19c92ab61SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only
21932811fSDmitry Torokhov /*
31932811fSDmitry Torokhov * Helpers for matrix keyboard bindings
41932811fSDmitry Torokhov *
51932811fSDmitry Torokhov * Copyright (C) 2012 Google, Inc
61932811fSDmitry Torokhov *
71932811fSDmitry Torokhov * Author:
81932811fSDmitry Torokhov * Olof Johansson <olof@lixom.net>
91932811fSDmitry Torokhov */
101932811fSDmitry Torokhov
11b45c8f35SDmitry Torokhov #include <linux/device.h>
121932811fSDmitry Torokhov #include <linux/export.h>
13aef01aadSDmitry Torokhov #include <linux/gfp.h>
14aef01aadSDmitry Torokhov #include <linux/input.h>
151932811fSDmitry Torokhov #include <linux/input/matrix_keypad.h>
16aef01aadSDmitry Torokhov #include <linux/kernel.h>
17aef01aadSDmitry Torokhov #include <linux/module.h>
18aef01aadSDmitry Torokhov #include <linux/property.h>
19aef01aadSDmitry Torokhov #include <linux/slab.h>
20aef01aadSDmitry Torokhov #include <linux/types.h>
211932811fSDmitry Torokhov
matrix_keypad_map_key(struct input_dev * input_dev,unsigned int rows,unsigned int cols,unsigned int row_shift,unsigned int key)22b45c8f35SDmitry Torokhov static bool matrix_keypad_map_key(struct input_dev *input_dev,
23b45c8f35SDmitry Torokhov unsigned int rows, unsigned int cols,
24b45c8f35SDmitry Torokhov unsigned int row_shift, unsigned int key)
25b45c8f35SDmitry Torokhov {
2686809173SDmitry Torokhov unsigned short *keymap = input_dev->keycode;
27b45c8f35SDmitry Torokhov unsigned int row = KEY_ROW(key);
28b45c8f35SDmitry Torokhov unsigned int col = KEY_COL(key);
29b45c8f35SDmitry Torokhov unsigned short code = KEY_VAL(key);
30b45c8f35SDmitry Torokhov
31b45c8f35SDmitry Torokhov if (row >= rows || col >= cols) {
32b45c8f35SDmitry Torokhov dev_err(input_dev->dev.parent,
33b45c8f35SDmitry Torokhov "%s: invalid keymap entry 0x%x (row: %d, col: %d, rows: %d, cols: %d)\n",
34b45c8f35SDmitry Torokhov __func__, key, row, col, rows, cols);
35b45c8f35SDmitry Torokhov return false;
36b45c8f35SDmitry Torokhov }
37b45c8f35SDmitry Torokhov
38b45c8f35SDmitry Torokhov keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
39b45c8f35SDmitry Torokhov __set_bit(code, input_dev->keybit);
40b45c8f35SDmitry Torokhov
41b45c8f35SDmitry Torokhov return true;
42b45c8f35SDmitry Torokhov }
43b45c8f35SDmitry Torokhov
44aef01aadSDmitry Torokhov /**
45aef01aadSDmitry Torokhov * matrix_keypad_parse_properties() - Read properties of matrix keypad
46aef01aadSDmitry Torokhov *
47aef01aadSDmitry Torokhov * @dev: Device containing properties
48aef01aadSDmitry Torokhov * @rows: Returns number of matrix rows
49aef01aadSDmitry Torokhov * @cols: Returns number of matrix columns
50aef01aadSDmitry Torokhov * @return 0 if OK, <0 on error
51aef01aadSDmitry Torokhov */
matrix_keypad_parse_properties(struct device * dev,unsigned int * rows,unsigned int * cols)52aef01aadSDmitry Torokhov int matrix_keypad_parse_properties(struct device *dev,
5343840415SSimon Glass unsigned int *rows, unsigned int *cols)
5443840415SSimon Glass {
55aef01aadSDmitry Torokhov *rows = *cols = 0;
5643840415SSimon Glass
57aef01aadSDmitry Torokhov device_property_read_u32(dev, "keypad,num-rows", rows);
58aef01aadSDmitry Torokhov device_property_read_u32(dev, "keypad,num-columns", cols);
59aef01aadSDmitry Torokhov
6043840415SSimon Glass if (!*rows || !*cols) {
6143840415SSimon Glass dev_err(dev, "number of keypad rows/columns not specified\n");
6243840415SSimon Glass return -EINVAL;
6343840415SSimon Glass }
6443840415SSimon Glass
6543840415SSimon Glass return 0;
6643840415SSimon Glass }
67aef01aadSDmitry Torokhov EXPORT_SYMBOL_GPL(matrix_keypad_parse_properties);
6843840415SSimon Glass
matrix_keypad_parse_keymap(const char * propname,unsigned int rows,unsigned int cols,struct input_dev * input_dev)69aef01aadSDmitry Torokhov static int matrix_keypad_parse_keymap(const char *propname,
70b45c8f35SDmitry Torokhov unsigned int rows, unsigned int cols,
71b45c8f35SDmitry Torokhov struct input_dev *input_dev)
72b45c8f35SDmitry Torokhov {
73b45c8f35SDmitry Torokhov struct device *dev = input_dev->dev.parent;
74b45c8f35SDmitry Torokhov unsigned int row_shift = get_count_order(cols);
75b45c8f35SDmitry Torokhov unsigned int max_keys = rows << row_shift;
76aef01aadSDmitry Torokhov u32 *keys;
77aef01aadSDmitry Torokhov int i;
78aef01aadSDmitry Torokhov int size;
79aef01aadSDmitry Torokhov int retval;
80b45c8f35SDmitry Torokhov
81b45c8f35SDmitry Torokhov if (!propname)
82b45c8f35SDmitry Torokhov propname = "linux,keymap";
83b45c8f35SDmitry Torokhov
84656d29ceSAndy Shevchenko size = device_property_count_u32(dev, propname);
85aef01aadSDmitry Torokhov if (size <= 0) {
86aef01aadSDmitry Torokhov dev_err(dev, "missing or malformed property %s: %d\n",
87aef01aadSDmitry Torokhov propname, size);
88aef01aadSDmitry Torokhov return size < 0 ? size : -EINVAL;
89b45c8f35SDmitry Torokhov }
90b45c8f35SDmitry Torokhov
91b45c8f35SDmitry Torokhov if (size > max_keys) {
92aef01aadSDmitry Torokhov dev_err(dev, "%s size overflow (%d vs max %u)\n",
93aef01aadSDmitry Torokhov propname, size, max_keys);
94b45c8f35SDmitry Torokhov return -EINVAL;
95b45c8f35SDmitry Torokhov }
96b45c8f35SDmitry Torokhov
97aef01aadSDmitry Torokhov keys = kmalloc_array(size, sizeof(u32), GFP_KERNEL);
98aef01aadSDmitry Torokhov if (!keys)
99aef01aadSDmitry Torokhov return -ENOMEM;
100aef01aadSDmitry Torokhov
101aef01aadSDmitry Torokhov retval = device_property_read_u32_array(dev, propname, keys, size);
102aef01aadSDmitry Torokhov if (retval) {
103aef01aadSDmitry Torokhov dev_err(dev, "failed to read %s property: %d\n",
104aef01aadSDmitry Torokhov propname, retval);
105aef01aadSDmitry Torokhov goto out;
106aef01aadSDmitry Torokhov }
107aef01aadSDmitry Torokhov
108b45c8f35SDmitry Torokhov for (i = 0; i < size; i++) {
109b45c8f35SDmitry Torokhov if (!matrix_keypad_map_key(input_dev, rows, cols,
110aef01aadSDmitry Torokhov row_shift, keys[i])) {
111aef01aadSDmitry Torokhov retval = -EINVAL;
112aef01aadSDmitry Torokhov goto out;
113aef01aadSDmitry Torokhov }
114b45c8f35SDmitry Torokhov }
115b45c8f35SDmitry Torokhov
116aef01aadSDmitry Torokhov retval = 0;
117aef01aadSDmitry Torokhov
118aef01aadSDmitry Torokhov out:
119aef01aadSDmitry Torokhov kfree(keys);
120aef01aadSDmitry Torokhov return retval;
121b45c8f35SDmitry Torokhov }
1221932811fSDmitry Torokhov
1231932811fSDmitry Torokhov /**
1241932811fSDmitry Torokhov * matrix_keypad_build_keymap - convert platform keymap into matrix keymap
1251932811fSDmitry Torokhov * @keymap_data: keymap supplied by the platform code
1261932811fSDmitry Torokhov * @keymap_name: name of device tree property containing keymap (if device
1271932811fSDmitry Torokhov * tree support is enabled).
1281932811fSDmitry Torokhov * @rows: number of rows in target keymap array
1291932811fSDmitry Torokhov * @cols: number of cols in target keymap array
1301932811fSDmitry Torokhov * @keymap: expanded version of keymap that is suitable for use by
1311932811fSDmitry Torokhov * matrix keyboard driver
1321932811fSDmitry Torokhov * @input_dev: input devices for which we are setting up the keymap
1331932811fSDmitry Torokhov *
1341932811fSDmitry Torokhov * This function converts platform keymap (encoded with KEY() macro) into
1351932811fSDmitry Torokhov * an array of keycodes that is suitable for using in a standard matrix
1361932811fSDmitry Torokhov * keyboard driver that uses row and col as indices.
137b45c8f35SDmitry Torokhov *
138b45c8f35SDmitry Torokhov * If @keymap_data is not supplied and device tree support is enabled
139b45c8f35SDmitry Torokhov * it will attempt load the keymap from property specified by @keymap_name
140b45c8f35SDmitry Torokhov * argument (or "linux,keymap" if @keymap_name is %NULL).
141b45c8f35SDmitry Torokhov *
1425383116bSDmitry Torokhov * If @keymap is %NULL the function will automatically allocate managed
1435383116bSDmitry Torokhov * block of memory to store the keymap. This memory will be associated with
1445383116bSDmitry Torokhov * the parent device and automatically freed when device unbinds from the
1455383116bSDmitry Torokhov * driver.
1465383116bSDmitry Torokhov *
147b45c8f35SDmitry Torokhov * Callers are expected to set up input_dev->dev.parent before calling this
148b45c8f35SDmitry Torokhov * function.
1491932811fSDmitry Torokhov */
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)1501932811fSDmitry Torokhov int matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,
1511932811fSDmitry Torokhov const char *keymap_name,
1521932811fSDmitry Torokhov unsigned int rows, unsigned int cols,
1531932811fSDmitry Torokhov unsigned short *keymap,
1541932811fSDmitry Torokhov struct input_dev *input_dev)
1551932811fSDmitry Torokhov {
1561932811fSDmitry Torokhov unsigned int row_shift = get_count_order(cols);
1575383116bSDmitry Torokhov size_t max_keys = rows << row_shift;
1581932811fSDmitry Torokhov int i;
159b45c8f35SDmitry Torokhov int error;
1601932811fSDmitry Torokhov
1615383116bSDmitry Torokhov if (WARN_ON(!input_dev->dev.parent))
1625383116bSDmitry Torokhov return -EINVAL;
1635383116bSDmitry Torokhov
1645383116bSDmitry Torokhov if (!keymap) {
165a86854d0SKees Cook keymap = devm_kcalloc(input_dev->dev.parent,
166a86854d0SKees Cook max_keys, sizeof(*keymap),
1675383116bSDmitry Torokhov GFP_KERNEL);
1685383116bSDmitry Torokhov if (!keymap) {
1695383116bSDmitry Torokhov dev_err(input_dev->dev.parent,
1705383116bSDmitry Torokhov "Unable to allocate memory for keymap");
1715383116bSDmitry Torokhov return -ENOMEM;
1725383116bSDmitry Torokhov }
1735383116bSDmitry Torokhov }
1745383116bSDmitry Torokhov
1751932811fSDmitry Torokhov input_dev->keycode = keymap;
1761932811fSDmitry Torokhov input_dev->keycodesize = sizeof(*keymap);
1775383116bSDmitry Torokhov input_dev->keycodemax = max_keys;
1781932811fSDmitry Torokhov
1791932811fSDmitry Torokhov __set_bit(EV_KEY, input_dev->evbit);
1801932811fSDmitry Torokhov
181b45c8f35SDmitry Torokhov if (keymap_data) {
1821932811fSDmitry Torokhov for (i = 0; i < keymap_data->keymap_size; i++) {
1831932811fSDmitry Torokhov unsigned int key = keymap_data->keymap[i];
1841932811fSDmitry Torokhov
185b45c8f35SDmitry Torokhov if (!matrix_keypad_map_key(input_dev, rows, cols,
186b45c8f35SDmitry Torokhov row_shift, key))
1871932811fSDmitry Torokhov return -EINVAL;
1881932811fSDmitry Torokhov }
189b45c8f35SDmitry Torokhov } else {
190aef01aadSDmitry Torokhov error = matrix_keypad_parse_keymap(keymap_name, rows, cols,
191b45c8f35SDmitry Torokhov input_dev);
192b45c8f35SDmitry Torokhov if (error)
193b45c8f35SDmitry Torokhov return error;
1941932811fSDmitry Torokhov }
195b45c8f35SDmitry Torokhov
1961932811fSDmitry Torokhov __clear_bit(KEY_RESERVED, input_dev->keybit);
1971932811fSDmitry Torokhov
1981932811fSDmitry Torokhov return 0;
1991932811fSDmitry Torokhov }
2001932811fSDmitry Torokhov EXPORT_SYMBOL(matrix_keypad_build_keymap);
201516d798fSFlorian Fainelli
202*e17fb91cSJeff Johnson MODULE_DESCRIPTION("Helpers for matrix keyboard bindings");
203516d798fSFlorian Fainelli MODULE_LICENSE("GPL");
204