Re: [PATCH] usb: gadget: m66592-udc: Add check for clk_enable()

[Greg KH <gregkh@linuxfoundation.org>]

On Tue, Dec 17, 2024 at 10:06:26PM -0500, Mingwei Zheng wrote:
> Hi Greg,
> 
> On Mon, Dec 16, 2024 at 2:56 AM Greg KH <gregkh@linuxfoundation.org> wrote:
> >
> > On Sun, Dec 15, 2024 at 03:53:58PM -0500, Mingwei Zheng wrote:
> > > Add check for the return value of clk_enable() to catch the potential
> > > error.
> > >
> > > Fixes: b4822e2317e8 ("usb: gadget: m66592-udc: Convert to use module_platform_driver()")
> > > Signed-off-by: Mingwei Zheng <zmw12306@gmail.com>
> > > Signed-off-by: Jiasheng Jiang <jiashengjiangcool@gmail.com>
> >
> > Why this order of signed-off-by lines?  Shouldn't yours be last?  Who
> > wrote this patch?
> >
> 
> I listed two names because both of us co-authored this patch.
> 
> > > ---
> > >  drivers/usb/gadget/udc/m66592-udc.c | 6 +++++-
> > >  1 file changed, 5 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/usb/gadget/udc/m66592-udc.c b/drivers/usb/gadget/udc/m66592-udc.c
> > > index a938b2af0944..bf408476a24c 100644
> > > --- a/drivers/usb/gadget/udc/m66592-udc.c
> > > +++ b/drivers/usb/gadget/udc/m66592-udc.c
> > > @@ -1606,7 +1606,11 @@ static int m66592_probe(struct platform_device *pdev)
> > >                       ret = PTR_ERR(m66592->clk);
> > >                       goto clean_up2;
> > >               }
> > > -             clk_enable(m66592->clk);
> > > +             ret = clk_enable(m66592->clk);
> > > +             if (ret) {
> > > +                     clk_put(m66592->clk);
> > > +                     goto clean_up2;
> > > +             }
> >
> > How did you find this and how was it tested?
> >
> > thanks,
> >
> > greg k-h
> 
> We found it through a static analysis tool.

Then you need to properly document that as our documentation says it is
required, right?

thanks,

greg k-h