mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Viresh Kumar <viresh.kumar@st.com>
To: Linus Walleij <linus.walleij@linaro.org>
Cc: "vinod.koul@intel.com" <vinod.koul@intel.com>,
	"dan.j.williams@intel.com" <dan.j.williams@intel.com>,
	"linux@arm.linux.org.uk" <linux@arm.linux.org.uk>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	Armando VISCONTI <armando.visconti@st.com>,
	Shiraz HASHIM <shiraz.hashim@st.com>,
	Vipin KUMAR <vipin.kumar@st.com>,
	Rajeev KUMAR <rajeev-dlh.kumar@st.com>,
	Deepak SIKRI <deepak.sikri@st.com>,
	Vipul Kumar SAMAR <vipulkumar.samar@st.com>,
	Amit VIRDI <Amit.VIRDI@st.com>,
	Pratyush ANAND <pratyush.anand@st.com>,
	Bhupesh SHARMA <bhupesh.sharma@st.com>,
	"viresh.linux@gmail.com" <viresh.linux@gmail.com>,
	Bhavna YADAV <bhavna.yadav@st.com>,
	Vincenzo FRASCINO <Vincenzo.FRASCINO@st.com>,
	Mirko GARDI <mirko.gardi@st.com>
Subject: Re: [PATCH 2/8] dmaengine: Add flow controller information to dma_slave_config
Date: Wed, 18 Jan 2012 16:10:51 +0530	[thread overview]
Message-ID: <4F16A1B3.5000409@st.com> (raw)
In-Reply-To: <CACRpkdbwZ5h15b0gBJP6xdk5TJt+CSeNRbEB8o2vzp9FbyD9AA@mail.gmail.com>

On 1/18/2012 4:06 PM, Linus Walleij wrote:
> On Tue, Jan 17, 2012 at 10:07 AM, Viresh Kumar <viresh.kumar@st.com> wrote:
>> On 1/17/2012 2:07 PM, Linus Walleij wrote:

> Maybe I should say that it's supposed to transfer information from
> the driver to the DMA engine that:
> 
> 1) The driver naturally "knows", like which physical register address
>   the FIFO is in or burst width etc and the DMA engine has no
>   business knowing.
> 
> 2) That needs to change at runtime, like for example how the PL022
>  driver request 32, 16 or 8 bit wide transfers depending on bus
>  width.
> 
> I think master mode could very well be under (1). So the driver knows
> if this hardware expects the DMA engine to drive the transaction or
> if it's the device itself that should drive it.
> 
> So I'm starting to think like you :-)

:)

>> One more thing. I missed few things in this patch:
>> - Need to update all instances of struct dma_slave_config with
>>        .device_fc = false
> 
> All statically defined structs contain zero == false by default
> so it's not needed.
> 
> Make sure any dynamic allocations (I don't know of any!)
> are kzalloc() though.
> 

I already fixed these in V2.
Most of the drivers created inside routines. They are not getting
initialized to _zero_ , so i had to fix it.

There are few though, who used kzalloc. I didn't touch them.

-- 
viresh

  reply	other threads:[~2012-01-18 10:41 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-16  9:50 [PATCH 0/9] dmaengine: Pl08x and dw_dmac updates Viresh Kumar
2012-01-16  9:50 ` [PATCH 1/8] dmaengine/dw_dmac: Hibernation support in dw_dmac Viresh Kumar
2012-01-16  9:50 ` [PATCH 2/8] dmaengine: Add flow controller information to dma_slave_config Viresh Kumar
2012-01-17  8:37   ` Linus Walleij
2012-01-17  9:07     ` Viresh Kumar
2012-01-18 10:36       ` Linus Walleij
2012-01-18 10:40         ` Viresh Kumar [this message]
2012-01-16  9:50 ` [PATCH 3/8] dmaengine/amba-pl08x: Take flow controller info from DMA_SLAVE_CONFIG Viresh Kumar
2012-01-16  9:50 ` [PATCH 4/8] dmaengine/dw_dmac: Don't use magic number for total number of channels Viresh Kumar
2012-01-16  9:50 ` [PATCH 5/8] dmaengine/dw_dmac: Use platform_get_drvdata instead of accessing dev directly Viresh Kumar
2012-01-16 10:47   ` Sergei Shtylyov
2012-01-16 10:52     ` Viresh Kumar
2012-01-16  9:50 ` [PATCH 6/8] dmaengine/dw_dmac: Don't handle block interrupts Viresh Kumar
2012-01-16  9:50 ` [PATCH 7/8] dmaengine/dw_dmac: Unmap all memory buffers after completion of slave transfers Viresh Kumar
2012-01-16 10:54   ` Russell King - ARM Linux
2012-01-16 11:44     ` Viresh Kumar
2012-01-17  8:52       ` Linus Walleij
2012-01-17  9:07         ` Viresh Kumar
2012-01-18  9:35           ` Russell King - ARM Linux
2012-01-19 17:34           ` Linus Walleij
2012-01-16  9:50 ` [PATCH 8/8] dmaengine/dw_dmac: Add support for DMA_SLAVE_CONFIG Viresh Kumar
2012-01-16 11:42   ` Viresh Kumar
2012-01-17  8:49     ` Linus Walleij
2012-01-17  9:15       ` Viresh Kumar
2012-01-17  9:19         ` Viresh Kumar
2012-01-17 10:19         ` Viresh Kumar
2012-01-17 10:10     ` Jassi Brar
2012-01-17 10:19       ` Viresh Kumar

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=4F16A1B3.5000409@st.com \
    --to=viresh.kumar@st.com \
    --cc=Amit.VIRDI@st.com \
    --cc=Vincenzo.FRASCINO@st.com \
    --cc=armando.visconti@st.com \
    --cc=bhavna.yadav@st.com \
    --cc=bhupesh.sharma@st.com \
    --cc=dan.j.williams@intel.com \
    --cc=deepak.sikri@st.com \
    --cc=linus.walleij@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@arm.linux.org.uk \
    --cc=mirko.gardi@st.com \
    --cc=pratyush.anand@st.com \
    --cc=rajeev-dlh.kumar@st.com \
    --cc=shiraz.hashim@st.com \
    --cc=vinod.koul@intel.com \
    --cc=vipin.kumar@st.com \
    --cc=vipulkumar.samar@st.com \
    --cc=viresh.linux@gmail.com \
    /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

Powered by JetHome