Hello, On Fri, Jan 29, 2021 at 02:46:16PM +0100, Bartosz Golaszewski wrote: > From: Bartosz Golaszewski > > This series adds a new GPIO testing module based on configfs committable items > and sysfs. The goal is to provide a testing driver that will be configurable > at runtime (won't need module reload) and easily extensible. The control over > the attributes is also much more fine-grained than in gpio-mockup. > > I am aware that Uwe submitted a virtual driver called gpio-simulator some time > ago and I was against merging it as it wasn't much different from gpio-mockup. > I would ideally want to have a single testing driver to maintain so I am > proposing this module as a replacement for gpio-mockup but since selftests > and libgpiod depend on it and it also has users in the community, we can't > outright remove it until everyone switched to the new interface. As for Uwe's > idea for linking two simulated chips so that one controls the other - while > I prefer to have an independent code path for controlling the lines (hence > the sysfs attributes), I'm open to implementing it in this new driver. It > should be much more feature friendly thanks to configfs than gpio-mockup. Funny you still think about my simulator driver. I recently thought about reanimating it for my private use. The idea was to implement a rotary-encoder driver (that contrast to drivers/input/misc/rotary_encoder.c really implements an encoder and not a decoder). With the two linked chips I can plug drivers/input/misc/rotary_encoder.c on one side and my encoder on the other to test both drivers completely in software. I didn't look into your driver yet, but getting such a driver into mainline would be very welcome! I intend to look into your driver next week, but please don't hold back on merging for my feedback. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ |