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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * OLPC XO-1.5 ebook switch driver4 * (based on generic ACPI button driver)5 *6 * Copyright (C) 2009 Paul Fox <pgf@laptop.org>7 * Copyright (C) 2010 One Laptop per Child8 */9 10#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt11 12#include <linux/kernel.h>13#include <linux/module.h>14#include <linux/init.h>15#include <linux/types.h>16#include <linux/input.h>17#include <linux/acpi.h>18 19#define MODULE_NAME "xo15-ebook"20 21#define XO15_EBOOK_CLASS MODULE_NAME22#define XO15_EBOOK_TYPE_UNKNOWN 0x0023#define XO15_EBOOK_NOTIFY_STATUS 0x8024 25#define XO15_EBOOK_SUBCLASS "ebook"26#define XO15_EBOOK_HID "XO15EBK"27#define XO15_EBOOK_DEVICE_NAME "EBook Switch"28 29MODULE_DESCRIPTION("OLPC XO-1.5 ebook switch driver");30MODULE_LICENSE("GPL");31 32static const struct acpi_device_id ebook_device_ids[] = {33 { XO15_EBOOK_HID, 0 },34 { "", 0 },35};36MODULE_DEVICE_TABLE(acpi, ebook_device_ids);37 38struct ebook_switch {39 struct input_dev *input;40 char phys[32]; /* for input device */41};42 43static int ebook_send_state(struct acpi_device *device)44{45 struct ebook_switch *button = acpi_driver_data(device);46 unsigned long long state;47 acpi_status status;48 49 status = acpi_evaluate_integer(device->handle, "EBK", NULL, &state);50 if (ACPI_FAILURE(status))51 return -EIO;52 53 /* input layer checks if event is redundant */54 input_report_switch(button->input, SW_TABLET_MODE, !state);55 input_sync(button->input);56 return 0;57}58 59static void ebook_switch_notify(struct acpi_device *device, u32 event)60{61 switch (event) {62 case ACPI_FIXED_HARDWARE_EVENT:63 case XO15_EBOOK_NOTIFY_STATUS:64 ebook_send_state(device);65 break;66 default:67 acpi_handle_debug(device->handle,68 "Unsupported event [0x%x]\n", event);69 break;70 }71}72 73#ifdef CONFIG_PM_SLEEP74static int ebook_switch_resume(struct device *dev)75{76 return ebook_send_state(to_acpi_device(dev));77}78#endif79 80static SIMPLE_DEV_PM_OPS(ebook_switch_pm, NULL, ebook_switch_resume);81 82static int ebook_switch_add(struct acpi_device *device)83{84 const struct acpi_device_id *id;85 struct ebook_switch *button;86 struct input_dev *input;87 char *name, *class;88 int error;89 90 button = kzalloc(sizeof(struct ebook_switch), GFP_KERNEL);91 if (!button)92 return -ENOMEM;93 94 device->driver_data = button;95 96 button->input = input = input_allocate_device();97 if (!input) {98 error = -ENOMEM;99 goto err_free_button;100 }101 102 name = acpi_device_name(device);103 class = acpi_device_class(device);104 105 id = acpi_match_acpi_device(ebook_device_ids, device);106 if (!id) {107 dev_err(&device->dev, "Unsupported hid\n");108 error = -ENODEV;109 goto err_free_input;110 }111 112 strcpy(name, XO15_EBOOK_DEVICE_NAME);113 sprintf(class, "%s/%s", XO15_EBOOK_CLASS, XO15_EBOOK_SUBCLASS);114 115 snprintf(button->phys, sizeof(button->phys), "%s/button/input0", id->id);116 117 input->name = name;118 input->phys = button->phys;119 input->id.bustype = BUS_HOST;120 input->dev.parent = &device->dev;121 122 input->evbit[0] = BIT_MASK(EV_SW);123 set_bit(SW_TABLET_MODE, input->swbit);124 125 error = input_register_device(input);126 if (error)127 goto err_free_input;128 129 ebook_send_state(device);130 131 if (device->wakeup.flags.valid) {132 /* Button's GPE is run-wake GPE */133 acpi_enable_gpe(device->wakeup.gpe_device,134 device->wakeup.gpe_number);135 device_set_wakeup_enable(&device->dev, true);136 }137 138 return 0;139 140 err_free_input:141 input_free_device(input);142 err_free_button:143 kfree(button);144 return error;145}146 147static void ebook_switch_remove(struct acpi_device *device)148{149 struct ebook_switch *button = acpi_driver_data(device);150 151 input_unregister_device(button->input);152 kfree(button);153}154 155static struct acpi_driver xo15_ebook_driver = {156 .name = MODULE_NAME,157 .class = XO15_EBOOK_CLASS,158 .ids = ebook_device_ids,159 .ops = {160 .add = ebook_switch_add,161 .remove = ebook_switch_remove,162 .notify = ebook_switch_notify,163 },164 .drv.pm = &ebook_switch_pm,165};166module_acpi_driver(xo15_ebook_driver);167