We are currently using simple-audio-card on the Allwinner A64 SoC. The digital audio codec there (sun8i-codec) has 3 AIFs, one each for the CPU, the modem, and Bluetooth. Adding support for the secondary AIFs requires adding codec2codec DAI links.
Since the modem and bt-sco codec DAI drivers only have one set of possible PCM parameters (namely, 8kHz mono S16LE), there's no real need for a machine driver to specify the DAI link configuration. The parameters for these "simple" DAI links can be chosen automatically.
This series adds a single "codec-to-codec" property to the simple-audio-card binding, which does exactly what it says. It works out rather nicely without making the device tree binding too complicated.
The first patch fixes a bug I found while implementing this feature.
I tried to reuse as much code as possible, so the middle two patches refactor a couple of helper functions to be more generic.
Finally, the last patch adds the new feature and its documentation.
Samuel Holland (4): ASoC: codec2codec: avoid invalid/double-free of pcm runtime ALSA: pcm: Make snd_pcm_limit_hw_rates take hw directly ASoC: pcm: Export parameter intersection logic ASoC: simple-card: Add support for codec-to-codec dai_links
.../devicetree/bindings/sound/simple-card.txt | 1 + Documentation/sound/soc/codec-to-codec.rst | 9 ++- .../drm/bridge/synopsys/dw-hdmi-ahb-audio.c | 2 +- include/sound/pcm.h | 2 +- include/sound/simple_card_utils.h | 1 + include/sound/soc.h | 3 + sound/arm/aaci.c | 2 +- sound/arm/pxa2xx-ac97.c | 2 +- sound/core/pcm_misc.c | 14 ++--- sound/firewire/dice/dice-pcm.c | 2 +- sound/firewire/digi00x/digi00x-pcm.c | 2 +- sound/firewire/fireworks/fireworks_pcm.c | 2 +- sound/firewire/motu/motu-pcm.c | 2 +- sound/firewire/tascam/tascam-pcm.c | 2 +- sound/pci/atiixp.c | 2 +- sound/pci/cs5535audio/cs5535audio_pcm.c | 4 +- sound/pci/hda/hda_controller.c | 4 +- sound/pci/intel8x0.c | 2 +- sound/pci/sis7019.c | 2 +- sound/pci/via82xx.c | 4 +- sound/soc/generic/simple-card-utils.c | 39 +++++++++++++ sound/soc/generic/simple-card.c | 12 ++++ sound/soc/soc-dapm.c | 3 - sound/soc/soc-pcm.c | 57 +++++++++++++------ sound/usb/caiaq/audio.c | 4 +- 25 files changed, 130 insertions(+), 49 deletions(-)