swh:1:snp:c3bf2749e3476071fa748f67b0ffa2fdc5fe49d9
Tip revision: 4b0986a3613c92f4ec1bdc7f60ec66fea135991f authored by Linus Torvalds on 22 May 2022, 19:52:31 UTC
Linux 5.18
Linux 5.18
Tip revision: 4b0986a
i2c-hid-acpi.c
/*
* HID over I2C ACPI Subclass
*
* Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
* Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
* Copyright (c) 2012 Red Hat, Inc
*
* This code was forked out of the core code, which was partly based on
* "USB HID support for Linux":
*
* Copyright (c) 1999 Andreas Gal
* Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
* Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
* Copyright (c) 2007-2008 Oliver Neukum
* Copyright (c) 2006-2010 Jiri Kosina
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive for
* more details.
*/
#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pm.h>
#include <linux/uuid.h>
#include "i2c-hid.h"
struct i2c_hid_acpi {
struct i2chid_ops ops;
struct acpi_device *adev;
};
static const struct acpi_device_id i2c_hid_acpi_blacklist[] = {
/*
* The CHPN0001 ACPI device, which is used to describe the Chipone
* ICN8505 controller, has a _CID of PNP0C50 but is not HID compatible.
*/
{"CHPN0001", 0 },
{ },
};
/* HID I²C Device: 3cdff6f7-4267-4555-ad05-b30a3d8938de */
static guid_t i2c_hid_guid =
GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
static int i2c_hid_acpi_get_descriptor(struct acpi_device *adev)
{
acpi_handle handle = acpi_device_handle(adev);
union acpi_object *obj;
u16 hid_descriptor_address;
if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0)
return -ENODEV;
obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL,
ACPI_TYPE_INTEGER);
if (!obj) {
acpi_handle_err(handle, "Error _DSM call to get HID descriptor address failed\n");
return -ENODEV;
}
hid_descriptor_address = obj->integer.value;
ACPI_FREE(obj);
return hid_descriptor_address;
}
static void i2c_hid_acpi_shutdown_tail(struct i2chid_ops *ops)
{
struct i2c_hid_acpi *ihid_acpi = container_of(ops, struct i2c_hid_acpi, ops);
acpi_device_set_power(ihid_acpi->adev, ACPI_STATE_D3_COLD);
}
static int i2c_hid_acpi_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct i2c_hid_acpi *ihid_acpi;
struct acpi_device *adev;
u16 hid_descriptor_address;
int ret;
adev = ACPI_COMPANION(dev);
if (!adev) {
dev_err(&client->dev, "Error could not get ACPI device\n");
return -ENODEV;
}
ihid_acpi = devm_kzalloc(&client->dev, sizeof(*ihid_acpi), GFP_KERNEL);
if (!ihid_acpi)
return -ENOMEM;
ihid_acpi->adev = adev;
ihid_acpi->ops.shutdown_tail = i2c_hid_acpi_shutdown_tail;
ret = i2c_hid_acpi_get_descriptor(adev);
if (ret < 0)
return ret;
hid_descriptor_address = ret;
acpi_device_fix_up_power(adev);
if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) {
device_set_wakeup_capable(dev, true);
device_set_wakeup_enable(dev, false);
}
return i2c_hid_core_probe(client, &ihid_acpi->ops,
hid_descriptor_address, 0);
}
static const struct acpi_device_id i2c_hid_acpi_match[] = {
{"ACPI0C50", 0 },
{"PNP0C50", 0 },
{ },
};
MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match);
static struct i2c_driver i2c_hid_acpi_driver = {
.driver = {
.name = "i2c_hid_acpi",
.pm = &i2c_hid_core_pm,
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
.acpi_match_table = i2c_hid_acpi_match,
},
.probe_new = i2c_hid_acpi_probe,
.remove = i2c_hid_core_remove,
.shutdown = i2c_hid_core_shutdown,
};
module_i2c_driver(i2c_hid_acpi_driver);
MODULE_DESCRIPTION("HID over I2C ACPI driver");
MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
MODULE_LICENSE("GPL");