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| author | Takashi Sakamoto <o-takashi@sakamocchi.jp> | 2015-09-19 11:21:50 +0900 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2015-09-29 12:35:46 +0200 |
| commit | 27ec83b5c6ac08599240ec9a95286e79d6ea9e51 (patch) | |
| tree | 35d0f2fba9c7ecc3def778d61e79f694c319febb /sound/firewire/amdtp.c | |
| parent | 547e631ce3886175a33b5ccf67729bdd18e9b7e0 (diff) | |
| download | linux-27ec83b5c6ac08599240ec9a95286e79d6ea9e51.tar.bz2 | |
ALSA: firewire-lib: add an argument for Dice's dual wire mode
In IEC 61883-6, one data block represents one event. In ALSA, the event is
one PCM frame. Therefore, when processing one data block, current
implementation counts one PCM frame.
On the other hand, Dice platform has a quirk called as 'dual wire' at
higher sampling rate. In detail, see comment of commit 6eb6c81eee2a
("ALSA: dice: Split stream functionality into a file").
Currently, to handle this quirk, AMDTP stream structure has a
'double_pcm_frames' member. When this is enabled, two PCM frames are
counted. Each driver set this flag by accessing the structure member
directly.
In future commit, some members related to AM824 data block will be moved
to specific structure, to separate packet streaming layer and data block
processing layer. The access will be limited by opaque pointer.
For this reason, this commit adds an argument into
amdtp_stream_set_parameter() to set the flag.
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/firewire/amdtp.c')
| -rw-r--r-- | sound/firewire/amdtp.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/sound/firewire/amdtp.c b/sound/firewire/amdtp.c index 2bacb5173ff8..094982f7c0fd 100644 --- a/sound/firewire/amdtp.c +++ b/sound/firewire/amdtp.c @@ -193,6 +193,7 @@ EXPORT_SYMBOL(amdtp_stream_add_pcm_hw_constraints); * @pcm_channels: the number of PCM samples in each data block, to be encoded * as AM824 multi-bit linear audio * @midi_ports: the number of MIDI ports (i.e., MPX-MIDI Data Channels) + * @double_pcm_frames: one data block transfers two PCM frames * * The parameters must be set before the stream is started, and must not be * changed while the stream is running. @@ -200,7 +201,8 @@ EXPORT_SYMBOL(amdtp_stream_add_pcm_hw_constraints); int amdtp_stream_set_parameters(struct amdtp_stream *s, unsigned int rate, unsigned int pcm_channels, - unsigned int midi_ports) + unsigned int midi_ports, + bool double_pcm_frames) { unsigned int i, sfc, midi_channels; |