xref: /openbmc/linux/sound/soc/soc-acpi.c (revision e2c75e76)
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");
113