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9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/slab.h>
12
13#include <linux/acpi.h>
14#include <linux/dmi.h>
15#include <linux/input.h>
16#include <linux/mutex.h>
17#include <linux/platform_device.h>
18#include <linux/spi/spi.h>
19
20MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@redhat.com>");
21MODULE_DESCRIPTION("Surface 3 platform driver");
22MODULE_LICENSE("GPL");
23
24#define ACPI_BUTTON_HID_LID "PNP0C0D"
25#define SPI_CTL_OBJ_NAME "SPI"
26#define SPI_TS_OBJ_NAME "NTRG"
27
28#define SURFACE3_LID_GUID "F7CC25EC-D20B-404C-8903-0ED4359C18AE"
29
30MODULE_ALIAS("wmi:" SURFACE3_LID_GUID);
31
32static const struct dmi_system_id surface3_dmi_table[] = {
33#if defined(CONFIG_X86)
34 {
35 .matches = {
36 DMI_MATCH(DMI_SYS_VENDOR, "Microsoft Corporation"),
37 DMI_MATCH(DMI_PRODUCT_NAME, "Surface 3"),
38 },
39 },
40#endif
41 { }
42};
43
44struct surface3_wmi {
45 struct acpi_device *touchscreen_adev;
46 struct acpi_device *pnp0c0d_adev;
47 struct acpi_hotplug_context hp;
48 struct input_dev *input;
49};
50
51static struct platform_device *s3_wmi_pdev;
52
53static struct surface3_wmi s3_wmi;
54
55static DEFINE_MUTEX(s3_wmi_lock);
56
57static int s3_wmi_query_block(const char *guid, int instance, int *ret)
58{
59 struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
60 acpi_status status;
61 union acpi_object *obj;
62 int error = 0;
63
64 mutex_lock(&s3_wmi_lock);
65 status = wmi_query_block(guid, instance, &output);
66
67 obj = output.pointer;
68
69 if (!obj || obj->type != ACPI_TYPE_INTEGER) {
70 if (obj) {
71 pr_err("query block returned object type: %d - buffer length:%d\n",
72 obj->type,
73 obj->type == ACPI_TYPE_BUFFER ?
74 obj->buffer.length : 0);
75 }
76 error = -EINVAL;
77 goto out_free_unlock;
78 }
79 *ret = obj->integer.value;
80 out_free_unlock:
81 kfree(obj);
82 mutex_unlock(&s3_wmi_lock);
83 return error;
84}
85
86static inline int s3_wmi_query_lid(int *ret)
87{
88 return s3_wmi_query_block(SURFACE3_LID_GUID, 0, ret);
89}
90
91static int s3_wmi_send_lid_state(void)
92{
93 int ret, lid_sw;
94
95 ret = s3_wmi_query_lid(&lid_sw);
96 if (ret)
97 return ret;
98
99 input_report_switch(s3_wmi.input, SW_LID, lid_sw);
100 input_sync(s3_wmi.input);
101
102 return 0;
103}
104
105static int s3_wmi_hp_notify(struct acpi_device *adev, u32 value)
106{
107 return s3_wmi_send_lid_state();
108}
109
110static acpi_status s3_wmi_attach_spi_device(acpi_handle handle,
111 u32 level,
112 void *data,
113 void **return_value)
114{
115 struct acpi_device *adev, **ts_adev;
116
117 if (acpi_bus_get_device(handle, &adev))
118 return AE_OK;
119
120 ts_adev = data;
121
122 if (strncmp(acpi_device_bid(adev), SPI_TS_OBJ_NAME,
123 strlen(SPI_TS_OBJ_NAME)))
124 return AE_OK;
125
126 if (*ts_adev) {
127 pr_err("duplicate entry %s\n", SPI_TS_OBJ_NAME);
128 return AE_OK;
129 }
130
131 *ts_adev = adev;
132
133 return AE_OK;
134}
135
136static int s3_wmi_check_platform_device(struct device *dev, void *data)
137{
138 struct acpi_device *adev, *ts_adev = NULL;
139 acpi_handle handle;
140 acpi_status status;
141
142
143 handle = ACPI_HANDLE(dev);
144 if (!handle || acpi_bus_get_device(handle, &adev))
145 return 0;
146
147
148 if (!strcmp(ACPI_BUTTON_HID_LID, acpi_device_hid(adev))) {
149 s3_wmi.pnp0c0d_adev = adev;
150 return 0;
151 }
152
153
154 if (strncmp(acpi_device_bid(adev), SPI_CTL_OBJ_NAME,
155 strlen(SPI_CTL_OBJ_NAME)))
156 return 0;
157
158 status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
159 s3_wmi_attach_spi_device, NULL,
160 &ts_adev, NULL);
161 if (ACPI_FAILURE(status))
162 dev_warn(dev, "failed to enumerate SPI slaves\n");
163
164 if (!ts_adev)
165 return 0;
166
167 s3_wmi.touchscreen_adev = ts_adev;
168
169 return 0;
170}
171
172static int s3_wmi_create_and_register_input(struct platform_device *pdev)
173{
174 struct input_dev *input;
175 int error;
176
177 input = devm_input_allocate_device(&pdev->dev);
178 if (!input)
179 return -ENOMEM;
180
181 input->name = "Lid Switch";
182 input->phys = "button/input0";
183 input->id.bustype = BUS_HOST;
184 input->id.product = 0x0005;
185
186 input_set_capability(input, EV_SW, SW_LID);
187
188 error = input_register_device(input);
189 if (error)
190 goto out_err;
191
192 s3_wmi.input = input;
193
194 return 0;
195 out_err:
196 input_free_device(s3_wmi.input);
197 return error;
198}
199
200static int __init s3_wmi_probe(struct platform_device *pdev)
201{
202 int error;
203
204 if (!dmi_check_system(surface3_dmi_table))
205 return -ENODEV;
206
207 memset(&s3_wmi, 0, sizeof(s3_wmi));
208
209 bus_for_each_dev(&platform_bus_type, NULL, NULL,
210 s3_wmi_check_platform_device);
211
212 if (!s3_wmi.touchscreen_adev)
213 return -ENODEV;
214
215 acpi_bus_trim(s3_wmi.pnp0c0d_adev);
216
217 error = s3_wmi_create_and_register_input(pdev);
218 if (error)
219 goto restore_acpi_lid;
220
221 acpi_initialize_hp_context(s3_wmi.touchscreen_adev, &s3_wmi.hp,
222 s3_wmi_hp_notify, NULL);
223
224 s3_wmi_send_lid_state();
225
226 return 0;
227
228 restore_acpi_lid:
229 acpi_bus_scan(s3_wmi.pnp0c0d_adev->handle);
230 return error;
231}
232
233static int s3_wmi_remove(struct platform_device *device)
234{
235
236 s3_wmi.touchscreen_adev->hp = NULL;
237
238
239 acpi_bus_scan(s3_wmi.pnp0c0d_adev->handle);
240 return 0;
241}
242
243static int __maybe_unused s3_wmi_resume(struct device *dev)
244{
245 s3_wmi_send_lid_state();
246 return 0;
247}
248static SIMPLE_DEV_PM_OPS(s3_wmi_pm, NULL, s3_wmi_resume);
249
250static struct platform_driver s3_wmi_driver = {
251 .driver = {
252 .name = "surface3-wmi",
253 .pm = &s3_wmi_pm,
254 },
255 .remove = s3_wmi_remove,
256};
257
258static int __init s3_wmi_init(void)
259{
260 int error;
261
262 s3_wmi_pdev = platform_device_alloc("surface3-wmi", -1);
263 if (!s3_wmi_pdev)
264 return -ENOMEM;
265
266 error = platform_device_add(s3_wmi_pdev);
267 if (error)
268 goto err_device_put;
269
270 error = platform_driver_probe(&s3_wmi_driver, s3_wmi_probe);
271 if (error)
272 goto err_device_del;
273
274 pr_info("Surface 3 WMI Extras loaded\n");
275 return 0;
276
277 err_device_del:
278 platform_device_del(s3_wmi_pdev);
279 err_device_put:
280 platform_device_put(s3_wmi_pdev);
281 return error;
282}
283
284static void __exit s3_wmi_exit(void)
285{
286 platform_device_unregister(s3_wmi_pdev);
287 platform_driver_unregister(&s3_wmi_driver);
288}
289
290module_init(s3_wmi_init);
291module_exit(s3_wmi_exit);
292
