Re: [PATCH] imx-serial: RX DMA startup latency

[Sascha Hauer]

On Sun, May 14, 2017 at 02:35:15PM +0200, Peter Senna Tschudin wrote:
> 18a4208 introduced a change to reduce the RX DMA latency on the first reception
> when the serial port was opened for reading. However it was claiming a hardirq
> unsafe lock after a hardirq safe lock which is not allowed and causes lockdep
> to complain verbosely.
> 
> This patch changes the code to always start RX DMA earlier, instead of
> relying on the flags used to open the serial port removing the code that
> was looking for the serial file flags.
> 
> CC: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> Signed-off-by: Peter Senna Tschudin <peter.senna@xxxxxxxxxxxxx>
> ---
> Tested on iMX53.

Tested-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>

(on an i.MX6)

Sascha

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