sound/soc/soc-acpi.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 //
   3 // soc-apci.c - support for ACPI enumeration.
   4 //
   5 // Copyright (c) 2013-15, Intel Corporation.
   6
   7 #include <sound/soc-acpi.h>
   8
   9 struct snd_soc_acpi_mach *
  10 snd_soc_acpi_find_machine(struct snd_soc_acpi_mach *machines)
  11 {
  12         struct snd_soc_acpi_mach *mach;
  13
  14         for (mach = machines; mach->id[0]; mach++) {
  15                 if (acpi_dev_present(mach->id, NULL, -1)) {
  16                         if (mach->machine_quirk)
  17                                 mach = mach->machine_quirk(mach);
  18                         return mach;
  19                 }
  20         }
  21         return NULL;
  22 }
  23 EXPORT_SYMBOL_GPL(snd_soc_acpi_find_machine);
  24
  25 static acpi_status snd_soc_acpi_find_package(acpi_handle handle, u32 level,
  26                                              void *context, void **ret)
  27 {
  28         struct acpi_device *adev;
  29         acpi_status status = AE_OK;
  30         struct snd_soc_acpi_package_context *pkg_ctx = context;
  31
  32         pkg_ctx->data_valid = false;
  33
  34         if (acpi_bus_get_device(handle, &adev))
  35                 return AE_OK;
  36
  37         if (adev->status.present && adev->status.functional) {
  38                 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
  39                 union acpi_object  *myobj = NULL;
  40
  41                 status = acpi_evaluate_object_typed(handle, pkg_ctx->name,
  42                                                 NULL, &buffer,
  43                                                 ACPI_TYPE_PACKAGE);
  44                 if (ACPI_FAILURE(status))
  45                         return AE_OK;
  46
  47                 myobj = buffer.pointer;
  48                 if (!myobj || myobj->package.count != pkg_ctx->length) {
  49                         kfree(buffer.pointer);
  50                         return AE_OK;
  51                 }
  52
  53                 status = acpi_extract_package(myobj,
  54                                         pkg_ctx->format, pkg_ctx->state);
  55                 if (ACPI_FAILURE(status)) {
  56                         kfree(buffer.pointer);
  57                         return AE_OK;
  58                 }
  59
  60                 kfree(buffer.pointer);
  61                 pkg_ctx->data_valid = true;
  62                 return AE_CTRL_TERMINATE;
  63         }
  64
  65         return AE_OK;
  66 }
  67
  68 bool snd_soc_acpi_find_package_from_hid(const u8 hid[ACPI_ID_LEN],
  69                                 struct snd_soc_acpi_package_context *ctx)
  70 {
  71         acpi_status status;
  72
  73         status = acpi_get_devices(hid, snd_soc_acpi_find_package, ctx, NULL);
  74
  75         if (ACPI_FAILURE(status) || !ctx->data_valid)
  76                 return false;
  77
  78         return true;
  79 }
  80 EXPORT_SYMBOL_GPL(snd_soc_acpi_find_package_from_hid);
  81
  82 struct snd_soc_acpi_mach *snd_soc_acpi_codec_list(void *arg)
  83 {
  84         struct snd_soc_acpi_mach *mach = arg;
  85         struct snd_soc_acpi_codecs *codec_list =
  86                 (struct snd_soc_acpi_codecs *) mach->quirk_data;
  87         int i;
  88
  89         if (mach->quirk_data == NULL)
  90                 return mach;
  91
  92         for (i = 0; i < codec_list->num_codecs; i++) {
  93                 if (!acpi_dev_present(codec_list->codecs[i], NULL, -1))
  94                         return NULL;
  95         }
  96
  97         return mach;
  98 }
  99 EXPORT_SYMBOL_GPL(snd_soc_acpi_codec_list);
 100
 101 MODULE_LICENSE("GPL v2");
 102 MODULE_DESCRIPTION("ALSA SoC ACPI module");