of_get_child_by_name() takes a reference we'll need to drop
later so when we substitute in top we need to take a reference
as well as just assigning.
Without this patch we hit the following error:
[ 1.246852] OF: ERROR: Bad of_node_put() on /sound-wm8524
[ 1.262261] Hardware name: NXP i.MX8MQ EVK (DT)
[ 1.266807] Workqueue: events deferred_probe_work_func
[ 1.271950] Call trace:
[ 1.274406] dump_backtrace+0x0/0x158
[ 1.278074] show_stack+0x14/0x20
[ 1.281396] dump_stack+0xa8/0xcc
[ 1.284717] of_node_release+0xb0/0xc8
[ 1.288474] kobject_put+0x74/0xf0
[ 1.291879] of_node_put+0x14/0x28
[ 1.295286] __of_get_next_child+0x44/0x70
[ 1.299387] of_get_next_child+0x3c/0x60
[ 1.303315] simple_for_each_link+0x1dc/0x230
[ 1.307676] simple_probe+0x80/0x540
[ 1.311256] platform_drv_probe+0x50/0xa0
This patch is based on an earlier version posted by Kuninori Morimoto
and commit message includes explanations from Mark Brown.
https://patchwork.kernel.org/patch/10814255/
Reported-by: Vicente Bergas <vicencb@gmail.com>
Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
461d854c0d