New GPIO Interface for User Space
summary
Linux deprecates the GPIO sysfs interface (since v4.8) in favor of a GPIO character device that lets user space open a chip, request up to 64 lines at once, and set/get all values with a single ioctl to avoid many context switches. The new UAPI supports pollable per-line events with timestamps, line names and consumer strings, udev-friendly device files, and a tested userspace toolkit libgpiod (CLI: gpioinfo, gpioset, gpiomon; current stable ~0.3.1, 1.0 in progress). A gpio-mockup kernel module verifies ABI behavior and event delivery.
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chapters (21)
- 0:00Introduction
- 0:57What is a GPIO
- 3:34Provider and Consumer
- 8:02Legacy User Space
- 12:36New User Space Interface
- 18:43Line
- 19:59Direct
- 20:27Flex
- 21:07Request
- 23:01Set
- 23:54Events
- 25:15Pulling Events
- 26:23Project History
- 30:06C API
- 31:31Simple API
- 32:06Lowlevel API
- 33:15GPIO Tools
- 34:15GPIO Find
- 36:53GPIO daemon
- 37:44Where to get
- 38:36Questions
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