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mailbox: mtk-cmdq: Move devm_mbox_controller_register() after devm_pm_runtime_enable()

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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: 623a6143a8 ("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>
This commit is contained in:
Jason-JH.Lin 2024-07-18 22:17:04 +08:00 committed by Jassi Brar
parent 0e3bb6ee88
commit a8bd68e432
1 changed files with 6 additions and 6 deletions
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12
drivers/mailbox/mtk-cmdq-mailbox.c
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@ -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;
}