2 pg.c (c) 1998 Grant R. Guenther <grant@torque.net>
3 Under the terms of the GNU General Public License.
5 The pg driver provides a simple character device interface for
6 sending ATAPI commands to a device. With the exception of the
7 ATAPI reset operation, all operations are performed by a pair
8 of read and write operations to the appropriate /dev/pgN device.
9 A write operation delivers a command and any outbound data in
10 a single buffer. Normally, the write will succeed unless the
11 device is offline or malfunctioning, or there is already another
12 command pending. If the write succeeds, it should be followed
13 immediately by a read operation, to obtain any returned data and
14 status information. A read will fail if there is no operation
17 As a special case, the device can be reset with a write operation,
18 and in this case, no following read is expected, or permitted.
20 There are no ioctl() operations. Any single operation
21 may transfer at most PG_MAX_DATA bytes. Note that the driver must
22 copy the data through an internal buffer. In keeping with all
23 current ATAPI devices, command packets are assumed to be exactly
26 To permit future changes to this interface, the headers in the
27 read and write buffers contain a single character "magic" flag.
28 Currently this flag must be the character "P".
30 By default, the driver will autoprobe for a single parallel
31 port ATAPI device, but if their individual parameters are
32 specified, the driver can handle up to 4 devices.
34 To use this device, you must have the following device
35 special files defined:
42 (You'll need to change the 97 to something else if you use
43 the 'major' parameter to install the driver on a different
46 The behaviour of the pg driver can be altered by setting
47 some parameters from the insmod command line. The following
48 parameters are adjustable:
50 drive0 These four arguments can be arrays of
51 drive1 1-6 integers as follows:
53 drive3 <prt>,<pro>,<uni>,<mod>,<slv>,<dly>
57 <prt> is the base of the parallel port address for
58 the corresponding drive. (required)
60 <pro> is the protocol number for the adapter that
61 supports this drive. These numbers are
62 logged by 'paride' when the protocol modules
63 are initialised. (0 if not given)
65 <uni> for those adapters that support chained
66 devices, this is the unit selector for the
67 chain of devices on the given port. It should
68 be zero for devices that don't support chaining.
71 <mod> this can be -1 to choose the best mode, or one
72 of the mode numbers supported by the adapter.
75 <slv> ATAPI devices can be jumpered to master or slave.
76 Set this to 0 to choose the master drive, 1 to
77 choose the slave, -1 (the default) to choose the
80 <dly> some parallel ports require the driver to
81 go more slowly. -1 sets a default value that
82 should work with the chosen protocol. Otherwise,
83 set this to a small integer, the larger it is
84 the slower the port i/o. In some cases, setting
85 this to zero will speed up the device. (default -1)
87 major You may use this parameter to overide the
88 default major number (97) that this driver
89 will use. Be sure to change the device
92 name This parameter is a character string that
93 contains the name the kernel will use for this
94 device (in /proc output, for instance).
97 verbose This parameter controls the amount of logging
98 that is done by the driver. Set it to 0 for
99 quiet operation, to 1 to enable progress
100 messages while the driver probes for devices,
101 or to 2 for full debug logging. (default 0)
103 If this driver is built into the kernel, you can use
104 the following command line parameters, with the same values
105 as the corresponding module parameters listed above:
112 In addition, you can use the parameter pg.disable to disable
119 1.01 GRG 1998.06.16 Bug fixes
120 1.02 GRG 1998.09.24 Added jumbo support
124 #define PG_VERSION "1.02"
133 /* Here are things one can override from the insmod command.
134 Most are autoprobed by paride unless set here. Verbose is 0
139 static int verbose
= 0;
140 static int major
= PG_MAJOR
;
141 static char *name
= PG_NAME
;
142 static int disable
= 0;
144 static int drive0
[6] = { 0, 0, 0, -1, -1, -1 };
145 static int drive1
[6] = { 0, 0, 0, -1, -1, -1 };
146 static int drive2
[6] = { 0, 0, 0, -1, -1, -1 };
147 static int drive3
[6] = { 0, 0, 0, -1, -1, -1 };
149 static int (*drives
[4])[6] = {&drive0
, &drive1
, &drive2
, &drive3
};
150 static int pg_drive_count
;
152 enum {D_PRT
, D_PRO
, D_UNI
, D_MOD
, D_SLV
, D_DLY
};
154 /* end of parameters */
156 #include <linux/module.h>
157 #include <linux/init.h>
158 #include <linux/fs.h>
159 #include <linux/devfs_fs_kernel.h>
160 #include <linux/delay.h>
161 #include <linux/slab.h>
162 #include <linux/mtio.h>
163 #include <linux/pg.h>
164 #include <linux/device.h>
166 #include <asm/uaccess.h>
168 module_param(verbose
, bool, 0644);
169 module_param(major
, int, 0);
170 module_param(name
, charp
, 0);
171 module_param_array(drive0
, int, NULL
, 0);
172 module_param_array(drive1
, int, NULL
, 0);
173 module_param_array(drive2
, int, NULL
, 0);
174 module_param_array(drive3
, int, NULL
, 0);
178 #define PG_SPIN_DEL 50 /* spin delay in micro-seconds */
181 #define PG_RESET_TMO 10*HZ
183 #define STAT_ERR 0x01
184 #define STAT_INDEX 0x02
185 #define STAT_ECC 0x04
186 #define STAT_DRQ 0x08
187 #define STAT_SEEK 0x10
188 #define STAT_WRERR 0x20
189 #define STAT_READY 0x40
190 #define STAT_BUSY 0x80
192 #define ATAPI_IDENTIFY 0x12
194 static int pg_open(struct inode
*inode
, struct file
*file
);
195 static int pg_release(struct inode
*inode
, struct file
*file
);
196 static ssize_t
pg_read(struct file
*filp
, char __user
*buf
,
197 size_t count
, loff_t
* ppos
);
198 static ssize_t
pg_write(struct file
*filp
, const char __user
*buf
,
199 size_t count
, loff_t
* ppos
);
200 static int pg_detect(void);
205 struct pi_adapter pia
; /* interface to paride layer */
206 struct pi_adapter
*pi
;
207 int busy
; /* write done, read expected */
208 int start
; /* jiffies at command start */
209 int dlen
; /* transfer size requested */
210 unsigned long timeout
; /* timeout requested */
211 int status
; /* last sense key */
212 int drive
; /* drive */
213 unsigned long access
; /* count of active opens ... */
214 int present
; /* device present ? */
216 char name
[PG_NAMELEN
]; /* pg0, pg1, ... */
219 static struct pg devices
[PG_UNITS
];
221 static int pg_identify(struct pg
*dev
, int log
);
223 static char pg_scratch
[512]; /* scratch block buffer */
225 static struct class *pg_class
;
227 /* kernel glue structures */
229 static struct file_operations pg_fops
= {
230 .owner
= THIS_MODULE
,
234 .release
= pg_release
,
237 static void pg_init_units(void)
242 for (unit
= 0; unit
< PG_UNITS
; unit
++) {
243 int *parm
= *drives
[unit
];
244 struct pg
*dev
= &devices
[unit
];
246 clear_bit(0, &dev
->access
);
250 dev
->drive
= parm
[D_SLV
];
251 snprintf(dev
->name
, PG_NAMELEN
, "%s%c", name
, 'a'+unit
);
257 static inline int status_reg(struct pg
*dev
)
259 return pi_read_regr(dev
->pi
, 1, 6);
262 static inline int read_reg(struct pg
*dev
, int reg
)
264 return pi_read_regr(dev
->pi
, 0, reg
);
267 static inline void write_reg(struct pg
*dev
, int reg
, int val
)
269 pi_write_regr(dev
->pi
, 0, reg
, val
);
272 static inline u8
DRIVE(struct pg
*dev
)
274 return 0xa0+0x10*dev
->drive
;
277 static void pg_sleep(int cs
)
279 current
->state
= TASK_INTERRUPTIBLE
;
280 schedule_timeout(cs
);
283 static int pg_wait(struct pg
*dev
, int go
, int stop
, unsigned long tmo
, char *msg
)
285 int j
, r
, e
, s
, p
, to
;
290 while ((((r
= status_reg(dev
)) & go
) || (stop
&& (!(r
& stop
))))
291 && time_before(jiffies
, tmo
)) {
298 to
= time_after_eq(jiffies
, tmo
);
300 if ((r
& (STAT_ERR
& stop
)) || to
) {
301 s
= read_reg(dev
, 7);
302 e
= read_reg(dev
, 1);
303 p
= read_reg(dev
, 2);
305 printk("%s: %s: stat=0x%x err=0x%x phase=%d%s\n",
306 dev
->name
, msg
, s
, e
, p
, to
? " timeout" : "");
309 dev
->status
= (e
>> 4) & 0xff;
315 static int pg_command(struct pg
*dev
, char *cmd
, int dlen
, unsigned long tmo
)
321 write_reg(dev
, 6, DRIVE(dev
));
323 if (pg_wait(dev
, STAT_BUSY
| STAT_DRQ
, 0, tmo
, "before command"))
326 write_reg(dev
, 4, dlen
% 256);
327 write_reg(dev
, 5, dlen
/ 256);
328 write_reg(dev
, 7, 0xa0); /* ATAPI packet command */
330 if (pg_wait(dev
, STAT_BUSY
, STAT_DRQ
, tmo
, "command DRQ"))
333 if (read_reg(dev
, 2) != 1) {
334 printk("%s: command phase error\n", dev
->name
);
338 pi_write_block(dev
->pi
, cmd
, 12);
341 printk("%s: Command sent, dlen=%d packet= ", dev
->name
, dlen
);
342 for (k
= 0; k
< 12; k
++)
343 printk("%02x ", cmd
[k
] & 0xff);
348 pi_disconnect(dev
->pi
);
352 static int pg_completion(struct pg
*dev
, char *buf
, unsigned long tmo
)
356 r
= pg_wait(dev
, STAT_BUSY
, STAT_DRQ
| STAT_READY
| STAT_ERR
,
361 while (read_reg(dev
, 7) & STAT_DRQ
) {
362 d
= (read_reg(dev
, 4) + 256 * read_reg(dev
, 5));
363 n
= ((d
+ 3) & 0xfffc);
364 p
= read_reg(dev
, 2) & 3;
366 pi_write_block(dev
->pi
, buf
, n
);
368 pi_read_block(dev
->pi
, buf
, n
);
370 printk("%s: %s %d bytes\n", dev
->name
,
371 p
? "Read" : "Write", n
);
372 dev
->dlen
+= (1 - p
) * d
;
374 r
= pg_wait(dev
, STAT_BUSY
, STAT_DRQ
| STAT_READY
| STAT_ERR
,
378 pi_disconnect(dev
->pi
);
383 static int pg_reset(struct pg
*dev
)
386 int expect
[5] = { 1, 1, 1, 0x14, 0xeb };
390 write_reg(dev
, 6, DRIVE(dev
));
391 write_reg(dev
, 7, 8);
393 pg_sleep(20 * HZ
/ 1000);
396 while ((k
++ < PG_RESET_TMO
) && (status_reg(dev
) & STAT_BUSY
))
399 for (i
= 0; i
< 5; i
++)
400 got
[i
] = read_reg(dev
, i
+ 1);
402 err
= memcmp(expect
, got
, sizeof(got
)) ? -1 : 0;
405 printk("%s: Reset (%d) signature = ", dev
->name
, k
);
406 for (i
= 0; i
< 5; i
++)
407 printk("%3x", got
[i
]);
409 printk(" (incorrect)");
413 pi_disconnect(dev
->pi
);
417 static void xs(char *buf
, char *targ
, int len
)
422 for (k
= 0; k
< len
; k
++) {
424 if (c
!= ' ' || c
!= l
)
432 static int pg_identify(struct pg
*dev
, int log
)
435 char *ms
[2] = { "master", "slave" };
437 char id_cmd
[12] = { ATAPI_IDENTIFY
, 0, 0, 0, 36, 0, 0, 0, 0, 0, 0, 0 };
440 s
= pg_command(dev
, id_cmd
, 36, jiffies
+ PG_TMO
);
443 s
= pg_completion(dev
, buf
, jiffies
+ PG_TMO
);
449 xs(buf
+ 16, id
, 16);
450 printk("%s: %s %s, %s\n", dev
->name
, mf
, id
, ms
[dev
->drive
]);
457 * returns 0, with id set if drive is detected
458 * -1, if drive detection failed
460 static int pg_probe(struct pg
*dev
)
462 if (dev
->drive
== -1) {
463 for (dev
->drive
= 0; dev
->drive
<= 1; dev
->drive
++)
465 return pg_identify(dev
, 1);
468 return pg_identify(dev
, 1);
473 static int pg_detect(void)
475 struct pg
*dev
= &devices
[0];
478 printk("%s: %s version %s, major %d\n", name
, name
, PG_VERSION
, major
);
481 if (pg_drive_count
== 0) {
482 if (pi_init(dev
->pi
, 1, -1, -1, -1, -1, -1, pg_scratch
,
483 PI_PG
, verbose
, dev
->name
)) {
484 if (!pg_probe(dev
)) {
492 for (unit
= 0; unit
< PG_UNITS
; unit
++, dev
++) {
493 int *parm
= *drives
[unit
];
496 if (pi_init(dev
->pi
, 0, parm
[D_PRT
], parm
[D_MOD
],
497 parm
[D_UNI
], parm
[D_PRO
], parm
[D_DLY
],
498 pg_scratch
, PI_PG
, verbose
, dev
->name
)) {
499 if (!pg_probe(dev
)) {
510 printk("%s: No ATAPI device detected\n", name
);
514 static int pg_open(struct inode
*inode
, struct file
*file
)
516 int unit
= iminor(inode
) & 0x7f;
517 struct pg
*dev
= &devices
[unit
];
519 if ((unit
>= PG_UNITS
) || (!dev
->present
))
522 if (test_and_set_bit(0, &dev
->access
))
530 pg_identify(dev
, (verbose
> 1));
532 dev
->bufptr
= kmalloc(PG_MAX_DATA
, GFP_KERNEL
);
533 if (dev
->bufptr
== NULL
) {
534 clear_bit(0, &dev
->access
);
535 printk("%s: buffer allocation failed\n", dev
->name
);
539 file
->private_data
= dev
;
544 static int pg_release(struct inode
*inode
, struct file
*file
)
546 struct pg
*dev
= file
->private_data
;
550 clear_bit(0, &dev
->access
);
555 static ssize_t
pg_write(struct file
*filp
, const char __user
*buf
, size_t count
, loff_t
*ppos
)
557 struct pg
*dev
= filp
->private_data
;
558 struct pg_write_hdr hdr
;
559 int hs
= sizeof (hdr
);
566 if (copy_from_user(&hdr
, buf
, hs
))
569 if (hdr
.magic
!= PG_MAGIC
)
571 if (hdr
.dlen
> PG_MAX_DATA
)
573 if ((count
- hs
) > PG_MAX_DATA
)
576 if (hdr
.func
== PG_RESET
) {
584 if (hdr
.func
!= PG_COMMAND
)
587 dev
->start
= jiffies
;
588 dev
->timeout
= hdr
.timeout
* HZ
+ HZ
/ 2 + jiffies
;
590 if (pg_command(dev
, hdr
.packet
, hdr
.dlen
, jiffies
+ PG_TMO
)) {
591 if (dev
->status
& 0x10)
598 if (copy_from_user(dev
->bufptr
, buf
+ hs
, count
- hs
))
603 static ssize_t
pg_read(struct file
*filp
, char __user
*buf
, size_t count
, loff_t
*ppos
)
605 struct pg
*dev
= filp
->private_data
;
606 struct pg_read_hdr hdr
;
607 int hs
= sizeof (hdr
);
617 if (pg_completion(dev
, dev
->bufptr
, dev
->timeout
))
618 if (dev
->status
& 0x10)
621 hdr
.magic
= PG_MAGIC
;
622 hdr
.dlen
= dev
->dlen
;
626 hdr
.dlen
= -1 * hdr
.dlen
;
628 if (copy
> (count
- hs
))
632 hdr
.duration
= (jiffies
- dev
->start
+ HZ
/ 2) / HZ
;
633 hdr
.scsi
= dev
->status
& 0x0f;
635 if (copy_to_user(buf
, &hdr
, hs
))
638 if (copy_to_user(buf
+ hs
, dev
->bufptr
, copy
))
643 static int __init
pg_init(void)
659 if (register_chrdev(major
, name
, &pg_fops
)) {
660 printk("pg_init: unable to get major number %d\n", major
);
661 for (unit
= 0; unit
< PG_UNITS
; unit
++) {
662 struct pg
*dev
= &devices
[unit
];
669 pg_class
= class_create(THIS_MODULE
, "pg");
670 if (IS_ERR(pg_class
)) {
671 err
= PTR_ERR(pg_class
);
675 for (unit
= 0; unit
< PG_UNITS
; unit
++) {
676 struct pg
*dev
= &devices
[unit
];
678 class_device_create(pg_class
, MKDEV(major
, unit
),
680 err
= devfs_mk_cdev(MKDEV(major
, unit
),
681 S_IFCHR
| S_IRUSR
| S_IWUSR
, "pg/%u",
691 class_device_destroy(pg_class
, MKDEV(major
, unit
));
692 class_destroy(pg_class
);
694 unregister_chrdev(major
, "pg");
699 static void __exit
pg_exit(void)
703 for (unit
= 0; unit
< PG_UNITS
; unit
++) {
704 struct pg
*dev
= &devices
[unit
];
706 class_device_destroy(pg_class
, MKDEV(major
, unit
));
707 devfs_remove("pg/%u", unit
);
710 class_destroy(pg_class
);
712 unregister_chrdev(major
, name
);
714 for (unit
= 0; unit
< PG_UNITS
; unit
++) {
715 struct pg
*dev
= &devices
[unit
];
721 MODULE_LICENSE("GPL");
This page took 0.044374 seconds and 6 git commands to generate.