[alsa-devel] [PATCH v4 0/2] ALSA controls management using index/device/sub-devices fields

[Arnaud Pouliquen]

Previous discussions summary:
 - Topic of  the patchset: 
 	Patch concerns ASoc DAI drivers.
        Aim is to be able to instantiate PCM control using device field according 
        to the associated PCM char device.  For this, a relationship between DAIs PCM 
        control and PCM char device needs to be establish.
        => Proposal is to add field in DAI driver struct to declare PCM controls that
	need to be linked to PCM character device on DAI link probing.

  - Limitation of the patchset:
  	This patchset seems only a first step as 2 concerns are been highlighted:
         - Patch is limited to "static" DAI-link. This not responds to backend (no_pcm dai links) and 
         some none-DAI codecs, that could register PCm controls. 
         In theses cases it is not possible to establish relationship during probe.
         	=> No solution proposed for time beeing.

         - This patchset does not fix conflict of 2 "identical" PCM controls declared by 2 drivers. 
          For instance, a conflict can exist between a  PCM control created in DAI driver 
          and the same control declared in a codec driver. As index field is forced to 0, prefix
          should be used in codec.
        	=> To discuss solution in a separate thread as issue already present without this patchset 
                	several approaches seem possible like using index field ( control auto indexation in
                        ASoC) or prefix in Naming. 
V4:
 - [PATCH v4 1/2] ASoC: core: allow DAI PCM controls bound to PCM device
 	Fix and rework error management in soc_link_dai_pcm_controls function.
 - [PATCH v4 2/2] ASoC: sti: bind pcm controls to pcm device. 
 	No change since V2.

V3:
 - [PATCH v3 1/2] ASoC: core: allow DAI PCM controls bound to PCM device
 	Code optimization based on Takashi Sakamoto suggestion
 - [RFC V2 3/3]   ASoC: hdmi-codec: Example of PCM control bound to PCM device for multi
	patch suppressed as it was send as example in previous version. Patch is valid but
        can have impact on existing drivers as control device field value is updated 
  - [PATCH v3 2/2] ASoC: sti: bind pcm controls to pcm device. 
 	No change vs V2

V2:
http://www.spinics.net/lists/alsa-devel/msg57045.html

Aim of this version is to continue discussion on DAI PCM control focused on ASoC drivers.
In this V2  implementation in Soc-core is simplified to limit impact on existing code.

 Update of the RFC V1 based on discussions:
 - [RFC 4/4] iecset: allow to select control with device and sub-device numbers
 	no more part of the RFC V2, will be discussed in a separate thread
 - [RFC 2/4] ALSA: control: increment index field for duplicated control.
 	no more part of the RFC V2, no more need as RFC subject is PCM controls

- [RFC V2 1/3] ASoC: core: allow DAI PCM controls bound to PCM device
	Patch reworked from V1 to simplify implementation
        - Binding is not done for Dai links tagged with no_pcm (DPCM).
        - no more possibility to add the controls after the DAI link probing.

- [RFC V2 2/3]   ASoC: sti: bind PCM controls to PCM device.
- [RFC V2 3/3]   ASoC: hdmi-codec: Example of PCM control bound to PCM device for multi
        Example of implementation in STI DAI driver and HDMI-codec drivers
     
V1: 
 http://www.spinics.net/lists/alsa-devel/msg56479.html

 1) Alsa-utils patch

- iecset: allow to select control with device and sub-device numbers
  This patch allows to access to 2 iec controls differentiated by
  device/sub-devices numbers
=> For me, this patch is mandatory to be able to address the ASoC IEC
   controls, in case of no fix is implemented to allows index field
   update in ASoC.

2) Alsa driver patches
  - ASoC: core: allow PCM control binding to PCM device
  	Add relationship between DAIs PCM controls and PCM device.

  - ALSA: control: increment index field for duplicated control.
   	Generic implementation of the patch proposed in HDA driver
        (http://git.kernel.org/cgit/linux/kernel/git/tiwai/sound.git/commit/?id=ea9b43add)

  - ASoC: sti: use bind_pcm_ctl
  	implementation of bind_pcm_ctl for sti driver.

Arnaud Pouliquen (2):
  ASoC: core: allow DAI PCM controls bound to PCM device
  ASoC: sti: bind pcm controls to pcm device.

 include/sound/soc-dai.h      |  4 ++++
 sound/soc/soc-core.c         | 35 +++++++++++++++++++++++++++++++++++
 sound/soc/sti/sti_uniperif.c | 33 ++++-----------------------------
 3 files changed, 43 insertions(+), 29 deletions(-)

-- 
1.9.1