[PATCH] MTD: atmel_nand: Add DMA support to access Nandflash

Hi Ryan,

-----Original Message-----
From: Ryan Mallon [mailto:ryan at bluewatersys.com]
Sent: Tuesday, January 18, 2011 6:42 AM
To: Xu, Hong
Cc: linux-mtd at lists.infradead.org; linux-arm-kernel at lists.infradead.org;
linux-kernel at vger.kernel.org; jamie at jamieiles.com; jacmet at sunsite.dk;
Ferre, Nicolas
Subject: Re: [PATCH] MTD: atmel_nand: Add DMA support to access Nandflash

root at snapper:~$ dmesg | grep -i dma
[    0.850000] atmel_nand atmel_nand: Failed to request DMA channel
[    0.860000] atmel_nand atmel_nand: No DMA support for NAND access.
[    1.530000] at_hdmac at_hdmac: Atmel AHB DMA Controller ( cpy slave ),
8 channels


It looks like the registration for the DMA controller happens after the
NAND driver probe and so the request is failing. I had a quick look, but
I can't see anything that would change this in more recent kernels. Any
ideas?

You got the point. A [Git Pull] has been sent, see
http://article.gmane.org/gmane.linux.kernel/1088240/match=dmaengine+update

In this patch, subsys_initcall will be used so DMA engine will be initialized before NAND driver.
Thanks.

BR,
Hong