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Date: Sun, 03 Mar 2013 23:03:15 +0100
From: Daniel Mack <zonque@gmail.com>
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To: Peter Korsgaard <jacmet@sunsite.dk>
Subject: Re: [PATCH] mtd: devices: elm: check for device's presence before
 configuration
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Cc: dwmw2@infradead.org, linux-mtd@lists.infradead.org,
 Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
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On 03.03.2013 22:44, Peter Korsgaard wrote:
>>>>>> "Daniel" == Daniel Mack <zonque@gmail.com> writes:
> 
>  Daniel> In case the driver is not probed - due to config mismatches or errors
>  Daniel> in the DTS files - dev_get_drvdata() returns NULL, leading to an Ooops
>  Daniel> during boot. Better bail out with a warning in such cases.
> 
>  Daniel> Signed-off-by: Daniel Mack <zonque@gmail.com>
>  Daniel> Cc: Philip Avinash <avinashphilip@ti.com>
>  Daniel> Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
>  Daniel> ---
>  Daniel>  drivers/mtd/devices/elm.c | 5 +++++
>  Daniel>  1 file changed, 5 insertions(+)
> 
>  Daniel> diff --git a/drivers/mtd/devices/elm.c b/drivers/mtd/devices/elm.c
>  Daniel> index 2ec5da9..a9b6d04 100644
>  Daniel> --- a/drivers/mtd/devices/elm.c
>  Daniel> +++ b/drivers/mtd/devices/elm.c
>  Daniel> @@ -86,6 +86,11 @@ void elm_config(struct device *dev, enum bch_ecc bch_type)
>  Daniel>  	u32 reg_val;
>  Daniel>  	struct elm_info *info = dev_get_drvdata(dev);
>  
>  Daniel> +	if (!info) {
>  Daniel> +		dev_err(dev, "Unable to configure elm - device not probed?\n");
>  Daniel> +		return;
>  Daniel> +	}
>  Daniel> +
> 
> Even better would be to propagate the error message (E.G. return
> -ENODEV) and let omap2.c deal with it (fall back to sw).
> 

Yes, you're right. Will send an updated version later ...

Thanks,
Daniel