linux-kernel - PNP_DRIVER_RES_DISABLE breaks swsusp at least with snd

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Message-Id: <200801092343.48726.linux@rainbow-software.org>
Date:	Wed, 9 Jan 2008 23:43:47 +0100
From:	Ondrej Zary <linux@...nbow-software.org>
To:	Linux Kernel <linux-kernel@...r.kernel.org>
Cc:	alsa-devel@...a-project.org
Subject: PNP_DRIVER_RES_DISABLE breaks swsusp at least with snd_cs4236

Hello,
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.

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 
module:
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?

-- 
Ondrej Zary
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