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 <linux/export.h>
   8 #include <linux/module.h>
   9 #include <sound/soc-acpi.h>
  10
  11 struct snd_soc_acpi_mach *
  12 snd_soc_acpi_find_machine(struct snd_soc_acpi_mach *machines)
  13 {
  14         struct snd_soc_acpi_mach *mach;
  15         struct snd_soc_acpi_mach *mach_alt;
  16
  17         for (mach = machines; mach->id[0]; mach++) {
  18                 if (acpi_dev_present(mach->id, NULL, -1)) {
  19                         if (mach->machine_quirk) {
  20                                 mach_alt = mach->machine_quirk(mach);
  21                                 if (!mach_alt)
  22                                         continue; /* not full match, ignore */
  23                                 mach = mach_alt;
  24                         }
  25
  26                         return mach;
  27                 }
  28         }
  29         return NULL;
  30 }
  31 EXPORT_SYMBOL_GPL(snd_soc_acpi_find_machine);
  32
  33 static acpi_status snd_soc_acpi_find_package(acpi_handle handle, u32 level,
  34                                              void *context, void **ret)
  35 {
  36         struct acpi_device *adev;
  37         acpi_status status;
  38         struct snd_soc_acpi_package_context *pkg_ctx = context;
  39
  40         pkg_ctx->data_valid = false;
  41
  42         if (acpi_bus_get_device(handle, &adev))
  43                 return AE_OK;
  44
  45         if (adev->status.present && adev->status.functional) {
  46                 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
  47                 union acpi_object  *myobj = NULL;
  48
  49                 status = acpi_evaluate_object_typed(handle, pkg_ctx->name,
  50                                                 NULL, &buffer,
  51                                                 ACPI_TYPE_PACKAGE);
  52                 if (ACPI_FAILURE(status))
  53                         return AE_OK;
  54
  55                 myobj = buffer.pointer;
  56                 if (!myobj || myobj->package.count != pkg_ctx->length) {
  57                         kfree(buffer.pointer);
  58                         return AE_OK;
  59                 }
  60
  61                 status = acpi_extract_package(myobj,
  62                                         pkg_ctx->format, pkg_ctx->state);
  63                 if (ACPI_FAILURE(status)) {
  64                         kfree(buffer.pointer);
  65                         return AE_OK;
  66                 }
  67
  68                 kfree(buffer.pointer);
  69                 pkg_ctx->data_valid = true;
  70                 return AE_CTRL_TERMINATE;
  71         }
  72
  73         return AE_OK;
  74 }
  75
  76 bool snd_soc_acpi_find_package_from_hid(const u8 hid[ACPI_ID_LEN],
  77                                 struct snd_soc_acpi_package_context *ctx)
  78 {
  79         acpi_status status;
  80
  81         status = acpi_get_devices(hid, snd_soc_acpi_find_package, ctx, NULL);
  82
  83         if (ACPI_FAILURE(status) || !ctx->data_valid)
  84                 return false;
  85
  86         return true;
  87 }
  88 EXPORT_SYMBOL_GPL(snd_soc_acpi_find_package_from_hid);
  89
  90 struct snd_soc_acpi_mach *snd_soc_acpi_codec_list(void *arg)
  91 {
  92         struct snd_soc_acpi_mach *mach = arg;
  93         struct snd_soc_acpi_codecs *codec_list =
  94                 (struct snd_soc_acpi_codecs *) mach->quirk_data;
  95         int i;
  96
  97         if (mach->quirk_data == NULL)
  98                 return mach;
  99
 100         for (i = 0; i < codec_list->num_codecs; i++) {
 101                 if (!acpi_dev_present(codec_list->codecs[i], NULL, -1))
 102                         return NULL;
 103         }
 104
 105         return mach;
 106 }
 107 EXPORT_SYMBOL_GPL(snd_soc_acpi_codec_list);
 108
 109 MODULE_LICENSE("GPL v2");
 110 MODULE_DESCRIPTION("ALSA SoC ACPI module");