_pulse(ppb, 0);
+ ppa_c_pulse(ppb, 0x3c);
+ ppa_c_pulse(ppb, 0x20);
+ if ((flag == CONNECT_EPP_MAYBE) && IN_EPP_MODE(dev->mode))
+ ppa_c_pulse(ppb, 0xcf);
+ else
+ ppa_c_pulse(ppb, 0x8f);
+}
+
+static int ppa_select(ppa_struct *dev, int target)
+{
+ int k;
+ unsigned short ppb = dev->base;
+
+ /*
+ * Bit 6 (0x40) is the device selected bit.
+ * First we must wait till the current device goes off line...
+ */
+ k = PPA_SELECT_TMO;
+ do {
+ k--;
+ udelay(1);
+ } while ((r_str(ppb) & 0x40) && (k));
+ if (!k)
+ return 0;
+
+ w_dtr(ppb, (1 << target));
+ w_ctr(ppb, 0xe);
+ w_ctr(ppb, 0xc);
+ w_dtr(ppb, 0x80); /* This is NOT the initator */
+ w_ctr(ppb, 0x8);
+
+ k = PPA_SELECT_TMO;
+ do {
+ k--;
+ udelay(1);
+ }
+ while (!(r_str(ppb) & 0x40) && (k));
+ if (!k)
+ return 0;
+
+ return 1;
+}
+
+/*
+ * This is based on a trace of what the Iomega DOS 'guest' driver does.
+ * I've tried several different kinds of parallel ports with guest and
+ * coded this to react in the same ways that it does.
+ *
+ * The return value from this function is just a hint about where the
+ * handshaking failed.
+ *
+ */
+static int ppa_init(ppa_struct *dev)
+{
+ int retv;
+ unsigned short ppb = dev->base;
+
+ ppa_disconnect(dev);
+ ppa_connect(dev, CONNECT_NORMAL);
+
+ retv = 2; /* Failed */
+
+ w_ctr(ppb, 0xe);
+ if ((r_str(ppb) & 0x08) == 0x08)
+ retv--;
+
+ w_ctr(ppb, 0xc);
+ if ((r_str(ppb) & 0x08) == 0x00)
+ retv--;
+
+ if (!retv)
+ ppa_reset_pulse(ppb);
+ udelay(1000); /* Allow devices to settle down */
+ ppa_disconnect(dev);
+ udelay(1000); /* Another delay to allow devices to settle */
+
+ if (retv)
+ return -EIO;
+
+ return device_check(dev);
+}
+
+static inline int ppa_send_command(struct scsi_cmnd *cmd)
+{
+ ppa_struct *dev = ppa_dev(cmd->device->host);
+ int k;
+
+ w_ctr(dev->base, 0x0c);
+
+ for (k = 0; k < cmd->cmd_len; k++)
+ if (!ppa_out(dev, &cmd->cmnd[k], 1))
+ 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 ppa_completion(struct scsi_cmnd *cmd)
+{
+ /* Return codes:
+ * -1 Error
+ * 0 Told to schedule
+ * 1 Finished data transfer
+ */
+ ppa_struct *dev = ppa_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 ppa_wait.
+ */
+ r = (r_str(ppb) & 0xf0);
+
+ while (r != (unsigned char) 0xf0) {
+ /*
+ * 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;
+
+ if ((cmd->SCp.this_residual <= 0)) {
+ ppa_fail(dev, DID_ERROR);
+ return -1; /* ERROR_RETURN */
+ }
+
+ /* On some hardware we have SCSI disconnected (6th bit low)
+ * for about 100usecs. It is too expensive to wait a
+ * tick on every loop so we busy wait for no more than
+ * 500usecs to give the drive a chance first. We do not
+ * change things for "normal" hardware since generally
+ * the 6th bit is always high.
+ * This makes the CPU load higher on some hardware
+ * but otherwise we can not get more than 50K/secs
+ * on this problem hardware.
+ */
+ if ((r & 0xc0) != 0xc0) {
+ /* Wait for reconnection should be no more than
+ * jiffy/2 = 5ms = 5000 loops
+ */
+ unsigned long k = dev->recon_tmo;
+ for (; k && ((r = (r_str(ppb) & 0xf0)) & 0xc0) != 0xc0;
+ k--)
+ udelay(1);
+
+ if (!k)
+ return 0;
+ }
+
+ /* determine if we should use burst I/O */
+ fast = (bulk && (cmd->SCp.this_residual >= PPA_BURST_SIZE))
+ ? PPA_BURST_SIZE : 1;
+
+ if (r == (unsigned char) 0xc0)
+ status = ppa_out(dev, cmd->SCp.ptr, fast);
+ else
+ status = ppa_in(dev, cmd->SCp.ptr, fast);
+
+ cmd->SCp.ptr += fast;
+ cmd->SCp.this_residual -= fast;
+
+ if (!status) {
+ ppa_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;
+ }
+ }
+ /* Now check to see if the drive is ready to comunicate */
+ r = (r_str(ppb) & 0xf0);
+ /* If not, drop back down to the scheduler and wait a timer tick */
+ if (!(r & 0x80))
+ return 0;
+ }
+ return 1; /* FINISH_RETURN */
+}
+
+/*
+ * Since the PPA 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 ppa_interrupt(void *data)
+{
+ ppa_struct *dev = (ppa_struct *) data;
+ struct scsi_cmnd *cmd = dev->cur_cmd;
+
+ if (!cmd) {
+ printk("PPA: bug in ppa_interrupt\n");
+ return;
+ }
+ if (ppa_engine(dev, cmd)) {
+ dev->ppa_tq.data = (void *) dev;
+ schedule_delayed_work(&dev->ppa_tq, 1);
+ return;
+ }
+ /* Command must of completed hence it is safe to let go... */
+#if PPA_DEBUG > 0
+ switch ((cmd->result >> 16) & 0xff) {
+ case DID_OK:
+ break;
+ case DID_NO_CONNECT:
+ printk("ppa: no device at SCSI ID %i\n", cmd->device->target);
+ break;
+ case DID_BUS_BUSY:
+ printk("ppa: BUS BUSY - EPP timeout detected\n");
+ break;
+ case DID_TIME_OUT:
+ printk("ppa: unknown timeout\n");
+ break;
+ case DID_ABORT:
+ printk("ppa: told to abort\n");
+ break;
+ case DID_PARITY:
+ printk("ppa: parity error (???)\n");
+ break;
+ case DID_ERROR:
+ printk("ppa: internal driver error\n");
+ break;
+ case DID_RESET:
+ printk("ppa: told to reset device\n");
+ break;
+ case DID_BAD_INTR:
+ printk("ppa: bad interrupt (???)\n");
+ break;
+ default:
+ printk("ppa: bad return code (%02x)\n",
+ (cmd->result >> 16) & 0xff);
+ }
+#endif
+
+ if (cmd->SCp.phase > 1)
+ ppa_disconnect(dev);
+
+ ppa_pb_dismiss(dev);
+
+ dev->cur_cmd = NULL;
+
+ cmd->scsi_done(cmd);
+}
+
+static int ppa_engine(ppa_struct *dev, struct scsi_cmnd *cmd)
+{
+ unsigned short ppb = dev->base;
+ unsigned char l = 0, h = 0;
+ int retv;
+
+ /* First check for any errors that may of 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
+ */
+ ppa_fail(dev, DID_BUS_BUSY);
+ return 0;
+ }
+ return 1; /* wait until ppa_wakeup claims parport */
+ case 1: /* Phase 1 - Connected */
+ { /* Perform a sanity check for cable unplugged */
+ int retv = 2; /* Failed */
+
+ ppa_connect(dev, CONNECT_EPP_MAYBE);
+
+ w_ctr(ppb, 0xe);
+ if ((r_str(ppb) & 0x08) == 0x08)
+ retv--;
+
+ w_ctr(ppb, 0xc);
+ if ((r_str(ppb) & 0x08) == 0x00)
+ retv--;
+
+ if (retv) {
+ if ((jiffies - dev->jstart) > (1 * HZ)) {
+ printk
+ ("ppa: Parallel port cable is unplugged!!\n");
+ ppa_fail(dev, DID_BUS_BUSY);
+ return 0;
+ } else {
+ ppa_disconnect(dev);
+ return 1; /* Try again in a jiffy */
+ }
+ }
+ cmd->SCp.phase++;
+ }
+
+ case 2: /* Phase 2 - We are now talking to the scsi bus */
+ if (!ppa_select(dev, cmd->device->id)) {
+ ppa_fail(dev, DID_NO_CONNECT);
+ return 0;
+ }
+ cmd->SCp.phase++;
+
+ case 3: /* Phase 3 - Ready to accept a command */
+ w_ctr(ppb, 0x0c);
+ if (!(r_str(ppb) & 0x80))
+ return 1;
+
+ if (!ppa_send_command(cmd))
+ return 0;
+ cmd->SCp.phase++;
+
+ case 4: /* Phase 4 - Setup scatter/gather buffers */
+ 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++;
+
+ case 5: /* Phase 5 - Data transfer stage */
+ w_ctr(ppb, 0x0c);
+ if (!(r_str(ppb) & 0x80))
+ return 1;
+
+ retv = ppa_completion(cmd);
+ if (retv == -1)
+ return 0;
+ if (retv == 0)
+ return 1;
+ cmd->SCp.phase++;
+
+ case 6: /* Phase 6 - Read status/message */
+ cmd->result = DID_OK << 16;
+ /* Check for data overrun */
+ if (ppa_wait(dev) != (unsigned char) 0xf0) {
+ ppa_fail(dev, DID_ERROR);
+ return 0;
+ }
+ if (ppa_in(dev, &l, 1)) { /* read status byte */
+ /* Check for optional message byte */
+ if (ppa_wait(dev) == (unsigned char) 0xf0)
+ ppa_in(dev, &h, 1);
+ cmd->result =
+ (DID_OK << 16) + (h << 8) + (l & STATUS_MASK);
+ }
+ return 0; /* Finished */
+ break;
+
+ default:
+ printk("ppa: Invalid scsi phase\n");
+ }
+ return 0;
+}
+
+static int ppa_queuecommand(struct scsi_cmnd *cmd,
+ void (*done) (struct scsi_cmnd *))
+{
+ ppa_struct *dev = ppa_dev(cmd->device->host);
+
+ if (dev->cur_cmd) {
+ printk("PPA: bug in ppa_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 */
+
+ dev->ppa_tq.data = dev;
+ schedule_work(&dev->ppa_tq);
+
+ ppa_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 ppa_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]);
+ if (ip[2] > 1023)
+ ip[2] = 1023;
+ }
+ return 0;
+}
+
+static int ppa_abort(struct scsi_cmnd *cmd)
+{
+ ppa_struct *dev = ppa_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 ppa_reset_pulse(unsigned int base)
+{
+ w_dtr(base, 0x40);
+ w_ctr(base, 0x8);
+ udelay(30);
+ w_ctr(base, 0xc);
+}
+
+static int ppa_reset(struct scsi_cmnd *cmd)
+{
+ ppa_struct *dev = ppa_dev(cmd->device->host);
+
+ if (cmd->SCp.phase)
+ ppa_disconnect(dev);
+ dev->cur_cmd = NULL; /* Forget the problem */
+
+ ppa_connect(dev, CONNECT_NORMAL);
+ ppa_reset_pulse(dev->base);
+ udelay(1000); /* device settle delay */
+ ppa_disconnect(dev);
+ udelay(1000); /* device settle delay */
+ return SUCCESS;
+}
+
+static int device_check(ppa_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 = PPA_EPP_32;
+
+ second_pass:
+ ppa_connect(dev, CONNECT_EPP_MAYBE);
+ /* Select SCSI device */
+ if (!ppa_select(dev, loop)) {
+ ppa_disconnect(dev);
+ continue;
+ }
+ printk("ppa: Found device at ID %i, Attempting to use %s\n",
+ loop, PPA_MODE_STRING[dev->mode]);
+
+ /* Send SCSI command */
+ status = 1;
+ w_ctr(ppb, 0x0c);
+ for (l = 0; (l < 6) && (status); l++)
+ status = ppa_out(dev, cmd, 1);
+
+ if (!status) {
+ ppa_disconnect(dev);
+ ppa_connect(dev, CONNECT_EPP_MAYBE);
+ w_dtr(ppb, 0x40);
+ w_ctr(ppb, 0x08);
+ udelay(30);
+ w_ctr(ppb, 0x0c);
+ udelay(1000);
+ ppa_disconnect(dev);
+ udelay(1000);
+ if (dev->mode == PPA_EPP_32) {
+ dev->mode = old_mode;
+ goto second_pass;
+ }
+ return -EIO;
+ }
+ w_ctr(ppb, 0x0c);
+ k = 1000000; /* 1 Second */
+ do {
+ l = r_str(ppb);
+ k--;
+ udelay(1);
+ } while (!(l & 0x80) && (k));
+
+ l &= 0xf0;
+
+ if (l != 0xf0) {
+ ppa_disconnect(dev);
+ ppa_connect(dev, CONNECT_EPP_MAYBE);
+ ppa_reset_pulse(ppb);
+ udelay(1000);
+ ppa_disconnect(dev);
+ udelay(1000);
+ if (dev->mode == PPA_EPP_32) {
+ dev->mode = old_mode;
+ goto second_pass;
+ }
+ return -EIO;
+ }
+ ppa_disconnect(dev);
+ printk("ppa: Communication established with ID %i using %s\n",
+ loop, PPA_MODE_STRING[dev->mode]);
+ ppa_connect(dev, CONNECT_EPP_MAYBE);
+ ppa_reset_pulse(ppb);
+ udelay(1000);
+ ppa_disconnect(dev);
+ udelay(1000);
+ return 0;
+ }
+ return -ENODEV;
+}
+
+static struct scsi_host_template ppa_template = {
+ .module = THIS_MODULE,
+ .proc_name = "ppa",
+ .proc_info = ppa_proc_info,
+ .name = "Iomega VPI0 (ppa) interface",
+ .queuecommand = ppa_queuecommand,
+ .eh_abort_handler = ppa_abort,
+ .eh_bus_reset_handler = ppa_reset,
+ .eh_host_reset_handler = ppa_reset,
+ .bios_param = ppa_biosparam,
+ .this_id = -1,
+ .sg_tablesize = SG_ALL,
+ .cmd_per_lun = 1,
+ .use_clustering = ENABLE_CLUSTERING,
+ .can_queue = 1,
+};
+
+/***************************************************************************
+ * Parallel port probing routines *
+ ***************************************************************************/
+
+static LIST_HEAD(ppa_hosts);
+
+static int __ppa_attach(struct parport *pb)
+{
+ struct Scsi_Host *host;
+ DECLARE_WAIT_QUEUE_HEAD(waiting);
+ DEFINE_WAIT(wait);
+ ppa_struct *dev;
+ int ports;
+ int modes, ppb, ppb_hi;
+ int err = -ENOMEM;
+
+ dev = kmalloc(sizeof(ppa_struct), GFP_KERNEL);
+ if (!dev)
+ return -ENOMEM;
+ memset(dev, 0, sizeof(ppa_struct));
+ dev->base = -1;
+ dev->mode = PPA_AUTODETECT;
+ dev->recon_tmo = PPA_RECON_TMO;
+ init_waitqueue_head(&waiting);
+ dev->dev = parport_register_device(pb, "ppa", NULL, ppa_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 (ppa_pb_claim(dev))
+ schedule_timeout(3 * HZ);
+ if (dev->wanted) {
+ printk(KERN_ERR "ppa%d: failed to claim parport because "
+ "a pardevice is owning the port for too long "
+ "time!\n", pb->number);
+ ppa_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;
+ ppb_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 = PPA_NIBBLE;
+
+ if (modes & PARPORT_MODE_TRISTATE)
+ dev->mode = PPA_PS2;
+
+ if (modes & PARPORT_MODE_ECP) {
+ w_ecr(ppb_hi, 0x20);
+ dev->mode = PPA_PS2;
+ }
+ if ((modes & PARPORT_MODE_EPP) && (modes & PARPORT_MODE_ECP))
+ w_ecr(ppb_hi, 0x80);
+
+ /* Done configuration */
+
+ err = ppa_init(dev);
+ ppa_pb_release(dev);
+
+ if (err)
+ goto out1;
+
+ /* now the glue ... */
+ if (dev->mode == PPA_NIBBLE || dev->mode == PPA_PS2)
+ ports = 3;
+ else
+ ports = 8;
+
+ INIT_WORK(&dev->ppa_tq, ppa_interrupt, dev);
+
+ err = -ENOMEM;
+ host = scsi_host_alloc(&ppa_template, sizeof(ppa_struct *));
+ if (!host)
+ goto out1;
+ host->io_port = pb->base;
+ host->n_io_port = ports;
+ host->dma_channel = -1;
+ host->unique_id = pb->number;
+ *(ppa_struct **)&host->hostdata = dev;
+ dev->host = host;
+ list_add_tail(&dev->list, &ppa_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 ppa_attach(struct parport *pb)
+{
+ __ppa_attach(pb);
+}
+
+static void ppa_detach(struct parport *pb)
+{
+ ppa_struct *dev;
+ list_for_each_entry(dev, &ppa_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 ppa_driver = {
+ .name = "ppa",
+ .attach = ppa_attach,
+ .detach = ppa_detach,
+};
+
+static int __init ppa_driver_init(void)
+{
+ printk("ppa: Version %s\n", PPA_VERSION);
+ return parport_register_driver(&ppa_driver);
+}
+
+static void __exit ppa_driver_exit(void)
+{
+ parport_unregister_driver(&ppa_driver);
+}
+
+module_init(ppa_driver_init);
+module_exit(ppa_driver_exit);
+MODULE_LICENSE("GPL");