xref: /openbmc/linux/sound/soc/soc-acpi.c (revision 6e10e219)
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");
133