Re: [RESEND PATCH v2 5/7] usb: xhci: plat: Remove checks for optional clock in error/remove path

From: Jisheng Zhang
Date: Wed Apr 27 2016 - 02:38:10 EST


Dear Felipe,

On Wed, 27 Apr 2016 08:33:52 +0300 Felipe Balbi wrote:

> Jisheng Zhang <jszhang@xxxxxxxxxxx> writes:
> > Commit 63589e92c2d9 ("clk: Ignore error and NULL pointers passed to
> > clk_{unprepare, disable}()") allows NULL or error pointer to be passed
> > unconditionally.
> >
> > This patch is to simplify probe error and remove code paths.
>
> this seems wrong to me. xhci->clk isn't initialized to NULL, it's either
> initialized to a valid struct clk * or some ERR_PTR() value.

Commit 63589e92c2d9 could also ignore error value ;)

>
> Care to explain ?
>
> > Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
> > ---
> > drivers/usb/host/xhci-plat.c | 6 ++----
> > 1 file changed, 2 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> > index 0e69712..83669d0 100644
> > --- a/drivers/usb/host/xhci-plat.c
> > +++ b/drivers/usb/host/xhci-plat.c
> > @@ -266,8 +266,7 @@ put_usb3_hcd:
> > usb_put_hcd(xhci->shared_hcd);
> >
> > disable_clk:
> > - if (!IS_ERR(clk))
> > - clk_disable_unprepare(clk);
> > + clk_disable_unprepare(clk);
> >
> > put_hcd:
> > usb_put_hcd(hcd);
> > @@ -287,8 +286,7 @@ static int xhci_plat_remove(struct platform_device *dev)
> > usb_remove_hcd(hcd);
> > usb_put_hcd(xhci->shared_hcd);
> >
> > - if (!IS_ERR(clk))
> > - clk_disable_unprepare(clk);
> > + clk_disable_unprepare(clk);
> > usb_put_hcd(hcd);
> >
> > return 0;
> > --
> > 2.8.1
> >
> > --
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