Hi Joao, On Apr 17, 2024 at 15:41:38 -0300, Joao Paulo Goncalves wrote: > From: Joao Paulo Goncalves <joao.goncalves@xxxxxxxxxxx> > > When using davinci-mcasp as CPU DAI with simple-card, there are some > conditions that cause simple-card to finish registering a sound card before > davinci-mcasp finishes registering all sound components. This creates a > non-working sound card from userspace with no problem indication apart > from not being able to play/record audio on a PCM stream. The issue > arises during simultaneous probe execution of both drivers. Specifically, > the simple-card driver, awaiting a CPU DAI, proceeds as soon as > davinci-mcasp registers its DAI. However, this process can lead to the > client mutex lock (client_mutex in soc-core.c) being held or davinci-mcasp > being preempted before PCM DMA registration on davinci-mcasp finishes. > This situation occurs when the probes of both drivers run concurrently. > Below is the code path for this condition. To solve the issue, defer > davinci-mcasp CPU DAI registration to the last step in the audio part of > it. This way, simple-card CPU DAI parsing will be deferred until all > audio components are registered. Good catch, thanks for the fix. Reviewed-by: Jai Luthra <j-luthra@xxxxxx> > > Fail Code Path: > > simple-card.c: probe starts > simple-card.c: simple_dai_link_of: simple_parse_node(..,cpu,..) returns EPROBE_DEFER, no CPU DAI yet > davinci-mcasp.c: probe starts > davinci-mcasp.c: devm_snd_soc_register_component() register CPU DAI > simple-card.c: probes again, finish CPU DAI parsing and call devm_snd_soc_register_card() > simple-card.c: finish probe > davinci-mcasp.c: *dma_pcm_platform_register() register PCM DMA > davinci-mcasp.c: probe finish > > Cc: stable@xxxxxxxxxxxxxxx > Fixes: 9fbd58cf4ab0 ("ASoC: davinci-mcasp: Choose PCM driver based on configured DMA controller") > Signed-off-by: Joao Paulo Goncalves <joao.goncalves@xxxxxxxxxxx> > --- > sound/soc/ti/davinci-mcasp.c | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > diff --git a/sound/soc/ti/davinci-mcasp.c b/sound/soc/ti/davinci-mcasp.c > index b892d66f78470..1e760c3155213 100644 > --- a/sound/soc/ti/davinci-mcasp.c > +++ b/sound/soc/ti/davinci-mcasp.c > @@ -2417,12 +2417,6 @@ static int davinci_mcasp_probe(struct platform_device *pdev) > > mcasp_reparent_fck(pdev); > > - ret = devm_snd_soc_register_component(&pdev->dev, &davinci_mcasp_component, > - &davinci_mcasp_dai[mcasp->op_mode], 1); > - > - if (ret != 0) > - goto err; > - > ret = davinci_mcasp_get_dma_type(mcasp); > switch (ret) { > case PCM_EDMA: > @@ -2449,6 +2443,12 @@ static int davinci_mcasp_probe(struct platform_device *pdev) > goto err; > } > > + ret = devm_snd_soc_register_component(&pdev->dev, &davinci_mcasp_component, > + &davinci_mcasp_dai[mcasp->op_mode], 1); > + > + if (ret != 0) > + goto err; > + > no_audio: > ret = davinci_mcasp_init_gpiochip(mcasp); > if (ret) { > -- > 2.34.1 > -- Thanks, Jai GPG Fingerprint: 4DE0 D818 E5D5 75E8 D45A AFC5 43DE 91F9 249A 7145
Attachment:
signature.asc
Description: PGP signature