int main(int argc, char **argv)
{
int i, j, k, toread;
FILE *fp_ev;
int fp;
char *data;
size_t read_size;
struct iio_event_data dat;
char *BaseDirectoryName,
*TriggerDirectoryName,
*RingBufferDirectoryName;
BaseDirectoryName = find_type_by_name(device_name, "device");
if (BaseDirectoryName == NULL) {
printf("Failed to find the %s \n", device_name);
return -1;
}
TriggerDirectoryName = find_type_by_name(trigger_name, "trigger");
if (TriggerDirectoryName == NULL) {
printf("Failed to find the %s\n", trigger_name);
return -1;
}
RingBufferDirectoryName = find_ring_subelement(BaseDirectoryName,
"ring_buffer");
if (RingBufferDirectoryName == NULL) {
printf("Failed to find ring buffer\n");
return -1;
}
if (write_sysfs_string_and_verify("trigger/current_trigger",
BaseDirectoryName,
(char *)trigger_name) < 0) {
printf("Failed to write current_trigger file \n");
return -1;
}
/* Setup ring buffer parameters */
if (write_sysfs_int("length", RingBufferDirectoryName,
RingLength) < 0) {
printf("Failed to open the ring buffer length file \n");
return -1;
}
/* Enable the ring buffer */
if (write_sysfs_int("ring_enable", RingBufferDirectoryName, 1) < 0) {
printf("Failed to open the ring buffer control file \n");
return -1;
};
data = malloc(size_from_scanmode(NumVals, scan_ts)*RingLength);
if (!data) {
printf("Could not allocate space for usespace data store\n");
return -1;
}
/* Attempt to open non blocking the access dev */
fp = open(ring_access, O_RDONLY | O_NONBLOCK);
if (fp == -1) { /*If it isn't there make the node */
printf("Failed to open %s\n", ring_access);
return -1;
}
/* Attempt to open the event access dev (blocking this time) */
fp_ev = fopen(ring_event, "rb");
if (fp_ev == NULL) {
printf("Failed to open %s\n", ring_event);
return -1;
}
/* Wait for events 10 times */
for (j = 0; j < 10; j++) {
read_size = fread(&dat, 1, sizeof(struct iio_event_data),
fp_ev);
switch (dat.id) {
case IIO_EVENT_CODE_RING_100_FULL:
toread = RingLength;
break;
case IIO_EVENT_CODE_RING_75_FULL:
toread = RingLength*3/4;
break;
case IIO_EVENT_CODE_RING_50_FULL:
toread = RingLength/2;
break;
default:
printf("Unexpecteded event code\n");
continue;
}
read_size = read(fp,
data,
toread*size_from_scanmode(NumVals, scan_ts));
if (read_size == -EAGAIN) {
printf("nothing available \n");
continue;
}
for (i = 0;
i < read_size/size_from_scanmode(NumVals, scan_ts);
i++) {
for (k = 0; k < NumVals; k++) {
__s16 val = *(__s16 *)(&data[i*size_from_scanmode(NumVals, scan_ts)
+ (k)*2]);
printf("%05d ", val);
}
printf(" %lld\n",
*(__s64 *)(&data[(i+1)*size_from_scanmode(NumVals, scan_ts)
- sizeof(__s64)]));
}
}
/* Stop the ring buffer */
if (write_sysfs_int("ring_enable", RingBufferDirectoryName, 0) < 0) {
printf("Failed to open the ring buffer control file \n");
return -1;
};
/* Disconnect from the trigger - writing something that doesn't exist.*/
write_sysfs_string_and_verify("trigger/current_trigger",
BaseDirectoryName, "NULL");
free(BaseDirectoryName);
free(TriggerDirectoryName);
free(RingBufferDirectoryName);
free(data);
return 0;
}
int main(int argc, char **argv)
{
int ret;
int i, j, k, toread;
FILE *fp_ev;
int fp;
char *trigger_name, *dev_dir_name, *buf_dir_name;
char *data;
size_t read_size;
struct iio_event_data dat;
int dev_num, trig_num;
char *buffer_access, *buffer_event;
const char *iio_dir = "/sys/bus/iio/devices/";
int scan_size;
float gain = 1;
/* Find out which iio device is the accelerometer. */
dev_num = find_type_by_name(device_name, "device");
if (dev_num < 0) {
printf("Failed to find the %s\n", device_name);
ret = -ENODEV;
goto error_ret;
}
printf("iio device number being used is %d\n", dev_num);
asprintf(&dev_dir_name, "%sdevice%d", iio_dir, dev_num);
/*
* Build the trigger name.
* In this case we want the lis3l02dq's data ready trigger
* for this lis3l02dq. The naming is lis3l02dq_dev[n], where
* n matches the device number found above.
*/
ret = asprintf(&trigger_name, "%s%d", trigger_name_base, dev_num);
if (ret < 0) {
ret = -ENOMEM;
goto error_free_dev_dir_name;
}
/*
* Find the trigger by name.
* This is techically unecessary here as we only need to
* refer to the trigger by name and that name is already
* known.
*/
trig_num = find_type_by_name(trigger_name, "trigger");
if (trig_num < 0) {
printf("Failed to find the %s\n", trigger_name);
ret = -ENODEV;
goto error_free_triggername;
}
printf("iio trigger number being used is %d\n", trig_num);
/*
* Read in the scale value - in a more generic case, first
* check for accel_scale, then the indivual channel scales
*/
ret = read_sysfs_float("accel_scale", dev_dir_name, &gain);
if (ret)
goto error_free_triggername;;
/*
* Construct the directory name for the associated buffer.
* As we know that the lis3l02dq has only one buffer this may
* be built rather than found.
*/
ret = asprintf(&buf_dir_name, "%sdevice%d:buffer0", iio_dir, dev_num);
if (ret < 0) {
ret = -ENOMEM;
goto error_free_triggername;
}
/* Set the device trigger to be the data rdy trigger found above */
ret = write_sysfs_string_and_verify("trigger/current_trigger",
dev_dir_name,
trigger_name);
if (ret < 0) {
printf("Failed to write current_trigger file\n");
goto error_free_buf_dir_name;
}
/* Setup ring buffer parameters */
ret = write_sysfs_int("length", buf_dir_name, buf_len);
if (ret < 0)
goto error_free_buf_dir_name;
/* Enable the buffer */
ret = write_sysfs_int("ring_enable", buf_dir_name, 1);
if (ret < 0)
goto error_free_buf_dir_name;
data = malloc(size_from_scanmode(num_vals, scan_ts)*buf_len);
if (!data) {
ret = -ENOMEM;
goto error_free_buf_dir_name;
}
ret = asprintf(&buffer_access,
"/dev/device%d:buffer0:access0",
dev_num);
if (ret < 0) {
ret = -ENOMEM;
goto error_free_data;
}
ret = asprintf(&buffer_event, "/dev/device%d:buffer0:event0", dev_num);
if (ret < 0) {
ret = -ENOMEM;
goto error_free_data;
}
/* Attempt to open non blocking the access dev */
fp = open(buffer_access, O_RDONLY | O_NONBLOCK);
if (fp == -1) { /*If it isn't there make the node */
printf("Failed to open %s\n", buffer_access);
ret = -errno;
goto error_free_buffer_event;
}
/* Attempt to open the event access dev (blocking this time) */
fp_ev = fopen(buffer_event, "rb");
if (fp_ev == NULL) {
printf("Failed to open %s\n", buffer_event);
ret = -errno;
goto error_close_buffer_access;
}
/* Wait for events 10 times */
for (j = 0; j < num_loops; j++) {
read_size = fread(&dat, 1, sizeof(struct iio_event_data),
fp_ev);
switch (dat.id) {
case IIO_EVENT_CODE_RING_100_FULL:
toread = buf_len;
break;
case IIO_EVENT_CODE_RING_75_FULL:
toread = buf_len*3/4;
break;
case IIO_EVENT_CODE_RING_50_FULL:
toread = buf_len/2;
break;
default:
printf("Unexpecteded event code\n");
continue;
}
read_size = read(fp,
data,
toread*size_from_scanmode(num_vals, scan_ts));
if (read_size == -EAGAIN) {
printf("nothing available\n");
continue;
}
scan_size = size_from_scanmode(num_vals, scan_ts);
for (i = 0; i < read_size/scan_size; i++) {
for (k = 0; k < num_vals; k++) {
__s16 val = *(__s16 *)(&data[i*scan_size
+ (k)*2]);
printf("%05f ", (float)val*gain);
}
printf(" %lld\n",
*(__s64 *)(&data[(i + 1)
*size_from_scanmode(num_vals,
scan_ts)
- sizeof(__s64)]));
}
}
/* Stop the ring buffer */
ret = write_sysfs_int("ring_enable", buf_dir_name, 0);
if (ret < 0)
goto error_close_buffer_event;
/* Disconnect from the trigger - just write a dummy name.*/
write_sysfs_string("trigger/current_trigger",
dev_dir_name, "NULL");
error_close_buffer_event:
fclose(fp_ev);
error_close_buffer_access:
close(fp);
error_free_data:
free(data);
error_free_buffer_access:
free(buffer_access);
error_free_buffer_event:
free(buffer_event);
error_free_buf_dir_name:
free(buf_dir_name);
error_free_triggername:
free(trigger_name);
error_free_dev_dir_name:
free(dev_dir_name);
error_ret:
return ret;
}
