RE: [RESEND v2 4/5] PCI: imx6: Fix the clock reference handling unbalance when link never came up

[Richard Zhu]

> -----Original Message-----
> From: Krzysztof Wilczyński <kw@xxxxxxxxx>
> Sent: Saturday, October 23, 2021 5:54 PM
> To: Richard Zhu <hongxing.zhu@xxxxxxx>
> Cc: Bjorn Helgaas <helgaas@xxxxxxxxxx>; l.stach@xxxxxxxxxxxxxx;
> bhelgaas@xxxxxxxxxx; lorenzo.pieralisi@xxxxxxx; linux-pci@xxxxxxxxxxxxxxx;
> dl-linux-imx <linux-imx@xxxxxxx>; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx
> Subject: Re: [RESEND v2 4/5] PCI: imx6: Fix the clock reference handling
> unbalance when link never came up
> 
> Hi,
> 
> [...]
> > > > > > -	default:
> > > > > > -		break;
> > > >
> > > > While you're at it, this "default: break;" thing is pointless.
> > > > Normally it's better to just *move* something without changing it
> > > > at all, but this is such a simple thing I think you could drop
> > > > this at the same time as the move.
> > > >
> > > [Richard Zhu] Okay, got that. Would remove the "default:break" later.
> Thanks.
> > [Richard Zhu] I figure out that the default:break is required by
> IMX6Q/IMX6QP.
> >  So I just don't drop them in v3 patch-set.
> 
> I hope you don't mind me asking, but how is an empty default case in the
> switch statement helping IMX6Q and IMX6QP?  What does it achieve for
> these two controllers specifically?
> 
[Richard Zhu] Never mind. 😊.
There might be following building warning if the "default:break" is removed.
"  CC      drivers/pci/controller/dwc/pci-imx6.o
drivers/pci/controller/dwc/pci-imx6.c: In function ‘imx6_pcie_clk_disable’:
drivers/pci/controller/dwc/pci-imx6.c:527:2: warning: enumeration value ‘IMX6Q’ not handled in switch [-Wswitch]
  527 |  switch (imx6_pcie->drvdata->variant) {
      |  ^~~~~~
drivers/pci/controller/dwc/pci-imx6.c:527:2: warning: enumeration value ‘IMX6QP’ not handled in switch [-Wswitch]"

Best Regards
Richard Zhu

> 	Krzysztof