1 /*
2  * Copyright (C) 2014 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15 */
16 
17 #define LOG_TAG "platform_info"
18 #define LOG_NDDEBUG 0
19 
20 #include <errno.h>
21 #include <stdio.h>
22 #include <expat.h>
23 #include <cutils/log.h>
24 #include <audio_hw.h>
25 #include "platform_api.h"
26 #include <platform.h>
27 
28 #define PLATFORM_INFO_XML_PATH      "/system/etc/audio_platform_info.xml"
29 
30 typedef enum {
31     ROOT,
32     ACDB,
33     PCM_ID,
34     BACKEND_NAME,
35 } section_t;
36 
37 typedef void (* section_process_fn)(const XML_Char **attr);
38 
39 static void process_acdb_id(const XML_Char **attr);
40 static void process_pcm_id(const XML_Char **attr);
41 static void process_backend_name(const XML_Char **attr);
42 static void process_root(const XML_Char **attr);
43 
44 static section_process_fn section_table[] = {
45     [ROOT] = process_root,
46     [ACDB] = process_acdb_id,
47     [PCM_ID] = process_pcm_id,
48     [BACKEND_NAME] = process_backend_name,
49 };
50 
51 static section_t section;
52 
53 /*
54  * <audio_platform_info>
55  * <acdb_ids>
56  * <device name="???" acdb_id="???"/>
57  * ...
58  * ...
59  * </acdb_ids>
60  * <backend_names>
61  * <device name="???" backend="???"/>
62  * ...
63  * ...
64  * </backend_names>
65  * <pcm_ids>
66  * <usecase name="???" type="in/out" id="???"/>
67  * ...
68  * ...
69  * </pcm_ids>
70  * </audio_platform_info>
71  */
72 
process_root(const XML_Char ** attr __unused)73 static void process_root(const XML_Char **attr __unused)
74 {
75 }
76 
77 /* mapping from usecase to pcm dev id */
process_pcm_id(const XML_Char ** attr)78 static void process_pcm_id(const XML_Char **attr)
79 {
80     int index;
81 
82     if (strcmp(attr[0], "name") != 0) {
83         ALOGE("%s: 'name' not found, no ACDB ID set!", __func__);
84         goto done;
85     }
86 
87     index = platform_get_usecase_index((char *)attr[1]);
88     if (index < 0) {
89         ALOGE("%s: usecase %s in %s not found!",
90               __func__, attr[1], PLATFORM_INFO_XML_PATH);
91         goto done;
92     }
93 
94     if (strcmp(attr[2], "type") != 0) {
95         ALOGE("%s: usecase type not mentioned", __func__);
96         goto done;
97     }
98 
99     int type = -1;
100 
101     if (!strcasecmp((char *)attr[3], "in")) {
102         type = 1;
103     } else if (!strcasecmp((char *)attr[3], "out")) {
104         type = 0;
105     } else {
106         ALOGE("%s: type must be IN or OUT", __func__);
107         goto done;
108     }
109 
110     if (strcmp(attr[4], "id") != 0) {
111         ALOGE("%s: usecase id not mentioned", __func__);
112         goto done;
113     }
114 
115     int id = atoi((char *)attr[5]);
116 
117     if (platform_set_usecase_pcm_id(index, type, id) < 0) {
118         ALOGE("%s: usecase %s in %s, type %d id %d was not set!",
119               __func__, attr[1], PLATFORM_INFO_XML_PATH, type, id);
120         goto done;
121     }
122 
123 done:
124     return;
125 }
126 
127 /* backend to be used for a device */
process_backend_name(const XML_Char ** attr)128 static void process_backend_name(const XML_Char **attr)
129 {
130     int index;
131 
132     if (strcmp(attr[0], "name") != 0) {
133         ALOGE("%s: 'name' not found, no ACDB ID set!", __func__);
134         goto done;
135     }
136 
137     index = platform_get_snd_device_index((char *)attr[1]);
138     if (index < 0) {
139         ALOGE("%s: Device %s in %s not found, no ACDB ID set!",
140               __func__, attr[1], PLATFORM_INFO_XML_PATH);
141         goto done;
142     }
143 
144     if (strcmp(attr[2], "backend") != 0) {
145         ALOGE("%s: Device %s in %s has no backed set!",
146               __func__, attr[1], PLATFORM_INFO_XML_PATH);
147         goto done;
148     }
149 
150     if (platform_set_snd_device_backend(index, attr[3]) < 0) {
151         ALOGE("%s: Device %s in %s, backend %s was not set!",
152               __func__, attr[1], PLATFORM_INFO_XML_PATH, attr[3]);
153         goto done;
154     }
155 
156 done:
157     return;
158 }
159 
process_acdb_id(const XML_Char ** attr)160 static void process_acdb_id(const XML_Char **attr)
161 {
162     int index;
163 
164     if (strcmp(attr[0], "name") != 0) {
165         ALOGE("%s: 'name' not found, no ACDB ID set!", __func__);
166         goto done;
167     }
168 
169     index = platform_get_snd_device_index((char *)attr[1]);
170     if (index < 0) {
171         ALOGE("%s: Device %s in %s not found, no ACDB ID set!",
172               __func__, attr[1], PLATFORM_INFO_XML_PATH);
173         goto done;
174     }
175 
176     if (strcmp(attr[2], "acdb_id") != 0) {
177         ALOGE("%s: Device %s in %s has no acdb_id, no ACDB ID set!",
178               __func__, attr[1], PLATFORM_INFO_XML_PATH);
179         goto done;
180     }
181 
182     if (platform_set_snd_device_acdb_id(index, atoi((char *)attr[3])) < 0) {
183         ALOGE("%s: Device %s in %s, ACDB ID %d was not set!",
184               __func__, attr[1], PLATFORM_INFO_XML_PATH, atoi((char *)attr[3]));
185         goto done;
186     }
187 
188 done:
189     return;
190 }
191 
start_tag(void * userdata __unused,const XML_Char * tag_name,const XML_Char ** attr)192 static void start_tag(void *userdata __unused, const XML_Char *tag_name,
193                       const XML_Char **attr)
194 {
195     const XML_Char              *attr_name = NULL;
196     const XML_Char              *attr_value = NULL;
197     unsigned int                i;
198 
199     if (strcmp(tag_name, "acdb_ids") == 0) {
200         section = ACDB;
201     } else if (strcmp(tag_name, "pcm_ids") == 0) {
202         section = PCM_ID;
203     } else if (strcmp(tag_name, "backend_names") == 0) {
204         section = BACKEND_NAME;
205     } else if (strcmp(tag_name, "device") == 0) {
206         if ((section != ACDB) && (section != BACKEND_NAME)) {
207             ALOGE("device tag only supported for acdb/backend names");
208             return;
209         }
210 
211         /* call into process function for the current section */
212         section_process_fn fn = section_table[section];
213         fn(attr);
214     } else if (strcmp(tag_name, "usecase") == 0) {
215         if (section != PCM_ID) {
216             ALOGE("usecase tag only supported with PCM_ID section");
217             return;
218         }
219 
220         section_process_fn fn = section_table[PCM_ID];
221         fn(attr);
222     }
223 
224     return;
225 }
226 
end_tag(void * userdata __unused,const XML_Char * tag_name)227 static void end_tag(void *userdata __unused, const XML_Char *tag_name)
228 {
229     if (strcmp(tag_name, "acdb_ids") == 0) {
230         section = ROOT;
231     } else if (strcmp(tag_name, "pcm_ids") == 0) {
232         section = ROOT;
233     } else if (strcmp(tag_name, "backend_names") == 0) {
234         section = ROOT;
235     }
236 }
237 
platform_info_init(void)238 int platform_info_init(void)
239 {
240     XML_Parser      parser;
241     FILE            *file;
242     int             ret = 0;
243     int             bytes_read;
244     void            *buf;
245     static const uint32_t kBufSize = 1024;
246 
247     section = ROOT;
248 
249     file = fopen(PLATFORM_INFO_XML_PATH, "r");
250     if (!file) {
251         ALOGD("%s: Failed to open %s, using defaults.",
252             __func__, PLATFORM_INFO_XML_PATH);
253         ret = -ENODEV;
254         goto done;
255     }
256 
257     parser = XML_ParserCreate(NULL);
258     if (!parser) {
259         ALOGE("%s: Failed to create XML parser!", __func__);
260         ret = -ENODEV;
261         goto err_close_file;
262     }
263 
264     XML_SetElementHandler(parser, start_tag, end_tag);
265 
266     while (1) {
267         buf = XML_GetBuffer(parser, kBufSize);
268         if (buf == NULL) {
269             ALOGE("%s: XML_GetBuffer failed", __func__);
270             ret = -ENOMEM;
271             goto err_free_parser;
272         }
273 
274         bytes_read = fread(buf, 1, kBufSize, file);
275         if (bytes_read < 0) {
276             ALOGE("%s: fread failed, bytes read = %d", __func__, bytes_read);
277              ret = bytes_read;
278             goto err_free_parser;
279         }
280 
281         if (XML_ParseBuffer(parser, bytes_read,
282                             bytes_read == 0) == XML_STATUS_ERROR) {
283             ALOGE("%s: XML_ParseBuffer failed, for %s",
284                 __func__, PLATFORM_INFO_XML_PATH);
285             ret = -EINVAL;
286             goto err_free_parser;
287         }
288 
289         if (bytes_read == 0)
290             break;
291     }
292 
293 err_free_parser:
294     XML_ParserFree(parser);
295 err_close_file:
296     fclose(file);
297 done:
298     return ret;
299 }
300