+/*
+ * Return one 16bit data entity of a DRAM cluster at the specified index.
+ */
+static uint16_t sigma_dram_cluster_data(struct sigma_dram_cluster *cl, int idx)
+{
+ uint16_t sample;
+
+ sample = 0;
+ sample |= cl->samples[idx].sample_lo << 0;
+ sample |= cl->samples[idx].sample_hi << 8;
+ sample = (sample >> 8) | (sample << 8);
+ return sample;
+}
+
+/*
+ * Deinterlace sample data that was retrieved at 100MHz samplerate.
+ * One 16bit item contains two samples of 8bits each. The bits of
+ * multiple samples are interleaved.
+ */
+static uint16_t sigma_deinterlace_100mhz_data(uint16_t indata, int idx)
+{
+ uint16_t outdata;
+
+ indata >>= idx;
+ outdata = 0;
+ outdata |= (indata >> (0 * 2 - 0)) & (1 << 0);
+ outdata |= (indata >> (1 * 2 - 1)) & (1 << 1);
+ outdata |= (indata >> (2 * 2 - 2)) & (1 << 2);
+ outdata |= (indata >> (3 * 2 - 3)) & (1 << 3);
+ outdata |= (indata >> (4 * 2 - 4)) & (1 << 4);
+ outdata |= (indata >> (5 * 2 - 5)) & (1 << 5);
+ outdata |= (indata >> (6 * 2 - 6)) & (1 << 6);
+ outdata |= (indata >> (7 * 2 - 7)) & (1 << 7);
+ return outdata;
+}
+
+/*
+ * Deinterlace sample data that was retrieved at 200MHz samplerate.
+ * One 16bit item contains four samples of 4bits each. The bits of
+ * multiple samples are interleaved.
+ */
+static uint16_t sigma_deinterlace_200mhz_data(uint16_t indata, int idx)
+{
+ uint16_t outdata;
+
+ indata >>= idx;
+ outdata = 0;
+ outdata |= (indata >> (0 * 4 - 0)) & (1 << 0);
+ outdata |= (indata >> (1 * 4 - 1)) & (1 << 1);
+ outdata |= (indata >> (2 * 4 - 2)) & (1 << 2);
+ outdata |= (indata >> (3 * 4 - 3)) & (1 << 3);
+ return outdata;
+}
+
+static void store_sr_sample(uint8_t *samples, int idx, uint16_t data)
+{
+ samples[2 * idx + 0] = (data >> 0) & 0xff;
+ samples[2 * idx + 1] = (data >> 8) & 0xff;
+}
+
+/*
+ * Local wrapper around sr_session_send() calls. Make sure to not send
+ * more samples to the session's datafeed than what was requested by a
+ * previously configured (optional) sample count.
+ */
+static void sigma_session_send(struct sr_dev_inst *sdi,
+ struct sr_datafeed_packet *packet)
+{
+ struct dev_context *devc;
+ struct sr_datafeed_logic *logic;
+ uint64_t send_now;
+
+ devc = sdi->priv;
+ if (devc->limit_samples) {
+ logic = (void *)packet->payload;
+ send_now = logic->length / logic->unitsize;
+ if (devc->sent_samples + send_now > devc->limit_samples) {
+ send_now = devc->limit_samples - devc->sent_samples;
+ logic->length = send_now * logic->unitsize;
+ }
+ if (!send_now)
+ return;
+ devc->sent_samples += send_now;
+ }
+
+ sr_session_send(sdi, packet);
+}
+
+/*
+ * This size translates to: event count (1K events per cluster), times
+ * the sample width (unitsize, 16bits per event), times the maximum
+ * number of samples per event.
+ */
+#define SAMPLES_BUFFER_SIZE (1024 * 2 * 4)
+