Hi Stephen,
On Wed, Jul 10, 2024 at 10:14 PM Stephen Boyd sboyd@kernel.org wrote:
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: Stephen Boyd sboyd@kernel.org
Thanks for your patch, which is now commit 98290f295fbcf18f ("of/platform: Allow overlays to create platform devices from the root node") in clk/clk-next.
This causes i2c-demux-pinctrl to fail on the Koelsch development board:
i2c-demux-pinctrl i2c-mux1: failed to setup demux-adapter 0 (-19) i2c-demux-pinctrl i2c-mux2: failed to setup demux-adapter 0 (-19) i2c-demux-pinctrl i2c-mux3: failed to setup demux-adapter 0 (-19) i2c-demux-pinctrl i2c-mux2: Failed to create device link (0x180) with e6ef0000.video i2c-demux-pinctrl i2c-mux2: Failed to create device link (0x180) with e6ef1000.video i2c-demux-pinctrl i2c-mux2: Failed to create device link (0x180) with hdmi-in i2c-demux-pinctrl i2c-mux2: Failed to create device link (0x180) with hdmi-out
and anything relying on I2C connected to these muxes fails, too.
Also, loading the 25LC040 DT overlay[1] on Ebisu using the out-of-tree of-configfs now fails, too.
--- 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) &&
Parent = /soc, so this returns early. Hence of_changeset_apply() [2] didn't add the I2C mux bus, causing of_get_i2c_adapter_by_node() [3] to fail.
of_node_check_flag(parent, OF_POPULATED_BUS))
Oh, you inverted the check for of_node_check_flag(); was that intentional? Re-adding the "!" fixes all issues for me.
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);
[1] https://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers.git/tr... [2] https://elixir.bootlin.com/linux/latest/source/drivers/i2c/muxes/i2c-demux-p... [3] https://elixir.bootlin.com/linux/latest/source/drivers/i2c/muxes/i2c-demux-p...
Gr{oetje,eeting}s,
Geert