From: Bartosz Golaszewski <bgolaszewski@xxxxxxxxxxxx> We're about to merge w V2 user API for GPIO. In user-space we're using the gpio-mockup driver for testing but it's quite cumbersome (needs unloading and reloading to change chip configuration) and not very extensible (config is passed over module params). This series proposes to extend the debugfs interface to support dynamic creation and removal of dummy chips, with extensible options. First 3 patches add some lib functionality we'll use later on. Next 3 contain general gpiolib refactoring and can be picked up independently. Next we refactor gpio-mockup and finally add the delete_device and new_device attributes. Last patch adds documentation for gpio-mockup so I'm not going into detail on how the new interface works - the doc describes it pretty well. Bartosz Golaszewski (23): lib: cmdline: export next_arg() lib: string_helpers: provide kfree_strarray() lib: uaccess: provide getline_from_user() gpiolib: generalize devprop_gpiochip_set_names() for device properties gpiolib: unexport devprop_gpiochip_set_names() gpiolib: switch to simpler IDA interface gpio: mockup: drop unneeded includes gpio: mockup: use pr_fmt() gpio: mockup: use KBUILD_MODNAME gpio: mockup: fix resource leak in error path gpio: mockup: remove the limit on number of dummy chips gpio: mockup: define a constant for chip label size gpio: mockup: pass the chip label as device property gpio: mockup: use the generic 'gpio-line-names' property gpio: mockup: use dynamic device IDs gpio: mockup: refactor the module init function gpio: mockup: rename and move around debugfs callbacks gpio: mockup: require debugfs to build gpio: mockup: add a symlink for the per-chip debugfs directory gpio: mockup: add a lock for dummy device list gpio: mockup: provide a way to delete dummy chips gpio: mockup: provide a way to create new dummy chips Documentation: gpio: add documentation for gpio-mockup .../admin-guide/gpio/gpio-mockup.rst | 87 +++ drivers/gpio/Kconfig | 1 + drivers/gpio/Makefile | 1 - drivers/gpio/gpio-mockup.c | 614 ++++++++++++++---- drivers/gpio/gpiolib-acpi.c | 3 - drivers/gpio/gpiolib-devprop.c | 63 -- drivers/gpio/gpiolib-of.c | 5 - drivers/gpio/gpiolib.c | 62 +- include/linux/gpio/driver.h | 3 - include/linux/string_helpers.h | 2 + include/linux/uaccess.h | 3 + lib/cmdline.c | 1 + lib/string_helpers.c | 22 + lib/usercopy.c | 37 ++ 14 files changed, 705 insertions(+), 199 deletions(-) create mode 100644 Documentation/admin-guide/gpio/gpio-mockup.rst delete mode 100644 drivers/gpio/gpiolib-devprop.c -- 2.26.1