Re: [PATCH v2] regmap: detach regmap from dev on regmap_exit

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Wed, Nov 27, 2024 at 11:22:31PM +0200, Cosmin Tanislav wrote:
> At the end of __regmap_init(), if dev is not NULL, regmap_attach_dev()
> is called, which adds a devres reference to the regmap, to be able to
> retrieve a dev's regmap by name using dev_get_regmap().
> 
> When calling regmap_exit, the opposite does not happen, and the
> reference is kept until the dev is detached.
> 
> Add a regmap_detach_dev() function, export it and call it in
> regmap_exit(), to make sure that the devres reference is not kept.
> 
> V2:
>  * switch to static function
> 
> Fixes: 72b39f6f2b5a ("regmap: Implement dev_get_regmap()")
> Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com>
> ---
>  drivers/base/regmap/regmap.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
> index 53131a7ede0a6..e3e2afc2c83c6 100644
> --- a/drivers/base/regmap/regmap.c
> +++ b/drivers/base/regmap/regmap.c
> @@ -598,6 +598,17 @@ int regmap_attach_dev(struct device *dev, struct regmap *map,
>  }
>  EXPORT_SYMBOL_GPL(regmap_attach_dev);
>  
> +static int dev_get_regmap_match(struct device *dev, void *res, void *data);
> +
> +static int regmap_detach_dev(struct device *dev, struct regmap *map)
> +{
> +	if (!dev)
> +		return 0;
> +
> +	return devres_release(dev, dev_get_regmap_release,
> +			      dev_get_regmap_match, (void *)map->name);
> +}
> +
>  static enum regmap_endian regmap_get_reg_endian(const struct regmap_bus *bus,
>  					const struct regmap_config *config)
>  {
> @@ -1445,6 +1456,7 @@ void regmap_exit(struct regmap *map)
>  {
>  	struct regmap_async *async;
>  
> +	regmap_detach_dev(map->dev, map);
>  	regcache_exit(map);
>  
>  	regmap_debugfs_exit(map);
> -- 
> 2.47.0
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
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