Re: [PATCH v2 1/6] serial: imx: only set DMA rx-ing when DMA starts
From: Uwe Kleine-König
Date: Thu Jul 06 2017 - 06:02:38 EST
On Thu, Jul 06, 2017 at 10:31:38AM +0200, Romain Perier wrote:
> Hello,
>
>
> Le 05/07/2017 à 15:29, Uwe Kleine-König a écrit :
> > Hello,
> >
> > On Wed, Jul 05, 2017 at 03:07:01PM +0200, Romain Perier wrote:
> >> From: Nandor Han <nandor.han@xxxxxx>
> >>
> >> Avoid the situation when `dma_is_rxing` could incorrectly signal that
> >> DMA RX channel is receiving data in case DMA preparation or sg mapping
> >> fails.
> >>
> >> This commit fixes the issues by moving the assignment of dma_is_rxing
> >> out of imx_disable_rx_int(), then the variable is set to 1 from
> >> start_rx_dma() only when the preparation is correctly done.
> > I'd write:
> >
> > There are a few issues with setting dma_is_rxing to 1 in
> > imx_disable_rx_int:
> >
> > - Currently always after imx_disable_rx_int() the function
> > start_rx_dma() is called. This dependency isn't obvious though.
> > - start_rx_dma() does error checking and might exit without enabling
> > DMA but keeping dma_is_rxing 1.
> >
> > So the more natural place for setting dma_is_rxing to 1 is in
> > start_rx_dma after all errors are checked.
> >
> > If you use this, there is nothing left of Nandor Han's patch and you can
> > drop his authorship.
> >
> > Best regards
> > Uwe
> >
> Ok, will do. No other feedback for the rest of the series ? (just to
> know if I send a v3 or If I wait a bit...)
I didn't come around looking in the patches I didn't comment yet.
Best regards
Uwe
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