As described in Documentation/firmware-guide/acpi/gpio-properties.rst a GPIO can be referenced from ACPI ASL _DSD with the "gpios"-property of the form: Package () { "gpios", Package () { ref, index, pin, active_low }} The second patch of this series adds support for specifing a PWM reference in ASL of the form Package () { "pwms", Package () { ref, index, pwm-period [, pwm flags]}} The first patch of this series is necessary to resolve the "ref" in ASL if the table has been loaded by efivar_ssdt_load() or configfs. The third patch of this series makes leds-pwm use the ACPI-enabled PWM framework. v2: - fixes by Pavel Machek and Dan Murphy Nikolaus Voss (3): ACPI: Resolve objects on host-directed table loads PWM framework: add support referencing PWMs from ACPI leds-pwm.c: support ACPI via firmware-node framework drivers/acpi/acpi_configfs.c | 6 +- drivers/acpi/acpica/tbxfload.c | 11 ++++ drivers/leds/leds-pwm.c | 45 +++++++------ drivers/pwm/core.c | 113 +++++++++++++++++++++++++++++++++ include/linux/pwm.h | 9 +++ 5 files changed, 161 insertions(+), 23 deletions(-) -- 2.17.1