mailbox: mtk-cmdq: Move devm_mbox_controller_register() after devm_pm_runtime_enable()
When mtk-cmdq unbinds, a WARN_ON message with condition
pm_runtime_get_sync() < 0 occurs.
According to the call tracei below:
cmdq_mbox_shutdown
mbox_free_channel
mbox_controller_unregister
__devm_mbox_controller_unregister
...
The root cause can be deduced to be calling pm_runtime_get_sync() after
calling pm_runtime_disable() as observed below:
1. CMDQ driver uses devm_mbox_controller_register() in cmdq_probe()
to bind the cmdq device to the mbox_controller, so
devm_mbox_controller_unregister() will automatically unregister
the device bound to the mailbox controller when the device-managed
resource is removed. That means devm_mbox_controller_unregister()
and cmdq_mbox_shoutdown() will be called after cmdq_remove().
2. CMDQ driver also uses devm_pm_runtime_enable() in cmdq_probe() after
devm_mbox_controller_register(), so that devm_pm_runtime_disable()
will be called after cmdq_remove(), but before
devm_mbox_controller_unregister().
To fix this problem, cmdq_probe() needs to move
devm_mbox_controller_register() after devm_pm_runtime_enable() to make
devm_pm_runtime_disable() be called after
devm_mbox_controller_unregister().
Fixes: 623a6143a845 ("mailbox: mediatek: Add Mediatek CMDQ driver")
Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
diff --git a/drivers/mailbox/mtk-cmdq-mailbox.c b/drivers/mailbox/mtk-cmdq-mailbox.c
index f1dfce9..4bff735 100644
--- a/drivers/mailbox/mtk-cmdq-mailbox.c
+++ b/drivers/mailbox/mtk-cmdq-mailbox.c
@@ -689,12 +689,6 @@ static int cmdq_probe(struct platform_device *pdev)
cmdq->mbox.chans[i].con_priv = (void *)&cmdq->thread[i];
}
- err = devm_mbox_controller_register(dev, &cmdq->mbox);
- if (err < 0) {
- dev_err(dev, "failed to register mailbox: %d\n", err);
- return err;
- }
-
platform_set_drvdata(pdev, cmdq);
WARN_ON(clk_bulk_prepare(cmdq->pdata->gce_num, cmdq->clocks));
@@ -722,6 +716,12 @@ static int cmdq_probe(struct platform_device *pdev)
pm_runtime_set_autosuspend_delay(dev, CMDQ_MBOX_AUTOSUSPEND_DELAY_MS);
pm_runtime_use_autosuspend(dev);
+ err = devm_mbox_controller_register(dev, &cmdq->mbox);
+ if (err < 0) {
+ dev_err(dev, "failed to register mailbox: %d\n", err);
+ return err;
+ }
+
return 0;
}
