diff options
Diffstat (limited to 'drivers/block/paride/pg.c')
| -rw-r--r-- | drivers/block/paride/pg.c | 726 |
1 files changed, 726 insertions, 0 deletions
diff --git a/drivers/block/paride/pg.c b/drivers/block/paride/pg.c new file mode 100644 index 000000000..876d0c3ea --- /dev/null +++ b/drivers/block/paride/pg.c @@ -0,0 +1,726 @@ +/* + pg.c (c) 1998 Grant R. Guenther <grant@torque.net> + Under the terms of the GNU General Public License. + + The pg driver provides a simple character device interface for + sending ATAPI commands to a device. With the exception of the + ATAPI reset operation, all operations are performed by a pair + of read and write operations to the appropriate /dev/pgN device. + A write operation delivers a command and any outbound data in + a single buffer. Normally, the write will succeed unless the + device is offline or malfunctioning, or there is already another + command pending. If the write succeeds, it should be followed + immediately by a read operation, to obtain any returned data and + status information. A read will fail if there is no operation + in progress. + + As a special case, the device can be reset with a write operation, + and in this case, no following read is expected, or permitted. + + There are no ioctl() operations. Any single operation + may transfer at most PG_MAX_DATA bytes. Note that the driver must + copy the data through an internal buffer. In keeping with all + current ATAPI devices, command packets are assumed to be exactly + 12 bytes in length. + + To permit future changes to this interface, the headers in the + read and write buffers contain a single character "magic" flag. + Currently this flag must be the character "P". + + By default, the driver will autoprobe for a single parallel + port ATAPI device, but if their individual parameters are + specified, the driver can handle up to 4 devices. + + To use this device, you must have the following device + special files defined: + + /dev/pg0 c 97 0 + /dev/pg1 c 97 1 + /dev/pg2 c 97 2 + /dev/pg3 c 97 3 + + (You'll need to change the 97 to something else if you use + the 'major' parameter to install the driver on a different + major number.) + + The behaviour of the pg driver can be altered by setting + some parameters from the insmod command line. The following + parameters are adjustable: + + drive0 These four arguments can be arrays of + drive1 1-6 integers as follows: + drive2 + drive3 <prt>,<pro>,<uni>,<mod>,<slv>,<dly> + + Where, + + <prt> is the base of the parallel port address for + the corresponding drive. (required) + + <pro> is the protocol number for the adapter that + supports this drive. These numbers are + logged by 'paride' when the protocol modules + are initialised. (0 if not given) + + <uni> for those adapters that support chained + devices, this is the unit selector for the + chain of devices on the given port. It should + be zero for devices that don't support chaining. + (0 if not given) + + <mod> this can be -1 to choose the best mode, or one + of the mode numbers supported by the adapter. + (-1 if not given) + + <slv> ATAPI devices can be jumpered to master or slave. + Set this to 0 to choose the master drive, 1 to + choose the slave, -1 (the default) to choose the + first drive found. + + <dly> some parallel ports require the driver to + go more slowly. -1 sets a default value that + should work with the chosen protocol. Otherwise, + set this to a small integer, the larger it is + the slower the port i/o. In some cases, setting + this to zero will speed up the device. (default -1) + + major You may use this parameter to overide the + default major number (97) that this driver + will use. Be sure to change the device + name as well. + + name This parameter is a character string that + contains the name the kernel will use for this + device (in /proc output, for instance). + (default "pg"). + + verbose This parameter controls the amount of logging + that is done by the driver. Set it to 0 for + quiet operation, to 1 to enable progress + messages while the driver probes for devices, + or to 2 for full debug logging. (default 0) + + If this driver is built into the kernel, you can use + the following command line parameters, with the same values + as the corresponding module parameters listed above: + + pg.drive0 + pg.drive1 + pg.drive2 + pg.drive3 + + In addition, you can use the parameter pg.disable to disable + the driver entirely. + +*/ + +/* Changes: + + 1.01 GRG 1998.06.16 Bug fixes + 1.02 GRG 1998.09.24 Added jumbo support + +*/ + +#define PG_VERSION "1.02" +#define PG_MAJOR 97 +#define PG_NAME "pg" +#define PG_UNITS 4 + +#ifndef PI_PG +#define PI_PG 4 +#endif + +#include <linux/types.h> +/* Here are things one can override from the insmod command. + Most are autoprobed by paride unless set here. Verbose is 0 + by default. + +*/ + +static int verbose; +static int major = PG_MAJOR; +static char *name = PG_NAME; +static int disable = 0; + +static int drive0[6] = { 0, 0, 0, -1, -1, -1 }; +static int drive1[6] = { 0, 0, 0, -1, -1, -1 }; +static int drive2[6] = { 0, 0, 0, -1, -1, -1 }; +static int drive3[6] = { 0, 0, 0, -1, -1, -1 }; + +static int (*drives[4])[6] = {&drive0, &drive1, &drive2, &drive3}; +static int pg_drive_count; + +enum {D_PRT, D_PRO, D_UNI, D_MOD, D_SLV, D_DLY}; + +/* end of parameters */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/fs.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/mtio.h> +#include <linux/pg.h> +#include <linux/device.h> +#include <linux/sched.h> /* current, TASK_* */ +#include <linux/mutex.h> +#include <linux/jiffies.h> + +#include <asm/uaccess.h> + +module_param(verbose, int, 0644); +module_param(major, int, 0); +module_param(name, charp, 0); +module_param_array(drive0, int, NULL, 0); +module_param_array(drive1, int, NULL, 0); +module_param_array(drive2, int, NULL, 0); +module_param_array(drive3, int, NULL, 0); + +#include "paride.h" + +#define PG_SPIN_DEL 50 /* spin delay in micro-seconds */ +#define PG_SPIN 200 +#define PG_TMO HZ +#define PG_RESET_TMO 10*HZ + +#define STAT_ERR 0x01 +#define STAT_INDEX 0x02 +#define STAT_ECC 0x04 +#define STAT_DRQ 0x08 +#define STAT_SEEK 0x10 +#define STAT_WRERR 0x20 +#define STAT_READY 0x40 +#define STAT_BUSY 0x80 + +#define ATAPI_IDENTIFY 0x12 + +static DEFINE_MUTEX(pg_mutex); +static int pg_open(struct inode *inode, struct file *file); +static int pg_release(struct inode *inode, struct file *file); +static ssize_t pg_read(struct file *filp, char __user *buf, + size_t count, loff_t * ppos); +static ssize_t pg_write(struct file *filp, const char __user *buf, + size_t count, loff_t * ppos); +static int pg_detect(void); + +#define PG_NAMELEN 8 + +struct pg { + struct pi_adapter pia; /* interface to paride layer */ + struct pi_adapter *pi; + int busy; /* write done, read expected */ + int start; /* jiffies at command start */ + int dlen; /* transfer size requested */ + unsigned long timeout; /* timeout requested */ + int status; /* last sense key */ + int drive; /* drive */ + unsigned long access; /* count of active opens ... */ + int present; /* device present ? */ + char *bufptr; + char name[PG_NAMELEN]; /* pg0, pg1, ... */ +}; + +static struct pg devices[PG_UNITS]; + +static int pg_identify(struct pg *dev, int log); + +static char pg_scratch[512]; /* scratch block buffer */ + +static struct class *pg_class; + +/* kernel glue structures */ + +static const struct file_operations pg_fops = { + .owner = THIS_MODULE, + .read = pg_read, + .write = pg_write, + .open = pg_open, + .release = pg_release, + .llseek = noop_llseek, +}; + +static void pg_init_units(void) +{ + int unit; + + pg_drive_count = 0; + for (unit = 0; unit < PG_UNITS; unit++) { + int *parm = *drives[unit]; + struct pg *dev = &devices[unit]; + dev->pi = &dev->pia; + clear_bit(0, &dev->access); + dev->busy = 0; + dev->present = 0; + dev->bufptr = NULL; + dev->drive = parm[D_SLV]; + snprintf(dev->name, PG_NAMELEN, "%s%c", name, 'a'+unit); + if (parm[D_PRT]) + pg_drive_count++; + } +} + +static inline int status_reg(struct pg *dev) +{ + return pi_read_regr(dev->pi, 1, 6); +} + +static inline int read_reg(struct pg *dev, int reg) +{ + return pi_read_regr(dev->pi, 0, reg); +} + +static inline void write_reg(struct pg *dev, int reg, int val) +{ + pi_write_regr(dev->pi, 0, reg, val); +} + +static inline u8 DRIVE(struct pg *dev) +{ + return 0xa0+0x10*dev->drive; +} + +static void pg_sleep(int cs) +{ + schedule_timeout_interruptible(cs); +} + +static int pg_wait(struct pg *dev, int go, int stop, unsigned long tmo, char *msg) +{ + int j, r, e, s, p, to; + + dev->status = 0; + + j = 0; + while ((((r = status_reg(dev)) & go) || (stop && (!(r & stop)))) + && time_before(jiffies, tmo)) { + if (j++ < PG_SPIN) + udelay(PG_SPIN_DEL); + else + pg_sleep(1); + } + + to = time_after_eq(jiffies, tmo); + + if ((r & (STAT_ERR & stop)) || to) { + s = read_reg(dev, 7); + e = read_reg(dev, 1); + p = read_reg(dev, 2); + if (verbose > 1) + printk("%s: %s: stat=0x%x err=0x%x phase=%d%s\n", + dev->name, msg, s, e, p, to ? " timeout" : ""); + if (to) + e |= 0x100; + dev->status = (e >> 4) & 0xff; + return -1; + } + return 0; +} + +static int pg_command(struct pg *dev, char *cmd, int dlen, unsigned long tmo) +{ + int k; + + pi_connect(dev->pi); + + write_reg(dev, 6, DRIVE(dev)); + + if (pg_wait(dev, STAT_BUSY | STAT_DRQ, 0, tmo, "before command")) + goto fail; + + write_reg(dev, 4, dlen % 256); + write_reg(dev, 5, dlen / 256); + write_reg(dev, 7, 0xa0); /* ATAPI packet command */ + + if (pg_wait(dev, STAT_BUSY, STAT_DRQ, tmo, "command DRQ")) + goto fail; + + if (read_reg(dev, 2) != 1) { + printk("%s: command phase error\n", dev->name); + goto fail; + } + + pi_write_block(dev->pi, cmd, 12); + + if (verbose > 1) { + printk("%s: Command sent, dlen=%d packet= ", dev->name, dlen); + for (k = 0; k < 12; k++) + printk("%02x ", cmd[k] & 0xff); + printk("\n"); + } + return 0; +fail: + pi_disconnect(dev->pi); + return -1; +} + +static int pg_completion(struct pg *dev, char *buf, unsigned long tmo) +{ + int r, d, n, p; + + r = pg_wait(dev, STAT_BUSY, STAT_DRQ | STAT_READY | STAT_ERR, + tmo, "completion"); + + dev->dlen = 0; + + while (read_reg(dev, 7) & STAT_DRQ) { + d = (read_reg(dev, 4) + 256 * read_reg(dev, 5)); + n = ((d + 3) & 0xfffc); + p = read_reg(dev, 2) & 3; + if (p == 0) + pi_write_block(dev->pi, buf, n); + if (p == 2) + pi_read_block(dev->pi, buf, n); + if (verbose > 1) + printk("%s: %s %d bytes\n", dev->name, + p ? "Read" : "Write", n); + dev->dlen += (1 - p) * d; + buf += d; + r = pg_wait(dev, STAT_BUSY, STAT_DRQ | STAT_READY | STAT_ERR, + tmo, "completion"); + } + + pi_disconnect(dev->pi); + + return r; +} + +static int pg_reset(struct pg *dev) +{ + int i, k, err; + int expect[5] = { 1, 1, 1, 0x14, 0xeb }; + int got[5]; + + pi_connect(dev->pi); + write_reg(dev, 6, DRIVE(dev)); + write_reg(dev, 7, 8); + + pg_sleep(20 * HZ / 1000); + + k = 0; + while ((k++ < PG_RESET_TMO) && (status_reg(dev) & STAT_BUSY)) + pg_sleep(1); + + for (i = 0; i < 5; i++) + got[i] = read_reg(dev, i + 1); + + err = memcmp(expect, got, sizeof(got)) ? -1 : 0; + + if (verbose) { + printk("%s: Reset (%d) signature = ", dev->name, k); + for (i = 0; i < 5; i++) + printk("%3x", got[i]); + if (err) + printk(" (incorrect)"); + printk("\n"); + } + + pi_disconnect(dev->pi); + return err; +} + +static void xs(char *buf, char *targ, int len) +{ + char l = '\0'; + int k; + + for (k = 0; k < len; k++) { + char c = *buf++; + if (c != ' ' && c != l) + l = *targ++ = c; + } + if (l == ' ') + targ--; + *targ = '\0'; +} + +static int pg_identify(struct pg *dev, int log) +{ + int s; + char *ms[2] = { "master", "slave" }; + char mf[10], id[18]; + char id_cmd[12] = { ATAPI_IDENTIFY, 0, 0, 0, 36, 0, 0, 0, 0, 0, 0, 0 }; + char buf[36]; + + s = pg_command(dev, id_cmd, 36, jiffies + PG_TMO); + if (s) + return -1; + s = pg_completion(dev, buf, jiffies + PG_TMO); + if (s) + return -1; + + if (log) { + xs(buf + 8, mf, 8); + xs(buf + 16, id, 16); + printk("%s: %s %s, %s\n", dev->name, mf, id, ms[dev->drive]); + } + + return 0; +} + +/* + * returns 0, with id set if drive is detected + * -1, if drive detection failed + */ +static int pg_probe(struct pg *dev) +{ + if (dev->drive == -1) { + for (dev->drive = 0; dev->drive <= 1; dev->drive++) + if (!pg_reset(dev)) + return pg_identify(dev, 1); + } else { + if (!pg_reset(dev)) + return pg_identify(dev, 1); + } + return -1; +} + +static int pg_detect(void) +{ + struct pg *dev = &devices[0]; + int k, unit; + + printk("%s: %s version %s, major %d\n", name, name, PG_VERSION, major); + + k = 0; + if (pg_drive_count == 0) { + if (pi_init(dev->pi, 1, -1, -1, -1, -1, -1, pg_scratch, + PI_PG, verbose, dev->name)) { + if (!pg_probe(dev)) { + dev->present = 1; + k++; + } else + pi_release(dev->pi); + } + + } else + for (unit = 0; unit < PG_UNITS; unit++, dev++) { + int *parm = *drives[unit]; + if (!parm[D_PRT]) + continue; + if (pi_init(dev->pi, 0, parm[D_PRT], parm[D_MOD], + parm[D_UNI], parm[D_PRO], parm[D_DLY], + pg_scratch, PI_PG, verbose, dev->name)) { + if (!pg_probe(dev)) { + dev->present = 1; + k++; + } else + pi_release(dev->pi); + } + } + + if (k) + return 0; + + printk("%s: No ATAPI device detected\n", name); + return -1; +} + +static int pg_open(struct inode *inode, struct file *file) +{ + int unit = iminor(inode) & 0x7f; + struct pg *dev = &devices[unit]; + int ret = 0; + + mutex_lock(&pg_mutex); + if ((unit >= PG_UNITS) || (!dev->present)) { + ret = -ENODEV; + goto out; + } + + if (test_and_set_bit(0, &dev->access)) { + ret = -EBUSY; + goto out; + } + + if (dev->busy) { + pg_reset(dev); + dev->busy = 0; + } + + pg_identify(dev, (verbose > 1)); + + dev->bufptr = kmalloc(PG_MAX_DATA, GFP_KERNEL); + if (dev->bufptr == NULL) { + clear_bit(0, &dev->access); + printk("%s: buffer allocation failed\n", dev->name); + ret = -ENOMEM; + goto out; + } + + file->private_data = dev; + +out: + mutex_unlock(&pg_mutex); + return ret; +} + +static int pg_release(struct inode *inode, struct file *file) +{ + struct pg *dev = file->private_data; + + kfree(dev->bufptr); + dev->bufptr = NULL; + clear_bit(0, &dev->access); + + return 0; +} + +static ssize_t pg_write(struct file *filp, const char __user *buf, size_t count, loff_t *ppos) +{ + struct pg *dev = filp->private_data; + struct pg_write_hdr hdr; + int hs = sizeof (hdr); + + if (dev->busy) + return -EBUSY; + if (count < hs) + return -EINVAL; + + if (copy_from_user(&hdr, buf, hs)) + return -EFAULT; + + if (hdr.magic != PG_MAGIC) + return -EINVAL; + if (hdr.dlen < 0 || hdr.dlen > PG_MAX_DATA) + return -EINVAL; + if ((count - hs) > PG_MAX_DATA) + return -EINVAL; + + if (hdr.func == PG_RESET) { + if (count != hs) + return -EINVAL; + if (pg_reset(dev)) + return -EIO; + return count; + } + + if (hdr.func != PG_COMMAND) + return -EINVAL; + + dev->start = jiffies; + dev->timeout = hdr.timeout * HZ + HZ / 2 + jiffies; + + if (pg_command(dev, hdr.packet, hdr.dlen, jiffies + PG_TMO)) { + if (dev->status & 0x10) + return -ETIME; + return -EIO; + } + + dev->busy = 1; + + if (copy_from_user(dev->bufptr, buf + hs, count - hs)) + return -EFAULT; + return count; +} + +static ssize_t pg_read(struct file *filp, char __user *buf, size_t count, loff_t *ppos) +{ + struct pg *dev = filp->private_data; + struct pg_read_hdr hdr; + int hs = sizeof (hdr); + int copy; + + if (!dev->busy) + return -EINVAL; + if (count < hs) + return -EINVAL; + + dev->busy = 0; + + if (pg_completion(dev, dev->bufptr, dev->timeout)) + if (dev->status & 0x10) + return -ETIME; + + memset(&hdr, 0, sizeof(hdr)); + hdr.magic = PG_MAGIC; + hdr.dlen = dev->dlen; + copy = 0; + + if (hdr.dlen < 0) { + hdr.dlen = -1 * hdr.dlen; + copy = hdr.dlen; + if (copy > (count - hs)) + copy = count - hs; + } + + hdr.duration = (jiffies - dev->start + HZ / 2) / HZ; + hdr.scsi = dev->status & 0x0f; + + if (copy_to_user(buf, &hdr, hs)) + return -EFAULT; + if (copy > 0) + if (copy_to_user(buf + hs, dev->bufptr, copy)) + return -EFAULT; + return copy + hs; +} + +static int __init pg_init(void) +{ + int unit; + int err; + + if (disable){ + err = -EINVAL; + goto out; + } + + pg_init_units(); + + if (pg_detect()) { + err = -ENODEV; + goto out; + } + + err = register_chrdev(major, name, &pg_fops); + if (err < 0) { + printk("pg_init: unable to get major number %d\n", major); + for (unit = 0; unit < PG_UNITS; unit++) { + struct pg *dev = &devices[unit]; + if (dev->present) + pi_release(dev->pi); + } + goto out; + } + major = err; /* In case the user specified `major=0' (dynamic) */ + pg_class = class_create(THIS_MODULE, "pg"); + if (IS_ERR(pg_class)) { + err = PTR_ERR(pg_class); + goto out_chrdev; + } + for (unit = 0; unit < PG_UNITS; unit++) { + struct pg *dev = &devices[unit]; + if (dev->present) + device_create(pg_class, NULL, MKDEV(major, unit), NULL, + "pg%u", unit); + } + err = 0; + goto out; + +out_chrdev: + unregister_chrdev(major, "pg"); +out: + return err; +} + +static void __exit pg_exit(void) +{ + int unit; + + for (unit = 0; unit < PG_UNITS; unit++) { + struct pg *dev = &devices[unit]; + if (dev->present) + device_destroy(pg_class, MKDEV(major, unit)); + } + class_destroy(pg_class); + unregister_chrdev(major, name); + + for (unit = 0; unit < PG_UNITS; unit++) { + struct pg *dev = &devices[unit]; + if (dev->present) + pi_release(dev->pi); + } +} + +MODULE_LICENSE("GPL"); +module_init(pg_init) +module_exit(pg_exit) |