/* ir-register.c - handle IR scancode->keycode tables
*
* Copyright (C) 2009 by Mauro Carvalho Chehab <mchehab@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/input.h>
#include <linux/slab.h>
#include <media/ir-common.h>
/* Sizes are in bytes, 256 bytes allows for 32 entries on x64 */
#define IR_TAB_MIN_SIZE 256
#define IR_TAB_MAX_SIZE 8192
/**
* ir_resize_table() - resizes a scancode table if necessary
* @rc_tab: the ir_scancode_table to resize
* @return: zero on success or a negative error code
*
* This routine will shrink the ir_scancode_table if it has lots of
* unused entries and grow it if it is full.
*/
static int ir_resize_table(struct ir_scancode_table *rc_tab)
{
unsigned int oldalloc = rc_tab->alloc;
unsigned int newalloc = oldalloc;
struct ir_scancode *oldscan = rc_tab->scan;
struct ir_scancode *newscan;
if (rc_tab->size == rc_tab->len) {
/* All entries in use -> grow keytable */
if (rc_tab->alloc >= IR_TAB_MAX_SIZE)
return -ENOMEM;
newalloc *= 2;
IR_dprintk(1, "Growing table to %u bytes\n", newalloc);
}
if ((rc_tab->len * 3 < rc_tab->size) && (oldalloc > IR_TAB_MIN_SIZE)) {
/* Less than 1/3 of entries in use -> shrink keytable */
newalloc /= 2;
IR_dprintk(1, "Shrinking table to %u bytes\n", newalloc);
}
if (newalloc == oldalloc)
return 0;
newscan = kmalloc(newalloc, GFP_ATOMIC);
if (!newscan) {
IR_dprintk(1, "Failed to kmalloc %u bytes\n", newalloc);
return -ENOMEM;
}
memcpy(newscan, rc_tab->scan, rc_tab->len * sizeof(struct ir_scancode));
rc_tab->scan = newscan;
rc_tab->alloc = newalloc;
rc_tab->size = rc_tab->alloc / sizeof(struct ir_scancode);
kfree(oldscan);
return 0;
}
/**
* ir_do_setkeycode() - internal function to set a keycode in the
* scancode->keycode table
* @dev: the struct input_dev device descriptor
* @rc_tab: the struct ir_scancode_table to set the keycode in
* @scancode: the scancode for the ir command
* @keycode: the keycode for the ir command
* @return: -EINVAL if the keycode could not be inserted, otherwise zero.
*
* This routine is used internally to manipulate the scancode->keycode table.
* The caller has to hold @rc_tab->lock.
*/
static int ir_do_setkeycode(struct input_dev *dev,
struct ir_scancode_table *rc_tab,
unsigned scancode, unsigned keycode)
{
unsigned int i;
int old_keycode = KEY_RESERVED;
/* First check if we already have a mapping for this ir command */
for (i = 0; i < rc_tab->len; i++) {
/* Keytable is sorted from lowest to highest scancode */
if (rc_tab->scan[i].scancode > scancode)
break;
else if (rc_tab->scan[i].scancode < scancode)
continue;
old_keycode = rc_tab->scan[i].keycode;
rc_tab->scan[i].keycode = keycode;
/* Did the user wish to remove the mapping? */
if (keycode == KEY_RESERVED || keycode == KEY_UNKNOWN) {
IR_dprintk(1, "#%d: Deleting scan 0x%04x\n",
i, scancode);
rc_tab->len--;
memmove(&rc_tab->scan[i], &rc_tab->scan[i + 1],
(rc_tab->len - i) * sizeof(struct ir_scancode));
}
/* Possibly shrink the keytable, failure is not a problem */
ir_resize_table(rc_tab);
break;
}
if (old_keycode == KEY_RESERVED) {
/* No previous mapping found, we might need to grow the table */
if (ir_resize_table(rc_tab))
return -ENOMEM;
IR_dprintk(1, "#%d: New scan 0x%04x with key 0x%04x\n",
i, scancode, keycode);
/* i is the proper index to insert our new keycode */
memmove(&rc_tab->scan[i + 1], &rc_tab->scan[i],
(rc_tab->len - i) * sizeof(struct ir_scancode));
rc_tab->scan[i].scancode = scancode;
rc_tab->scan[i].keycode = keycode;
rc_tab->len++;
set_bit(keycode, dev->keybit);
} else {
IR_dprintk(1, "#%d: Replacing scan 0x%04x with key 0x%04x\n",
i, scancode, keycode);
/* A previous mapping was updated... */
clear_bit(old_keycode, dev->keybit);
/* ...but another scancode might use the same keycode */
for (i = 0; i < rc_tab->len; i++) {
if (rc_tab->scan[i].keycode == old_keycode) {
set_bit(old_keycode, dev->keybit);
break;
}
}
}
return 0;
}
/**
* ir_setkeycode() - set a keycode in the scancode->keycode table
* @dev: the struct input_dev device descriptor
* @scancode: the desired scancode
* @keycode: result
* @return: -EINVAL if the keycode could not be inserted, otherwise zero.
*
* This routine is used to handle evdev EVIOCSKEY ioctl.
*/
static int ir_setkeycode(struct input_dev *dev,
unsigned int scancode, unsigned int keycode)
{
int rc;
unsigned long flags;
struct ir_input_dev *ir_dev = input_get_drvdata(dev);
struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
spin_lock_irqsave(&rc_tab->lock, flags);
rc = ir_do_setkeycode(dev, rc_tab, scancode, keycode);
spin_unlock_irqrestore(&rc_tab->lock, flags);
return rc;
}
/**
* ir_setkeytable() - sets several entries in the scancode->keycode table
* @dev: the struct input_dev device descriptor
* @to: the struct ir_scancode_table to copy entries to
* @from: the struct ir_scancode_table to copy entries from
* @return: -EINVAL if all keycodes could not be inserted, otherwise zero.
*
* This routine is used to handle table initialization.
*/
static int ir_setkeytable(struct input_dev *dev,
struct ir_scancode_table *to,
const struct ir_scancode_table *from)
{
struct ir_input_dev *ir_dev = input_get_drvdata(dev);
struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
unsigned long flags;
unsigned int i;
int rc = 0;
spin_lock_irqsave(&rc_tab->lock, flags);
for (i = 0; i < from->size; i++) {
rc = ir_do_setkeycode(dev, to, from->scan[i].scancode,
from->scan[i].keycode);
if (rc)
break;
}
spin_unlock_irqrestore(&rc_tab->lock, flags);
return rc;
}
/**
* ir_getkeycode() - get a keycode from the scancode->keycode table
* @dev: the struct input_dev device descriptor
* @scancode: the desired scancode
* @keycode: used to return the keycode, if found, or KEY_RESERVED
* @return: always returns zero.
*
* This routine is used to handle evdev EVIOCGKEY ioctl.
*/
static int ir_getkeycode(struct input_dev *dev,
unsigned int scancode, unsigned int *keycode)
{
int start, end, mid;
unsigned long flags;
int key = KEY_RESERVED;
struct ir_input_dev *ir_dev = input_get_drvdata(dev);
struct ir_scancode_table *rc_tab = &ir_dev->rc_tab;
spin_lock_irqsave(&rc_tab->lock, flags);
start = 0;
end = rc_tab->len - 1;
while (start <= end) {
mid = (start + end) / 2;
if (rc_tab->scan[mid].scancode < scancode)
start = mid + 1;
else if (rc_tab->scan[mid].scancode > scancode)
end = mid - 1;
else {
key = rc_tab->scan[mid].keycode;
break;
}
}
spin_unlock_irqrestore(&rc_tab->lock, flags);
if (key == KEY_RESERVED)
IR_dprintk(1, "unknown key for scancode 0x%04x\n",
scancode);
*keycode = key;
return 0;
}
/**
* ir_g_keycode_from_table() - gets the keycode that corresponds to a scancode
* @input_dev: the struct input_dev descriptor of the device
* @scancode: the scancode that we're seeking
*
* This routine is used by the input routines when a key is pressed at the
* IR. The scancode is received and needs to be converted into a keycode.
* If the key is not found, it returns KEY_RESERVED. Otherwise, returns the
* corresponding keycode from the table.
*/
u32 ir_g_keycode_from_table(struct input_dev *dev, u32 scancode)
{
int keycode;
ir_getkeycode(dev, scancode, &keycode);
if (keycode != KEY_RESERVED)
IR_dprintk(1, "%s: scancode 0x%04x keycode 0x%02x\n",
dev->name, scancode, keycode);
return keycode;
}
EXPORT_SYMBOL_GPL(ir_g_keycode_from_table);
/**
* ir_keyup() - generates input event to cleanup a key press
* @input_dev: the struct input_dev descriptor of the device
*
* This routine is used by the input routines when a key is pressed at the
* IR. It reports a keyup input event via input_report_key().
*/
void ir_keyup(struct input_dev *dev)
{
struct ir_input_dev *ir = input_get_drvdata(dev);
if (!ir->keypressed)
return;
IR_dprintk(1, "keyup key 0x%04x\n", ir->keycode);
input_report_key(dev, ir->keycode, 0);
input_sync(dev);
ir->keypressed = 0;
}
EXPORT_SYMBOL_GPL(ir_keyup);
/**
* ir_keydown() - generates input event for a key press
* @input_dev: the struct input_dev descriptor of the device
* @scancode: the scancode that we're seeking
*
* This routine is used by the input routines when a key is pressed at the
* IR. It gets the keycode for a scancode and reports an input event via
* input_report_key().
*/
void ir_keydown(struct input_dev *dev, int scancode)
{
struct ir_input_dev *ir = input_get_drvdata(dev);
u32 keycode = ir_g_keycode_from_table(dev, scancode);
/* If already sent a keydown, do a keyup */
if (ir->keypressed)
ir_keyup(dev);
if (KEY_RESERVED == keycode)
return;
ir->keycode = keycode;
ir->keypressed = 1;
IR_dprintk(1, "%s: key down event, key 0x%04x, scancode 0x%04x\n",
dev->name, keycode, scancode);
input_report_key(dev, ir->keycode, 1);
input_sync(dev);
}
EXPORT_SYMBOL_GPL(ir_keydown);
static int ir_open(struct input_dev *input_dev)
{
struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
return ir_dev->props->open(ir_dev->props->priv);
}
static void ir_close(struct input_dev *input_dev)
{
struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
ir_dev->props->close(ir_dev->props->priv);
}
/**
* __ir_input_register() - sets the IR keycode table and add the handlers
* for keymap table get/set
* @input_dev: the struct input_dev descriptor of the device
* @rc_tab: the struct ir_scancode_table table of scancode/keymap
*
* This routine is used to initialize the input infrastructure
* to work with an IR.
* It will register the input/evdev interface for the device and
* register the syfs code for IR class
*/
int __ir_input_register(struct input_dev *input_dev,
const struct ir_scancode_table *rc_tab,
const struct ir_dev_props *props,
const char *driver_name)
{
struct ir_input_dev *ir_dev;
int rc;
if (rc_tab->scan == NULL || !rc_tab->size)
return -EINVAL;
ir_dev = kzalloc(sizeof(*ir_dev), GFP_KERNEL);
if (!ir_dev)
return -ENOMEM;
ir_dev->driver_name = kasprintf(GFP_KERNEL, "%s", driver_name);
if (!ir_dev->driver_name) {
rc = -ENOMEM;
goto out_dev;
}
input_dev->getkeycode = ir_getkeycode;
input_dev->setkeycode = ir_setkeycode;
input_set_drvdata(input_dev, ir_dev);
spin_lock_init(&ir_dev->rc_tab.lock);
ir_dev->rc_tab.name = rc_tab->name;
ir_dev->rc_tab.ir_type = rc_tab->ir_type;
ir_dev->rc_tab.alloc = roundup_pow_of_two(rc_tab->size *
sizeof(struct ir_scancode));
ir_dev->rc_tab.scan = kmalloc(ir_dev->rc_tab.alloc, GFP_KERNEL);
ir_dev->rc_tab.size = ir_dev->rc_tab.alloc / sizeof(struct ir_scancode);
if (!ir_dev->rc_tab.scan) {
rc = -ENOMEM;
goto out_name;
}
IR_dprintk(1, "Allocated space for %u keycode entries (%u bytes)\n",
ir_dev->rc_tab.size, ir_dev->rc_tab.alloc);
set_bit(EV_KEY, input_dev->evbit);
if (ir_setkeytable(input_dev, &ir_dev->rc_tab, rc_tab)) {
rc = -ENOMEM;
goto out_table;
}
ir_dev->props = props;
if (props && props->open)
input_dev->open = ir_open;
if (props && props->close)
input_dev->close = ir_close;
rc = ir_register_class(input_dev);
if (rc < 0)
goto out_table;
IR_dprintk(1, "Registered input device on %s for %s remote.\n",
driver_name, rc_tab->name);
return 0;
out_table:
kfree(ir_dev->rc_tab.scan);
out_name:
kfree(ir_dev->driver_name);
out_dev:
kfree(ir_dev);
return rc;
}
EXPORT_SYMBOL_GPL(__ir_input_register);
/**
* ir_input_unregister() - unregisters IR and frees resources
* @input_dev: the struct input_dev descriptor of the device
* This routine is used to free memory and de-register interfaces.
*/
void ir_input_unregister(struct input_dev *dev)
{
struct ir_input_dev *ir_dev = input_get_drvdata(dev);
struct ir_scancode_table *rc_tab;
if (!ir_dev)
return;
IR_dprintk(1, "Freed keycode table\n");
rc_tab = &ir_dev->rc_tab;
rc_tab->size = 0;
kfree(rc_tab->scan);
rc_tab->scan = NULL;
ir_unregister_class(dev);
kfree(ir_dev->driver_name);
kfree(ir_dev);
}
EXPORT_SYMBOL_GPL(ir_input_unregister);
int ir_core_debug; /* ir_debug level (0,1,2) */
EXPORT_SYMBOL_GPL(ir_core_debug);
module_param_named(debug, ir_core_debug, int, 0644);
MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
MODULE_LICENSE("GPL");
