Re: [PATCH 2/2] PCI: rockchip: Simplify optional regulator handling

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon, Nov 18, 2019 at 12:20:10PM +0000, Robin Murphy wrote:
> On 18/11/2019 11:59 am, Mark Brown wrote:
> > On Sat, Nov 16, 2019 at 12:54:20PM +0000, Robin Murphy wrote:
> > > Null checks are both cheaper and more readable than having !IS_ERR()
> > > splattered everywhere.
> > 
> > > -	if (IS_ERR(rockchip->vpcie3v3))
> > > +	if (!rockchip->vpcie3v3)
> > >   		return;
> > >   	/*
> > > @@ -611,6 +611,7 @@ static int rockchip_pcie_parse_host_dt(struct rockchip_pcie *rockchip)
> > >   		if (PTR_ERR(rockchip->vpcie12v) != -ENODEV)
> > >   			return PTR_ERR(rockchip->vpcie12v);
> > >   		dev_info(dev, "no vpcie12v regulator found\n");
> > > +		rockchip->vpcie12v = NULL;
> > 
> > According to the API NULL is a valid regulator.  We don't currently
> > actually do this but it's storing up surprises if you treat it as
> > invalid.
> 
> Ah, OK - I'd assumed NULL wasn't valid based on regulator_enable()
> immediately dereferencing its argument without any checks. If we'd rather
> not bake in that assumption then this patch can happily be ignored.

I'd suggest we drop this patch.

"IS_ERR(ptr)" is not the same as "!ptr", for values of ptr between 0 and
-4095 inclusive.

Regardless the effect of this patch with the regulator framework, I don't
think we want to create an example that others may follow.

Thanks,

Andrew Murray

> 
> Thanks,
> Robin.



[Index of Archives]     [DMA Engine]     [Linux Coverity]     [Linux USB]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Greybus]

  Powered by Linux