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
43static 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
80static 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
123static 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
150static 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
177static 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
204static 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)							\
221do {									\
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
246static const unsigned long parport_min_timeslice_value =
247PARPORT_MIN_TIMESLICE_VALUE;
248
249static const unsigned long parport_max_timeslice_value =
250PARPORT_MAX_TIMESLICE_VALUE;
251
252static const  int parport_min_spintime_value =
253PARPORT_MIN_SPINTIME_VALUE;
254
255static const int parport_max_spintime_value =
256PARPORT_MAX_SPINTIME_VALUE;
257
258
259struct parport_sysctl_table {
260	struct ctl_table_header *port_header;
261	struct ctl_table_header *devices_header;
262	struct ctl_table vars[12];
263	struct ctl_table device_dir[2];
264};
265
266static const struct parport_sysctl_table parport_sysctl_template = {
267	.port_header = NULL,
268	.devices_header = NULL,
269	{
270		{
271			.procname	= "spintime",
272			.data		= NULL,
273			.maxlen		= sizeof(int),
274			.mode		= 0644,
275			.proc_handler	= proc_dointvec_minmax,
276			.extra1		= (void*) &parport_min_spintime_value,
277			.extra2		= (void*) &parport_max_spintime_value
278		},
279		{
280			.procname	= "base-addr",
281			.data		= NULL,
282			.maxlen		= 0,
283			.mode		= 0444,
284			.proc_handler	= do_hardware_base_addr
285		},
286		{
287			.procname	= "irq",
288			.data		= NULL,
289			.maxlen		= 0,
290			.mode		= 0444,
291			.proc_handler	= do_hardware_irq
292		},
293		{
294			.procname	= "dma",
295			.data		= NULL,
296			.maxlen		= 0,
297			.mode		= 0444,
298			.proc_handler	= do_hardware_dma
299		},
300		{
301			.procname	= "modes",
302			.data		= NULL,
303			.maxlen		= 0,
304			.mode		= 0444,
305			.proc_handler	= do_hardware_modes
306		},
307#ifdef CONFIG_PARPORT_1284
308		{
309			.procname	= "autoprobe",
310			.data		= NULL,
311			.maxlen		= 0,
312			.mode		= 0444,
313			.proc_handler	= do_autoprobe
314		},
315		{
316			.procname	= "autoprobe0",
317			.data		= NULL,
318			.maxlen		= 0,
319			.mode		= 0444,
320			.proc_handler	= do_autoprobe
321		},
322		{
323			.procname	= "autoprobe1",
324			.data		= NULL,
325			.maxlen		= 0,
326			.mode		= 0444,
327			.proc_handler	= do_autoprobe
328		},
329		{
330			.procname	= "autoprobe2",
331			.data		= NULL,
332			.maxlen		= 0,
333			.mode		= 0444,
334			.proc_handler	= do_autoprobe
335		},
336		{
337			.procname	= "autoprobe3",
338			.data		= NULL,
339			.maxlen		= 0,
340			.mode		= 0444,
341			.proc_handler	= do_autoprobe
342		},
343#endif /* IEEE 1284 support */
344		{}
345	},
346	{
347		{
348			.procname	= "active",
349			.data		= NULL,
350			.maxlen		= 0,
351			.mode		= 0444,
352			.proc_handler	= do_active_device
353		},
354		{}
355	},
356};
357
358struct parport_device_sysctl_table
359{
360	struct ctl_table_header *sysctl_header;
361	struct ctl_table vars[2];
362	struct ctl_table device_dir[2];
363	struct ctl_table devices_root_dir[2];
364	struct ctl_table port_dir[2];
365	struct ctl_table parport_dir[2];
366	struct ctl_table dev_dir[2];
367};
368
369static const struct parport_device_sysctl_table
370parport_device_sysctl_template = {
371	.sysctl_header = NULL,
372	{
373		{
374			.procname 	= "timeslice",
375			.data		= NULL,
376			.maxlen		= sizeof(unsigned long),
377			.mode		= 0644,
378			.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
379			.extra1		= (void*) &parport_min_timeslice_value,
380			.extra2		= (void*) &parport_max_timeslice_value
381		},
382		{}
383	},
384	{
385		{
386			.procname	= NULL,
387			.data		= NULL,
388			.maxlen		= 0,
389			.mode		= 0555,
390		},
391		{}
392	}
393};
394
395struct parport_default_sysctl_table
396{
397	struct ctl_table_header *sysctl_header;
398	struct ctl_table vars[3];
399	struct ctl_table default_dir[2];
400	struct ctl_table parport_dir[2];
401	struct ctl_table dev_dir[2];
402};
403
404static struct parport_default_sysctl_table
405parport_default_sysctl_table = {
406	.sysctl_header	= NULL,
407	{
408		{
409			.procname	= "timeslice",
410			.data		= &parport_default_timeslice,
411			.maxlen		= sizeof(parport_default_timeslice),
412			.mode		= 0644,
413			.proc_handler	= proc_doulongvec_ms_jiffies_minmax,
414			.extra1		= (void*) &parport_min_timeslice_value,
415			.extra2		= (void*) &parport_max_timeslice_value
416		},
417		{
418			.procname	= "spintime",
419			.data		= &parport_default_spintime,
420			.maxlen		= sizeof(parport_default_spintime),
421			.mode		= 0644,
422			.proc_handler	= proc_dointvec_minmax,
423			.extra1		= (void*) &parport_min_spintime_value,
424			.extra2		= (void*) &parport_max_spintime_value
425		},
426		{}
427	}
428};
429
430int parport_proc_register(struct parport *port)
431{
432	struct parport_sysctl_table *t;
433	char *tmp_dir_path;
434	size_t tmp_path_len, port_name_len;
435	int bytes_written, i, err = 0;
436
437	t = kmemdup(&parport_sysctl_template, sizeof(*t), GFP_KERNEL);
438	if (t == NULL)
439		return -ENOMEM;
440
441	t->device_dir[0].extra1 = port;
442
443	t->vars[0].data = &port->spintime;
444	for (i = 0; i < 5; i++) {
445		t->vars[i].extra1 = port;
446		t->vars[5 + i].extra2 = &port->probe_info[i];
447	}
448
449	port_name_len = strnlen(port->name, PARPORT_NAME_MAX_LEN);
450	/*
451	 * Allocate a buffer for two paths: dev/parport/PORT and dev/parport/PORT/devices.
452	 * We calculate for the second as that will give us enough for the first.
453	 */
454	tmp_path_len = PARPORT_BASE_DEVICES_PATH_SIZE + port_name_len;
455	tmp_dir_path = kzalloc(tmp_path_len, GFP_KERNEL);
456	if (!tmp_dir_path) {
457		err = -ENOMEM;
458		goto exit_free_t;
459	}
460
461	bytes_written = snprintf(tmp_dir_path, tmp_path_len,
462				 "dev/parport/%s/devices", port->name);
463	if (tmp_path_len <= bytes_written) {
464		err = -ENOENT;
465		goto exit_free_tmp_dir_path;
466	}
467	t->devices_header = register_sysctl(tmp_dir_path, t->device_dir);
468	if (t->devices_header == NULL) {
469		err = -ENOENT;
470		goto  exit_free_tmp_dir_path;
471	}
472
473	tmp_path_len = PARPORT_BASE_PATH_SIZE + port_name_len;
474	bytes_written = snprintf(tmp_dir_path, tmp_path_len,
475				 "dev/parport/%s", port->name);
476	if (tmp_path_len <= bytes_written) {
477		err = -ENOENT;
478		goto unregister_devices_h;
479	}
480
481	t->port_header = register_sysctl(tmp_dir_path, t->vars);
482	if (t->port_header == NULL) {
483		err = -ENOENT;
484		goto unregister_devices_h;
485	}
486
487	port->sysctl_table = t;
488
489	kfree(tmp_dir_path);
490	return 0;
491
492unregister_devices_h:
493	unregister_sysctl_table(t->devices_header);
494
495exit_free_tmp_dir_path:
496	kfree(tmp_dir_path);
497
498exit_free_t:
499	kfree(t);
500	return err;
501}
502
503int parport_proc_unregister(struct parport *port)
504{
505	if (port->sysctl_table) {
506		struct parport_sysctl_table *t = port->sysctl_table;
507		port->sysctl_table = NULL;
508		unregister_sysctl_table(t->devices_header);
509		unregister_sysctl_table(t->port_header);
510		kfree(t);
511	}
512	return 0;
513}
514
515int parport_device_proc_register(struct pardevice *device)
516{
517	int bytes_written, err = 0;
518	struct parport_device_sysctl_table *t;
519	struct parport * port = device->port;
520	size_t port_name_len, device_name_len, tmp_dir_path_len;
521	char *tmp_dir_path;
522
523	t = kmemdup(&parport_device_sysctl_template, sizeof(*t), GFP_KERNEL);
524	if (t == NULL)
525		return -ENOMEM;
526
527	port_name_len = strnlen(port->name, PARPORT_NAME_MAX_LEN);
528	device_name_len = strnlen(device->name, PATH_MAX);
529
530	/* Allocate a buffer for two paths: dev/parport/PORT/devices/DEVICE. */
531	tmp_dir_path_len = PARPORT_BASE_DEVICES_PATH_SIZE + port_name_len + device_name_len;
532	tmp_dir_path = kzalloc(tmp_dir_path_len, GFP_KERNEL);
533	if (!tmp_dir_path) {
534		err = -ENOMEM;
535		goto exit_free_t;
536	}
537
538	bytes_written = snprintf(tmp_dir_path, tmp_dir_path_len, "dev/parport/%s/devices/%s",
539				 port->name, device->name);
540	if (tmp_dir_path_len <= bytes_written) {
541		err = -ENOENT;
542		goto exit_free_path;
543	}
544
545	t->vars[0].data = &device->timeslice;
546
547	t->sysctl_header = register_sysctl(tmp_dir_path, t->vars);
548	if (t->sysctl_header == NULL) {
549		kfree(t);
550		t = NULL;
551	}
552	device->sysctl_table = t;
553
554	kfree(tmp_dir_path);
555	return 0;
556
557exit_free_path:
558	kfree(tmp_dir_path);
559
560exit_free_t:
561	kfree(t);
562
563	return err;
564}
565
566int parport_device_proc_unregister(struct pardevice *device)
567{
568	if (device->sysctl_table) {
569		struct parport_device_sysctl_table *t = device->sysctl_table;
570		device->sysctl_table = NULL;
571		unregister_sysctl_table(t->sysctl_header);
572		kfree(t);
573	}
574	return 0;
575}
576
577static int __init parport_default_proc_register(void)
578{
579	int ret;
580
581	parport_default_sysctl_table.sysctl_header =
582		register_sysctl("dev/parport/default", parport_default_sysctl_table.vars);
583	if (!parport_default_sysctl_table.sysctl_header)
584		return -ENOMEM;
585	ret = parport_bus_init();
586	if (ret) {
587		unregister_sysctl_table(parport_default_sysctl_table.
588					sysctl_header);
589		return ret;
590	}
591	return 0;
592}
593
594static void __exit parport_default_proc_unregister(void)
595{
596	if (parport_default_sysctl_table.sysctl_header) {
597		unregister_sysctl_table(parport_default_sysctl_table.
598					sysctl_header);
599		parport_default_sysctl_table.sysctl_header = NULL;
600	}
601	parport_bus_exit();
602}
603
604#else /* no sysctl or no procfs*/
605
606int parport_proc_register(struct parport *pp)
607{
608	return 0;
609}
610
611int parport_proc_unregister(struct parport *pp)
612{
613	return 0;
614}
615
616int parport_device_proc_register(struct pardevice *device)
617{
618	return 0;
619}
620
621int parport_device_proc_unregister(struct pardevice *device)
622{
623	return 0;
624}
625
626static int __init parport_default_proc_register (void)
627{
628	return parport_bus_init();
629}
630
631static void __exit parport_default_proc_unregister (void)
632{
633	parport_bus_exit();
634}
635#endif
636
637subsys_initcall(parport_default_proc_register)
638module_exit(parport_default_proc_unregister)
639