Re: [PATCH 2/5] soundwire: qcom: enable runtime pm before controller is registered

[Srinivas Kandagatla]

On 09/02/2023 15:21, Pierre-Louis Bossart wrote:
> On 2/9/23 07:13, Srinivas Kandagatla wrote:
> > Registering controller even before pm runtime is enabled will result
> > in pm runtime underflow warnings. Fix this by properly moving
> > the runtime pm enable before registering controller.
>
> That seems very odd. The Intel code configures the pm_runtime stuff
> *after* the call to sdw_bus_master_add(), and we've not seen any
> underflow warnings? We even configure pm_runtime after starting the bus.
> Likewise for peripherals the pm_runtime part is enabled after the device
> is initialized.
This was very random during bootup, Let me see if I can collect a back 
trace after reverting this patch..

--srini

> Not following the problem and suggested solution.
>
> > Fixes: 74e79da9fd46 ("soundwire: qcom: add runtime pm support")
> > Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
> > ---
> >   drivers/soundwire/qcom.c | 12 ++++++------
> >   1 file changed, 6 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
> > index 9d8ae77bad0a..b2363839624c 100644
> > --- a/drivers/soundwire/qcom.c
> > +++ b/drivers/soundwire/qcom.c
> > @@ -1417,6 +1417,12 @@ static int qcom_swrm_probe(struct platform_device *pdev)
> >   		}
> >   	}
> >   
> > +	pm_runtime_set_autosuspend_delay(dev, 3000);
> > +	pm_runtime_use_autosuspend(dev);
> > +	pm_runtime_mark_last_busy(dev);
> > +	pm_runtime_set_active(dev);
> > +	pm_runtime_enable(dev);
> > +
> >   	ret = sdw_bus_master_add(&ctrl->bus, dev, dev->fwnode);
> >   	if (ret) {
> >   		dev_err(dev, "Failed to register Soundwire controller (%d)\n",
> > @@ -1435,12 +1441,6 @@ static int qcom_swrm_probe(struct platform_device *pdev)
> >   		 (ctrl->version >> 24) & 0xff, (ctrl->version >> 16) & 0xff,
> >   		 ctrl->version & 0xffff);
> >   
> > -	pm_runtime_set_autosuspend_delay(dev, 3000);
> > -	pm_runtime_use_autosuspend(dev);
> > -	pm_runtime_mark_last_busy(dev);
> > -	pm_runtime_set_active(dev);
> > -	pm_runtime_enable(dev);
> > -
> >   	/* Clk stop is not supported on WSA Soundwire masters */
> >   	if (ctrl->version <= 0x01030000) {
> >   		ctrl->clock_stop_not_supported = true;