[alsa-devel] [PATCH - ice1724 1/1] ALSA: ice1724 - Check for ac97 to avoid kernel oops

[Takashi Iwai]

At Thu,  5 Jan 2012 23:05:18 +0100,
pavel.hofman at ivitera.com wrote:
> 
> From: Pavel Hofman <pavel.hofman at ivitera.com>
> 
> Cards with identical PCI ids but no AC97 config in EEPROM do not have
> the ac97 field initialized. We must check for this case to avoid kernel oops.
> 
> Signed-off-by: Pavel Hofman <pavel.hofman at ivitera.com>

Applied now.  Thanks.


Takashi

> 
> diff --git a/pci/ice1712/amp.c b/pci/ice1712/amp.c
> index e328cfb..e525da2 100644
> --- a/pci/ice1712/amp.c
> +++ b/pci/ice1712/amp.c
> @@ -68,8 +68,11 @@ static int __devinit snd_vt1724_amp_init(struct snd_ice1712 *ice)
>  
>  static int __devinit snd_vt1724_amp_add_controls(struct snd_ice1712 *ice)
>  {
> -	/* we use pins 39 and 41 of the VT1616 for left and right read outputs */
> -	snd_ac97_write_cache(ice->ac97, 0x5a, snd_ac97_read(ice->ac97, 0x5a) & ~0x8000);
> +	if (ice->ac97)
> +		/* we use pins 39 and 41 of the VT1616 for left and right
> +		read outputs */
> +		snd_ac97_write_cache(ice->ac97, 0x5a,
> +			snd_ac97_read(ice->ac97, 0x5a) & ~0x8000);
>  	return 0;
>  }
>  
> -- 
> 1.7.0.4
>