ps3steampad

Attempt at getting a Steam Controller to work as a gamepad on the PS3.

The reason this doesn't work out of the box is that the controller by default behaves like a keyboard and mouse ("Lizzard Mode" apparently).

Inspired by ps3xpad and the hid-steam Linux driver.

ps3xpad

Reverse engineering notes

Outline

1. PRX startup
2. Start a PPU thread
3. init_usb
4. while running: wait on mutex for each connected controller, read_input check_pad_status unblock mutex
5. on exit start stop_thread
6. in stop_thread set running=false; join start_thread, stop thread, exit
7. in start_thread detach all controllers, shutdown_usb, stop thread

USB

c_pipe

EP0 control pipe

o_pipe (not required)

output pipe used by write_xpad not present on steam controller (endpoint 0x01 or 0x02)

used by:

• xpad(w)_set_led
• xpad(w)_set_rumble

unit_alloc

called by xpad_attach and get_endpoint_desc (callbacks)

xpad_attach

callback passed to CellUsbdLddOps

get_endpoint_desc (not required)

appears to be for wireless only part of usb descriptor callbacks

init_usb

• init 2 mutexes
• init controller handles to -1
• CellUsbdLddOps xpad_ops set name to controller name (from xpad linux driver) cellUsbdRegisterExtraLdd for each possible controller
• same for wireless controllers

read_input

for each connected controller (pad):
  read_input into xpad_data

read_input is a function pointer which differs for wired/wireless controllers.

xpad_read_input for wired controllers:

block ring buffer mutex

# xpadbuf[0] == count
# xpadbuf[1] == size
memcpy ringbuf[2:] to p (new buffer)

cast p to XBOX360_IN_REPORT (HID report)

xpad_read_report

unblock ring buffer mutex

xpad_read_report: maps xbox360 controller HID report to virtual gamepad

CellPadData data;
# bunch of mapping logic. pretty self-explanatory

// send pad data to virtual pad
cellPadLddDataInsert

check_pad_status

basically checks that PS3 virtual gamepads are alive sets LEDs appropriately

hid_steam