xref: /linux/drivers/pci/hotplug/acpiphp_core.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
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 static int enable_slot(struct hotplug_slot *slot);
67 static int disable_slot(struct hotplug_slot *slot);
68 static int set_attention_status(struct hotplug_slot *slot, u8 value);
69 static int get_power_status(struct hotplug_slot *slot, u8 *value);
70 static int get_attention_status(struct hotplug_slot *slot, u8 *value);
71 static int get_latch_status(struct hotplug_slot *slot, u8 *value);
72 static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
73 
74 static struct hotplug_slot_ops acpi_hotplug_slot_ops = {
75 	.enable_slot		= enable_slot,
76 	.disable_slot		= disable_slot,
77 	.set_attention_status	= set_attention_status,
78 	.get_power_status	= get_power_status,
79 	.get_attention_status	= get_attention_status,
80 	.get_latch_status	= get_latch_status,
81 	.get_adapter_status	= get_adapter_status,
82 };
83 
84 /**
85  * acpiphp_register_attention - set attention LED callback
86  * @info: must be completely filled with LED callbacks
87  *
88  * Description: This is used to register a hardware specific ACPI
89  * driver that manipulates the attention LED.  All the fields in
90  * info must be set.
91  */
92 int acpiphp_register_attention(struct acpiphp_attention_info *info)
93 {
94 	int retval = -EINVAL;
95 
96 	if (info && info->owner && info->set_attn &&
97 			info->get_attn && !attention_info) {
98 		retval = 0;
99 		attention_info = info;
100 	}
101 	return retval;
102 }
103 EXPORT_SYMBOL_GPL(acpiphp_register_attention);
104 
105 
106 /**
107  * acpiphp_unregister_attention - unset attention LED callback
108  * @info: must match the pointer used to register
109  *
110  * Description: This is used to un-register a hardware specific acpi
111  * driver that manipulates the attention LED.  The pointer to the
112  * info struct must be the same as the one used to set it.
113  */
114 int acpiphp_unregister_attention(struct acpiphp_attention_info *info)
115 {
116 	int retval = -EINVAL;
117 
118 	if (info && attention_info == info) {
119 		attention_info = NULL;
120 		retval = 0;
121 	}
122 	return retval;
123 }
124 EXPORT_SYMBOL_GPL(acpiphp_unregister_attention);
125 
126 
127 /**
128  * enable_slot - power on and enable a slot
129  * @hotplug_slot: slot to enable
130  *
131  * Actual tasks are done in acpiphp_enable_slot()
132  */
133 static int enable_slot(struct hotplug_slot *hotplug_slot)
134 {
135 	struct slot *slot = hotplug_slot->private;
136 
137 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
138 
139 	/* enable the specified slot */
140 	return acpiphp_enable_slot(slot->acpi_slot);
141 }
142 
143 
144 /**
145  * disable_slot - disable and power off a slot
146  * @hotplug_slot: slot to disable
147  *
148  * Actual tasks are done in acpiphp_disable_slot()
149  */
150 static int disable_slot(struct hotplug_slot *hotplug_slot)
151 {
152 	struct slot *slot = hotplug_slot->private;
153 
154 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
155 
156 	/* disable the specified slot */
157 	return acpiphp_disable_slot(slot->acpi_slot);
158 }
159 
160 
161 /**
162  * set_attention_status - set attention LED
163  * @hotplug_slot: slot to set attention LED on
164  * @status: value to set attention LED to (0 or 1)
165  *
166  * attention status LED, so we use a callback that
167  * was registered with us.  This allows hardware specific
168  * ACPI implementations to blink the light for us.
169  */
170 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
171 {
172 	int retval = -ENODEV;
173 
174 	pr_debug("%s - physical_slot = %s\n", __func__,
175 		hotplug_slot_name(hotplug_slot));
176 
177 	if (attention_info && try_module_get(attention_info->owner)) {
178 		retval = attention_info->set_attn(hotplug_slot, status);
179 		module_put(attention_info->owner);
180 	} else
181 		attention_info = NULL;
182 	return retval;
183 }
184 
185 
186 /**
187  * get_power_status - get power status of a slot
188  * @hotplug_slot: slot to get status
189  * @value: pointer to store status
190  *
191  * Some platforms may not implement _STA method properly.
192  * In that case, the value returned may not be reliable.
193  */
194 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
195 {
196 	struct slot *slot = hotplug_slot->private;
197 
198 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
199 
200 	*value = acpiphp_get_power_status(slot->acpi_slot);
201 
202 	return 0;
203 }
204 
205 
206 /**
207  * get_attention_status - get attention LED status
208  * @hotplug_slot: slot to get status from
209  * @value: returns with value of attention LED
210  *
211  * ACPI doesn't have known method to determine the state
212  * of the attention status LED, so we use a callback that
213  * was registered with us.  This allows hardware specific
214  * ACPI implementations to determine its state.
215  */
216 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
217 {
218 	int retval = -EINVAL;
219 
220 	pr_debug("%s - physical_slot = %s\n", __func__,
221 		hotplug_slot_name(hotplug_slot));
222 
223 	if (attention_info && try_module_get(attention_info->owner)) {
224 		retval = attention_info->get_attn(hotplug_slot, value);
225 		module_put(attention_info->owner);
226 	} else
227 		attention_info = NULL;
228 	return retval;
229 }
230 
231 
232 /**
233  * get_latch_status - get latch status of a slot
234  * @hotplug_slot: slot to get status
235  * @value: pointer to store status
236  *
237  * ACPI doesn't provide any formal means to access latch status.
238  * Instead, we fake latch status from _STA.
239  */
240 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
241 {
242 	struct slot *slot = hotplug_slot->private;
243 
244 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
245 
246 	*value = acpiphp_get_latch_status(slot->acpi_slot);
247 
248 	return 0;
249 }
250 
251 
252 /**
253  * get_adapter_status - get adapter status of a slot
254  * @hotplug_slot: slot to get status
255  * @value: pointer to store status
256  *
257  * ACPI doesn't provide any formal means to access adapter status.
258  * Instead, we fake adapter status from _STA.
259  */
260 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
261 {
262 	struct slot *slot = hotplug_slot->private;
263 
264 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
265 
266 	*value = acpiphp_get_adapter_status(slot->acpi_slot);
267 
268 	return 0;
269 }
270 
271 /**
272  * release_slot - free up the memory used by a slot
273  * @hotplug_slot: slot to free
274  */
275 static void release_slot(struct hotplug_slot *hotplug_slot)
276 {
277 	struct slot *slot = hotplug_slot->private;
278 
279 	pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
280 
281 	kfree(slot->hotplug_slot);
282 	kfree(slot);
283 }
284 
285 /* callback routine to initialize 'struct slot' for each slot */
286 int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot,
287 				  unsigned int sun)
288 {
289 	struct slot *slot;
290 	int retval = -ENOMEM;
291 	char name[SLOT_NAME_SIZE];
292 
293 	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
294 	if (!slot)
295 		goto error;
296 
297 	slot->hotplug_slot = kzalloc(sizeof(*slot->hotplug_slot), GFP_KERNEL);
298 	if (!slot->hotplug_slot)
299 		goto error_slot;
300 
301 	slot->hotplug_slot->info = &slot->info;
302 
303 	slot->hotplug_slot->private = slot;
304 	slot->hotplug_slot->release = &release_slot;
305 	slot->hotplug_slot->ops = &acpi_hotplug_slot_ops;
306 
307 	slot->acpi_slot = acpiphp_slot;
308 	slot->hotplug_slot->info->power_status = acpiphp_get_power_status(slot->acpi_slot);
309 	slot->hotplug_slot->info->attention_status = 0;
310 	slot->hotplug_slot->info->latch_status = acpiphp_get_latch_status(slot->acpi_slot);
311 	slot->hotplug_slot->info->adapter_status = acpiphp_get_adapter_status(slot->acpi_slot);
312 
313 	acpiphp_slot->slot = slot;
314 	slot->sun = sun;
315 	snprintf(name, SLOT_NAME_SIZE, "%u", sun);
316 
317 	retval = pci_hp_register(slot->hotplug_slot, acpiphp_slot->bus,
318 				 acpiphp_slot->device, name);
319 	if (retval == -EBUSY)
320 		goto error_hpslot;
321 	if (retval) {
322 		pr_err("pci_hp_register failed with error %d\n", retval);
323 		goto error_hpslot;
324 	}
325 
326 	pr_info("Slot [%s] registered\n", slot_name(slot));
327 
328 	return 0;
329 error_hpslot:
330 	kfree(slot->hotplug_slot);
331 error_slot:
332 	kfree(slot);
333 error:
334 	return retval;
335 }
336 
337 
338 void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
339 {
340 	struct slot *slot = acpiphp_slot->slot;
341 	int retval = 0;
342 
343 	pr_info("Slot [%s] unregistered\n", slot_name(slot));
344 
345 	retval = pci_hp_deregister(slot->hotplug_slot);
346 	if (retval)
347 		pr_err("pci_hp_deregister failed with error %d\n", retval);
348 }
349 
350 
351 void __init acpiphp_init(void)
352 {
353 	pr_info(DRIVER_DESC " version: " DRIVER_VERSION "%s\n",
354 		acpiphp_disabled ? ", disabled by user; please report a bug"
355 				 : "");
356 }
357