Subject: Re: [PATCH v2 1/1] mux: mux-core: Add NULL check for dev->of_node
To: sathyanarayanan.kuppuswamy@linux.intel.com
Cc: linux-kernel@vger.kernel.org, sathyaosid@gmail.com
References: <c6f9c640d7617a7aefe865b747494e98a510f37a.1499463875.git.sathyanarayanan.kuppuswamy@linux.intel.com>
From: Peter Rosin <peda@axentia.se>
Organization: Axentia Technologies AB
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Date: Sat, 8 Jul 2017 23:00:39 +0200
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On 2017-07-07 23:46, sathyanarayanan.kuppuswamy@linux.intel.com wrote:
> From: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
> 
> If dev->of_node is NULL, then calling mux_control_get()
> function can lead to NULL pointer exception. So adding
> a NULL check for dev->of_node.
> 
> Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>

Do you have a driver that might call mux_control_get and not have any
of_node? If not, I don't see the point of this check.

Cheers,
peda

> ---
>  drivers/mux/mux-core.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> Changes since v1:
>  * Removed dummy new line.
> 
> diff --git a/drivers/mux/mux-core.c b/drivers/mux/mux-core.c
> index 90b8995..924c983 100644
> --- a/drivers/mux/mux-core.c
> +++ b/drivers/mux/mux-core.c
> @@ -438,6 +438,9 @@ struct mux_control *mux_control_get(struct device *dev, const char *mux_name)
>  	int index = 0;
>  	int ret;
>  
> +	if (!np)
> +		return ERR_PTR(-ENODEV);
> +
>  	if (mux_name) {
>  		index = of_property_match_string(np, "mux-control-names",
>  						 mux_name);
>