Linux kernel mirror (for testing)
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linux
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * ACPI PCI Hot Plug Controller Driver
4 *
5 * Copyright (C) 1995,2001 Compaq Computer Corporation
6 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
7 * Copyright (C) 2001 IBM Corp.
8 * Copyright (C) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com)
9 * Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com)
10 * Copyright (C) 2002,2003 NEC Corporation
11 * Copyright (C) 2003-2005 Matthew Wilcox (willy@infradead.org)
12 * Copyright (C) 2003-2005 Hewlett Packard
13 *
14 * All rights reserved.
15 *
16 * Send feedback to <kristen.c.accardi@intel.com>
17 *
18 */
19
20#define pr_fmt(fmt) "acpiphp: " fmt
21
22#include <linux/init.h>
23#include <linux/module.h>
24#include <linux/moduleparam.h>
25
26#include <linux/kernel.h>
27#include <linux/pci.h>
28#include <linux/pci-acpi.h>
29#include <linux/pci_hotplug.h>
30#include <linux/slab.h>
31#include <linux/smp.h>
32#include "acpiphp.h"
33
34/* name size which is used for entries in pcihpfs */
35#define SLOT_NAME_SIZE 21 /* {_SUN} */
36
37bool acpiphp_disabled;
38
39/* local variables */
40static struct acpiphp_attention_info *attention_info;
41
42#define DRIVER_VERSION "0.5"
43#define DRIVER_AUTHOR "Greg Kroah-Hartman <gregkh@us.ibm.com>, Takayoshi Kochi <t-kochi@bq.jp.nec.com>, Matthew Wilcox <willy@infradead.org>"
44#define DRIVER_DESC "ACPI Hot Plug PCI Controller Driver"
45
46MODULE_AUTHOR(DRIVER_AUTHOR);
47MODULE_DESCRIPTION(DRIVER_DESC);
48MODULE_PARM_DESC(disable, "disable acpiphp driver");
49module_param_named(disable, acpiphp_disabled, bool, 0444);
50
51static int enable_slot(struct hotplug_slot *slot);
52static int disable_slot(struct hotplug_slot *slot);
53static int set_attention_status(struct hotplug_slot *slot, u8 value);
54static int get_power_status(struct hotplug_slot *slot, u8 *value);
55static int get_attention_status(struct hotplug_slot *slot, u8 *value);
56static int get_latch_status(struct hotplug_slot *slot, u8 *value);
57static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
58
59static const struct hotplug_slot_ops acpi_hotplug_slot_ops = {
60 .enable_slot = enable_slot,
61 .disable_slot = disable_slot,
62 .set_attention_status = set_attention_status,
63 .get_power_status = get_power_status,
64 .get_attention_status = get_attention_status,
65 .get_latch_status = get_latch_status,
66 .get_adapter_status = get_adapter_status,
67};
68
69/**
70 * acpiphp_register_attention - set attention LED callback
71 * @info: must be completely filled with LED callbacks
72 *
73 * Description: This is used to register a hardware specific ACPI
74 * driver that manipulates the attention LED. All the fields in
75 * info must be set.
76 */
77int acpiphp_register_attention(struct acpiphp_attention_info *info)
78{
79 int retval = -EINVAL;
80
81 if (info && info->set_attn && info->get_attn && !attention_info) {
82 retval = 0;
83 attention_info = info;
84 }
85 return retval;
86}
87EXPORT_SYMBOL_GPL(acpiphp_register_attention);
88
89
90/**
91 * acpiphp_unregister_attention - unset attention LED callback
92 * @info: must match the pointer used to register
93 *
94 * Description: This is used to un-register a hardware specific acpi
95 * driver that manipulates the attention LED. The pointer to the
96 * info struct must be the same as the one used to set it.
97 */
98int acpiphp_unregister_attention(struct acpiphp_attention_info *info)
99{
100 int retval = -EINVAL;
101
102 if (info && attention_info == info) {
103 attention_info = NULL;
104 retval = 0;
105 }
106 return retval;
107}
108EXPORT_SYMBOL_GPL(acpiphp_unregister_attention);
109
110
111/**
112 * enable_slot - power on and enable a slot
113 * @hotplug_slot: slot to enable
114 *
115 * Actual tasks are done in acpiphp_enable_slot()
116 */
117static int enable_slot(struct hotplug_slot *hotplug_slot)
118{
119 struct slot *slot = to_slot(hotplug_slot);
120
121 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
122
123 /* enable the specified slot */
124 return acpiphp_enable_slot(slot->acpi_slot);
125}
126
127
128/**
129 * disable_slot - disable and power off a slot
130 * @hotplug_slot: slot to disable
131 *
132 * Actual tasks are done in acpiphp_disable_slot()
133 */
134static int disable_slot(struct hotplug_slot *hotplug_slot)
135{
136 struct slot *slot = to_slot(hotplug_slot);
137
138 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
139
140 /* disable the specified slot */
141 return acpiphp_disable_slot(slot->acpi_slot);
142}
143
144
145/**
146 * set_attention_status - set attention LED
147 * @hotplug_slot: slot to set attention LED on
148 * @status: value to set attention LED to (0 or 1)
149 *
150 * attention status LED, so we use a callback that
151 * was registered with us. This allows hardware specific
152 * ACPI implementations to blink the light for us.
153 */
154static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
155{
156 int retval = -ENODEV;
157
158 pr_debug("%s - physical_slot = %s\n", __func__,
159 hotplug_slot_name(hotplug_slot));
160
161 if (attention_info && try_module_get(attention_info->owner)) {
162 retval = attention_info->set_attn(hotplug_slot, status);
163 module_put(attention_info->owner);
164 } else
165 attention_info = NULL;
166 return retval;
167}
168
169
170/**
171 * get_power_status - get power status of a slot
172 * @hotplug_slot: slot to get status
173 * @value: pointer to store status
174 *
175 * Some platforms may not implement _STA method properly.
176 * In that case, the value returned may not be reliable.
177 */
178static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
179{
180 struct slot *slot = to_slot(hotplug_slot);
181
182 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
183
184 *value = acpiphp_get_power_status(slot->acpi_slot);
185
186 return 0;
187}
188
189
190/**
191 * get_attention_status - get attention LED status
192 * @hotplug_slot: slot to get status from
193 * @value: returns with value of attention LED
194 *
195 * ACPI doesn't have known method to determine the state
196 * of the attention status LED, so we use a callback that
197 * was registered with us. This allows hardware specific
198 * ACPI implementations to determine its state.
199 */
200static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
201{
202 int retval = -EINVAL;
203
204 pr_debug("%s - physical_slot = %s\n", __func__,
205 hotplug_slot_name(hotplug_slot));
206
207 if (attention_info && try_module_get(attention_info->owner)) {
208 retval = attention_info->get_attn(hotplug_slot, value);
209 module_put(attention_info->owner);
210 } else
211 attention_info = NULL;
212 return retval;
213}
214
215
216/**
217 * get_latch_status - get latch status of a slot
218 * @hotplug_slot: slot to get status
219 * @value: pointer to store status
220 *
221 * ACPI doesn't provide any formal means to access latch status.
222 * Instead, we fake latch status from _STA.
223 */
224static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
225{
226 struct slot *slot = to_slot(hotplug_slot);
227
228 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
229
230 *value = acpiphp_get_latch_status(slot->acpi_slot);
231
232 return 0;
233}
234
235
236/**
237 * get_adapter_status - get adapter 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 adapter status.
242 * Instead, we fake adapter status from _STA.
243 */
244static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
245{
246 struct slot *slot = to_slot(hotplug_slot);
247
248 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
249
250 *value = acpiphp_get_adapter_status(slot->acpi_slot);
251
252 return 0;
253}
254
255/* callback routine to initialize 'struct slot' for each slot */
256int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot,
257 unsigned int sun)
258{
259 struct slot *slot;
260 int retval = -ENOMEM;
261 char name[SLOT_NAME_SIZE];
262
263 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
264 if (!slot)
265 goto error;
266
267 slot->hotplug_slot.ops = &acpi_hotplug_slot_ops;
268
269 slot->acpi_slot = acpiphp_slot;
270
271 acpiphp_slot->slot = slot;
272 slot->sun = sun;
273 snprintf(name, SLOT_NAME_SIZE, "%u", sun);
274
275 retval = pci_hp_register(&slot->hotplug_slot, acpiphp_slot->bus,
276 acpiphp_slot->device, name);
277 if (retval == -EBUSY)
278 goto error_slot;
279 if (retval) {
280 pr_err("pci_hp_register failed with error %d\n", retval);
281 goto error_slot;
282 }
283
284 pr_info("Slot [%s] registered\n", slot_name(slot));
285
286 return 0;
287error_slot:
288 kfree(slot);
289error:
290 return retval;
291}
292
293
294void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
295{
296 struct slot *slot = acpiphp_slot->slot;
297
298 pr_info("Slot [%s] unregistered\n", slot_name(slot));
299
300 pci_hp_deregister(&slot->hotplug_slot);
301 kfree(slot);
302}
303
304
305void __init acpiphp_init(void)
306{
307 pr_info(DRIVER_DESC " version: " DRIVER_VERSION "%s\n",
308 acpiphp_disabled ? ", disabled by user; please report a bug"
309 : "");
310}