| Date | Fri, 8 May 2020 18:31:34 +0100 | From | Mark Brown <> | Subject | Re: [PATCH 08/17] spi: dw: Clear DMAC register when done or stopped |
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On Fri, May 08, 2020 at 04:29:33PM +0300, Serge Semin wrote: > If DMAC register is left uncleared any further DMAless transfers > may cause the DMAC hardware handshaking interface getting activated. > So the next DMA-based Rx/Tx transaction will be started right > after the dma_async_issue_pending() method is invoked even if no > DMATDLR/DMARDLR conditions are met. This at the same time may cause > the Tx/Rx FIFO buffers underrun/overrun. In order to fix this we > must clear DMAC register after a current DMA-based transaction is > finished.
This also looks like a bugfix so should be pulled forwards to the start of the series if possible. [unhandled content-type:application/pgp-signature] |