xref: /openbmc/linux/drivers/acpi/ac.c (revision 1edd0337)
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 
31 MODULE_AUTHOR("Paul Diefenbaugh");
32 MODULE_DESCRIPTION("ACPI AC Adapter Driver");
33 MODULE_LICENSE("GPL");
34 
35 static int acpi_ac_add(struct acpi_device *device);
36 static void acpi_ac_remove(struct acpi_device *device);
37 static void acpi_ac_notify(struct acpi_device *device, u32 event);
38 
39 static const struct acpi_device_id ac_device_ids[] = {
40 	{"ACPI0003", 0},
41 	{"", 0},
42 };
43 MODULE_DEVICE_TABLE(acpi, ac_device_ids);
44 
45 #ifdef CONFIG_PM_SLEEP
46 static int acpi_ac_resume(struct device *dev);
47 #endif
48 static SIMPLE_DEV_PM_OPS(acpi_ac_pm, NULL, acpi_ac_resume);
49 
50 static int ac_sleep_before_get_state_ms;
51 static int ac_only;
52 
53 static struct acpi_driver acpi_ac_driver = {
54 	.name = "ac",
55 	.class = ACPI_AC_CLASS,
56 	.ids = ac_device_ids,
57 	.flags = ACPI_DRIVER_ALL_NOTIFY_EVENTS,
58 	.ops = {
59 		.add = acpi_ac_add,
60 		.remove = acpi_ac_remove,
61 		.notify = acpi_ac_notify,
62 		},
63 	.drv.pm = &acpi_ac_pm,
64 };
65 
66 struct acpi_ac {
67 	struct power_supply *charger;
68 	struct power_supply_desc charger_desc;
69 	struct acpi_device *device;
70 	unsigned long long state;
71 	struct notifier_block battery_nb;
72 };
73 
74 #define to_acpi_ac(x) power_supply_get_drvdata(x)
75 
76 /* AC Adapter Management */
77 static int acpi_ac_get_state(struct acpi_ac *ac)
78 {
79 	acpi_status status = AE_OK;
80 
81 	if (!ac)
82 		return -EINVAL;
83 
84 	if (ac_only) {
85 		ac->state = 1;
86 		return 0;
87 	}
88 
89 	status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL,
90 				       &ac->state);
91 	if (ACPI_FAILURE(status)) {
92 		acpi_handle_info(ac->device->handle,
93 				"Error reading AC Adapter state: %s\n",
94 				acpi_format_exception(status));
95 		ac->state = ACPI_AC_STATUS_UNKNOWN;
96 		return -ENODEV;
97 	}
98 
99 	return 0;
100 }
101 
102 /* sysfs I/F */
103 static int get_ac_property(struct power_supply *psy,
104 			   enum power_supply_property psp,
105 			   union power_supply_propval *val)
106 {
107 	struct acpi_ac *ac = to_acpi_ac(psy);
108 
109 	if (!ac)
110 		return -ENODEV;
111 
112 	if (acpi_ac_get_state(ac))
113 		return -ENODEV;
114 
115 	switch (psp) {
116 	case POWER_SUPPLY_PROP_ONLINE:
117 		val->intval = ac->state;
118 		break;
119 	default:
120 		return -EINVAL;
121 	}
122 
123 	return 0;
124 }
125 
126 static enum power_supply_property ac_props[] = {
127 	POWER_SUPPLY_PROP_ONLINE,
128 };
129 
130 /* Driver Model */
131 static void acpi_ac_notify(struct acpi_device *device, u32 event)
132 {
133 	struct acpi_ac *ac = acpi_driver_data(device);
134 
135 	if (!ac)
136 		return;
137 
138 	switch (event) {
139 	default:
140 		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
141 				  event);
142 		fallthrough;
143 	case ACPI_AC_NOTIFY_STATUS:
144 	case ACPI_NOTIFY_BUS_CHECK:
145 	case ACPI_NOTIFY_DEVICE_CHECK:
146 		/*
147 		 * A buggy BIOS may notify AC first and then sleep for
148 		 * a specific time before doing actual operations in the
149 		 * EC event handler (_Qxx). This will cause the AC state
150 		 * reported by the ACPI event to be incorrect, so wait for a
151 		 * specific time for the EC event handler to make progress.
152 		 */
153 		if (ac_sleep_before_get_state_ms > 0)
154 			msleep(ac_sleep_before_get_state_ms);
155 
156 		acpi_ac_get_state(ac);
157 		acpi_bus_generate_netlink_event(device->pnp.device_class,
158 						  dev_name(&device->dev), event,
159 						  (u32) ac->state);
160 		acpi_notifier_call_chain(device, event, (u32) ac->state);
161 		kobject_uevent(&ac->charger->dev.kobj, KOBJ_CHANGE);
162 	}
163 }
164 
165 static int acpi_ac_battery_notify(struct notifier_block *nb,
166 				  unsigned long action, void *data)
167 {
168 	struct acpi_ac *ac = container_of(nb, struct acpi_ac, battery_nb);
169 	struct acpi_bus_event *event = (struct acpi_bus_event *)data;
170 
171 	/*
172 	 * On HP Pavilion dv6-6179er AC status notifications aren't triggered
173 	 * when adapter is plugged/unplugged. However, battery status
174 	 * notifications are triggered when battery starts charging or
175 	 * discharging. Re-reading AC status triggers lost AC notifications,
176 	 * if AC status has changed.
177 	 */
178 	if (strcmp(event->device_class, ACPI_BATTERY_CLASS) == 0 &&
179 	    event->type == ACPI_BATTERY_NOTIFY_STATUS)
180 		acpi_ac_get_state(ac);
181 
182 	return NOTIFY_OK;
183 }
184 
185 static int __init thinkpad_e530_quirk(const struct dmi_system_id *d)
186 {
187 	ac_sleep_before_get_state_ms = 1000;
188 	return 0;
189 }
190 
191 static int __init ac_only_quirk(const struct dmi_system_id *d)
192 {
193 	ac_only = 1;
194 	return 0;
195 }
196 
197 /* Please keep this list alphabetically sorted */
198 static const struct dmi_system_id ac_dmi_table[]  __initconst = {
199 	{
200 		/* Kodlix GK45 returning incorrect state */
201 		.callback = ac_only_quirk,
202 		.matches = {
203 			DMI_MATCH(DMI_PRODUCT_NAME, "GK45"),
204 		},
205 	},
206 	{
207 		/* Lenovo Thinkpad e530, see comment in acpi_ac_notify() */
208 		.callback = thinkpad_e530_quirk,
209 		.matches = {
210 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
211 			DMI_MATCH(DMI_PRODUCT_NAME, "32597CG"),
212 		},
213 	},
214 	{},
215 };
216 
217 static int acpi_ac_add(struct acpi_device *device)
218 {
219 	struct power_supply_config psy_cfg = {};
220 	int result = 0;
221 	struct acpi_ac *ac = NULL;
222 
223 
224 	if (!device)
225 		return -EINVAL;
226 
227 	ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);
228 	if (!ac)
229 		return -ENOMEM;
230 
231 	ac->device = device;
232 	strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
233 	strcpy(acpi_device_class(device), ACPI_AC_CLASS);
234 	device->driver_data = ac;
235 
236 	result = acpi_ac_get_state(ac);
237 	if (result)
238 		goto end;
239 
240 	psy_cfg.drv_data = ac;
241 
242 	ac->charger_desc.name = acpi_device_bid(device);
243 	ac->charger_desc.type = POWER_SUPPLY_TYPE_MAINS;
244 	ac->charger_desc.properties = ac_props;
245 	ac->charger_desc.num_properties = ARRAY_SIZE(ac_props);
246 	ac->charger_desc.get_property = get_ac_property;
247 	ac->charger = power_supply_register(&ac->device->dev,
248 					    &ac->charger_desc, &psy_cfg);
249 	if (IS_ERR(ac->charger)) {
250 		result = PTR_ERR(ac->charger);
251 		goto end;
252 	}
253 
254 	pr_info("%s [%s] (%s)\n", acpi_device_name(device),
255 		acpi_device_bid(device), ac->state ? "on-line" : "off-line");
256 
257 	ac->battery_nb.notifier_call = acpi_ac_battery_notify;
258 	register_acpi_notifier(&ac->battery_nb);
259 end:
260 	if (result)
261 		kfree(ac);
262 
263 	return result;
264 }
265 
266 #ifdef CONFIG_PM_SLEEP
267 static int acpi_ac_resume(struct device *dev)
268 {
269 	struct acpi_ac *ac;
270 	unsigned int old_state;
271 
272 	if (!dev)
273 		return -EINVAL;
274 
275 	ac = acpi_driver_data(to_acpi_device(dev));
276 	if (!ac)
277 		return -EINVAL;
278 
279 	old_state = ac->state;
280 	if (acpi_ac_get_state(ac))
281 		return 0;
282 	if (old_state != ac->state)
283 		kobject_uevent(&ac->charger->dev.kobj, KOBJ_CHANGE);
284 
285 	return 0;
286 }
287 #else
288 #define acpi_ac_resume NULL
289 #endif
290 
291 static void acpi_ac_remove(struct acpi_device *device)
292 {
293 	struct acpi_ac *ac = NULL;
294 
295 	if (!device || !acpi_driver_data(device))
296 		return;
297 
298 	ac = acpi_driver_data(device);
299 
300 	power_supply_unregister(ac->charger);
301 	unregister_acpi_notifier(&ac->battery_nb);
302 
303 	kfree(ac);
304 }
305 
306 static int __init acpi_ac_init(void)
307 {
308 	int result;
309 
310 	if (acpi_disabled)
311 		return -ENODEV;
312 
313 	if (acpi_quirk_skip_acpi_ac_and_battery())
314 		return -ENODEV;
315 
316 	dmi_check_system(ac_dmi_table);
317 
318 	result = acpi_bus_register_driver(&acpi_ac_driver);
319 	if (result < 0)
320 		return -ENODEV;
321 
322 	return 0;
323 }
324 
325 static void __exit acpi_ac_exit(void)
326 {
327 	acpi_bus_unregister_driver(&acpi_ac_driver);
328 }
329 module_init(acpi_ac_init);
330 module_exit(acpi_ac_exit);
331