From a8bd68e4329f9a0ad1b878733e0f80be6a971649 Mon Sep 17 00:00:00 2001 From: "Jason-JH.Lin" Date: Thu, 18 Jul 2024 22:17:04 +0800 Subject: [PATCH] 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 Reviewed-by: AngeloGioacchino Del Regno Signed-off-by: Jassi Brar --- drivers/mailbox/mtk-cmdq-mailbox.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/mailbox/mtk-cmdq-mailbox.c b/drivers/mailbox/mtk-cmdq-mailbox.c index f1dfce9e27f5..4bff73532085 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; }