1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  HP Compaq TC1100 Tablet WMI Extras Driver
4  *
5  *  Copyright (C) 2007 Carlos Corbacho <carlos@strangeworlds.co.uk>
6  *  Copyright (C) 2004 Jamey Hicks <jamey.hicks@hp.com>
7  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
8  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
9  */
10 
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/slab.h>
16 #include <linux/init.h>
17 #include <linux/types.h>
18 #include <linux/acpi.h>
19 #include <linux/platform_device.h>
20 
21 #define GUID "C364AC71-36DB-495A-8494-B439D472A505"
22 
23 #define TC1100_INSTANCE_WIRELESS		1
24 #define TC1100_INSTANCE_JOGDIAL		2
25 
26 MODULE_AUTHOR("Jamey Hicks, Carlos Corbacho");
27 MODULE_DESCRIPTION("HP Compaq TC1100 Tablet WMI Extras");
28 MODULE_LICENSE("GPL");
29 MODULE_ALIAS("wmi:C364AC71-36DB-495A-8494-B439D472A505");
30 
31 static struct platform_device *tc1100_device;
32 
33 struct tc1100_data {
34 	u32 wireless;
35 	u32 jogdial;
36 };
37 
38 #ifdef CONFIG_PM
39 static struct tc1100_data suspend_data;
40 #endif
41 
42 /* --------------------------------------------------------------------------
43 				Device Management
44    -------------------------------------------------------------------------- */
45 
46 static int get_state(u32 *out, u8 instance)
47 {
48 	u32 tmp;
49 	acpi_status status;
50 	struct acpi_buffer result = { ACPI_ALLOCATE_BUFFER, NULL };
51 	union acpi_object *obj;
52 
53 	if (!out)
54 		return -EINVAL;
55 
56 	if (instance > 2)
57 		return -ENODEV;
58 
59 	status = wmi_query_block(GUID, instance, &result);
60 	if (ACPI_FAILURE(status))
61 		return -ENODEV;
62 
63 	obj = (union acpi_object *) result.pointer;
64 	if (obj && obj->type == ACPI_TYPE_INTEGER) {
65 		tmp = obj->integer.value;
66 	} else {
67 		tmp = 0;
68 	}
69 
70 	if (result.length > 0)
71 		kfree(result.pointer);
72 
73 	switch (instance) {
74 	case TC1100_INSTANCE_WIRELESS:
75 		*out = (tmp == 3) ? 1 : 0;
76 		return 0;
77 	case TC1100_INSTANCE_JOGDIAL:
78 		*out = (tmp == 1) ? 0 : 1;
79 		return 0;
80 	default:
81 		return -ENODEV;
82 	}
83 }
84 
85 static int set_state(u32 *in, u8 instance)
86 {
87 	u32 value;
88 	acpi_status status;
89 	struct acpi_buffer input;
90 
91 	if (!in)
92 		return -EINVAL;
93 
94 	if (instance > 2)
95 		return -ENODEV;
96 
97 	switch (instance) {
98 	case TC1100_INSTANCE_WIRELESS:
99 		value = (*in) ? 1 : 2;
100 		break;
101 	case TC1100_INSTANCE_JOGDIAL:
102 		value = (*in) ? 0 : 1;
103 		break;
104 	default:
105 		return -ENODEV;
106 	}
107 
108 	input.length = sizeof(u32);
109 	input.pointer = &value;
110 
111 	status = wmi_set_block(GUID, instance, &input);
112 	if (ACPI_FAILURE(status))
113 		return -ENODEV;
114 
115 	return 0;
116 }
117 
118 /* --------------------------------------------------------------------------
119 				FS Interface (/sys)
120    -------------------------------------------------------------------------- */
121 
122 /*
123  * Read/ write bool sysfs macro
124  */
125 #define show_set_bool(value, instance) \
126 static ssize_t \
127 show_bool_##value(struct device *dev, struct device_attribute *attr, \
128 	char *buf) \
129 { \
130 	u32 result; \
131 	acpi_status status = get_state(&result, instance); \
132 	if (ACPI_SUCCESS(status)) \
133 		return sprintf(buf, "%d\n", result); \
134 	return sprintf(buf, "Read error\n"); \
135 } \
136 \
137 static ssize_t \
138 set_bool_##value(struct device *dev, struct device_attribute *attr, \
139 	const char *buf, size_t count) \
140 { \
141 	u32 tmp = simple_strtoul(buf, NULL, 10); \
142 	acpi_status status = set_state(&tmp, instance); \
143 		if (ACPI_FAILURE(status)) \
144 			return -EINVAL; \
145 	return count; \
146 } \
147 static DEVICE_ATTR(value, S_IRUGO | S_IWUSR, \
148 	show_bool_##value, set_bool_##value);
149 
150 show_set_bool(wireless, TC1100_INSTANCE_WIRELESS);
151 show_set_bool(jogdial, TC1100_INSTANCE_JOGDIAL);
152 
153 static struct attribute *tc1100_attributes[] = {
154 	&dev_attr_wireless.attr,
155 	&dev_attr_jogdial.attr,
156 	NULL
157 };
158 
159 static const struct attribute_group tc1100_attribute_group = {
160 	.attrs	= tc1100_attributes,
161 };
162 
163 /* --------------------------------------------------------------------------
164 				Driver Model
165    -------------------------------------------------------------------------- */
166 
167 static int __init tc1100_probe(struct platform_device *device)
168 {
169 	return sysfs_create_group(&device->dev.kobj, &tc1100_attribute_group);
170 }
171 
172 
173 static int tc1100_remove(struct platform_device *device)
174 {
175 	sysfs_remove_group(&device->dev.kobj, &tc1100_attribute_group);
176 
177 	return 0;
178 }
179 
180 #ifdef CONFIG_PM
181 static int tc1100_suspend(struct device *dev)
182 {
183 	int ret;
184 
185 	ret = get_state(&suspend_data.wireless, TC1100_INSTANCE_WIRELESS);
186 	if (ret)
187 		return ret;
188 
189 	ret = get_state(&suspend_data.jogdial, TC1100_INSTANCE_JOGDIAL);
190 	if (ret)
191 		return ret;
192 
193 	return 0;
194 }
195 
196 static int tc1100_resume(struct device *dev)
197 {
198 	int ret;
199 
200 	ret = set_state(&suspend_data.wireless, TC1100_INSTANCE_WIRELESS);
201 	if (ret)
202 		return ret;
203 
204 	ret = set_state(&suspend_data.jogdial, TC1100_INSTANCE_JOGDIAL);
205 	if (ret)
206 		return ret;
207 
208 	return 0;
209 }
210 
211 static const struct dev_pm_ops tc1100_pm_ops = {
212 	.suspend	= tc1100_suspend,
213 	.resume		= tc1100_resume,
214 	.freeze		= tc1100_suspend,
215 	.restore	= tc1100_resume,
216 };
217 #endif
218 
219 static struct platform_driver tc1100_driver = {
220 	.driver = {
221 		.name = "tc1100-wmi",
222 #ifdef CONFIG_PM
223 		.pm = &tc1100_pm_ops,
224 #endif
225 	},
226 	.remove = tc1100_remove,
227 };
228 
229 static int __init tc1100_init(void)
230 {
231 	int error;
232 
233 	if (!wmi_has_guid(GUID))
234 		return -ENODEV;
235 
236 	tc1100_device = platform_device_alloc("tc1100-wmi", PLATFORM_DEVID_NONE);
237 	if (!tc1100_device)
238 		return -ENOMEM;
239 
240 	error = platform_device_add(tc1100_device);
241 	if (error)
242 		goto err_device_put;
243 
244 	error = platform_driver_probe(&tc1100_driver, tc1100_probe);
245 	if (error)
246 		goto err_device_del;
247 
248 	pr_info("HP Compaq TC1100 Tablet WMI Extras loaded\n");
249 	return 0;
250 
251  err_device_del:
252 	platform_device_del(tc1100_device);
253  err_device_put:
254 	platform_device_put(tc1100_device);
255 	return error;
256 }
257 
258 static void __exit tc1100_exit(void)
259 {
260 	platform_device_unregister(tc1100_device);
261 	platform_driver_unregister(&tc1100_driver);
262 }
263 
264 module_init(tc1100_init);
265 module_exit(tc1100_exit);
266