root/include/linux/i8042.h
/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef _LINUX_I8042_H
#define _LINUX_I8042_H


#include <linux/errno.h>
#include <linux/types.h>

/*
 * Standard commands.
 */

#define I8042_CMD_CTL_RCTR      0x0120
#define I8042_CMD_CTL_WCTR      0x1060
#define I8042_CMD_CTL_TEST      0x01aa

#define I8042_CMD_KBD_DISABLE   0x00ad
#define I8042_CMD_KBD_ENABLE    0x00ae
#define I8042_CMD_KBD_TEST      0x01ab
#define I8042_CMD_KBD_LOOP      0x11d2

#define I8042_CMD_AUX_DISABLE   0x00a7
#define I8042_CMD_AUX_ENABLE    0x00a8
#define I8042_CMD_AUX_TEST      0x01a9
#define I8042_CMD_AUX_SEND      0x10d4
#define I8042_CMD_AUX_LOOP      0x11d3

#define I8042_CMD_MUX_PFX       0x0090
#define I8042_CMD_MUX_SEND      0x1090

/*
 * Status register bits.
 */

#define I8042_STR_PARITY        0x80
#define I8042_STR_TIMEOUT       0x40
#define I8042_STR_AUXDATA       0x20
#define I8042_STR_KEYLOCK       0x10
#define I8042_STR_CMDDAT        0x08
#define I8042_STR_MUXERR        0x04
#define I8042_STR_IBF           0x02
#define I8042_STR_OBF           0x01

/*
 * Control register bits.
 */

#define I8042_CTR_KBDINT        0x01
#define I8042_CTR_AUXINT        0x02
#define I8042_CTR_IGNKEYLOCK    0x08
#define I8042_CTR_KBDDIS        0x10
#define I8042_CTR_AUXDIS        0x20
#define I8042_CTR_XLATE         0x40

struct serio;

/**
 * typedef i8042_filter_t - i8042 filter callback
 * @data: Data received by the i8042 controller
 * @str: Status register of the i8042 controller
 * @serio: Serio of the i8042 controller
 * @context: Context pointer associated with this callback
 *
 * This represents a i8042 filter callback which can be used with i8042_install_filter()
 * and i8042_remove_filter() to filter the i8042 input for platform-specific key codes.
 *
 * Context: Interrupt context.
 * Returns: true if the data should be filtered out, false if otherwise.
 */
typedef bool (*i8042_filter_t)(unsigned char data, unsigned char str, struct serio *serio,
                               void *context);

#if defined(CONFIG_SERIO_I8042) || defined(CONFIG_SERIO_I8042_MODULE)

void i8042_lock_chip(void);
void i8042_unlock_chip(void);
int i8042_command(unsigned char *param, int command);
int i8042_install_filter(i8042_filter_t filter, void *context);
int i8042_remove_filter(i8042_filter_t filter);

#else

static inline void i8042_lock_chip(void)
{
}

static inline void i8042_unlock_chip(void)
{
}

static inline int i8042_command(unsigned char *param, int command)
{
        return -ENODEV;
}

static inline int i8042_install_filter(i8042_filter_t filter, void *context)
{
        return -ENODEV;
}

static inline int i8042_remove_filter(i8042_filter_t filter)
{
        return -ENODEV;
}

#endif

#endif