1/*
2 * PCI HotPlug Controller Core
3 *
4 * Copyright (C) 2001-2002 Greg Kroah-Hartman (greg@kroah.com)
5 * Copyright (C) 2001-2002 IBM Corp.
6 *
7 * All rights reserved.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or (at
12 * your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
17 * NON INFRINGEMENT.  See the GNU General Public License for more
18 * details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 *
24 * Send feedback to <kristen.c.accardi@intel.com>
25 *
26 */
27
28#include <linux/module.h>
29#include <linux/moduleparam.h>
30#include <linux/kernel.h>
31#include <linux/types.h>
32#include <linux/list.h>
33#include <linux/kobject.h>
34#include <linux/sysfs.h>
35#include <linux/pagemap.h>
36#include <linux/init.h>
37#include <linux/mount.h>
38#include <linux/namei.h>
39#include <linux/mutex.h>
40#include <linux/pci.h>
41#include <linux/pci_hotplug.h>
42#include <asm/uaccess.h>
43#include "../pci.h"
44
45#define MY_NAME	"pci_hotplug"
46
47#define dbg(fmt, arg...) do { if (debug) printk(KERN_DEBUG "%s: %s: " fmt , MY_NAME , __func__ , ## arg); } while (0)
48#define err(format, arg...) printk(KERN_ERR "%s: " format , MY_NAME , ## arg)
49#define info(format, arg...) printk(KERN_INFO "%s: " format , MY_NAME , ## arg)
50#define warn(format, arg...) printk(KERN_WARNING "%s: " format , MY_NAME , ## arg)
51
52
53/* local variables */
54static bool debug;
55
56#define DRIVER_VERSION	"0.5"
57#define DRIVER_AUTHOR	"Greg Kroah-Hartman <greg@kroah.com>, Scott Murray <scottm@somanetworks.com>"
58#define DRIVER_DESC	"PCI Hot Plug PCI Core"
59
60
61//////////////////////////////////////////////////////////////////
62
63static LIST_HEAD(pci_hotplug_slot_list);
64static DEFINE_MUTEX(pci_hp_mutex);
65
66#ifdef CONFIG_HOTPLUG_PCI_CPCI
67extern int cpci_hotplug_init(int debug);
68extern void cpci_hotplug_exit(void);
69#else
70static inline int cpci_hotplug_init(int debug) { return 0; }
71static inline void cpci_hotplug_exit(void) { }
72#endif
73
74/* Weee, fun with macros... */
75#define GET_STATUS(name,type)	\
76static int get_##name (struct hotplug_slot *slot, type *value)		\
77{									\
78	struct hotplug_slot_ops *ops = slot->ops;			\
79	int retval = 0;							\
80	if (!try_module_get(ops->owner))				\
81		return -ENODEV;						\
82	if (ops->get_##name)						\
83		retval = ops->get_##name(slot, value);			\
84	else								\
85		*value = slot->info->name;				\
86	module_put(ops->owner);						\
87	return retval;							\
88}
89
90GET_STATUS(power_status, u8)
91GET_STATUS(attention_status, u8)
92GET_STATUS(latch_status, u8)
93GET_STATUS(adapter_status, u8)
94
95static ssize_t power_read_file(struct pci_slot *slot, char *buf)
96{
97	int retval;
98	u8 value;
99
100	retval = get_power_status(slot->hotplug, &value);
101	if (retval)
102		goto exit;
103	retval = sprintf (buf, "%d\n", value);
104exit:
105	return retval;
106}
107
108static ssize_t power_write_file(struct pci_slot *pci_slot, const char *buf,
109		size_t count)
110{
111	struct hotplug_slot *slot = pci_slot->hotplug;
112	unsigned long lpower;
113	u8 power;
114	int retval = 0;
115
116	lpower = simple_strtoul (buf, NULL, 10);
117	power = (u8)(lpower & 0xff);
118	dbg ("power = %d\n", power);
119
120	if (!try_module_get(slot->ops->owner)) {
121		retval = -ENODEV;
122		goto exit;
123	}
124	switch (power) {
125		case 0:
126			if (slot->ops->disable_slot)
127				retval = slot->ops->disable_slot(slot);
128			break;
129
130		case 1:
131			if (slot->ops->enable_slot)
132				retval = slot->ops->enable_slot(slot);
133			break;
134
135		default:
136			err ("Illegal value specified for power\n");
137			retval = -EINVAL;
138	}
139	module_put(slot->ops->owner);
140
141exit:
142	if (retval)
143		return retval;
144	return count;
145}
146
147static struct pci_slot_attribute hotplug_slot_attr_power = {
148	.attr = {.name = "power", .mode = S_IFREG | S_IRUGO | S_IWUSR},
149	.show = power_read_file,
150	.store = power_write_file
151};
152
153static ssize_t attention_read_file(struct pci_slot *slot, char *buf)
154{
155	int retval;
156	u8 value;
157
158	retval = get_attention_status(slot->hotplug, &value);
159	if (retval)
160		goto exit;
161	retval = sprintf(buf, "%d\n", value);
162
163exit:
164	return retval;
165}
166
167static ssize_t attention_write_file(struct pci_slot *slot, const char *buf,
168		size_t count)
169{
170	struct hotplug_slot_ops *ops = slot->hotplug->ops;
171	unsigned long lattention;
172	u8 attention;
173	int retval = 0;
174
175	lattention = simple_strtoul (buf, NULL, 10);
176	attention = (u8)(lattention & 0xff);
177	dbg (" - attention = %d\n", attention);
178
179	if (!try_module_get(ops->owner)) {
180		retval = -ENODEV;
181		goto exit;
182	}
183	if (ops->set_attention_status)
184		retval = ops->set_attention_status(slot->hotplug, attention);
185	module_put(ops->owner);
186
187exit:
188	if (retval)
189		return retval;
190	return count;
191}
192
193static struct pci_slot_attribute hotplug_slot_attr_attention = {
194	.attr = {.name = "attention", .mode = S_IFREG | S_IRUGO | S_IWUSR},
195	.show = attention_read_file,
196	.store = attention_write_file
197};
198
199static ssize_t latch_read_file(struct pci_slot *slot, char *buf)
200{
201	int retval;
202	u8 value;
203
204	retval = get_latch_status(slot->hotplug, &value);
205	if (retval)
206		goto exit;
207	retval = sprintf (buf, "%d\n", value);
208
209exit:
210	return retval;
211}
212
213static struct pci_slot_attribute hotplug_slot_attr_latch = {
214	.attr = {.name = "latch", .mode = S_IFREG | S_IRUGO},
215	.show = latch_read_file,
216};
217
218static ssize_t presence_read_file(struct pci_slot *slot, char *buf)
219{
220	int retval;
221	u8 value;
222
223	retval = get_adapter_status(slot->hotplug, &value);
224	if (retval)
225		goto exit;
226	retval = sprintf (buf, "%d\n", value);
227
228exit:
229	return retval;
230}
231
232static struct pci_slot_attribute hotplug_slot_attr_presence = {
233	.attr = {.name = "adapter", .mode = S_IFREG | S_IRUGO},
234	.show = presence_read_file,
235};
236
237static ssize_t test_write_file(struct pci_slot *pci_slot, const char *buf,
238		size_t count)
239{
240	struct hotplug_slot *slot = pci_slot->hotplug;
241	unsigned long ltest;
242	u32 test;
243	int retval = 0;
244
245	ltest = simple_strtoul (buf, NULL, 10);
246	test = (u32)(ltest & 0xffffffff);
247	dbg ("test = %d\n", test);
248
249	if (!try_module_get(slot->ops->owner)) {
250		retval = -ENODEV;
251		goto exit;
252	}
253	if (slot->ops->hardware_test)
254		retval = slot->ops->hardware_test(slot, test);
255	module_put(slot->ops->owner);
256
257exit:
258	if (retval)
259		return retval;
260	return count;
261}
262
263static struct pci_slot_attribute hotplug_slot_attr_test = {
264	.attr = {.name = "test", .mode = S_IFREG | S_IRUGO | S_IWUSR},
265	.store = test_write_file
266};
267
268static bool has_power_file(struct pci_slot *pci_slot)
269{
270	struct hotplug_slot *slot = pci_slot->hotplug;
271	if ((!slot) || (!slot->ops))
272		return false;
273	if ((slot->ops->enable_slot) ||
274	    (slot->ops->disable_slot) ||
275	    (slot->ops->get_power_status))
276		return true;
277	return false;
278}
279
280static bool has_attention_file(struct pci_slot *pci_slot)
281{
282	struct hotplug_slot *slot = pci_slot->hotplug;
283	if ((!slot) || (!slot->ops))
284		return false;
285	if ((slot->ops->set_attention_status) ||
286	    (slot->ops->get_attention_status))
287		return true;
288	return false;
289}
290
291static bool has_latch_file(struct pci_slot *pci_slot)
292{
293	struct hotplug_slot *slot = pci_slot->hotplug;
294	if ((!slot) || (!slot->ops))
295		return false;
296	if (slot->ops->get_latch_status)
297		return true;
298	return false;
299}
300
301static bool has_adapter_file(struct pci_slot *pci_slot)
302{
303	struct hotplug_slot *slot = pci_slot->hotplug;
304	if ((!slot) || (!slot->ops))
305		return false;
306	if (slot->ops->get_adapter_status)
307		return true;
308	return false;
309}
310
311static bool has_test_file(struct pci_slot *pci_slot)
312{
313	struct hotplug_slot *slot = pci_slot->hotplug;
314	if ((!slot) || (!slot->ops))
315		return false;
316	if (slot->ops->hardware_test)
317		return true;
318	return false;
319}
320
321static int fs_add_slot(struct pci_slot *slot)
322{
323	int retval = 0;
324
325	/* Create symbolic link to the hotplug driver module */
326	pci_hp_create_module_link(slot);
327
328	if (has_power_file(slot)) {
329		retval = sysfs_create_file(&slot->kobj,
330					   &hotplug_slot_attr_power.attr);
331		if (retval)
332			goto exit_power;
333	}
334
335	if (has_attention_file(slot)) {
336		retval = sysfs_create_file(&slot->kobj,
337					   &hotplug_slot_attr_attention.attr);
338		if (retval)
339			goto exit_attention;
340	}
341
342	if (has_latch_file(slot)) {
343		retval = sysfs_create_file(&slot->kobj,
344					   &hotplug_slot_attr_latch.attr);
345		if (retval)
346			goto exit_latch;
347	}
348
349	if (has_adapter_file(slot)) {
350		retval = sysfs_create_file(&slot->kobj,
351					   &hotplug_slot_attr_presence.attr);
352		if (retval)
353			goto exit_adapter;
354	}
355
356	if (has_test_file(slot)) {
357		retval = sysfs_create_file(&slot->kobj,
358					   &hotplug_slot_attr_test.attr);
359		if (retval)
360			goto exit_test;
361	}
362
363	goto exit;
364
365exit_test:
366	if (has_adapter_file(slot))
367		sysfs_remove_file(&slot->kobj,
368				  &hotplug_slot_attr_presence.attr);
369exit_adapter:
370	if (has_latch_file(slot))
371		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_latch.attr);
372exit_latch:
373	if (has_attention_file(slot))
374		sysfs_remove_file(&slot->kobj,
375				  &hotplug_slot_attr_attention.attr);
376exit_attention:
377	if (has_power_file(slot))
378		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_power.attr);
379exit_power:
380	pci_hp_remove_module_link(slot);
381exit:
382	return retval;
383}
384
385static void fs_remove_slot(struct pci_slot *slot)
386{
387	if (has_power_file(slot))
388		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_power.attr);
389
390	if (has_attention_file(slot))
391		sysfs_remove_file(&slot->kobj,
392				  &hotplug_slot_attr_attention.attr);
393
394	if (has_latch_file(slot))
395		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_latch.attr);
396
397	if (has_adapter_file(slot))
398		sysfs_remove_file(&slot->kobj,
399				  &hotplug_slot_attr_presence.attr);
400
401	if (has_test_file(slot))
402		sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_test.attr);
403
404	pci_hp_remove_module_link(slot);
405}
406
407static struct hotplug_slot *get_slot_from_name (const char *name)
408{
409	struct hotplug_slot *slot;
410	struct list_head *tmp;
411
412	list_for_each (tmp, &pci_hotplug_slot_list) {
413		slot = list_entry (tmp, struct hotplug_slot, slot_list);
414		if (strcmp(hotplug_slot_name(slot), name) == 0)
415			return slot;
416	}
417	return NULL;
418}
419
420/**
421 * __pci_hp_register - register a hotplug_slot with the PCI hotplug subsystem
422 * @bus: bus this slot is on
423 * @slot: pointer to the &struct hotplug_slot to register
424 * @devnr: device number
425 * @name: name registered with kobject core
426 * @owner: caller module owner
427 * @mod_name: caller module name
428 *
429 * Registers a hotplug slot with the pci hotplug subsystem, which will allow
430 * userspace interaction to the slot.
431 *
432 * Returns 0 if successful, anything else for an error.
433 */
434int __pci_hp_register(struct hotplug_slot *slot, struct pci_bus *bus,
435		      int devnr, const char *name,
436		      struct module *owner, const char *mod_name)
437{
438	int result;
439	struct pci_slot *pci_slot;
440
441	if (slot == NULL)
442		return -ENODEV;
443	if ((slot->info == NULL) || (slot->ops == NULL))
444		return -EINVAL;
445	if (slot->release == NULL) {
446		dbg("Why are you trying to register a hotplug slot "
447		    "without a proper release function?\n");
448		return -EINVAL;
449	}
450
451	slot->ops->owner = owner;
452	slot->ops->mod_name = mod_name;
453
454	mutex_lock(&pci_hp_mutex);
455	/*
456	 * No problems if we call this interface from both ACPI_PCI_SLOT
457	 * driver and call it here again. If we've already created the
458	 * pci_slot, the interface will simply bump the refcount.
459	 */
460	pci_slot = pci_create_slot(bus, devnr, name, slot);
461	if (IS_ERR(pci_slot)) {
462		result = PTR_ERR(pci_slot);
463		goto out;
464	}
465
466	slot->pci_slot = pci_slot;
467	pci_slot->hotplug = slot;
468
469	list_add(&slot->slot_list, &pci_hotplug_slot_list);
470
471	result = fs_add_slot(pci_slot);
472	kobject_uevent(&pci_slot->kobj, KOBJ_ADD);
473	dbg("Added slot %s to the list\n", name);
474out:
475	mutex_unlock(&pci_hp_mutex);
476	return result;
477}
478
479/**
480 * pci_hp_deregister - deregister a hotplug_slot with the PCI hotplug subsystem
481 * @hotplug: pointer to the &struct hotplug_slot to deregister
482 *
483 * The @slot must have been registered with the pci hotplug subsystem
484 * previously with a call to pci_hp_register().
485 *
486 * Returns 0 if successful, anything else for an error.
487 */
488int pci_hp_deregister(struct hotplug_slot *hotplug)
489{
490	struct hotplug_slot *temp;
491	struct pci_slot *slot;
492
493	if (!hotplug)
494		return -ENODEV;
495
496	mutex_lock(&pci_hp_mutex);
497	temp = get_slot_from_name(hotplug_slot_name(hotplug));
498	if (temp != hotplug) {
499		mutex_unlock(&pci_hp_mutex);
500		return -ENODEV;
501	}
502
503	list_del(&hotplug->slot_list);
504
505	slot = hotplug->pci_slot;
506	fs_remove_slot(slot);
507	dbg("Removed slot %s from the list\n", hotplug_slot_name(hotplug));
508
509	hotplug->release(hotplug);
510	slot->hotplug = NULL;
511	pci_destroy_slot(slot);
512	mutex_unlock(&pci_hp_mutex);
513
514	return 0;
515}
516
517/**
518 * pci_hp_change_slot_info - changes the slot's information structure in the core
519 * @hotplug: pointer to the slot whose info has changed
520 * @info: pointer to the info copy into the slot's info structure
521 *
522 * @slot must have been registered with the pci
523 * hotplug subsystem previously with a call to pci_hp_register().
524 *
525 * Returns 0 if successful, anything else for an error.
526 */
527int __must_check pci_hp_change_slot_info(struct hotplug_slot *hotplug,
528					 struct hotplug_slot_info *info)
529{
530	struct pci_slot *slot;
531	if (!hotplug || !info)
532		return -ENODEV;
533	slot = hotplug->pci_slot;
534
535	memcpy(hotplug->info, info, sizeof(struct hotplug_slot_info));
536
537	return 0;
538}
539
540static int __init pci_hotplug_init (void)
541{
542	int result;
543
544	result = cpci_hotplug_init(debug);
545	if (result) {
546		err ("cpci_hotplug_init with error %d\n", result);
547		goto err_cpci;
548	}
549
550	info (DRIVER_DESC " version: " DRIVER_VERSION "\n");
551
552err_cpci:
553	return result;
554}
555
556static void __exit pci_hotplug_exit (void)
557{
558	cpci_hotplug_exit();
559}
560
561module_init(pci_hotplug_init);
562module_exit(pci_hotplug_exit);
563
564MODULE_AUTHOR(DRIVER_AUTHOR);
565MODULE_DESCRIPTION(DRIVER_DESC);
566MODULE_LICENSE("GPL");
567module_param(debug, bool, 0644);
568MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
569
570EXPORT_SYMBOL_GPL(__pci_hp_register);
571EXPORT_SYMBOL_GPL(pci_hp_deregister);
572EXPORT_SYMBOL_GPL(pci_hp_change_slot_info);
573