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