xref: /linux/drivers/pci/hotplug/acpiphp_core.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * ACPI PCI Hot Plug Controller Driver
3  *
4  * Copyright (C) 1995,2001 Compaq Computer Corporation
5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
6  * Copyright (C) 2001 IBM Corp.
7  * Copyright (C) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com)
8  * Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com)
9  * Copyright (C) 2002,2003 NEC Corporation
10  * Copyright (C) 2003-2005 Matthew Wilcox (matthew.wilcox@hp.com)
11  * Copyright (C) 2003-2005 Hewlett Packard
12  *
13  * All rights reserved.
14  *
15  * This program is free software; you can redistribute it and/or modify
16  * it under the terms of the GNU General Public License as published by
17  * the Free Software Foundation; either version 2 of the License, or (at
18  * your option) any later version.
19  *
20  * This program is distributed in the hope that it will be useful, but
21  * WITHOUT ANY WARRANTY; without even the implied warranty of
22  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
23  * NON INFRINGEMENT.  See the GNU General Public License for more
24  * details.
25  *
26  * You should have received a copy of the GNU General Public License
27  * along with this program; if not, write to the Free Software
28  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
29  *
30  * Send feedback to <kristen.c.accardi@intel.com>
31  *
32  */
33 
34 #include <linux/init.h>
35 #include <linux/module.h>
36 #include <linux/moduleparam.h>
37 
38 #include <linux/kernel.h>
39 #include <linux/pci.h>
40 #include <linux/pci_hotplug.h>
41 #include <linux/slab.h>
42 #include <linux/smp.h>
43 #include "acpiphp.h"
44 
45 #define MY_NAME	"acpiphp"
46 
47 /* name size which is used for entries in pcihpfs */
48 #define SLOT_NAME_SIZE  21              /* {_SUN} */
49 
50 bool acpiphp_debug;
51 
52 /* local variables */
53 static int num_slots;
54 static struct acpiphp_attention_info *attention_info;
55 
56 #define DRIVER_VERSION	"0.5"
57 #define DRIVER_AUTHOR	"Greg Kroah-Hartman <gregkh@us.ibm.com>, Takayoshi Kochi <t-kochi@bq.jp.nec.com>, Matthew Wilcox <willy@hp.com>"
58 #define DRIVER_DESC	"ACPI Hot Plug PCI Controller Driver"
59 
60 MODULE_AUTHOR(DRIVER_AUTHOR);
61 MODULE_DESCRIPTION(DRIVER_DESC);
62 MODULE_LICENSE("GPL");
63 MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
64 module_param_named(debug, acpiphp_debug, bool, 0644);
65 
66 /* export the attention callback registration methods */
67 EXPORT_SYMBOL_GPL(acpiphp_register_attention);
68 EXPORT_SYMBOL_GPL(acpiphp_unregister_attention);
69 
70 static int enable_slot		(struct hotplug_slot *slot);
71 static int disable_slot		(struct hotplug_slot *slot);
72 static int set_attention_status (struct hotplug_slot *slot, u8 value);
73 static int get_power_status	(struct hotplug_slot *slot, u8 *value);
74 static int get_attention_status (struct hotplug_slot *slot, u8 *value);
75 static int get_latch_status	(struct hotplug_slot *slot, u8 *value);
76 static int get_adapter_status	(struct hotplug_slot *slot, u8 *value);
77 
78 static struct hotplug_slot_ops acpi_hotplug_slot_ops = {
79 	.enable_slot		= enable_slot,
80 	.disable_slot		= disable_slot,
81 	.set_attention_status	= set_attention_status,
82 	.get_power_status	= get_power_status,
83 	.get_attention_status	= get_attention_status,
84 	.get_latch_status	= get_latch_status,
85 	.get_adapter_status	= get_adapter_status,
86 };
87 
88 /**
89  * acpiphp_register_attention - set attention LED callback
90  * @info: must be completely filled with LED callbacks
91  *
92  * Description: This is used to register a hardware specific ACPI
93  * driver that manipulates the attention LED.  All the fields in
94  * info must be set.
95  */
96 int acpiphp_register_attention(struct acpiphp_attention_info *info)
97 {
98 	int retval = -EINVAL;
99 
100 	if (info && info->owner && info->set_attn &&
101 			info->get_attn && !attention_info) {
102 		retval = 0;
103 		attention_info = info;
104 	}
105 	return retval;
106 }
107 
108 
109 /**
110  * acpiphp_unregister_attention - unset attention LED callback
111  * @info: must match the pointer used to register
112  *
113  * Description: This is used to un-register a hardware specific acpi
114  * driver that manipulates the attention LED.  The pointer to the
115  * info struct must be the same as the one used to set it.
116  */
117 int acpiphp_unregister_attention(struct acpiphp_attention_info *info)
118 {
119 	int retval = -EINVAL;
120 
121 	if (info && attention_info == info) {
122 		attention_info = NULL;
123 		retval = 0;
124 	}
125 	return retval;
126 }
127 
128 
129 /**
130  * enable_slot - power on and enable a slot
131  * @hotplug_slot: slot to enable
132  *
133  * Actual tasks are done in acpiphp_enable_slot()
134  */
135 static int enable_slot(struct hotplug_slot *hotplug_slot)
136 {
137 	struct slot *slot = hotplug_slot->private;
138 
139 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
140 
141 	/* enable the specified slot */
142 	return acpiphp_enable_slot(slot->acpi_slot);
143 }
144 
145 
146 /**
147  * disable_slot - disable and power off a slot
148  * @hotplug_slot: slot to disable
149  *
150  * Actual tasks are done in acpiphp_disable_slot()
151  */
152 static int disable_slot(struct hotplug_slot *hotplug_slot)
153 {
154 	struct slot *slot = hotplug_slot->private;
155 	int retval;
156 
157 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
158 
159 	/* disable the specified slot */
160 	retval = acpiphp_disable_slot(slot->acpi_slot);
161 	if (!retval)
162 		retval = acpiphp_eject_slot(slot->acpi_slot);
163 	return retval;
164 }
165 
166 
167 /**
168  * set_attention_status - set attention LED
169  * @hotplug_slot: slot to set attention LED on
170  * @status: value to set attention LED to (0 or 1)
171  *
172  * attention status LED, so we use a callback that
173  * was registered with us.  This allows hardware specific
174  * ACPI implementations to blink the light for us.
175  */
176  static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
177  {
178 	int retval = -ENODEV;
179 
180 	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot_name(hotplug_slot));
181 
182 	if (attention_info && try_module_get(attention_info->owner)) {
183 		retval = attention_info->set_attn(hotplug_slot, status);
184 		module_put(attention_info->owner);
185 	} else
186 		attention_info = NULL;
187 	return retval;
188  }
189 
190 
191 /**
192  * get_power_status - get power status of a slot
193  * @hotplug_slot: slot to get status
194  * @value: pointer to store status
195  *
196  * Some platforms may not implement _STA method properly.
197  * In that case, the value returned may not be reliable.
198  */
199 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
200 {
201 	struct slot *slot = hotplug_slot->private;
202 
203 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
204 
205 	*value = acpiphp_get_power_status(slot->acpi_slot);
206 
207 	return 0;
208 }
209 
210 
211 /**
212  * get_attention_status - get attention LED status
213  * @hotplug_slot: slot to get status from
214  * @value: returns with value of attention LED
215  *
216  * ACPI doesn't have known method to determine the state
217  * of the attention status LED, so we use a callback that
218  * was registered with us.  This allows hardware specific
219  * ACPI implementations to determine its state.
220  */
221 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
222 {
223 	int retval = -EINVAL;
224 
225 	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot_name(hotplug_slot));
226 
227 	if (attention_info && try_module_get(attention_info->owner)) {
228 		retval = attention_info->get_attn(hotplug_slot, value);
229 		module_put(attention_info->owner);
230 	} else
231 		attention_info = NULL;
232 	return retval;
233 }
234 
235 
236 /**
237  * get_latch_status - get latch status of a slot
238  * @hotplug_slot: slot to get status
239  * @value: pointer to store status
240  *
241  * ACPI doesn't provide any formal means to access latch status.
242  * Instead, we fake latch status from _STA.
243  */
244 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
245 {
246 	struct slot *slot = hotplug_slot->private;
247 
248 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
249 
250 	*value = acpiphp_get_latch_status(slot->acpi_slot);
251 
252 	return 0;
253 }
254 
255 
256 /**
257  * get_adapter_status - get adapter status of a slot
258  * @hotplug_slot: slot to get status
259  * @value: pointer to store status
260  *
261  * ACPI doesn't provide any formal means to access adapter status.
262  * Instead, we fake adapter status from _STA.
263  */
264 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
265 {
266 	struct slot *slot = hotplug_slot->private;
267 
268 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
269 
270 	*value = acpiphp_get_adapter_status(slot->acpi_slot);
271 
272 	return 0;
273 }
274 
275 static int __init init_acpi(void)
276 {
277 	int retval;
278 
279 	/* initialize internal data structure etc. */
280 	retval = acpiphp_glue_init();
281 
282 	/* read initial number of slots */
283 	if (!retval) {
284 		num_slots = acpiphp_get_num_slots();
285 		if (num_slots == 0) {
286 			acpiphp_glue_exit();
287 			retval = -ENODEV;
288 		}
289 	}
290 
291 	return retval;
292 }
293 
294 /**
295  * release_slot - free up the memory used by a slot
296  * @hotplug_slot: slot to free
297  */
298 static void release_slot(struct hotplug_slot *hotplug_slot)
299 {
300 	struct slot *slot = hotplug_slot->private;
301 
302 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
303 
304 	kfree(slot->hotplug_slot);
305 	kfree(slot);
306 }
307 
308 /* callback routine to initialize 'struct slot' for each slot */
309 int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
310 {
311 	struct slot *slot;
312 	int retval = -ENOMEM;
313 	char name[SLOT_NAME_SIZE];
314 
315 	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
316 	if (!slot)
317 		goto error;
318 
319 	slot->hotplug_slot = kzalloc(sizeof(*slot->hotplug_slot), GFP_KERNEL);
320 	if (!slot->hotplug_slot)
321 		goto error_slot;
322 
323 	slot->hotplug_slot->info = &slot->info;
324 
325 	slot->hotplug_slot->private = slot;
326 	slot->hotplug_slot->release = &release_slot;
327 	slot->hotplug_slot->ops = &acpi_hotplug_slot_ops;
328 
329 	slot->acpi_slot = acpiphp_slot;
330 	slot->hotplug_slot->info->power_status = acpiphp_get_power_status(slot->acpi_slot);
331 	slot->hotplug_slot->info->attention_status = 0;
332 	slot->hotplug_slot->info->latch_status = acpiphp_get_latch_status(slot->acpi_slot);
333 	slot->hotplug_slot->info->adapter_status = acpiphp_get_adapter_status(slot->acpi_slot);
334 
335 	acpiphp_slot->slot = slot;
336 	snprintf(name, SLOT_NAME_SIZE, "%llu", slot->acpi_slot->sun);
337 
338 	retval = pci_hp_register(slot->hotplug_slot,
339 					acpiphp_slot->bridge->pci_bus,
340 					acpiphp_slot->device,
341 					name);
342 	if (retval == -EBUSY)
343 		goto error_hpslot;
344 	if (retval) {
345 		err("pci_hp_register failed with error %d\n", retval);
346 		goto error_hpslot;
347  	}
348 
349 	info("Slot [%s] registered\n", slot_name(slot));
350 
351 	return 0;
352 error_hpslot:
353 	kfree(slot->hotplug_slot);
354 error_slot:
355 	kfree(slot);
356 error:
357 	return retval;
358 }
359 
360 
361 void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
362 {
363 	struct slot *slot = acpiphp_slot->slot;
364 	int retval = 0;
365 
366 	info("Slot [%s] unregistered\n", slot_name(slot));
367 
368 	retval = pci_hp_deregister(slot->hotplug_slot);
369 	if (retval)
370 		err("pci_hp_deregister failed with error %d\n", retval);
371 }
372 
373 
374 static int __init acpiphp_init(void)
375 {
376 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
377 
378 	if (acpi_pci_disabled)
379 		return 0;
380 
381 	/* read all the ACPI info from the system */
382 	return init_acpi();
383 }
384 
385 
386 static void __exit acpiphp_exit(void)
387 {
388 	if (acpi_pci_disabled)
389 		return;
390 
391 	/* deallocate internal data structures etc. */
392 	acpiphp_glue_exit();
393 }
394 
395 module_init(acpiphp_init);
396 module_exit(acpiphp_exit);
397