Re: [PATCH v3 1/3] ALSA: hda/tegra: Fix Tegra194 HDA reset failure

[Sameer Pujar <spujar@xxxxxxxxxx>]

On 12/23/2021 12:10 AM, Dmitry Osipenko wrote:
> 22.12.2021 07:35, Sameer Pujar пишет:
> > HDA regression is recently reported on Tegra194 based platforms.
> > This happens because "hda2codec_2x" reset does not really exist
> > in Tegra194 and it causes probe failure. All the HDA based audio
> > tests fail at the moment. This underlying issue is exposed by
> > commit c045ceb5a145 ("reset: tegra-bpmp: Handle errors in BPMP
> > response") which now checks return code of BPMP command response.
> > Fix this issue by skipping unavailable reset on Tegra194.
> >
> > Signed-off-by: Sameer Pujar <spujar@xxxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx
> > Depends-on: 87f0e46e7559 ("ALSA: hda/tegra: Reset hardware")
> Is "Depends-on" a valid tag? I can't find it in Documentation/.

I do find the usage of the tag in many commits though there is no 
reference of this in doc. I always thought it would act as a reference 
when commits get pulled to other branches. If this is not true and it 
does not mean anything, I will drop this.

> > ---
> >   sound/pci/hda/hda_tegra.c | 45 ++++++++++++++++++++++++++++++++++++---------
> >   1 file changed, 36 insertions(+), 9 deletions(-)
> >
> > diff --git a/sound/pci/hda/hda_tegra.c b/sound/pci/hda/hda_tegra.c
> > index ea700395..7c3df54 100644
> > --- a/sound/pci/hda/hda_tegra.c
> > +++ b/sound/pci/hda/hda_tegra.c
> > @@ -68,14 +68,20 @@
> >    */
> >   #define TEGRA194_NUM_SDO_LINES         4
> >
> > +struct hda_tegra_soc {
> > +     bool has_hda2codec_2x_reset;
> > +};
> > +
> >   struct hda_tegra {
> >        struct azx chip;
> >        struct device *dev;
> > -     struct reset_control *reset;
> > +     struct reset_control_bulk_data resets[3];
> >        struct clk_bulk_data clocks[3];
> > +     unsigned int nresets;
> >        unsigned int nclocks;
> >        void __iomem *regs;
> >        struct work_struct probe_work;
> > +     const struct hda_tegra_soc *data;
> >   };
> >
> >   #ifdef CONFIG_PM
> > @@ -170,7 +176,7 @@ static int __maybe_unused hda_tegra_runtime_resume(struct device *dev)
> >        int rc;
> >
> >        if (!chip->running) {
> > -             rc = reset_control_assert(hda->reset);
> > +             rc = reset_control_bulk_assert(hda->nresets, hda->resets);
> >                if (rc)
> >                        return rc;
> >        }
> > @@ -187,7 +193,7 @@ static int __maybe_unused hda_tegra_runtime_resume(struct device *dev)
> >        } else {
> >                usleep_range(10, 100);
> >
> > -             rc = reset_control_deassert(hda->reset);
> > +             rc = reset_control_bulk_deassert(hda->nresets, hda->resets);
> >                if (rc)
> >                        return rc;
> >        }
> > @@ -427,9 +433,17 @@ static int hda_tegra_create(struct snd_card *card,
> >        return 0;
> >   }
> >
> > +static const struct hda_tegra_soc tegra30_data = {
> > +     .has_hda2codec_2x_reset = true,
> > +};
> > +
> > +static const struct hda_tegra_soc tegra194_data = {
> > +     .has_hda2codec_2x_reset = false,
> > +};
> > +
> >   static const struct of_device_id hda_tegra_match[] = {
> > -     { .compatible = "nvidia,tegra30-hda" },
> > -     { .compatible = "nvidia,tegra194-hda" },
> > +     { .compatible = "nvidia,tegra30-hda", .data = &tegra30_data },
> > +     { .compatible = "nvidia,tegra194-hda", .data = &tegra194_data },
> >        {},
> >   };
> >   MODULE_DEVICE_TABLE(of, hda_tegra_match);
> > @@ -449,6 +463,10 @@ static int hda_tegra_probe(struct platform_device *pdev)
> >        hda->dev = &pdev->dev;
> >        chip = &hda->chip;
> >
> > +     hda->data = of_device_get_match_data(&pdev->dev);
> > +     if (!hda->data)
> > +             return -EINVAL;
> hda->data can't ever be NULL because all hda_tegra_match[] compatibles
> above have .data assigned. Technically this check is redundant.

Will remove.

> Thierry suggested previously to name it "hda->soc", like we usually do
> it in other drivers.

Previously I renamed strcture, but didn't update the member name. Will 
update.

> >        err = snd_card_new(&pdev->dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
> >                           THIS_MODULE, 0, &card);
> >        if (err < 0) {
> > @@ -456,11 +474,20 @@ static int hda_tegra_probe(struct platform_device *pdev)
> >                return err;
> >        }
> >
> > -     hda->reset = devm_reset_control_array_get_exclusive(&pdev->dev);
> > -     if (IS_ERR(hda->reset)) {
> > -             err = PTR_ERR(hda->reset);
> > +     hda->resets[hda->nresets++].id = "hda";
> > +     hda->resets[hda->nresets++].id = "hda2hdmi";
> > +     /*
> > +      * "hda2codec_2x" reset is not present on Tegra194. Though DT would
> > +      * be updated to reflect this, but to have backward compatibility
> > +      * below is necessary.
> > +      */
> > +     if (hda->data->has_hda2codec_2x_reset)
> > +             hda->resets[hda->nresets++].id = "hda2codec_2x";
> > +
> > +     err = devm_reset_control_bulk_get_exclusive(&pdev->dev, hda->nresets,
> > +                                                 hda->resets);
> > +     if (err)
> >                goto out_free;
> > -     }
> >
> >        hda->clocks[hda->nclocks++].id = "hda";
> >        hda->clocks[hda->nclocks++].id = "hda2hdmi";
> Not sure whether the above nits worth making v4. I'll leave it up to you
> and other reviewers to decide.
>
> Overall this patch looks good to me, thank you.
>
> Reviewed-by: Dmitry Osipenko <digetx@xxxxxxxxx>