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9cd9f6b7 AG |
1 | /* |
2 | * This file is part of the libsigrok project. | |
3 | * | |
4 | * Copyright (C) 2011 Daniel Ribeiro <drwyrm@gmail.com> | |
5 | * Copyright (C) 2012 Uwe Hermann <uwe@hermann-uwe.de> | |
6 | * Copyright (C) 2012 Alexandru Gagniuc <mr.nuke.me@gmail.com> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License as published by | |
10 | * the Free Software Foundation; either version 2 of the License, or | |
11 | * (at your option) any later version. | |
12 | * | |
13 | * This program is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | * GNU General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU General Public License | |
19 | * along with this program; if not, write to the Free Software | |
20 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
21 | */ | |
22 | ||
23 | #include "protocol.h" | |
24 | #include "libsigrok.h" | |
25 | #include "libsigrok-internal.h" | |
26 | ||
65faa197 AG |
27 | /* |
28 | * There is no way to get a list of supported samplerates from ALSA. We could | |
29 | * use the 'plughw' interface of ALSA, in which case any format and/or | |
30 | * samplerate conversion would be performed by ALSA. However, we are interested | |
31 | * in the hardware capabilities, and have the infrastructure in sigrok to do so. | |
32 | * We therefore use the 'hw' interface. The downside is that the code gets a | |
33 | * little bulkier, as we have to keep track of the hardware capabilities, and | |
34 | * only use those that the hardware supports. Case in point, ALSA will not give | |
35 | * us a list of capabilities; we have to test for each one individually. Hence, | |
36 | * we keep lists of the capabilities we are interested in. | |
37 | */ | |
38 | static const unsigned int rates[] = { | |
39 | 5512, | |
40 | 8000, | |
41 | 11025, | |
42 | 16000, | |
43 | 22050, | |
44 | 32000, | |
45 | 44100, | |
46 | 48000, | |
47 | 64000, | |
48 | 88200, | |
49 | 96000, | |
50 | 176400, | |
51 | 192000, | |
52 | 384000, /* Yes, there are sound cards that go this high */ | |
53 | }; | |
54 | ||
6944b2d0 AG |
55 | static void alsa_scan_handle_dev(GSList **devices, |
56 | const char *cardname, const char *alsaname, | |
57 | struct sr_dev_driver *di, | |
58 | snd_pcm_info_t *pcminfo) | |
59 | { | |
60 | struct drv_context *drvc = NULL; | |
61 | struct sr_dev_inst *sdi = NULL; | |
62 | struct dev_context *devc = NULL; | |
63 | struct sr_probe *probe; | |
64 | int ret; | |
65faa197 AG |
65 | unsigned int i, offset, channels, minrate, maxrate, rate; |
66 | uint64_t hwrates[ARRAY_SIZE(rates)]; | |
67 | uint64_t *devrates = NULL; | |
6944b2d0 AG |
68 | snd_pcm_t *temp_handle = NULL; |
69 | snd_pcm_hw_params_t *hw_params = NULL; | |
70 | ||
71 | drvc = di->priv; | |
72 | ||
73 | /* | |
65faa197 AG |
74 | * Get hardware parameters: |
75 | * The number of channels, for example, are our sigrok probes. Getting | |
76 | * this information needs a detour. We need to open the device, then | |
77 | * query it and/or test different parameters. A side-effect of is that | |
78 | * we create a snd_pcm_hw_params_t object. We take advantage of the | |
6944b2d0 AG |
79 | * situation, and pass this object in our dev_context->hw_params, |
80 | * eliminating the need to free() it and malloc() it later. | |
81 | */ | |
82 | ret = snd_pcm_open(&temp_handle, alsaname, SND_PCM_STREAM_CAPTURE, 0); | |
83 | if (ret < 0) { | |
84 | sr_err("Cannot open device: %s.", snd_strerror(ret)); | |
85 | goto scan_error_cleanup; | |
86 | } | |
87 | ||
88 | ret = snd_pcm_hw_params_malloc(&hw_params); | |
89 | if (ret < 0) { | |
90 | sr_err("Error allocating hardware parameter structure: %s.", | |
91 | snd_strerror(ret)); | |
92 | goto scan_error_cleanup; | |
93 | } | |
94 | ||
95 | ret = snd_pcm_hw_params_any(temp_handle, hw_params); | |
96 | if (ret < 0) { | |
97 | sr_err("Error initializing hardware parameter structure: %s.", | |
98 | snd_strerror(ret)); | |
99 | goto scan_error_cleanup; | |
100 | } | |
101 | ||
102 | snd_pcm_hw_params_get_channels_max(hw_params, &channels); | |
103 | ||
65faa197 AG |
104 | /* |
105 | * We need to test if each samplerate between min and max is supported. | |
106 | * Unfortunately, ALSA won't just throw a list at us. | |
107 | */ | |
108 | snd_pcm_hw_params_get_rate_min(hw_params, &minrate, 0); | |
109 | snd_pcm_hw_params_get_rate_max(hw_params, &maxrate, 0); | |
110 | for (i = 0, offset = 0; i < ARRAY_SIZE(rates); i++) | |
111 | { | |
112 | rate = rates[i]; | |
113 | if (rate < minrate) | |
114 | continue; | |
115 | if (rate > maxrate) | |
116 | break; | |
117 | ret = snd_pcm_hw_params_test_rate(temp_handle, hw_params, | |
118 | rate, 0); | |
119 | if (ret >= 0) | |
120 | hwrates[offset++] = rate; | |
121 | } | |
122 | hwrates[offset++] = 0; | |
123 | ||
6944b2d0 AG |
124 | snd_pcm_close(temp_handle); |
125 | temp_handle = NULL; | |
126 | ||
127 | /* | |
65faa197 AG |
128 | * Now we are done querying the hardware parameters. |
129 | * If we made it here, we know everything we want to know, and it's time | |
130 | * to create our sigrok device. | |
6944b2d0 AG |
131 | */ |
132 | sr_info("Device %s has %d channels.", alsaname, channels); | |
133 | if (!(sdi = sr_dev_inst_new(0, SR_ST_INACTIVE, "ALSA:", | |
134 | cardname, snd_pcm_info_get_name(pcminfo)))) { | |
135 | sr_err("Device instance malloc failed."); | |
136 | goto scan_error_cleanup; | |
137 | } | |
138 | if (!(devc = g_try_malloc0(sizeof(struct dev_context)))) { | |
139 | sr_err("Device context malloc failed."); | |
140 | goto scan_error_cleanup; | |
141 | } | |
65faa197 AG |
142 | if (!(devrates = g_try_malloc(offset * sizeof(uint64_t)))) { |
143 | sr_err("Samplerate list malloc failed."); | |
144 | goto scan_error_cleanup; | |
145 | } | |
6944b2d0 AG |
146 | |
147 | devc->hwdev = g_strdup(alsaname); | |
148 | devc->num_probes = channels; | |
149 | devc->hw_params = hw_params; | |
65faa197 AG |
150 | memcpy(devrates, hwrates, offset * sizeof(uint64_t)); |
151 | devc->supp_rates.list = devrates; | |
152 | ||
6944b2d0 AG |
153 | sdi->priv = devc; |
154 | sdi->driver = di; | |
155 | ||
156 | for (i = 0; i < devc->num_probes; i++) { | |
157 | char p_name[32]; | |
158 | snprintf(p_name, sizeof(p_name), "Ch_%d", i); | |
159 | if (!(probe = sr_probe_new(0, SR_PROBE_ANALOG, TRUE, p_name))) | |
160 | goto scan_error_cleanup; | |
161 | sdi->probes = g_slist_append(sdi->probes, probe); | |
162 | } | |
163 | ||
164 | drvc->instances = g_slist_append(drvc->instances, sdi); | |
165 | *devices = g_slist_append(*devices, sdi); | |
166 | return; | |
167 | ||
168 | scan_error_cleanup: | |
169 | if (devc) { | |
170 | if (devc->hwdev) | |
171 | g_free((void*)devc->hwdev); | |
172 | g_free(devc); | |
173 | } | |
65faa197 AG |
174 | if (devrates) |
175 | g_free(devrates); | |
6944b2d0 AG |
176 | if (sdi) |
177 | sr_dev_inst_free(sdi); | |
178 | if (hw_params) | |
179 | snd_pcm_hw_params_free(hw_params); | |
180 | if (temp_handle) | |
181 | snd_pcm_close(temp_handle); | |
182 | return; | |
183 | } | |
184 | ||
185 | /** | |
186 | * \brief Scan all alsa devices, and translate them to sigrok devices | |
187 | * | |
188 | * Each alsa device (not alsa card) gets its own sigrok device | |
189 | * For example, | |
190 | * hw:1,0 == sigrok device 0 | |
191 | * hw:1,1 == sigrok device 1 | |
192 | * hw:2,0 == sigrok device 2 | |
193 | * hw:2,1 == sigrok device 3 | |
194 | * hw:2,2 == sigrok device 4 | |
195 | * [...] | |
196 | * \n | |
197 | * We don't currently look at alsa subdevices. We only use subdevice 0. | |
198 | * Every input device will have a its own channels (Left, Right, etc). Each of | |
199 | * those channels gets mapped to a different sigrok probe. A device with 4 | |
200 | * channels will have 4 probes from sigrok's perspective. | |
201 | */ | |
202 | SR_PRIV GSList *alsa_scan(GSList *options, struct sr_dev_driver *di) | |
203 | { | |
204 | GSList *devices = NULL; | |
205 | snd_ctl_t *handle; | |
206 | int card, ret, dev; | |
207 | snd_ctl_card_info_t *info; | |
208 | snd_pcm_info_t *pcminfo; | |
209 | const char* cardname; | |
210 | /* TODO */ | |
211 | (void)options; | |
212 | ||
213 | if (snd_ctl_card_info_malloc(&info) < 0) { | |
214 | sr_err("Cannot malloc card info."); | |
215 | return NULL; | |
216 | } | |
217 | if (snd_pcm_info_malloc(&pcminfo) < 0) { | |
218 | sr_err("Cannot malloc pcm info."); | |
219 | return NULL; | |
220 | } | |
221 | ||
222 | card = -1; | |
223 | while (snd_card_next(&card) >= 0 && card >= 0) { | |
224 | char hwcard[32]; | |
225 | snprintf(hwcard, sizeof(hwcard), "hw:%d", card); | |
226 | if ((ret = snd_ctl_open(&handle, hwcard, 0)) < 0) { | |
227 | sr_err("Cannot open (%i): %s", card, snd_strerror(ret)); | |
228 | continue; | |
229 | } | |
230 | if ((ret = snd_ctl_card_info(handle, info)) < 0) { | |
231 | sr_err("Cannot get hardware info (%i): %s", | |
232 | card, snd_strerror(ret)); | |
233 | snd_ctl_close(handle); | |
234 | continue; | |
235 | } | |
236 | dev = -1; | |
237 | while (snd_ctl_pcm_next_device(handle, &dev) >= 0 && dev >= 0) { | |
238 | char hwdev[32]; | |
239 | snprintf(hwdev, sizeof(hwdev), "%s,%d", hwcard, dev); | |
240 | /* | |
241 | * TODO: We always use subdevice 0, but we have yet to | |
242 | * explore the possibilities opened up by other | |
243 | * subdevices. Most hardware only has subdevice 0. | |
244 | */ | |
245 | snd_pcm_info_set_device(pcminfo, dev); | |
246 | snd_pcm_info_set_subdevice(pcminfo, 0); | |
247 | snd_pcm_info_set_stream(pcminfo, | |
248 | SND_PCM_STREAM_CAPTURE); | |
249 | if ((ret = snd_ctl_pcm_info(handle, pcminfo)) < 0) { | |
250 | sr_err("Cannot get device info: %s", | |
251 | snd_strerror(ret)); | |
252 | continue; | |
253 | } | |
254 | ||
255 | cardname = snd_ctl_card_info_get_name(info); | |
256 | sr_info("card %i: %s [%s], device %i: %s [%s]", | |
257 | card, snd_ctl_card_info_get_id(info), cardname, | |
258 | dev, snd_pcm_info_get_id(pcminfo), | |
259 | snd_pcm_info_get_name(pcminfo)); | |
260 | ||
261 | alsa_scan_handle_dev(&devices, cardname, hwdev, | |
262 | di, pcminfo); | |
263 | } | |
264 | snd_ctl_close(handle); | |
265 | } | |
266 | ||
267 | snd_pcm_info_free(pcminfo); | |
268 | snd_ctl_card_info_free(info); | |
269 | ||
270 | return devices; | |
271 | } | |
272 | ||
273 | /* | |
274 | * Helper to be used with g_slist_free_full(); for properly freeing an alsa | |
275 | * dev instance. | |
276 | */ | |
277 | SR_PRIV void alsa_dev_inst_clear(struct sr_dev_inst *sdi) | |
278 | { | |
279 | struct dev_context *devc; | |
280 | ||
281 | if (!(devc = sdi->priv)) | |
282 | return; | |
283 | ||
284 | snd_pcm_hw_params_free(devc->hw_params); | |
65faa197 | 285 | g_free((void*)devc->supp_rates.list); |
6944b2d0 AG |
286 | sr_dev_inst_free(sdi); |
287 | } | |
288 | ||
65faa197 AG |
289 | /* |
290 | * Sets the samplerate of the ALSA device | |
291 | * | |
292 | * Changes the samplerate of the given ALSA device if the specified samplerate | |
293 | * is supported by the hardware. | |
294 | * The new samplerate is recorded, but it is not applied to the hardware. The | |
295 | * samplerate is applied to the hardware only when acquisition is started via | |
296 | * dev_acquisition_start(), and cannot be changed during acquisition. To change | |
297 | * the samplerate, several steps are needed: | |
298 | * 1) If acquisition is running, it must first be stopped. | |
299 | * 2) dev_config_set() must be called with the new samplerate. | |
300 | * 3) When starting a new acquisition, the new samplerate is applied. | |
301 | */ | |
302 | SR_PRIV int alsa_set_samplerate(const struct sr_dev_inst *sdi, | |
303 | const uint64_t newrate) | |
304 | { | |
305 | struct dev_context *devc; | |
306 | size_t i; | |
307 | uint64_t rate = 0; | |
308 | ||
309 | if (!(devc = sdi->priv)) | |
310 | return SR_ERR_ARG; | |
311 | ||
312 | i = 0; | |
313 | do { | |
314 | if (newrate == devc->supp_rates.list[i]) { | |
315 | rate = newrate; | |
316 | break; | |
317 | } | |
318 | } while (devc->supp_rates.list[i++] != 0); | |
319 | ||
320 | if (!rate) { | |
321 | sr_err("Sample rate " PRIu64 " not supported.", newrate); | |
322 | return SR_ERR_ARG; | |
323 | } | |
324 | ||
325 | devc->cur_samplerate = rate; | |
326 | return SR_OK; | |
327 | } | |
328 | ||
9cd9f6b7 AG |
329 | SR_PRIV int alsa_receive_data(int fd, int revents, void *cb_data) |
330 | { | |
331 | struct sr_dev_inst *sdi; | |
332 | struct dev_context *devc; | |
333 | struct sr_datafeed_packet packet; | |
334 | struct sr_datafeed_analog analog; | |
729850c9 | 335 | int16_t inbuf[4096]; |
9cd9f6b7 | 336 | int i, x, count, offset, samples_to_get; |
729850c9 AG |
337 | int16_t tmp16; |
338 | const float s16norm = 1 / (float)(1<<15); | |
9cd9f6b7 AG |
339 | |
340 | (void)fd; | |
341 | (void)revents; | |
342 | ||
343 | sdi = cb_data; | |
344 | devc = sdi->priv; | |
345 | ||
346 | memset(&analog, 0, sizeof(struct sr_datafeed_analog)); | |
347 | memset(inbuf, 0, sizeof(inbuf)); | |
348 | ||
349 | samples_to_get = MIN(4096 / 4, devc->limit_samples); | |
350 | ||
351 | sr_spew("Getting %d samples from audio device.", samples_to_get); | |
352 | count = snd_pcm_readi(devc->capture_handle, inbuf, samples_to_get); | |
353 | ||
354 | if (count < 0) { | |
355 | sr_err("Failed to read samples: %s.", snd_strerror(count)); | |
356 | return FALSE; | |
357 | } else if (count != samples_to_get) { | |
358 | sr_spew("Only got %d/%d samples.", count, samples_to_get); | |
359 | } | |
360 | ||
361 | analog.data = g_try_malloc0(count * sizeof(float) * devc->num_probes); | |
362 | if (!analog.data) { | |
363 | sr_err("Failed to malloc sample buffer."); | |
364 | return FALSE; | |
365 | } | |
366 | ||
367 | offset = 0; | |
729850c9 AG |
368 | /* |
369 | * It's impossible to know what voltage levels the soundcard handles. | |
370 | * Some handle 0 dBV rms, some 0dBV peak-to-peak, +4dbmW (600 ohm), etc | |
371 | * Each of these corresponds to a different voltage, and there is no | |
372 | * mechanism to determine this voltage. The best solution is to send all | |
373 | * audio data as a normalized float, and let the frontend or user worry | |
374 | * about the calibration. | |
375 | */ | |
376 | for (i = 0; i < count; i += devc->num_probes) { | |
9cd9f6b7 | 377 | for (x = 0; x < devc->num_probes; x++) { |
729850c9 AG |
378 | tmp16 = inbuf[i+x]; |
379 | analog.data[offset++] = tmp16 * s16norm; | |
9cd9f6b7 AG |
380 | } |
381 | } | |
382 | ||
383 | /* Send a sample packet with the analog values. */ | |
384 | analog.num_samples = count; | |
385 | analog.mq = SR_MQ_VOLTAGE; /* FIXME */ | |
386 | analog.unit = SR_UNIT_VOLT; /* FIXME */ | |
387 | packet.type = SR_DF_ANALOG; | |
388 | packet.payload = &analog; | |
389 | sr_session_send(devc->cb_data, &packet); | |
390 | ||
391 | g_free(analog.data); | |
392 | ||
393 | devc->num_samples += count; | |
394 | ||
395 | /* Stop acquisition if we acquired enough samples. */ | |
35e199da UH |
396 | if (devc->limit_samples && devc->num_samples >= devc->limit_samples) { |
397 | sr_info("Requested number of samples reached."); | |
398 | sdi->driver->dev_acquisition_stop(sdi, cb_data); | |
9cd9f6b7 AG |
399 | } |
400 | ||
401 | return TRUE; | |
402 | } | |
6944b2d0 | 403 |