This is a note to let you know that I've just added the patch titled
of: property: Simplify of_link_to_phandle()
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
of-property-simplify-of_link_to_phandle.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 4a032827daa89350365166b19d14d82fe8219128 Mon Sep 17 00:00:00 2001
From: Saravana Kannan <saravanak@xxxxxxxxxx>
Date: Mon, 6 Feb 2023 17:42:01 -0800
Subject: of: property: Simplify of_link_to_phandle()
From: Saravana Kannan <saravanak@xxxxxxxxxx>
commit 4a032827daa89350365166b19d14d82fe8219128 upstream.
The driver core now:
- Has the parent device of a supplier pick up the consumers if the
supplier never has a device created for it.
- Ignores a supplier if the supplier has no parent device and will never
be probed by a driver
And already prevents creating a device link with the consumer as a
supplier of a parent.
So, we no longer need to find the "compatible" node of the supplier or
do any other checks in of_link_to_phandle(). We simply need to make sure
that the supplier is available in DT.
Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx>
Tested-by: Colin Foster <colin.foster@xxxxxxxxxxxxxxxx>
Tested-by: Sudeep Holla <sudeep.holla@xxxxxxx>
Tested-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Tested-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Tested-by: Luca Weiss <luca.weiss@xxxxxxxxxxxxx> # qcom/sm7225-fairphone-fp4
Link: https://lore.kernel.org/r/20230207014207.1678715-10-saravanak@xxxxxxxxxx
Fixes: eaf9b5612a47 ("driver core: fw_devlink: Don't purge child fwnode's consumer links")
Signed-off-by: Adam Ford <aford173@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/of/property.c | 84 +++++++-------------------------------------------
1 file changed, 13 insertions(+), 71 deletions(-)
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -1062,20 +1062,6 @@ of_fwnode_device_get_match_data(const st
return of_device_get_match_data(dev);
}
-static bool of_is_ancestor_of(struct device_node *test_ancestor,
- struct device_node *child)
-{
- of_node_get(child);
- while (child) {
- if (child == test_ancestor) {
- of_node_put(child);
- return true;
- }
- child = of_get_next_parent(child);
- }
- return false;
-}
-
static struct device_node *of_get_compat_node(struct device_node *np)
{
of_node_get(np);
@@ -1106,71 +1092,27 @@ static struct device_node *of_get_compat
return node;
}
-/**
- * of_link_to_phandle - Add fwnode link to supplier from supplier phandle
- * @con_np: consumer device tree node
- * @sup_np: supplier device tree node
- *
- * Given a phandle to a supplier device tree node (@sup_np), this function
- * finds the device that owns the supplier device tree node and creates a
- * device link from @dev consumer device to the supplier device. This function
- * doesn't create device links for invalid scenarios such as trying to create a
- * link with a parent device as the consumer of its child device. In such
- * cases, it returns an error.
- *
- * Returns:
- * - 0 if fwnode link successfully created to supplier
- * - -EINVAL if the supplier link is invalid and should not be created
- * - -ENODEV if struct device will never be create for supplier
- */
-static int of_link_to_phandle(struct device_node *con_np,
+static void of_link_to_phandle(struct device_node *con_np,
struct device_node *sup_np)
{
- struct device *sup_dev;
- struct device_node *tmp_np = sup_np;
+ struct device_node *tmp_np = of_node_get(sup_np);
- /*
- * Find the device node that contains the supplier phandle. It may be
- * @sup_np or it may be an ancestor of @sup_np.
- */
- sup_np = of_get_compat_node(sup_np);
- if (!sup_np) {
- pr_debug("Not linking %pOFP to %pOFP - No device\n",
- con_np, tmp_np);
- return -ENODEV;
- }
+ /* Check that sup_np and its ancestors are available. */
+ while (tmp_np) {
+ if (of_fwnode_handle(tmp_np)->dev) {
+ of_node_put(tmp_np);
+ break;
+ }
- /*
- * Don't allow linking a device node as a consumer of one of its
- * descendant nodes. By definition, a child node can't be a functional
- * dependency for the parent node.
- */
- if (of_is_ancestor_of(con_np, sup_np)) {
- pr_debug("Not linking %pOFP to %pOFP - is descendant\n",
- con_np, sup_np);
- of_node_put(sup_np);
- return -EINVAL;
- }
+ if (!of_device_is_available(tmp_np)) {
+ of_node_put(tmp_np);
+ return;
+ }
- /*
- * Don't create links to "early devices" that won't have struct devices
- * created for them.
- */
- sup_dev = get_dev_from_fwnode(&sup_np->fwnode);
- if (!sup_dev &&
- (of_node_check_flag(sup_np, OF_POPULATED) ||
- sup_np->fwnode.flags & FWNODE_FLAG_NOT_DEVICE)) {
- pr_debug("Not linking %pOFP to %pOFP - No struct device\n",
- con_np, sup_np);
- of_node_put(sup_np);
- return -ENODEV;
+ tmp_np = of_get_next_parent(tmp_np);
}
- put_device(sup_dev);
fwnode_link_add(of_fwnode_handle(con_np), of_fwnode_handle(sup_np));
- of_node_put(sup_np);
-
- return 0;
}
/**
Patches currently in stable-queue which might be from saravanak@xxxxxxxxxx are
queue-6.1/of-property-simplify-of_link_to_phandle.patch
