xref: /openbmc/linux/drivers/pnp/pnpacpi/core.c (revision 3ddc8b84)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * pnpacpi -- PnP ACPI driver
4  *
5  * Copyright (c) 2004 Matthieu Castet <castet.matthieu@free.fr>
6  * Copyright (c) 2004 Li Shaohua <shaohua.li@intel.com>
7  */
8 
9 #include <linux/export.h>
10 #include <linux/acpi.h>
11 #include <linux/pnp.h>
12 #include <linux/slab.h>
13 #include <linux/mod_devicetable.h>
14 
15 #include "../base.h"
16 #include "pnpacpi.h"
17 
18 static int num;
19 
20 /*
21  * Compatible Device IDs
22  */
23 #define TEST_HEX(c) \
24 	if (!(('0' <= (c) && (c) <= '9') || ('A' <= (c) && (c) <= 'F'))) \
25 		return 0
26 #define TEST_ALPHA(c) \
27 	if (!('A' <= (c) && (c) <= 'Z')) \
28 		return 0
29 static int __init ispnpidacpi(const char *id)
30 {
31 	TEST_ALPHA(id[0]);
32 	TEST_ALPHA(id[1]);
33 	TEST_ALPHA(id[2]);
34 	TEST_HEX(id[3]);
35 	TEST_HEX(id[4]);
36 	TEST_HEX(id[5]);
37 	TEST_HEX(id[6]);
38 	if (id[7] != '\0')
39 		return 0;
40 	return 1;
41 }
42 
43 static int pnpacpi_get_resources(struct pnp_dev *dev)
44 {
45 	pnp_dbg(&dev->dev, "get resources\n");
46 	return pnpacpi_parse_allocated_resource(dev);
47 }
48 
49 static int pnpacpi_set_resources(struct pnp_dev *dev)
50 {
51 	struct acpi_device *acpi_dev;
52 	acpi_handle handle;
53 	int ret = 0;
54 
55 	pnp_dbg(&dev->dev, "set resources\n");
56 
57 	acpi_dev = ACPI_COMPANION(&dev->dev);
58 	if (!acpi_dev) {
59 		dev_dbg(&dev->dev, "ACPI device not found in %s!\n", __func__);
60 		return -ENODEV;
61 	}
62 
63 	if (WARN_ON_ONCE(acpi_dev != dev->data))
64 		dev->data = acpi_dev;
65 
66 	handle = acpi_dev->handle;
67 	if (acpi_has_method(handle, METHOD_NAME__SRS)) {
68 		struct acpi_buffer buffer;
69 
70 		ret = pnpacpi_build_resource_template(dev, &buffer);
71 		if (ret)
72 			return ret;
73 
74 		ret = pnpacpi_encode_resources(dev, &buffer);
75 		if (!ret) {
76 			acpi_status status;
77 
78 			status = acpi_set_current_resources(handle, &buffer);
79 			if (ACPI_FAILURE(status))
80 				ret = -EIO;
81 		}
82 		kfree(buffer.pointer);
83 	}
84 	if (!ret && acpi_device_power_manageable(acpi_dev))
85 		ret = acpi_device_set_power(acpi_dev, ACPI_STATE_D0);
86 
87 	return ret;
88 }
89 
90 static int pnpacpi_disable_resources(struct pnp_dev *dev)
91 {
92 	struct acpi_device *acpi_dev;
93 	acpi_status status;
94 
95 	dev_dbg(&dev->dev, "disable resources\n");
96 
97 	acpi_dev = ACPI_COMPANION(&dev->dev);
98 	if (!acpi_dev) {
99 		dev_dbg(&dev->dev, "ACPI device not found in %s!\n", __func__);
100 		return 0;
101 	}
102 
103 	/* acpi_unregister_gsi(pnp_irq(dev, 0)); */
104 	if (acpi_device_power_manageable(acpi_dev))
105 		acpi_device_set_power(acpi_dev, ACPI_STATE_D3_COLD);
106 
107 	/* continue even if acpi_device_set_power() fails */
108 	status = acpi_evaluate_object(acpi_dev->handle, "_DIS", NULL, NULL);
109 	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
110 		return -ENODEV;
111 
112 	return 0;
113 }
114 
115 #ifdef CONFIG_ACPI_SLEEP
116 static bool pnpacpi_can_wakeup(struct pnp_dev *dev)
117 {
118 	struct acpi_device *acpi_dev = ACPI_COMPANION(&dev->dev);
119 
120 	if (!acpi_dev) {
121 		dev_dbg(&dev->dev, "ACPI device not found in %s!\n", __func__);
122 		return false;
123 	}
124 
125 	return acpi_bus_can_wakeup(acpi_dev->handle);
126 }
127 
128 static int pnpacpi_suspend(struct pnp_dev *dev, pm_message_t state)
129 {
130 	struct acpi_device *acpi_dev = ACPI_COMPANION(&dev->dev);
131 	int error = 0;
132 
133 	if (!acpi_dev) {
134 		dev_dbg(&dev->dev, "ACPI device not found in %s!\n", __func__);
135 		return 0;
136 	}
137 
138 	if (device_can_wakeup(&dev->dev)) {
139 		error = acpi_pm_set_device_wakeup(&dev->dev,
140 					      device_may_wakeup(&dev->dev));
141 		if (error)
142 			return error;
143 	}
144 
145 	if (acpi_device_power_manageable(acpi_dev)) {
146 		int power_state = acpi_pm_device_sleep_state(&dev->dev, NULL,
147 							ACPI_STATE_D3_COLD);
148 		if (power_state < 0)
149 			power_state = (state.event == PM_EVENT_ON) ?
150 					ACPI_STATE_D0 : ACPI_STATE_D3_COLD;
151 
152 		/*
153 		 * acpi_device_set_power() can fail (keyboard port can't be
154 		 * powered-down?), and in any case, our return value is ignored
155 		 * by pnp_bus_suspend().  Hence we don't revert the wakeup
156 		 * setting if the set_power fails.
157 		 */
158 		error = acpi_device_set_power(acpi_dev, power_state);
159 	}
160 
161 	return error;
162 }
163 
164 static int pnpacpi_resume(struct pnp_dev *dev)
165 {
166 	struct acpi_device *acpi_dev = ACPI_COMPANION(&dev->dev);
167 	int error = 0;
168 
169 	if (!acpi_dev) {
170 		dev_dbg(&dev->dev, "ACPI device not found in %s!\n", __func__);
171 		return -ENODEV;
172 	}
173 
174 	if (device_may_wakeup(&dev->dev))
175 		acpi_pm_set_device_wakeup(&dev->dev, false);
176 
177 	if (acpi_device_power_manageable(acpi_dev))
178 		error = acpi_device_set_power(acpi_dev, ACPI_STATE_D0);
179 
180 	return error;
181 }
182 #endif
183 
184 struct pnp_protocol pnpacpi_protocol = {
185 	.name	 = "Plug and Play ACPI",
186 	.get	 = pnpacpi_get_resources,
187 	.set	 = pnpacpi_set_resources,
188 	.disable = pnpacpi_disable_resources,
189 #ifdef CONFIG_ACPI_SLEEP
190 	.can_wakeup = pnpacpi_can_wakeup,
191 	.suspend = pnpacpi_suspend,
192 	.resume = pnpacpi_resume,
193 #endif
194 };
195 EXPORT_SYMBOL(pnpacpi_protocol);
196 
197 static const char *__init pnpacpi_get_id(struct acpi_device *device)
198 {
199 	struct acpi_hardware_id *id;
200 
201 	list_for_each_entry(id, &device->pnp.ids, list) {
202 		if (ispnpidacpi(id->id))
203 			return id->id;
204 	}
205 
206 	return NULL;
207 }
208 
209 static int __init pnpacpi_add_device(struct acpi_device *device)
210 {
211 	struct pnp_dev *dev;
212 	const char *pnpid;
213 	struct acpi_hardware_id *id;
214 	int error;
215 
216 	/* Skip devices that are already bound */
217 	if (device->physical_node_count)
218 		return 0;
219 
220 	/*
221 	 * If a PnPacpi device is not present , the device
222 	 * driver should not be loaded.
223 	 */
224 	if (!acpi_has_method(device->handle, "_CRS"))
225 		return 0;
226 
227 	pnpid = pnpacpi_get_id(device);
228 	if (!pnpid)
229 		return 0;
230 
231 	if (!device->status.present)
232 		return 0;
233 
234 	dev = pnp_alloc_dev(&pnpacpi_protocol, num, pnpid);
235 	if (!dev)
236 		return -ENOMEM;
237 
238 	ACPI_COMPANION_SET(&dev->dev, device);
239 	dev->data = device;
240 	/* .enabled means the device can decode the resources */
241 	dev->active = device->status.enabled;
242 	if (acpi_has_method(device->handle, "_SRS"))
243 		dev->capabilities |= PNP_CONFIGURABLE;
244 	dev->capabilities |= PNP_READ;
245 	if (device->flags.dynamic_status && (dev->capabilities & PNP_CONFIGURABLE))
246 		dev->capabilities |= PNP_WRITE;
247 	if (device->flags.removable)
248 		dev->capabilities |= PNP_REMOVABLE;
249 	if (acpi_has_method(device->handle, "_DIS"))
250 		dev->capabilities |= PNP_DISABLE;
251 
252 	if (strlen(acpi_device_name(device)))
253 		strncpy(dev->name, acpi_device_name(device), sizeof(dev->name));
254 	else
255 		strncpy(dev->name, acpi_device_bid(device), sizeof(dev->name));
256 
257 	/* Handle possible string truncation */
258 	dev->name[sizeof(dev->name) - 1] = '\0';
259 
260 	if (dev->active)
261 		pnpacpi_parse_allocated_resource(dev);
262 
263 	if (dev->capabilities & PNP_CONFIGURABLE)
264 		pnpacpi_parse_resource_option_data(dev);
265 
266 	list_for_each_entry(id, &device->pnp.ids, list) {
267 		if (!strcmp(id->id, pnpid))
268 			continue;
269 		if (!ispnpidacpi(id->id))
270 			continue;
271 		pnp_add_id(dev, id->id);
272 	}
273 
274 	/* clear out the damaged flags */
275 	if (!dev->active)
276 		pnp_init_resources(dev);
277 
278 	error = pnp_add_device(dev);
279 	if (error) {
280 		put_device(&dev->dev);
281 		return error;
282 	}
283 
284 	num++;
285 
286 	return 0;
287 }
288 
289 static acpi_status __init pnpacpi_add_device_handler(acpi_handle handle,
290 						     u32 lvl, void *context,
291 						     void **rv)
292 {
293 	struct acpi_device *device = acpi_fetch_acpi_dev(handle);
294 
295 	if (!device)
296 		return AE_CTRL_DEPTH;
297 	if (acpi_is_pnp_device(device))
298 		pnpacpi_add_device(device);
299 	return AE_OK;
300 }
301 
302 int pnpacpi_disabled __initdata;
303 static int __init pnpacpi_init(void)
304 {
305 	if (acpi_disabled || pnpacpi_disabled) {
306 		printk(KERN_INFO "pnp: PnP ACPI: disabled\n");
307 		return 0;
308 	}
309 	printk(KERN_INFO "pnp: PnP ACPI init\n");
310 	pnp_register_protocol(&pnpacpi_protocol);
311 	acpi_get_devices(NULL, pnpacpi_add_device_handler, NULL, NULL);
312 	printk(KERN_INFO "pnp: PnP ACPI: found %d devices\n", num);
313 	pnp_platform_devices = 1;
314 	return 0;
315 }
316 
317 fs_initcall(pnpacpi_init);
318 
319 static int __init pnpacpi_setup(char *str)
320 {
321 	if (str == NULL)
322 		return 1;
323 	if (!strncmp(str, "off", 3))
324 		pnpacpi_disabled = 1;
325 	return 1;
326 }
327 
328 __setup("pnpacpi=", pnpacpi_setup);
329