xref: /kernel/linux/linux-6.6/drivers/acpi/ac.c (revision 62306a36) 
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/acpi.h>
21#include <acpi/battery.h>
22
23#define ACPI_AC_CLASS			"ac_adapter"
24#define ACPI_AC_DEVICE_NAME		"AC Adapter"
25#define ACPI_AC_FILE_STATE		"state"
26#define ACPI_AC_NOTIFY_STATUS		0x80
27#define ACPI_AC_STATUS_OFFLINE		0x00
28#define ACPI_AC_STATUS_ONLINE		0x01
29#define ACPI_AC_STATUS_UNKNOWN		0xFF
30
31MODULE_AUTHOR("Paul Diefenbaugh");
32MODULE_DESCRIPTION("ACPI AC Adapter Driver");
33MODULE_LICENSE("GPL");
34
35static int acpi_ac_add(struct acpi_device *device);
36static void acpi_ac_remove(struct acpi_device *device);
37static void acpi_ac_notify(acpi_handle handle, u32 event, void *data);
38
39static const struct acpi_device_id ac_device_ids[] = {
40	{"ACPI0003", 0},
41	{"", 0},
42};
43MODULE_DEVICE_TABLE(acpi, ac_device_ids);
44
45#ifdef CONFIG_PM_SLEEP
46static int acpi_ac_resume(struct device *dev);
47#endif
48static SIMPLE_DEV_PM_OPS(acpi_ac_pm, NULL, acpi_ac_resume);
49
50static int ac_sleep_before_get_state_ms;
51static int ac_only;
52
53static struct acpi_driver acpi_ac_driver = {
54	.name = "ac",
55	.class = ACPI_AC_CLASS,
56	.ids = ac_device_ids,
57	.ops = {
58		.add = acpi_ac_add,
59		.remove = acpi_ac_remove,
60		},
61	.drv.pm = &acpi_ac_pm,
62};
63
64struct acpi_ac {
65	struct power_supply *charger;
66	struct power_supply_desc charger_desc;
67	struct acpi_device *device;
68	unsigned long long state;
69	struct notifier_block battery_nb;
70};
71
72#define to_acpi_ac(x) power_supply_get_drvdata(x)
73
74/* AC Adapter Management */
75static int acpi_ac_get_state(struct acpi_ac *ac)
76{
77	acpi_status status = AE_OK;
78
79	if (!ac)
80		return -EINVAL;
81
82	if (ac_only) {
83		ac->state = 1;
84		return 0;
85	}
86
87	status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL,
88				       &ac->state);
89	if (ACPI_FAILURE(status)) {
90		acpi_handle_info(ac->device->handle,
91				"Error reading AC Adapter state: %s\n",
92				acpi_format_exception(status));
93		ac->state = ACPI_AC_STATUS_UNKNOWN;
94		return -ENODEV;
95	}
96
97	return 0;
98}
99
100/* sysfs I/F */
101static int get_ac_property(struct power_supply *psy,
102			   enum power_supply_property psp,
103			   union power_supply_propval *val)
104{
105	struct acpi_ac *ac = to_acpi_ac(psy);
106
107	if (!ac)
108		return -ENODEV;
109
110	if (acpi_ac_get_state(ac))
111		return -ENODEV;
112
113	switch (psp) {
114	case POWER_SUPPLY_PROP_ONLINE:
115		val->intval = ac->state;
116		break;
117	default:
118		return -EINVAL;
119	}
120
121	return 0;
122}
123
124static enum power_supply_property ac_props[] = {
125	POWER_SUPPLY_PROP_ONLINE,
126};
127
128/* Driver Model */
129static void acpi_ac_notify(acpi_handle handle, u32 event, void *data)
130{
131	struct acpi_device *device = data;
132	struct acpi_ac *ac = acpi_driver_data(device);
133
134	if (!ac)
135		return;
136
137	switch (event) {
138	default:
139		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
140				  event);
141		fallthrough;
142	case ACPI_AC_NOTIFY_STATUS:
143	case ACPI_NOTIFY_BUS_CHECK:
144	case ACPI_NOTIFY_DEVICE_CHECK:
145		/*
146		 * A buggy BIOS may notify AC first and then sleep for
147		 * a specific time before doing actual operations in the
148		 * EC event handler (_Qxx). This will cause the AC state
149		 * reported by the ACPI event to be incorrect, so wait for a
150		 * specific time for the EC event handler to make progress.
151		 */
152		if (ac_sleep_before_get_state_ms > 0)
153			msleep(ac_sleep_before_get_state_ms);
154
155		acpi_ac_get_state(ac);
156		acpi_bus_generate_netlink_event(device->pnp.device_class,
157						  dev_name(&device->dev), event,
158						  (u32) ac->state);
159		acpi_notifier_call_chain(device, event, (u32) ac->state);
160		kobject_uevent(&ac->charger->dev.kobj, KOBJ_CHANGE);
161	}
162}
163
164static int acpi_ac_battery_notify(struct notifier_block *nb,
165				  unsigned long action, void *data)
166{
167	struct acpi_ac *ac = container_of(nb, struct acpi_ac, battery_nb);
168	struct acpi_bus_event *event = (struct acpi_bus_event *)data;
169
170	/*
171	 * On HP Pavilion dv6-6179er AC status notifications aren't triggered
172	 * when adapter is plugged/unplugged. However, battery status
173	 * notifications are triggered when battery starts charging or
174	 * discharging. Re-reading AC status triggers lost AC notifications,
175	 * if AC status has changed.
176	 */
177	if (strcmp(event->device_class, ACPI_BATTERY_CLASS) == 0 &&
178	    event->type == ACPI_BATTERY_NOTIFY_STATUS)
179		acpi_ac_get_state(ac);
180
181	return NOTIFY_OK;
182}
183
184static int __init thinkpad_e530_quirk(const struct dmi_system_id *d)
185{
186	ac_sleep_before_get_state_ms = 1000;
187	return 0;
188}
189
190static int __init ac_only_quirk(const struct dmi_system_id *d)
191{
192	ac_only = 1;
193	return 0;
194}
195
196/* Please keep this list alphabetically sorted */
197static const struct dmi_system_id ac_dmi_table[]  __initconst = {
198	{
199		/* Kodlix GK45 returning incorrect state */
200		.callback = ac_only_quirk,
201		.matches = {
202			DMI_MATCH(DMI_PRODUCT_NAME, "GK45"),
203		},
204	},
205	{
206		/* Lenovo Thinkpad e530, see comment in acpi_ac_notify() */
207		.callback = thinkpad_e530_quirk,
208		.matches = {
209			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
210			DMI_MATCH(DMI_PRODUCT_NAME, "32597CG"),
211		},
212	},
213	{},
214};
215
216static int acpi_ac_add(struct acpi_device *device)
217{
218	struct power_supply_config psy_cfg = {};
219	int result = 0;
220	struct acpi_ac *ac = NULL;
221
222
223	if (!device)
224		return -EINVAL;
225
226	ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);
227	if (!ac)
228		return -ENOMEM;
229
230	ac->device = device;
231	strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
232	strcpy(acpi_device_class(device), ACPI_AC_CLASS);
233	device->driver_data = ac;
234
235	result = acpi_ac_get_state(ac);
236	if (result)
237		goto err_release_ac;
238
239	psy_cfg.drv_data = ac;
240
241	ac->charger_desc.name = acpi_device_bid(device);
242	ac->charger_desc.type = POWER_SUPPLY_TYPE_MAINS;
243	ac->charger_desc.properties = ac_props;
244	ac->charger_desc.num_properties = ARRAY_SIZE(ac_props);
245	ac->charger_desc.get_property = get_ac_property;
246	ac->charger = power_supply_register(&ac->device->dev,
247					    &ac->charger_desc, &psy_cfg);
248	if (IS_ERR(ac->charger)) {
249		result = PTR_ERR(ac->charger);
250		goto err_release_ac;
251	}
252
253	pr_info("%s [%s] (%s)\n", acpi_device_name(device),
254		acpi_device_bid(device), ac->state ? "on-line" : "off-line");
255
256	ac->battery_nb.notifier_call = acpi_ac_battery_notify;
257	register_acpi_notifier(&ac->battery_nb);
258
259	result = acpi_dev_install_notify_handler(device, ACPI_ALL_NOTIFY,
260						 acpi_ac_notify);
261	if (result)
262		goto err_unregister;
263
264	return 0;
265
266err_unregister:
267	power_supply_unregister(ac->charger);
268	unregister_acpi_notifier(&ac->battery_nb);
269err_release_ac:
270	kfree(ac);
271
272	return result;
273}
274
275#ifdef CONFIG_PM_SLEEP
276static int acpi_ac_resume(struct device *dev)
277{
278	struct acpi_ac *ac;
279	unsigned int old_state;
280
281	if (!dev)
282		return -EINVAL;
283
284	ac = acpi_driver_data(to_acpi_device(dev));
285	if (!ac)
286		return -EINVAL;
287
288	old_state = ac->state;
289	if (acpi_ac_get_state(ac))
290		return 0;
291	if (old_state != ac->state)
292		kobject_uevent(&ac->charger->dev.kobj, KOBJ_CHANGE);
293
294	return 0;
295}
296#else
297#define acpi_ac_resume NULL
298#endif
299
300static void acpi_ac_remove(struct acpi_device *device)
301{
302	struct acpi_ac *ac = NULL;
303
304	if (!device || !acpi_driver_data(device))
305		return;
306
307	ac = acpi_driver_data(device);
308
309	acpi_dev_remove_notify_handler(device, ACPI_ALL_NOTIFY,
310				       acpi_ac_notify);
311	power_supply_unregister(ac->charger);
312	unregister_acpi_notifier(&ac->battery_nb);
313
314	kfree(ac);
315}
316
317static int __init acpi_ac_init(void)
318{
319	int result;
320
321	if (acpi_disabled)
322		return -ENODEV;
323
324	if (acpi_quirk_skip_acpi_ac_and_battery())
325		return -ENODEV;
326
327	dmi_check_system(ac_dmi_table);
328
329	result = acpi_bus_register_driver(&acpi_ac_driver);
330	if (result < 0)
331		return -ENODEV;
332
333	return 0;
334}
335
336static void __exit acpi_ac_exit(void)
337{
338	acpi_bus_unregister_driver(&acpi_ac_driver);
339}
340module_init(acpi_ac_init);
341module_exit(acpi_ac_exit);
342