Merge branch 'topic/docbook-fix' into for-linus
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / sbus / char / openprom.c
1 /*
2 * Linux/SPARC PROM Configuration Driver
3 * Copyright (C) 1996 Thomas K. Dyas (tdyas@noc.rutgers.edu)
4 * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be)
5 *
6 * This character device driver allows user programs to access the
7 * PROM device tree. It is compatible with the SunOS /dev/openprom
8 * driver and the NetBSD /dev/openprom driver. The SunOS eeprom
9 * utility works without any modifications.
10 *
11 * The driver uses a minor number under the misc device major. The
12 * file read/write mode determines the type of access to the PROM.
13 * Interrupts are disabled whenever the driver calls into the PROM for
14 * sanity's sake.
15 */
16
17 /* This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License as
19 * published by the Free Software Foundation; either version 2 of the
20 * License, or (at your option) any later version.
21 *
22 * This program is distributed in the hope that it will be useful, but
23 * WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
25 * General Public License for more details.
26 *
27 * You should have received a copy of the GNU General Public License
28 * along with this program; if not, write to the Free Software
29 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
30 */
31
32 #include <linux/module.h>
33 #include <linux/kernel.h>
34 #include <linux/errno.h>
35 #include <linux/slab.h>
36 #include <linux/smp_lock.h>
37 #include <linux/string.h>
38 #include <linux/miscdevice.h>
39 #include <linux/init.h>
40 #include <linux/fs.h>
41 #include <asm/oplib.h>
42 #include <asm/prom.h>
43 #include <asm/system.h>
44 #include <asm/uaccess.h>
45 #include <asm/openpromio.h>
46 #ifdef CONFIG_PCI
47 #include <linux/pci.h>
48 #endif
49
50 MODULE_AUTHOR("Thomas K. Dyas (tdyas@noc.rutgers.edu) and Eddie C. Dost (ecd@skynet.be)");
51 MODULE_DESCRIPTION("OPENPROM Configuration Driver");
52 MODULE_LICENSE("GPL");
53 MODULE_VERSION("1.0");
54 MODULE_ALIAS_MISCDEV(SUN_OPENPROM_MINOR);
55
56 /* Private data kept by the driver for each descriptor. */
57 typedef struct openprom_private_data
58 {
59 struct device_node *current_node; /* Current node for SunOS ioctls. */
60 struct device_node *lastnode; /* Last valid node used by BSD ioctls. */
61 } DATA;
62
63 /* ID of the PROM node containing all of the EEPROM options. */
64 static struct device_node *options_node;
65
66 /*
67 * Copy an openpromio structure into kernel space from user space.
68 * This routine does error checking to make sure that all memory
69 * accesses are within bounds. A pointer to the allocated openpromio
70 * structure will be placed in "*opp_p". Return value is the length
71 * of the user supplied buffer.
72 */
73 static int copyin(struct openpromio __user *info, struct openpromio **opp_p)
74 {
75 unsigned int bufsize;
76
77 if (!info || !opp_p)
78 return -EFAULT;
79
80 if (get_user(bufsize, &info->oprom_size))
81 return -EFAULT;
82
83 if (bufsize == 0)
84 return -EINVAL;
85
86 /* If the bufsize is too large, just limit it.
87 * Fix from Jason Rappleye.
88 */
89 if (bufsize > OPROMMAXPARAM)
90 bufsize = OPROMMAXPARAM;
91
92 if (!(*opp_p = kzalloc(sizeof(int) + bufsize + 1, GFP_KERNEL)))
93 return -ENOMEM;
94
95 if (copy_from_user(&(*opp_p)->oprom_array,
96 &info->oprom_array, bufsize)) {
97 kfree(*opp_p);
98 return -EFAULT;
99 }
100 return bufsize;
101 }
102
103 static int getstrings(struct openpromio __user *info, struct openpromio **opp_p)
104 {
105 int n, bufsize;
106 char c;
107
108 if (!info || !opp_p)
109 return -EFAULT;
110
111 if (!(*opp_p = kzalloc(sizeof(int) + OPROMMAXPARAM + 1, GFP_KERNEL)))
112 return -ENOMEM;
113
114 (*opp_p)->oprom_size = 0;
115
116 n = bufsize = 0;
117 while ((n < 2) && (bufsize < OPROMMAXPARAM)) {
118 if (get_user(c, &info->oprom_array[bufsize])) {
119 kfree(*opp_p);
120 return -EFAULT;
121 }
122 if (c == '\0')
123 n++;
124 (*opp_p)->oprom_array[bufsize++] = c;
125 }
126 if (!n) {
127 kfree(*opp_p);
128 return -EINVAL;
129 }
130 return bufsize;
131 }
132
133 /*
134 * Copy an openpromio structure in kernel space back to user space.
135 */
136 static int copyout(void __user *info, struct openpromio *opp, int len)
137 {
138 if (copy_to_user(info, opp, len))
139 return -EFAULT;
140 return 0;
141 }
142
143 static int opromgetprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
144 {
145 const void *pval;
146 int len;
147
148 if (!dp ||
149 !(pval = of_get_property(dp, op->oprom_array, &len)) ||
150 len <= 0 || len > bufsize)
151 return copyout(argp, op, sizeof(int));
152
153 memcpy(op->oprom_array, pval, len);
154 op->oprom_array[len] = '\0';
155 op->oprom_size = len;
156
157 return copyout(argp, op, sizeof(int) + bufsize);
158 }
159
160 static int opromnxtprop(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize)
161 {
162 struct property *prop;
163 int len;
164
165 if (!dp)
166 return copyout(argp, op, sizeof(int));
167 if (op->oprom_array[0] == '\0') {
168 prop = dp->properties;
169 if (!prop)
170 return copyout(argp, op, sizeof(int));
171 len = strlen(prop->name);
172 } else {
173 prop = of_find_property(dp, op->oprom_array, NULL);
174
175 if (!prop ||
176 !prop->next ||
177 (len = strlen(prop->next->name)) + 1 > bufsize)
178 return copyout(argp, op, sizeof(int));
179
180 prop = prop->next;
181 }
182
183 memcpy(op->oprom_array, prop->name, len);
184 op->oprom_array[len] = '\0';
185 op->oprom_size = ++len;
186
187 return copyout(argp, op, sizeof(int) + bufsize);
188 }
189
190 static int opromsetopt(struct device_node *dp, struct openpromio *op, int bufsize)
191 {
192 char *buf = op->oprom_array + strlen(op->oprom_array) + 1;
193 int len = op->oprom_array + bufsize - buf;
194
195 return of_set_property(options_node, op->oprom_array, buf, len);
196 }
197
198 static int opromnext(void __user *argp, unsigned int cmd, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
199 {
200 phandle ph;
201
202 BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
203
204 if (bufsize < sizeof(phandle))
205 return -EINVAL;
206
207 ph = *((int *) op->oprom_array);
208 if (ph) {
209 dp = of_find_node_by_phandle(ph);
210 if (!dp)
211 return -EINVAL;
212
213 switch (cmd) {
214 case OPROMNEXT:
215 dp = dp->sibling;
216 break;
217
218 case OPROMCHILD:
219 dp = dp->child;
220 break;
221
222 case OPROMSETCUR:
223 default:
224 break;
225 };
226 } else {
227 /* Sibling of node zero is the root node. */
228 if (cmd != OPROMNEXT)
229 return -EINVAL;
230
231 dp = of_find_node_by_path("/");
232 }
233
234 ph = 0;
235 if (dp)
236 ph = dp->node;
237
238 data->current_node = dp;
239 *((int *) op->oprom_array) = ph;
240 op->oprom_size = sizeof(phandle);
241
242 return copyout(argp, op, bufsize + sizeof(int));
243 }
244
245 static int oprompci2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
246 {
247 int err = -EINVAL;
248
249 if (bufsize >= 2*sizeof(int)) {
250 #ifdef CONFIG_PCI
251 struct pci_dev *pdev;
252 struct device_node *dp;
253
254 pdev = pci_get_bus_and_slot (((int *) op->oprom_array)[0],
255 ((int *) op->oprom_array)[1]);
256
257 dp = pci_device_to_OF_node(pdev);
258 data->current_node = dp;
259 *((int *)op->oprom_array) = dp->node;
260 op->oprom_size = sizeof(int);
261 err = copyout(argp, op, bufsize + sizeof(int));
262
263 pci_dev_put(pdev);
264 #endif
265 }
266
267 return err;
268 }
269
270 static int oprompath2node(void __user *argp, struct device_node *dp, struct openpromio *op, int bufsize, DATA *data)
271 {
272 phandle ph = 0;
273
274 dp = of_find_node_by_path(op->oprom_array);
275 if (dp)
276 ph = dp->node;
277 data->current_node = dp;
278 *((int *)op->oprom_array) = ph;
279 op->oprom_size = sizeof(int);
280
281 return copyout(argp, op, bufsize + sizeof(int));
282 }
283
284 static int opromgetbootargs(void __user *argp, struct openpromio *op, int bufsize)
285 {
286 char *buf = saved_command_line;
287 int len = strlen(buf);
288
289 if (len > bufsize)
290 return -EINVAL;
291
292 strcpy(op->oprom_array, buf);
293 op->oprom_size = len;
294
295 return copyout(argp, op, bufsize + sizeof(int));
296 }
297
298 /*
299 * SunOS and Solaris /dev/openprom ioctl calls.
300 */
301 static int openprom_sunos_ioctl(struct inode * inode, struct file * file,
302 unsigned int cmd, unsigned long arg,
303 struct device_node *dp)
304 {
305 DATA *data = file->private_data;
306 struct openpromio *opp;
307 int bufsize, error = 0;
308 static int cnt;
309 void __user *argp = (void __user *)arg;
310
311 if (cmd == OPROMSETOPT)
312 bufsize = getstrings(argp, &opp);
313 else
314 bufsize = copyin(argp, &opp);
315
316 if (bufsize < 0)
317 return bufsize;
318
319 switch (cmd) {
320 case OPROMGETOPT:
321 case OPROMGETPROP:
322 error = opromgetprop(argp, dp, opp, bufsize);
323 break;
324
325 case OPROMNXTOPT:
326 case OPROMNXTPROP:
327 error = opromnxtprop(argp, dp, opp, bufsize);
328 break;
329
330 case OPROMSETOPT:
331 case OPROMSETOPT2:
332 error = opromsetopt(dp, opp, bufsize);
333 break;
334
335 case OPROMNEXT:
336 case OPROMCHILD:
337 case OPROMSETCUR:
338 error = opromnext(argp, cmd, dp, opp, bufsize, data);
339 break;
340
341 case OPROMPCI2NODE:
342 error = oprompci2node(argp, dp, opp, bufsize, data);
343 break;
344
345 case OPROMPATH2NODE:
346 error = oprompath2node(argp, dp, opp, bufsize, data);
347 break;
348
349 case OPROMGETBOOTARGS:
350 error = opromgetbootargs(argp, opp, bufsize);
351 break;
352
353 case OPROMU2P:
354 case OPROMGETCONS:
355 case OPROMGETFBNAME:
356 if (cnt++ < 10)
357 printk(KERN_INFO "openprom_sunos_ioctl: unimplemented ioctl\n");
358 error = -EINVAL;
359 break;
360 default:
361 if (cnt++ < 10)
362 printk(KERN_INFO "openprom_sunos_ioctl: cmd 0x%X, arg 0x%lX\n", cmd, arg);
363 error = -EINVAL;
364 break;
365 }
366
367 kfree(opp);
368 return error;
369 }
370
371 static struct device_node *get_node(phandle n, DATA *data)
372 {
373 struct device_node *dp = of_find_node_by_phandle(n);
374
375 if (dp)
376 data->lastnode = dp;
377
378 return dp;
379 }
380
381 /* Copy in a whole string from userspace into kernelspace. */
382 static int copyin_string(char __user *user, size_t len, char **ptr)
383 {
384 char *tmp;
385
386 if ((ssize_t)len < 0 || (ssize_t)(len + 1) < 0)
387 return -EINVAL;
388
389 tmp = kmalloc(len + 1, GFP_KERNEL);
390 if (!tmp)
391 return -ENOMEM;
392
393 if (copy_from_user(tmp, user, len)) {
394 kfree(tmp);
395 return -EFAULT;
396 }
397
398 tmp[len] = '\0';
399
400 *ptr = tmp;
401
402 return 0;
403 }
404
405 /*
406 * NetBSD /dev/openprom ioctl calls.
407 */
408 static int opiocget(void __user *argp, DATA *data)
409 {
410 struct opiocdesc op;
411 struct device_node *dp;
412 char *str;
413 const void *pval;
414 int err, len;
415
416 if (copy_from_user(&op, argp, sizeof(op)))
417 return -EFAULT;
418
419 dp = get_node(op.op_nodeid, data);
420
421 err = copyin_string(op.op_name, op.op_namelen, &str);
422 if (err)
423 return err;
424
425 pval = of_get_property(dp, str, &len);
426 err = 0;
427 if (!pval || len > op.op_buflen) {
428 err = -EINVAL;
429 } else {
430 op.op_buflen = len;
431 if (copy_to_user(argp, &op, sizeof(op)) ||
432 copy_to_user(op.op_buf, pval, len))
433 err = -EFAULT;
434 }
435 kfree(str);
436
437 return err;
438 }
439
440 static int opiocnextprop(void __user *argp, DATA *data)
441 {
442 struct opiocdesc op;
443 struct device_node *dp;
444 struct property *prop;
445 char *str;
446 int err, len;
447
448 if (copy_from_user(&op, argp, sizeof(op)))
449 return -EFAULT;
450
451 dp = get_node(op.op_nodeid, data);
452 if (!dp)
453 return -EINVAL;
454
455 err = copyin_string(op.op_name, op.op_namelen, &str);
456 if (err)
457 return err;
458
459 if (str[0] == '\0') {
460 prop = dp->properties;
461 } else {
462 prop = of_find_property(dp, str, NULL);
463 if (prop)
464 prop = prop->next;
465 }
466 kfree(str);
467
468 if (!prop)
469 len = 0;
470 else
471 len = prop->length;
472
473 if (len > op.op_buflen)
474 len = op.op_buflen;
475
476 if (copy_to_user(argp, &op, sizeof(op)))
477 return -EFAULT;
478
479 if (len &&
480 copy_to_user(op.op_buf, prop->value, len))
481 return -EFAULT;
482
483 return 0;
484 }
485
486 static int opiocset(void __user *argp, DATA *data)
487 {
488 struct opiocdesc op;
489 struct device_node *dp;
490 char *str, *tmp;
491 int err;
492
493 if (copy_from_user(&op, argp, sizeof(op)))
494 return -EFAULT;
495
496 dp = get_node(op.op_nodeid, data);
497 if (!dp)
498 return -EINVAL;
499
500 err = copyin_string(op.op_name, op.op_namelen, &str);
501 if (err)
502 return err;
503
504 err = copyin_string(op.op_buf, op.op_buflen, &tmp);
505 if (err) {
506 kfree(str);
507 return err;
508 }
509
510 err = of_set_property(dp, str, tmp, op.op_buflen);
511
512 kfree(str);
513 kfree(tmp);
514
515 return err;
516 }
517
518 static int opiocgetnext(unsigned int cmd, void __user *argp)
519 {
520 struct device_node *dp;
521 phandle nd;
522
523 BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
524
525 if (copy_from_user(&nd, argp, sizeof(phandle)))
526 return -EFAULT;
527
528 if (nd == 0) {
529 if (cmd != OPIOCGETNEXT)
530 return -EINVAL;
531 dp = of_find_node_by_path("/");
532 } else {
533 dp = of_find_node_by_phandle(nd);
534 nd = 0;
535 if (dp) {
536 if (cmd == OPIOCGETNEXT)
537 dp = dp->sibling;
538 else
539 dp = dp->child;
540 }
541 }
542 if (dp)
543 nd = dp->node;
544 if (copy_to_user(argp, &nd, sizeof(phandle)))
545 return -EFAULT;
546
547 return 0;
548 }
549
550 static int openprom_bsd_ioctl(struct inode * inode, struct file * file,
551 unsigned int cmd, unsigned long arg)
552 {
553 DATA *data = (DATA *) file->private_data;
554 void __user *argp = (void __user *)arg;
555 int err;
556
557 switch (cmd) {
558 case OPIOCGET:
559 err = opiocget(argp, data);
560 break;
561
562 case OPIOCNEXTPROP:
563 err = opiocnextprop(argp, data);
564 break;
565
566 case OPIOCSET:
567 err = opiocset(argp, data);
568 break;
569
570 case OPIOCGETOPTNODE:
571 BUILD_BUG_ON(sizeof(phandle) != sizeof(int));
572
573 if (copy_to_user(argp, &options_node->node, sizeof(phandle)))
574 return -EFAULT;
575
576 return 0;
577
578 case OPIOCGETNEXT:
579 case OPIOCGETCHILD:
580 err = opiocgetnext(cmd, argp);
581 break;
582
583 default:
584 return -EINVAL;
585
586 };
587
588 return err;
589 }
590
591
592 /*
593 * Handoff control to the correct ioctl handler.
594 */
595 static int openprom_ioctl(struct inode * inode, struct file * file,
596 unsigned int cmd, unsigned long arg)
597 {
598 DATA *data = (DATA *) file->private_data;
599
600 switch (cmd) {
601 case OPROMGETOPT:
602 case OPROMNXTOPT:
603 if ((file->f_mode & FMODE_READ) == 0)
604 return -EPERM;
605 return openprom_sunos_ioctl(inode, file, cmd, arg,
606 options_node);
607
608 case OPROMSETOPT:
609 case OPROMSETOPT2:
610 if ((file->f_mode & FMODE_WRITE) == 0)
611 return -EPERM;
612 return openprom_sunos_ioctl(inode, file, cmd, arg,
613 options_node);
614
615 case OPROMNEXT:
616 case OPROMCHILD:
617 case OPROMGETPROP:
618 case OPROMNXTPROP:
619 if ((file->f_mode & FMODE_READ) == 0)
620 return -EPERM;
621 return openprom_sunos_ioctl(inode, file, cmd, arg,
622 data->current_node);
623
624 case OPROMU2P:
625 case OPROMGETCONS:
626 case OPROMGETFBNAME:
627 case OPROMGETBOOTARGS:
628 case OPROMSETCUR:
629 case OPROMPCI2NODE:
630 case OPROMPATH2NODE:
631 if ((file->f_mode & FMODE_READ) == 0)
632 return -EPERM;
633 return openprom_sunos_ioctl(inode, file, cmd, arg, NULL);
634
635 case OPIOCGET:
636 case OPIOCNEXTPROP:
637 case OPIOCGETOPTNODE:
638 case OPIOCGETNEXT:
639 case OPIOCGETCHILD:
640 if ((file->f_mode & FMODE_READ) == 0)
641 return -EBADF;
642 return openprom_bsd_ioctl(inode,file,cmd,arg);
643
644 case OPIOCSET:
645 if ((file->f_mode & FMODE_WRITE) == 0)
646 return -EBADF;
647 return openprom_bsd_ioctl(inode,file,cmd,arg);
648
649 default:
650 return -EINVAL;
651 };
652 }
653
654 static long openprom_compat_ioctl(struct file *file, unsigned int cmd,
655 unsigned long arg)
656 {
657 long rval = -ENOTTY;
658
659 /*
660 * SunOS/Solaris only, the NetBSD one's have embedded pointers in
661 * the arg which we'd need to clean up...
662 */
663 switch (cmd) {
664 case OPROMGETOPT:
665 case OPROMSETOPT:
666 case OPROMNXTOPT:
667 case OPROMSETOPT2:
668 case OPROMNEXT:
669 case OPROMCHILD:
670 case OPROMGETPROP:
671 case OPROMNXTPROP:
672 case OPROMU2P:
673 case OPROMGETCONS:
674 case OPROMGETFBNAME:
675 case OPROMGETBOOTARGS:
676 case OPROMSETCUR:
677 case OPROMPCI2NODE:
678 case OPROMPATH2NODE:
679 rval = openprom_ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
680 break;
681 }
682
683 return rval;
684 }
685
686 static int openprom_open(struct inode * inode, struct file * file)
687 {
688 DATA *data;
689
690 data = kmalloc(sizeof(DATA), GFP_KERNEL);
691 if (!data)
692 return -ENOMEM;
693
694 lock_kernel();
695 data->current_node = of_find_node_by_path("/");
696 data->lastnode = data->current_node;
697 file->private_data = (void *) data;
698 unlock_kernel();
699
700 return 0;
701 }
702
703 static int openprom_release(struct inode * inode, struct file * file)
704 {
705 kfree(file->private_data);
706 return 0;
707 }
708
709 static const struct file_operations openprom_fops = {
710 .owner = THIS_MODULE,
711 .llseek = no_llseek,
712 .ioctl = openprom_ioctl,
713 .compat_ioctl = openprom_compat_ioctl,
714 .open = openprom_open,
715 .release = openprom_release,
716 };
717
718 static struct miscdevice openprom_dev = {
719 .minor = SUN_OPENPROM_MINOR,
720 .name = "openprom",
721 .fops = &openprom_fops,
722 };
723
724 static int __init openprom_init(void)
725 {
726 struct device_node *dp;
727 int err;
728
729 err = misc_register(&openprom_dev);
730 if (err)
731 return err;
732
733 dp = of_find_node_by_path("/");
734 dp = dp->child;
735 while (dp) {
736 if (!strcmp(dp->name, "options"))
737 break;
738 dp = dp->sibling;
739 }
740 options_node = dp;
741
742 if (!options_node) {
743 misc_deregister(&openprom_dev);
744 return -EIO;
745 }
746
747 return 0;
748 }
749
750 static void __exit openprom_cleanup(void)
751 {
752 misc_deregister(&openprom_dev);
753 }
754
755 module_init(openprom_init);
756 module_exit(openprom_cleanup);