xref: /openbmc/linux/sound/soc/soc-acpi.c (revision d9fd5a71)
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 = 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 
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");
111