xref: /kernel/linux/linux-5.10/sound/soc/soc-acpi.c (revision 8c2ecf20) 
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
11struct snd_soc_acpi_mach *
12snd_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}
31EXPORT_SYMBOL_GPL(snd_soc_acpi_find_machine);
32
33static 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 = AE_OK;
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
76bool 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}
88EXPORT_SYMBOL_GPL(snd_soc_acpi_find_package_from_hid);
89
90struct 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}
107EXPORT_SYMBOL_GPL(snd_soc_acpi_codec_list);
108
109MODULE_LICENSE("GPL v2");
110MODULE_DESCRIPTION("ALSA SoC ACPI module");
111