Re: [PATCH V2 1/2] mmc: sdhci-msm: Add interconnect bandwidth scaling support

[Sibi Sankar]

On 2020-06-04 22:39, Matthias Kaehlcke wrote:
> On Thu, Jun 04, 2020 at 04:44:42PM +0530, Pradeep P V K wrote:
> > Interconnect bandwidth scaling support is now added as a
> > part of OPP [1]. So, make sure interconnect driver is ready
> > before handling interconnect scaling.
> >
> > This change is based on
> > [1] [Patch v8] Introduce OPP bandwidth bindings
> > (https://lkml.org/lkml/2020/5/12/493)
> >
> > [2] [Patch v3] mmc: sdhci-msm: Fix error handling
> > for dev_pm_opp_of_add_table()
> > (https://lkml.org/lkml/2020/5/5/491)
> >
> > Signed-off-by: Pradeep P V K <ppvk@xxxxxxxxxxxxxx>
> > ---
> >  drivers/mmc/host/sdhci-msm.c | 13 +++++++++++++
> >  1 file changed, 13 insertions(+)
> >
> > diff --git a/drivers/mmc/host/sdhci-msm.c 
> > b/drivers/mmc/host/sdhci-msm.c
> > index b277dd7..a13ff1b 100644
> > --- a/drivers/mmc/host/sdhci-msm.c
> > +++ b/drivers/mmc/host/sdhci-msm.c
> > @@ -14,6 +14,7 @@
> >  #include <linux/slab.h>
> >  #include <linux/iopoll.h>
> >  #include <linux/regulator/consumer.h>
> > +#include <linux/interconnect.h>
> >
> >  #include "sdhci-pltfm.h"
> >  #include "cqhci.h"
> > @@ -2070,6 +2071,18 @@ static int sdhci_msm_probe(struct 
> > platform_device *pdev)
> >  	}
> >  	msm_host->bulk_clks[0].clk = clk;
> >
> > +	/* Make sure that ICC driver is ready for interconnect bandwdith
> > +	 * scaling before registering the device for OPP.
> > +	 */
> > +	ret = dev_pm_opp_of_find_icc_paths(&pdev->dev, NULL);
> > +	if (ret) {
> > +		if (ret == -EPROBE_DEFER)
> > +			dev_info(&pdev->dev, "defer icc path: %d\n", ret);
>
> I already commented on this on v1:
>
>   This log seems to add little more than noise, or are there particular 
> reasons
>   why it is useful in this driver? Most drivers just return silently in 
> case of
>   deferred probing.
>
> If you think the log is really needed please explain why.

Both the err logs seem redundant.
EPROBE_DEFERS are rather readily
noticeable through the return val.
dev_.._find_icc_paths already prints
err messages when we fail to get icc
paths.


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