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 static bool snd_soc_acpi_id_present(struct snd_soc_acpi_mach *machine)
  12 {
  13         const struct snd_soc_acpi_codecs *comp_ids = machine->comp_ids;
  14         int i;
  15
  16         if (machine->id[0]) {
  17                 if (acpi_dev_present(machine->id, NULL, -1))
  18                         return true;
  19         }
  20
  21         if (comp_ids) {
  22                 for (i = 0; i < comp_ids->num_codecs; i++) {
  23                         if (acpi_dev_present(comp_ids->codecs[i], NULL, -1)) {
  24                                 strscpy(machine->id, comp_ids->codecs[i], ACPI_ID_LEN);
  25                                 return true;
  26                         }
  27                 }
  28         }
  29
  30         return false;
  31 }
  32
  33 struct snd_soc_acpi_mach *
  34 snd_soc_acpi_find_machine(struct snd_soc_acpi_mach *machines)
  35 {
  36         struct snd_soc_acpi_mach *mach;
  37         struct snd_soc_acpi_mach *mach_alt;
  38
  39         for (mach = machines; mach->id[0] || mach->comp_ids; mach++) {
  40                 if (snd_soc_acpi_id_present(mach)) {
  41                         if (mach->machine_quirk) {
  42                                 mach_alt = mach->machine_quirk(mach);
  43                                 if (!mach_alt)
  44                                         continue; /* not full match, ignore */
  45                                 mach = mach_alt;
  46                         }
  47
  48                         return mach;
  49                 }
  50         }
  51         return NULL;
  52 }
  53 EXPORT_SYMBOL_GPL(snd_soc_acpi_find_machine);
  54
  55 static acpi_status snd_soc_acpi_find_package(acpi_handle handle, u32 level,
  56                                              void *context, void **ret)
  57 {
  58         struct acpi_device *adev;
  59         acpi_status status;
  60         struct snd_soc_acpi_package_context *pkg_ctx = context;
  61
  62         pkg_ctx->data_valid = false;
  63
  64         if (acpi_bus_get_device(handle, &adev))
  65                 return AE_OK;
  66
  67         if (adev->status.present && adev->status.functional) {
  68                 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
  69                 union acpi_object  *myobj = NULL;
  70
  71                 status = acpi_evaluate_object_typed(handle, pkg_ctx->name,
  72                                                 NULL, &buffer,
  73                                                 ACPI_TYPE_PACKAGE);
  74                 if (ACPI_FAILURE(status))
  75                         return AE_OK;
  76
  77                 myobj = buffer.pointer;
  78                 if (!myobj || myobj->package.count != pkg_ctx->length) {
  79                         kfree(buffer.pointer);
  80                         return AE_OK;
  81                 }
  82
  83                 status = acpi_extract_package(myobj,
  84                                         pkg_ctx->format, pkg_ctx->state);
  85                 if (ACPI_FAILURE(status)) {
  86                         kfree(buffer.pointer);
  87                         return AE_OK;
  88                 }
  89
  90                 kfree(buffer.pointer);
  91                 pkg_ctx->data_valid = true;
  92                 return AE_CTRL_TERMINATE;
  93         }
  94
  95         return AE_OK;
  96 }
  97
  98 bool snd_soc_acpi_find_package_from_hid(const u8 hid[ACPI_ID_LEN],
  99                                 struct snd_soc_acpi_package_context *ctx)
 100 {
 101         acpi_status status;
 102
 103         status = acpi_get_devices(hid, snd_soc_acpi_find_package, ctx, NULL);
 104
 105         if (ACPI_FAILURE(status) || !ctx->data_valid)
 106                 return false;
 107
 108         return true;
 109 }
 110 EXPORT_SYMBOL_GPL(snd_soc_acpi_find_package_from_hid);
 111
 112 struct snd_soc_acpi_mach *snd_soc_acpi_codec_list(void *arg)
 113 {
 114         struct snd_soc_acpi_mach *mach = arg;
 115         struct snd_soc_acpi_codecs *codec_list =
 116                 (struct snd_soc_acpi_codecs *) mach->quirk_data;
 117         int i;
 118
 119         if (mach->quirk_data == NULL)
 120                 return mach;
 121
 122         for (i = 0; i < codec_list->num_codecs; i++) {
 123                 if (!acpi_dev_present(codec_list->codecs[i], NULL, -1))
 124                         return NULL;
 125         }
 126
 127         return mach;
 128 }
 129 EXPORT_SYMBOL_GPL(snd_soc_acpi_codec_list);
 130
 131 MODULE_LICENSE("GPL v2");
 132 MODULE_DESCRIPTION("ALSA SoC ACPI module");