Re: [PATCH] PNPACPI: Enable PNPACPI _PSx Support, v3

[Witold Szczeponik <Witold.Szczeponik@gmx.net>]

yakui_zhao wrote:

>     Very good patch.
>     Do you have the hardware on which the dedicated power source is
> required by the serial port(PnP device) in your hand?
> 

Yes, I have an IBM ThinkPad 600E. I need this patch in order to
be able receive accurate time using a DCF77 receiver attached
to the serial port.

[snip]

>> -	if (ACPI_FAILURE(status))
>> +	if (ACPI_FAILURE(acpi_set_current_resources(handle, &buffer)))
>>   		ret = -EINVAL;
>> +	else if (acpi_bus_power_manageable(handle))
>> +		ret = acpi_bus_set_power(handle, ACPI_STATE_D0);
> How about changing the power state before calling _SRS object?

I recall reading something in the ACPI spec that says that the power
needs to be set after the device was enabled.  But the main driver
for this order (_SRS followed by _PS0) is the symmetry to the required
_PS3 followed by _DIS (according to the spec).

[snip]

--- Witold