[alsa-devel] Writing an AT91SAM9260-EK Dumb Codec Driver

[Liam Girdwood]

On Mon, 2007-06-18 at 12:07 -0500, Paul Kavan wrote:
> I now have the linux-2.6.22-rc1 kernel booting correctly without the
> aSoC driver activated in .config. However, when I rebuild with the
> aSoC and then boot, I get the following crash:
> 
> .snip.
> Advanced Linux Sound Architecture Driver Version 1.0.14rc4 (Wed May 09
> 09:51:39 2007 UTC).
> ASoC version 0.13.0 
> Unable to handle kernel NULL pointer dereference at virtual address
> 00000001
> pgd = c0004000
> [00000001] *pgd=00000000
> Internal error: Oops: 801 [#1]
> Modules linked in:
> CPU: 0
> PC is at grh_ek_w6811_init+0x4c/0x11c
> LR is at __arm_ioremap_pfn+0x2cc/0x2ec

You have a NULL pointer dereference in grh_ek_w6811_init(), most likely
to be ssc as the dai private data wont be set yet. i.e.

struct at91_ssc_periph *ssc = grh_ek_w6811_dai.cpu_dai->private_data;

Liam