I've been asked several times independently over the course of last months for a way to figure out the PID of the user-space process that's holding a specific GPIO line. This does sound like a valid use-case as the user may create a background process that requests some lines and then want to kill it to release those lines. These patches propose to extend the gpio_v2_line_info struct with the consumer's PID which is set to the process ID for user-space consumers and 0 for kernel-space ones. Bartosz Golaszewski (2): gpiolib: un-inline gpiod_request_user() gpiolib: cdev: export the consumer's PID drivers/gpio/gpiolib-cdev.c | 2 ++ drivers/gpio/gpiolib.c | 33 +++++++++++++++++++++++++++++---- drivers/gpio/gpiolib.h | 14 +++----------- include/uapi/linux/gpio.h | 5 ++++- 4 files changed, 38 insertions(+), 16 deletions(-) -- 2.34.1