From: Andy Shevchenko <andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
To: Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: [PATCH v1 0/2] spi: dw-mid: fix simplex DMA transfers
Date: Wed, 29 Oct 2014 12:37:56 +0200 [thread overview]
Message-ID: <1414579076.2396.62.camel@linux.intel.com> (raw)
In-Reply-To: <20141028224156.GN18557-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
On Tue, 2014-10-28 at 22:41 +0000, Mark Brown wrote:
> On Tue, Oct 28, 2014 at 06:25:00PM +0200, Andy Shevchenko wrote:
> > In current shape the driver relies on both TX and RX transfers when DMA is
> > enabled. In case of simplex transfer the driver will stuck, since call back
> > function will never achieve the proper condition to finish the transfer.
>
> Applied both, thanks.
Thanks!
> Can you please also send a patch for Linus
> setting SPI_MASTER_MUST_RX and SPI_MASTER_MUST_TX - this is a bug which
> should be fixed in mainline but these seem a bit big for merge right
> now, those flags will cause the core to always ensure that both
> directions have data avoiding the issue?
I'm sorry I didn't quite understand that bug.
When those bits are set the core will always provide valid tx_buf and
rx_buf pointers. How would it help us? Currently driver relies on tx_dma
and rx_dma which are provided by clients if I understood correctly.
--
Andy Shevchenko <andriy.shevchenko-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Intel Finland Oy
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next prev parent reply other threads:[~2014-10-29 10:37 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-28 16:25 [PATCH v1 0/2] spi: dw-mid: fix simplex DMA transfers Andy Shevchenko
[not found] ` <1414513502-595-1-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-10-28 16:25 ` [PATCH v1 1/2] spi: dw-mid: refactor to use helpers Andy Shevchenko
2014-10-28 16:25 ` [PATCH v1 2/2] spi: dw-mid: split rx and tx callbacks when DMA Andy Shevchenko
2014-10-28 22:41 ` [PATCH v1 0/2] spi: dw-mid: fix simplex DMA transfers Mark Brown
[not found] ` <20141028224156.GN18557-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2014-10-29 10:37 ` Andy Shevchenko [this message]
[not found] ` <1414579076.2396.62.camel-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-10-29 11:17 ` Mark Brown
[not found] ` <20141029111712.GE18557-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2014-10-29 13:20 ` Andy Shevchenko
[not found] ` <1414588848.2396.64.camel-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-10-29 22:15 ` Mark Brown
[not found] ` <20141029221530.GQ18557-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2014-10-30 7:10 ` Andy Shevchenko
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