From: Bryan Wu <cooloney@kernel.org>
To: David Brownell <david-b@pacbell.net>,
Andrew Morton <akpm@linux-foundation.org>
Cc: Mike Frysinger <vapier.adi@gmail.com>,
spi-devel-general@lists.sourceforge.net,
linux-kernel@vger.kernel.org,
Vitja Makarov <vitja.makarov@gmail.com>
Subject: Re: [PATCH 01/16] Blackfin SPI Driver: ensure cache coherency before doing DMA
Date: Thu, 5 Feb 2009 17:30:06 +0800 [thread overview]
Message-ID: <386072610902050130k27c6d7far752ac49183bf36ae@mail.gmail.com> (raw)
In-Reply-To: <200811201405.06811.david-b@pacbell.net>
On Fri, Nov 21, 2008 at 6:05 AM, David Brownell <david-b@pacbell.net> wrote:
> On Thursday 20 November 2008, Mike Frysinger wrote:
>> On Thu, Nov 20, 2008 at 16:47, David Brownell wrote:
>
>> > Basically, dma_map_single(), dma_unmap_single() ... and
>> > remember that the caller may have done the mappings for
>> > you already.
>>
>> these arent required to provide coherent memory right ? if that's the
>> case, i can take a look at getting things updated.
>
> Right. If caller provides dma-coherent memory to you, they
> must also have provided the DMA addresses the controller
> driver should be using ... so you won't need dma mapping
> calls on those paths.
>
>
>> > It'd be nice if one of patches snuck in a comment on that
>> > point: "Full duplex only works for non-DMA transfers."
>> > Same rationale: you may know this hardware inside out,
>> > but the next person won't.
>>
>> well, hopefully if they dont know they wont be touching the driver ;).
>> i'll add a comment in this code chunk. thanks for the feedback.
>
> The way it usually works is someone observes a problem and
> then starts experimenting on relevant code. So they learn
> a bit while debugging ... and code authors/maintainers need
> to keep that learning curve from being too steep. ;)
>
> - Dave
>
>
Hi Dave,
As you acked this patchset, is that possible to merge it?
Or need Andrew to keep them in -mm for a while.
Thanks
-Bryan
next prev parent reply other threads:[~2009-02-05 9:30 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-11-18 7:52 Bryan Wu
2008-11-18 7:52 ` [PATCH 01/16] Blackfin SPI Driver: ensure cache coherency before doing DMA Bryan Wu
2008-11-20 20:24 ` David Brownell
2008-11-20 20:58 ` Mike Frysinger
2008-11-20 21:47 ` David Brownell
2008-11-20 21:57 ` Mike Frysinger
2008-11-20 22:05 ` David Brownell
2009-02-05 9:30 ` Bryan Wu [this message]
2009-02-05 23:51 ` David Brownell
2009-02-06 2:31 ` Bryan Wu
2008-11-18 7:52 ` [PATCH 02/16] Blackfin SPI Driver: Fix erroneous SPI Clock divisor calculation Bryan Wu
2008-11-20 20:25 ` David Brownell
2008-11-18 7:52 ` [PATCH 03/16] Blackfin SPI Driver: move bfin_addr_dcachable() and friends into the cacheflush header where it belongs Bryan Wu
2008-11-20 20:26 ` David Brownell
2008-11-18 7:52 ` [PATCH 04/16] Blackfin SPI Driver: use len_in_bytes when we care about the number of bytes transferred Bryan Wu
2008-11-20 20:25 ` David Brownell
2008-11-18 7:52 ` [PATCH 05/16] Blackfin SPI Driver: pass DMA overflow error to the higher level Bryan Wu
2008-11-20 20:29 ` David Brownell
2008-11-18 7:52 ` [PATCH 06/16] Blackfin SPI Driver: unify duplicated code in dma read/write paths Bryan Wu
2008-11-20 20:32 ` David Brownell
2008-11-18 7:52 ` [PATCH 07/16] Blackfin SPI Driver: drop bogus cast and touchup dma label Bryan Wu
2008-11-20 20:34 ` David Brownell
2008-11-18 7:52 ` [PATCH 08/16] Blackfin SPI Driver: add a few more debug messages in useful places Bryan Wu
2008-11-20 20:35 ` David Brownell
2008-11-18 7:52 ` [PATCH 09/16] Blackfin SPI Driver: do not check for SPI errors if DMA itself did not flag any Bryan Wu
2008-11-18 7:52 ` [PATCH 10/16] Blackfin SPI Driver: use the properl BIT_CTL_xxx defines Bryan Wu
2008-11-20 20:37 ` David Brownell
2008-11-18 7:52 ` [PATCH 11/16] Blackfin SPI Driver: remove duplicated MAX_SPI_SSEL and remove unnecessary array size Bryan Wu
2008-11-18 7:52 ` [PATCH 12/16] Blackfin SPI Driver: get dma working for SPI flashes Bryan Wu
2008-11-20 20:43 ` David Brownell
2008-11-18 7:52 ` [PATCH 13/16] Blackfin SPI Driver: add timeout while waiting for SPIF in dma irq handler Bryan Wu
2008-11-18 7:52 ` [PATCH 14/16] Blackfin SPI Driver: tweak magic spi dma sequence to get it working on BF54x Bryan Wu
2008-11-18 7:52 ` [PATCH 15/16] Blackfin SPI Driver: fix bug - spi controller driver does not assert/deassert CS correctly Bryan Wu
2008-11-20 20:47 ` David Brownell
2008-11-18 7:52 ` [PATCH 16/16] Blackfin SPI Driver: fix bug - correct usage of struct spi_transfer.cs_change Bryan Wu
2008-11-20 20:51 ` David Brownell
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