diff options
Diffstat (limited to 'drivers/scsi/ppa.c')
| -rw-r--r-- | drivers/scsi/ppa.c | 1165 |
1 files changed, 1165 insertions, 0 deletions
diff --git a/drivers/scsi/ppa.c b/drivers/scsi/ppa.c new file mode 100644 index 000000000..aa41f7ac9 --- /dev/null +++ b/drivers/scsi/ppa.c @@ -0,0 +1,1165 @@ +/* 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. + * + */ + +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/blkdev.h> +#include <linux/parport.h> +#include <linux/workqueue.h> +#include <linux/delay.h> +#include <linux/jiffies.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 delayed_work 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 */ + unsigned int dev_no; /* Device number */ + 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_write_info(struct Scsi_Host *host, char *buffer, int length) +{ + ppa_struct *dev = ppa_dev(host); + 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(KERN_INFO "ppa: recon_tmo set to %ld\n", x); + return length; + } + printk(KERN_WARNING "ppa /proc: invalid variable\n"); + return -EINVAL; +} + +static int ppa_show_info(struct seq_file *m, struct Scsi_Host *host) +{ + ppa_struct *dev = ppa_dev(host); + + seq_printf(m, "Version : %s\n", PPA_VERSION); + seq_printf(m, "Parport : %s\n", dev->dev->port->name); + seq_printf(m, "Mode : %s\n", PPA_MODE_STRING[dev->mode]); +#if PPA_DEBUG > 0 + seq_printf(m, "recon_tmo : %lu\n", dev->recon_tmo); +#endif + return 0; +} + +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, __func__, __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(KERN_WARNING "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(KERN_WARNING "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(KERN_ERR "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(KERN_ERR "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 = sg_next(cmd->SCp.buffer); + cmd->SCp.this_residual = + cmd->SCp.buffer->length; + cmd->SCp.ptr = sg_virt(cmd->SCp.buffer); + } + } + /* 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(struct work_struct *work) +{ + ppa_struct *dev = container_of(work, ppa_struct, ppa_tq.work); + struct scsi_cmnd *cmd = dev->cur_cmd; + + if (!cmd) { + printk(KERN_ERR "PPA: bug in ppa_interrupt\n"); + return; + } + if (ppa_engine(dev, cmd)) { + 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(KERN_DEBUG "ppa: no device at SCSI ID %i\n", cmd->device->target); + break; + case DID_BUS_BUSY: + printk(KERN_DEBUG "ppa: BUS BUSY - EPP timeout detected\n"); + break; + case DID_TIME_OUT: + printk(KERN_DEBUG "ppa: unknown timeout\n"); + break; + case DID_ABORT: + printk(KERN_DEBUG "ppa: told to abort\n"); + break; + case DID_PARITY: + printk(KERN_DEBUG "ppa: parity error (???)\n"); + break; + case DID_ERROR: + printk(KERN_DEBUG "ppa: internal driver error\n"); + break; + case DID_RESET: + printk(KERN_DEBUG "ppa: told to reset device\n"); + break; + case DID_BAD_INTR: + printk(KERN_WARNING "ppa: bad interrupt (???)\n"); + break; + default: + printk(KERN_WARNING "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 (time_after(jiffies, dev->jstart + (1 * HZ))) { + printk(KERN_ERR "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++; + } + fallthrough; + + case 2: /* Phase 2 - We are now talking to the scsi bus */ + if (!ppa_select(dev, scmd_id(cmd))) { + ppa_fail(dev, DID_NO_CONNECT); + return 0; + } + cmd->SCp.phase++; + fallthrough; + + 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++; + fallthrough; + + case 4: /* Phase 4 - Setup scatter/gather buffers */ + 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++; + fallthrough; + + 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++; + fallthrough; + + 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 */ + + default: + printk(KERN_ERR "ppa: Invalid scsi phase\n"); + } + return 0; +} + +static int ppa_queuecommand_lck(struct scsi_cmnd *cmd, + void (*done) (struct scsi_cmnd *)) +{ + ppa_struct *dev = ppa_dev(cmd->device->host); + + if (dev->cur_cmd) { + printk(KERN_ERR "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 */ + + schedule_delayed_work(&dev->ppa_tq, 0); + + ppa_pb_claim(dev); + + return 0; +} + +static DEF_SCSI_QCMD(ppa_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 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; + default: /* SCSI command sent, can not abort */ + return FAILED; + } +} + +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); + mdelay(1); /* device settle delay */ + ppa_disconnect(dev); + mdelay(1); /* 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 u8 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(KERN_INFO "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(KERN_INFO "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 int ppa_adjust_queue(struct scsi_device *device) +{ + blk_queue_bounce_limit(device->request_queue, BLK_BOUNCE_HIGH); + return 0; +} + +static struct scsi_host_template ppa_template = { + .module = THIS_MODULE, + .proc_name = "ppa", + .show_info = ppa_show_info, + .write_info = ppa_write_info, + .name = "Iomega VPI0 (ppa) interface", + .queuecommand = ppa_queuecommand, + .eh_abort_handler = ppa_abort, + .eh_host_reset_handler = ppa_reset, + .bios_param = ppa_biosparam, + .this_id = -1, + .sg_tablesize = SG_ALL, + .can_queue = 1, + .slave_alloc = ppa_adjust_queue, +}; + +/*************************************************************************** + * Parallel port probing routines * + ***************************************************************************/ + +static LIST_HEAD(ppa_hosts); + +/* + * Finds the first available device number that can be alloted to the + * new ppa device and returns the address of the previous node so that + * we can add to the tail and have a list in the ascending order. + */ + +static inline ppa_struct *find_parent(void) +{ + ppa_struct *dev, *par = NULL; + unsigned int cnt = 0; + + if (list_empty(&ppa_hosts)) + return NULL; + + list_for_each_entry(dev, &ppa_hosts, list) { + if (dev->dev_no != cnt) + return par; + cnt++; + par = dev; + } + + return par; +} + +static int __ppa_attach(struct parport *pb) +{ + struct Scsi_Host *host; + DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting); + DEFINE_WAIT(wait); + ppa_struct *dev, *temp; + int ports; + int modes, ppb, ppb_hi; + int err = -ENOMEM; + struct pardev_cb ppa_cb; + + dev = kzalloc(sizeof(ppa_struct), GFP_KERNEL); + if (!dev) + return -ENOMEM; + dev->base = -1; + dev->mode = PPA_AUTODETECT; + dev->recon_tmo = PPA_RECON_TMO; + init_waitqueue_head(&waiting); + temp = find_parent(); + if (temp) + dev->dev_no = temp->dev_no + 1; + + memset(&ppa_cb, 0, sizeof(ppa_cb)); + ppa_cb.private = dev; + ppa_cb.wakeup = ppa_wakeup; + + dev->dev = parport_register_dev_model(pb, "ppa", &ppa_cb, dev->dev_no); + + 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_DELAYED_WORK(&dev->ppa_tq, ppa_interrupt); + + 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", + .match_port = ppa_attach, + .detach = ppa_detach, + .devmodel = true, +}; + +static int __init ppa_driver_init(void) +{ + printk(KERN_INFO "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"); |