int iioc_sampling_setup(struct iio_device *adc_dev,
struct iio_device *trigger_dev,
unsigned int sampling_freq,
unsigned int sample_count
)
{
unsigned int i;
int ret;
unsigned int min_timeout = 2000;
if (!adc_dev || !trigger_dev)
return -ENODEV;
unsigned int nb_channels = iio_device_get_channels_count(adc_dev);
if (nb_channels == 0) {
IIOC_DBG("There is 0 Channel in adc_device.\n");
return -EIO;
}
unsigned int sample_size = iio_device_get_sample_size(adc_dev);
if (sample_size == 0) {
IIOC_DBG("Sample Size is 0.\n");
return -ENODATA;
}
struct extra_dev_info *dev_info = iio_device_get_data(adc_dev);
if (dev_info->input_device == false) {
IIOC_DBG("adc_dev is not an input device.\n");
return -EIO;
}
//°ó¶¨trigger
ret = iio_device_set_trigger(adc_dev, trigger_dev);
if (ret)
{
#ifdef _DEBUG
const char *trigger_name = iio_device_get_name(trigger_dev);
const char *adc_name = iio_device_get_name(adc_dev);
IIOC_DBG("Can not bind the %s with %s.\n", trigger_name, adc_name);
#endif
return -EIO;
}
//ɾ³ý¾Ébuffer
if (dev_info->buffer)
iio_buffer_destroy(dev_info->buffer);
dev_info->buffer = NULL;
//ÉèÖÃsample_count(buffer´óС)
dev_info->sample_count = sample_count;
//ʹÄÜͨµÀ£¬²¢ÎªÃ¿¸öͨµÀ·ÖÅäÄÚ´æ¿Õ¼ä
for (i = 0; i < nb_channels; i++) {
struct iio_channel *ch = iio_device_get_channel(adc_dev, i);
struct extra_chn_info *chn_info = iio_channel_get_data(ch);
if (chn_info->enabled)
iio_channel_enable(ch);
else
iio_channel_disable(ch);
if (chn_info->data_ref)
free(chn_info->data_ref);
chn_info->data_ref = (int16_t *)calloc(dev_info->sample_count, sizeof(int16_t));
if (!chn_info->data_ref) {
IIOC_DBG("Can not calloc channel data mem.\n");
goto error_calloc_chn_data_ref;
}
}
dev_info->sampling_freq = sampling_freq;
//ÖØаó¶¨Êý¾Ý
iio_device_set_data(adc_dev, dev_info);
//ÉèÖó¬Ê±
if (sampling_freq > 0) {
/* 2 x capture time + 2s */
unsigned int timeout = dev_info->sample_count * 1000 / sampling_freq;
timeout += 2000;
if (timeout > min_timeout)
min_timeout = timeout;
}
if (dev_info->ctx_info->ctx)
iio_context_set_timeout(dev_info->ctx_info->ctx, min_timeout);
return 0;
error_calloc_chn_data_ref:
for (i = 0; i < nb_channels; i++) {
struct iio_channel *ch = iio_device_get_channel(adc_dev, i);
struct extra_chn_info *chn_info = iio_channel_get_data(ch);
if (chn_info->data_ref)
free(chn_info->data_ref);
}
return -ENOMEM;
}
int main(int argc, char **argv)
{
unsigned int i, nb_channels;
unsigned int buffer_size = SAMPLES_PER_READ;
const char *arg_uri = NULL;
const char *arg_ip = NULL;
int c, option_index = 0;
struct iio_device *dev;
size_t sample_size;
int timeout = -1;
bool scan_for_context = false;
while ((c = getopt_long(argc, argv, "+hn:u:t:b:s:T:a",
options, &option_index)) != -1) {
switch (c) {
case 'h':
usage();
return EXIT_SUCCESS;
case 'n':
arg_ip = optarg;
break;
case 'u':
arg_uri = optarg;
break;
case 'a':
scan_for_context = true;
break;
case 't':
trigger_name = optarg;
break;
case 'b':
buffer_size = atoi(optarg);
break;
case 's':
num_samples = atoi(optarg);
break;
case 'T':
timeout = atoi(optarg);
break;
case '?':
return EXIT_FAILURE;
}
}
if (argc == optind) {
fprintf(stderr, "Incorrect number of arguments.\n\n");
usage();
return EXIT_FAILURE;
}
setup_sig_handler();
if (scan_for_context)
ctx = scan();
else if (arg_uri)
ctx = iio_create_context_from_uri(arg_uri);
else if (arg_ip)
ctx = iio_create_network_context(arg_ip);
else
ctx = iio_create_default_context();
if (!ctx) {
fprintf(stderr, "Unable to create IIO context\n");
return EXIT_FAILURE;
}
if (timeout >= 0)
iio_context_set_timeout(ctx, timeout);
dev = iio_context_find_device(ctx, argv[optind]);
if (!dev) {
fprintf(stderr, "Device %s not found\n", argv[optind]);
iio_context_destroy(ctx);
return EXIT_FAILURE;
}
if (trigger_name) {
struct iio_device *trigger = iio_context_find_device(
ctx, trigger_name);
if (!trigger) {
fprintf(stderr, "Trigger %s not found\n", trigger_name);
iio_context_destroy(ctx);
return EXIT_FAILURE;
}
if (!iio_device_is_trigger(trigger)) {
fprintf(stderr, "Specified device is not a trigger\n");
iio_context_destroy(ctx);
return EXIT_FAILURE;
}
/*
* Fixed rate for now. Try new ABI first,
* fail gracefully to remain compatible.
*/
if (iio_device_attr_write_longlong(trigger,
"sampling_frequency", DEFAULT_FREQ_HZ) < 0)
iio_device_attr_write_longlong(trigger,
"frequency", DEFAULT_FREQ_HZ);
iio_device_set_trigger(dev, trigger);
}
nb_channels = iio_device_get_channels_count(dev);
if (argc == optind + 1) {
/* Enable all channels */
for (i = 0; i < nb_channels; i++)
iio_channel_enable(iio_device_get_channel(dev, i));
} else {
for (i = 0; i < nb_channels; i++) {
unsigned int j;
struct iio_channel *ch = iio_device_get_channel(dev, i);
for (j = optind + 1; j < (unsigned int) argc; j++) {
const char *n = iio_channel_get_name(ch);
if (!strcmp(argv[j], iio_channel_get_id(ch)) ||
(n && !strcmp(n, argv[j])))
iio_channel_enable(ch);
}
}
}
sample_size = iio_device_get_sample_size(dev);
buffer = iio_device_create_buffer(dev, buffer_size, false);
if (!buffer) {
char buf[256];
iio_strerror(errno, buf, sizeof(buf));
fprintf(stderr, "Unable to allocate buffer: %s\n", buf);
iio_context_destroy(ctx);
return EXIT_FAILURE;
}
while (app_running) {
int ret = iio_buffer_refill(buffer);
if (ret < 0) {
if (app_running) {
char buf[256];
iio_strerror(-ret, buf, sizeof(buf));
fprintf(stderr, "Unable to refill buffer: %s\n", buf);
}
break;
}
/* If there are only the samples we requested, we don't need to
* demux */
if (iio_buffer_step(buffer) == sample_size) {
void *start = iio_buffer_start(buffer);
size_t read_len, len = (intptr_t) iio_buffer_end(buffer)
- (intptr_t) start;
if (num_samples && len > num_samples * sample_size)
len = num_samples * sample_size;
for (read_len = len; len; ) {
size_t nb = fwrite(start, 1, len, stdout);
if (!nb)
goto err_destroy_buffer;
len -= nb;
start = (void *)((intptr_t) start + nb);
}
if (num_samples) {
num_samples -= read_len / sample_size;
if (!num_samples)
quit_all(EXIT_SUCCESS);
}
} else {
iio_buffer_foreach_sample(buffer, print_sample, NULL);
}
}
err_destroy_buffer:
iio_buffer_destroy(buffer);
iio_context_destroy(ctx);
return exit_code;
}
