sound/soc/soc-acpi.c

   1 /*
   2  * soc-apci.c - support for ACPI enumeration.
   3  *
   4  * Copyright (c) 2013-15, Intel Corporation.
   5  *
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms and conditions of the GNU General Public License,
   9  * version 2, as published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * more details.
  15  */
  16
  17 #include <sound/soc-acpi.h>
  18
  19 struct snd_soc_acpi_mach *
  20 snd_soc_acpi_find_machine(struct snd_soc_acpi_mach *machines)
  21 {
  22         struct snd_soc_acpi_mach *mach;
  23
  24         for (mach = machines; mach->id[0]; mach++) {
  25                 if (acpi_dev_present(mach->id, NULL, -1)) {
  26                         if (mach->machine_quirk)
  27                                 mach = mach->machine_quirk(mach);
  28                         return mach;
  29                 }
  30         }
  31         return NULL;
  32 }
  33 EXPORT_SYMBOL_GPL(snd_soc_acpi_find_machine);
  34
  35 static acpi_status snd_soc_acpi_find_package(acpi_handle handle, u32 level,
  36                                              void *context, void **ret)
  37 {
  38         struct acpi_device *adev;
  39         acpi_status status = AE_OK;
  40         struct snd_soc_acpi_package_context *pkg_ctx = context;
  41
  42         pkg_ctx->data_valid = false;
  43
  44         if (acpi_bus_get_device(handle, &adev))
  45                 return AE_OK;
  46
  47         if (adev->status.present && adev->status.functional) {
  48                 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
  49                 union acpi_object  *myobj = NULL;
  50
  51                 status = acpi_evaluate_object_typed(handle, pkg_ctx->name,
  52                                                 NULL, &buffer,
  53                                                 ACPI_TYPE_PACKAGE);
  54                 if (ACPI_FAILURE(status))
  55                         return AE_OK;
  56
  57                 myobj = buffer.pointer;
  58                 if (!myobj || myobj->package.count != pkg_ctx->length) {
  59                         kfree(buffer.pointer);
  60                         return AE_OK;
  61                 }
  62
  63                 status = acpi_extract_package(myobj,
  64                                         pkg_ctx->format, pkg_ctx->state);
  65                 if (ACPI_FAILURE(status)) {
  66                         kfree(buffer.pointer);
  67                         return AE_OK;
  68                 }
  69
  70                 kfree(buffer.pointer);
  71                 pkg_ctx->data_valid = true;
  72                 return AE_CTRL_TERMINATE;
  73         }
  74
  75         return AE_OK;
  76 }
  77
  78 bool snd_soc_acpi_find_package_from_hid(const u8 hid[ACPI_ID_LEN],
  79                                 struct snd_soc_acpi_package_context *ctx)
  80 {
  81         acpi_status status;
  82
  83         status = acpi_get_devices(hid, snd_soc_acpi_find_package, ctx, NULL);
  84
  85         if (ACPI_FAILURE(status) || !ctx->data_valid)
  86                 return false;
  87
  88         return true;
  89 }
  90 EXPORT_SYMBOL_GPL(snd_soc_acpi_find_package_from_hid);
  91
  92 struct snd_soc_acpi_mach *snd_soc_acpi_codec_list(void *arg)
  93 {
  94         struct snd_soc_acpi_mach *mach = arg;
  95         struct snd_soc_acpi_codecs *codec_list =
  96                 (struct snd_soc_acpi_codecs *) mach->quirk_data;
  97         int i;
  98
  99         if (mach->quirk_data == NULL)
 100                 return mach;
 101
 102         for (i = 0; i < codec_list->num_codecs; i++) {
 103                 if (!acpi_dev_present(codec_list->codecs[i], NULL, -1))
 104                         return NULL;
 105         }
 106
 107         return mach;
 108 }
 109 EXPORT_SYMBOL_GPL(snd_soc_acpi_codec_list);
 110
 111 MODULE_LICENSE("GPL v2");
 112 MODULE_DESCRIPTION("ALSA SoC ACPI module");