Re: [PATCH v2 22/28] mfd: core: Ensure disabled devices are skiped without aborting

Hi Lee,

On Thu, 27 Jul 2023 10:22:09 +0100 Lee Jones lee@kernel.org wrote:

On Wed, 26 Jul 2023, Herve Codina wrote:

...

The loop searching for a matching device based on its compatible string is aborted when a matching disabled device is found. This abort avoid to add devices as soon as one disabled device is found.

Continue searching for an other device instead of aborting on the first disabled one fixes the issue.

Fixes: 22380b65dc70 ("mfd: mfd-core: Ensure disabled devices are ignored without error") Signed-off-by: Herve Codina herve.codina@bootlin.com

---

drivers/mfd/mfd-core.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c index 0ed7c0d7784e..bcc26e64639a 100644 --- a/drivers/mfd/mfd-core.c +++ b/drivers/mfd/mfd-core.c @@ -146,6 +146,7 @@ static int mfd_add_device(struct device *parent, int id, struct platform_device *pdev; struct device_node *np = NULL; struct mfd_of_node_entry *of_entry, *tmp;

• bool disabled; int ret = -ENOMEM; int platform_id; int r;

@@ -181,13 +182,13 @@ static int mfd_add_device(struct device *parent, int id, goto fail_res;

if (IS_ENABLED(CONFIG_OF) && parent->of_node && cell->of_compatible) {

• disabled = false;  
  

This does not appear to reside in a loop.

Why not set it to false on declaration?

Indeed, I will change in the next iteration and set the value to false at the declaration.

...

for_each_child_of_node(parent->of_node, np) {
	if (of_device_is_compatible(np, cell->of_compatible)) {

• 		/* Ignore 'disabled' devices error free */
  

• 		/* Skip 'disabled' devices */
  	if (!of_device_is_available(np)) {
  

• 			of_node_put(np);  
  

Doesn't this result in a resource leak?

No because we change from 'goto fail_alias' to 'continue' and so we don't exit from the for_each_child_of_node(). The for_each_child_of_node() calls of_get_next_child() and, in turn, calls of_node_put().

Regards, Hervé

...

• 			ret = 0;
  

• 			goto fail_alias;
  

• 			disabled = true;
  

• 			continue;
  	}
  
  	ret = mfd_match_of_node_to_dev(pdev, np, cell);
  

@@ -197,10 +198,17 @@ static int mfd_add_device(struct device *parent, int id, if (ret) goto fail_alias;

• 		break;
  

• 		goto match;
  }
  

  }

• if (disabled) {
  

• 	/* Ignore 'disabled' devices error free */
  

• 	ret = 0;
  

• 	goto fail_alias;
  

• }
  

+match: if (!pdev->dev.of_node) pr_warn("%s: Failed to locate of_node [id: %d]\n", cell->name, platform_id); -- 2.41.0