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 */
54 static int 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
63 static LIST_HEAD(pci_hotplug_slot_list);
64 static DEFINE_MUTEX(pci_hp_mutex);
65
66 #ifdef CONFIG_HOTPLUG_PCI_CPCI
67 extern int cpci_hotplug_init(int debug);
68 extern void cpci_hotplug_exit(void);
69 #else
cpci_hotplug_init(int debug)70 static inline int cpci_hotplug_init(int debug) { return 0; }
cpci_hotplug_exit(void)71 static inline void cpci_hotplug_exit(void) { }
72 #endif
73
74 /* Weee, fun with macros... */
75 #define GET_STATUS(name,type) \
76 static 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
GET_STATUS(power_status,u8)90 GET_STATUS(power_status, u8)
91 GET_STATUS(attention_status, u8)
92 GET_STATUS(latch_status, u8)
93 GET_STATUS(adapter_status, u8)
94
95 static 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);
104 exit:
105 return retval;
106 }
107
power_write_file(struct pci_slot * pci_slot,const char * buf,size_t count)108 static 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
141 exit:
142 if (retval)
143 return retval;
144 return count;
145 }
146
147 static 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
attention_read_file(struct pci_slot * slot,char * buf)153 static 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
163 exit:
164 return retval;
165 }
166
attention_write_file(struct pci_slot * slot,const char * buf,size_t count)167 static 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
187 exit:
188 if (retval)
189 return retval;
190 return count;
191 }
192
193 static 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
latch_read_file(struct pci_slot * slot,char * buf)199 static 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
209 exit:
210 return retval;
211 }
212
213 static struct pci_slot_attribute hotplug_slot_attr_latch = {
214 .attr = {.name = "latch", .mode = S_IFREG | S_IRUGO},
215 .show = latch_read_file,
216 };
217
presence_read_file(struct pci_slot * slot,char * buf)218 static 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
228 exit:
229 return retval;
230 }
231
232 static struct pci_slot_attribute hotplug_slot_attr_presence = {
233 .attr = {.name = "adapter", .mode = S_IFREG | S_IRUGO},
234 .show = presence_read_file,
235 };
236
test_write_file(struct pci_slot * pci_slot,const char * buf,size_t count)237 static 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
257 exit:
258 if (retval)
259 return retval;
260 return count;
261 }
262
263 static 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
has_power_file(struct pci_slot * pci_slot)268 static 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
has_attention_file(struct pci_slot * pci_slot)280 static 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
has_latch_file(struct pci_slot * pci_slot)291 static 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
has_adapter_file(struct pci_slot * pci_slot)301 static 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
has_test_file(struct pci_slot * pci_slot)311 static 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
fs_add_slot(struct pci_slot * slot)321 static 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
365 exit_test:
366 if (has_adapter_file(slot))
367 sysfs_remove_file(&slot->kobj,
368 &hotplug_slot_attr_presence.attr);
369 exit_adapter:
370 if (has_latch_file(slot))
371 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_latch.attr);
372 exit_latch:
373 if (has_attention_file(slot))
374 sysfs_remove_file(&slot->kobj,
375 &hotplug_slot_attr_attention.attr);
376 exit_attention:
377 if (has_power_file(slot))
378 sysfs_remove_file(&slot->kobj, &hotplug_slot_attr_power.attr);
379 exit_power:
380 pci_hp_remove_module_link(slot);
381 exit:
382 return retval;
383 }
384
fs_remove_slot(struct pci_slot * slot)385 static 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
get_slot_from_name(const char * name)407 static 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 */
__pci_hp_register(struct hotplug_slot * slot,struct pci_bus * bus,int devnr,const char * name,struct module * owner,const char * mod_name)434 int __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);
474 out:
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 */
pci_hp_deregister(struct hotplug_slot * hotplug)488 int 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 */
pci_hp_change_slot_info(struct hotplug_slot * hotplug,struct hotplug_slot_info * info)527 int __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
pci_hotplug_init(void)540 static 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
552 err_cpci:
553 return result;
554 }
555
pci_hotplug_exit(void)556 static void __exit pci_hotplug_exit (void)
557 {
558 cpci_hotplug_exit();
559 }
560
561 module_init(pci_hotplug_init);
562 module_exit(pci_hotplug_exit);
563
564 MODULE_AUTHOR(DRIVER_AUTHOR);
565 MODULE_DESCRIPTION(DRIVER_DESC);
566 MODULE_LICENSE("GPL");
567 module_param(debug, bool, 0644);
568 MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
569
570 EXPORT_SYMBOL_GPL(__pci_hp_register);
571 EXPORT_SYMBOL_GPL(pci_hp_deregister);
572 EXPORT_SYMBOL_GPL(pci_hp_change_slot_info);
573