[PATCH] i2c: Move i2c request_irq so that it occurs after iop3xx_i2c_enable

[PATCH] i2c: Move i2c request_irq so that it occurs after iop3xx_i2c_enable

[Jon Ringle]

If there is a pending i2c interrupt present before i2c-iop3xx initialization
then it must be cleared first before registering irq handler. Otherwise,
a hung system due to an unhandled interrupt loop may occur.

Signed-off-by: Jon Ringle <jon@ringle.org>

---
 drivers/i2c/busses/i2c-iop3xx.c |   16 ++++++++--------
 1 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/i2c/busses/i2c-iop3xx.c b/drivers/i2c/busses/i2c-iop3xx.c
index a75c75e..e6dc46d 100644
--- a/drivers/i2c/busses/i2c-iop3xx.c
+++ b/drivers/i2c/busses/i2c-iop3xx.c
@@ -471,14 +471,6 @@ iop3xx_i2c_probe(struct platform_device *pdev)
 		ret = -ENXIO;
 		goto unmap;
 	}
-	ret = request_irq(irq, iop3xx_i2c_irq_handler, 0,
-				pdev->name, adapter_data);
-
-	if (ret) {
-		ret = -EIO;
-		goto unmap;
-	}
-
 	memcpy(new_adapter->name, pdev->name, strlen(pdev->name));
 	new_adapter->owner = THIS_MODULE;
 	new_adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
@@ -497,6 +489,14 @@ iop3xx_i2c_probe(struct platform_device *pdev)
 	iop3xx_i2c_reset(adapter_data);
 	iop3xx_i2c_enable(adapter_data);
 
+	ret = request_irq(irq, iop3xx_i2c_irq_handler, 0,
+				pdev->name, adapter_data);
+
+	if (ret) {
+		ret = -EIO;
+		goto unmap;
+	}
+
 	platform_set_drvdata(pdev, new_adapter);
 	new_adapter->algo_data = adapter_data;
 
-- 
tg: (74fca6a..) t/isc-31/i2c-request_irq-iop3xx_i2c_enable-reorder (depends on: b2.6.31.y)

Re: [PATCH] i2c: Move i2c request_irq so that it occurs after iop3xx_i2c_enable

[Jiri Kosina]

On Fri, 18 Sep 2009, Jon Ringle wrote:

> If there is a pending i2c interrupt present before i2c-iop3xx initialization
> then it must be cleared first before registering irq handler. Otherwise,
> a hung system due to an unhandled interrupt loop may occur.

Hi Jon,

this doesn't really qualify for trivial tree. I am adding Jean Delvare to 
CC.

> Signed-off-by: Jon Ringle <jon@ringle.org>
> 
> ---
>  drivers/i2c/busses/i2c-iop3xx.c |   16 ++++++++--------
>  1 files changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-iop3xx.c b/drivers/i2c/busses/i2c-iop3xx.c
> index a75c75e..e6dc46d 100644
> --- a/drivers/i2c/busses/i2c-iop3xx.c
> +++ b/drivers/i2c/busses/i2c-iop3xx.c
> @@ -471,14 +471,6 @@ iop3xx_i2c_probe(struct platform_device *pdev)
>  		ret = -ENXIO;
>  		goto unmap;
>  	}
> -	ret = request_irq(irq, iop3xx_i2c_irq_handler, 0,
> -				pdev->name, adapter_data);
> -
> -	if (ret) {
> -		ret = -EIO;
> -		goto unmap;
> -	}
> -
>  	memcpy(new_adapter->name, pdev->name, strlen(pdev->name));
>  	new_adapter->owner = THIS_MODULE;
>  	new_adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
> @@ -497,6 +489,14 @@ iop3xx_i2c_probe(struct platform_device *pdev)
>  	iop3xx_i2c_reset(adapter_data);
>  	iop3xx_i2c_enable(adapter_data);
>  
> +	ret = request_irq(irq, iop3xx_i2c_irq_handler, 0,
> +				pdev->name, adapter_data);
> +
> +	if (ret) {
> +		ret = -EIO;
> +		goto unmap;
> +	}
> +
>  	platform_set_drvdata(pdev, new_adapter);
>  	new_adapter->algo_data = adapter_data;
>  
> -- 
> tg: (74fca6a..) t/isc-31/i2c-request_irq-iop3xx_i2c_enable-reorder (depends on: b2.6.31.y)
> 

-- 
Jiri Kosina
SUSE Labs, Novell Inc.

Re: [PATCH] i2c: Move i2c request_irq so that it occurs after iop3xx_i2c_enable

[Ben Dooks]

On Fri, Sep 18, 2009 at 04:32:04PM +0200, Jiri Kosina wrote:
> On Fri, 18 Sep 2009, Jon Ringle wrote:
> 
> > If there is a pending i2c interrupt present before i2c-iop3xx initialization
> > then it must be cleared first before registering irq handler. Otherwise,
> > a hung system due to an unhandled interrupt loop may occur.
> 
> Hi Jon,
> 
> this doesn't really qualify for trivial tree. I am adding Jean Delvare to 
> CC.

I'm the correct one to add, will probably be doing a push over the weekend
so will add it to my i2c next tree.
 
> > Signed-off-by: Jon Ringle <jon@ringle.org>
> > 
> > ---
> >  drivers/i2c/busses/i2c-iop3xx.c |   16 ++++++++--------
> >  1 files changed, 8 insertions(+), 8 deletions(-)
> > 
> > diff --git a/drivers/i2c/busses/i2c-iop3xx.c b/drivers/i2c/busses/i2c-iop3xx.c
> > index a75c75e..e6dc46d 100644
> > --- a/drivers/i2c/busses/i2c-iop3xx.c
> > +++ b/drivers/i2c/busses/i2c-iop3xx.c
> > @@ -471,14 +471,6 @@ iop3xx_i2c_probe(struct platform_device *pdev)
> >  		ret = -ENXIO;
> >  		goto unmap;
> >  	}
> > -	ret = request_irq(irq, iop3xx_i2c_irq_handler, 0,
> > -				pdev->name, adapter_data);
> > -
> > -	if (ret) {
> > -		ret = -EIO;
> > -		goto unmap;
> > -	}
> > -
> >  	memcpy(new_adapter->name, pdev->name, strlen(pdev->name));
> >  	new_adapter->owner = THIS_MODULE;
> >  	new_adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
> > @@ -497,6 +489,14 @@ iop3xx_i2c_probe(struct platform_device *pdev)
> >  	iop3xx_i2c_reset(adapter_data);
> >  	iop3xx_i2c_enable(adapter_data);
> >  
> > +	ret = request_irq(irq, iop3xx_i2c_irq_handler, 0,
> > +				pdev->name, adapter_data);
> > +
> > +	if (ret) {
> > +		ret = -EIO;
> > +		goto unmap;
> > +	}
> > +
> >  	platform_set_drvdata(pdev, new_adapter);
> >  	new_adapter->algo_data = adapter_data;
> >  
> > -- 
> > tg: (74fca6a..) t/isc-31/i2c-request_irq-iop3xx_i2c_enable-reorder (depends on: b2.6.31.y)
> > 
> 
> -- 
> Jiri Kosina
> SUSE Labs, Novell Inc.

-- 
-- 
Ben

Q:      What's a light-year?
A:      One-third less calories than a regular year.