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 --- sound/soc/generic/simple-card.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/soc/generic/simple-card.c b/sound/soc/generic/simple-card.c index 08df261024cf..dc18c4492955 100644 --- a/sound/soc/generic/simple-card.c +++ b/sound/soc/generic/simple-card.c @@ -445,7 +445,7 @@ static int simple_for_each_link(struct simple_priv *priv, /* Check if it has dai-link */ node = of_get_child_by_name(top, PREFIX "dai-link"); if (!node) { - node = top; + node = of_node_get(top); is_top = 1; }