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