Messages in this thread | | | Date | Wed, 5 Jul 2017 15:29:10 +0200 | From | Uwe Kleine-König <> | Subject | Re: [PATCH v2 1/6] serial: imx: only set DMA rx-ing when DMA starts |
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Hello,
On Wed, Jul 05, 2017 at 03:07:01PM +0200, Romain Perier wrote: > From: Nandor Han <nandor.han@ge.com> > > 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
-- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ |
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