Re: [PATCH v3 9/9] i2c: tegra: Check DMA completion status in addition to left time

From: Thierry Reding
Date: Tue Jan 07 2020 - 07:39:28 EST

On Mon, 06 Jan 2020 04:04:23 +0300, Dmitry Osipenko wrote:
> It is more robust to check completion status in addition to the left time
> in a case of DMA transfer because transfer's completion happens in two
> phases [one is ISR, other is tasklet] and thus it is possible that DMA is
> completed while I2C completion awaiting times out because of the deferred
> notification done by the DMA driver. The DMA completion status becomes
> 100% actual after DMA synchronization. This fixes spurious DMA timeouts
> when system is under load.
> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
> ---
> drivers/i2c/busses/i2c-tegra.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

Tested-by: Thierry Reding <treding@xxxxxxxxxx>