]> git.karo-electronics.de Git - karo-tx-linux.git/blob - drivers/platform/x86/surfacepro3_button.c
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
[karo-tx-linux.git] / drivers / platform / x86 / surfacepro3_button.c
1 /*
2  * power/home/volume button support for
3  * Microsoft Surface Pro 3/4 tablet.
4  *
5  * Copyright (c) 2015 Intel Corporation.
6  * All rights reserved.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * as published by the Free Software Foundation; version 2
11  * of the License.
12  */
13
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/types.h>
18 #include <linux/input.h>
19 #include <linux/acpi.h>
20 #include <acpi/button.h>
21
22 #define SURFACE_PRO3_BUTTON_HID         "MSHW0028"
23 #define SURFACE_PRO4_BUTTON_HID         "MSHW0040"
24 #define SURFACE_BUTTON_OBJ_NAME         "VGBI"
25 #define SURFACE_BUTTON_DEVICE_NAME      "Surface Pro 3/4 Buttons"
26
27 #define SURFACE_BUTTON_NOTIFY_TABLET_MODE       0xc8
28
29 #define SURFACE_BUTTON_NOTIFY_PRESS_POWER       0xc6
30 #define SURFACE_BUTTON_NOTIFY_RELEASE_POWER     0xc7
31
32 #define SURFACE_BUTTON_NOTIFY_PRESS_HOME        0xc4
33 #define SURFACE_BUTTON_NOTIFY_RELEASE_HOME      0xc5
34
35 #define SURFACE_BUTTON_NOTIFY_PRESS_VOLUME_UP   0xc0
36 #define SURFACE_BUTTON_NOTIFY_RELEASE_VOLUME_UP 0xc1
37
38 #define SURFACE_BUTTON_NOTIFY_PRESS_VOLUME_DOWN         0xc2
39 #define SURFACE_BUTTON_NOTIFY_RELEASE_VOLUME_DOWN       0xc3
40
41 ACPI_MODULE_NAME("surface pro 3 button");
42
43 MODULE_AUTHOR("Chen Yu");
44 MODULE_DESCRIPTION("Surface Pro3 Button Driver");
45 MODULE_LICENSE("GPL v2");
46
47 /*
48  * Power button, Home button, Volume buttons support is supposed to
49  * be covered by drivers/input/misc/soc_button_array.c, which is implemented
50  * according to "Windows ACPI Design Guide for SoC Platforms".
51  * However surface pro3 seems not to obey the specs, instead it uses
52  * device VGBI(MSHW0028) for dispatching the events.
53  * We choose acpi_driver rather than platform_driver/i2c_driver because
54  * although VGBI has an i2c resource connected to i2c controller, it
55  * is not embedded in any i2c controller's scope, thus neither platform_device
56  * will be created, nor i2c_client will be enumerated, we have to use
57  * acpi_driver.
58  */
59 static const struct acpi_device_id surface_button_device_ids[] = {
60         {SURFACE_PRO3_BUTTON_HID,    0},
61         {SURFACE_PRO4_BUTTON_HID,    0},
62         {"", 0},
63 };
64 MODULE_DEVICE_TABLE(acpi, surface_button_device_ids);
65
66 struct surface_button {
67         unsigned int type;
68         struct input_dev *input;
69         char phys[32];                  /* for input device */
70         unsigned long pushed;
71         bool suspended;
72 };
73
74 static void surface_button_notify(struct acpi_device *device, u32 event)
75 {
76         struct surface_button *button = acpi_driver_data(device);
77         struct input_dev *input;
78         int key_code = KEY_RESERVED;
79         bool pressed = false;
80
81         switch (event) {
82         /* Power button press,release handle */
83         case SURFACE_BUTTON_NOTIFY_PRESS_POWER:
84                 pressed = true;
85                 /*fall through*/
86         case SURFACE_BUTTON_NOTIFY_RELEASE_POWER:
87                 key_code = KEY_POWER;
88                 break;
89         /* Home button press,release handle */
90         case SURFACE_BUTTON_NOTIFY_PRESS_HOME:
91                 pressed = true;
92                 /*fall through*/
93         case SURFACE_BUTTON_NOTIFY_RELEASE_HOME:
94                 key_code = KEY_LEFTMETA;
95                 break;
96         /* Volume up button press,release handle */
97         case SURFACE_BUTTON_NOTIFY_PRESS_VOLUME_UP:
98                 pressed = true;
99                 /*fall through*/
100         case SURFACE_BUTTON_NOTIFY_RELEASE_VOLUME_UP:
101                 key_code = KEY_VOLUMEUP;
102                 break;
103         /* Volume down button press,release handle */
104         case SURFACE_BUTTON_NOTIFY_PRESS_VOLUME_DOWN:
105                 pressed = true;
106                 /*fall through*/
107         case SURFACE_BUTTON_NOTIFY_RELEASE_VOLUME_DOWN:
108                 key_code = KEY_VOLUMEDOWN;
109                 break;
110         case SURFACE_BUTTON_NOTIFY_TABLET_MODE:
111                 dev_warn_once(&device->dev, "Tablet mode is not supported\n");
112                 break;
113         default:
114                 dev_info_ratelimited(&device->dev,
115                                      "Unsupported event [0x%x]\n", event);
116                 break;
117         }
118         input = button->input;
119         if (key_code == KEY_RESERVED)
120                 return;
121         if (pressed)
122                 pm_wakeup_event(&device->dev, 0);
123         if (button->suspended)
124                 return;
125         input_report_key(input, key_code, pressed?1:0);
126         input_sync(input);
127 }
128
129 #ifdef CONFIG_PM_SLEEP
130 static int surface_button_suspend(struct device *dev)
131 {
132         struct acpi_device *device = to_acpi_device(dev);
133         struct surface_button *button = acpi_driver_data(device);
134
135         button->suspended = true;
136         return 0;
137 }
138
139 static int surface_button_resume(struct device *dev)
140 {
141         struct acpi_device *device = to_acpi_device(dev);
142         struct surface_button *button = acpi_driver_data(device);
143
144         button->suspended = false;
145         return 0;
146 }
147 #endif
148
149 static int surface_button_add(struct acpi_device *device)
150 {
151         struct surface_button *button;
152         struct input_dev *input;
153         const char *hid = acpi_device_hid(device);
154         char *name;
155         int error;
156
157         if (strncmp(acpi_device_bid(device), SURFACE_BUTTON_OBJ_NAME,
158             strlen(SURFACE_BUTTON_OBJ_NAME)))
159                 return -ENODEV;
160
161         button = kzalloc(sizeof(struct surface_button), GFP_KERNEL);
162         if (!button)
163                 return -ENOMEM;
164
165         device->driver_data = button;
166         button->input = input = input_allocate_device();
167         if (!input) {
168                 error = -ENOMEM;
169                 goto err_free_button;
170         }
171
172         name = acpi_device_name(device);
173         strcpy(name, SURFACE_BUTTON_DEVICE_NAME);
174         snprintf(button->phys, sizeof(button->phys), "%s/buttons", hid);
175
176         input->name = name;
177         input->phys = button->phys;
178         input->id.bustype = BUS_HOST;
179         input->dev.parent = &device->dev;
180         input_set_capability(input, EV_KEY, KEY_POWER);
181         input_set_capability(input, EV_KEY, KEY_LEFTMETA);
182         input_set_capability(input, EV_KEY, KEY_VOLUMEUP);
183         input_set_capability(input, EV_KEY, KEY_VOLUMEDOWN);
184
185         error = input_register_device(input);
186         if (error)
187                 goto err_free_input;
188         dev_info(&device->dev,
189                         "%s [%s]\n", name, acpi_device_bid(device));
190         return 0;
191
192  err_free_input:
193         input_free_device(input);
194  err_free_button:
195         kfree(button);
196         return error;
197 }
198
199 static int surface_button_remove(struct acpi_device *device)
200 {
201         struct surface_button *button = acpi_driver_data(device);
202
203         input_unregister_device(button->input);
204         kfree(button);
205         return 0;
206 }
207
208 static SIMPLE_DEV_PM_OPS(surface_button_pm,
209                 surface_button_suspend, surface_button_resume);
210
211 static struct acpi_driver surface_button_driver = {
212         .name = "surface_pro3_button",
213         .class = "SurfacePro3",
214         .ids = surface_button_device_ids,
215         .ops = {
216                 .add = surface_button_add,
217                 .remove = surface_button_remove,
218                 .notify = surface_button_notify,
219         },
220         .drv.pm = &surface_button_pm,
221 };
222
223 module_acpi_driver(surface_button_driver);