The State Transition Manager handles transitioning between power states (idle, on, standby, reset, etc).
Unless otherwise noted, ioctls take in an input buffer of 0x20 bytes and an io buffer of 0x20 bytes, e.g.
static u8 stm_inbuf[0x20] ATTRIBUTE_ALIGN(32); static u8 stm_iobuf[0x20] ATTRIBUTE_ALIGN(32);
retval = IOS_Ioctl(fd, ioctl_no, inbuf, 0x20, outbuf, 0x20);
The contents of the buffers do not matter.
|0x1000||STM_EventHook||This async ioctl will block until the next event happens, at which point the async callback will be called.|
|0x2001||STM_HotReset||This will reset the Wii.|
|0x2003||STM_ShutdownToStandby||This will power the Wii off (red LED).|
|0x2004||STM_ShutdownToIdle||This will power the Wii off (yellow LED), leaving IOS running to service WC24 events. First four bytes of stm_inbuf should be 0xFCA08280 [check]|
|0x2005||STM_Wakeup||This will turn the Wii on (green LED), generally launching the System Menu. This would generally be called by another IOS module that was running while the Wii was in Idle mode.|
|0x3001||STM_GetState||Determines whether or not IOS is currently running in idle mode (yellow light on)|
|0x3002||STM_UnregisterStateEvent||Cancels the EventHook callback set by STM_EventHook|
|0x4001||STM_ReadDDRReg||Reads some DDR registers (in/out 0x20) from D8B4000 + in ???|
|0x4002||STM_ReadDDRReg2||Reads some moar DDR registers (in/out 0x20) from 0xD8B42C4,0xD8B42BE,0xD8B42C8 ???|
|0x5001||STM_SetVIForceDimming||The 32-bit parameter (first 4 bytes of inbuf) changes the brightness of the entire screen. This is used to implement "Screen Saver" functionality (screen dimming).|
|0x6001||STM_FlashLED||This sets the disc drive LED "brightness", input is a 32-bit word from inbuf. This probably can only be used by KD, as using this from Broadway does nothing.(Although STM returned zero.)|
|0x6002||STM_SetIdleLEDMode||Please figure out what I do and update me! 32-bit parameter is passed in as the first word of inbuf. IOS say Forced LED off|
|0x7001||STM_ReadVer||Reads the STM driver version number.|