Re: [PATCH v1 2/2] of: platform: Mark bus devices nodes with FWNODE_FLAG_NEVER_PROBES

Saravana Kannan
2021-09-02T17:21:33Z

On Wed, Sep 1, 2021 at 7:55 PM Saravana Kannan <saravanak@google.com> wrote:
>
> We don't want fw_devlink creating device links for bus devices as
> they'll never probe. So mark those device node with this flag.
>
> Signed-off-by: Saravana Kannan <saravanak@google.com>
> ---
> drivers/of/platform.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index 74afbb7a4f5e..42b3936d204a 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -392,6 +392,22 @@ static int of_platform_bus_create(struct device_node *bus,
> if (!dev || !of_match_node(matches, bus))
> return 0;
>
> + /*
> + * If the bus node has only one compatible string value and it has
> + * matched as a bus node, it's never going to get probed by a device
> + * driver. So flag it as such so that fw_devlink knows not to create
> + * device links with this device.
> + *
> + * This doesn't catch all devices that'll never probe, but this is good
> + * enough for now.
> + *
> + * This doesn't really work for PPC because of how it uses
> + * of_platform_bus_probe() to add normal devices. So ignore PPC cases.
> + */
> + if (!IS_ENABLED(CONFIG_PPC) &&
> + of_property_count_strings(bus, "compatible") == 1)
> + bus->fwnode.flags |= FWNODE_FLAG_NOT_DEVICE;

This patch is wrong. This flag should have been FWNODE_FLAG_NEVER_PROBES.

-Saravana

> +
> for_each_child_of_node(bus, child) {
> pr_debug(" create child: %pOF\n", child);
> rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
> --
> 2.33.0.259.gc128427fd7-goog
>