lkml.org 
[lkml]   [2019]   [Jan]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    SubjectRe: [PATCH v2] ALSA: hda/tegra: enable clock during probe
    From
    Date

    On 25/01/2019 11:06, Sameer Pujar wrote:
    > If CONFIG_PM is disabled or runtime PM calls are forbidden, the clocks
    > will not be ON. This could cause issue during probe, where hda init
    > setup is done. This patch enables clocks unconditionally during probe.
    >
    > Along with above, follwoing changes are done.
    > * enable runtime PM before exiting from probe work. This helps to avoid
    > usage of pm_runtime_get_sync/pm_runtime_put() in probe work.
    > * hda_tegra_disable_clocks() is moved out of CONFIG_PM_SLEEP check.
    > * runtime PM callbacks moved out of CONFIG_PM check
    >
    > Signed-off-by: Sameer Pujar <spujar@nvidia.com>
    > Reviewed-by: Ravindra Lokhande <rlokhande@nvidia.com>
    > Reviewed-by: Jon Hunter <jonathanh@nvidia.com>
    > ---
    > sound/pci/hda/hda_tegra.c | 26 +++++++++++++++++---------
    > 1 file changed, 17 insertions(+), 9 deletions(-)
    >
    > diff --git a/sound/pci/hda/hda_tegra.c b/sound/pci/hda/hda_tegra.c
    > index c8d18dc..ba6175f 100644
    > --- a/sound/pci/hda/hda_tegra.c
    > +++ b/sound/pci/hda/hda_tegra.c
    > @@ -219,7 +219,6 @@ static int hda_tegra_enable_clocks(struct hda_tegra *data)
    > return rc;
    > }
    >
    > -#ifdef CONFIG_PM_SLEEP
    > static void hda_tegra_disable_clocks(struct hda_tegra *data)
    > {
    > clk_disable_unprepare(data->hda2hdmi_clk);
    > @@ -227,6 +226,7 @@ static void hda_tegra_disable_clocks(struct hda_tegra *data)
    > clk_disable_unprepare(data->hda_clk);
    > }
    >
    > +#ifdef CONFIG_PM_SLEEP
    > /*
    > * power management
    > */
    > @@ -257,7 +257,6 @@ static int hda_tegra_resume(struct device *dev)
    > }
    > #endif /* CONFIG_PM_SLEEP */
    >
    > -#ifdef CONFIG_PM
    > static int hda_tegra_runtime_suspend(struct device *dev)
    > {
    > struct snd_card *card = dev_get_drvdata(dev);
    > @@ -283,7 +282,7 @@ static int hda_tegra_runtime_resume(struct device *dev)
    > int rc;
    >
    > rc = hda_tegra_enable_clocks(hda);
    > - if (rc != 0)
    > + if (rc)
    > return rc;
    > if (chip && chip->running) {
    > hda_tegra_init(hda);
    > @@ -292,7 +291,6 @@ static int hda_tegra_runtime_resume(struct device *dev)
    >
    > return 0;
    > }
    > -#endif /* CONFIG_PM */
    >
    > static const struct dev_pm_ops hda_tegra_pm = {
    > SET_SYSTEM_SLEEP_PM_OPS(hda_tegra_suspend, hda_tegra_resume)
    > @@ -551,9 +549,9 @@ static int hda_tegra_probe(struct platform_device *pdev)
    >
    > dev_set_drvdata(&pdev->dev, card);
    >
    > - pm_runtime_enable(hda->dev);
    > - if (!azx_has_pm_runtime(chip))
    > - pm_runtime_forbid(hda->dev);
    > + err = hda_tegra_enable_clocks(hda);
    > + if (err)
    > + goto out_free;

    We also need to think about power-domains here. Enabling the clocks
    might not be enough as the appropriate power-domain needs to be enabled.
    For 64-bit Tegra runtime-pm will handle the power-domains (assuming they
    are populated in device-tree). So I still think it is better we call
    pm_runtime_get_sync() at some point rather than just replying on
    enabling the clocks.

    Cheers
    Jon

    --
    nvpublic

    \
     
     \ /
      Last update: 2019-01-30 13:47    [W:5.531 / U:0.080 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site