Message ID | 20240718-mtk-cmdq-fixup-v3-1-e3cbb75bb950@mediatek.com (mailing list archive) |
---|---|
State | New |
Headers | show |
Series | [v3] mailbox: mtk-cmdq: Move devm_mbox_controller_register() after devm_pm_runtime_enable() | expand |
Il 18/07/24 16:17, Jason-JH.Lin via B4 Relay ha scritto: > From: "Jason-JH.Lin" <jason-jh.lin@mediatek.com> > > 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>
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; }