/*
* Helpers for matrix keyboard bindings
*
* Copyright (C) 2012 Google, Inc
*
* Author:
* Olof Johansson <olof@lixom.net>
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* 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/kernel.h>
#include <linux/types.h>
#include <linux/input.h>
#include <linux/of.h>
#include <linux/export.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/input/matrix_keypad.h>
/**
* matrix_keypad_build_keymap - convert platform keymap into matrix keymap
* @keymap_data: keymap supplied by the platform code
* @keymap_name: name of device tree property containing keymap (if device
* tree support is enabled).
* @rows: number of rows in target keymap array
* @cols: number of cols in target keymap array
* @keymap: expanded version of keymap that is suitable for use by
* matrix keyboard driver
* @input_dev: input devices for which we are setting up the keymap
*
* This function converts platform keymap (encoded with KEY() macro) into
* an array of keycodes that is suitable for using in a standard matrix
* keyboard driver that uses row and col as indices.
*/
int matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,
const char *keymap_name,
unsigned int rows, unsigned int cols,
unsigned short *keymap,
struct input_dev *input_dev)
{
unsigned int row_shift = get_count_order(cols);
int i;
input_dev->keycode = keymap;
input_dev->keycodesize = sizeof(*keymap);
input_dev->keycodemax = rows << row_shift;
__set_bit(EV_KEY, input_dev->evbit);
for (i = 0; i < keymap_data->keymap_size; i++) {
unsigned int key = keymap_data->keymap[i];
unsigned int row = KEY_ROW(key);
unsigned int col = KEY_COL(key);
unsigned short code = KEY_VAL(key);
if (row >= rows || col >= cols) {
dev_err(input_dev->dev.parent,
"%s: invalid keymap entry %d (row: %d, col: %d, rows: %d, cols: %d)\n",
__func__, i, row, col, rows, cols);
return -EINVAL;
}
keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
__set_bit(code, input_dev->keybit);
}
__clear_bit(KEY_RESERVED, input_dev->keybit);
return 0;
}
EXPORT_SYMBOL(matrix_keypad_build_keymap);
#ifdef CONFIG_OF
struct matrix_keymap_data *
matrix_keyboard_of_fill_keymap(struct device_node *np,
const char *propname)
{
struct matrix_keymap_data *kd;
u32 *keymap;
int proplen, i;
const __be32 *prop;
if (!np)
return NULL;
if (!propname)
propname = "linux,keymap";
prop = of_get_property(np, propname, &proplen);
if (!prop)
return NULL;
if (proplen % sizeof(u32)) {
pr_warn("Malformed keymap property %s in %s\n",
propname, np->full_name);
return NULL;
}
kd = kzalloc(sizeof(*kd), GFP_KERNEL);
if (!kd)
return NULL;
kd->keymap = keymap = kzalloc(proplen, GFP_KERNEL);
if (!kd->keymap) {
kfree(kd);
return NULL;
}
kd->keymap_size = proplen / sizeof(u32);
for (i = 0; i < kd->keymap_size; i++) {
u32 tmp = be32_to_cpup(prop + i);
int key_code, row, col;
row = (tmp >> 24) & 0xff;
col = (tmp >> 16) & 0xff;
key_code = tmp & 0xffff;
keymap[i] = KEY(row, col, key_code);
}
return kd;
}
EXPORT_SYMBOL_GPL(matrix_keyboard_of_fill_keymap);
void matrix_keyboard_of_free_keymap(const struct matrix_keymap_data *kd)
{
if (kd) {
kfree(kd->keymap);
kfree(kd);
}
}
EXPORT_SYMBOL_GPL(matrix_keyboard_of_free_keymap);
#endif
