Re: [PATCH RESEND 2/2] serial: 8250: omap: Move pm_runtime_get_sync

From: Andreas Kemnade
Date: Sat Oct 12 2024 - 08:27:28 EST


Am Fri, 11 Oct 2024 12:33:56 -0500
schrieb Judith Mendez <jm@xxxxxx>:

> Currently in omap_8250_shutdown, the dma->rx_running
> flag is set to zero in omap_8250_rx_dma_flush. Next
> pm_runtime_get_sync is called, which is a runtime
> resume call stack which can re-set the flag. When the
> call omap_8250_shutdown returns, the flag is expected
> to be UN-SET, but this is not the case. This is causing
> issues the next time UART is re-opened and omap_8250_rx_dma
> is called. Fix by moving pm_runtime_get_sync before the
> omap_8250_rx_dma_flush.
>
> Signed-off-by: Bin Liu <b-liu@xxxxxx>
> Signed-off-by: Judith Mendez <jm@xxxxxx>

Is this a theorectical problem or some real practical problem?
So you are running a system with runtime pm enabled on serial
console.
How did you come across this issue?
I could run the serial console/getty with runtime pm autosuspend enabled
without issues all the years.

Regards,
Andreas