/*
* 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/device.h>
#include <linux/gfp.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/input.h>
#include <linux/of.h>
#include <linux/export.h>
#include <linux/module.h>
#include <linux/input/matrix_keypad.h>
static bool matrix_keypad_map_key(struct input_dev *input_dev,
unsigned int rows, unsigned int cols,
unsigned int row_shift, unsigned int key)
{
unsigned short *keymap = input_dev->keycode;
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 0x%x (row: %d, col: %d, rows: %d, cols: %d)\n",
__func__, key, row, col, rows, cols);
return false;
}
keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
__set_bit(code, input_dev->keybit);
return true;
}
#ifdef CONFIG_OF
int matrix_keypad_parse_of_params(struct device *dev,
unsigned int *rows, unsigned int *cols)
{
struct device_node *np = dev->of_node;
if (!np) {
dev_err(dev, "missing DT data");
return -EINVAL;
}
of_property_read_u32(np, "keypad,num-rows", rows);
of_property_read_u32(np, "keypad,num-columns", cols);
if (!*rows || !*cols) {
dev_err(dev, "number of keypad rows/columns not specified\n");
return -EINVAL;
}
return 0;
}
EXPORT_SYMBOL_GPL(matrix_keypad_parse_of_params);
static int matrix_keypad_parse_of_keymap(const char *propname,
unsigned int rows, unsigned int cols,
struct input_dev *input_dev)
{
struct device *dev = input_dev->dev.parent;
struct device_node *np = dev->of_node;
unsigned int row_shift = get_count_order(cols);
unsigned int max_keys = rows << row_shift;
unsigned int proplen, i, size;
const __be32 *prop;
if (!np)
return -ENOENT;
if (!propname)
propname = "linux,keymap";
prop = of_get_property(np, propname, &proplen);
if (!prop) {
dev_err(dev, "OF: %s property not defined in %s\n",
propname, np->full_name);
return -ENOENT;
}
if (proplen % sizeof(u32)) {
dev_err(dev, "OF: Malformed keycode property %s in %s\n",
propname, np->full_name);
return -EINVAL;
}
size = proplen / sizeof(u32);
if (size > max_keys) {
dev_err(dev, "OF: %s size overflow\n", propname);
return -EINVAL;
}
for (i = 0; i < size; i++) {
unsigned int key = be32_to_cpup(prop + i);
if (!matrix_keypad_map_key(input_dev, rows, cols,
row_shift, key))
return -EINVAL;
}
return 0;
}
#else
static int matrix_keypad_parse_of_keymap(const char *propname,
unsigned int rows, unsigned int cols,
struct input_dev *input_dev)
{
return -ENOSYS;
}
#endif
/**
* 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.
*
* If @keymap_data is not supplied and device tree support is enabled
* it will attempt load the keymap from property specified by @keymap_name
* argument (or "linux,keymap" if @keymap_name is %NULL).
*
* If @keymap is %NULL the function will automatically allocate managed
* block of memory to store the keymap. This memory will be associated with
* the parent device and automatically freed when device unbinds from the
* driver.
*
* Callers are expected to set up input_dev->dev.parent before calling this
* function.
*/
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);
size_t max_keys = rows << row_shift;
int i;
int error;
if (WARN_ON(!input_dev->dev.parent))
return -EINVAL;
if (!keymap) {
keymap = devm_kzalloc(input_dev->dev.parent,
max_keys * sizeof(*keymap),
GFP_KERNEL);
if (!keymap) {
dev_err(input_dev->dev.parent,
"Unable to allocate memory for keymap");
return -ENOMEM;
}
}
input_dev->keycode = keymap;
input_dev->keycodesize = sizeof(*keymap);
input_dev->keycodemax = max_keys;
__set_bit(EV_KEY, input_dev->evbit);
if (keymap_data) {
for (i = 0; i < keymap_data->keymap_size; i++) {
unsigned int key = keymap_data->keymap[i];
if (!matrix_keypad_map_key(input_dev, rows, cols,
row_shift, key))
return -EINVAL;
}
} else {
error = matrix_keypad_parse_of_keymap(keymap_name, rows, cols,
input_dev);
if (error)
return error;
}
__clear_bit(KEY_RESERVED, input_dev->keybit);
return 0;
}
EXPORT_SYMBOL(matrix_keypad_build_keymap);
MODULE_LICENSE("GPL");
