From: linux@arm.linux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 7/9] dmaengine: Move slave caps to dma_device
Date: Sat, 27 Sep 2014 10:28:47 +0100 [thread overview]
Message-ID: <20140927092846.GA5182@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <1411808085-27792-8-git-send-email-maxime.ripard@free-electrons.com>
On Sat, Sep 27, 2014 at 10:54:43AM +0200, Maxime Ripard wrote:
> The previous code was relying on the fact that the slave_caps were to be
> defined on a per channel basis.
>
> However, this proved to be a bit overkill, since every driver filling these so
> far were hardcoding it, disregarding which channel was actually given.
>
> Add these capabilities to the dma_device structure, so that drivers can just
> provide them at probe time, and be done with it.
This is also buggy for the same reason as patch 6.
The only way to do this is to either have a flag day, fixing all drivers
at once (which isn't going to happen) or leave the caps code as-is, and
provide a library function which drivers can hook into the caps callback
which retrieves the information from dma_device.
That way, DMA engine drivers which are using the new method can just
install the new function, and those which haven't been updated with
capabilities can carry on as they are, and are detectable to drivers.
What would be acceptable is to have the DMA engine registration function
spot the lack of DMA caps function and print a warning at boot to
encourage people to add it.
--
FTTC broadband for 0.8mile line: currently at 9.5Mbps down 400kbps up
according to speedtest.net.
next prev parent reply other threads:[~2014-09-27 9:28 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-27 8:54 [PATCH 0/9] dmaengine: Implement generic slave capabilities retrieval Maxime Ripard
2014-09-27 8:54 ` [PATCH 1/9] dmaengine: Make the destination abbreviation coherent Maxime Ripard
2014-09-27 8:54 ` [PATCH 2/9] dmaengine: Make channel allocation callbacks optional Maxime Ripard
2014-09-28 16:07 ` Vinod Koul
2014-10-01 8:39 ` Maxime Ripard
2014-09-27 8:54 ` [PATCH 3/9] dmaengine: Introduce a device_config callback Maxime Ripard
2014-09-28 16:13 ` Vinod Koul
2014-09-28 16:14 ` Vinod Koul
2014-09-27 8:54 ` [PATCH 4/9] dmaengine: split out pause/resume operations from device_control Maxime Ripard
2014-09-27 8:54 ` [PATCH 5/9] dmaengine: Add device_terminate_all callback Maxime Ripard
2014-09-27 8:54 ` [PATCH 6/9] dmaengine: Create a generic dma_slave_caps callback Maxime Ripard
2014-09-27 9:25 ` Russell King - ARM Linux
2014-10-01 8:21 ` Maxime Ripard
2014-09-27 8:54 ` [PATCH 7/9] dmaengine: Move slave caps to dma_device Maxime Ripard
2014-09-27 9:28 ` Russell King - ARM Linux [this message]
2014-10-01 8:27 ` Maxime Ripard
2014-10-01 8:55 ` Russell King - ARM Linux
2014-09-27 8:54 ` [PATCH 8/9] dmaengine: Mark device_control as deprecated Maxime Ripard
2014-09-27 8:54 ` [PATCH 9/9] dmaengine: sun6i: Convert to generic slave_caps Maxime Ripard
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=20140927092846.GA5182@n2100.arm.linux.org.uk \
--to=linux@arm.linux.org.uk \
--cc=linux-arm-kernel@lists.infradead.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).