Input: add generic support for sparse keymaps

More and more devices choose to reimplement support for sparse keymaps
first introduced by wistron driver. Move it into a library module so it
can be easily used by interested parties.

Reviewed-by: Anisse Astier <anisse@astier.eu>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Dmitry Torokhov 2009-12-04 10:22:23 -08:00
parent 6a47081c37
commit 36203c4f3d
6 changed files with 347 additions and 12 deletions

View file

@ -306,6 +306,10 @@ X!Idrivers/video/console/fonts.c
<sect1><title>Matrix keyboars/keypads</title>
!Iinclude/linux/input/matrix_keypad.h
</sect1>
<sect1><title>Sparse keymap support</title>
!Iinclude/linux/input/sparse-keymap.h
!Edrivers/input/sparse-keymap.c
</sect1>
</chapter>
<chapter id="spi">

View file

@ -8,7 +8,7 @@ menu "Input device support"
config INPUT
tristate "Generic input layer (needed for keyboard, mouse, ...)" if EMBEDDED
default y
---help---
help
Say Y here if you have any input device (mouse, keyboard, tablet,
joystick, steering wheel ...) connected to your system and want
it to be available to applications. This includes standard PS/2
@ -27,8 +27,7 @@ if INPUT
config INPUT_FF_MEMLESS
tristate "Support for memoryless force-feedback devices"
default n
---help---
help
Say Y here if you have memoryless force-feedback input device
such as Logitech WingMan Force 3D, ThrustMaster FireStorm Dual
Power 2, or similar. You will also need to enable hardware-specific
@ -52,12 +51,25 @@ config INPUT_POLLDEV
To compile this driver as a module, choose M here: the
module will be called input-polldev.
config INPUT_SPARSEKMAP
tristate "Sparse keymap support library"
help
Say Y here if you are using a driver for an input
device that uses sparse keymap. This option is only
useful for out-of-tree drivers since in-tree drivers
select it automatically.
If unsure, say N.
To compile this driver as a module, choose M here: the
module will be called sparse-keymap.
comment "Userland interfaces"
config INPUT_MOUSEDEV
tristate "Mouse interface" if EMBEDDED
default y
---help---
help
Say Y here if you want your mouse to be accessible as char devices
13:32+ - /dev/input/mouseX and 13:63 - /dev/input/mice as an
emulated IntelliMouse Explorer PS/2 mouse. That way, all user space
@ -73,7 +85,7 @@ config INPUT_MOUSEDEV_PSAUX
bool "Provide legacy /dev/psaux device"
default y
depends on INPUT_MOUSEDEV
---help---
help
Say Y here if you want your mouse also be accessible as char device
10:1 - /dev/psaux. The data available through /dev/psaux is exactly
the same as the data from /dev/input/mice.
@ -103,7 +115,7 @@ config INPUT_MOUSEDEV_SCREEN_Y
config INPUT_JOYDEV
tristate "Joystick interface"
---help---
help
Say Y here if you want your joystick or gamepad to be
accessible as char device 13:0+ - /dev/input/jsX device.
@ -125,7 +137,7 @@ config INPUT_EVDEV
config INPUT_EVBUG
tristate "Event debugging"
---help---
help
Say Y here if you have a problem with the input subsystem and
want all events (keypresses, mouse movements), to be output to
the system log. While this is useful for debugging, it's also
@ -140,7 +152,7 @@ config INPUT_EVBUG
config INPUT_APMPOWER
tristate "Input Power Event -> APM Bridge" if EMBEDDED
depends on INPUT && APM_EMULATION
---help---
help
Say Y here if you want suspend key events to trigger a user
requested suspend through APM. This is useful on embedded
systems where such behaviour is desired without userspace

View file

@ -9,6 +9,7 @@ input-core-objs := input.o input-compat.o ff-core.o
obj-$(CONFIG_INPUT_FF_MEMLESS) += ff-memless.o
obj-$(CONFIG_INPUT_POLLDEV) += input-polldev.o
obj-$(CONFIG_INPUT_SPARSEKMAP) += sparse-keymap.o
obj-$(CONFIG_INPUT_MOUSEDEV) += mousedev.o
obj-$(CONFIG_INPUT_JOYDEV) += joydev.o

View file

@ -212,7 +212,7 @@ EXPORT_SYMBOL(input_allocate_polled_device);
* @dev: device to free
*
* The function frees memory allocated for polling device and drops
* reference to the associated input device (if present).
* reference to the associated input device.
*/
void input_free_polled_device(struct input_polled_dev *dev)
{
@ -258,6 +258,15 @@ int input_register_polled_device(struct input_polled_dev *dev)
return error;
}
/*
* Take extra reference to the underlying input device so
* that it survives call to input_unregister_polled_device()
* and is deleted only after input_free_polled_device()
* has been invoked. This is needed to ease task of freeing
* sparse keymaps.
*/
input_get_device(input);
return 0;
}
EXPORT_SYMBOL(input_register_polled_device);
@ -269,8 +278,6 @@ EXPORT_SYMBOL(input_register_polled_device);
* The function unregisters previously registered polled input
* device from input layer. Polling is stopped and device is
* ready to be freed with call to input_free_polled_device().
* Callers should not attempt to access dev->input pointer
* after calling this function.
*/
void input_unregister_polled_device(struct input_polled_dev *dev)
{
@ -278,7 +285,6 @@ void input_unregister_polled_device(struct input_polled_dev *dev)
&input_polldev_attribute_group);
input_unregister_device(dev->input);
dev->input = NULL;
}
EXPORT_SYMBOL(input_unregister_polled_device);

View file

@ -0,0 +1,250 @@
/*
* Generic support for sparse keymaps
*
* Copyright (c) 2009 Dmitry Torokhov
*
* Derived from wistron button driver:
* Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz>
* Copyright (C) 2005 Bernhard Rosenkraenzer <bero@arklinux.org>
* Copyright (C) 2005 Dmitry Torokhov <dtor@mail.ru>
*
* 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/input.h>
#include <linux/input/sparse-keymap.h>
MODULE_AUTHOR("Dmitry Torokhov <dtor@mail.ru>");
MODULE_DESCRIPTION("Generic support for sparse keymaps");
MODULE_LICENSE("GPL v2");
MODULE_VERSION("0.1");
/**
* sparse_keymap_entry_from_scancode - perform sparse keymap lookup
* @dev: Input device using sparse keymap
* @code: Scan code
*
* This function is used to perform &struct key_entry lookup in an
* input device using sparse keymap.
*/
struct key_entry *sparse_keymap_entry_from_scancode(struct input_dev *dev,
unsigned int code)
{
struct key_entry *key;
for (key = dev->keycode; key->type != KE_END; key++)
if (code == key->code)
return key;
return NULL;
}
EXPORT_SYMBOL(sparse_keymap_entry_from_scancode);
/**
* sparse_keymap_entry_from_keycode - perform sparse keymap lookup
* @dev: Input device using sparse keymap
* @keycode: Key code
*
* This function is used to perform &struct key_entry lookup in an
* input device using sparse keymap.
*/
struct key_entry *sparse_keymap_entry_from_keycode(struct input_dev *dev,
unsigned int keycode)
{
struct key_entry *key;
for (key = dev->keycode; key->type != KE_END; key++)
if (key->type == KE_KEY && keycode == key->keycode)
return key;
return NULL;
}
EXPORT_SYMBOL(sparse_keymap_entry_from_keycode);
static int sparse_keymap_getkeycode(struct input_dev *dev,
int scancode, int *keycode)
{
const struct key_entry *key =
sparse_keymap_entry_from_scancode(dev, scancode);
if (key && key->type == KE_KEY) {
*keycode = key->keycode;
return 0;
}
return -EINVAL;
}
static int sparse_keymap_setkeycode(struct input_dev *dev,
int scancode, int keycode)
{
struct key_entry *key;
int old_keycode;
if (keycode < 0 || keycode > KEY_MAX)
return -EINVAL;
key = sparse_keymap_entry_from_scancode(dev, scancode);
if (key && key->type == KE_KEY) {
old_keycode = key->keycode;
key->keycode = keycode;
set_bit(keycode, dev->keybit);
if (!sparse_keymap_entry_from_keycode(dev, old_keycode))
clear_bit(old_keycode, dev->keybit);
return 0;
}
return -EINVAL;
}
/**
* sparse_keymap_setup - set up sparse keymap for an input device
* @dev: Input device
* @keymap: Keymap in form of array of &key_entry structures ending
* with %KE_END type entry
* @setup: Function that can be used to adjust keymap entries
* depending on device's deeds, may be %NULL
*
* The function calculates size and allocates copy of the original
* keymap after which sets up input device event bits appropriately.
* Before destroying input device allocated keymap should be freed
* with a call to sparse_keymap_free().
*/
int sparse_keymap_setup(struct input_dev *dev,
const struct key_entry *keymap,
int (*setup)(struct input_dev *, struct key_entry *))
{
size_t map_size = 1; /* to account for the last KE_END entry */
const struct key_entry *e;
struct key_entry *map, *entry;
int i;
int error;
for (e = keymap; e->type != KE_END; e++)
map_size++;
map = kcalloc(map_size, sizeof (struct key_entry), GFP_KERNEL);
if (!map)
return -ENOMEM;
memcpy(map, keymap, map_size * sizeof (struct key_entry));
for (i = 0; i < map_size; i++) {
entry = &map[i];
if (setup) {
error = setup(dev, entry);
if (error)
goto err_out;
}
switch (entry->type) {
case KE_KEY:
__set_bit(EV_KEY, dev->evbit);
__set_bit(entry->keycode, dev->keybit);
break;
case KE_SW:
__set_bit(EV_SW, dev->evbit);
__set_bit(entry->sw.code, dev->swbit);
break;
}
}
dev->keycode = map;
dev->keycodemax = map_size;
dev->getkeycode = sparse_keymap_getkeycode;
dev->setkeycode = sparse_keymap_setkeycode;
return 0;
err_out:
kfree(keymap);
return error;
}
EXPORT_SYMBOL(sparse_keymap_setup);
/**
* sparse_keymap_free - free memory allocated for sparse keymap
* @dev: Input device using sparse keymap
*
* This function is used to free memory allocated by sparse keymap
* in an input device that was set up by sparse_keymap_setup().
*/
void sparse_keymap_free(struct input_dev *dev)
{
kfree(dev->keycode);
dev->keycode = NULL;
dev->keycodemax = 0;
dev->getkeycode = NULL;
dev->setkeycode = NULL;
}
EXPORT_SYMBOL(sparse_keymap_free);
/**
* sparse_keymap_report_entry - report event corresponding to given key entry
* @dev: Input device for which event should be reported
* @ke: key entry describing event
* @value: Value that should be reported (ignored by %KE_SW entries)
* @autorelease: Signals whether release event should be emitted for %KE_KEY
* entries right after reporting press event, ignored by all other
* entries
*
* This function is used to report input event described by given
* &struct key_entry.
*/
void sparse_keymap_report_entry(struct input_dev *dev, const struct key_entry *ke,
unsigned int value, bool autorelease)
{
switch (ke->type) {
case KE_KEY:
input_report_key(dev, ke->keycode, value);
input_sync(dev);
if (value && autorelease) {
input_report_key(dev, ke->keycode, 0);
input_sync(dev);
}
break;
case KE_SW:
value = ke->sw.value;
/* fall through */
case KE_VSW:
input_report_switch(dev, ke->sw.code, value);
break;
}
}
EXPORT_SYMBOL(sparse_keymap_report_entry);
/**
* sparse_keymap_report_event - report event corresponding to given scancode
* @dev: Input device using sparse keymap
* @code: Scan code
* @value: Value that should be reported (ignored by %KE_SW entries)
* @autorelease: Signals whether release event should be emitted for %KE_KEY
* entries right after reporting press event, ignored by all other
* entries
*
* This function is used to perform lookup in an input device using sparse
* keymap and report corresponding event. Returns %true if lookup was
* successful and %false otherwise.
*/
bool sparse_keymap_report_event(struct input_dev *dev, unsigned int code,
unsigned int value, bool autorelease)
{
const struct key_entry *ke =
sparse_keymap_entry_from_scancode(dev, code);
if (ke) {
sparse_keymap_report_entry(dev, ke, value, autorelease);
return true;
}
return false;
}
EXPORT_SYMBOL(sparse_keymap_report_event);

View file

@ -0,0 +1,62 @@
#ifndef _SPARSE_KEYMAP_H
#define _SPARSE_KEYMAP_H
/*
* Copyright (c) 2009 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 KE_END 0 /* Indicates end of keymap */
#define KE_KEY 1 /* Ordinary key/button */
#define KE_SW 2 /* Switch (predetermined value) */
#define KE_VSW 3 /* Switch (value supplied at runtime) */
#define KE_IGNORE 4 /* Known entry that should be ignored */
#define KE_LAST KE_IGNORE
/**
* struct key_entry - keymap entry for use in sparse keymap
* @type: Type of the key entry (KE_KEY, KE_SW, KE_VSW, KE_END);
* drivers are allowed to extend the list with their own
* private definitions.
* @code: Device-specific data identifying the button/switch
* @keycode: KEY_* code assigned to a key/button
* @sw.code: SW_* code assigned to a switch
* @sw.value: Value that should be sent in an input even when KE_SW
* switch is toggled. KE_VSW switches ignore this field and
* expect driver to supply value for the event.
*
* This structure defines an entry in a sparse keymap used by some
* input devices for which traditional table-based approach is not
* suitable.
*/
struct key_entry {
int type; /* See KE_* above */
u32 code;
union {
u16 keycode; /* For KE_KEY */
struct { /* For KE_SW, KE_VSW */
u8 code;
u8 value; /* For KE_SW, ignored by KE_VSW */
} sw;
};
};
struct key_entry *sparse_keymap_entry_from_scancode(struct input_dev *dev,
unsigned int code);
struct key_entry *sparse_keymap_entry_from_keycode(struct input_dev *dev,
unsigned int code);
int sparse_keymap_setup(struct input_dev *dev,
const struct key_entry *keymap,
int (*setup)(struct input_dev *, struct key_entry *));
void sparse_keymap_free(struct input_dev *dev);
void sparse_keymap_report_entry(struct input_dev *dev, const struct key_entry *ke,
unsigned int value, bool autorelease);
bool sparse_keymap_report_event(struct input_dev *dev, unsigned int code,
unsigned int value, bool autorelease);
#endif /* _SPARSE_KEYMAP_H */