[lkml]   [2008]   [Jan]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [alsa-devel] PNP_DRIVER_RES_DISABLE breaks swsusp at least with snd_cs4236
On Thu, 10 Jan 2008, Rene Herman wrote:

> On 09-01-08 23:43, Ondrej Zary wrote:
> Jaroslav -- in your role as ISA-PnP maintainer and Bjorn, in yours as
> having been foollish enough to touch PnP recently:
> > as hibernation (swsusp) started to work with my CPU, I found that my Turtle
> > Beach Malibu stops working after resume from hibernation. It's caused by fact
> > that the card is not enabled on the pnp layer during resume - and thus card
> > registers are inaccessible (reads return FFs, writes go nowhere).
> >
> > During resume, pnp_bus_resume() in drivers/pnp/driver.c is called for each pnp
> > device. This function calls pnp_start_dev() only when the
> > PNP_DRIVER_RES_DO_NOT_CHANGE bit is NOT seting pnp_drv->flags. But the cs4236
> > driver in sound/isa/cs423x/cs4236.c explicitly sets the .flags to
> > PNP_DRIVER_RES_DISABLE - it's value is 3 and that includes
> Ehm. Isn't that a bit unexpected:
> #define PNP_DRIVER_RES_DO_NOT_CHANGE 0x0001 /* do not change the state
> of the device */
> #define PNP_DRIVER_RES_DISABLE 0x0003 /* ensure the device is
> disabled */
> I'd say that disabling is changing, so isn't this just a braino where
> someone meant to write 2 instead of 3?

It's irrelevant. I think that condition in driver.c in suspend and resume
callbacks is invalid, because PNP_DRIVER_RES_DO_NOT_CHANGE means that
resources should not be changed in the pnp core but only in the driver,
but in suspend/resume process are resources preserved, so the condition
should be removed.

Author of this code is:

author Pierre Ossman <> Tue, 29 Nov 2005 09:09:32 +0100
committer Jaroslav Kysela <> Tue, 03 Jan 2006 12:31:30 +0100

[ALSA] [PATCH] alsa: Improved PnP suspend support

Also use the PnP functions to start/stop the devices during the suspend so
that drivers will not have to duplicate this code.

Cc: Adam Belay <>
Cc: Jaroslav Kysela <>
Cc: Takashi Iwai <>

Signed-off-by: Pierre Ossman <>
Signed-off-by: Andrew Morton <>
Signed-off-by: Takashi Iwai <>


Jaroslav Kysela <>
Linux Kernel Sound Maintainer
ALSA Project, Red Hat, Inc.

 \ /
  Last update: 2008-01-10 09:01    [W:0.096 / U:5.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site