Re: [PATCH] ALSA: usb-audio: Fix recursive locking on XRUN

[Takashi Sakamoto]

On Sat, Mar 18, 2023 at 09:20:05AM +0900, Takashi Sakamoto wrote:
> 1. Failure at tasklet for URB completion
> 
> It is softIRQ context. The stream lock is not acquired. It doesn't
> matter to call current XRUN API.
> 
> 2. Failure at PCM operation called by ALSA PCM application
> 
> It is process context. The stream lock is acquired before calling driver
> code. When detecting any type of failure, driver code stores the state.
> Then .pointer callback should return SNDRV_PCM_IOCTL_HWSYNC refering to
> the state.

Oops. I did copy-and-paste mistake here... It should be
SNDRV_PCM_POS_XRUN instead of SNDRV_PCM_IOCTL_HWSYNC...


Regards

Takashi Sakamoto