diff mbox

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

Message ID 1461675460-2295-6-git-send-email-jszhang@marvell.com (mailing list archive)
State New, archived
Headers show

Commit Message

Jisheng Zhang April 26, 2016, 12:57 p.m. UTC
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.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
---
 drivers/usb/host/xhci-plat.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

Comments

Felipe Balbi April 27, 2016, 5:33 a.m. UTC | #1
Jisheng Zhang <jszhang@marvell.com> 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.

Care to explain ?

> Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
> ---
>  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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Jisheng Zhang April 27, 2016, 6:33 a.m. UTC | #2
Dear Felipe,

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

> Jisheng Zhang <jszhang@marvell.com> 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@marvell.com>
> > ---
> >  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
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-usb" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html  
>
Felipe Balbi April 27, 2016, 7:19 a.m. UTC | #3
Hi,

Jisheng Zhang <jszhang@marvell.com> writes:
> Dear Felipe,
>
> On Wed, 27 Apr 2016 08:33:52 +0300 Felipe Balbi wrote:
>
>> Jisheng Zhang <jszhang@marvell.com> 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 ;)

oh okay, thanks for that. That's, IMHO, quite dangerous ;-)
diff mbox

Patch

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;