diff mbox series

[v8,1/8] of/platform: Allow overlays to create platform devices from the root node

Message ID 20240718210513.3801024-2-sboyd@kernel.org
State Accepted
Commit 814cff595d1ff6079fb4df2fd8ceeb0b6ad2d221
Headers show
Series clk: Add kunit tests for fixed rate and parent data | expand

Commit Message

Stephen Boyd July 18, 2024, 9:05 p.m. UTC 
We'd like to apply overlays to the root node in KUnit so we can test
platform devices created as children of the root node.

On some architectures (powerpc), the root node isn't marked with
OF_POPULATED_BUS. If an overlay tries to modify the root node on these
platforms it will fail, while on other platforms, such as ARM, it will
succeed. This is because the root node is marked with OF_POPULATED_BUS
by of_platform_default_populate_init() calling
of_platform_default_populate() with NULL as the first argument.

Loosen the requirement here so that platform devices can be created for
nodes created as children of the root node via DT overlays even if the
platform bus wasn't populated for the root node.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Cc: Saravana Kannan <saravanak@google.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
[sboyd@kernel.org: Folded in condition fix]
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
---
 drivers/of/platform.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

Comments

Stephen Boyd July 29, 2024, 10:37 p.m. UTC | #1 
Quoting Stephen Boyd (2024-07-18 14:05:00)
> We'd like to apply overlays to the root node in KUnit so we can test
> platform devices created as children of the root node.
> 
> On some architectures (powerpc), the root node isn't marked with
> OF_POPULATED_BUS. If an overlay tries to modify the root node on these
> platforms it will fail, while on other platforms, such as ARM, it will
> succeed. This is because the root node is marked with OF_POPULATED_BUS
> by of_platform_default_populate_init() calling
> of_platform_default_populate() with NULL as the first argument.
> 
> Loosen the requirement here so that platform devices can be created for
> nodes created as children of the root node via DT overlays even if the
> platform bus wasn't populated for the root node.
> 
> Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
> Cc: Saravana Kannan <saravanak@google.com>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> [sboyd@kernel.org: Folded in condition fix]
> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
> ---

Applied to clk-next
diff mbox series

Patch

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 389d4ea6bfc1..86be4dfb9323 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -732,11 +732,14 @@  static int of_platform_notify(struct notifier_block *nb,
 	struct of_reconfig_data *rd = arg;
 	struct platform_device *pdev_parent, *pdev;
 	bool children_left;
+	struct device_node *parent;
 
 	switch (of_reconfig_get_state_change(action, rd)) {
 	case OF_RECONFIG_CHANGE_ADD:
-		/* verify that the parent is a bus */
-		if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
+		parent = rd->dn->parent;
+		/* verify that the parent is a bus (or the root node) */
+		if (!of_node_is_root(parent) &&
+		    !of_node_check_flag(parent, OF_POPULATED_BUS))
 			return NOTIFY_OK;	/* not for us */
 
 		/* already populated? (driver using of_populate manually) */
@@ -749,7 +752,7 @@  static int of_platform_notify(struct notifier_block *nb,
 		 */
 		rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE;
 		/* pdev_parent may be NULL when no bus platform device */
-		pdev_parent = of_find_device_by_node(rd->dn->parent);
+		pdev_parent = of_find_device_by_node(parent);
 		pdev = of_platform_device_create(rd->dn, NULL,
 				pdev_parent ? &pdev_parent->dev : NULL);
 		platform_device_put(pdev_parent);