1e2ba5731SMauro Carvalho Chehab.. include:: <isonum.txt> 2e2ba5731SMauro Carvalho Chehab 3e2ba5731SMauro Carvalho Chehab=================== 4e2ba5731SMauro Carvalho ChehabThe userio Protocol 5e2ba5731SMauro Carvalho Chehab=================== 6e2ba5731SMauro Carvalho Chehab 7e2ba5731SMauro Carvalho Chehab 8e2ba5731SMauro Carvalho Chehab:Copyright: |copy| 2015 Stephen Chandler Paul <thatslyude@gmail.com> 9e2ba5731SMauro Carvalho Chehab 10e2ba5731SMauro Carvalho ChehabSponsored by Red Hat 11e2ba5731SMauro Carvalho Chehab 12e2ba5731SMauro Carvalho Chehab 13e2ba5731SMauro Carvalho ChehabIntroduction 14e2ba5731SMauro Carvalho Chehab============= 15e2ba5731SMauro Carvalho Chehab 16e2ba5731SMauro Carvalho ChehabThis module is intended to try to make the lives of input driver developers 17e2ba5731SMauro Carvalho Chehabeasier by allowing them to test various serio devices (mainly the various 18e2ba5731SMauro Carvalho Chehabtouchpads found on laptops) without having to have the physical device in front 19e2ba5731SMauro Carvalho Chehabof them. userio accomplishes this by allowing any privileged userspace program 20e2ba5731SMauro Carvalho Chehabto directly interact with the kernel's serio driver and control a virtual serio 21e2ba5731SMauro Carvalho Chehabport from there. 22e2ba5731SMauro Carvalho Chehab 23e2ba5731SMauro Carvalho ChehabUsage overview 24e2ba5731SMauro Carvalho Chehab============== 25e2ba5731SMauro Carvalho Chehab 26e2ba5731SMauro Carvalho ChehabIn order to interact with the userio kernel module, one simply opens the 27e2ba5731SMauro Carvalho Chehab/dev/userio character device in their applications. Commands are sent to the 28e2ba5731SMauro Carvalho Chehabkernel module by writing to the device, and any data received from the serio 29e2ba5731SMauro Carvalho Chehabdriver is read as-is from the /dev/userio device. All of the structures and 30e2ba5731SMauro Carvalho Chehabmacros you need to interact with the device are defined in <linux/userio.h> and 31e2ba5731SMauro Carvalho Chehab<linux/serio.h>. 32e2ba5731SMauro Carvalho Chehab 33e2ba5731SMauro Carvalho ChehabCommand Structure 34e2ba5731SMauro Carvalho Chehab================= 35e2ba5731SMauro Carvalho Chehab 36e2ba5731SMauro Carvalho ChehabThe struct used for sending commands to /dev/userio is as follows:: 37e2ba5731SMauro Carvalho Chehab 38e2ba5731SMauro Carvalho Chehab struct userio_cmd { 39e2ba5731SMauro Carvalho Chehab __u8 type; 40e2ba5731SMauro Carvalho Chehab __u8 data; 41e2ba5731SMauro Carvalho Chehab }; 42e2ba5731SMauro Carvalho Chehab 43e2ba5731SMauro Carvalho Chehab``type`` describes the type of command that is being sent. This can be any one 44e2ba5731SMauro Carvalho Chehabof the USERIO_CMD macros defined in <linux/userio.h>. ``data`` is the argument 45e2ba5731SMauro Carvalho Chehabthat goes along with the command. In the event that the command doesn't have an 46e2ba5731SMauro Carvalho Chehabargument, this field can be left untouched and will be ignored by the kernel. 47e2ba5731SMauro Carvalho ChehabEach command should be sent by writing the struct directly to the character 48e2ba5731SMauro Carvalho Chehabdevice. In the event that the command you send is invalid, an error will be 49e2ba5731SMauro Carvalho Chehabreturned by the character device and a more descriptive error will be printed 50e2ba5731SMauro Carvalho Chehabto the kernel log. Only one command can be sent at a time, any additional data 51e2ba5731SMauro Carvalho Chehabwritten to the character device after the initial command will be ignored. 52e2ba5731SMauro Carvalho Chehab 53e2ba5731SMauro Carvalho ChehabTo close the virtual serio port, just close /dev/userio. 54e2ba5731SMauro Carvalho Chehab 55e2ba5731SMauro Carvalho ChehabCommands 56e2ba5731SMauro Carvalho Chehab======== 57e2ba5731SMauro Carvalho Chehab 58e2ba5731SMauro Carvalho ChehabUSERIO_CMD_REGISTER 59e2ba5731SMauro Carvalho Chehab~~~~~~~~~~~~~~~~~~~ 60e2ba5731SMauro Carvalho Chehab 61e2ba5731SMauro Carvalho ChehabRegisters the port with the serio driver and begins transmitting data back and 62e2ba5731SMauro Carvalho Chehabforth. Registration can only be performed once a port type is set with 63e2ba5731SMauro Carvalho ChehabUSERIO_CMD_SET_PORT_TYPE. Has no argument. 64e2ba5731SMauro Carvalho Chehab 65e2ba5731SMauro Carvalho ChehabUSERIO_CMD_SET_PORT_TYPE 66e2ba5731SMauro Carvalho Chehab~~~~~~~~~~~~~~~~~~~~~~~~ 67e2ba5731SMauro Carvalho Chehab 68e2ba5731SMauro Carvalho ChehabSets the type of port we're emulating, where ``data`` is the port type being 69e2ba5731SMauro Carvalho Chehabset. Can be any of the macros from <linux/serio.h>. For example: SERIO_8042 70e2ba5731SMauro Carvalho Chehabwould set the port type to be a normal PS/2 port. 71e2ba5731SMauro Carvalho Chehab 72e2ba5731SMauro Carvalho ChehabUSERIO_CMD_SEND_INTERRUPT 73e2ba5731SMauro Carvalho Chehab~~~~~~~~~~~~~~~~~~~~~~~~~ 74e2ba5731SMauro Carvalho Chehab 75e2ba5731SMauro Carvalho ChehabSends an interrupt through the virtual serio port to the serio driver, where 76e2ba5731SMauro Carvalho Chehab``data`` is the interrupt data being sent. 77e2ba5731SMauro Carvalho Chehab 78e2ba5731SMauro Carvalho ChehabUserspace tools 79e2ba5731SMauro Carvalho Chehab=============== 80e2ba5731SMauro Carvalho Chehab 81e2ba5731SMauro Carvalho ChehabThe userio userspace tools are able to record PS/2 devices using some of the 82e2ba5731SMauro Carvalho Chehabdebugging information from i8042, and play back the devices on /dev/userio. The 83e2ba5731SMauro Carvalho Chehablatest version of these tools can be found at: 84e2ba5731SMauro Carvalho Chehab 85e2ba5731SMauro Carvalho Chehab https://github.com/Lyude/ps2emu 86