Date: Tue, 27 Jun 2017 17:28:31 +0100
From: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
To: Gaurav Gupta <gauragup@cisco.com>
CC: <lgirdwood@gmail.com>, <broonie@kernel.org>,
        <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] regulator: core: Lookup based on supply name alone as
 last option
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On Mon, Jun 26, 2017 at 10:57:12PM -0700, Gaurav Gupta wrote:
> If there are two regulators with the same supply name, the current
> lookup just based on the supply name would always return the first one.
> Further in the function, there is code to check both dev name and supply
> name and return the matching regulator. This should be done before the
> lookup based on supply name alone, which should be a last resort.
> 
> Signed-off-by: Gaurav Gupta <gauragup@cisco.com>
> ---

A patch has already been merged to do this:

https://lkml.org/lkml/2017/6/13/852

Thanks,
Charles

>  drivers/regulator/core.c | 5 +----
>  1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
> index c0d9ae8..80460df 100644
> --- a/drivers/regulator/core.c
> +++ b/drivers/regulator/core.c
> @@ -1489,10 +1489,6 @@ static struct regulator_dev *regulator_dev_lookup(struct device *dev,
>  	if (dev)
>  		devname = dev_name(dev);
>  
> -	r = regulator_lookup_by_name(supply);
> -	if (r)
> -		return r;
> -
>  	mutex_lock(&regulator_list_mutex);
>  	list_for_each_entry(map, &regulator_map_list, list) {
>  		/* If the mapping has a device set up it must match */
> @@ -1508,6 +1504,7 @@ static struct regulator_dev *regulator_dev_lookup(struct device *dev,
>  	}
>  	mutex_unlock(&regulator_list_mutex);
>  
> +	r = regulator_lookup_by_name(supply);

Also the loop above doesn't return it simply sets r so this would
overwrite the discovered regulator with the lookup based on
supply name alone.

>  	if (r)
>  		return r;
>  
> -- 
> 2.10.2.dirty