DMA not working

[Lorenzo Bettini <bettini@dsi.unifi.it>]

Hi,

I'm using kernel 2.6.12.4 (vanilla), recompiled, on a Kubuntu, and when 
I try to enable DMA, I get this error:

sudo hdparm -d1 /dev/hdc

/dev/hdc:
 setting using_dma to 1 (on)
 HDIO_SET_DMA failed: Operation not permitted
 using_dma    =  0 (off)

I know that this typically means that the IDE chipset support is not 
compiled in the kernel, but it is:  I have this IDE

lspci | grep IDE
0000:00:1f.1 IDE interface: Intel Corp. 82801DBM (ICH4) Ultra ATA 
Storage Controller (rev 01)

and so I have th module PIIX but the error still remains...

any clue, please?

thanks in advance
	Lorenzo

--
+-----------------------------------------------------+
|  Lorenzo Bettini          ICQ# lbetto, 16080134     |
|  PhD in Computer Science                            |
|  Dip. Sistemi e Informatica, Univ. di Firenze       |
|  Florence - Italy        (GNU/Linux User # 158233)  |
|  Home Page        : http://www.lorenzobettini.it    |
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