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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 "alsa_device_profile"
18 /*#define LOG_NDEBUG 0*/
19 /*#define LOG_PCM_PARAMS 0*/
20 
21 #include <errno.h>
22 #include <inttypes.h>
23 #include <stdint.h>
24 #include <stdlib.h>
25 
26 #include <log/log.h>
27 
28 #include "alsa_device_profile.h"
29 #include "format.h"
30 #include "logging.h"
31 
32 #define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
33 
34 /*TODO - Evaluate if this value should/can be retrieved from a device-specific property */
35 #define BUFF_DURATION_MS   5
36 
37 #define DEFAULT_PERIOD_SIZE 1024
38 
39 static const char * const format_string_map[] = {
40     "AUDIO_FORMAT_PCM_16_BIT",      /* "PCM_FORMAT_S16_LE", */
41     "AUDIO_FORMAT_PCM_32_BIT",      /* "PCM_FORMAT_S32_LE", */
42     "AUDIO_FORMAT_PCM_8_BIT",       /* "PCM_FORMAT_S8", */
43     "AUDIO_FORMAT_PCM_8_24_BIT",    /* "PCM_FORMAT_S24_LE", */
44     "AUDIO_FORMAT_PCM_24_BIT_PACKED"/* "PCM_FORMAT_S24_3LE" */
45 };
46 
47 static const unsigned const format_byte_size_map[] = {
48     2, /* PCM_FORMAT_S16_LE */
49     4, /* PCM_FORMAT_S32_LE */
50     1, /* PCM_FORMAT_S8 */
51     4, /* PCM_FORMAT_S24_LE */
52     3, /* PCM_FORMAT_S24_3LE */
53 };
54 
55 extern int8_t const pcm_format_value_map[50];
56 
57 /* sort these highest -> lowest (to default to best quality) */
58 static const unsigned std_sample_rates[] =
59     {48000, 44100, 32000, 24000, 22050, 16000, 12000, 11025, 8000};
60 
profile_reset(alsa_device_profile * profile)61 static void profile_reset(alsa_device_profile* profile)
62 {
63     profile->card = profile->device = -1;
64 
65     /* Fill the attribute arrays with invalid values */
66     size_t index;
67     for (index = 0; index < ARRAY_SIZE(profile->formats); index++) {
68         profile->formats[index] = PCM_FORMAT_INVALID;
69     }
70 
71     for (index = 0; index < ARRAY_SIZE(profile->sample_rates); index++) {
72         profile->sample_rates[index] = 0;
73     }
74 
75     for (index = 0; index < ARRAY_SIZE(profile->channel_counts); index++) {
76         profile->channel_counts[index] = 0;
77     }
78 
79     profile->min_period_size = profile->max_period_size = 0;
80     profile->min_channel_count = profile->max_channel_count = DEFAULT_CHANNEL_COUNT;
81 
82     profile->is_valid = false;
83 }
84 
profile_init(alsa_device_profile * profile,int direction)85 void profile_init(alsa_device_profile* profile, int direction)
86 {
87     profile->direction = direction;
88     profile_reset(profile);
89 }
90 
profile_is_initialized(alsa_device_profile * profile)91 bool profile_is_initialized(alsa_device_profile* profile)
92 {
93     return profile->card >= 0 && profile->device >= 0;
94 }
95 
profile_is_valid(alsa_device_profile * profile)96 bool profile_is_valid(alsa_device_profile* profile) {
97     return profile->is_valid;
98 }
99 
profile_is_cached_for(alsa_device_profile * profile,int card,int device)100 bool profile_is_cached_for(alsa_device_profile* profile, int card, int device) {
101     return card == profile->card && device == profile->device;
102 }
103 
profile_decache(alsa_device_profile * profile)104 void profile_decache(alsa_device_profile* profile) {
105     profile_reset(profile);
106 }
107 
108 /*
109  * Returns the supplied value rounded up to the next even multiple of 16
110  */
round_to_16_mult(unsigned int size)111 static unsigned int round_to_16_mult(unsigned int size)
112 {
113     return (size + 15) & ~15;   // 0xFFFFFFF0;
114 }
115 
116 /*
117  * Returns the system defined minimum period size based on the supplied sample rate.
118  */
profile_calc_min_period_size(alsa_device_profile * profile,unsigned sample_rate)119 unsigned profile_calc_min_period_size(alsa_device_profile* profile, unsigned sample_rate)
120 {
121     ALOGV("profile_calc_min_period_size(%p, rate:%d)", profile, sample_rate);
122     if (profile == NULL) {
123         return DEFAULT_PERIOD_SIZE;
124     } else {
125         unsigned num_sample_frames = (sample_rate * BUFF_DURATION_MS) / 1000;
126         if (num_sample_frames < profile->min_period_size) {
127             num_sample_frames = profile->min_period_size;
128         }
129         return round_to_16_mult(num_sample_frames) * 2;
130     }
131 }
132 
profile_get_period_size(alsa_device_profile * profile,unsigned sample_rate)133 unsigned int profile_get_period_size(alsa_device_profile* profile, unsigned sample_rate)
134 {
135     // return profile->default_config.period_size;
136     unsigned int period_size = profile_calc_min_period_size(profile, sample_rate);
137     ALOGV("profile_get_period_size(rate:%d) = %d", sample_rate, period_size);
138     return period_size;
139 }
140 
141 /*
142  * Sample Rate
143  */
profile_get_default_sample_rate(alsa_device_profile * profile)144 unsigned profile_get_default_sample_rate(alsa_device_profile* profile)
145 {
146     /*
147      * TODO this won't be right in general. we should store a preferred rate as we are scanning.
148      * But right now it will return the highest rate, which may be correct.
149      */
150     return profile_is_valid(profile) ? profile->sample_rates[0] : DEFAULT_SAMPLE_RATE;
151 }
152 
profile_is_sample_rate_valid(alsa_device_profile * profile,unsigned rate)153 bool profile_is_sample_rate_valid(alsa_device_profile* profile, unsigned rate)
154 {
155     if (profile_is_valid(profile)) {
156         size_t index;
157         for (index = 0; profile->sample_rates[index] != 0; index++) {
158             if (profile->sample_rates[index] == rate) {
159                 return true;
160             }
161         }
162 
163         return false;
164     } else {
165         return rate == DEFAULT_SAMPLE_RATE;
166     }
167 }
168 
169 /*
170  * Format
171  */
profile_get_default_format(alsa_device_profile * profile)172 enum pcm_format profile_get_default_format(alsa_device_profile* profile)
173 {
174     /*
175      * TODO this won't be right in general. we should store a preferred format as we are scanning.
176      */
177     return profile_is_valid(profile) ? profile->formats[0] : DEFAULT_SAMPLE_FORMAT;
178 }
179 
profile_is_format_valid(alsa_device_profile * profile,enum pcm_format fmt)180 bool profile_is_format_valid(alsa_device_profile* profile, enum pcm_format fmt) {
181     if (profile_is_valid(profile)) {
182         size_t index;
183         for (index = 0; profile->formats[index] != PCM_FORMAT_INVALID; index++) {
184             if (profile->formats[index] == fmt) {
185                 return true;
186             }
187         }
188 
189         return false;
190     } else {
191         return fmt == DEFAULT_SAMPLE_FORMAT;
192     }
193 }
194 
195 /*
196  * Channels
197  */
profile_get_default_channel_count(alsa_device_profile * profile)198 unsigned profile_get_default_channel_count(alsa_device_profile* profile)
199 {
200     return profile_is_valid(profile) ? profile->channel_counts[0] : DEFAULT_CHANNEL_COUNT;
201 }
202 
profile_is_channel_count_valid(alsa_device_profile * profile,unsigned count)203 bool profile_is_channel_count_valid(alsa_device_profile* profile, unsigned count)
204 {
205     if (profile_is_initialized(profile)) {
206         return count >= profile->min_channel_count && count <= profile->max_channel_count;
207     } else {
208         return count == DEFAULT_CHANNEL_COUNT;
209     }
210 }
211 
profile_test_sample_rate(alsa_device_profile * profile,unsigned rate)212 static bool profile_test_sample_rate(alsa_device_profile* profile, unsigned rate)
213 {
214     struct pcm_config config = profile->default_config;
215     config.rate = rate;
216 
217     bool works = false; /* let's be pessimistic */
218     struct pcm * pcm = pcm_open(profile->card, profile->device,
219                                 profile->direction, &config);
220 
221     if (pcm != NULL) {
222         works = pcm_is_ready(pcm);
223         pcm_close(pcm);
224     }
225 
226     return works;
227 }
228 
profile_enum_sample_rates(alsa_device_profile * profile,unsigned min,unsigned max)229 static unsigned profile_enum_sample_rates(alsa_device_profile* profile, unsigned min, unsigned max)
230 {
231     unsigned num_entries = 0;
232     unsigned index;
233 
234     for (index = 0; index < ARRAY_SIZE(std_sample_rates) &&
235                     num_entries < ARRAY_SIZE(profile->sample_rates) - 1;
236          index++) {
237         if (std_sample_rates[index] >= min && std_sample_rates[index] <= max
238                 && profile_test_sample_rate(profile, std_sample_rates[index])) {
239             profile->sample_rates[num_entries++] = std_sample_rates[index];
240         }
241     }
242 
243     return num_entries; /* return # of supported rates */
244 }
245 
profile_enum_sample_formats(alsa_device_profile * profile,struct pcm_mask * mask)246 static unsigned profile_enum_sample_formats(alsa_device_profile* profile, struct pcm_mask * mask)
247 {
248     const int num_slots = ARRAY_SIZE(mask->bits);
249     const int bits_per_slot = sizeof(mask->bits[0]) * 8;
250 
251     const int table_size = ARRAY_SIZE(pcm_format_value_map);
252 
253     int slot_index, bit_index, table_index;
254     table_index = 0;
255     int num_written = 0;
256     for (slot_index = 0; slot_index < num_slots && table_index < table_size;
257             slot_index++) {
258         unsigned bit_mask = 1;
259         for (bit_index = 0;
260                 bit_index < bits_per_slot && table_index < table_size;
261                 bit_index++) {
262             if ((mask->bits[slot_index] & bit_mask) != 0) {
263                 enum pcm_format format = pcm_format_value_map[table_index];
264                 /* Never return invalid (unrecognized) or 8-bit */
265                 if (format != PCM_FORMAT_INVALID && format != PCM_FORMAT_S8) {
266                     profile->formats[num_written++] = format;
267                     if (num_written == ARRAY_SIZE(profile->formats) - 1) {
268                         /* leave at least one PCM_FORMAT_INVALID at the end */
269                         return num_written;
270                     }
271                 }
272             }
273             bit_mask <<= 1;
274             table_index++;
275         }
276     }
277 
278     return num_written;
279 }
280 
profile_enum_channel_counts(alsa_device_profile * profile,unsigned min,unsigned max)281 static unsigned profile_enum_channel_counts(alsa_device_profile* profile, unsigned min, unsigned max)
282 {
283     static const unsigned std_channel_counts[] = {8, 4, 2, 1};
284 
285     unsigned num_counts = 0;
286     unsigned index;
287     /* TODO write a profile_test_channel_count() */
288     /* Ensure there is at least one invalid channel count to terminate the channel counts array */
289     for (index = 0; index < ARRAY_SIZE(std_channel_counts) &&
290                     num_counts < ARRAY_SIZE(profile->channel_counts) - 1;
291          index++) {
292         /* TODO Do we want a channel counts test? */
293         if (std_channel_counts[index] >= min && std_channel_counts[index] <= max /* &&
294             profile_test_channel_count(profile, channel_counts[index])*/) {
295             profile->channel_counts[num_counts++] = std_channel_counts[index];
296         }
297     }
298 
299     return num_counts; /* return # of supported counts */
300 }
301 
302 /*
303  * Reads and decodes configuration info from the specified ALSA card/device.
304  */
read_alsa_device_config(alsa_device_profile * profile,struct pcm_config * config)305 static int read_alsa_device_config(alsa_device_profile * profile, struct pcm_config * config)
306 {
307     ALOGV("usb:audio_hw - read_alsa_device_config(c:%d d:%d t:0x%X)",
308           profile->card, profile->device, profile->direction);
309 
310     if (profile->card < 0 || profile->device < 0) {
311         return -EINVAL;
312     }
313 
314     struct pcm_params * alsa_hw_params =
315         pcm_params_get(profile->card, profile->device, profile->direction);
316     if (alsa_hw_params == NULL) {
317         return -EINVAL;
318     }
319 
320     profile->min_period_size = pcm_params_get_min(alsa_hw_params, PCM_PARAM_PERIOD_SIZE);
321     profile->max_period_size = pcm_params_get_max(alsa_hw_params, PCM_PARAM_PERIOD_SIZE);
322 
323     profile->min_channel_count = pcm_params_get_min(alsa_hw_params, PCM_PARAM_CHANNELS);
324     profile->max_channel_count = pcm_params_get_max(alsa_hw_params, PCM_PARAM_CHANNELS);
325 
326     int ret = 0;
327 
328     /*
329      * This Logging will be useful when testing new USB devices.
330      */
331 #ifdef LOG_PCM_PARAMS
332     log_pcm_params(alsa_hw_params);
333 #endif
334 
335     config->channels = pcm_params_get_min(alsa_hw_params, PCM_PARAM_CHANNELS);
336     config->rate = pcm_params_get_min(alsa_hw_params, PCM_PARAM_RATE);
337     config->period_size = profile_calc_min_period_size(profile, config->rate);
338     config->period_count = pcm_params_get_min(alsa_hw_params, PCM_PARAM_PERIODS);
339     config->format = get_pcm_format_for_mask(pcm_params_get_mask(alsa_hw_params, PCM_PARAM_FORMAT));
340 #ifdef LOG_PCM_PARAMS
341     log_pcm_config(config, "read_alsa_device_config");
342 #endif
343     if (config->format == PCM_FORMAT_INVALID) {
344         ret = -EINVAL;
345     }
346 
347     pcm_params_free(alsa_hw_params);
348 
349     return ret;
350 }
351 
profile_read_device_info(alsa_device_profile * profile)352 bool profile_read_device_info(alsa_device_profile* profile)
353 {
354     if (!profile_is_initialized(profile)) {
355         return false;
356     }
357 
358     /* let's get some defaults */
359     read_alsa_device_config(profile, &profile->default_config);
360     ALOGV("default_config chans:%d rate:%d format:%d count:%d size:%d",
361           profile->default_config.channels, profile->default_config.rate,
362           profile->default_config.format, profile->default_config.period_count,
363           profile->default_config.period_size);
364 
365     struct pcm_params * alsa_hw_params = pcm_params_get(profile->card,
366                                                         profile->device,
367                                                         profile->direction);
368     if (alsa_hw_params == NULL) {
369         return false;
370     }
371 
372     /* Formats */
373     struct pcm_mask * format_mask = pcm_params_get_mask(alsa_hw_params, PCM_PARAM_FORMAT);
374     profile_enum_sample_formats(profile, format_mask);
375 
376     /* Channels */
377     profile_enum_channel_counts(
378             profile, pcm_params_get_min(alsa_hw_params, PCM_PARAM_CHANNELS),
379             pcm_params_get_max(alsa_hw_params, PCM_PARAM_CHANNELS));
380 
381     /* Sample Rates */
382     profile_enum_sample_rates(
383             profile, pcm_params_get_min(alsa_hw_params, PCM_PARAM_RATE),
384             pcm_params_get_max(alsa_hw_params, PCM_PARAM_RATE));
385 
386     profile->is_valid = true;
387 
388     return true;
389 }
390 
profile_get_sample_rate_strs(alsa_device_profile * profile)391 char * profile_get_sample_rate_strs(alsa_device_profile* profile)
392 {
393     char buffer[128];
394     buffer[0] = '\0';
395     int buffSize = ARRAY_SIZE(buffer);
396 
397     char numBuffer[32];
398 
399     int numEntries = 0;
400     unsigned index;
401     for (index = 0; profile->sample_rates[index] != 0; index++) {
402         if (numEntries++ != 0) {
403             strncat(buffer, "|", buffSize);
404         }
405         snprintf(numBuffer, sizeof(numBuffer), "%u", profile->sample_rates[index]);
406         strncat(buffer, numBuffer, buffSize);
407     }
408 
409     return strdup(buffer);
410 }
411 
profile_get_format_strs(alsa_device_profile * profile)412 char * profile_get_format_strs(alsa_device_profile* profile)
413 {
414     /* TODO remove this hack when we have support for input in non PCM16 formats */
415     if (profile->direction == PCM_IN) {
416         return strdup("AUDIO_FORMAT_PCM_16_BIT");
417     }
418 
419     char buffer[128];
420     buffer[0] = '\0';
421     int buffSize = ARRAY_SIZE(buffer);
422 
423     int numEntries = 0;
424     unsigned index = 0;
425     for (index = 0; profile->formats[index] != PCM_FORMAT_INVALID; index++) {
426         if (numEntries++ != 0) {
427             strncat(buffer, "|", buffSize);
428         }
429         strncat(buffer, format_string_map[profile->formats[index]], buffSize);
430     }
431 
432     return strdup(buffer);
433 }
434 
profile_get_channel_count_strs(alsa_device_profile * profile)435 char * profile_get_channel_count_strs(alsa_device_profile* profile)
436 {
437     static const char * const out_chans_strs[] = {
438         /* 0 */"AUDIO_CHANNEL_NONE", /* will never be taken as this is a terminator */
439         /* 1 */"AUDIO_CHANNEL_OUT_MONO",
440         /* 2 */"AUDIO_CHANNEL_OUT_STEREO",
441         /* 3 */ /* "AUDIO_CHANNEL_OUT_STEREO|AUDIO_CHANNEL_OUT_FRONT_CENTER" */ NULL,
442         /* 4 */"AUDIO_CHANNEL_OUT_QUAD",
443         /* 5 */ /* "AUDIO_CHANNEL_OUT_QUAD|AUDIO_CHANNEL_OUT_FRONT_CENTER" */ NULL,
444         /* 6 */"AUDIO_CHANNEL_OUT_5POINT1",
445         /* 7 */ /* "AUDIO_CHANNEL_OUT_5POINT1|AUDIO_CHANNEL_OUT_BACK_CENTER" */ NULL,
446         /* 8 */"AUDIO_CHANNEL_OUT_7POINT1",
447         /* channel counts greater than this not considered */
448     };
449 
450     static const char * const in_chans_strs[] = {
451         /* 0 */"AUDIO_CHANNEL_NONE", /* will never be taken as this is a terminator */
452         /* 1 */"AUDIO_CHANNEL_IN_MONO",
453         /* 2 */"AUDIO_CHANNEL_IN_STEREO",
454         /* channel counts greater than this not considered */
455     };
456 
457     const bool isOutProfile = profile->direction == PCM_OUT;
458 
459     const char * const * const names_array = isOutProfile ? out_chans_strs : in_chans_strs;
460     const size_t names_size = isOutProfile ? ARRAY_SIZE(out_chans_strs)
461             : ARRAY_SIZE(in_chans_strs);
462 
463     char buffer[256]; /* caution, may need to be expanded */
464     buffer[0] = '\0';
465     const int buffer_size = ARRAY_SIZE(buffer);
466     int num_entries = 0;
467     /* We currently support MONO and STEREO, and always report STEREO but some (many)
468      * USB Audio Devices may only announce support for MONO (a headset mic for example), or
469      * The total number of output channels. SO, if the device itself doesn't explicitly
470      * support STEREO, append to the channel config strings we are generating.
471      */
472     bool stereo_present = false;
473     unsigned index;
474     unsigned channel_count;
475 
476     for (index = 0; (channel_count = profile->channel_counts[index]) != 0; index++) {
477         stereo_present = stereo_present || channel_count == 2;
478         if (channel_count < names_size && names_array[channel_count] != NULL) {
479             if (num_entries++ != 0) {
480                 strncat(buffer, "|", buffer_size);
481             }
482             strncat(buffer, names_array[channel_count], buffer_size);
483         }
484     }
485 
486     /* emulated modes:
487      * always expose stereo as we can emulate it for PCM_OUT
488      */
489     if (!stereo_present) {
490         if (num_entries++ != 0) {
491             strncat(buffer, "|", buffer_size);
492         }
493         strncat(buffer, names_array[2], buffer_size); /* stereo */
494     }
495 
496     return strdup(buffer);
497 }
498