Re: [PATCH 5/7] i2c: rcar: : use proper DMAENGINE API for termination

From: Geert Uytterhoeven
Date: Wed Jun 23 2021 - 10:02:39 EST


Hi Wolfram,

On Wed, Jun 23, 2021 at 12:01 PM Wolfram Sang
<wsa+renesas@xxxxxxxxxxxxxxxxxxxx> wrote:
> dmaengine_terminate_all() is deprecated in favor of explicitly saying if
> it should be sync or async. Here, we want dmaengine_terminate_sync()
> because there is no other synchronization code in the driver to handle
> an async case.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>

Thanks for your patch!

Is this safe? The driver is not using a threaded irq, and DMA termination
may be called from the interrupt handler.

Have you tried triggering DMA termination, with lockdep enabled?

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds