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(ac->device->handle, "_PSR", NULL,
79				       &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(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(&adev->dev), event,
146						  (u32) ac->state);
147		acpi_notifier_call_chain(adev, event, (u32) ac->state);
148		kobject_uevent(&ac->charger->dev.kobj, 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(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, 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(&pdev->dev,
233					    &ac->charger_desc, &psy_cfg);
234	if (IS_ERR(ac->charger)) {
235		result = PTR_ERR(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						 acpi_ac_notify, ac);
247	if (result)
248		goto err_unregister;
249
250	return 0;
251
252err_unregister:
253	power_supply_unregister(ac->charger);
254	unregister_acpi_notifier(&ac->battery_nb);
255err_release_ac:
256	kfree(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(&ac->charger->dev.kobj, 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(ac->device, ACPI_ALL_NOTIFY,
284				       acpi_ac_notify);
285	power_supply_unregister(ac->charger);
286	unregister_acpi_notifier(&ac->battery_nb);
287
288	kfree(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(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