--- /dev/null
+/*
+ * ff-stream.c - a part of driver for RME Fireface series
+ *
+ * Copyright (c) 2015-2017 Takashi Sakamoto
+ *
+ * Licensed under the terms of the GNU General Public License, version 2.
+ */
+
+#include "ff.h"
+
+#define CALLBACK_TIMEOUT_MS 200
+
+static int get_rate_mode(unsigned int rate, unsigned int *mode)
+{
+ int i;
+
+ for (i = 0; i < CIP_SFC_COUNT; i++) {
+ if (amdtp_rate_table[i] == rate)
+ break;
+ }
+
+ if (i == CIP_SFC_COUNT)
+ return -EINVAL;
+
+ *mode = ((int)i - 1) / 2;
+
+ return 0;
+}
+
+/*
+ * Fireface 400 manages isochronous channel number in 3 bit field. Therefore,
+ * we can allocate between 0 and 7 channel.
+ */
+static int keep_resources(struct snd_ff *ff, unsigned int rate)
+{
+ int mode;
+ int err;
+
+ err = get_rate_mode(rate, &mode);
+ if (err < 0)
+ return err;
+
+ /* Keep resources for in-stream. */
+ err = amdtp_ff_set_parameters(&ff->tx_stream, rate,
+ ff->spec->pcm_capture_channels[mode]);
+ if (err < 0)
+ return err;
+ ff->tx_resources.channels_mask = 0x00000000000000ffuLL;
+ err = fw_iso_resources_allocate(&ff->tx_resources,
+ amdtp_stream_get_max_payload(&ff->tx_stream),
+ fw_parent_device(ff->unit)->max_speed);
+ if (err < 0)
+ return err;
+
+ /* Keep resources for out-stream. */
+ err = amdtp_ff_set_parameters(&ff->rx_stream, rate,
+ ff->spec->pcm_playback_channels[mode]);
+ if (err < 0)
+ return err;
+ ff->rx_resources.channels_mask = 0x00000000000000ffuLL;
+ err = fw_iso_resources_allocate(&ff->rx_resources,
+ amdtp_stream_get_max_payload(&ff->rx_stream),
+ fw_parent_device(ff->unit)->max_speed);
+ if (err < 0)
+ fw_iso_resources_free(&ff->tx_resources);
+
+ return err;
+}
+
+static void release_resources(struct snd_ff *ff)
+{
+ fw_iso_resources_free(&ff->tx_resources);
+ fw_iso_resources_free(&ff->rx_resources);
+}
+
+static inline void finish_session(struct snd_ff *ff)
+{
+ ff->spec->protocol->finish_session(ff);
+ ff->spec->protocol->switch_fetching_mode(ff, false);
+}
+
+static int init_stream(struct snd_ff *ff, enum amdtp_stream_direction dir)
+{
+ int err;
+ struct fw_iso_resources *resources;
+ struct amdtp_stream *stream;
+
+ if (dir == AMDTP_IN_STREAM) {
+ resources = &ff->tx_resources;
+ stream = &ff->tx_stream;
+ } else {
+ resources = &ff->rx_resources;
+ stream = &ff->rx_stream;
+ }
+
+ err = fw_iso_resources_init(resources, ff->unit);
+ if (err < 0)
+ return err;
+
+ err = amdtp_ff_init(stream, ff->unit, dir);
+ if (err < 0)
+ fw_iso_resources_destroy(resources);
+
+ return err;
+}
+
+static void destroy_stream(struct snd_ff *ff, enum amdtp_stream_direction dir)
+{
+ if (dir == AMDTP_IN_STREAM) {
+ amdtp_stream_destroy(&ff->tx_stream);
+ fw_iso_resources_destroy(&ff->tx_resources);
+ } else {
+ amdtp_stream_destroy(&ff->rx_stream);
+ fw_iso_resources_destroy(&ff->rx_resources);
+ }
+}
+
+int snd_ff_stream_init_duplex(struct snd_ff *ff)
+{
+ int err;
+
+ err = init_stream(ff, AMDTP_OUT_STREAM);
+ if (err < 0)
+ goto end;
+
+ err = init_stream(ff, AMDTP_IN_STREAM);
+ if (err < 0)
+ destroy_stream(ff, AMDTP_OUT_STREAM);
+end:
+ return err;
+}
+
+/*
+ * This function should be called before starting streams or after stopping
+ * streams.
+ */
+void snd_ff_stream_destroy_duplex(struct snd_ff *ff)
+{
+ destroy_stream(ff, AMDTP_IN_STREAM);
+ destroy_stream(ff, AMDTP_OUT_STREAM);
+}
+
+int snd_ff_stream_start_duplex(struct snd_ff *ff, unsigned int rate)
+{
+ unsigned int curr_rate;
+ enum snd_ff_clock_src src;
+ int err;
+
+ if (ff->substreams_counter == 0)
+ return 0;
+
+ err = ff->spec->protocol->get_clock(ff, &curr_rate, &src);
+ if (err < 0)
+ return err;
+ if (curr_rate != rate ||
+ amdtp_streaming_error(&ff->tx_stream) ||
+ amdtp_streaming_error(&ff->rx_stream)) {
+ finish_session(ff);
+
+ amdtp_stream_stop(&ff->tx_stream);
+ amdtp_stream_stop(&ff->rx_stream);
+
+ release_resources(ff);
+ }
+
+ /*
+ * Regardless of current source of clock signal, drivers transfer some
+ * packets. Then, the device transfers packets.
+ */
+ if (!amdtp_stream_running(&ff->rx_stream)) {
+ err = keep_resources(ff, rate);
+ if (err < 0)
+ goto error;
+
+ err = ff->spec->protocol->begin_session(ff, rate);
+ if (err < 0)
+ goto error;
+
+ err = amdtp_stream_start(&ff->rx_stream,
+ ff->rx_resources.channel,
+ fw_parent_device(ff->unit)->max_speed);
+ if (err < 0)
+ goto error;
+
+ if (!amdtp_stream_wait_callback(&ff->rx_stream,
+ CALLBACK_TIMEOUT_MS)) {
+ err = -ETIMEDOUT;
+ goto error;
+ }
+
+ err = ff->spec->protocol->switch_fetching_mode(ff, true);
+ if (err < 0)
+ goto error;
+ }
+
+ if (!amdtp_stream_running(&ff->tx_stream)) {
+ err = amdtp_stream_start(&ff->tx_stream,
+ ff->tx_resources.channel,
+ fw_parent_device(ff->unit)->max_speed);
+ if (err < 0)
+ goto error;
+
+ if (!amdtp_stream_wait_callback(&ff->tx_stream,
+ CALLBACK_TIMEOUT_MS)) {
+ err = -ETIMEDOUT;
+ goto error;
+ }
+ }
+
+ return 0;
+error:
+ amdtp_stream_stop(&ff->tx_stream);
+ amdtp_stream_stop(&ff->rx_stream);
+
+ finish_session(ff);
+ release_resources(ff);
+
+ return err;
+}
+
+void snd_ff_stream_stop_duplex(struct snd_ff *ff)
+{
+ if (ff->substreams_counter > 0)
+ return;
+
+ amdtp_stream_stop(&ff->tx_stream);
+ amdtp_stream_stop(&ff->rx_stream);
+ finish_session(ff);
+ release_resources(ff);
+}
+
+void snd_ff_stream_update_duplex(struct snd_ff *ff)
+{
+ /* The device discontinue to transfer packets. */
+ amdtp_stream_pcm_abort(&ff->tx_stream);
+ amdtp_stream_stop(&ff->tx_stream);
+
+ amdtp_stream_pcm_abort(&ff->rx_stream);
+ amdtp_stream_stop(&ff->rx_stream);
+
+ fw_iso_resources_update(&ff->tx_resources);
+ fw_iso_resources_update(&ff->rx_resources);
+}