[alsa-devel] [PATCH 0/4] ALSA: firewire: block .remove callback of bus

[Takashi Iwai]

On Wed, 10 Oct 2018 08:34:58 +0200,
Takashi Sakamoto wrote:
> 
> Hi,
> 
> In a discussion for devres support[1], I realize difference of unbind
> behaviour of drivers in ALSA firewire stack and in the others. For
> consistency behaviour inner the same subsystem for users, it's better
> to imitate the behaviour.
> 
> Additionally, blocking .remove function simplifies codes to releasing
> device.
> 
> This commit uses 'snd_card_free()' instead of
> 'snd_card_free_when_closed()' in .remove function and performs
> refactoring for release codes.

Would the hot-unplug behavior change with this patch?

For most of other drivers (but for USB), the actual hot-plug/unplug
are unlikely scenario, hence blocking makes sense to assure the safety
unbind.  (Yes, there is also PCI hotplug, but an audio device is
rarely used there.)

But, FireWire is a beast to be plugged / unplugged more often, so the
hot-unplug behavior change is more important to users.


thanks,

Takashi

> 
> [1] http://mailman.alsa-project.org/pipermail/alsa-devel/2018-September/140431.html
> 
> Takashi Sakamoto (4):
>   ALSA: firewire: block .remove callback of bus driver till all of ALSA
>     character devices are released
>   ALSA: firewire: release reference count of firewire unit in .remove
>     callback of bus driver
>   ALSA: bebob/fireworks: simplify handling of local device entry table
>   ALSA: firewire: simplify cleanup process when failing to register
>     sound card
> 
>  sound/firewire/bebob/bebob.c         | 43 ++++++---------------
>  sound/firewire/dice/dice.c           | 35 ++++-------------
>  sound/firewire/digi00x/digi00x.c     | 28 +++++---------
>  sound/firewire/fireface/ff.c         | 28 +++++---------
>  sound/firewire/fireworks/fireworks.c | 56 ++++++++--------------------
>  sound/firewire/isight.c              |  8 ++--
>  sound/firewire/motu/motu.c           | 39 +++++--------------
>  sound/firewire/oxfw/oxfw.c           | 39 +++++--------------
>  sound/firewire/tascam/tascam.c       | 32 +++++-----------
>  9 files changed, 90 insertions(+), 218 deletions(-)
> 
> -- 
> 2.19.0
>