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Groups > linux.kernel > #1210677
| From | Mark Brown <broonie@kernel.org> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH 4/9] spi: sun4i: add DMA support |
| Date | 2015-08-20 21:00 +0200 |
| Message-ID | <pZDe9-50e-7@gated-at.bofh.it> (permalink) |
| References | <pZz0R-7wx-11@gated-at.bofh.it> <pZz0R-7wx-13@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
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On Thu, Aug 20, 2015 at 02:19:46PM -0000, Emilio López wrote:
> - sun4i_spi_drain_fifo(sspi, SUN4I_FIFO_DEPTH);
> + if (sun4i_spi_can_dma(master, spi, tfr) && desc_rx) {
> + /* The receive transfer should be the last one to finish */
> + dma_wait_for_async_tx(desc_rx);
What if it's a transmit only transfer? We'll fall over to this...
> + } else {
> + sun4i_spi_drain_fifo(sspi, SUN4I_FIFO_DEPTH);
> + }
...which manually reads data from the FIFO which doesn't seem like what
we want, won't it conflict with the DMA?
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Re: [PATCH 4/9] spi: sun4i: add DMA support Mark Brown <broonie@kernel.org> - 2015-08-20 21:00 +0200
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