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
37 bool acpiphp_disabled;
38
39 /* local variables */
40 static 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
46 MODULE_AUTHOR(DRIVER_AUTHOR);
47 MODULE_DESCRIPTION(DRIVER_DESC);
48 MODULE_LICENSE("GPL");
49 MODULE_PARM_DESC(disable, "disable acpiphp driver");
50 module_param_named(disable, acpiphp_disabled, bool, 0444);
51
52 static int enable_slot(struct hotplug_slot *slot);
53 static int disable_slot(struct hotplug_slot *slot);
54 static int set_attention_status(struct hotplug_slot *slot, u8 value);
55 static int get_power_status(struct hotplug_slot *slot, u8 *value);
56 static int get_attention_status(struct hotplug_slot *slot, u8 *value);
57 static int get_latch_status(struct hotplug_slot *slot, u8 *value);
58 static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
59
60 static const struct hotplug_slot_ops acpi_hotplug_slot_ops = {
61 .enable_slot = enable_slot,
62 .disable_slot = disable_slot,
63 .set_attention_status = set_attention_status,
64 .get_power_status = get_power_status,
65 .get_attention_status = get_attention_status,
66 .get_latch_status = get_latch_status,
67 .get_adapter_status = get_adapter_status,
68 };
69
70 /**
71 * acpiphp_register_attention - set attention LED callback
72 * @info: must be completely filled with LED callbacks
73 *
74 * Description: This is used to register a hardware specific ACPI
75 * driver that manipulates the attention LED. All the fields in
76 * info must be set.
77 */
acpiphp_register_attention(struct acpiphp_attention_info * info)78 int acpiphp_register_attention(struct acpiphp_attention_info *info)
79 {
80 int retval = -EINVAL;
81
82 if (info && info->owner && info->set_attn &&
83 info->get_attn && !attention_info) {
84 retval = 0;
85 attention_info = info;
86 }
87 return retval;
88 }
89 EXPORT_SYMBOL_GPL(acpiphp_register_attention);
90
91
92 /**
93 * acpiphp_unregister_attention - unset attention LED callback
94 * @info: must match the pointer used to register
95 *
96 * Description: This is used to un-register a hardware specific acpi
97 * driver that manipulates the attention LED. The pointer to the
98 * info struct must be the same as the one used to set it.
99 */
acpiphp_unregister_attention(struct acpiphp_attention_info * info)100 int acpiphp_unregister_attention(struct acpiphp_attention_info *info)
101 {
102 int retval = -EINVAL;
103
104 if (info && attention_info == info) {
105 attention_info = NULL;
106 retval = 0;
107 }
108 return retval;
109 }
110 EXPORT_SYMBOL_GPL(acpiphp_unregister_attention);
111
112
113 /**
114 * enable_slot - power on and enable a slot
115 * @hotplug_slot: slot to enable
116 *
117 * Actual tasks are done in acpiphp_enable_slot()
118 */
enable_slot(struct hotplug_slot * hotplug_slot)119 static int enable_slot(struct hotplug_slot *hotplug_slot)
120 {
121 struct slot *slot = to_slot(hotplug_slot);
122
123 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
124
125 /* enable the specified slot */
126 return acpiphp_enable_slot(slot->acpi_slot);
127 }
128
129
130 /**
131 * disable_slot - disable and power off a slot
132 * @hotplug_slot: slot to disable
133 *
134 * Actual tasks are done in acpiphp_disable_slot()
135 */
disable_slot(struct hotplug_slot * hotplug_slot)136 static int disable_slot(struct hotplug_slot *hotplug_slot)
137 {
138 struct slot *slot = to_slot(hotplug_slot);
139
140 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
141
142 /* disable the specified slot */
143 return acpiphp_disable_slot(slot->acpi_slot);
144 }
145
146
147 /**
148 * set_attention_status - set attention LED
149 * @hotplug_slot: slot to set attention LED on
150 * @status: value to set attention LED to (0 or 1)
151 *
152 * attention status LED, so we use a callback that
153 * was registered with us. This allows hardware specific
154 * ACPI implementations to blink the light for us.
155 */
set_attention_status(struct hotplug_slot * hotplug_slot,u8 status)156 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
157 {
158 int retval = -ENODEV;
159
160 pr_debug("%s - physical_slot = %s\n", __func__,
161 hotplug_slot_name(hotplug_slot));
162
163 if (attention_info && try_module_get(attention_info->owner)) {
164 retval = attention_info->set_attn(hotplug_slot, status);
165 module_put(attention_info->owner);
166 } else
167 attention_info = NULL;
168 return retval;
169 }
170
171
172 /**
173 * get_power_status - get power status of a slot
174 * @hotplug_slot: slot to get status
175 * @value: pointer to store status
176 *
177 * Some platforms may not implement _STA method properly.
178 * In that case, the value returned may not be reliable.
179 */
get_power_status(struct hotplug_slot * hotplug_slot,u8 * value)180 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
181 {
182 struct slot *slot = to_slot(hotplug_slot);
183
184 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
185
186 *value = acpiphp_get_power_status(slot->acpi_slot);
187
188 return 0;
189 }
190
191
192 /**
193 * get_attention_status - get attention LED status
194 * @hotplug_slot: slot to get status from
195 * @value: returns with value of attention LED
196 *
197 * ACPI doesn't have known method to determine the state
198 * of the attention status LED, so we use a callback that
199 * was registered with us. This allows hardware specific
200 * ACPI implementations to determine its state.
201 */
get_attention_status(struct hotplug_slot * hotplug_slot,u8 * value)202 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
203 {
204 int retval = -EINVAL;
205
206 pr_debug("%s - physical_slot = %s\n", __func__,
207 hotplug_slot_name(hotplug_slot));
208
209 if (attention_info && try_module_get(attention_info->owner)) {
210 retval = attention_info->get_attn(hotplug_slot, value);
211 module_put(attention_info->owner);
212 } else
213 attention_info = NULL;
214 return retval;
215 }
216
217
218 /**
219 * get_latch_status - get latch status of a slot
220 * @hotplug_slot: slot to get status
221 * @value: pointer to store status
222 *
223 * ACPI doesn't provide any formal means to access latch status.
224 * Instead, we fake latch status from _STA.
225 */
get_latch_status(struct hotplug_slot * hotplug_slot,u8 * value)226 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
227 {
228 struct slot *slot = to_slot(hotplug_slot);
229
230 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
231
232 *value = acpiphp_get_latch_status(slot->acpi_slot);
233
234 return 0;
235 }
236
237
238 /**
239 * get_adapter_status - get adapter status of a slot
240 * @hotplug_slot: slot to get status
241 * @value: pointer to store status
242 *
243 * ACPI doesn't provide any formal means to access adapter status.
244 * Instead, we fake adapter status from _STA.
245 */
get_adapter_status(struct hotplug_slot * hotplug_slot,u8 * value)246 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
247 {
248 struct slot *slot = to_slot(hotplug_slot);
249
250 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
251
252 *value = acpiphp_get_adapter_status(slot->acpi_slot);
253
254 return 0;
255 }
256
257 /* callback routine to initialize 'struct slot' for each slot */
acpiphp_register_hotplug_slot(struct acpiphp_slot * acpiphp_slot,unsigned int sun)258 int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot,
259 unsigned int sun)
260 {
261 struct slot *slot;
262 int retval = -ENOMEM;
263 char name[SLOT_NAME_SIZE];
264
265 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
266 if (!slot)
267 goto error;
268
269 slot->hotplug_slot.ops = &acpi_hotplug_slot_ops;
270
271 slot->acpi_slot = acpiphp_slot;
272
273 acpiphp_slot->slot = slot;
274 slot->sun = sun;
275 snprintf(name, SLOT_NAME_SIZE, "%u", sun);
276
277 retval = pci_hp_register(&slot->hotplug_slot, acpiphp_slot->bus,
278 acpiphp_slot->device, name);
279 if (retval == -EBUSY)
280 goto error_slot;
281 if (retval) {
282 pr_err("pci_hp_register failed with error %d\n", retval);
283 goto error_slot;
284 }
285
286 pr_info("Slot [%s] registered\n", slot_name(slot));
287
288 return 0;
289 error_slot:
290 kfree(slot);
291 error:
292 return retval;
293 }
294
295
acpiphp_unregister_hotplug_slot(struct acpiphp_slot * acpiphp_slot)296 void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
297 {
298 struct slot *slot = acpiphp_slot->slot;
299
300 pr_info("Slot [%s] unregistered\n", slot_name(slot));
301
302 pci_hp_deregister(&slot->hotplug_slot);
303 kfree(slot);
304 }
305
306
acpiphp_init(void)307 void __init acpiphp_init(void)
308 {
309 pr_info(DRIVER_DESC " version: " DRIVER_VERSION "%s\n",
310 acpiphp_disabled ? ", disabled by user; please report a bug"
311 : "");
312 }
313