• Sameer Pujar's avatar
    ASoC: tegra: Fix redundant PLLA and PLLA_OUT0 updates · e7658862
    Sameer Pujar authored
    Tegra audio graph card has many DAI links which connects internal
    AHUB modules and external audio codecs. Since these are DPCM links,
    hw_params() call in the machine driver happens for each connected
    BE link and PLLA is updated every time. This is not really needed
    for all links as only I/O link DAIs derive respective clocks from
    PLLA_OUT0 and thus from PLLA. Hence add checks to limit the clock
    updates to DAIs over I/O links.
    
    This found to be fixing a DMIC clock discrepancy which is suspected
    to happen because of back to back quick PLLA and PLLA_OUT0 rate
    updates. This was observed on Jetson TX2 platform where DMIC clock
    ended up with unexpected value.
    
    Fixes: 202e2f77 ("ASoC: tegra: Add audio graph based card driver")
    Cc: stable@vger.kernel.org
    Signed-off-by: default avatarSameer Pujar <spujar@nvidia.com>
    Link: https://lore.kernel.org/r/1694098945-32760-3-git-send-email-spujar@nvidia.comSigned-off-by: default avatarMark Brown <broonie@kernel.org>
    e7658862
tegra_audio_graph_card.c 6.56 KB