SR_PRIV unsigned int fx2lafw_get_timeout(struct dev_context *devc)
{
size_t total_size;
unsigned int timeout;
total_size = fx2lafw_get_buffer_size(devc) *
fx2lafw_get_number_of_transfers(devc);
timeout = total_size / to_bytes_per_ms(devc->cur_samplerate);
return timeout + timeout / 4; /* Leave a headroom of 25% percent. */
}
static int dev_acquisition_start(const struct sr_dev_inst *sdi, void *cb_data)
{
struct dev_context *devc;
struct drv_context *drvc;
struct sr_usb_dev_inst *usb;
struct sr_trigger *trigger;
struct libusb_transfer *transfer;
unsigned int i, timeout, num_transfers;
int ret;
unsigned char *buf;
size_t size;
if (sdi->status != SR_ST_ACTIVE)
return SR_ERR_DEV_CLOSED;
drvc = di->priv;
devc = sdi->priv;
usb = sdi->conn;
devc->cb_data = cb_data;
devc->sent_samples = 0;
devc->acq_aborted = FALSE;
devc->empty_transfer_count = 0;
if ((trigger = sr_session_trigger_get())) {
devc->stl = soft_trigger_logic_new(sdi, trigger);
devc->trigger_fired = FALSE;
} else
devc->trigger_fired = TRUE;
timeout = fx2lafw_get_timeout(devc);
num_transfers = fx2lafw_get_number_of_transfers(devc);
size = fx2lafw_get_buffer_size(devc);
devc->submitted_transfers = 0;
devc->transfers = g_try_malloc0(sizeof(*devc->transfers) * num_transfers);
if (!devc->transfers) {
sr_err("USB transfers malloc failed.");
return SR_ERR_MALLOC;
}
devc->num_transfers = num_transfers;
for (i = 0; i < num_transfers; i++) {
if (!(buf = g_try_malloc(size))) {
sr_err("USB transfer buffer malloc failed.");
return SR_ERR_MALLOC;
}
transfer = libusb_alloc_transfer(0);
libusb_fill_bulk_transfer(transfer, usb->devhdl,
2 | LIBUSB_ENDPOINT_IN, buf, size,
fx2lafw_receive_transfer, (void *)sdi, timeout);
if ((ret = libusb_submit_transfer(transfer)) != 0) {
sr_err("Failed to submit transfer: %s.",
libusb_error_name(ret));
libusb_free_transfer(transfer);
g_free(buf);
fx2lafw_abort_acquisition(devc);
return SR_ERR;
}
devc->transfers[i] = transfer;
devc->submitted_transfers++;
}
devc->ctx = drvc->sr_ctx;
usb_source_add(devc->ctx, timeout, receive_data, NULL);
/* Send header packet to the session bus. */
std_session_send_df_header(cb_data, LOG_PREFIX);
if ((ret = fx2lafw_command_start_acquisition(sdi)) != SR_OK) {
fx2lafw_abort_acquisition(devc);
return ret;
}
return SR_OK;
}