linux-stable/include/linux/i8042.h
Dmitry Torokhov 4097461897 Input: i8042 - break load dependency between atkbd/psmouse and i8042
As explained in 1407814240-4275-1-git-send-email-decui@microsoft.com we
have a hard load dependency between i8042 and atkbd which prevents
keyboard from working on Gen2 Hyper-V VMs.

> hyperv_keyboard invokes serio_interrupt(), which needs a valid serio
> driver like atkbd.c.  atkbd.c depends on libps2.c because it invokes
> ps2_command().  libps2.c depends on i8042.c because it invokes
> i8042_check_port_owner().  As a result, hyperv_keyboard actually
> depends on i8042.c.
>
> For a Generation 2 Hyper-V VM (meaning no i8042 device emulated), if a
> Linux VM (like Arch Linux) happens to configure CONFIG_SERIO_I8042=m
> rather than =y, atkbd.ko can't load because i8042.ko can't load(due to
> no i8042 device emulated) and finally hyperv_keyboard can't work and
> the user can't input: https://bugs.archlinux.org/task/39820
> (Ubuntu/RHEL/SUSE aren't affected since they use CONFIG_SERIO_I8042=y)

To break the dependency we move away from using i8042_check_port_owner()
and instead allow serio port owner specify a mutex that clients should use
to serialize PS/2 command stream.

Reported-by: Mark Laws <mdl@60hz.org>
Tested-by: Mark Laws <mdl@60hz.org>
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2016-07-27 14:20:09 -07:00

99 lines
2.1 KiB
C

#ifndef _LINUX_I8042_H
#define _LINUX_I8042_H
/*
* 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.
*/
#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;
#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(bool (*filter)(unsigned char data, unsigned char str,
struct serio *serio));
int i8042_remove_filter(bool (*filter)(unsigned char data, unsigned char str,
struct serio *serio));
#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(bool (*filter)(unsigned char data, unsigned char str,
struct serio *serio))
{
return -ENODEV;
}
static inline int i8042_remove_filter(bool (*filter)(unsigned char data, unsigned char str,
struct serio *serio))
{
return -ENODEV;
}
#endif
#endif