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 PNP_DRIVER_RES_DO_NOT_CHANGE bit.
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 drzeus-list@drzeus.cx Tue, 29 Nov 2005 09:09:32 +0100 committer Jaroslav Kysela perex@suse.cz 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 ambx1@neo.rr.com Cc: Jaroslav Kysela perex@suse.cz Cc: Takashi Iwai tiwai@suse.de
Signed-off-by: Pierre Ossman drzeus@drzeus.cx Signed-off-by: Andrew Morton akpm@osdl.org Signed-off-by: Takashi Iwai tiwai@suse.de
Jaroslav
----- Jaroslav Kysela perex@perex.cz Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc.