tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright 2025 Bootlin
4 *
5 * Author: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
6 */
7
8#include <linux/bitfield.h>
9#include <linux/bitops.h>
10#include <linux/dev_printk.h>
11#include <linux/device/devres.h>
12#include <linux/err.h>
13#include <linux/init.h>
14#include <linux/input.h>
15#include <linux/input/matrix_keypad.h>
16#include <linux/interrupt.h>
17#include <linux/mfd/max7360.h>
18#include <linux/mod_devicetable.h>
19#include <linux/minmax.h>
20#include <linux/module.h>
21#include <linux/property.h>
22#include <linux/platform_device.h>
23#include <linux/pm_wakeirq.h>
24#include <linux/regmap.h>
25
26struct max7360_keypad {
27 struct input_dev *input;
28 unsigned int rows;
29 unsigned int cols;
30 unsigned int debounce_ms;
31 int irq;
32 struct regmap *regmap;
33 unsigned short keycodes[MAX7360_MAX_KEY_ROWS * MAX7360_MAX_KEY_COLS];
34};
35
36static irqreturn_t max7360_keypad_irq(int irq, void *data)
37{
38 struct max7360_keypad *max7360_keypad = data;
39 struct device *dev = max7360_keypad->input->dev.parent;
40 unsigned int val;
41 unsigned int row, col;
42 unsigned int release;
43 unsigned int code;
44 int error;
45
46 error = regmap_read(max7360_keypad->regmap, MAX7360_REG_KEYFIFO, &val);
47 if (error) {
48 dev_err(dev, "Failed to read MAX7360 FIFO");
49 return IRQ_NONE;
50 }
51
52 /* FIFO overflow: ignore it and get next event. */
53 if (val == MAX7360_FIFO_OVERFLOW) {
54 dev_warn(dev, "max7360 FIFO overflow");
55 error = regmap_read_poll_timeout(max7360_keypad->regmap, MAX7360_REG_KEYFIFO,
56 val, val != MAX7360_FIFO_OVERFLOW, 0, 1000);
57 if (error) {
58 dev_err(dev, "Failed to empty MAX7360 FIFO");
59 return IRQ_NONE;
60 }
61 }
62
63 if (val == MAX7360_FIFO_EMPTY) {
64 dev_dbg(dev, "Got a spurious interrupt");
65
66 return IRQ_NONE;
67 }
68
69 row = FIELD_GET(MAX7360_FIFO_ROW, val);
70 col = FIELD_GET(MAX7360_FIFO_COL, val);
71 release = val & MAX7360_FIFO_RELEASE;
72
73 code = MATRIX_SCAN_CODE(row, col, get_count_order(max7360_keypad->cols));
74
75 dev_dbg(dev, "key[%d:%d] %s\n", row, col, release ? "release" : "press");
76
77 input_event(max7360_keypad->input, EV_MSC, MSC_SCAN, code);
78 input_report_key(max7360_keypad->input, max7360_keypad->keycodes[code], !release);
79 input_sync(max7360_keypad->input);
80
81 return IRQ_HANDLED;
82}
83
84static int max7360_keypad_open(struct input_dev *pdev)
85{
86 struct max7360_keypad *max7360_keypad = input_get_drvdata(pdev);
87 struct device *dev = max7360_keypad->input->dev.parent;
88 int error;
89
90 /* Somebody is using the device: get out of sleep. */
91 error = regmap_write_bits(max7360_keypad->regmap, MAX7360_REG_CONFIG,
92 MAX7360_CFG_SLEEP, MAX7360_CFG_SLEEP);
93 if (error)
94 dev_err(dev, "Failed to write max7360 configuration: %d\n", error);
95
96 return error;
97}
98
99static void max7360_keypad_close(struct input_dev *pdev)
100{
101 struct max7360_keypad *max7360_keypad = input_get_drvdata(pdev);
102 struct device *dev = max7360_keypad->input->dev.parent;
103 int error;
104
105 /* Nobody is using the device anymore: go to sleep. */
106 error = regmap_write_bits(max7360_keypad->regmap, MAX7360_REG_CONFIG, MAX7360_CFG_SLEEP, 0);
107 if (error)
108 dev_err(dev, "Failed to write max7360 configuration: %d\n", error);
109}
110
111static int max7360_keypad_hw_init(struct max7360_keypad *max7360_keypad)
112{
113 struct device *dev = max7360_keypad->input->dev.parent;
114 unsigned int val;
115 int error;
116
117 val = max7360_keypad->debounce_ms - MAX7360_DEBOUNCE_MIN;
118 error = regmap_write_bits(max7360_keypad->regmap, MAX7360_REG_DEBOUNCE,
119 MAX7360_DEBOUNCE,
120 FIELD_PREP(MAX7360_DEBOUNCE, val));
121 if (error)
122 return dev_err_probe(dev, error,
123 "Failed to write max7360 debounce configuration\n");
124
125 error = regmap_write_bits(max7360_keypad->regmap, MAX7360_REG_INTERRUPT,
126 MAX7360_INTERRUPT_TIME_MASK,
127 FIELD_PREP(MAX7360_INTERRUPT_TIME_MASK, 1));
128 if (error)
129 return dev_err_probe(dev, error,
130 "Failed to write max7360 keypad interrupt configuration\n");
131
132 return 0;
133}
134
135static int max7360_keypad_build_keymap(struct max7360_keypad *max7360_keypad)
136{
137 struct input_dev *input_dev = max7360_keypad->input;
138 struct device *dev = input_dev->dev.parent->parent;
139 struct matrix_keymap_data keymap_data;
140 const char *propname = "linux,keymap";
141 unsigned int max_keys;
142 int error;
143 int size;
144
145 size = device_property_count_u32(dev, propname);
146 if (size <= 0) {
147 dev_err(dev, "missing or malformed property %s: %d\n", propname, size);
148 return size < 0 ? size : -EINVAL;
149 }
150
151 max_keys = max7360_keypad->cols * max7360_keypad->rows;
152 if (size > max_keys) {
153 dev_err(dev, "%s size overflow (%d vs max %u)\n", propname, size, max_keys);
154 return -EINVAL;
155 }
156
157 u32 *keys __free(kfree) = kmalloc_array(size, sizeof(*keys), GFP_KERNEL);
158 if (!keys)
159 return -ENOMEM;
160
161 error = device_property_read_u32_array(dev, propname, keys, size);
162 if (error) {
163 dev_err(dev, "failed to read %s property: %d\n", propname, error);
164 return error;
165 }
166
167 keymap_data.keymap = keys;
168 keymap_data.keymap_size = size;
169 error = matrix_keypad_build_keymap(&keymap_data, NULL,
170 max7360_keypad->rows, max7360_keypad->cols,
171 max7360_keypad->keycodes, max7360_keypad->input);
172 if (error)
173 return error;
174
175 return 0;
176}
177
178static int max7360_keypad_parse_fw(struct device *dev,
179 struct max7360_keypad *max7360_keypad,
180 bool *autorepeat)
181{
182 int error;
183
184 error = matrix_keypad_parse_properties(dev->parent, &max7360_keypad->rows,
185 &max7360_keypad->cols);
186 if (error)
187 return error;
188
189 if (!max7360_keypad->rows || !max7360_keypad->cols ||
190 max7360_keypad->rows > MAX7360_MAX_KEY_ROWS ||
191 max7360_keypad->cols > MAX7360_MAX_KEY_COLS) {
192 dev_err(dev, "Invalid number of columns or rows (%ux%u)\n",
193 max7360_keypad->cols, max7360_keypad->rows);
194 return -EINVAL;
195 }
196
197 *autorepeat = device_property_read_bool(dev->parent, "autorepeat");
198
199 max7360_keypad->debounce_ms = MAX7360_DEBOUNCE_MIN;
200 error = device_property_read_u32(dev->parent, "keypad-debounce-delay-ms",
201 &max7360_keypad->debounce_ms);
202 if (error == -EINVAL) {
203 dev_info(dev, "Using default keypad-debounce-delay-ms: %u\n",
204 max7360_keypad->debounce_ms);
205 } else if (error < 0) {
206 dev_err(dev, "Failed to read keypad-debounce-delay-ms property\n");
207 return error;
208 }
209
210 if (!in_range(max7360_keypad->debounce_ms, MAX7360_DEBOUNCE_MIN,
211 MAX7360_DEBOUNCE_MAX - MAX7360_DEBOUNCE_MIN + 1)) {
212 dev_err(dev, "Invalid keypad-debounce-delay-ms: %u, should be between %u and %u.\n",
213 max7360_keypad->debounce_ms, MAX7360_DEBOUNCE_MIN, MAX7360_DEBOUNCE_MAX);
214 return -EINVAL;
215 }
216
217 return 0;
218}
219
220static int max7360_keypad_probe(struct platform_device *pdev)
221{
222 struct max7360_keypad *max7360_keypad;
223 struct device *dev = &pdev->dev;
224 struct input_dev *input;
225 struct regmap *regmap;
226 bool autorepeat;
227 int error;
228 int irq;
229
230 regmap = dev_get_regmap(dev->parent, NULL);
231 if (!regmap)
232 return dev_err_probe(dev, -ENODEV, "Could not get parent regmap\n");
233
234 irq = fwnode_irq_get_byname(dev_fwnode(dev->parent), "intk");
235 if (irq < 0)
236 return dev_err_probe(dev, irq, "Failed to get IRQ\n");
237
238 max7360_keypad = devm_kzalloc(dev, sizeof(*max7360_keypad), GFP_KERNEL);
239 if (!max7360_keypad)
240 return -ENOMEM;
241
242 max7360_keypad->regmap = regmap;
243
244 error = max7360_keypad_parse_fw(dev, max7360_keypad, &autorepeat);
245 if (error)
246 return error;
247
248 input = devm_input_allocate_device(dev);
249 if (!input)
250 return -ENOMEM;
251
252 max7360_keypad->input = input;
253
254 input->id.bustype = BUS_I2C;
255 input->name = pdev->name;
256 input->open = max7360_keypad_open;
257 input->close = max7360_keypad_close;
258
259 error = max7360_keypad_build_keymap(max7360_keypad);
260 if (error)
261 return dev_err_probe(dev, error, "Failed to build keymap\n");
262
263 input_set_capability(input, EV_MSC, MSC_SCAN);
264 if (autorepeat)
265 __set_bit(EV_REP, input->evbit);
266
267 input_set_drvdata(input, max7360_keypad);
268
269 error = devm_request_threaded_irq(dev, irq, NULL, max7360_keypad_irq,
270 IRQF_ONESHOT,
271 "max7360-keypad", max7360_keypad);
272 if (error)
273 return dev_err_probe(dev, error, "Failed to register interrupt\n");
274
275 error = input_register_device(input);
276 if (error)
277 return dev_err_probe(dev, error, "Could not register input device\n");
278
279 error = max7360_keypad_hw_init(max7360_keypad);
280 if (error)
281 return dev_err_probe(dev, error, "Failed to initialize max7360 keypad\n");
282
283 device_init_wakeup(dev, true);
284 error = dev_pm_set_wake_irq(dev, irq);
285 if (error)
286 dev_warn(dev, "Failed to set up wakeup irq: %d\n", error);
287
288 return 0;
289}
290
291static void max7360_keypad_remove(struct platform_device *pdev)
292{
293 dev_pm_clear_wake_irq(&pdev->dev);
294 device_init_wakeup(&pdev->dev, false);
295}
296
297static struct platform_driver max7360_keypad_driver = {
298 .driver = {
299 .name = "max7360-keypad",
300 },
301 .probe = max7360_keypad_probe,
302 .remove = max7360_keypad_remove,
303};
304module_platform_driver(max7360_keypad_driver);
305
306MODULE_DESCRIPTION("MAX7360 Keypad driver");
307MODULE_AUTHOR("Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>");
308MODULE_LICENSE("GPL");