[PATCH] mxc_nand: fix PM

[PATCH] mxc_nand: fix PM

[Eric Bénard]

* when resuming, we get the following log :
nand_resume called for a chip which is not in suspended state
* this happens because mtd->suspend and mtd->resume are already
called from the mtd layer, thus they were called a second time
in mxc_nand so mtd complains when trying to resume for the
second time
* the fix is to remove these call and thus remove the supend and
resume functions of mxc_nand

Signed-off-by: Eric Bénard <eric@eukrea.com>
Cc: s.hauer@pengutronix.de
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mtd@lists.infradead.org
---
 drivers/mtd/nand/mxc_nand.c |   44 +------------------------------------------
 1 files changed, 1 insertions(+), 43 deletions(-)

diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c
index 314e2bf..217b247 100644
--- a/drivers/mtd/nand/mxc_nand.c
+++ b/drivers/mtd/nand/mxc_nand.c
@@ -892,53 +892,11 @@ static int __devexit mxcnd_remove(struct platform_device *pdev)
 	return 0;
 }
 
-#ifdef CONFIG_PM
-static int mxcnd_suspend(struct platform_device *pdev, pm_message_t state)
-{
-	struct mtd_info *mtd = platform_get_drvdata(pdev);
-	struct nand_chip *nand_chip = mtd->priv;
-	struct mxc_nand_host *host = nand_chip->priv;
-	int ret = 0;
-
-	DEBUG(MTD_DEBUG_LEVEL0, "MXC_ND : NAND suspend\n");
-
-	ret = mtd->suspend(mtd);
-
-	/*
-	 * nand_suspend locks the device for exclusive access, so
-	 * the clock must already be off.
-	 */
-	BUG_ON(!ret && host->clk_act);
-
-	return ret;
-}
-
-static int mxcnd_resume(struct platform_device *pdev)
-{
-	struct mtd_info *mtd = platform_get_drvdata(pdev);
-	struct nand_chip *nand_chip = mtd->priv;
-	struct mxc_nand_host *host = nand_chip->priv;
-	int ret = 0;
-
-	DEBUG(MTD_DEBUG_LEVEL0, "MXC_ND : NAND resume\n");
-
-	mtd->resume(mtd);
-
-	return ret;
-}
-
-#else
-# define mxcnd_suspend   NULL
-# define mxcnd_resume    NULL
-#endif				/* CONFIG_PM */
-
 static struct platform_driver mxcnd_driver = {
 	.driver = {
 		   .name = DRIVER_NAME,
-		   },
+	},
 	.remove = __devexit_p(mxcnd_remove),
-	.suspend = mxcnd_suspend,
-	.resume = mxcnd_resume,
 };
 
 static int __init mxc_nd_init(void)
-- 
1.6.3.3

Re: [PATCH] mxc_nand: fix PM

[Eric Bénard]

Hi Sascha,

Le 27/05/2010 19:55, Eric Bénard a écrit :
> * when resuming, we get the following log :
> nand_resume called for a chip which is not in suspended state
> * this happens because mtd->suspend and mtd->resume are already
> called from the mtd layer, thus they were called a second time
> in mxc_nand so mtd complains when trying to resume for the
> second time
> * the fix is to remove these call and thus remove the supend and
> resume functions of mxc_nand
>
any news concerning this patch ?

Eric

> Signed-off-by: Eric Bénard<eric@eukrea.com>
> Cc: s.hauer@pengutronix.de
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-mtd@lists.infradead.org
> ---
>   drivers/mtd/nand/mxc_nand.c |   44 +------------------------------------------
>   1 files changed, 1 insertions(+), 43 deletions(-)
>
> diff --git a/drivers/mtd/nand/mxc_nand.c b/drivers/mtd/nand/mxc_nand.c
> index 314e2bf..217b247 100644
> --- a/drivers/mtd/nand/mxc_nand.c
> +++ b/drivers/mtd/nand/mxc_nand.c
> @@ -892,53 +892,11 @@ static int __devexit mxcnd_remove(struct platform_device *pdev)
>   	return 0;
>   }
>
> -#ifdef CONFIG_PM
> -static int mxcnd_suspend(struct platform_device *pdev, pm_message_t state)
> -{
> -	struct mtd_info *mtd = platform_get_drvdata(pdev);
> -	struct nand_chip *nand_chip = mtd->priv;
> -	struct mxc_nand_host *host = nand_chip->priv;
> -	int ret = 0;
> -
> -	DEBUG(MTD_DEBUG_LEVEL0, "MXC_ND : NAND suspend\n");
> -
> -	ret = mtd->suspend(mtd);
> -
> -	/*
> -	 * nand_suspend locks the device for exclusive access, so
> -	 * the clock must already be off.
> -	 */
> -	BUG_ON(!ret&&  host->clk_act);
> -
> -	return ret;
> -}
> -
> -static int mxcnd_resume(struct platform_device *pdev)
> -{
> -	struct mtd_info *mtd = platform_get_drvdata(pdev);
> -	struct nand_chip *nand_chip = mtd->priv;
> -	struct mxc_nand_host *host = nand_chip->priv;
> -	int ret = 0;
> -
> -	DEBUG(MTD_DEBUG_LEVEL0, "MXC_ND : NAND resume\n");
> -
> -	mtd->resume(mtd);
> -
> -	return ret;
> -}
> -
> -#else
> -# define mxcnd_suspend   NULL
> -# define mxcnd_resume    NULL
> -#endif				/* CONFIG_PM */
> -
>   static struct platform_driver mxcnd_driver = {
>   	.driver = {
>   		   .name = DRIVER_NAME,
> -		   },
> +	},
>   	.remove = __devexit_p(mxcnd_remove),
> -	.suspend = mxcnd_suspend,
> -	.resume = mxcnd_resume,
>   };
>
>   static int __init mxc_nd_init(void)

Re: [PATCH] mxc_nand: fix PM

[Uwe Kleine-König]

Hello Eric,

On Thu, May 27, 2010 at 07:55:19PM +0200, Eric Bénard wrote:
> * when resuming, we get the following log :
> nand_resume called for a chip which is not in suspended state
> * this happens because mtd->suspend and mtd->resume are already
> called from the mtd layer, thus they were called a second time
> in mxc_nand so mtd complains when trying to resume for the
> second time
> * the fix is to remove these call and thus remove the supend and
> resume functions of mxc_nand
the commit log looks IMHO ugly.  Better make it (including Subject):

mtd/mxc_nand: don't call mtd->{suspend,resume} explicitly

The mtd layer is responsible to call mtd->{suspend,resume}.  Doing it
again in the driver is wrong and results in a warning:

	nand_resume called for a chip which is not in suspended state

at resume time.  Removing the calls from the resume and suspend
functions makes them empty allowing them to be deleted completely.

Signed-off-by: Eric Bénard <eric@eukrea.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mtd@lists.infradead.org

Best regards
Uwe

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

Re: [PATCH] mxc_nand: fix PM

[Artem Bityutskiy]

On Mon, 2010-06-14 at 09:07 +0200, Eric Bénard wrote:
> Hi Sascha,
> 
> Le 27/05/2010 19:55, Eric Bénard a écrit :
> > * when resuming, we get the following log :
> > nand_resume called for a chip which is not in suspended state
> > * this happens because mtd->suspend and mtd->resume are already
> > called from the mtd layer, thus they were called a second time
> > in mxc_nand so mtd complains when trying to resume for the
> > second time
> > * the fix is to remove these call and thus remove the supend and
> > resume functions of mxc_nand
> >
> any news concerning this patch ?
> 

Pushed to l2-mtd-2.6.git / dunno

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)

Re: [PATCH] mxc_nand: fix PM

[Artem Bityutskiy]

On Mon, 2010-06-14 at 09:07 +0200, Eric Bénard wrote:
> Hi Sascha,
> 
> Le 27/05/2010 19:55, Eric Bénard a écrit :
> > * when resuming, we get the following log :
> > nand_resume called for a chip which is not in suspended state
> > * this happens because mtd->suspend and mtd->resume are already
> > called from the mtd layer, thus they were called a second time
> > in mxc_nand so mtd complains when trying to resume for the
> > second time
> > * the fix is to remove these call and thus remove the supend and
> > resume functions of mxc_nand
> >
> any news concerning this patch ?

Pushed to l2-mtd-2.6.git / dunno

-- 
Best Regards,
Artem Bityutskiy (Артём Битюцкий)