android_kernel_samsung_msm8976/include/linux/libps2.h
Dmitry Torokhov 181d683d75 Input: libps2 - additional locking for i8042 ports
The serio ports on i8042 are not completely isolated; while we provide
enough locking to ensure proper serialization when accessing control
and data registers AUX and KBD ports can still have an effect on each
other on PS/2 protocol level. The most prominent effect is that
issuing a command for the device connected to one port may cause
abort of the command currently executing by the device connected to
another port.

Since i8042 nor serio subsystem are not aware of the details of the
PS/2 protocol (length of the commands and their replies and so on) the
locking should be done on libps2 level by adding special handling when
we see that we are dealing with serio port on i8042.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-09-17 23:23:45 -07:00

56 lines
1.8 KiB
C

#ifndef _LIBPS2_H
#define _LIBPS2_H
/*
* Copyright (C) 1999-2002 Vojtech Pavlik
* Copyright (C) 2004 Dmitry Torokhov
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#define PS2_CMD_GETID 0x02f2
#define PS2_CMD_RESET_BAT 0x02ff
#define PS2_RET_BAT 0xaa
#define PS2_RET_ID 0x00
#define PS2_RET_ACK 0xfa
#define PS2_RET_NAK 0xfe
#define PS2_RET_ERR 0xfc
#define PS2_FLAG_ACK 1 /* Waiting for ACK/NAK */
#define PS2_FLAG_CMD 2 /* Waiting for command to finish */
#define PS2_FLAG_CMD1 4 /* Waiting for the first byte of command response */
#define PS2_FLAG_WAITID 8 /* Command execiting is GET ID */
#define PS2_FLAG_NAK 16 /* Last transmission was NAKed */
struct ps2dev {
struct serio *serio;
/* Ensures that only one command is executing at a time */
struct mutex cmd_mutex;
/* Used to signal completion from interrupt handler */
wait_queue_head_t wait;
unsigned long flags;
unsigned char cmdbuf[6];
unsigned char cmdcnt;
unsigned char nak;
};
void ps2_init(struct ps2dev *ps2dev, struct serio *serio);
int ps2_sendbyte(struct ps2dev *ps2dev, unsigned char byte, int timeout);
void ps2_drain(struct ps2dev *ps2dev, int maxbytes, int timeout);
void ps2_begin_command(struct ps2dev *ps2dev);
void ps2_end_command(struct ps2dev *ps2dev);
int __ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command);
int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command);
int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data);
int ps2_handle_response(struct ps2dev *ps2dev, unsigned char data);
void ps2_cmd_aborted(struct ps2dev *ps2dev);
int ps2_is_keyboard_id(char id);
#endif /* _LIBPS2_H */