From: Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
To: Andy Shevchenko
<andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
Cc: Vinod Koul <vinod.koul-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>,
dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: [PATCH 02/10] spi: dw-mid: always use duplex transfers when DMA
Date: Wed, 24 Sep 2014 09:44:07 +0100 [thread overview]
Message-ID: <20140924084407.GF4015@sirena.org.uk> (raw)
In-Reply-To: <1411060140-2801-3-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
[-- Attachment #1: Type: text/plain, Size: 511 bytes --]
On Thu, Sep 18, 2014 at 08:08:52PM +0300, Andy Shevchenko wrote:
> In case of DMA we never got things done until we enable both channels. In case
> of receive only or send only mode the user has to provide a dummy buffer.
The driver must never impose such requirements on clients, they
shouldn't need to know about the quirks of the controller. There's
support in the core providing dummy buffers for transmit and receive,
you should use that (possibly extending it so the dummies are only
provided for DMA).
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 473 bytes --]
next prev parent reply other threads:[~2014-09-24 8:44 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-18 17:08 [PATCH 00/10] spi: dw: make DMA working Andy Shevchenko
[not found] ` <1411060140-2801-1-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-09-18 17:08 ` [PATCH 01/10] spi: dw-mid: respect 8 bit mode Andy Shevchenko
[not found] ` <1411060140-2801-2-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-09-24 8:49 ` Mark Brown
2014-09-18 17:08 ` [PATCH 02/10] spi: dw-mid: always use duplex transfers when DMA Andy Shevchenko
[not found] ` <1411060140-2801-3-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-09-24 8:44 ` Mark Brown [this message]
[not found] ` <20140924084407.GF4015-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2014-09-24 10:32 ` Andy Shevchenko
[not found] ` <1411554747.30231.10.camel-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-09-24 11:07 ` Mark Brown
[not found] ` <20140924110747.GG16977-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2014-09-24 12:02 ` Andy Shevchenko
2014-09-18 17:08 ` [PATCH 03/10] spi: dw-mid: terminate ongoing transfers at exit Andy Shevchenko
[not found] ` <1411060140-2801-4-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-09-24 8:49 ` Mark Brown
2014-09-18 17:08 ` [PATCH 04/10] spi: dw-mid: follow new DMAengine workflow Andy Shevchenko
[not found] ` <1411060140-2801-5-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-09-24 8:44 ` Mark Brown
[not found] ` <20140924084453.GG4015-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2014-09-24 10:35 ` Andy Shevchenko
[not found] ` <1411554938.30231.12.camel-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-09-24 11:08 ` Mark Brown
[not found] ` <20140924110849.GH16977-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2014-09-24 11:59 ` Andy Shevchenko
2014-09-18 17:08 ` [PATCH 05/10] spi: dw: disable all interrupts first when pump message Andy Shevchenko
[not found] ` <1411060140-2801-6-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-09-24 8:47 ` Mark Brown
[not found] ` <20140924084724.GH4015-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2014-09-24 10:38 ` Andy Shevchenko
2014-09-18 17:08 ` [PATCH 06/10] spi: dw: introduce support of loopback mode Andy Shevchenko
[not found] ` <1411060140-2801-7-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-09-24 8:49 ` Mark Brown
2014-09-18 17:08 ` [PATCH 07/10] spi: dw: fix style of code in few places Andy Shevchenko
[not found] ` <1411060140-2801-8-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-09-24 8:50 ` Mark Brown
2014-09-18 17:08 ` [PATCH 08/10] spi: dw-mid: move to use core SPI DMA mappings Andy Shevchenko
2014-09-18 17:08 ` [PATCH 09/10] spi: dw-mid: convert to use dw_dmac instead of intel_mid_dma Andy Shevchenko
2014-09-18 17:09 ` [PATCH 10/10] dmaengine: intel-mid-dma: remove the driver Andy Shevchenko
[not found] ` <1411060140-2801-11-git-send-email-andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
2014-10-15 15:07 ` Vinod Koul
[not found] ` <20141015150727.GX1638-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
2014-10-16 8:12 ` Shevchenko, Andriy
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20140924084407.GF4015@sirena.org.uk \
--to=broonie-dgejt+ai2ygdnm+yrofe0a@public.gmane.org \
--cc=andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org \
--cc=dmaengine-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=vinod.koul-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).