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 static int debug;
51 int acpiphp_debug;
52 
53 /* local variables */
54 static int num_slots;
55 static struct acpiphp_attention_info *attention_info;
56 
57 #define DRIVER_VERSION	"0.5"
58 #define DRIVER_AUTHOR	"Greg Kroah-Hartman <gregkh@us.ibm.com>, Takayoshi Kochi <t-kochi@bq.jp.nec.com>, Matthew Wilcox <willy@hp.com>"
59 #define DRIVER_DESC	"ACPI Hot Plug PCI Controller Driver"
60 
61 MODULE_AUTHOR(DRIVER_AUTHOR);
62 MODULE_DESCRIPTION(DRIVER_DESC);
63 MODULE_LICENSE("GPL");
64 MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
65 module_param(debug, bool, 0644);
66 
67 /* export the attention callback registration methods */
68 EXPORT_SYMBOL_GPL(acpiphp_register_attention);
69 EXPORT_SYMBOL_GPL(acpiphp_unregister_attention);
70 
71 static int enable_slot		(struct hotplug_slot *slot);
72 static int disable_slot		(struct hotplug_slot *slot);
73 static int set_attention_status (struct hotplug_slot *slot, u8 value);
74 static int get_power_status	(struct hotplug_slot *slot, u8 *value);
75 static int get_attention_status (struct hotplug_slot *slot, u8 *value);
76 static int get_latch_status	(struct hotplug_slot *slot, u8 *value);
77 static int get_adapter_status	(struct hotplug_slot *slot, u8 *value);
78 
79 static struct hotplug_slot_ops acpi_hotplug_slot_ops = {
80 	.enable_slot		= enable_slot,
81 	.disable_slot		= disable_slot,
82 	.set_attention_status	= set_attention_status,
83 	.get_power_status	= get_power_status,
84 	.get_attention_status	= get_attention_status,
85 	.get_latch_status	= get_latch_status,
86 	.get_adapter_status	= get_adapter_status,
87 };
88 
89 /**
90  * acpiphp_register_attention - set attention LED callback
91  * @info: must be completely filled with LED callbacks
92  *
93  * Description: This is used to register a hardware specific ACPI
94  * driver that manipulates the attention LED.  All the fields in
95  * info must be set.
96  */
97 int acpiphp_register_attention(struct acpiphp_attention_info *info)
98 {
99 	int retval = -EINVAL;
100 
101 	if (info && info->owner && info->set_attn &&
102 			info->get_attn && !attention_info) {
103 		retval = 0;
104 		attention_info = info;
105 	}
106 	return retval;
107 }
108 
109 
110 /**
111  * acpiphp_unregister_attention - unset attention LED callback
112  * @info: must match the pointer used to register
113  *
114  * Description: This is used to un-register a hardware specific acpi
115  * driver that manipulates the attention LED.  The pointer to the
116  * info struct must be the same as the one used to set it.
117  */
118 int acpiphp_unregister_attention(struct acpiphp_attention_info *info)
119 {
120 	int retval = -EINVAL;
121 
122 	if (info && attention_info == info) {
123 		attention_info = NULL;
124 		retval = 0;
125 	}
126 	return retval;
127 }
128 
129 
130 /**
131  * enable_slot - power on and enable a slot
132  * @hotplug_slot: slot to enable
133  *
134  * Actual tasks are done in acpiphp_enable_slot()
135  */
136 static int enable_slot(struct hotplug_slot *hotplug_slot)
137 {
138 	struct slot *slot = hotplug_slot->private;
139 
140 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
141 
142 	/* enable the specified slot */
143 	return acpiphp_enable_slot(slot->acpi_slot);
144 }
145 
146 
147 /**
148  * disable_slot - disable and power off a slot
149  * @hotplug_slot: slot to disable
150  *
151  * Actual tasks are done in acpiphp_disable_slot()
152  */
153 static int disable_slot(struct hotplug_slot *hotplug_slot)
154 {
155 	struct slot *slot = hotplug_slot->private;
156 	int retval;
157 
158 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
159 
160 	/* disable the specified slot */
161 	retval = acpiphp_disable_slot(slot->acpi_slot);
162 	if (!retval)
163 		retval = acpiphp_eject_slot(slot->acpi_slot);
164 	return retval;
165 }
166 
167 
168 /**
169  * set_attention_status - set attention LED
170  * @hotplug_slot: slot to set attention LED on
171  * @status: value to set attention LED to (0 or 1)
172  *
173  * attention status LED, so we use a callback that
174  * was registered with us.  This allows hardware specific
175  * ACPI implementations to blink the light for us.
176  */
177  static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
178  {
179 	int retval = -ENODEV;
180 
181 	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot_name(hotplug_slot));
182 
183 	if (attention_info && try_module_get(attention_info->owner)) {
184 		retval = attention_info->set_attn(hotplug_slot, status);
185 		module_put(attention_info->owner);
186 	} else
187 		attention_info = NULL;
188 	return retval;
189  }
190 
191 
192 /**
193  * get_power_status - get power status of a slot
194  * @hotplug_slot: slot to get status
195  * @value: pointer to store status
196  *
197  * Some platforms may not implement _STA method properly.
198  * In that case, the value returned may not be reliable.
199  */
200 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
201 {
202 	struct slot *slot = hotplug_slot->private;
203 
204 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
205 
206 	*value = acpiphp_get_power_status(slot->acpi_slot);
207 
208 	return 0;
209 }
210 
211 
212 /**
213  * get_attention_status - get attention LED status
214  * @hotplug_slot: slot to get status from
215  * @value: returns with value of attention LED
216  *
217  * ACPI doesn't have known method to determine the state
218  * of the attention status LED, so we use a callback that
219  * was registered with us.  This allows hardware specific
220  * ACPI implementations to determine its state.
221  */
222 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
223 {
224 	int retval = -EINVAL;
225 
226 	dbg("%s - physical_slot = %s\n", __func__, hotplug_slot_name(hotplug_slot));
227 
228 	if (attention_info && try_module_get(attention_info->owner)) {
229 		retval = attention_info->get_attn(hotplug_slot, value);
230 		module_put(attention_info->owner);
231 	} else
232 		attention_info = NULL;
233 	return retval;
234 }
235 
236 
237 /**
238  * get_latch_status - get latch status of a slot
239  * @hotplug_slot: slot to get status
240  * @value: pointer to store status
241  *
242  * ACPI doesn't provide any formal means to access latch status.
243  * Instead, we fake latch status from _STA.
244  */
245 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
246 {
247 	struct slot *slot = hotplug_slot->private;
248 
249 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
250 
251 	*value = acpiphp_get_latch_status(slot->acpi_slot);
252 
253 	return 0;
254 }
255 
256 
257 /**
258  * get_adapter_status - get adapter status of a slot
259  * @hotplug_slot: slot to get status
260  * @value: pointer to store status
261  *
262  * ACPI doesn't provide any formal means to access adapter status.
263  * Instead, we fake adapter status from _STA.
264  */
265 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
266 {
267 	struct slot *slot = hotplug_slot->private;
268 
269 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
270 
271 	*value = acpiphp_get_adapter_status(slot->acpi_slot);
272 
273 	return 0;
274 }
275 
276 static int __init init_acpi(void)
277 {
278 	int retval;
279 
280 	/* initialize internal data structure etc. */
281 	retval = acpiphp_glue_init();
282 
283 	/* read initial number of slots */
284 	if (!retval) {
285 		num_slots = acpiphp_get_num_slots();
286 		if (num_slots == 0) {
287 			acpiphp_glue_exit();
288 			retval = -ENODEV;
289 		}
290 	}
291 
292 	return retval;
293 }
294 
295 /**
296  * release_slot - free up the memory used by a slot
297  * @hotplug_slot: slot to free
298  */
299 static void release_slot(struct hotplug_slot *hotplug_slot)
300 {
301 	struct slot *slot = hotplug_slot->private;
302 
303 	dbg("%s - physical_slot = %s\n", __func__, slot_name(slot));
304 
305 	kfree(slot->hotplug_slot);
306 	kfree(slot);
307 }
308 
309 /* callback routine to initialize 'struct slot' for each slot */
310 int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
311 {
312 	struct slot *slot;
313 	int retval = -ENOMEM;
314 	char name[SLOT_NAME_SIZE];
315 
316 	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
317 	if (!slot)
318 		goto error;
319 
320 	slot->hotplug_slot = kzalloc(sizeof(*slot->hotplug_slot), GFP_KERNEL);
321 	if (!slot->hotplug_slot)
322 		goto error_slot;
323 
324 	slot->hotplug_slot->info = &slot->info;
325 
326 	slot->hotplug_slot->private = slot;
327 	slot->hotplug_slot->release = &release_slot;
328 	slot->hotplug_slot->ops = &acpi_hotplug_slot_ops;
329 
330 	slot->acpi_slot = acpiphp_slot;
331 	slot->hotplug_slot->info->power_status = acpiphp_get_power_status(slot->acpi_slot);
332 	slot->hotplug_slot->info->attention_status = 0;
333 	slot->hotplug_slot->info->latch_status = acpiphp_get_latch_status(slot->acpi_slot);
334 	slot->hotplug_slot->info->adapter_status = acpiphp_get_adapter_status(slot->acpi_slot);
335 	slot->hotplug_slot->info->max_bus_speed = PCI_SPEED_UNKNOWN;
336 	slot->hotplug_slot->info->cur_bus_speed = PCI_SPEED_UNKNOWN;
337 
338 	acpiphp_slot->slot = slot;
339 	snprintf(name, SLOT_NAME_SIZE, "%llu", slot->acpi_slot->sun);
340 
341 	retval = pci_hp_register(slot->hotplug_slot,
342 					acpiphp_slot->bridge->pci_bus,
343 					acpiphp_slot->device,
344 					name);
345 	if (retval == -EBUSY)
346 		goto error_hpslot;
347 	if (retval) {
348 		err("pci_hp_register failed with error %d\n", retval);
349 		goto error_hpslot;
350  	}
351 
352 	info("Slot [%s] registered\n", slot_name(slot));
353 
354 	return 0;
355 error_hpslot:
356 	kfree(slot->hotplug_slot);
357 error_slot:
358 	kfree(slot);
359 error:
360 	return retval;
361 }
362 
363 
364 void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
365 {
366 	struct slot *slot = acpiphp_slot->slot;
367 	int retval = 0;
368 
369 	info("Slot [%s] unregistered\n", slot_name(slot));
370 
371 	retval = pci_hp_deregister(slot->hotplug_slot);
372 	if (retval)
373 		err("pci_hp_deregister failed with error %d\n", retval);
374 }
375 
376 
377 static int __init acpiphp_init(void)
378 {
379 	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
380 
381 	if (acpi_pci_disabled)
382 		return 0;
383 
384 	acpiphp_debug = debug;
385 
386 	/* read all the ACPI info from the system */
387 	return init_acpi();
388 }
389 
390 
391 static void __exit acpiphp_exit(void)
392 {
393 	if (acpi_pci_disabled)
394 		return;
395 
396 	/* deallocate internal data structures etc. */
397 	acpiphp_glue_exit();
398 }
399 
400 module_init(acpiphp_init);
401 module_exit(acpiphp_exit);
402