Re: [RFC PATCH] software node: Skip duplicated software_node sysfs

[Qian Cai <quic_qiancai@quicinc.com>]

On Tue, Nov 16, 2021 at 05:29:56PM +0100, Rafael J. Wysocki wrote:
> > Frist, fixes all dev->fwnode / dev.fwnode to use dev_fwnode(). This
> > could be a standalone tree-wide patchset going out to avoid
> > heavy-lifting later.
> >
> > Then, we can create another patchset on top. I have audited
> > "irq_domain" but not seen any "secondary" leakage. Struct
> > "cht_int33fe_data" does have some need to fix.
> >
> > Rename set_secondary_fwnode() to insert_secondary_fwnode(). Fix things
> > in drivers/base/core.c, swnode.c etc to use the new fwnode_head and
> > anything I can't think of right now.
> >
> > Since we will have multiple "software_node" (secondary fwnode:s) for a
> > single "device". What would be the usual way to deal with a
> > linked-list in the sysfs? I can think of just let "software_node"
> > become a directory to host a list of symlinks named from
> > swnode->id. Thoughts?
> 
> Note that one pointer dereference in ACPI_COMPANION() is enough.

Rafael, we suppose to convert ACPI_COMPANION() to:

to_acpi_device_node(dev_fwnode())

since we will no longer has a dev->fwnode pointer anymore. Do you
suggest to keep that pointer but convert the "secondary" to a linked
list instead?