xref: /linux/drivers/acpi/ac.c (revision ebc733e54a1a79ea2dde2ba5121ae73a188e20d4)
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 
32 MODULE_AUTHOR("Paul Diefenbaugh");
33 MODULE_DESCRIPTION("ACPI AC Adapter Driver");
34 MODULE_LICENSE("GPL");
35 
36 static int acpi_ac_probe(struct platform_device *pdev);
37 static void acpi_ac_remove(struct platform_device *pdev);
38 
39 static void acpi_ac_notify(acpi_handle handle, u32 event, void *data);
40 
41 static const struct acpi_device_id ac_device_ids[] = {
42 	{"ACPI0003", 0},
43 	{"", 0},
44 };
45 MODULE_DEVICE_TABLE(acpi, ac_device_ids);
46 
47 #ifdef CONFIG_PM_SLEEP
48 static int acpi_ac_resume(struct device *dev);
49 #endif
50 static SIMPLE_DEV_PM_OPS(acpi_ac_pm, NULL, acpi_ac_resume);
51 
52 static int ac_sleep_before_get_state_ms;
53 static int ac_only;
54 
55 struct 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 */
66 static 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 */
92 static 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 
115 static enum power_supply_property ac_props[] = {
116 	POWER_SUPPLY_PROP_ONLINE,
117 };
118 
119 /* Driver Model */
120 static 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 
152 static 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 
172 static 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 
178 static 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 */
185 static 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 
204 static 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 
252 err_unregister:
253 	power_supply_unregister(ac->charger);
254 	unregister_acpi_notifier(&ac->battery_nb);
255 err_release_ac:
256 	kfree(ac);
257 
258 	return result;
259 }
260 
261 #ifdef CONFIG_PM_SLEEP
262 static 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 
279 static 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 
291 static 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 
301 static 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 
320 static void __exit acpi_ac_exit(void)
321 {
322 	platform_driver_unregister(&acpi_ac_driver);
323 }
324 module_init(acpi_ac_init);
325 module_exit(acpi_ac_exit);
326