xref: /openbmc/linux/sound/soc/soc-acpi.c (revision 9a29f5fc)
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 = acpi_fetch_acpi_dev(handle);
59 	acpi_status status;
60 	struct snd_soc_acpi_package_context *pkg_ctx = context;
61 
62 	pkg_ctx->data_valid = false;
63 
64 	if (adev && adev->status.present && adev->status.functional) {
65 		struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
66 		union acpi_object  *myobj = NULL;
67 
68 		status = acpi_evaluate_object_typed(handle, pkg_ctx->name,
69 						NULL, &buffer,
70 						ACPI_TYPE_PACKAGE);
71 		if (ACPI_FAILURE(status))
72 			return AE_OK;
73 
74 		myobj = buffer.pointer;
75 		if (!myobj || myobj->package.count != pkg_ctx->length) {
76 			kfree(buffer.pointer);
77 			return AE_OK;
78 		}
79 
80 		status = acpi_extract_package(myobj,
81 					pkg_ctx->format, pkg_ctx->state);
82 		if (ACPI_FAILURE(status)) {
83 			kfree(buffer.pointer);
84 			return AE_OK;
85 		}
86 
87 		kfree(buffer.pointer);
88 		pkg_ctx->data_valid = true;
89 		return AE_CTRL_TERMINATE;
90 	}
91 
92 	return AE_OK;
93 }
94 
95 bool snd_soc_acpi_find_package_from_hid(const u8 hid[ACPI_ID_LEN],
96 				struct snd_soc_acpi_package_context *ctx)
97 {
98 	acpi_status status;
99 
100 	status = acpi_get_devices(hid, snd_soc_acpi_find_package, ctx, NULL);
101 
102 	if (ACPI_FAILURE(status) || !ctx->data_valid)
103 		return false;
104 
105 	return true;
106 }
107 EXPORT_SYMBOL_GPL(snd_soc_acpi_find_package_from_hid);
108 
109 struct snd_soc_acpi_mach *snd_soc_acpi_codec_list(void *arg)
110 {
111 	struct snd_soc_acpi_mach *mach = arg;
112 	struct snd_soc_acpi_codecs *codec_list =
113 		(struct snd_soc_acpi_codecs *) mach->quirk_data;
114 	int i;
115 
116 	if (mach->quirk_data == NULL)
117 		return mach;
118 
119 	for (i = 0; i < codec_list->num_codecs; i++) {
120 		if (!acpi_dev_present(codec_list->codecs[i], NULL, -1))
121 			return NULL;
122 	}
123 
124 	return mach;
125 }
126 EXPORT_SYMBOL_GPL(snd_soc_acpi_codec_list);
127 
128 MODULE_LICENSE("GPL v2");
129 MODULE_DESCRIPTION("ALSA SoC ACPI module");
130