[PATCH] imxfb: correct location of callbacks in suspend and resume

[PATCH] imxfb: correct location of callbacks in suspend and resume

[Uwe Kleine-König]

The probe function passes a pointer to a struct fb_info to
platform_set_drvdata, so don't interpret the return value of
platform_get_drvdata as a pointer to struct imxfb_info.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Sascha Hauer <kernel@pengutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
---
 drivers/video/imxfb.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
index 66358fa..b4b6dec 100644
--- a/drivers/video/imxfb.c
+++ b/drivers/video/imxfb.c
@@ -593,7 +593,8 @@ static int imxfb_activate_var(struct fb_var_screeninfo *var, struct fb_info *inf
  */
 static int imxfb_suspend(struct platform_device *dev, pm_message_t state)
 {
-	struct imxfb_info *fbi = platform_get_drvdata(dev);
+	struct fb_info *info = platform_get_drvdata(dev);
+	struct imxfb_info *fbi = info->par;
 
 	pr_debug("%s\n", __func__);
 
@@ -603,7 +604,8 @@ static int imxfb_suspend(struct platform_device *dev, pm_message_t state)
 
 static int imxfb_resume(struct platform_device *dev)
 {
-	struct imxfb_info *fbi = platform_get_drvdata(dev);
+	struct fb_info *info = platform_get_drvdata(dev);
+	struct imxfb_info *fbi = info->par;
 
 	pr_debug("%s\n", __func__);
 
-- 
1.6.6

Re: [PATCH] imxfb: correct location of callbacks in suspend and resume

[Andrew Morton]

On Mon, 25 Jan 2010 16:37:34 +0100
Uwe Kleine-K__nig  <u.kleine-koenig@pengutronix.de> wrote:

> The probe function passes a pointer to a struct fb_info to
> platform_set_drvdata, so don't interpret the return value of
> platform_get_drvdata as a pointer to struct imxfb_info.
> 
> Signed-off-by: Uwe Kleine-K__nig <u.kleine-koenig@pengutronix.de>
> Acked-by: Sascha Hauer <kernel@pengutronix.de>
> Cc: linux-arm-kernel@lists.infradead.org
> ---
>  drivers/video/imxfb.c |    6 ++++--
>  1 files changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
> index 66358fa..b4b6dec 100644
> --- a/drivers/video/imxfb.c
> +++ b/drivers/video/imxfb.c
> @@ -593,7 +593,8 @@ static int imxfb_activate_var(struct fb_var_screeninfo *var, struct fb_info *inf
>   */
>  static int imxfb_suspend(struct platform_device *dev, pm_message_t state)
>  {
> -	struct imxfb_info *fbi = platform_get_drvdata(dev);
> +	struct fb_info *info = platform_get_drvdata(dev);
> +	struct imxfb_info *fbi = info->par;
>  
>  	pr_debug("%s\n", __func__);
>  
> @@ -603,7 +604,8 @@ static int imxfb_suspend(struct platform_device *dev, pm_message_t state)
>  
>  static int imxfb_resume(struct platform_device *dev)
>  {
> -	struct imxfb_info *fbi = platform_get_drvdata(dev);
> +	struct fb_info *info = platform_get_drvdata(dev);
> +	struct imxfb_info *fbi = info->par;
>  
>  	pr_debug("%s\n", __func__);
>  

What were the runtime effects of this bug?

Re: [PATCH] imxfb: correct location of callbacks in suspend and resume

[Uwe Kleine-König]

Hello,

On Wed, Jan 27, 2010 at 03:48:18PM -0800, Andrew Morton wrote:
> On Mon, 25 Jan 2010 16:37:34 +0100
> Uwe Kleine-K__nig  <u.kleine-koenig@pengutronix.de> wrote:
> 
> > The probe function passes a pointer to a struct fb_info to
> > platform_set_drvdata, so don't interpret the return value of
> > platform_get_drvdata as a pointer to struct imxfb_info.
> > 
> > Signed-off-by: Uwe Kleine-K__nig <u.kleine-koenig@pengutronix.de>
> > Acked-by: Sascha Hauer <kernel@pengutronix.de>
> > Cc: linux-arm-kernel@lists.infradead.org
> > ---
> >  drivers/video/imxfb.c |    6 ++++--
> >  1 files changed, 4 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/video/imxfb.c b/drivers/video/imxfb.c
> > index 66358fa..b4b6dec 100644
> > --- a/drivers/video/imxfb.c
> > +++ b/drivers/video/imxfb.c
> > @@ -593,7 +593,8 @@ static int imxfb_activate_var(struct fb_var_screeninfo *var, struct fb_info *inf
> >   */
> >  static int imxfb_suspend(struct platform_device *dev, pm_message_t state)
> >  {
> > -	struct imxfb_info *fbi = platform_get_drvdata(dev);
> > +	struct fb_info *info = platform_get_drvdata(dev);
> > +	struct imxfb_info *fbi = info->par;
> >  
> >  	pr_debug("%s\n", __func__);
> >  
> > @@ -603,7 +604,8 @@ static int imxfb_suspend(struct platform_device *dev, pm_message_t state)
> >  
> >  static int imxfb_resume(struct platform_device *dev)
> >  {
> > -	struct imxfb_info *fbi = platform_get_drvdata(dev);
> > +	struct fb_info *info = platform_get_drvdata(dev);
> > +	struct imxfb_info *fbi = info->par;
> >  
> >  	pr_debug("%s\n", __func__);
> >  
> 
> What were the runtime effects of this bug?
For me it was that in the original imxfb_info *fbi backlight_power was
NULL but in imxfb_suspend it was 4 resulting in an oops as imxfb_suspend
calls imxfb_disable_controller(fbi) which in turn has

	if (fbi->backlight_power)
		fbi->backlight_power(0);

.

Best regards
Uwe

-- 
Pengutronix e.K.                              | Uwe Kleine-König            |
Industrial Linux Solutions                    | http://www.pengutronix.de/  |

Re: [PATCH] imxfb: correct location of callbacks in suspend and resume

[Andrew Morton]

On Thu, 28 Jan 2010 08:41:01 +0100 Uwe Kleine-K__nig <u.kleine-koenig@pengutronix.de> wrote:

> > What were the runtime effects of this bug?
> For me it was that in the original imxfb_info *fbi backlight_power was
> NULL but in imxfb_suspend it was 4 resulting in an oops as imxfb_suspend
> calls imxfb_disable_controller(fbi) which in turn has
> 
> 	if (fbi->backlight_power)
> 		fbi->backlight_power(0);

OK, thanks, that was important info.

I rescheduled the patch for 2.6.33 and marked it for 2.6.32.x backporting.