[alsa-devel] [PATCH] ALSA: hda: fix: lock reg_lock before calling snd_hdac_bus_update_rirb

[Takashi Iwai]

On Wed, 29 May 2019 22:59:00 +0200,
Bard liao wrote:
> 
> From: Bard Liao <yung-chuan.liao at linux.intel.com>
> 
> The patch is to fix commit 5e13cf6cd64c
> (ALSA: hda: add polling mode in snd_hdac_bus_get_response)
> spin_lock_irq should be called before snd_hdac_bus_update_rirb.
> 
> Signed-off-by: Bard Liao <yung-chuan.liao at linux.intel.com>
> ---
> Takashi,
> 
> Sorry, I make a mistake on the "ALSA: hda: add polling mode in
> snd_hdac_bus_get_response" patch. This patch is a fix for that.

A good catch, merged now.


thanks,

Takashi

> 
> Thanks,
> Bard
> ---
>  sound/hda/hdac_controller.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/sound/hda/hdac_controller.c b/sound/hda/hdac_controller.c
> index a16ac31bda83..d6a91429c058 100644
> --- a/sound/hda/hdac_controller.c
> +++ b/sound/hda/hdac_controller.c
> @@ -239,9 +239,9 @@ int snd_hdac_bus_get_response(struct hdac_bus *bus, unsigned int addr,
>  	timeout = jiffies + msecs_to_jiffies(1000);
>  
>  	for (loopcounter = 0;; loopcounter++) {
> +		spin_lock_irq(&bus->reg_lock);
>  		if (bus->polling_mode)
>  			snd_hdac_bus_update_rirb(bus);
> -		spin_lock_irq(&bus->reg_lock);
>  		if (!bus->rirb.cmds[addr]) {
>  			if (res)
>  				*res = bus->rirb.res[addr]; /* the last value */
> -- 
> 2.17.1
>