Re: [PATCH V3 0/3] PNP: Allow PNP resources to be disabled (interface)

["Rafael J. Wysocki" <rjw@sisk.pl>]

Hi,

On Sunday, July 29, 2012, Witold Szczeponik wrote:
> Hello everybody, 
> 
> this simple patch series continues the work begun in commit 
> 18fd470a48396c8795ba7256c5973e92ffa25cb3 where ACPI PNP resource templates 
> with empty/disabled resources are handled.  
> 
> The aim of this patch series is to allow to set resources as "disabled" using 
> the "/sys/bus/pnp/devices/*/resources" interface.  Such "disabled" resources 
> are needed by some vintage IBM ThinkPads like the 600E where some devices need 
> to have their IRQs disabled in order to support all the devices the 600E has. 
> 
> To better understand the motivation, let's look at an excerpt from the 600E's 
> DSDT:
> 
>     Name (PLPT, ResourceTemplate ()
>     {
>         StartDependentFnNoPri ()
>         {
>             IO (Decode16, 0x03BC, 0x03BC, 0x01, 0x04)
>             IRQNoFlags () {7}
>         }
>         /* Some entries deleted */
>         StartDependentFnNoPri ()
>         {
>             IO (Decode16, 0x03BC, 0x03BC, 0x01, 0x04)
>             IRQNoFlags () {}
>         }
>         EndDependentFn ()
>     })
> 
> As one can see, the IRQ line for the last option is empty/disabled.  Also, both 
> options share the same priority, meaning they are equal alternatives.  In order 
> to be able to use the IRQ 7 for some other device, it is necessary to select 
> the second option, which can be done with the patch series applied.

Do I understand correctly that you want to disable those things through
sysfs?

Rafael