Re: [PATCH 6/7] slimbus: qcom-ngd-ctrl: Balance pm_runtime enablement for NGD

[Bjorn Andersson]

On Tue, Mar 10, 2026 at 01:30:25PM +0530, Mukesh Ojha wrote:
> On Mon, Mar 09, 2026 at 11:09:07PM -0500, Bjorn Andersson wrote:
> > The pm_runtime_enable() and pm_runtime_use_autosuspend() calls are
> > supposed to be balanced on exit, add these calls.
> > 
> > Fixes: 917809e2280b ("slimbus: ngd: Add qcom SLIMBus NGD driver")
> > Cc: stable@xxxxxxxxxxxxxxx
> > Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxxxx>
> > ---
> >  drivers/slimbus/qcom-ngd-ctrl.c | 6 +++++-
> >  1 file changed, 5 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c
> > index d932f7fd6170773890f561e3af444ac2c5730338..54a4c6ee1e71fe55794f09575979826d9aa5be9f 100644
> > --- a/drivers/slimbus/qcom-ngd-ctrl.c
> > +++ b/drivers/slimbus/qcom-ngd-ctrl.c
> > @@ -1584,8 +1584,11 @@ static int qcom_slim_ngd_probe(struct platform_device *pdev)
> >  	pm_runtime_enable(dev);
> >  	pm_runtime_get_noresume(dev);
> >  	ret = qcom_slim_ngd_qmi_svc_event_init(ctrl);
> > -	if (ret)
> > +	if (ret) {
> >  		dev_err(&pdev->dev, "QMI service registration failed:%d", ret);
> > +		pm_runtime_dont_use_autosuspend(dev);
> > +		pm_runtime_disable(dev);
> > +	}
> 
> Can this entire pm_runtime_* calls moved after
> qcom_slim_ngd_qmi_svc_event_init() ?
> 

As soon as qcom_slim_ngd_qmi_svc_event_init() executes we might get a
qcom_slim_ngd_qmi_new_server() if the service is already up which would
complete(qmi_up), which would unblock qcom_slim_ngd_up_worker() which
will invoke qcom_slim_ngd_enable() which currently operates
conditionally on pm_runtime_enabled().

So, what you're proposing does make some sense, but I think we should
try to clean that up in a subsequent series.

Regards,
Bjorn

> >  
> >  	return ret;
> >  }
> > @@ -1699,6 +1702,7 @@ static void qcom_slim_ngd_remove(struct platform_device *pdev)
> >  {
> >  	struct qcom_slim_ngd_ctrl *ctrl = platform_get_drvdata(pdev);
> >  
> > +	pm_runtime_dont_use_autosuspend(&pdev->dev);
> >  	pm_runtime_disable(&pdev->dev);
> >  	qcom_slim_ngd_enable(ctrl, false);
> >  	qcom_slim_ngd_exit_dma(ctrl);
> > 
> > -- 
> > 2.51.0
> > 
> 
> -- 
> -Mukesh Ojha