linux-kernel - Re: [PATCH v2 3/6] dma: Add a jz4740 dmaengine driver

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <51B60D0A.7040307@metafoo.de>
Date:	Mon, 10 Jun 2013 19:29:46 +0200
From:	Lars-Peter Clausen <lars@...afoo.de>
To:	Vinod Koul <vinod.koul@...el.com>
CC:	Ralf Baechle <ralf@...ux-mips.org>,
	Liam Girdwood <lgirdwood@...il.com>,
	Mark Brown <broonie@...nel.org>,
	Maarten ter Huurne <maarten@...ewalker.org>,
	linux-mips@...ux-mips.org, linux-kernel@...r.kernel.org,
	alsa-devel@...a-project.org
Subject: Re: [PATCH v2 3/6] dma: Add a jz4740 dmaengine driver

On 05/30/2013 08:46 PM, Lars-Peter Clausen wrote:
>>> +static int jz4740_dma_alloc_chan_resources(struct dma_chan *c)
>>> +{
>>> +	struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
>>> +
>>> +	chan->jz_chan = jz4740_dma_request(chan, NULL);
>>> +	if (!chan->jz_chan)
>>> +		return -EBUSY;
>>> +
>>> +	jz4740_dma_set_complete_cb(chan->jz_chan, jz4740_dma_complete_cb);
>>> +
>>> +	return 0;
>> Sorry, I didnt reply on this one. The API expects you to allocate a pool of
>> descriptors. These descriptors are to be used in .device_prep_xxx calls later.
> 
> The size of the descriptor is not fixed, so they can not be pre-allocated. And
> this is nothing new either, most of the more recently added dmaengine drivers
> allocate their descriptors on demand.

Vinod, are you ok with this explanation?

- Lars
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/