Thanks very much for the very helpful info. I have added the GPE to my DSDT and now I can see the GPE counter in /sys/firmware/acpi/interrupts increasing whenever I send an SCI. Further more, I found the function acpi_install_gpe_handler in the kernel, and used it successfully to install a handler in a temporary driver I created. My custom device is an I2C device that I will read input from , whenever my gpe event occurs. Now my question is : this seems to work without declaring a new device in the DSDT , with an HID - as you mentioned - so can I get away with doing things this way , or would it be bad practice ? Thanks, On Mon, Feb 6, 2012 at 10:57 PM, Matthew Garrett <mjg59@xxxxxxxxxxxxx> wrote: > On Mon, Feb 06, 2012 at 11:25:20AM +0800, Daniel Toussaint wrote: > >> I am working on an Intel (ICH8) based system. A custom device on the system >> emits interrupts to a GPI on the ICH8 chip. Currently, as a test, I have >> from userspace configured the GPI we use to send a SCI. This seems to work, >> because I get a "IRQ9 , nobody cared" message from the kernel. >> My questions now are : >> How do I go about and create an ACPI based driver to catch this event ? Or am >> I searching in the wrong direction. >> If I am right, and the driver has to go through ACPI, are changes to the >> ACPI tables in BIOS required ? > > The ACPI tables should declare the device and its resources, along with > a unique _HID() to allow the driver to bind to it. There should also be > a _Lxx or_Exx (depending on whether it's level or edge triggered) method > for the appropriate GPE (which is the GPIO number + 0x10 on ICH8, I > believe) which sends a Notify to the ACPI device. It's then trivial to > write a small Linux acpi driver which will get the notifications. > > -- > Matthew Garrett | mjg59@xxxxxxxxxxxxx -- Gtalk: daniel.toussaint@xxxxxxxxx Skype: supertoussi Cell: +886-915-680-291 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
