Add support for HID reports?

[latenitefilms]

Not urgent or important... but just incase you've already solved this elsewhere...

Have you got any extensions/libraries for handling generic HID reports (IOHIDDeviceRegisterInputReportCallback)?

I basically am just looking for something that does what the Stream Deck extension does - but more generic where I can supply a manufacturer key, and just see the raw data for testing purposes. Ideally it would have a callback for device connected, device disconnected, and input report.

Thoughts?

[latenitefilms]

Hope you're well @asmagill ! I was messing around with another piece of hardware today, and it reminded me that it would be so helpful to have some kind of Lua-based iokit extension for getting the raw data off HID devices.

I'm currently just using a butchered version of hs.streamdeck and monitoring the Xcode console.

latenitefilms/hammerspoon@c1d33c7

[asmagill]

I've been playing with my iokit module off and on... The battery module needs to be updated for M1 macs, but I seem to be the only one who has noticed, so it's been easy to put off... the initial work I've done leverages that module, so I suspect I'll be wanting to add it soon. At the moment, it's strictly generic IOKit stuff, nothing that uses the specific sub-branches (IOUSB, IOHID, etc.) but I don't think it would be too hard to add... I'll take a closer look at specifically what the streamdeck module is doing and see what I'd have to add, hopefully later this coming week or weekend.

[latenitefilms]

Legend, thanks mate! No rush or pressure - I just wanted to make a note here for myself, so that I remember what I was doing in the past, when future Chris attempts the same thing again.

[gingerbeardman]

I'm trying to get raw data out of an old input device, a Sony USB Jog Controller (PCVA-JC1).

Using WebHID I can see the data, and it changing in realtime as I press the buttons and move the wheel.

So, is it already possible to read the HID Input Report using hs._asm.iokit?

Thanks!

Example input report (button A just pressed)

00 81 00 00

Device info (from WebHID Explorer)

productName: Sony USB Jog Controller
vendorId:    0x054C (1356)
productId:   0x00C4 (196)
opened:      false
collections[0]
  Usage FF02:0001
  Input reports: 0x00
  Output reports: 0x00
Input report 0x00
  24 values * 1 bits (bits 0 to 23)
    Data,Var,Rel
    Usages: 0007:0001 (Keyboard/Keypad > Keyboard ErrorRollOver) to 0007:0018 (Keyboard/Keypad > Keyboard u and U)
    Logical bounds: 0 to 1
Output report 0x00
  24 values * 1 bits (bits 0 to 23)
    Data,Var,Abs
    Usages: 0008:0001 (LED > Num Lock) to 0008:0018 (LED > Ring)
    Logical bounds: 0 to 1

More info

❯ ./hidapitester --vidpid 054c/00c4 --list-detail
054C/00C4: Sony - Sony USB Jog Controller
  vendorId:      0x054C
  productId:     0x00C4
  usagePage:     0xFF02
  usage:         0x0001
  serial_number:  
  interface:     0 
  path: IOService:/AppleARMPE/arm-io/AppleT600xIO/usb-drd0@2280000/AppleT6000USBXHCI@00000000/usb-drd0-port-hs@00100000/Sony USB Jog Controller@00100000/IOUSBHostInterface@0/AppleUserUSBHostHIDDevice

[latenitefilms]

I don't believe there's any current Lua Extension that allows you to do what you want, but I agree, it would be pretty handy!

I'm currently just making new Objective-C Extensions each time I want to support a new device.

[gingerbeardman]

I'm happy to give that a go, is there a recommended starter template?

[latenitefilms]

I'd probably recommend doing what I started doing above, and just duplicating hs.streamdeck and manipulating as required.

There's some more general information here:

https://github.com/Hammerspoon/hammerspoon/blob/master/CONTRIBUTING.md