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1/*2 * HID over I2C ACPI Subclass3 *4 * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>5 * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France6 * Copyright (c) 2012 Red Hat, Inc7 *8 * This code was forked out of the core code, which was partly based on9 * "USB HID support for Linux":10 *11 *  Copyright (c) 1999 Andreas Gal12 *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>13 *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc14 *  Copyright (c) 2007-2008 Oliver Neukum15 *  Copyright (c) 2006-2010 Jiri Kosina16 *17 * This file is subject to the terms and conditions of the GNU General Public18 * License.  See the file COPYING in the main directory of this archive for19 * more details.20 */21 22#include <linux/acpi.h>23#include <linux/device.h>24#include <linux/i2c.h>25#include <linux/kernel.h>26#include <linux/module.h>27#include <linux/pm.h>28#include <linux/uuid.h>29 30#include "i2c-hid.h"31 32struct i2c_hid_acpi {33	struct i2chid_ops ops;34	struct acpi_device *adev;35};36 37static const struct acpi_device_id i2c_hid_acpi_blacklist[] = {38	/*39	 * The CHPN0001 ACPI device, which is used to describe the Chipone40	 * ICN8505 controller, has a _CID of PNP0C50 but is not HID compatible.41	 */42	{ "CHPN0001" },43	/*44	 * The IDEA5002 ACPI device causes high interrupt usage and spurious45	 * wakeups from suspend.46	 */47	{ "IDEA5002" },48	{ }49};50 51/* HID I²C Device: 3cdff6f7-4267-4555-ad05-b30a3d8938de */52static guid_t i2c_hid_guid =53	GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,54		  0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);55 56static int i2c_hid_acpi_get_descriptor(struct i2c_hid_acpi *ihid_acpi)57{58	struct acpi_device *adev = ihid_acpi->adev;59	acpi_handle handle = acpi_device_handle(adev);60	union acpi_object *obj;61	u16 hid_descriptor_address;62 63	if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0)64		return -ENODEV;65 66	obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL,67				      ACPI_TYPE_INTEGER);68	if (!obj) {69		acpi_handle_err(handle, "Error _DSM call to get HID descriptor address failed\n");70		return -ENODEV;71	}72 73	hid_descriptor_address = obj->integer.value;74	ACPI_FREE(obj);75 76	return hid_descriptor_address;77}78 79static void i2c_hid_acpi_shutdown_tail(struct i2chid_ops *ops)80{81	struct i2c_hid_acpi *ihid_acpi = container_of(ops, struct i2c_hid_acpi, ops);82 83	acpi_device_set_power(ihid_acpi->adev, ACPI_STATE_D3_COLD);84}85 86static int i2c_hid_acpi_probe(struct i2c_client *client)87{88	struct device *dev = &client->dev;89	struct i2c_hid_acpi *ihid_acpi;90	u16 hid_descriptor_address;91	int ret;92 93	ihid_acpi = devm_kzalloc(&client->dev, sizeof(*ihid_acpi), GFP_KERNEL);94	if (!ihid_acpi)95		return -ENOMEM;96 97	ihid_acpi->adev = ACPI_COMPANION(dev);98	ihid_acpi->ops.shutdown_tail = i2c_hid_acpi_shutdown_tail;99 100	ret = i2c_hid_acpi_get_descriptor(ihid_acpi);101	if (ret < 0)102		return ret;103	hid_descriptor_address = ret;104 105	acpi_device_fix_up_power(ihid_acpi->adev);106 107	return i2c_hid_core_probe(client, &ihid_acpi->ops,108				  hid_descriptor_address, 0);109}110 111static const struct acpi_device_id i2c_hid_acpi_match[] = {112	{ "ACPI0C50" },113	{ "PNP0C50" },114	{ }115};116MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match);117 118static struct i2c_driver i2c_hid_acpi_driver = {119	.driver = {120		.name	= "i2c_hid_acpi",121		.pm	= &i2c_hid_core_pm,122		.probe_type = PROBE_PREFER_ASYNCHRONOUS,123		.acpi_match_table = i2c_hid_acpi_match,124	},125 126	.probe		= i2c_hid_acpi_probe,127	.remove		= i2c_hid_core_remove,128	.shutdown	= i2c_hid_core_shutdown,129};130 131module_i2c_driver(i2c_hid_acpi_driver);132 133MODULE_DESCRIPTION("HID over I2C ACPI driver");134MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");135MODULE_LICENSE("GPL");136