[alsa-devel] PNP_DRIVER_RES_DISABLE breaks swsusp at least with snd_cs4236
rene.herman at keyaccess.nl
Thu Jan 10 02:53:06 CET 2008
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
I'd say that disabling is changing, so isn't this just a braino where
someone meant to write 2 instead of 3?
> The same .flags value is present in many of the ALSA ISA sound drivers.
> Removing that .flags line caused this to appear inlog when loading snd_cs4236
> CS4236+ WSS PnP manual resources are invalid, using auto config
> CS4236+ CTRL PnP manual resources are invalid, using auto config
> CS4236+ MPU401 PnP manual resources are invalid, using auto config
> and the sound now works after resume!
> So the question is: why is this line present?
> Is this a bug? What's the correct fix?
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