2.6.1-mm4: ALSA es1968 DMA alloc problem

[Johannes Stezenbach <js@convergence.de>]

Hi,

the ALSA driver snd_es1968 for my Terratec DMX (ES1978 Maestro 2E)
fails in 2.6.1-mm4 with the following message:

Jan 16 01:59:15 abc vmunix: PCI: Found IRQ 10 for device 0000:00:0e.0
Jan 16 01:59:15 abc vmunix: es1968: not attempting power management.
Jan 16 01:59:16 abc vmunix: es1968: DMA buffer beyond 256MB.
Jan 16 01:59:16 abc vmunix: ES1968 (ESS Maestro): probe of 0000:00:0e.0 failed with error -12

The seems to be caused by the following change:

--- linux-2.6.1/sound/pci/es1968.c      2003-09-27 18:57:48.000000000 -0700
+++ 25/sound/pci/es1968.c       2004-01-15 22:25:44.000000000 -0800
@@ -2538,7 +2567,7 @@ static int __devinit snd_es1968_create(s
                snd_printk("architecture does not support 28bit PCI busmaster DMA\n");
                return -ENXIO;
        }
-       pci_set_dma_mask(pci, 0x0fffffff);
+       pci_set_consistent_dma_mask(pci, 0x0fffffff);
 
        chip = (es1968_t *) snd_magic_kcalloc(es1968_t, 0, GFP_KERNEL);
        if (! chip)

I don't fully understand Documentation/DMA-mapping.txt, and
Documentation/sound/alsa/DocBook/writing-an-alsa-driver.tmpl
says to use pci_set_consistent_dma_mask(). I decided to call
both pci_set_dma_mask() and pci_set_consistent_dma_mask(), and
then the driver works again.

Regards,
Johannes