xref: /linux/drivers/parport/procfs.c (revision fc5ced75d6dffc9e2a441520b7dc587b95281f86)
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 
do_active_device(const struct ctl_table * table,int write,void * result,size_t * lenp,loff_t * ppos)36 static int do_active_device(const struct ctl_table *table, int write,
37 		      void *result, size_t *lenp, loff_t *ppos)
38 {
39 	struct parport *port = (struct parport *)table->extra1;
40 	char buffer[256];
41 	struct pardevice *dev;
42 	int len = 0;
43 
44 	if (write)		/* can't happen anyway */
45 		return -EACCES;
46 
47 	if (*ppos) {
48 		*lenp = 0;
49 		return 0;
50 	}
51 
52 	for (dev = port->devices; dev ; dev = dev->next) {
53 		if(dev == port->cad) {
54 			len += scnprintf(buffer, sizeof(buffer), "%s\n", dev->name);
55 		}
56 	}
57 
58 	if(!len) {
59 		len += scnprintf(buffer, sizeof(buffer), "%s\n", "none");
60 	}
61 
62 	if (len > *lenp)
63 		len = *lenp;
64 	else
65 		*lenp = len;
66 
67 	*ppos += len;
68 	memcpy(result, buffer, len);
69 	return 0;
70 }
71 
72 #ifdef CONFIG_PARPORT_1284
do_autoprobe(const struct ctl_table * table,int write,void * result,size_t * lenp,loff_t * ppos)73 static int do_autoprobe(const struct ctl_table *table, int write,
74 			void *result, size_t *lenp, loff_t *ppos)
75 {
76 	struct parport_device_info *info = table->extra2;
77 	const char *str;
78 	char buffer[256];
79 	int len = 0;
80 
81 	if (write) /* permissions stop this */
82 		return -EACCES;
83 
84 	if (*ppos) {
85 		*lenp = 0;
86 		return 0;
87 	}
88 
89 	if ((str = info->class_name) != NULL)
90 		len += scnprintf (buffer + len, sizeof(buffer) - len, "CLASS:%s;\n", str);
91 
92 	if ((str = info->model) != NULL)
93 		len += scnprintf (buffer + len, sizeof(buffer) - len, "MODEL:%s;\n", str);
94 
95 	if ((str = info->mfr) != NULL)
96 		len += scnprintf (buffer + len, sizeof(buffer) - len, "MANUFACTURER:%s;\n", str);
97 
98 	if ((str = info->description) != NULL)
99 		len += scnprintf (buffer + len, sizeof(buffer) - len, "DESCRIPTION:%s;\n", str);
100 
101 	if ((str = info->cmdset) != NULL)
102 		len += scnprintf (buffer + len, sizeof(buffer) - len, "COMMAND SET:%s;\n", str);
103 
104 	if (len > *lenp)
105 		len = *lenp;
106 	else
107 		*lenp = len;
108 
109 	*ppos += len;
110 
111 	memcpy(result, buffer, len);
112 	return 0;
113 }
114 #endif /* IEEE1284.3 support. */
115 
do_hardware_base_addr(const struct ctl_table * table,int write,void * result,size_t * lenp,loff_t * ppos)116 static int do_hardware_base_addr(const struct ctl_table *table, int write,
117 				 void *result, size_t *lenp, loff_t *ppos)
118 {
119 	struct parport *port = (struct parport *)table->extra1;
120 	char buffer[64];
121 	int len = 0;
122 
123 	if (*ppos) {
124 		*lenp = 0;
125 		return 0;
126 	}
127 
128 	if (write) /* permissions prevent this anyway */
129 		return -EACCES;
130 
131 	len += scnprintf (buffer, sizeof(buffer), "%lu\t%lu\n", port->base, port->base_hi);
132 
133 	if (len > *lenp)
134 		len = *lenp;
135 	else
136 		*lenp = len;
137 
138 	*ppos += len;
139 	memcpy(result, buffer, len);
140 	return 0;
141 }
142 
do_hardware_irq(const struct ctl_table * table,int write,void * result,size_t * lenp,loff_t * ppos)143 static int do_hardware_irq(const struct ctl_table *table, int write,
144 			   void *result, size_t *lenp, loff_t *ppos)
145 {
146 	struct parport *port = (struct parport *)table->extra1;
147 	char buffer[20];
148 	int len = 0;
149 
150 	if (*ppos) {
151 		*lenp = 0;
152 		return 0;
153 	}
154 
155 	if (write) /* permissions prevent this anyway */
156 		return -EACCES;
157 
158 	len += scnprintf (buffer, sizeof(buffer), "%d\n", port->irq);
159 
160 	if (len > *lenp)
161 		len = *lenp;
162 	else
163 		*lenp = len;
164 
165 	*ppos += len;
166 	memcpy(result, buffer, len);
167 	return 0;
168 }
169 
do_hardware_dma(const struct ctl_table * table,int write,void * result,size_t * lenp,loff_t * ppos)170 static int do_hardware_dma(const struct ctl_table *table, int write,
171 			   void *result, size_t *lenp, loff_t *ppos)
172 {
173 	struct parport *port = (struct parport *)table->extra1;
174 	char buffer[20];
175 	int len = 0;
176 
177 	if (*ppos) {
178 		*lenp = 0;
179 		return 0;
180 	}
181 
182 	if (write) /* permissions prevent this anyway */
183 		return -EACCES;
184 
185 	len += scnprintf (buffer, sizeof(buffer), "%d\n", port->dma);
186 
187 	if (len > *lenp)
188 		len = *lenp;
189 	else
190 		*lenp = len;
191 
192 	*ppos += len;
193 	memcpy(result, buffer, len);
194 	return 0;
195 }
196 
do_hardware_modes(const struct ctl_table * table,int write,void * result,size_t * lenp,loff_t * ppos)197 static int do_hardware_modes(const struct ctl_table *table, int write,
198 			     void *result, size_t *lenp, loff_t *ppos)
199 {
200 	struct parport *port = (struct parport *)table->extra1;
201 	char buffer[40];
202 	int len = 0;
203 
204 	if (*ppos) {
205 		*lenp = 0;
206 		return 0;
207 	}
208 
209 	if (write) /* permissions prevent this anyway */
210 		return -EACCES;
211 
212 	{
213 #define printmode(x)							\
214 do {									\
215 	if (port->modes & PARPORT_MODE_##x)				\
216 		len += scnprintf(buffer + len, sizeof(buffer) - len, "%s%s", f++ ? "," : "", #x); \
217 } while (0)
218 		int f = 0;
219 		printmode(PCSPP);
220 		printmode(TRISTATE);
221 		printmode(COMPAT);
222 		printmode(EPP);
223 		printmode(ECP);
224 		printmode(DMA);
225 #undef printmode
226 	}
227 	buffer[len++] = '\n';
228 
229 	if (len > *lenp)
230 		len = *lenp;
231 	else
232 		*lenp = len;
233 
234 	*ppos += len;
235 	memcpy(result, buffer, len);
236 	return 0;
237 }
238 
239 static const unsigned long parport_min_timeslice_value =
240 PARPORT_MIN_TIMESLICE_VALUE;
241 
242 static const unsigned long parport_max_timeslice_value =
243 PARPORT_MAX_TIMESLICE_VALUE;
244 
245 static const  int parport_min_spintime_value =
246 PARPORT_MIN_SPINTIME_VALUE;
247 
248 static const int parport_max_spintime_value =
249 PARPORT_MAX_SPINTIME_VALUE;
250 
251 
252 struct parport_sysctl_table {
253 	struct ctl_table_header *port_header;
254 	struct ctl_table_header *devices_header;
255 #ifdef CONFIG_PARPORT_1284
256 	struct ctl_table vars[10];
257 #else
258 	struct ctl_table vars[5];
259 #endif /* IEEE 1284 support */
260 	struct ctl_table device_dir[1];
261 };
262 
263 static const struct parport_sysctl_table parport_sysctl_template = {
264 	.port_header = NULL,
265 	.devices_header = NULL,
266 	{
267 		{
268 			.procname	= "spintime",
269 			.data		= NULL,
270 			.maxlen		= sizeof(int),
271 			.mode		= 0644,
272 			.proc_handler	= proc_dointvec_minmax,
273 			.extra1		= (void*) &parport_min_spintime_value,
274 			.extra2		= (void*) &parport_max_spintime_value
275 		},
276 		{
277 			.procname	= "base-addr",
278 			.data		= NULL,
279 			.maxlen		= 0,
280 			.mode		= 0444,
281 			.proc_handler	= do_hardware_base_addr
282 		},
283 		{
284 			.procname	= "irq",
285 			.data		= NULL,
286 			.maxlen		= 0,
287 			.mode		= 0444,
288 			.proc_handler	= do_hardware_irq
289 		},
290 		{
291 			.procname	= "dma",
292 			.data		= NULL,
293 			.maxlen		= 0,
294 			.mode		= 0444,
295 			.proc_handler	= do_hardware_dma
296 		},
297 		{
298 			.procname	= "modes",
299 			.data		= NULL,
300 			.maxlen		= 0,
301 			.mode		= 0444,
302 			.proc_handler	= do_hardware_modes
303 		},
304 #ifdef CONFIG_PARPORT_1284
305 		{
306 			.procname	= "autoprobe",
307 			.data		= NULL,
308 			.maxlen		= 0,
309 			.mode		= 0444,
310 			.proc_handler	= do_autoprobe
311 		},
312 		{
313 			.procname	= "autoprobe0",
314 			.data		= NULL,
315 			.maxlen		= 0,
316 			.mode		= 0444,
317 			.proc_handler	= do_autoprobe
318 		},
319 		{
320 			.procname	= "autoprobe1",
321 			.data		= NULL,
322 			.maxlen		= 0,
323 			.mode		= 0444,
324 			.proc_handler	= do_autoprobe
325 		},
326 		{
327 			.procname	= "autoprobe2",
328 			.data		= NULL,
329 			.maxlen		= 0,
330 			.mode		= 0444,
331 			.proc_handler	= do_autoprobe
332 		},
333 		{
334 			.procname	= "autoprobe3",
335 			.data		= NULL,
336 			.maxlen		= 0,
337 			.mode		= 0444,
338 			.proc_handler	= do_autoprobe
339 		},
340 #endif /* IEEE 1284 support */
341 	},
342 	{
343 		{
344 			.procname	= "active",
345 			.data		= NULL,
346 			.maxlen		= 0,
347 			.mode		= 0444,
348 			.proc_handler	= do_active_device
349 		},
350 	},
351 };
352 
353 struct parport_device_sysctl_table
354 {
355 	struct ctl_table_header *sysctl_header;
356 	struct ctl_table vars[1];
357 	struct ctl_table device_dir[1];
358 };
359 
360 static const struct parport_device_sysctl_table
361 parport_device_sysctl_template = {
362 	.sysctl_header = NULL,
363 	{
364 		{
365 			.procname 	= "timeslice",
366 			.data		= NULL,
367 			.maxlen		= sizeof(unsigned long),
368 			.mode		= 0644,
369 			.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
370 			.extra1		= (void*) &parport_min_timeslice_value,
371 			.extra2		= (void*) &parport_max_timeslice_value
372 		},
373 	},
374 	{
375 		{
376 			.procname	= NULL,
377 			.data		= NULL,
378 			.maxlen		= 0,
379 			.mode		= 0555,
380 		},
381 	}
382 };
383 
384 struct parport_default_sysctl_table
385 {
386 	struct ctl_table_header *sysctl_header;
387 	struct ctl_table vars[2];
388 };
389 
390 static struct parport_default_sysctl_table
391 parport_default_sysctl_table = {
392 	.sysctl_header	= NULL,
393 	{
394 		{
395 			.procname	= "timeslice",
396 			.data		= &parport_default_timeslice,
397 			.maxlen		= sizeof(parport_default_timeslice),
398 			.mode		= 0644,
399 			.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
400 			.extra1		= (void*) &parport_min_timeslice_value,
401 			.extra2		= (void*) &parport_max_timeslice_value
402 		},
403 		{
404 			.procname	= "spintime",
405 			.data		= &parport_default_spintime,
406 			.maxlen		= sizeof(parport_default_spintime),
407 			.mode		= 0644,
408 			.proc_handler	= proc_dointvec_minmax,
409 			.extra1		= (void*) &parport_min_spintime_value,
410 			.extra2		= (void*) &parport_max_spintime_value
411 		},
412 	}
413 };
414 
parport_proc_register(struct parport * port)415 int parport_proc_register(struct parport *port)
416 {
417 	struct parport_sysctl_table *t;
418 	char *tmp_dir_path;
419 	int i, err = 0;
420 
421 	t = kmemdup(&parport_sysctl_template, sizeof(*t), GFP_KERNEL);
422 	if (t == NULL)
423 		return -ENOMEM;
424 
425 	t->device_dir[0].extra1 = port;
426 
427 	t->vars[0].data = &port->spintime;
428 	for (i = 0; i < 5; i++) {
429 		t->vars[i].extra1 = port;
430 #ifdef CONFIG_PARPORT_1284
431 		t->vars[5 + i].extra2 = &port->probe_info[i];
432 #endif /* IEEE 1284 support */
433 	}
434 
435 	tmp_dir_path = kasprintf(GFP_KERNEL, "dev/parport/%s/devices", port->name);
436 	if (!tmp_dir_path) {
437 		err = -ENOMEM;
438 		goto exit_free_t;
439 	}
440 
441 	t->devices_header = register_sysctl(tmp_dir_path, t->device_dir);
442 	if (t->devices_header == NULL) {
443 		err = -ENOENT;
444 		goto  exit_free_tmp_dir_path;
445 	}
446 
447 	kfree(tmp_dir_path);
448 
449 	tmp_dir_path = kasprintf(GFP_KERNEL, "dev/parport/%s", port->name);
450 	if (!tmp_dir_path) {
451 		err = -ENOMEM;
452 		goto unregister_devices_h;
453 	}
454 
455 	t->port_header = register_sysctl(tmp_dir_path, t->vars);
456 	if (t->port_header == NULL) {
457 		err = -ENOENT;
458 		goto unregister_devices_h;
459 	}
460 
461 	port->sysctl_table = t;
462 
463 	kfree(tmp_dir_path);
464 	return 0;
465 
466 unregister_devices_h:
467 	unregister_sysctl_table(t->devices_header);
468 
469 exit_free_tmp_dir_path:
470 	kfree(tmp_dir_path);
471 
472 exit_free_t:
473 	kfree(t);
474 	return err;
475 }
476 
parport_proc_unregister(struct parport * port)477 int parport_proc_unregister(struct parport *port)
478 {
479 	if (port->sysctl_table) {
480 		struct parport_sysctl_table *t = port->sysctl_table;
481 		port->sysctl_table = NULL;
482 		unregister_sysctl_table(t->devices_header);
483 		unregister_sysctl_table(t->port_header);
484 		kfree(t);
485 	}
486 	return 0;
487 }
488 
parport_device_proc_register(struct pardevice * device)489 int parport_device_proc_register(struct pardevice *device)
490 {
491 	struct parport_device_sysctl_table *t;
492 	struct parport * port = device->port;
493 	char *tmp_dir_path;
494 	int err = 0;
495 
496 	t = kmemdup(&parport_device_sysctl_template, sizeof(*t), GFP_KERNEL);
497 	if (t == NULL)
498 		return -ENOMEM;
499 
500 	/* Allocate a buffer for two paths: dev/parport/PORT/devices/DEVICE. */
501 	tmp_dir_path = kasprintf(GFP_KERNEL, "dev/parport/%s/devices/%s", port->name, device->name);
502 	if (!tmp_dir_path) {
503 		err = -ENOMEM;
504 		goto exit_free_t;
505 	}
506 
507 	t->vars[0].data = &device->timeslice;
508 
509 	t->sysctl_header = register_sysctl(tmp_dir_path, t->vars);
510 	if (t->sysctl_header == NULL) {
511 		kfree(t);
512 		t = NULL;
513 	}
514 	device->sysctl_table = t;
515 
516 	kfree(tmp_dir_path);
517 	return 0;
518 
519 exit_free_t:
520 	kfree(t);
521 
522 	return err;
523 }
524 
parport_device_proc_unregister(struct pardevice * device)525 int parport_device_proc_unregister(struct pardevice *device)
526 {
527 	if (device->sysctl_table) {
528 		struct parport_device_sysctl_table *t = device->sysctl_table;
529 		device->sysctl_table = NULL;
530 		unregister_sysctl_table(t->sysctl_header);
531 		kfree(t);
532 	}
533 	return 0;
534 }
535 
parport_default_proc_register(void)536 static int __init parport_default_proc_register(void)
537 {
538 	int ret;
539 
540 	parport_default_sysctl_table.sysctl_header =
541 		register_sysctl("dev/parport/default", parport_default_sysctl_table.vars);
542 	if (!parport_default_sysctl_table.sysctl_header)
543 		return -ENOMEM;
544 	ret = parport_bus_init();
545 	if (ret) {
546 		unregister_sysctl_table(parport_default_sysctl_table.
547 					sysctl_header);
548 		return ret;
549 	}
550 	return 0;
551 }
552 
parport_default_proc_unregister(void)553 static void __exit parport_default_proc_unregister(void)
554 {
555 	if (parport_default_sysctl_table.sysctl_header) {
556 		unregister_sysctl_table(parport_default_sysctl_table.
557 					sysctl_header);
558 		parport_default_sysctl_table.sysctl_header = NULL;
559 	}
560 	parport_bus_exit();
561 }
562 
563 #else /* no sysctl or no procfs*/
564 
parport_proc_register(struct parport * pp)565 int parport_proc_register(struct parport *pp)
566 {
567 	return 0;
568 }
569 
parport_proc_unregister(struct parport * pp)570 int parport_proc_unregister(struct parport *pp)
571 {
572 	return 0;
573 }
574 
parport_device_proc_register(struct pardevice * device)575 int parport_device_proc_register(struct pardevice *device)
576 {
577 	return 0;
578 }
579 
parport_device_proc_unregister(struct pardevice * device)580 int parport_device_proc_unregister(struct pardevice *device)
581 {
582 	return 0;
583 }
584 
parport_default_proc_register(void)585 static int __init parport_default_proc_register (void)
586 {
587 	return parport_bus_init();
588 }
589 
parport_default_proc_unregister(void)590 static void __exit parport_default_proc_unregister (void)
591 {
592 	parport_bus_exit();
593 }
594 #endif
595 
596 subsys_initcall(parport_default_proc_register)
597 module_exit(parport_default_proc_unregister)
598