2 * This file is part of the sigrok project.
4 * Copyright (C) 2011 Daniel Ribeiro <drwyrm@gmail.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 #include "config.h" /* Must come before sigrok.h */
25 #include <alsa/asoundlib.h>
27 #include "sigrok-internal.h"
30 #define SAMPLE_WIDTH 16
31 #define AUDIO_DEV "plughw:0,0"
33 static int capabilities[] = {
35 SR_HWCAP_LIMIT_SAMPLES,
39 static const char *probe_names[NUM_PROBES + 1] = {
45 static GSList *device_instances = NULL;
49 uint64_t limit_samples;
50 snd_pcm_t *capture_handle;
51 snd_pcm_hw_params_t *hw_params;
55 static int hw_init(const char *deviceinfo)
57 struct sr_device_instance *sdi;
60 /* Avoid compiler warnings. */
61 deviceinfo = deviceinfo;
63 if (!(alsa = g_try_malloc0(sizeof(struct alsa)))) {
64 sr_err("alsa: %s: alsa malloc failed", __func__);
68 sdi = sr_device_instance_new(0, SR_ST_ACTIVE, "alsa", NULL, NULL);
74 device_instances = g_slist_append(device_instances, sdi);
82 static int hw_opendev(int device_index)
84 struct sr_device_instance *sdi;
88 if (!(sdi = sr_get_device_instance(device_instances, device_index)))
92 err = snd_pcm_open(&alsa->capture_handle, AUDIO_DEV,
93 SND_PCM_STREAM_CAPTURE, 0);
95 sr_warn("cannot open audio device %s (%s)", AUDIO_DEV,
100 err = snd_pcm_hw_params_malloc(&alsa->hw_params);
102 sr_warn("cannot allocate hardware parameter structure (%s)",
107 err = snd_pcm_hw_params_any(alsa->capture_handle, alsa->hw_params);
109 sr_warn("cannot initialize hardware parameter structure (%s)",
117 static int hw_closedev(int device_index)
119 struct sr_device_instance *sdi;
122 if (!(sdi = sr_get_device_instance(device_instances, device_index))) {
123 sr_err("alsa: %s: sdi was NULL", __func__);
124 return SR_ERR; /* TODO: SR_ERR_ARG? */
127 if (!(alsa = sdi->priv)) {
128 sr_err("alsa: %s: sdi->priv was NULL", __func__);
129 return SR_ERR; /* TODO: SR_ERR_ARG? */
132 // TODO: Return values of snd_*?
134 snd_pcm_hw_params_free(alsa->hw_params);
135 if (alsa->capture_handle)
136 snd_pcm_close(alsa->capture_handle);
141 static void hw_cleanup(void)
143 struct sr_device_instance *sdi;
145 if (!(sdi = sr_get_device_instance(device_instances, 0)))
149 sr_device_instance_free(sdi);
152 static void *hw_get_device_info(int device_index, int device_info_id)
154 struct sr_device_instance *sdi;
158 if (!(sdi = sr_get_device_instance(device_instances, device_index)))
162 switch (device_info_id) {
166 case SR_DI_NUM_PROBES:
167 info = GINT_TO_POINTER(NUM_PROBES);
169 case SR_DI_PROBE_NAMES:
172 case SR_DI_CUR_SAMPLERATE:
173 info = &alsa->cur_rate;
175 // case SR_DI_PROBE_TYPE:
176 // info = GINT_TO_POINTER(SR_PROBE_TYPE_ANALOG);
183 static int hw_get_status(int device_index)
185 /* Avoid compiler warnings. */
186 device_index = device_index;
191 static int *hw_get_capabilities(void)
196 static int hw_set_configuration(int device_index, int capability, void *value)
198 struct sr_device_instance *sdi;
201 if (!(sdi = sr_get_device_instance(device_instances, device_index)))
205 switch (capability) {
206 case SR_HWCAP_PROBECONFIG:
208 case SR_HWCAP_SAMPLERATE:
209 alsa->cur_rate = *(uint64_t *) value;
211 case SR_HWCAP_LIMIT_SAMPLES:
212 alsa->limit_samples = *(uint64_t *) value;
219 static int receive_data(int fd, int revents, void *user_data)
221 struct sr_device_instance *sdi = user_data;
222 struct alsa *alsa = sdi->priv;
223 struct sr_datafeed_packet packet;
224 struct sr_analog_sample *sample;
225 unsigned int sample_size = sizeof(struct sr_analog_sample) +
226 (NUM_PROBES * sizeof(struct sr_analog_probe));
235 memset(inb, 0, sizeof(inb));
236 count = snd_pcm_readi(alsa->capture_handle, inb,
237 MIN(4096/4, alsa->limit_samples));
239 sr_warn("Failed to read samples");
243 if (!(outb = g_try_malloc(sample_size * count))) {
244 sr_err("alsa: %s: outb malloc failed", __func__);
248 for (i = 0; i < count; i++) {
249 sample = (struct sr_analog_sample *)
250 (outb + (i * sample_size));
251 sample->num_probes = NUM_PROBES;
253 for (x = 0; x < NUM_PROBES; x++) {
254 sample->probes[x].val =
255 *(uint16_t *) (inb + (i * 4) + (x * 2));
256 sample->probes[x].val &= ((1 << 16) - 1);
257 sample->probes[x].res = 16;
261 packet.type = SR_DF_ANALOG;
262 packet.length = count * sample_size;
263 packet.unitsize = sample_size;
264 packet.payload = outb;
265 sr_session_bus(user_data, &packet);
267 alsa->limit_samples -= count;
269 } while (alsa->limit_samples > 0);
271 packet.type = SR_DF_END;
272 sr_session_bus(user_data, &packet);
277 static int hw_start_acquisition(int device_index, gpointer session_device_id)
279 struct sr_device_instance *sdi;
281 struct sr_datafeed_packet packet;
282 struct sr_datafeed_header header;
287 if (!(sdi = sr_get_device_instance(device_instances, device_index)))
291 err = snd_pcm_hw_params_set_access(alsa->capture_handle,
292 alsa->hw_params, SND_PCM_ACCESS_RW_INTERLEAVED);
294 sr_warn("cannot set access type (%s)", snd_strerror(err));
298 /* FIXME: Hardcoded for 16bits */
299 err = snd_pcm_hw_params_set_format(alsa->capture_handle,
300 alsa->hw_params, SND_PCM_FORMAT_S16_LE);
302 sr_warn("cannot set sample format (%s)", snd_strerror(err));
306 err = snd_pcm_hw_params_set_rate_near(alsa->capture_handle,
307 alsa->hw_params, (unsigned int *) &alsa->cur_rate, 0);
309 sr_warn("cannot set sample rate (%s)", snd_strerror(err));
313 err = snd_pcm_hw_params_set_channels(alsa->capture_handle,
314 alsa->hw_params, NUM_PROBES);
316 sr_warn("cannot set channel count (%s)", snd_strerror(err));
320 err = snd_pcm_hw_params(alsa->capture_handle, alsa->hw_params);
322 sr_warn("cannot set parameters (%s)", snd_strerror(err));
326 err = snd_pcm_prepare(alsa->capture_handle);
328 sr_warn("cannot prepare audio interface for use (%s)",
333 count = snd_pcm_poll_descriptors_count(alsa->capture_handle);
335 sr_warn("Unable to obtain poll descriptors count");
339 if (!(ufds = g_try_malloc(count * sizeof(struct pollfd)))) {
340 sr_warn("alsa: %s: ufds malloc failed", __func__);
341 return SR_ERR_MALLOC;
344 err = snd_pcm_poll_descriptors(alsa->capture_handle, ufds, count);
346 sr_warn("Unable to obtain poll descriptors (%s)",
352 alsa->session_id = session_device_id;
353 sr_source_add(ufds[0].fd, ufds[0].events, 10, receive_data, sdi);
355 packet.type = SR_DF_HEADER;
356 packet.length = sizeof(struct sr_datafeed_header);
357 packet.payload = (unsigned char *) &header;
358 header.feed_version = 1;
359 gettimeofday(&header.starttime, NULL);
360 header.samplerate = alsa->cur_rate;
361 header.num_analog_probes = NUM_PROBES;
362 header.num_logic_probes = 0;
363 header.protocol_id = SR_PROTO_RAW;
364 sr_session_bus(session_device_id, &packet);
370 static void hw_stop_acquisition(int device_index, gpointer session_device_id)
372 /* Avoid compiler warnings. */
373 device_index = device_index;
374 session_device_id = session_device_id;
377 struct sr_device_plugin alsa_plugin_info = {
379 .longname = "ALSA driver",
382 .cleanup = hw_cleanup,
383 .opendev = hw_opendev,
384 .closedev = hw_closedev,
385 .get_device_info = hw_get_device_info,
386 .get_status = hw_get_status,
387 .get_capabilities = hw_get_capabilities,
388 .set_configuration = hw_set_configuration,
389 .start_acquisition = hw_start_acquisition,
390 .stop_acquisition = hw_stop_acquisition,