xref: /linux/drivers/parport/procfs.c (revision ecae0bd5173b1014f95a14a8dfbe40ec10367dcf)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Sysctl interface for parport devices.
3  *
4  * Authors: David Campbell
5  *          Tim Waugh <tim@cyberelk.demon.co.uk>
6  *          Philip Blundell <philb@gnu.org>
7  *          Andrea Arcangeli
8  *          Riccardo Facchetti <fizban@tin.it>
9  *
10  * based on work by Grant Guenther <grant@torque.net>
11  *              and Philip Blundell
12  *
13  * Cleaned up include files - Russell King <linux@arm.uk.linux.org>
14  */
15 
16 #include <linux/string.h>
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/errno.h>
20 #include <linux/kernel.h>
21 #include <linux/slab.h>
22 #include <linux/parport.h>
23 #include <linux/ctype.h>
24 #include <linux/sysctl.h>
25 #include <linux/device.h>
26 
27 #include <linux/uaccess.h>
28 
29 #if defined(CONFIG_SYSCTL) && defined(CONFIG_PROC_FS)
30 
31 #define PARPORT_MIN_TIMESLICE_VALUE 1ul
32 #define PARPORT_MAX_TIMESLICE_VALUE ((unsigned long) HZ)
33 #define PARPORT_MIN_SPINTIME_VALUE 1
34 #define PARPORT_MAX_SPINTIME_VALUE 1000
35 /*
36  * PARPORT_BASE_* is the size of the known parts of the sysctl path
37  * in dev/partport/%s/devices/%s. "dev/parport/"(12), "/devices/"(9
38  * and null char(1).
39  */
40 #define PARPORT_BASE_PATH_SIZE 13
41 #define PARPORT_BASE_DEVICES_PATH_SIZE 22
42 
43 static int do_active_device(struct ctl_table *table, int write,
44 		      void *result, size_t *lenp, loff_t *ppos)
45 {
46 	struct parport *port = (struct parport *)table->extra1;
47 	char buffer[256];
48 	struct pardevice *dev;
49 	int len = 0;
50 
51 	if (write)		/* can't happen anyway */
52 		return -EACCES;
53 
54 	if (*ppos) {
55 		*lenp = 0;
56 		return 0;
57 	}
58 
59 	for (dev = port->devices; dev ; dev = dev->next) {
60 		if(dev == port->cad) {
61 			len += sprintf(buffer, "%s\n", dev->name);
62 		}
63 	}
64 
65 	if(!len) {
66 		len += sprintf(buffer, "%s\n", "none");
67 	}
68 
69 	if (len > *lenp)
70 		len = *lenp;
71 	else
72 		*lenp = len;
73 
74 	*ppos += len;
75 	memcpy(result, buffer, len);
76 	return 0;
77 }
78 
79 #ifdef CONFIG_PARPORT_1284
80 static int do_autoprobe(struct ctl_table *table, int write,
81 			void *result, size_t *lenp, loff_t *ppos)
82 {
83 	struct parport_device_info *info = table->extra2;
84 	const char *str;
85 	char buffer[256];
86 	int len = 0;
87 
88 	if (write) /* permissions stop this */
89 		return -EACCES;
90 
91 	if (*ppos) {
92 		*lenp = 0;
93 		return 0;
94 	}
95 
96 	if ((str = info->class_name) != NULL)
97 		len += sprintf (buffer + len, "CLASS:%s;\n", str);
98 
99 	if ((str = info->model) != NULL)
100 		len += sprintf (buffer + len, "MODEL:%s;\n", str);
101 
102 	if ((str = info->mfr) != NULL)
103 		len += sprintf (buffer + len, "MANUFACTURER:%s;\n", str);
104 
105 	if ((str = info->description) != NULL)
106 		len += sprintf (buffer + len, "DESCRIPTION:%s;\n", str);
107 
108 	if ((str = info->cmdset) != NULL)
109 		len += sprintf (buffer + len, "COMMAND SET:%s;\n", str);
110 
111 	if (len > *lenp)
112 		len = *lenp;
113 	else
114 		*lenp = len;
115 
116 	*ppos += len;
117 
118 	memcpy(result, buffer, len);
119 	return 0;
120 }
121 #endif /* IEEE1284.3 support. */
122 
123 static int do_hardware_base_addr(struct ctl_table *table, int write,
124 				 void *result, size_t *lenp, loff_t *ppos)
125 {
126 	struct parport *port = (struct parport *)table->extra1;
127 	char buffer[20];
128 	int len = 0;
129 
130 	if (*ppos) {
131 		*lenp = 0;
132 		return 0;
133 	}
134 
135 	if (write) /* permissions prevent this anyway */
136 		return -EACCES;
137 
138 	len += sprintf (buffer, "%lu\t%lu\n", port->base, port->base_hi);
139 
140 	if (len > *lenp)
141 		len = *lenp;
142 	else
143 		*lenp = len;
144 
145 	*ppos += len;
146 	memcpy(result, buffer, len);
147 	return 0;
148 }
149 
150 static int do_hardware_irq(struct ctl_table *table, int write,
151 			   void *result, size_t *lenp, loff_t *ppos)
152 {
153 	struct parport *port = (struct parport *)table->extra1;
154 	char buffer[20];
155 	int len = 0;
156 
157 	if (*ppos) {
158 		*lenp = 0;
159 		return 0;
160 	}
161 
162 	if (write) /* permissions prevent this anyway */
163 		return -EACCES;
164 
165 	len += sprintf (buffer, "%d\n", port->irq);
166 
167 	if (len > *lenp)
168 		len = *lenp;
169 	else
170 		*lenp = len;
171 
172 	*ppos += len;
173 	memcpy(result, buffer, len);
174 	return 0;
175 }
176 
177 static int do_hardware_dma(struct ctl_table *table, int write,
178 			   void *result, size_t *lenp, loff_t *ppos)
179 {
180 	struct parport *port = (struct parport *)table->extra1;
181 	char buffer[20];
182 	int len = 0;
183 
184 	if (*ppos) {
185 		*lenp = 0;
186 		return 0;
187 	}
188 
189 	if (write) /* permissions prevent this anyway */
190 		return -EACCES;
191 
192 	len += sprintf (buffer, "%d\n", port->dma);
193 
194 	if (len > *lenp)
195 		len = *lenp;
196 	else
197 		*lenp = len;
198 
199 	*ppos += len;
200 	memcpy(result, buffer, len);
201 	return 0;
202 }
203 
204 static int do_hardware_modes(struct ctl_table *table, int write,
205 			     void *result, size_t *lenp, loff_t *ppos)
206 {
207 	struct parport *port = (struct parport *)table->extra1;
208 	char buffer[40];
209 	int len = 0;
210 
211 	if (*ppos) {
212 		*lenp = 0;
213 		return 0;
214 	}
215 
216 	if (write) /* permissions prevent this anyway */
217 		return -EACCES;
218 
219 	{
220 #define printmode(x)							\
221 do {									\
222 	if (port->modes & PARPORT_MODE_##x)				\
223 		len += sprintf(buffer + len, "%s%s", f++ ? "," : "", #x); \
224 } while (0)
225 		int f = 0;
226 		printmode(PCSPP);
227 		printmode(TRISTATE);
228 		printmode(COMPAT);
229 		printmode(EPP);
230 		printmode(ECP);
231 		printmode(DMA);
232 #undef printmode
233 	}
234 	buffer[len++] = '\n';
235 
236 	if (len > *lenp)
237 		len = *lenp;
238 	else
239 		*lenp = len;
240 
241 	*ppos += len;
242 	memcpy(result, buffer, len);
243 	return 0;
244 }
245 
246 static const unsigned long parport_min_timeslice_value =
247 PARPORT_MIN_TIMESLICE_VALUE;
248 
249 static const unsigned long parport_max_timeslice_value =
250 PARPORT_MAX_TIMESLICE_VALUE;
251 
252 static const  int parport_min_spintime_value =
253 PARPORT_MIN_SPINTIME_VALUE;
254 
255 static const int parport_max_spintime_value =
256 PARPORT_MAX_SPINTIME_VALUE;
257 
258 
259 struct parport_sysctl_table {
260 	struct ctl_table_header *port_header;
261 	struct ctl_table_header *devices_header;
262 #ifdef CONFIG_PARPORT_1284
263 	struct ctl_table vars[10];
264 #else
265 	struct ctl_table vars[5];
266 #endif /* IEEE 1284 support */
267 	struct ctl_table device_dir[1];
268 };
269 
270 static const struct parport_sysctl_table parport_sysctl_template = {
271 	.port_header = NULL,
272 	.devices_header = NULL,
273 	{
274 		{
275 			.procname	= "spintime",
276 			.data		= NULL,
277 			.maxlen		= sizeof(int),
278 			.mode		= 0644,
279 			.proc_handler	= proc_dointvec_minmax,
280 			.extra1		= (void*) &parport_min_spintime_value,
281 			.extra2		= (void*) &parport_max_spintime_value
282 		},
283 		{
284 			.procname	= "base-addr",
285 			.data		= NULL,
286 			.maxlen		= 0,
287 			.mode		= 0444,
288 			.proc_handler	= do_hardware_base_addr
289 		},
290 		{
291 			.procname	= "irq",
292 			.data		= NULL,
293 			.maxlen		= 0,
294 			.mode		= 0444,
295 			.proc_handler	= do_hardware_irq
296 		},
297 		{
298 			.procname	= "dma",
299 			.data		= NULL,
300 			.maxlen		= 0,
301 			.mode		= 0444,
302 			.proc_handler	= do_hardware_dma
303 		},
304 		{
305 			.procname	= "modes",
306 			.data		= NULL,
307 			.maxlen		= 0,
308 			.mode		= 0444,
309 			.proc_handler	= do_hardware_modes
310 		},
311 #ifdef CONFIG_PARPORT_1284
312 		{
313 			.procname	= "autoprobe",
314 			.data		= NULL,
315 			.maxlen		= 0,
316 			.mode		= 0444,
317 			.proc_handler	= do_autoprobe
318 		},
319 		{
320 			.procname	= "autoprobe0",
321 			.data		= NULL,
322 			.maxlen		= 0,
323 			.mode		= 0444,
324 			.proc_handler	= do_autoprobe
325 		},
326 		{
327 			.procname	= "autoprobe1",
328 			.data		= NULL,
329 			.maxlen		= 0,
330 			.mode		= 0444,
331 			.proc_handler	= do_autoprobe
332 		},
333 		{
334 			.procname	= "autoprobe2",
335 			.data		= NULL,
336 			.maxlen		= 0,
337 			.mode		= 0444,
338 			.proc_handler	= do_autoprobe
339 		},
340 		{
341 			.procname	= "autoprobe3",
342 			.data		= NULL,
343 			.maxlen		= 0,
344 			.mode		= 0444,
345 			.proc_handler	= do_autoprobe
346 		},
347 #endif /* IEEE 1284 support */
348 	},
349 	{
350 		{
351 			.procname	= "active",
352 			.data		= NULL,
353 			.maxlen		= 0,
354 			.mode		= 0444,
355 			.proc_handler	= do_active_device
356 		},
357 	},
358 };
359 
360 struct parport_device_sysctl_table
361 {
362 	struct ctl_table_header *sysctl_header;
363 	struct ctl_table vars[1];
364 	struct ctl_table device_dir[1];
365 };
366 
367 static const struct parport_device_sysctl_table
368 parport_device_sysctl_template = {
369 	.sysctl_header = NULL,
370 	{
371 		{
372 			.procname 	= "timeslice",
373 			.data		= NULL,
374 			.maxlen		= sizeof(unsigned long),
375 			.mode		= 0644,
376 			.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
377 			.extra1		= (void*) &parport_min_timeslice_value,
378 			.extra2		= (void*) &parport_max_timeslice_value
379 		},
380 	},
381 	{
382 		{
383 			.procname	= NULL,
384 			.data		= NULL,
385 			.maxlen		= 0,
386 			.mode		= 0555,
387 		},
388 	}
389 };
390 
391 struct parport_default_sysctl_table
392 {
393 	struct ctl_table_header *sysctl_header;
394 	struct ctl_table vars[2];
395 };
396 
397 static struct parport_default_sysctl_table
398 parport_default_sysctl_table = {
399 	.sysctl_header	= NULL,
400 	{
401 		{
402 			.procname	= "timeslice",
403 			.data		= &parport_default_timeslice,
404 			.maxlen		= sizeof(parport_default_timeslice),
405 			.mode		= 0644,
406 			.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
407 			.extra1		= (void*) &parport_min_timeslice_value,
408 			.extra2		= (void*) &parport_max_timeslice_value
409 		},
410 		{
411 			.procname	= "spintime",
412 			.data		= &parport_default_spintime,
413 			.maxlen		= sizeof(parport_default_spintime),
414 			.mode		= 0644,
415 			.proc_handler	= proc_dointvec_minmax,
416 			.extra1		= (void*) &parport_min_spintime_value,
417 			.extra2		= (void*) &parport_max_spintime_value
418 		},
419 	}
420 };
421 
422 int parport_proc_register(struct parport *port)
423 {
424 	struct parport_sysctl_table *t;
425 	char *tmp_dir_path;
426 	size_t tmp_path_len, port_name_len;
427 	int bytes_written, i, err = 0;
428 
429 	t = kmemdup(&parport_sysctl_template, sizeof(*t), GFP_KERNEL);
430 	if (t == NULL)
431 		return -ENOMEM;
432 
433 	t->device_dir[0].extra1 = port;
434 
435 	t->vars[0].data = &port->spintime;
436 	for (i = 0; i < 5; i++) {
437 		t->vars[i].extra1 = port;
438 #ifdef CONFIG_PARPORT_1284
439 		t->vars[5 + i].extra2 = &port->probe_info[i];
440 #endif /* IEEE 1284 support */
441 	}
442 
443 	port_name_len = strnlen(port->name, PARPORT_NAME_MAX_LEN);
444 	/*
445 	 * Allocate a buffer for two paths: dev/parport/PORT and dev/parport/PORT/devices.
446 	 * We calculate for the second as that will give us enough for the first.
447 	 */
448 	tmp_path_len = PARPORT_BASE_DEVICES_PATH_SIZE + port_name_len;
449 	tmp_dir_path = kzalloc(tmp_path_len, GFP_KERNEL);
450 	if (!tmp_dir_path) {
451 		err = -ENOMEM;
452 		goto exit_free_t;
453 	}
454 
455 	bytes_written = snprintf(tmp_dir_path, tmp_path_len,
456 				 "dev/parport/%s/devices", port->name);
457 	if (tmp_path_len <= bytes_written) {
458 		err = -ENOENT;
459 		goto exit_free_tmp_dir_path;
460 	}
461 	t->devices_header = register_sysctl(tmp_dir_path, t->device_dir);
462 	if (t->devices_header == NULL) {
463 		err = -ENOENT;
464 		goto  exit_free_tmp_dir_path;
465 	}
466 
467 	tmp_path_len = PARPORT_BASE_PATH_SIZE + port_name_len;
468 	bytes_written = snprintf(tmp_dir_path, tmp_path_len,
469 				 "dev/parport/%s", port->name);
470 	if (tmp_path_len <= bytes_written) {
471 		err = -ENOENT;
472 		goto unregister_devices_h;
473 	}
474 
475 	t->port_header = register_sysctl(tmp_dir_path, t->vars);
476 	if (t->port_header == NULL) {
477 		err = -ENOENT;
478 		goto unregister_devices_h;
479 	}
480 
481 	port->sysctl_table = t;
482 
483 	kfree(tmp_dir_path);
484 	return 0;
485 
486 unregister_devices_h:
487 	unregister_sysctl_table(t->devices_header);
488 
489 exit_free_tmp_dir_path:
490 	kfree(tmp_dir_path);
491 
492 exit_free_t:
493 	kfree(t);
494 	return err;
495 }
496 
497 int parport_proc_unregister(struct parport *port)
498 {
499 	if (port->sysctl_table) {
500 		struct parport_sysctl_table *t = port->sysctl_table;
501 		port->sysctl_table = NULL;
502 		unregister_sysctl_table(t->devices_header);
503 		unregister_sysctl_table(t->port_header);
504 		kfree(t);
505 	}
506 	return 0;
507 }
508 
509 int parport_device_proc_register(struct pardevice *device)
510 {
511 	int bytes_written, err = 0;
512 	struct parport_device_sysctl_table *t;
513 	struct parport * port = device->port;
514 	size_t port_name_len, device_name_len, tmp_dir_path_len;
515 	char *tmp_dir_path;
516 
517 	t = kmemdup(&parport_device_sysctl_template, sizeof(*t), GFP_KERNEL);
518 	if (t == NULL)
519 		return -ENOMEM;
520 
521 	port_name_len = strnlen(port->name, PARPORT_NAME_MAX_LEN);
522 	device_name_len = strnlen(device->name, PATH_MAX);
523 
524 	/* Allocate a buffer for two paths: dev/parport/PORT/devices/DEVICE. */
525 	tmp_dir_path_len = PARPORT_BASE_DEVICES_PATH_SIZE + port_name_len + device_name_len;
526 	tmp_dir_path = kzalloc(tmp_dir_path_len, GFP_KERNEL);
527 	if (!tmp_dir_path) {
528 		err = -ENOMEM;
529 		goto exit_free_t;
530 	}
531 
532 	bytes_written = snprintf(tmp_dir_path, tmp_dir_path_len, "dev/parport/%s/devices/%s",
533 				 port->name, device->name);
534 	if (tmp_dir_path_len <= bytes_written) {
535 		err = -ENOENT;
536 		goto exit_free_path;
537 	}
538 
539 	t->vars[0].data = &device->timeslice;
540 
541 	t->sysctl_header = register_sysctl(tmp_dir_path, t->vars);
542 	if (t->sysctl_header == NULL) {
543 		kfree(t);
544 		t = NULL;
545 	}
546 	device->sysctl_table = t;
547 
548 	kfree(tmp_dir_path);
549 	return 0;
550 
551 exit_free_path:
552 	kfree(tmp_dir_path);
553 
554 exit_free_t:
555 	kfree(t);
556 
557 	return err;
558 }
559 
560 int parport_device_proc_unregister(struct pardevice *device)
561 {
562 	if (device->sysctl_table) {
563 		struct parport_device_sysctl_table *t = device->sysctl_table;
564 		device->sysctl_table = NULL;
565 		unregister_sysctl_table(t->sysctl_header);
566 		kfree(t);
567 	}
568 	return 0;
569 }
570 
571 static int __init parport_default_proc_register(void)
572 {
573 	int ret;
574 
575 	parport_default_sysctl_table.sysctl_header =
576 		register_sysctl("dev/parport/default", parport_default_sysctl_table.vars);
577 	if (!parport_default_sysctl_table.sysctl_header)
578 		return -ENOMEM;
579 	ret = parport_bus_init();
580 	if (ret) {
581 		unregister_sysctl_table(parport_default_sysctl_table.
582 					sysctl_header);
583 		return ret;
584 	}
585 	return 0;
586 }
587 
588 static void __exit parport_default_proc_unregister(void)
589 {
590 	if (parport_default_sysctl_table.sysctl_header) {
591 		unregister_sysctl_table(parport_default_sysctl_table.
592 					sysctl_header);
593 		parport_default_sysctl_table.sysctl_header = NULL;
594 	}
595 	parport_bus_exit();
596 }
597 
598 #else /* no sysctl or no procfs*/
599 
600 int parport_proc_register(struct parport *pp)
601 {
602 	return 0;
603 }
604 
605 int parport_proc_unregister(struct parport *pp)
606 {
607 	return 0;
608 }
609 
610 int parport_device_proc_register(struct pardevice *device)
611 {
612 	return 0;
613 }
614 
615 int parport_device_proc_unregister(struct pardevice *device)
616 {
617 	return 0;
618 }
619 
620 static int __init parport_default_proc_register (void)
621 {
622 	return parport_bus_init();
623 }
624 
625 static void __exit parport_default_proc_unregister (void)
626 {
627 	parport_bus_exit();
628 }
629 #endif
630 
631 subsys_initcall(parport_default_proc_register)
632 module_exit(parport_default_proc_unregister)
633