1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * acpi_ac.c - ACPI AC Adapter Driver (Revision: 27)
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 */
8
9#define pr_fmt(fmt) "ACPI: AC: " fmt
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/init.h>
15#include <linux/types.h>
16#include <linux/dmi.h>
17#include <linux/delay.h>
18#include <linux/platform_device.h>
19#include <linux/power_supply.h>
20#include <linux/string_choices.h>
21#include <linux/acpi.h>
22#include <acpi/battery.h>
23
24#define ACPI_AC_CLASS "ac_adapter"
25#define ACPI_AC_DEVICE_NAME "AC Adapter"
26#define ACPI_AC_FILE_STATE "state"
27#define ACPI_AC_NOTIFY_STATUS 0x80
28#define ACPI_AC_STATUS_OFFLINE 0x00
29#define ACPI_AC_STATUS_ONLINE 0x01
30#define ACPI_AC_STATUS_UNKNOWN 0xFF
31
32MODULE_AUTHOR("Paul Diefenbaugh");
33MODULE_DESCRIPTION("ACPI AC Adapter Driver");
34MODULE_LICENSE("GPL");
35
36static int acpi_ac_probe(struct platform_device *pdev);
37static void acpi_ac_remove(struct platform_device *pdev);
38
39static void acpi_ac_notify(acpi_handle handle, u32 event, void *data);
40
41static const struct acpi_device_id ac_device_ids[] = {
42 {"ACPI0003", 0},
43 {"", 0},
44};
45MODULE_DEVICE_TABLE(acpi, ac_device_ids);
46
47#ifdef CONFIG_PM_SLEEP
48static int acpi_ac_resume(struct device *dev);
49#endif
50static SIMPLE_DEV_PM_OPS(acpi_ac_pm, NULL, acpi_ac_resume);
51
52static int ac_sleep_before_get_state_ms;
53static int ac_only;
54
55struct acpi_ac {
56 struct power_supply *charger;
57 struct power_supply_desc charger_desc;
58 struct acpi_device *device;
59 unsigned long long state;
60 struct notifier_block battery_nb;
61};
62
63#define to_acpi_ac(x) power_supply_get_drvdata(x)
64
65/* AC Adapter Management */
66static int acpi_ac_get_state(struct acpi_ac *ac)
67{
68 acpi_status status = AE_OK;
69
70 if (!ac)
71 return -EINVAL;
72
73 if (ac_only) {
74 ac->state = 1;
75 return 0;
76 }
77
78 status = acpi_evaluate_integer(handle: ac->device->handle, pathname: "_PSR", NULL,
79 data: &ac->state);
80 if (ACPI_FAILURE(status)) {
81 acpi_handle_info(ac->device->handle,
82 "Error reading AC Adapter state: %s\n",
83 acpi_format_exception(status));
84 ac->state = ACPI_AC_STATUS_UNKNOWN;
85 return -ENODEV;
86 }
87
88 return 0;
89}
90
91/* sysfs I/F */
92static int get_ac_property(struct power_supply *psy,
93 enum power_supply_property psp,
94 union power_supply_propval *val)
95{
96 struct acpi_ac *ac = to_acpi_ac(psy);
97
98 if (!ac)
99 return -ENODEV;
100
101 if (acpi_ac_get_state(ac))
102 return -ENODEV;
103
104 switch (psp) {
105 case POWER_SUPPLY_PROP_ONLINE:
106 val->intval = ac->state;
107 break;
108 default:
109 return -EINVAL;
110 }
111
112 return 0;
113}
114
115static enum power_supply_property ac_props[] = {
116 POWER_SUPPLY_PROP_ONLINE,
117};
118
119/* Driver Model */
120static void acpi_ac_notify(acpi_handle handle, u32 event, void *data)
121{
122 struct acpi_ac *ac = data;
123 struct acpi_device *adev = ac->device;
124
125 switch (event) {
126 default:
127 acpi_handle_debug(adev->handle, "Unsupported event [0x%x]\n",
128 event);
129 fallthrough;
130 case ACPI_AC_NOTIFY_STATUS:
131 case ACPI_NOTIFY_BUS_CHECK:
132 case ACPI_NOTIFY_DEVICE_CHECK:
133 /*
134 * A buggy BIOS may notify AC first and then sleep for
135 * a specific time before doing actual operations in the
136 * EC event handler (_Qxx). This will cause the AC state
137 * reported by the ACPI event to be incorrect, so wait for a
138 * specific time for the EC event handler to make progress.
139 */
140 if (ac_sleep_before_get_state_ms > 0)
141 msleep(msecs: ac_sleep_before_get_state_ms);
142
143 acpi_ac_get_state(ac);
144 acpi_bus_generate_netlink_event(adev->pnp.device_class,
145 dev_name(dev: &adev->dev), event,
146 (u32) ac->state);
147 acpi_notifier_call_chain(adev, event, (u32) ac->state);
148 kobject_uevent(kobj: &ac->charger->dev.kobj, action: KOBJ_CHANGE);
149 }
150}
151
152static int acpi_ac_battery_notify(struct notifier_block *nb,
153 unsigned long action, void *data)
154{
155 struct acpi_ac *ac = container_of(nb, struct acpi_ac, battery_nb);
156 struct acpi_bus_event *event = (struct acpi_bus_event *)data;
157
158 /*
159 * On HP Pavilion dv6-6179er AC status notifications aren't triggered
160 * when adapter is plugged/unplugged. However, battery status
161 * notifications are triggered when battery starts charging or
162 * discharging. Re-reading AC status triggers lost AC notifications,
163 * if AC status has changed.
164 */
165 if (strcmp(event->device_class, ACPI_BATTERY_CLASS) == 0 &&
166 event->type == ACPI_BATTERY_NOTIFY_STATUS)
167 acpi_ac_get_state(ac);
168
169 return NOTIFY_OK;
170}
171
172static int __init thinkpad_e530_quirk(const struct dmi_system_id *d)
173{
174 ac_sleep_before_get_state_ms = 1000;
175 return 0;
176}
177
178static int __init ac_only_quirk(const struct dmi_system_id *d)
179{
180 ac_only = 1;
181 return 0;
182}
183
184/* Please keep this list alphabetically sorted */
185static const struct dmi_system_id ac_dmi_table[] __initconst = {
186 {
187 /* Kodlix GK45 returning incorrect state */
188 .callback = ac_only_quirk,
189 .matches = {
190 DMI_MATCH(DMI_PRODUCT_NAME, "GK45"),
191 },
192 },
193 {
194 /* Lenovo Thinkpad e530, see comment in acpi_ac_notify() */
195 .callback = thinkpad_e530_quirk,
196 .matches = {
197 DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
198 DMI_MATCH(DMI_PRODUCT_NAME, "32597CG"),
199 },
200 },
201 {},
202};
203
204static int acpi_ac_probe(struct platform_device *pdev)
205{
206 struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
207 struct power_supply_config psy_cfg = {};
208 struct acpi_ac *ac;
209 int result;
210
211 ac = kzalloc(size: sizeof(struct acpi_ac), GFP_KERNEL);
212 if (!ac)
213 return -ENOMEM;
214
215 ac->device = adev;
216 strcpy(acpi_device_name(adev), ACPI_AC_DEVICE_NAME);
217 strcpy(acpi_device_class(adev), ACPI_AC_CLASS);
218
219 platform_set_drvdata(pdev, data: ac);
220
221 result = acpi_ac_get_state(ac);
222 if (result)
223 goto err_release_ac;
224
225 psy_cfg.drv_data = ac;
226
227 ac->charger_desc.name = acpi_device_bid(adev);
228 ac->charger_desc.type = POWER_SUPPLY_TYPE_MAINS;
229 ac->charger_desc.properties = ac_props;
230 ac->charger_desc.num_properties = ARRAY_SIZE(ac_props);
231 ac->charger_desc.get_property = get_ac_property;
232 ac->charger = power_supply_register(parent: &pdev->dev,
233 desc: &ac->charger_desc, cfg: &psy_cfg);
234 if (IS_ERR(ptr: ac->charger)) {
235 result = PTR_ERR(ptr: ac->charger);
236 goto err_release_ac;
237 }
238
239 pr_info("%s [%s] (%s-line)\n", acpi_device_name(adev),
240 acpi_device_bid(adev), str_on_off(ac->state));
241
242 ac->battery_nb.notifier_call = acpi_ac_battery_notify;
243 register_acpi_notifier(&ac->battery_nb);
244
245 result = acpi_dev_install_notify_handler(adev, ACPI_ALL_NOTIFY,
246 handler: acpi_ac_notify, context: ac);
247 if (result)
248 goto err_unregister;
249
250 return 0;
251
252err_unregister:
253 power_supply_unregister(psy: ac->charger);
254 unregister_acpi_notifier(&ac->battery_nb);
255err_release_ac:
256 kfree(objp: ac);
257
258 return result;
259}
260
261#ifdef CONFIG_PM_SLEEP
262static int acpi_ac_resume(struct device *dev)
263{
264 struct acpi_ac *ac = dev_get_drvdata(dev);
265 unsigned int old_state;
266
267 old_state = ac->state;
268 if (acpi_ac_get_state(ac))
269 return 0;
270 if (old_state != ac->state)
271 kobject_uevent(kobj: &ac->charger->dev.kobj, action: KOBJ_CHANGE);
272
273 return 0;
274}
275#else
276#define acpi_ac_resume NULL
277#endif
278
279static void acpi_ac_remove(struct platform_device *pdev)
280{
281 struct acpi_ac *ac = platform_get_drvdata(pdev);
282
283 acpi_dev_remove_notify_handler(adev: ac->device, ACPI_ALL_NOTIFY,
284 handler: acpi_ac_notify);
285 power_supply_unregister(psy: ac->charger);
286 unregister_acpi_notifier(&ac->battery_nb);
287
288 kfree(objp: ac);
289}
290
291static struct platform_driver acpi_ac_driver = {
292 .probe = acpi_ac_probe,
293 .remove_new = acpi_ac_remove,
294 .driver = {
295 .name = "ac",
296 .acpi_match_table = ac_device_ids,
297 .pm = &acpi_ac_pm,
298 },
299};
300
301static int __init acpi_ac_init(void)
302{
303 int result;
304
305 if (acpi_disabled)
306 return -ENODEV;
307
308 if (acpi_quirk_skip_acpi_ac_and_battery())
309 return -ENODEV;
310
311 dmi_check_system(list: ac_dmi_table);
312
313 result = platform_driver_register(&acpi_ac_driver);
314 if (result < 0)
315 return -ENODEV;
316
317 return 0;
318}
319
320static void __exit acpi_ac_exit(void)
321{
322 platform_driver_unregister(&acpi_ac_driver);
323}
324module_init(acpi_ac_init);
325module_exit(acpi_ac_exit);
326

source code of linux/drivers/acpi/ac.c