Re: [PATCH v8 19/22] ASoC: tegra: Enable audio mclk during tegra_asoc_utils_init

[Sameer Pujar]

On 1/19/2020 8:44 PM, Dmitry Osipenko wrote:
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>
>
> 14.01.2020 10:24, Sowjanya Komatineni ÐÐÑÐÑ:
> > Tegra PMC clock clk_out_1 is dedicated for audio mclk from Tegra30
> > through Tegra210 and currently Tegra clock driver keeps the audio
> > mclk enabled.
> >
> > With the move of PMC clocks from clock driver into pmc driver,
> > audio mclk enable from clock driver is removed and this should be
> > taken care by the audio driver.
> >
> > tegra_asoc_utils_init calls tegra_asoc_utils_set_rate and audio mclk
> > rate configuration is not needed during init and set_rate is actually
> > done during hw_params callback.
> >
> > So, this patch removes tegra_asoc_utils_set_rate call and just leaves
> > the audio mclk enabled.
> >
> > Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
> > ---
> >   sound/soc/tegra/tegra_asoc_utils.c | 11 +++++++++--
> >   1 file changed, 9 insertions(+), 2 deletions(-)
> >
> > diff --git a/sound/soc/tegra/tegra_asoc_utils.c b/sound/soc/tegra/tegra_asoc_utils.c
> > index 1dce5ad6e665..99584970f5f4 100644
> > --- a/sound/soc/tegra/tegra_asoc_utils.c
> > +++ b/sound/soc/tegra/tegra_asoc_utils.c
> > @@ -216,9 +216,16 @@ int tegra_asoc_utils_init(struct tegra_asoc_utils_data *data,
> >                data->clk_cdev1 = clk_out_1;
> >        }
> >
> > -     ret = tegra_asoc_utils_set_rate(data, 44100, 256 * 44100);
> > -     if (ret)
> > +     /*
> > +      * FIXME: There is some unknown dependency between audio mclk disable
> > +      * and suspend-resume functionality on Tegra30, although audio mclk is
> > +      * only needed for audio.
> > +      */
> > +     ret = clk_prepare_enable(data->clk_cdev1);
> > +     if (ret) {
> > +             dev_err(data->dev, "Can't enable cdev1: %d\n", ret);
> >                return ret;
> > +     }
> >
> >        return 0;
> >   }
> Shouldn't the clock be disabled on driver's removal?

I am not sure if we really need to do in this series as it does not 
change the behavior from what was there earlier. Also there is already a 
FIXME item here and we end up adding clock disable in remove() path of 
multiple drivers, which is going to be removed once we address FIXME.