From: Andy Shevchenko andriy.shevchenko@linux.intel.com
commit d5dcce0c414fcbfe4c2037b66ac69ea5f9b3f75c upstream.
Behind primary and secondary we understand the type of the nodes which might define their ordering. However, if primary node gone, we can't maintain the ordering by definition of the linked list. Thus, by ordering secondary node becomes first in the list. But in this case the meaning of it is still secondary (or auxiliary). The type of the node is maintained by the secondary pointer in it:
secondary pointer Meaning NULL or valid primary node ERR_PTR(-ENODEV) secondary node
So, if by some reason we do the following sequence of calls
set_primary_fwnode(dev, NULL); set_primary_fwnode(dev, primary);
we should preserve secondary node.
This concept is supported by the description of set_primary_fwnode() along with implementation of set_secondary_fwnode(). Hence, fix the commit c15e1bdda436 to follow this as well.
Fixes: c15e1bdda436 ("device property: Fix the secondary firmware node handling in set_primary_fwnode()") Cc: Ferry Toth fntoth@gmail.com Signed-off-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Reviewed-by: Heikki Krogerus heikki.krogerus@linux.intel.com Tested-by: Ferry Toth fntoth@gmail.com Cc: 5.9+ stable@vger.kernel.org # 5.9+ Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/base/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -3414,7 +3414,7 @@ void set_primary_fwnode(struct device *d } else { if (fwnode_is_primary(fn)) { dev->fwnode = fn->secondary; - fn->secondary = NULL; + fn->secondary = ERR_PTR(-ENODEV); } else { dev->fwnode = NULL; }