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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Helpers for matrix keyboard bindings
4 *
5 * Copyright (C) 2012 Google, Inc
6 *
7 * Author:
8 * Olof Johansson <olof@lixom.net>
9 */
10
11#include <linux/device.h>
12#include <linux/export.h>
13#include <linux/gfp.h>
14#include <linux/input.h>
15#include <linux/input/matrix_keypad.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/property.h>
19#include <linux/slab.h>
20#include <linux/types.h>
21
22static bool matrix_keypad_map_key(struct input_dev *input_dev,
23 unsigned int rows, unsigned int cols,
24 unsigned int row_shift, unsigned int key)
25{
26 unsigned short *keymap = input_dev->keycode;
27 unsigned int row = KEY_ROW(key);
28 unsigned int col = KEY_COL(key);
29 unsigned short code = KEY_VAL(key);
30
31 if (row >= rows || col >= cols) {
32 dev_err(input_dev->dev.parent,
33 "%s: invalid keymap entry 0x%x (row: %d, col: %d, rows: %d, cols: %d)\n",
34 __func__, key, row, col, rows, cols);
35 return false;
36 }
37
38 keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
39 __set_bit(code, input_dev->keybit);
40
41 return true;
42}
43
44/**
45 * matrix_keypad_parse_properties() - Read properties of matrix keypad
46 *
47 * @dev: Device containing properties
48 * @rows: Returns number of matrix rows
49 * @cols: Returns number of matrix columns
50 * @return 0 if OK, <0 on error
51 */
52int matrix_keypad_parse_properties(struct device *dev,
53 unsigned int *rows, unsigned int *cols)
54{
55 *rows = *cols = 0;
56
57 device_property_read_u32(dev, "keypad,num-rows", rows);
58 device_property_read_u32(dev, "keypad,num-columns", cols);
59
60 if (!*rows || !*cols) {
61 dev_err(dev, "number of keypad rows/columns not specified\n");
62 return -EINVAL;
63 }
64
65 return 0;
66}
67EXPORT_SYMBOL_GPL(matrix_keypad_parse_properties);
68
69static int matrix_keypad_parse_keymap(const char *propname,
70 unsigned int rows, unsigned int cols,
71 struct input_dev *input_dev)
72{
73 struct device *dev = input_dev->dev.parent;
74 unsigned int row_shift = get_count_order(cols);
75 unsigned int max_keys = rows << row_shift;
76 u32 *keys;
77 int i;
78 int size;
79 int retval;
80
81 if (!propname)
82 propname = "linux,keymap";
83
84 size = device_property_count_u32(dev, propname);
85 if (size <= 0) {
86 dev_err(dev, "missing or malformed property %s: %d\n",
87 propname, size);
88 return size < 0 ? size : -EINVAL;
89 }
90
91 if (size > max_keys) {
92 dev_err(dev, "%s size overflow (%d vs max %u)\n",
93 propname, size, max_keys);
94 return -EINVAL;
95 }
96
97 keys = kmalloc_array(size, sizeof(u32), GFP_KERNEL);
98 if (!keys)
99 return -ENOMEM;
100
101 retval = device_property_read_u32_array(dev, propname, keys, size);
102 if (retval) {
103 dev_err(dev, "failed to read %s property: %d\n",
104 propname, retval);
105 goto out;
106 }
107
108 for (i = 0; i < size; i++) {
109 if (!matrix_keypad_map_key(input_dev, rows, cols,
110 row_shift, keys[i])) {
111 retval = -EINVAL;
112 goto out;
113 }
114 }
115
116 retval = 0;
117
118out:
119 kfree(keys);
120 return retval;
121}
122
123/**
124 * matrix_keypad_build_keymap - convert platform keymap into matrix keymap
125 * @keymap_data: keymap supplied by the platform code
126 * @keymap_name: name of device tree property containing keymap (if device
127 * tree support is enabled).
128 * @rows: number of rows in target keymap array
129 * @cols: number of cols in target keymap array
130 * @keymap: expanded version of keymap that is suitable for use by
131 * matrix keyboard driver
132 * @input_dev: input devices for which we are setting up the keymap
133 *
134 * This function converts platform keymap (encoded with KEY() macro) into
135 * an array of keycodes that is suitable for using in a standard matrix
136 * keyboard driver that uses row and col as indices.
137 *
138 * If @keymap_data is not supplied and device tree support is enabled
139 * it will attempt load the keymap from property specified by @keymap_name
140 * argument (or "linux,keymap" if @keymap_name is %NULL).
141 *
142 * If @keymap is %NULL the function will automatically allocate managed
143 * block of memory to store the keymap. This memory will be associated with
144 * the parent device and automatically freed when device unbinds from the
145 * driver.
146 *
147 * Callers are expected to set up input_dev->dev.parent before calling this
148 * function.
149 */
150int matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,
151 const char *keymap_name,
152 unsigned int rows, unsigned int cols,
153 unsigned short *keymap,
154 struct input_dev *input_dev)
155{
156 unsigned int row_shift = get_count_order(cols);
157 size_t max_keys = rows << row_shift;
158 int i;
159 int error;
160
161 if (WARN_ON(!input_dev->dev.parent))
162 return -EINVAL;
163
164 if (!keymap) {
165 keymap = devm_kcalloc(input_dev->dev.parent,
166 max_keys, sizeof(*keymap),
167 GFP_KERNEL);
168 if (!keymap) {
169 dev_err(input_dev->dev.parent,
170 "Unable to allocate memory for keymap");
171 return -ENOMEM;
172 }
173 }
174
175 input_dev->keycode = keymap;
176 input_dev->keycodesize = sizeof(*keymap);
177 input_dev->keycodemax = max_keys;
178
179 __set_bit(EV_KEY, input_dev->evbit);
180
181 if (keymap_data) {
182 for (i = 0; i < keymap_data->keymap_size; i++) {
183 unsigned int key = keymap_data->keymap[i];
184
185 if (!matrix_keypad_map_key(input_dev, rows, cols,
186 row_shift, key))
187 return -EINVAL;
188 }
189 } else {
190 error = matrix_keypad_parse_keymap(keymap_name, rows, cols,
191 input_dev);
192 if (error)
193 return error;
194 }
195
196 __clear_bit(KEY_RESERVED, input_dev->keybit);
197
198 return 0;
199}
200EXPORT_SYMBOL(matrix_keypad_build_keymap);
201
202MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Helpers for matrix keyboard bindings
4 *
5 * Copyright (C) 2012 Google, Inc
6 *
7 * Author:
8 * Olof Johansson <olof@lixom.net>
9 */
10
11#include <linux/device.h>
12#include <linux/export.h>
13#include <linux/gfp.h>
14#include <linux/input.h>
15#include <linux/input/matrix_keypad.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/property.h>
19#include <linux/slab.h>
20#include <linux/types.h>
21
22static bool matrix_keypad_map_key(struct input_dev *input_dev,
23 unsigned int rows, unsigned int cols,
24 unsigned int row_shift, unsigned int key)
25{
26 unsigned short *keymap = input_dev->keycode;
27 unsigned int row = KEY_ROW(key);
28 unsigned int col = KEY_COL(key);
29 unsigned short code = KEY_VAL(key);
30
31 if (row >= rows || col >= cols) {
32 dev_err(input_dev->dev.parent,
33 "%s: invalid keymap entry 0x%x (row: %d, col: %d, rows: %d, cols: %d)\n",
34 __func__, key, row, col, rows, cols);
35 return false;
36 }
37
38 keymap[MATRIX_SCAN_CODE(row, col, row_shift)] = code;
39 __set_bit(code, input_dev->keybit);
40
41 return true;
42}
43
44/**
45 * matrix_keypad_parse_properties() - Read properties of matrix keypad
46 *
47 * @dev: Device containing properties
48 * @rows: Returns number of matrix rows
49 * @cols: Returns number of matrix columns
50 * @return 0 if OK, <0 on error
51 */
52int matrix_keypad_parse_properties(struct device *dev,
53 unsigned int *rows, unsigned int *cols)
54{
55 *rows = *cols = 0;
56
57 device_property_read_u32(dev, "keypad,num-rows", rows);
58 device_property_read_u32(dev, "keypad,num-columns", cols);
59
60 if (!*rows || !*cols) {
61 dev_err(dev, "number of keypad rows/columns not specified\n");
62 return -EINVAL;
63 }
64
65 return 0;
66}
67EXPORT_SYMBOL_GPL(matrix_keypad_parse_properties);
68
69static int matrix_keypad_parse_keymap(const char *propname,
70 unsigned int rows, unsigned int cols,
71 struct input_dev *input_dev)
72{
73 struct device *dev = input_dev->dev.parent;
74 unsigned int row_shift = get_count_order(cols);
75 unsigned int max_keys = rows << row_shift;
76 u32 *keys;
77 int i;
78 int size;
79 int retval;
80
81 if (!propname)
82 propname = "linux,keymap";
83
84 size = device_property_count_u32(dev, propname);
85 if (size <= 0) {
86 dev_err(dev, "missing or malformed property %s: %d\n",
87 propname, size);
88 return size < 0 ? size : -EINVAL;
89 }
90
91 if (size > max_keys) {
92 dev_err(dev, "%s size overflow (%d vs max %u)\n",
93 propname, size, max_keys);
94 return -EINVAL;
95 }
96
97 keys = kmalloc_array(size, sizeof(u32), GFP_KERNEL);
98 if (!keys)
99 return -ENOMEM;
100
101 retval = device_property_read_u32_array(dev, propname, keys, size);
102 if (retval) {
103 dev_err(dev, "failed to read %s property: %d\n",
104 propname, retval);
105 goto out;
106 }
107
108 for (i = 0; i < size; i++) {
109 if (!matrix_keypad_map_key(input_dev, rows, cols,
110 row_shift, keys[i])) {
111 retval = -EINVAL;
112 goto out;
113 }
114 }
115
116 retval = 0;
117
118out:
119 kfree(keys);
120 return retval;
121}
122
123/**
124 * matrix_keypad_build_keymap - convert platform keymap into matrix keymap
125 * @keymap_data: keymap supplied by the platform code
126 * @keymap_name: name of device tree property containing keymap (if device
127 * tree support is enabled).
128 * @rows: number of rows in target keymap array
129 * @cols: number of cols in target keymap array
130 * @keymap: expanded version of keymap that is suitable for use by
131 * matrix keyboard driver
132 * @input_dev: input devices for which we are setting up the keymap
133 *
134 * This function converts platform keymap (encoded with KEY() macro) into
135 * an array of keycodes that is suitable for using in a standard matrix
136 * keyboard driver that uses row and col as indices.
137 *
138 * If @keymap_data is not supplied and device tree support is enabled
139 * it will attempt load the keymap from property specified by @keymap_name
140 * argument (or "linux,keymap" if @keymap_name is %NULL).
141 *
142 * If @keymap is %NULL the function will automatically allocate managed
143 * block of memory to store the keymap. This memory will be associated with
144 * the parent device and automatically freed when device unbinds from the
145 * driver.
146 *
147 * Callers are expected to set up input_dev->dev.parent before calling this
148 * function.
149 */
150int matrix_keypad_build_keymap(const struct matrix_keymap_data *keymap_data,
151 const char *keymap_name,
152 unsigned int rows, unsigned int cols,
153 unsigned short *keymap,
154 struct input_dev *input_dev)
155{
156 unsigned int row_shift = get_count_order(cols);
157 size_t max_keys = rows << row_shift;
158 int i;
159 int error;
160
161 if (WARN_ON(!input_dev->dev.parent))
162 return -EINVAL;
163
164 if (!keymap) {
165 keymap = devm_kcalloc(input_dev->dev.parent,
166 max_keys, sizeof(*keymap),
167 GFP_KERNEL);
168 if (!keymap) {
169 dev_err(input_dev->dev.parent,
170 "Unable to allocate memory for keymap");
171 return -ENOMEM;
172 }
173 }
174
175 input_dev->keycode = keymap;
176 input_dev->keycodesize = sizeof(*keymap);
177 input_dev->keycodemax = max_keys;
178
179 __set_bit(EV_KEY, input_dev->evbit);
180
181 if (keymap_data) {
182 for (i = 0; i < keymap_data->keymap_size; i++) {
183 unsigned int key = keymap_data->keymap[i];
184
185 if (!matrix_keypad_map_key(input_dev, rows, cols,
186 row_shift, key))
187 return -EINVAL;
188 }
189 } else {
190 error = matrix_keypad_parse_keymap(keymap_name, rows, cols,
191 input_dev);
192 if (error)
193 return error;
194 }
195
196 __clear_bit(KEY_RESERVED, input_dev->keybit);
197
198 return 0;
199}
200EXPORT_SYMBOL(matrix_keypad_build_keymap);
201
202MODULE_LICENSE("GPL");