Re: [alsa-devel] [PATCH] snd-es1968: remove pm_whitelist

[Takashi Iwai <tiwai@suse.de>]

At Thu, 1 Nov 2012 22:58:30 +0100,
Ondrej Zary wrote:
> 
> On Thursday 01 November 2012 22:29:43 Alan Cox wrote:
> > On Thu, 1 Nov 2012 21:55:54 +0100
> >
> > Ondrej Zary <linux@rainbow-software.org> wrote:
> > > pm_whitelist breaks suspend on all non-whitelisted cards for unknown
> > > purpose. Remove it. This fixes suspend on Terratec DMX and SF64-PCE2
> > > cards.
> >
> > Because lots of them broke laptops.
> >
> > Why not just whitelist the ones you know works, given there are ones we
> > know doesn't so your patch is an instant regression guarantee ?
> >
> > (and yes a blacklist might have been brighter but I don't know the
> > history and it's a bit late to fix)
> 
> I wonder what does the suspend/resume code break? Currently, all 
> non-whitelisted cards are broken (not working after resume).

You can't expect anything logical with the broken ACPI support on such
old hardware :)

> The problem with adding cards to the whitelist is that Terratec DMX has 
> generic subsystem ID:
> ESS Technology ES1978 Maestro 2E [125d:1978] (rev 10)
> Subsystem: ESS Technology ES1978 Maestro 2E [125d:1978]
> 
> Adding this to the whitelist does not look like a good idea...

But better than possibly breaking all units without testing.

The fact that the device contains only the ES1978 SSID implies that
it's a PCI sound card, not an on-board device.  Thus the possibility
to regress for such a case is fairly low.  The concern is basically
only for the onboard sound devices on old laptops.


thanks,

Takashi