[alsa-devel] [PATCH v3 00/13] ALSA: dice: use cache of stream formats to generate PCM rules/constraints

[Takashi Iwai]

On Wed, 02 May 2018 12:16:38 +0200,
Takashi Sakamoto wrote:
> 
> Hi,
> 
> This patchset updates my previous one:
> 
> [alsa-devel] [PATCH v2 00/11] ALSA: dice: use cache of stream formats to generate PCM rules/constraints
> http://mailman.alsa-project.org/pipermail/alsa-devel/2018-April/135330.html
> 
> Once, ALSA dice driver cached stream formats to generate PCM
> constraints/rules. The cache is created by changing current
> sampling transmission frequency step by step directly at unit
> probing process. This feature was dropped because it changes
> state of clock on target device thus it's against users'
> expectation[1].
> 
> However this is not necessarily convenient because reconfiguration
> of sampling rate is not available.
> 
> TC Applied Technologies (TCAT) has extended protocol for DICE
> interface, a.k.a EAP (Extended Application Protocol). In this
> extension, drivers can retrieve information of stream formats
> without changing state of target unit. Fortunately, this protocol
> is supported widely by many models.
> 
> This patchset regain the cache to generate PCM constraints/rules
> by using this protocol. Userspace applications can reconfigure
> sampling rate via ALSA PCM interface.
> 
> For units which doesn't support the extension, available set of
> sampling rate is still restricted at current sampling transmission
> frequency. This is also inconvenient and this patchset introduces a
> solution.
> 
> Structure for unit entry (struct ieee1394_device_id) has a member
> for unit-specific data. This patchset uses it for callback function
> to handle hard-coded stream format. In this time, I adopt this way
> for some known models produced by TC Electronic and Alesis. If users
> find their models still have restrictions in a point of available
> sampling transmission frequency, it's preferable to work for this
> way.
> 
> Changes from v2:
>  - use robust representation to calcurate mode of sampling
>    transmission frequency.
> 
> [1] [alsa-devel] [PATCH 0/6 v2] ALSA: dice: constrain PCM substreams to current sampling transfer frequency
> http://mailman.alsa-project.org/pipermail/alsa-devel/2016-February/104065.html
> 
> Takashi Sakamoto (13):
>   ALSA: dice: add cache of stream formats
>   ALSA: dice: add 'firewire' directory for proc nodes
>   ALSA: dice: add proc node for stream formation
>   ALSA: dice: cache stream formats at current mode of sampling
>     transmission frequency
>   ALSA: dice: add parameters of stream formats for models produced by TC
>     Electronic
>   ALSA: dice: add parameters of stream formats for models produced by
>     Alesis
>   ALSA: dice: use extended protocol to detect available stream formats
>   ALSA: dice: use cache of stream format to check running stream
>   ALSA: dice: add a helper function to restart all of available streams
>   ALSA: dice: enable to change current sampling transmission frequency
>   ALSA: dice: use stream formats to add MIDI substreams
>   ALSA: dice: use cache for PCM constraints and rules
>   ALSA: dice: remove local frag of force_two_pcms

Applied all patches now.  Thanks.


Takashi