xref: /linux/drivers/pci/hotplug/acpiphp_core.c (revision c75c5ab575af7db707689cdbb5a5c458e9a034bb)
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 struct acpiphp_attention_info *attention_info;
54 
55 #define DRIVER_VERSION	"0.5"
56 #define DRIVER_AUTHOR	"Greg Kroah-Hartman <gregkh@us.ibm.com>, Takayoshi Kochi <t-kochi@bq.jp.nec.com>, Matthew Wilcox <willy@hp.com>"
57 #define DRIVER_DESC	"ACPI Hot Plug PCI Controller Driver"
58 
59 MODULE_AUTHOR(DRIVER_AUTHOR);
60 MODULE_DESCRIPTION(DRIVER_DESC);
61 MODULE_LICENSE("GPL");
62 MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
63 module_param_named(debug, acpiphp_debug, bool, 0644);
64 
65 /* export the attention callback registration methods */
66 EXPORT_SYMBOL_GPL(acpiphp_register_attention);
67 EXPORT_SYMBOL_GPL(acpiphp_unregister_attention);
68 
69 static int enable_slot		(struct hotplug_slot *slot);
70 static int disable_slot		(struct hotplug_slot *slot);
71 static int set_attention_status (struct hotplug_slot *slot, u8 value);
72 static int get_power_status	(struct hotplug_slot *slot, u8 *value);
73 static int get_attention_status (struct hotplug_slot *slot, u8 *value);
74 static int get_latch_status	(struct hotplug_slot *slot, u8 *value);
75 static int get_adapter_status	(struct hotplug_slot *slot, u8 *value);
76 
77 static struct hotplug_slot_ops acpi_hotplug_slot_ops = {
78 	.enable_slot		= enable_slot,
79 	.disable_slot		= disable_slot,
80 	.set_attention_status	= set_attention_status,
81 	.get_power_status	= get_power_status,
82 	.get_attention_status	= get_attention_status,
83 	.get_latch_status	= get_latch_status,
84 	.get_adapter_status	= get_adapter_status,
85 };
86 
87 /**
88  * acpiphp_register_attention - set attention LED callback
89  * @info: must be completely filled with LED callbacks
90  *
91  * Description: This is used to register a hardware specific ACPI
92  * driver that manipulates the attention LED.  All the fields in
93  * info must be set.
94  */
95 int acpiphp_register_attention(struct acpiphp_attention_info *info)
96 {
97 	int retval = -EINVAL;
98 
99 	if (info && info->owner && info->set_attn &&
100 			info->get_attn && !attention_info) {
101 		retval = 0;
102 		attention_info = info;
103 	}
104 	return retval;
105 }
106 
107 
108 /**
109  * acpiphp_unregister_attention - unset attention LED callback
110  * @info: must match the pointer used to register
111  *
112  * Description: This is used to un-register a hardware specific acpi
113  * driver that manipulates the attention LED.  The pointer to the
114  * info struct must be the same as the one used to set it.
115  */
116 int acpiphp_unregister_attention(struct acpiphp_attention_info *info)
117 {
118 	int retval = -EINVAL;
119 
120 	if (info && attention_info == info) {
121 		attention_info = NULL;
122 		retval = 0;
123 	}
124 	return retval;
125 }
126 
127 
128 /**
129  * enable_slot - power on and enable a slot
130  * @hotplug_slot: slot to enable
131  *
132  * Actual tasks are done in acpiphp_enable_slot()
133  */
134 static int enable_slot(struct hotplug_slot *hotplug_slot)
135 {
136 	struct slot *slot = hotplug_slot->private;
137 
138 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
139 
140 	/* enable the specified slot */
141 	return acpiphp_enable_slot(slot->acpi_slot);
142 }
143 
144 
145 /**
146  * disable_slot - disable and power off a slot
147  * @hotplug_slot: slot to disable
148  *
149  * Actual tasks are done in acpiphp_disable_slot()
150  */
151 static int disable_slot(struct hotplug_slot *hotplug_slot)
152 {
153 	struct slot *slot = hotplug_slot->private;
154 	int retval;
155 
156 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
157 
158 	/* disable the specified slot */
159 	retval = acpiphp_disable_slot(slot->acpi_slot);
160 	if (!retval)
161 		retval = acpiphp_eject_slot(slot->acpi_slot);
162 	return retval;
163 }
164 
165 
166 /**
167  * set_attention_status - set attention LED
168  * @hotplug_slot: slot to set attention LED on
169  * @status: value to set attention LED to (0 or 1)
170  *
171  * attention status LED, so we use a callback that
172  * was registered with us.  This allows hardware specific
173  * ACPI implementations to blink the light for us.
174  */
175  static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
176  {
177 	int retval = -ENODEV;
178 
179 	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot_name(hotplug_slot));
180 
181 	if (attention_info && try_module_get(attention_info->owner)) {
182 		retval = attention_info->set_attn(hotplug_slot, status);
183 		module_put(attention_info->owner);
184 	} else
185 		attention_info = NULL;
186 	return retval;
187  }
188 
189 
190 /**
191  * get_power_status - get power status of a slot
192  * @hotplug_slot: slot to get status
193  * @value: pointer to store status
194  *
195  * Some platforms may not implement _STA method properly.
196  * In that case, the value returned may not be reliable.
197  */
198 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
199 {
200 	struct slot *slot = hotplug_slot->private;
201 
202 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
203 
204 	*value = acpiphp_get_power_status(slot->acpi_slot);
205 
206 	return 0;
207 }
208 
209 
210 /**
211  * get_attention_status - get attention LED status
212  * @hotplug_slot: slot to get status from
213  * @value: returns with value of attention LED
214  *
215  * ACPI doesn't have known method to determine the state
216  * of the attention status LED, so we use a callback that
217  * was registered with us.  This allows hardware specific
218  * ACPI implementations to determine its state.
219  */
220 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
221 {
222 	int retval = -EINVAL;
223 
224 	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot_name(hotplug_slot));
225 
226 	if (attention_info && try_module_get(attention_info->owner)) {
227 		retval = attention_info->get_attn(hotplug_slot, value);
228 		module_put(attention_info->owner);
229 	} else
230 		attention_info = NULL;
231 	return retval;
232 }
233 
234 
235 /**
236  * get_latch_status - get latch status of a slot
237  * @hotplug_slot: slot to get status
238  * @value: pointer to store status
239  *
240  * ACPI doesn't provide any formal means to access latch status.
241  * Instead, we fake latch status from _STA.
242  */
243 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
244 {
245 	struct slot *slot = hotplug_slot->private;
246 
247 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
248 
249 	*value = acpiphp_get_latch_status(slot->acpi_slot);
250 
251 	return 0;
252 }
253 
254 
255 /**
256  * get_adapter_status - get adapter status of a slot
257  * @hotplug_slot: slot to get status
258  * @value: pointer to store status
259  *
260  * ACPI doesn't provide any formal means to access adapter status.
261  * Instead, we fake adapter status from _STA.
262  */
263 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
264 {
265 	struct slot *slot = hotplug_slot->private;
266 
267 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
268 
269 	*value = acpiphp_get_adapter_status(slot->acpi_slot);
270 
271 	return 0;
272 }
273 
274 /**
275  * release_slot - free up the memory used by a slot
276  * @hotplug_slot: slot to free
277  */
278 static void release_slot(struct hotplug_slot *hotplug_slot)
279 {
280 	struct slot *slot = hotplug_slot->private;
281 
282 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
283 
284 	kfree(slot->hotplug_slot);
285 	kfree(slot);
286 }
287 
288 /* callback routine to initialize 'struct slot' for each slot */
289 int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
290 {
291 	struct slot *slot;
292 	int retval = -ENOMEM;
293 	char name[SLOT_NAME_SIZE];
294 
295 	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
296 	if (!slot)
297 		goto error;
298 
299 	slot->hotplug_slot = kzalloc(sizeof(*slot->hotplug_slot), GFP_KERNEL);
300 	if (!slot->hotplug_slot)
301 		goto error_slot;
302 
303 	slot->hotplug_slot->info = &slot->info;
304 
305 	slot->hotplug_slot->private = slot;
306 	slot->hotplug_slot->release = &release_slot;
307 	slot->hotplug_slot->ops = &acpi_hotplug_slot_ops;
308 
309 	slot->acpi_slot = acpiphp_slot;
310 	slot->hotplug_slot->info->power_status = acpiphp_get_power_status(slot->acpi_slot);
311 	slot->hotplug_slot->info->attention_status = 0;
312 	slot->hotplug_slot->info->latch_status = acpiphp_get_latch_status(slot->acpi_slot);
313 	slot->hotplug_slot->info->adapter_status = acpiphp_get_adapter_status(slot->acpi_slot);
314 
315 	acpiphp_slot->slot = slot;
316 	snprintf(name, SLOT_NAME_SIZE, "%llu", slot->acpi_slot->sun);
317 
318 	retval = pci_hp_register(slot->hotplug_slot,
319 					acpiphp_slot->bridge->pci_bus,
320 					acpiphp_slot->device,
321 					name);
322 	if (retval == -EBUSY)
323 		goto error_hpslot;
324 	if (retval) {
325 		err("pci_hp_register failed with error %d\n", retval);
326 		goto error_hpslot;
327  	}
328 
329 	info("Slot [%s] registered\n", slot_name(slot));
330 
331 	return 0;
332 error_hpslot:
333 	kfree(slot->hotplug_slot);
334 error_slot:
335 	kfree(slot);
336 error:
337 	return retval;
338 }
339 
340 
341 void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
342 {
343 	struct slot *slot = acpiphp_slot->slot;
344 	int retval = 0;
345 
346 	info("Slot [%s] unregistered\n", slot_name(slot));
347 
348 	retval = pci_hp_deregister(slot->hotplug_slot);
349 	if (retval)
350 		err("pci_hp_deregister failed with error %d\n", retval);
351 }
352 
353 
354 static int __init acpiphp_init(void)
355 {
356 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
357 
358 	if (acpi_pci_disabled)
359 		return 0;
360 
361 	/* read all the ACPI info from the system */
362 	/* initialize internal data structure etc. */
363 	return acpiphp_glue_init();
364 }
365 
366 
367 static void __exit acpiphp_exit(void)
368 {
369 	if (acpi_pci_disabled)
370 		return;
371 
372 	/* deallocate internal data structures etc. */
373 	acpiphp_glue_exit();
374 }
375 
376 module_init(acpiphp_init);
377 module_exit(acpiphp_exit);
378