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 #define pr_fmt(fmt) "acpiphp: " fmt
35 
36 #include <linux/init.h>
37 #include <linux/module.h>
38 #include <linux/moduleparam.h>
39 
40 #include <linux/kernel.h>
41 #include <linux/pci.h>
42 #include <linux/pci-acpi.h>
43 #include <linux/pci_hotplug.h>
44 #include <linux/slab.h>
45 #include <linux/smp.h>
46 #include "acpiphp.h"
47 
48 /* name size which is used for entries in pcihpfs */
49 #define SLOT_NAME_SIZE  21              /* {_SUN} */
50 
51 bool acpiphp_disabled;
52 
53 /* local variables */
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(disable, "disable acpiphp driver");
64 module_param_named(disable, acpiphp_disabled, bool, 0444);
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 	pr_debug("%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 
156 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
157 
158 	/* disable the specified slot */
159 	return acpiphp_disable_and_eject_slot(slot->acpi_slot);
160 }
161 
162 
163 /**
164  * set_attention_status - set attention LED
165  * @hotplug_slot: slot to set attention LED on
166  * @status: value to set attention LED to (0 or 1)
167  *
168  * attention status LED, so we use a callback that
169  * was registered with us.  This allows hardware specific
170  * ACPI implementations to blink the light for us.
171  */
172 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
173 {
174 	int retval = -ENODEV;
175 
176 	pr_debug("%s - physical_slot = %s\n", __func__,
177 		hotplug_slot_name(hotplug_slot));
178 
179 	if (attention_info && try_module_get(attention_info->owner)) {
180 		retval = attention_info->set_attn(hotplug_slot, status);
181 		module_put(attention_info->owner);
182 	} else
183 		attention_info = NULL;
184 	return retval;
185 }
186 
187 
188 /**
189  * get_power_status - get power status of a slot
190  * @hotplug_slot: slot to get status
191  * @value: pointer to store status
192  *
193  * Some platforms may not implement _STA method properly.
194  * In that case, the value returned may not be reliable.
195  */
196 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
197 {
198 	struct slot *slot = hotplug_slot->private;
199 
200 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
201 
202 	*value = acpiphp_get_power_status(slot->acpi_slot);
203 
204 	return 0;
205 }
206 
207 
208 /**
209  * get_attention_status - get attention LED status
210  * @hotplug_slot: slot to get status from
211  * @value: returns with value of attention LED
212  *
213  * ACPI doesn't have known method to determine the state
214  * of the attention status LED, so we use a callback that
215  * was registered with us.  This allows hardware specific
216  * ACPI implementations to determine its state.
217  */
218 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
219 {
220 	int retval = -EINVAL;
221 
222 	pr_debug("%s - physical_slot = %s\n", __func__,
223 		hotplug_slot_name(hotplug_slot));
224 
225 	if (attention_info && try_module_get(attention_info->owner)) {
226 		retval = attention_info->get_attn(hotplug_slot, value);
227 		module_put(attention_info->owner);
228 	} else
229 		attention_info = NULL;
230 	return retval;
231 }
232 
233 
234 /**
235  * get_latch_status - get latch status of a slot
236  * @hotplug_slot: slot to get status
237  * @value: pointer to store status
238  *
239  * ACPI doesn't provide any formal means to access latch status.
240  * Instead, we fake latch status from _STA.
241  */
242 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
243 {
244 	struct slot *slot = hotplug_slot->private;
245 
246 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
247 
248 	*value = acpiphp_get_latch_status(slot->acpi_slot);
249 
250 	return 0;
251 }
252 
253 
254 /**
255  * get_adapter_status - get adapter status of a slot
256  * @hotplug_slot: slot to get status
257  * @value: pointer to store status
258  *
259  * ACPI doesn't provide any formal means to access adapter status.
260  * Instead, we fake adapter status from _STA.
261  */
262 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
263 {
264 	struct slot *slot = hotplug_slot->private;
265 
266 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
267 
268 	*value = acpiphp_get_adapter_status(slot->acpi_slot);
269 
270 	return 0;
271 }
272 
273 /**
274  * release_slot - free up the memory used by a slot
275  * @hotplug_slot: slot to free
276  */
277 static void release_slot(struct hotplug_slot *hotplug_slot)
278 {
279 	struct slot *slot = hotplug_slot->private;
280 
281 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
282 
283 	kfree(slot->hotplug_slot);
284 	kfree(slot);
285 }
286 
287 /* callback routine to initialize 'struct slot' for each slot */
288 int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot,
289 				  unsigned int sun)
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 	slot->sun = sun;
317 	snprintf(name, SLOT_NAME_SIZE, "%u", sun);
318 
319 	retval = pci_hp_register(slot->hotplug_slot, acpiphp_slot->bus,
320 				 acpiphp_slot->device, name);
321 	if (retval == -EBUSY)
322 		goto error_hpslot;
323 	if (retval) {
324 		pr_err("pci_hp_register failed with error %d\n", retval);
325 		goto error_hpslot;
326 	}
327 
328 	pr_info("Slot [%s] registered\n", slot_name(slot));
329 
330 	return 0;
331 error_hpslot:
332 	kfree(slot->hotplug_slot);
333 error_slot:
334 	kfree(slot);
335 error:
336 	return retval;
337 }
338 
339 
340 void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
341 {
342 	struct slot *slot = acpiphp_slot->slot;
343 	int retval = 0;
344 
345 	pr_info("Slot [%s] unregistered\n", slot_name(slot));
346 
347 	retval = pci_hp_deregister(slot->hotplug_slot);
348 	if (retval)
349 		pr_err("pci_hp_deregister failed with error %d\n", retval);
350 }
351 
352 
353 void __init acpiphp_init(void)
354 {
355 	pr_info(DRIVER_DESC " version: " DRIVER_VERSION "%s\n",
356 		acpiphp_disabled ? ", disabled by user; please report a bug"
357 				 : "");
358 }
359