Re: [PATCH] ASoC: amd: ps: Fix uninitialized ret in create_acp64_platform_devs()

[Nathan Chancellor <nathan@kernel.org>]

On Thu, Jan 05, 2023 at 10:11:09AM -0700, Nathan Chancellor wrote:
> On Thu, Jan 05, 2023 at 10:34:10PM +0530, Mukunda,Vijendar wrote:
> > On 05/01/23 21:23, Nathan Chancellor wrote:
> > > Clang warns:
> > >
> > >   sound/soc/amd/ps/pci-ps.c:218:2: error: variable 'ret' is used uninitialized whenever switch default is taken [-Werror,-Wsometimes-uninitialized]
> > >           default:
> > >           ^~~~~~~
> > >   sound/soc/amd/ps/pci-ps.c:239:9: note: uninitialized use occurs here
> > >           return ret;
> > >                  ^~~
> > >   sound/soc/amd/ps/pci-ps.c:190:9: note: initialize the variable 'ret' to silence this warning
> > >           int ret;
> > >                  ^
> > >                   = 0
> > >   1 error generated.
> > >
> > > Return -ENODEV, which matches the debug message's description of this block.
> > >
> > > Fixes: 1d325cdaf7a2 ("ASoC: amd: ps: refactor platform device creation logic")
> > > Link: https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2FClangBuiltLinux%2Flinux%2Fissues%2F1779&data=05%7C01%7CVijendar.Mukunda%40amd.com%7Cad26656c3d2f4c75d00208daef350528%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C638085308267581104%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=eeHVStOIOcy%2FdDISOKlGNeyEwx4i5AtJZmQ5dcNB7XQ%3D&reserved=0
> > > Signed-off-by: Nathan Chancellor <nathan@kernel.org>
> > > ---
> > >  sound/soc/amd/ps/pci-ps.c | 1 +
> > >  1 file changed, 1 insertion(+)
> > >
> > > diff --git a/sound/soc/amd/ps/pci-ps.c b/sound/soc/amd/ps/pci-ps.c
> > > index 401cfd0036be..f54b9fd9c3ce 100644
> > > --- a/sound/soc/amd/ps/pci-ps.c
> > > +++ b/sound/soc/amd/ps/pci-ps.c
> > > @@ -217,6 +217,7 @@ static int create_acp63_platform_devs(struct pci_dev *pci, struct acp63_dev_data
> > >  		break;
> > >  	default:
> > >  		dev_dbg(&pci->dev, "No PDM devices found\n");
> > > +		ret = -ENODEV;
> > ACP PCI driver supports different configurations. As per design , even  when no child dev
> > nodes are created , ACP driver probe should be successful. ACP PCI driver probe failure
> > causes power state transition failures when no child device nodes are created.
> > We should not return -ENODEV in this case.
> > return 0 is enough in this case. No need to de-init the ACP.
> 
> Thank you for the review and input and sorry for getting it wrong! I
> will send a v2 replacing 'break;' with 'return 0;' shortly.

Actually, I re-read your message and looked at the code now that I am
back in front of my keyboard and I am a little confused by your message.
Should 'goto de_init' be replaced with 'return 0' to avoid the call to
acp63_deinit() or should ret just be initialized to 0 in this block so
that the call to acp63_deinit() still happens?

Thanks again for your input!
Nathan

> > >  		goto de_init;
> > >  	}
> > >  
> > >
> > > ---
> > > base-commit: 03178b4f7e2c59ead102e5ab5acb82ce1eaefe46
> > > change-id: 20230105-wsometimes-uninitialized-pci-ps-c-3b5725c6ed31
> > >
> > > Best regards,
> > 
>