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

On Wed, 27 Nov 2024 23:22:31 +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.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap.git for-next

Thanks!

[1/1] regmap: detach regmap from dev on regmap_exit
      commit: 3061e170381af96d1e66799d34264e6414d428a7

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

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

As covered in submitting-patches.rst the inter version changelog should
go after the --- so it is automatically discarded by tooling.

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)
as indicated below:

- You have marked a patch with a "Fixes:" tag for a commit that is in an
  older released kernel, yet you do not have a cc: stable line in the
  signed-off-by area at all, which means that the patch will not be
  applied to any older kernel releases.  To properly fix this, please
  follow the documented rules in the
  Documentation/process/stable-kernel-rules.rst file for how to resolve
  this.

If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
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thanks,

greg k-h's patch email bot