From f65be911c0e13fab28919e17c9fa00c38dc4ff2f Mon Sep 17 00:00:00 2001 From: Takashi Sakamoto Date: Sat, 19 Sep 2015 11:21:58 +0900 Subject: [PATCH] ALSA: firewire-lib: add helper functions to set positions of data channels In IEC 61883-6, several types of data are available in AM824 format. The data is transferred in each data channel. The position of data channel in data block differs depending on model. Current implementation has an array to map the index of data channel in an data block to the position of actual data channel. The implementation allows each driver to access the mapping directly. In later commit, the mapping is in specific structure pushed into an opaque pointer. Helper functions are required. This commit adds the helper functions for this purpose. In IEC 61883-6, AM824 format supports many data types, while this specification easily causes over-engineering. Current AM824 implementation is allowed to handle two types of data, Multi Bit Linear Audio data (=PCM samples) and MIDI conformant data (=MIDI messages). Signed-off-by: Takashi Sakamoto Signed-off-by: Takashi Iwai --- sound/firewire/amdtp-am824.c | 28 ++++++++++++++++++++++++++++ sound/firewire/amdtp-am824.h | 6 ++++++ sound/firewire/bebob/bebob_stream.c | 5 +++-- sound/firewire/dice/dice-stream.c | 5 +++-- 4 files changed, 40 insertions(+), 4 deletions(-) diff --git a/sound/firewire/amdtp-am824.c b/sound/firewire/amdtp-am824.c index 7adaba356579..5d99a9921d50 100644 --- a/sound/firewire/amdtp-am824.c +++ b/sound/firewire/amdtp-am824.c @@ -52,6 +52,34 @@ int amdtp_am824_set_parameters(struct amdtp_stream *s, unsigned int rate, } EXPORT_SYMBOL_GPL(amdtp_am824_set_parameters); +/** + * amdtp_am824_set_pcm_position - set an index of data channel for a channel + * of PCM frame + * @s: the AMDTP stream + * @index: the index of data channel in an data block + * @position: the channel of PCM frame + */ +void amdtp_am824_set_pcm_position(struct amdtp_stream *s, unsigned int index, + unsigned int position) +{ + if (index < s->pcm_channels) + s->pcm_positions[index] = position; +} +EXPORT_SYMBOL_GPL(amdtp_am824_set_pcm_position); + +/** + * amdtp_am824_set_midi_position - set a index of data channel for MIDI + * conformant data channel + * @s: the AMDTP stream + * @position: the index of data channel in an data block + */ +void amdtp_am824_set_midi_position(struct amdtp_stream *s, + unsigned int position) +{ + s->midi_position = position; +} +EXPORT_SYMBOL_GPL(amdtp_am824_set_midi_position); + /** * amdtp_am824_add_pcm_hw_constraints - add hw constraints for PCM substream * @s: the AMDTP stream for AM824 data block, must be initialized. diff --git a/sound/firewire/amdtp-am824.h b/sound/firewire/amdtp-am824.h index 4aaed9048d82..7c21e9972fad 100644 --- a/sound/firewire/amdtp-am824.h +++ b/sound/firewire/amdtp-am824.h @@ -10,6 +10,12 @@ int amdtp_am824_set_parameters(struct amdtp_stream *s, unsigned int rate, unsigned int midi_ports, bool double_pcm_frames); +void amdtp_am824_set_pcm_position(struct amdtp_stream *s, unsigned int index, + unsigned int position); + +void amdtp_am824_set_midi_position(struct amdtp_stream *s, + unsigned int position); + int amdtp_am824_add_pcm_hw_constraints(struct amdtp_stream *s, struct snd_pcm_runtime *runtime); diff --git a/sound/firewire/bebob/bebob_stream.c b/sound/firewire/bebob/bebob_stream.c index fa510f30cf8f..cf6402d371e7 100644 --- a/sound/firewire/bebob/bebob_stream.c +++ b/sound/firewire/bebob/bebob_stream.c @@ -338,7 +338,7 @@ map_data_channels(struct snd_bebob *bebob, struct amdtp_stream *s) err = -ENOSYS; goto end; } - s->midi_position = stm_pos; + amdtp_am824_set_midi_position(s, stm_pos); midi = stm_pos; break; /* for PCM data channel */ @@ -358,7 +358,8 @@ map_data_channels(struct snd_bebob *bebob, struct amdtp_stream *s) err = -ENOSYS; goto end; } - s->pcm_positions[location] = stm_pos; + amdtp_am824_set_pcm_position(s, location, + stm_pos); break; } } diff --git a/sound/firewire/dice/dice-stream.c b/sound/firewire/dice/dice-stream.c index 89483818785e..2108f7f1a764 100644 --- a/sound/firewire/dice/dice-stream.c +++ b/sound/firewire/dice/dice-stream.c @@ -141,8 +141,9 @@ static int start_stream(struct snd_dice *dice, struct amdtp_stream *stream, pcm_chs /= 2; for (i = 0; i < pcm_chs; i++) { - stream->pcm_positions[i] = i * 2; - stream->pcm_positions[i + pcm_chs] = i * 2 + 1; + amdtp_am824_set_pcm_position(stream, i, i * 2); + amdtp_am824_set_pcm_position(stream, i + pcm_chs, + i * 2 + 1); } } -- 2.20.1