[PATCH 1/2] usb: ehci-exynos: Return immediately from suspend if ehci_suspend fails

[PATCH 1/2] usb: ehci-exynos: Return immediately from suspend if ehci_suspend fails

[Vivek Gautam]

Patch 'b8efdaf USB: EHCI: add check for wakeup/suspend race'
adds a check for possible race between suspend and wakeup interrupt,
and thereby it returns -EBUSY as error code if there's a wakeup
interrupt.
So the platform host controller should not proceed further with
its suspend callback, rather should return immediately to avoid
powering down the essential things, like phy.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Jingoo Han <jg1.han@samsung.com>
---

Based on 'usb-next' branch of Greg's usb tree.

 drivers/usb/host/ehci-exynos.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/ehci-exynos.c b/drivers/usb/host/ehci-exynos.c
index d1d8c47..a4550eb 100644
--- a/drivers/usb/host/ehci-exynos.c
+++ b/drivers/usb/host/ehci-exynos.c
@@ -212,6 +212,8 @@ static int exynos_ehci_suspend(struct device *dev)
 	int rc;
 
 	rc = ehci_suspend(hcd, do_wakeup);
+	if (rc)
+		return rc;
 
 	if (exynos_ehci->otg)
 		exynos_ehci->otg->set_host(exynos_ehci->otg, &hcd->self);
@@ -221,7 +223,7 @@ static int exynos_ehci_suspend(struct device *dev)
 
 	clk_disable_unprepare(exynos_ehci->clk);
 
-	return rc;
+	return 0;
 }
 
 static int exynos_ehci_resume(struct device *dev)
-- 
1.7.10.4

[PATCH 2/2] usb: ehci-platform: Return immediately from suspend if ehci_suspend fails

[Vivek Gautam]

Patch 'b8efdaf USB: EHCI: add check for wakeup/suspend race'
adds a check for possible race between suspend and wakeup interrupt,
and thereby it returns -EBUSY as error code if there's a wakeup
interrupt.
So the platform host controller should not proceed further with
its suspend callback, rather should return immediately to avoid
powering down the essential things, like phy.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: Hans de Goede <hdegoede@redhat.com>
---

Based on 'usb-next' branch of Greg's usb tree.

 drivers/usb/host/ehci-platform.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/ehci-platform.c b/drivers/usb/host/ehci-platform.c
index b3a0e11..60d3d1a 100644
--- a/drivers/usb/host/ehci-platform.c
+++ b/drivers/usb/host/ehci-platform.c
@@ -303,11 +303,13 @@ static int ehci_platform_suspend(struct device *dev)
 	int ret;
 
 	ret = ehci_suspend(hcd, do_wakeup);
+	if (ret)
+		return ret;
 
 	if (pdata->power_suspend)
 		pdata->power_suspend(pdev);
 
-	return ret;
+	return 0;
 }
 
 static int ehci_platform_resume(struct device *dev)
-- 
1.7.10.4

Re: [PATCH 1/2] usb: ehci-exynos: Return immediately from suspend if ehci_suspend fails

[Jingoo Han]

On Wednesday, April 09, 2014 1:01 PM, Vivek Gautam wrote:
> 
> Patch 'b8efdaf USB: EHCI: add check for wakeup/suspend race'
> adds a check for possible race between suspend and wakeup interrupt,
> and thereby it returns -EBUSY as error code if there's a wakeup
> interrupt.
> So the platform host controller should not proceed further with
> its suspend callback, rather should return immediately to avoid
> powering down the essential things, like phy.
> 
> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
> Cc: Alan Stern <stern@rowland.harvard.edu>
> Cc: Jingoo Han <jg1.han@samsung.com>

Acked-by: Jingoo Han <jg1.han@samsung.com>

Best regards,
Jingoo Han

> ---
> 
> Based on 'usb-next' branch of Greg's usb tree.
> 
>  drivers/usb/host/ehci-exynos.c |    4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/host/ehci-exynos.c b/drivers/usb/host/ehci-exynos.c
> index d1d8c47..a4550eb 100644
> --- a/drivers/usb/host/ehci-exynos.c
> +++ b/drivers/usb/host/ehci-exynos.c
> @@ -212,6 +212,8 @@ static int exynos_ehci_suspend(struct device *dev)
>  	int rc;
> 
>  	rc = ehci_suspend(hcd, do_wakeup);
> +	if (rc)
> +		return rc;
> 
>  	if (exynos_ehci->otg)
>  		exynos_ehci->otg->set_host(exynos_ehci->otg, &hcd->self);
> @@ -221,7 +223,7 @@ static int exynos_ehci_suspend(struct device *dev)
> 
>  	clk_disable_unprepare(exynos_ehci->clk);
> 
> -	return rc;
> +	return 0;
>  }
> 
>  static int exynos_ehci_resume(struct device *dev)
> --
> 1.7.10.4

Re: [PATCH 1/2] usb: ehci-exynos: Return immediately from suspend if ehci_suspend fails

[Alan Stern]

On Wed, 9 Apr 2014, Vivek Gautam wrote:

> Patch 'b8efdaf USB: EHCI: add check for wakeup/suspend race'
> adds a check for possible race between suspend and wakeup interrupt,
> and thereby it returns -EBUSY as error code if there's a wakeup
> interrupt.
> So the platform host controller should not proceed further with
> its suspend callback, rather should return immediately to avoid
> powering down the essential things, like phy.
> 
> Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
> Cc: Alan Stern <stern@rowland.harvard.edu>
> Cc: Jingoo Han <jg1.han@samsung.com>
> ---
> 
> Based on 'usb-next' branch of Greg's usb tree.
> 
>  drivers/usb/host/ehci-exynos.c |    4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/host/ehci-exynos.c b/drivers/usb/host/ehci-exynos.c
> index d1d8c47..a4550eb 100644
> --- a/drivers/usb/host/ehci-exynos.c
> +++ b/drivers/usb/host/ehci-exynos.c
> @@ -212,6 +212,8 @@ static int exynos_ehci_suspend(struct device *dev)
>  	int rc;
>  
>  	rc = ehci_suspend(hcd, do_wakeup);
> +	if (rc)
> +		return rc;
>  
>  	if (exynos_ehci->otg)
>  		exynos_ehci->otg->set_host(exynos_ehci->otg, &hcd->self);
> @@ -221,7 +223,7 @@ static int exynos_ehci_suspend(struct device *dev)
>  
>  	clk_disable_unprepare(exynos_ehci->clk);
>  
> -	return rc;
> +	return 0;
>  }
>  
>  static int exynos_ehci_resume(struct device *dev)

The first hunk of this patch is correct, but the second hunk isn't 
needed.  A similar remark is true for the ehci-platform patch.

Alan Stern

Re: [PATCH 1/2] usb: ehci-exynos: Return immediately from suspend if ehci_suspend fails

[Jingoo Han]

On Thursday, April 10, 2014 3:32 AM, Alan Stern wrote:
> On Wed, 9 Apr 2014, Vivek Gautam wrote:
> 
> > Patch 'b8efdaf USB: EHCI: add check for wakeup/suspend race'
> > adds a check for possible race between suspend and wakeup interrupt,
> > and thereby it returns -EBUSY as error code if there's a wakeup
> > interrupt.
> > So the platform host controller should not proceed further with
> > its suspend callback, rather should return immediately to avoid
> > powering down the essential things, like phy.
> >
> > Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
> > Cc: Alan Stern <stern@rowland.harvard.edu>
> > Cc: Jingoo Han <jg1.han@samsung.com>
> > ---
> >
> > Based on 'usb-next' branch of Greg's usb tree.
> >
> >  drivers/usb/host/ehci-exynos.c |    4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/usb/host/ehci-exynos.c b/drivers/usb/host/ehci-exynos.c
> > index d1d8c47..a4550eb 100644
> > --- a/drivers/usb/host/ehci-exynos.c
> > +++ b/drivers/usb/host/ehci-exynos.c
> > @@ -212,6 +212,8 @@ static int exynos_ehci_suspend(struct device *dev)
> >  	int rc;
> >
> >  	rc = ehci_suspend(hcd, do_wakeup);
> > +	if (rc)
> > +		return rc;
> >
> >  	if (exynos_ehci->otg)
> >  		exynos_ehci->otg->set_host(exynos_ehci->otg, &hcd->self);
> > @@ -221,7 +223,7 @@ static int exynos_ehci_suspend(struct device *dev)
> >
> >  	clk_disable_unprepare(exynos_ehci->clk);
> >
> > -	return rc;
> > +	return 0;
> >  }
> >
> >  static int exynos_ehci_resume(struct device *dev)
> 
> The first hunk of this patch is correct, but the second hunk isn't
> needed.  A similar remark is true for the ehci-platform patch.

Hi Alan,

Do you mean the following?

1st hunk
 +	if (rc)
 +		return rc;

2nd hunk
 -	return rc;
 +	return 0;

Currently, the 'rc' will be always 'zero'; however, I don't
Have any objection, because the code might be  modified later.

Best regards,
Jingoo Han
> 
> Alan Stern

Re: [PATCH 1/2] usb: ehci-exynos: Return immediately from suspend if ehci_suspend fails

[Alan Stern]

On Thu, 10 Apr 2014, Jingoo Han wrote:

> > > --- a/drivers/usb/host/ehci-exynos.c
> > > +++ b/drivers/usb/host/ehci-exynos.c
> > > @@ -212,6 +212,8 @@ static int exynos_ehci_suspend(struct device *dev)
> > >  	int rc;
> > >
> > >  	rc = ehci_suspend(hcd, do_wakeup);
> > > +	if (rc)
> > > +		return rc;
> > >
> > >  	if (exynos_ehci->otg)
> > >  		exynos_ehci->otg->set_host(exynos_ehci->otg, &hcd->self);
> > > @@ -221,7 +223,7 @@ static int exynos_ehci_suspend(struct device *dev)
> > >
> > >  	clk_disable_unprepare(exynos_ehci->clk);
> > >
> > > -	return rc;
> > > +	return 0;
> > >  }
> > >
> > >  static int exynos_ehci_resume(struct device *dev)
> > 
> > The first hunk of this patch is correct, but the second hunk isn't
> > needed.  A similar remark is true for the ehci-platform patch.
> 
> Hi Alan,
> 
> Do you mean the following?
> 
> 1st hunk
>  +	if (rc)
>  +		return rc;
> 
> 2nd hunk
>  -	return rc;
>  +	return 0;

Yes, that's what I mean.

> Currently, the 'rc' will be always 'zero'; however, I don't
> Have any objection, because the code might be  modified later.

Exactly.  We should add the new "if" statement but leave the "return 
rc" the way it is.

Alan Stern

Re: [PATCH 1/2] usb: ehci-exynos: Return immediately from suspend if ehci_suspend fails

[Vivek Gautam]

Hi Alan,


On Thu, Apr 10, 2014 at 7:06 AM, Alan Stern <stern@rowland.harvard.edu> wrote:
> On Thu, 10 Apr 2014, Jingoo Han wrote:
>
>> > > --- a/drivers/usb/host/ehci-exynos.c
>> > > +++ b/drivers/usb/host/ehci-exynos.c
>> > > @@ -212,6 +212,8 @@ static int exynos_ehci_suspend(struct device *dev)
>> > >   int rc;
>> > >
>> > >   rc = ehci_suspend(hcd, do_wakeup);
>> > > + if (rc)
>> > > +         return rc;
>> > >
>> > >   if (exynos_ehci->otg)
>> > >           exynos_ehci->otg->set_host(exynos_ehci->otg, &hcd->self);
>> > > @@ -221,7 +223,7 @@ static int exynos_ehci_suspend(struct device *dev)
>> > >
>> > >   clk_disable_unprepare(exynos_ehci->clk);
>> > >
>> > > - return rc;
>> > > + return 0;
>> > >  }
>> > >
>> > >  static int exynos_ehci_resume(struct device *dev)
>> >
>> > The first hunk of this patch is correct, but the second hunk isn't
>> > needed.  A similar remark is true for the ehci-platform patch.
>>
>> Hi Alan,
>>
>> Do you mean the following?
>>
>> 1st hunk
>>  +    if (rc)
>>  +            return rc;
>>
>> 2nd hunk
>>  -    return rc;
>>  +    return 0;
>
> Yes, that's what I mean.
>
>> Currently, the 'rc' will be always 'zero'; however, I don't
>> Have any objection, because the code might be  modified later.
>
> Exactly.  We should add the new "if" statement but leave the "return
> rc" the way it is.

Sure, i will update both the patches.

>
> Alan Stern
>
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