ps2.c File Reference

PS/2 drivers. More...

Macros
#define	__DEBUG_HEADER__   "[PS/2 ]"
	Change header.
#define	__DEBUG_LEVEL__   LOGLEVEL_NOTICE
	Set log level.
#define	PS2_DATA   0x60
	Data signal line.
#define	PS2_STATUS   0x64
	Status and command signal line.
#define	PS2_CTRL_TEST_CONTROLLER   0xAA
	Command to test the PS/2 controller; returns 0x55 for pass, 0xFC for fail.
#define	PS2_CTRL_P1_ENABLE   0xAE
	Command to enable the first PS/2 port; does not return a response.
#define	PS2_CTRL_P1_DISABLE   0xAD
	Command to disable the first PS/2 port; does not return a response.
#define	PS2_CTRL_P1_TEST   0xAB
	Command to test the first PS/2 port; returns status results.
#define	PS2_CTRL_P2_ENABLE   0xA8
	Command to enable the second PS/2 port; does not return a response.
#define	PS2_CTRL_P2_DISABLE   0xA7
	Command to disable the second PS/2 port; does not return a response.
#define	PS2_CTRL_P2_TEST   0xA9
	Command to test the second PS/2 port; applicable only if both ports are supported.
#define	PS2_CTRL_READ_OUTPUT_PORT   0xD0
	Reads the current state of the output port.
#define	PS2_CTRL_WRITE_OUTPUT_PORT   0xD1
	Writes to the output port, controls system reset line and other signals.
#define	PS2_CTRL_READ_RAM_BYTE_0   0x20
	Reads the configuration byte from PS/2 controller RAM.
#define	PS2_CTRL_WRITE_RAM_BYTE_0   0x60
	Writes to the configuration byte in PS/2 controller RAM.
#define	PS2_CTRL_P1_RESET   0xFE
	Resets the first PS/2 port.
#define	PS2_DEV_RESET   0xFF
	Resets the device (keyboard or mouse), triggers self-test.
#define	PS2_DEV_DISABLE_SCAN   0xF5
	Disables scanning, stops the device from sending scancodes.
#define	PS2_DEV_ENABLE_SCAN   0xF4
	Enables scanning, allowing the device to send scancodes.
#define	PS2_DEV_SET_DEFAULTS   0xF6
	Sets the device to its default settings.
#define	PS2_DEV_SET_LED   0xED
	Sets the keyboard LED state (Caps Lock, Num Lock, Scroll Lock).
#define	PS2_DEV_SCAN_CODE_SET   0xF0
	Selects the scancode set (requires additional byte to specify the set).
#define	PS2_DEV_SELF_TEST_PASS   0xAA
	Self-test passed (sent after a reset or power-up).
#define	PS2_DEV_SET_TYPEMATIC_ACK   0xFA
	Acknowledges the Set Typematic Rate/Delay command.
#define	PS2_DEV_OVERRUN   0xFF
	Indicates a buffer overrun during communication.
#define	PS2_ECHO_RES   0xEE
	Response indicating the controller received an "echo" command (0xEE).
#define	PS2_TEST_FAIL1   0xFC
	Response indicating self-test failure (after 0xFF reset command or power-up).
#define	PS2_TEST_FAIL2   0xFD
	Response indicating self-test failure (after 0xFF reset command or power-up).
#define	PS2_RESEND   0xFE
	Response requesting the controller to resend the last command sent.
#define	PS2_STATUS_OUTPUT_FULL   0x01
	Output buffer is full, data is available to be read.
#define	PS2_STATUS_INPUT_FULL   0x02
	Input buffer is full, cannot send another command until it's clear.
#define	PS2_STATUS_SYSTEM   0x04
	"System" flag, distinguishes between system and non-system events.
#define	PS2_STATUS_COMMAND   0x08
	1 if data in input buffer is a command, 0 if it's data.
#define	PS2_STATUS_TIMEOUT   0x40
	Timeout error has occurred.
#define	PS2_STATUS_PARITY_ERROR   0x80
	Parity error occurred during communication.

Functions
void	ps2_write_data (unsigned char data)
	Writes a byte of data to the PS/2 device. More...
void	ps2_write_command (unsigned char command)
	Sends a command to the PS/2 controller. More...
unsigned char	ps2_read_data (void)
	Reads a byte of data from the PS/2 device. More...
static unsigned char	__ps2_get_controller_status (void)
	Reads the PS2 controller status. More...
static void	__ps2_set_controller_status (unsigned char status)
	Sets the PS2 controller status. More...
static int	__ps2_is_dual_channel (void)
	Checks if the PS2 controller is dual channel. More...
static void	__ps2_enable_first_port (void)
	Enables the first PS2 port.
static void	__ps2_enable_second_port (void)
	Enables the second PS2 port.
static void	__ps2_disable_first_port (void)
	Disables the first PS2 port.
static void	__ps2_disable_second_port (void)
	Disables the second PS2 port.
static void	__ps2_write_first_port (unsigned char byte)
	Writes a byte of data to the first PS/2 port (typically for a keyboard). More...
static void	__ps2_write_second_port (unsigned char byte)
	Writes a byte of data to the second PS/2 port (typically for a mouse). More...
static const char *	__ps2_get_response_error_message (unsigned response)
	Returns the string describing the received response. More...
int	ps2_initialize (void)
	Initializes ps2 devices. More...

Detailed Description

PS/2 drivers.

Copyright

(c) 2014-2024 This file is distributed under the MIT License. See LICENSE.md for details.

Function Documentation

__ps2_get_controller_status()

static unsigned char __ps2_get_controller_status ( void  )

inlinestatic

Reads the PS2 controller status.

Returns

the PS2 controller status.

__ps2_get_response_error_message()

static const char* __ps2_get_response_error_message ( unsigned  response )

static

Returns the string describing the received response.

Parameters

response

the response received from the PS2 device.

Returns

the string describing the received response.

__ps2_is_dual_channel()

static int __ps2_is_dual_channel ( void  )

inlinestatic

Checks if the PS2 controller is dual channel.

Returns

1 if dual channel, 0 otherwise.

__ps2_set_controller_status()

static void __ps2_set_controller_status ( unsigned char  status )

inlinestatic

Sets the PS2 controller status.

Parameters

status

the PS2 controller status.

__ps2_write_first_port()

static void __ps2_write_first_port ( unsigned char  byte )

inlinestatic

Writes a byte of data to the first PS/2 port (typically for a keyboard).

Parameters

byte	The value to write to the first PS/2 port.

__ps2_write_second_port()

static void __ps2_write_second_port ( unsigned char  byte )

inlinestatic

Writes a byte of data to the second PS/2 port (typically for a mouse).

Parameters

byte	The value to write to the second PS/2 port.

ps2_initialize()

int ps2_initialize

(

void

)

Initializes ps2 devices.

Returns

0 on success, 1 on failure.

ps2_read_data()

unsigned char ps2_read_data

(

void

)

Reads a byte of data from the PS/2 device.

This function waits until data is available in the output buffer of the PS/2 controller. Once data is available, it reads and returns the byte from the PS/2 data register.

Returns

The byte of data read from the PS/2 device.

ps2_write_command()

void ps2_write_command

(

unsigned char

command

)

Sends a command to the PS/2 controller.

This function waits until the input buffer of the PS/2 controller is empty before writing the specified command to the PS/2 command register.

Parameters

command

The command byte to be sent to the PS/2 controller.

ps2_write_data()

void ps2_write_data

(

unsigned char

data

)

Writes a byte of data to the PS/2 device.

This function waits until the input buffer of the PS/2 controller is empty before sending the specified data byte to the PS/2 data register.

Parameters

data	The byte of data to be sent to the PS/2 device.