1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Author: Sudeep Holla <sudeep.holla@arm.com>
4 * Copyright 2022 Arm Limited
5 */
6#include <linux/kernel.h>
7#include <linux/acpi.h>
8#include <linux/completion.h>
9#include <linux/idr.h>
10#include <linux/io.h>
11
12static struct acpi_ffh_info ffh_ctx;
13
14int __weak acpi_ffh_address_space_arch_setup(void *handler_ctxt,
15 void **region_ctxt)
16{
17 return -EOPNOTSUPP;
18}
19
20int __weak acpi_ffh_address_space_arch_handler(acpi_integer *value,
21 void *region_context)
22{
23 return -EOPNOTSUPP;
24}
25
26static acpi_status
27acpi_ffh_address_space_setup(acpi_handle region_handle, u32 function,
28 void *handler_context, void **region_context)
29{
30 return acpi_ffh_address_space_arch_setup(handler_ctxt: handler_context,
31 region_ctxt: region_context);
32}
33
34static acpi_status
35acpi_ffh_address_space_handler(u32 function, acpi_physical_address addr,
36 u32 bits, acpi_integer *value,
37 void *handler_context, void *region_context)
38{
39 return acpi_ffh_address_space_arch_handler(value, region_context);
40}
41
42void __init acpi_init_ffh(void)
43{
44 acpi_status status;
45
46 status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
47 ACPI_ADR_SPACE_FIXED_HARDWARE,
48 handler: &acpi_ffh_address_space_handler,
49 setup: &acpi_ffh_address_space_setup,
50 context: &ffh_ctx);
51 if (ACPI_FAILURE(status))
52 pr_alert("OperationRegion handler could not be installed\n");
53}
54

source code of linux/drivers/acpi/acpi_ffh.c