/* * power/home/volume button support for * Microsoft Surface Pro 3/4 tablet. * * Copyright (c) 2015 Intel Corporation. * All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; version 2 * of the License. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/types.h> #include <linux/input.h> #include <linux/acpi.h> #include <acpi/button.h> #define SURFACE_PRO3_BUTTON_HID "MSHW0028" #define SURFACE_PRO4_BUTTON_HID "MSHW0040" #define SURFACE_BUTTON_OBJ_NAME "VGBI" #define SURFACE_BUTTON_DEVICE_NAME "Surface Pro 3/4 Buttons" #define SURFACE_BUTTON_NOTIFY_TABLET_MODE 0xc8 #define SURFACE_BUTTON_NOTIFY_PRESS_POWER 0xc6 #define SURFACE_BUTTON_NOTIFY_RELEASE_POWER 0xc7 #define SURFACE_BUTTON_NOTIFY_PRESS_HOME 0xc4 #define SURFACE_BUTTON_NOTIFY_RELEASE_HOME 0xc5 #define SURFACE_BUTTON_NOTIFY_PRESS_VOLUME_UP 0xc0 #define SURFACE_BUTTON_NOTIFY_RELEASE_VOLUME_UP 0xc1 #define SURFACE_BUTTON_NOTIFY_PRESS_VOLUME_DOWN 0xc2 #define SURFACE_BUTTON_NOTIFY_RELEASE_VOLUME_DOWN 0xc3 ACPI_MODULE_NAME("surface pro 3 button"); MODULE_AUTHOR("Chen Yu"); MODULE_DESCRIPTION("Surface Pro3 Button Driver"); MODULE_LICENSE("GPL v2"); /* * Power button, Home button, Volume buttons support is supposed to * be covered by drivers/input/misc/soc_button_array.c, which is implemented * according to "Windows ACPI Design Guide for SoC Platforms". * However surface pro3 seems not to obey the specs, instead it uses * device VGBI(MSHW0028) for dispatching the events. * We choose acpi_driver rather than platform_driver/i2c_driver because * although VGBI has an i2c resource connected to i2c controller, it * is not embedded in any i2c controller's scope, thus neither platform_device * will be created, nor i2c_client will be enumerated, we have to use * acpi_driver. */ static const struct acpi_device_id surface_button_device_ids[] = { {SURFACE_PRO3_BUTTON_HID, 0}, {SURFACE_PRO4_BUTTON_HID, 0}, {"", 0}, }; MODULE_DEVICE_TABLE(acpi, surface_button_device_ids); struct surface_button { unsigned int type; struct input_dev *input; char phys[32]; /* for input device */ unsigned long pushed; bool suspended; }; static void surface_button_notify(struct acpi_device *device, u32 event) { struct surface_button *button = acpi_driver_data(device); struct input_dev *input; int key_code = KEY_RESERVED; bool pressed = false; switch (event) { /* Power button press,release handle */ case SURFACE_BUTTON_NOTIFY_PRESS_POWER: pressed = true; /*fall through*/ case SURFACE_BUTTON_NOTIFY_RELEASE_POWER: key_code = KEY_POWER; break; /* Home button press,release handle */ case SURFACE_BUTTON_NOTIFY_PRESS_HOME: pressed = true; /*fall through*/ case SURFACE_BUTTON_NOTIFY_RELEASE_HOME: key_code = KEY_LEFTMETA; break; /* Volume up button press,release handle */ case SURFACE_BUTTON_NOTIFY_PRESS_VOLUME_UP: pressed = true; /*fall through*/ case SURFACE_BUTTON_NOTIFY_RELEASE_VOLUME_UP: key_code = KEY_VOLUMEUP; break; /* Volume down button press,release handle */ case SURFACE_BUTTON_NOTIFY_PRESS_VOLUME_DOWN: pressed = true; /*fall through*/ case SURFACE_BUTTON_NOTIFY_RELEASE_VOLUME_DOWN: key_code = KEY_VOLUMEDOWN; break; case SURFACE_BUTTON_NOTIFY_TABLET_MODE: dev_warn_once(&device->dev, "Tablet mode is not supported\n"); break; default: dev_info_ratelimited(&device->dev, "Unsupported event [0x%x]\n", event); break; } input = button->input; if (key_code == KEY_RESERVED) return; if (pressed) pm_wakeup_event(&device->dev, 0); if (button->suspended) return; input_report_key(input, key_code, pressed?1:0); input_sync(input); } #ifdef CONFIG_PM_SLEEP static int surface_button_suspend(struct device *dev) { struct acpi_device *device = to_acpi_device(dev); struct surface_button *button = acpi_driver_data(device); button->suspended = true; return 0; } static int surface_button_resume(struct device *dev) { struct acpi_device *device = to_acpi_device(dev); struct surface_button *button = acpi_driver_data(device); button->suspended = false; return 0; } #endif static int surface_button_add(struct acpi_device *device) { struct surface_button *button; struct input_dev *input; const char *hid = acpi_device_hid(device); char *name; int error; if (strncmp(acpi_device_bid(device), SURFACE_BUTTON_OBJ_NAME, strlen(SURFACE_BUTTON_OBJ_NAME))) return -ENODEV; button = kzalloc(sizeof(struct surface_button), GFP_KERNEL); if (!button) return -ENOMEM; device->driver_data = button; button->input = input = input_allocate_device(); if (!input) { error = -ENOMEM; goto err_free_button; } name = acpi_device_name(device); strcpy(name, SURFACE_BUTTON_DEVICE_NAME); snprintf(button->phys, sizeof(button->phys), "%s/buttons", hid); input->name = name; input->phys = button->phys; input->id.bustype = BUS_HOST; input->dev.parent = &device->dev; input_set_capability(input, EV_KEY, KEY_POWER); input_set_capability(input, EV_KEY, KEY_LEFTMETA); input_set_capability(input, EV_KEY, KEY_VOLUMEUP); input_set_capability(input, EV_KEY, KEY_VOLUMEDOWN); error = input_register_device(input); if (error) goto err_free_input; dev_info(&device->dev, "%s [%s]\n", name, acpi_device_bid(device)); return 0; err_free_input: input_free_device(input); err_free_button: kfree(button); return error; } static int surface_button_remove(struct acpi_device *device) { struct surface_button *button = acpi_driver_data(device); input_unregister_device(button->input); kfree(button); return 0; } static SIMPLE_DEV_PM_OPS(surface_button_pm, surface_button_suspend, surface_button_resume); static struct acpi_driver surface_button_driver = { .name = "surface_pro3_button", .class = "SurfacePro3", .ids = surface_button_device_ids, .ops = { .add = surface_button_add, .remove = surface_button_remove, .notify = surface_button_notify, }, .drv.pm = &surface_button_pm, }; module_acpi_driver(surface_button_driver);