drivers/acpi/acpi_ffh.c

   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
  12 static struct acpi_ffh_info ffh_ctx;
  13
  14 int __weak acpi_ffh_address_space_arch_setup(void *handler_ctxt,
  15                                              void **region_ctxt)
  16 {
  17         return -EOPNOTSUPP;
  18 }
  19
  20 int __weak acpi_ffh_address_space_arch_handler(acpi_integer *value,
  21                                                void *region_context)
  22 {
  23         return -EOPNOTSUPP;
  24 }
  25
  26 static acpi_status
  27 acpi_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_context,
  31                                                  region_context);
  32 }
  33
  34 static acpi_status
  35 acpi_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
  42 void __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                                                     &acpi_ffh_address_space_handler,
  49                                                     &acpi_ffh_address_space_setup,
  50                                                     &ffh_ctx);
  51         if (ACPI_FAILURE(status))
  52                 pr_alert("OperationRegion handler could not be installed\n");
  53 }