#!/bin/bash

rmmod nvidia
if lsmod | grep -q nvidia; then
    echo "Error: could not unload nvidia module, leaving card turned on"
    exit 1
fi

modprobe acpi_call
if ! lsmod | grep -q acpi_call; then
    echo "Error: acpi_call module not loaded"
    exit 2
fi

acpi_call () {
    echo "$*" > /proc/acpi/call
    cat /proc/acpi/call
}

PSC=$(acpi_call "\_SB.PCI0.P0P4.GFX0._PSC")
case "$PSC" in
    Error*)
        echo "Error: could not read card state ($PSC)"
        exit 3
        ;;
    0x3)
        echo "Card already disabled"
        ;;

    *)
        DSM=$(acpi_call "\_SB.PCI0.P0P4.GFX0._DSM" \
            "{0xF8,0xD8,0x86,0xA4,0xDA,0x0B,0x1B,0x47," \
            "0xA7,0x2B,0x60,0x42,0xA6,0xB5,0xBE,0xE0}" \
            "0x100 0x1A {0x1,0x0,0x0,0x3}")
        case "$DSM" in
            Error*)
                echo "Error: could not prepare card disabling ($DSM)"
                exit 4
                ;;
        esac

        PS3=$(acpi_call "\_SB.PCI0.P0P4.GFX0._PS3")
        case "$PS3" in
            Error*)
                echo "Error: could not put card to sleep ($PS3)"
                exit 5
                ;;
        esac

        PSC=$(acpi_call "\_SB.PCI0.P0P4.GFX0._PSC")
        case "$PSC" in
            Error*)
                echo "Error: could not read card state ($PSC)"
                exit 6
                ;;
            0x3)
                echo "Disabled nVidia card"
                ;;
            *)
                echo "Disabling nVidia card failed ! _PSC returned $PSC"
                exit 7
                ;;
        esac
        ;;
esac