1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Analog Devices ADP5585 Keys driver
4 *
5 * Copyright (C) 2025 Analog Devices, Inc.
6 */
7
8 #include <linux/bitmap.h>
9 #include <linux/container_of.h>
10 #include <linux/device.h>
11 #include <linux/find.h>
12 #include <linux/input.h>
13 #include <linux/input/matrix_keypad.h>
14 #include <linux/mfd/adp5585.h>
15 #include <linux/module.h>
16 #include <linux/mod_devicetable.h>
17 #include <linux/notifier.h>
18 #include <linux/platform_device.h>
19 #include <linux/property.h>
20 #include <linux/regmap.h>
21 #include <linux/types.h>
22
23 /* As needed for the matrix parsing code */
24 #define ADP5589_MAX_KEYMAPSIZE 123
25
26 struct adp5585_kpad_chip {
27 u8 key_ev_min;
28 u8 key_ev_max;
29 u8 max_rows;
30 u8 max_cols;
31 };
32
33 struct adp5585_kpad {
34 const struct adp5585_kpad_chip *info;
35 struct notifier_block nb;
36 struct input_dev *input;
37 unsigned short keycode[ADP5589_MAX_KEYMAPSIZE];
38 struct device *dev;
39 unsigned long keypad;
40 int row_shift;
41 };
42
adp5585_keys_validate_events(const struct adp5585_kpad * kpad,const u32 * events,u32 n_events)43 static int adp5585_keys_validate_events(const struct adp5585_kpad *kpad,
44 const u32 *events, u32 n_events)
45 {
46 unsigned int ev;
47 u32 row, col;
48
49 for (ev = 0; ev < n_events; ev++) {
50 if (events[ev] < kpad->info->key_ev_min ||
51 events[ev] > kpad->info->key_ev_max)
52 continue;
53
54 /*
55 * if the event is to be generated by the keymap, we need to make
56 * sure that the pins are part of it!
57 */
58 row = (events[ev] - 1) / kpad->info->max_cols;
59 col = (events[ev] - 1) % kpad->info->max_cols;
60
61 if (test_bit(row, &kpad->keypad) &&
62 test_bit(col + kpad->info->max_rows, &kpad->keypad))
63 continue;
64
65 return dev_err_probe(kpad->dev, -EINVAL,
66 "Invalid unlock/reset event(%u) not used in the keypad\n",
67 events[ev]);
68 }
69
70 return 0;
71 }
72
adp5585_keys_check_special_events(const struct adp5585_dev * adp5585,const struct adp5585_kpad * kpad)73 static int adp5585_keys_check_special_events(const struct adp5585_dev *adp5585,
74 const struct adp5585_kpad *kpad)
75 {
76 int error;
77
78 error = adp5585_keys_validate_events(kpad, adp5585->unlock_keys,
79 adp5585->nkeys_unlock);
80 if (error)
81 return error;
82
83 error = adp5585_keys_validate_events(kpad, adp5585->reset1_keys,
84 adp5585->nkeys_reset1);
85 if (error)
86 return error;
87
88 return adp5585_keys_validate_events(kpad, adp5585->reset2_keys,
89 adp5585->nkeys_reset2);
90 }
91
adp5585_keys_pins_free(void * data)92 static void adp5585_keys_pins_free(void *data)
93 {
94 struct adp5585_kpad *kpad = data;
95 struct adp5585_dev *adp5585 = dev_get_drvdata(kpad->dev->parent);
96 unsigned int pin;
97
98 for_each_set_bit(pin, &kpad->keypad, adp5585->n_pins)
99 clear_bit(pin, adp5585->pin_usage);
100 }
101
adp5585_keys_parse_fw(const struct adp5585_dev * adp5585,struct adp5585_kpad * kpad)102 static int adp5585_keys_parse_fw(const struct adp5585_dev *adp5585,
103 struct adp5585_kpad *kpad)
104 {
105 struct device *dev = kpad->dev;
106 u32 cols = 0, rows = 0, pin;
107 int error, n_pins;
108
109 /*
110 * We do not check for errors (or no value) since the input device is
111 * only added if this property is present in the first place.
112 */
113 n_pins = device_property_count_u32(dev, "adi,keypad-pins");
114 if (n_pins > adp5585->n_pins)
115 return dev_err_probe(dev, -EINVAL,
116 "Too many keypad pins (%d) defined (max=%d)\n",
117 n_pins, adp5585->n_pins);
118
119 unsigned int *keypad_pins __free(kfree) = kcalloc(n_pins, sizeof(*keypad_pins),
120 GFP_KERNEL);
121 if (!keypad_pins)
122 return -ENOMEM;
123
124 error = device_property_read_u32_array(dev, "adi,keypad-pins",
125 keypad_pins, n_pins);
126 if (error)
127 return error;
128
129 /*
130 * We can add the action here since it makes the code easier and nothing
131 * "bad" will happen out of it. Worst case, it will be a no-op and no
132 * bit will set.
133 */
134 error = devm_add_action_or_reset(dev, adp5585_keys_pins_free, kpad);
135 if (error)
136 return error;
137
138 for (pin = 0; pin < n_pins; pin++) {
139 if (keypad_pins[pin] >= adp5585->n_pins)
140 return dev_err_probe(dev, -EINVAL,
141 "Invalid keypad pin(%u) defined\n",
142 keypad_pins[pin]);
143
144 if (test_and_set_bit(keypad_pins[pin], adp5585->pin_usage))
145 return dev_err_probe(dev, -EBUSY,
146 "Keypad pin(%u) already used\n",
147 keypad_pins[pin]);
148
149 __set_bit(keypad_pins[pin], &kpad->keypad);
150 }
151
152 /*
153 * Note that given that we get a mask (and the HW allows it), we
154 * can have holes in our keypad (eg: row0, row1 and row7 enabled).
155 * However, for the matrix parsing functions we need to pass the
156 * number of rows/cols as the maximum row/col used plus 1. This
157 * pretty much means we will also have holes in our SW keypad.
158 */
159
160 rows = find_last_bit(&kpad->keypad, kpad->info->max_rows) + 1;
161 if (rows == kpad->info->max_rows + 1)
162 return dev_err_probe(dev, -EINVAL,
163 "Now rows defined in the keypad!\n");
164
165 cols = find_last_bit(&kpad->keypad, kpad->info->max_cols + kpad->info->max_rows);
166 if (cols < kpad->info->max_rows)
167 return dev_err_probe(dev, -EINVAL,
168 "No columns defined in the keypad!\n");
169
170 cols = cols + 1 - kpad->info->max_rows;
171
172 error = matrix_keypad_build_keymap(NULL, NULL, rows, cols,
173 kpad->keycode, kpad->input);
174 if (error)
175 return error;
176
177 kpad->row_shift = get_count_order(cols);
178
179 if (device_property_read_bool(kpad->dev, "autorepeat"))
180 __set_bit(EV_REP, kpad->input->evbit);
181
182 error = adp5585_keys_check_special_events(adp5585, kpad);
183 if (error)
184 return error;
185
186 return 0;
187 }
188
adp5585_keys_setup(const struct adp5585_dev * adp5585,struct adp5585_kpad * kpad)189 static int adp5585_keys_setup(const struct adp5585_dev *adp5585,
190 struct adp5585_kpad *kpad)
191 {
192 unsigned long keys_bits, start = 0, nbits = kpad->info->max_rows;
193 const struct adp5585_regs *regs = adp5585->regs;
194 unsigned int i = 0, max_cols = kpad->info->max_cols;
195 int error;
196
197 /*
198 * Take care as the below assumes max_rows is always less or equal than
199 * 8 which is true for the supported devices. If we happen to add
200 * another device we need to make sure this still holds true. Although
201 * adding a new device is very unlikely.
202 */
203 do {
204 keys_bits = bitmap_read(&kpad->keypad, start, nbits);
205 if (keys_bits) {
206 error = regmap_write(adp5585->regmap, regs->pin_cfg_a + i,
207 keys_bits);
208 if (error)
209 return error;
210 }
211
212 start += nbits;
213 if (max_cols > 8) {
214 nbits = 8;
215 max_cols -= nbits;
216 } else {
217 nbits = max_cols;
218 }
219
220 i++;
221 } while (start < kpad->info->max_rows + kpad->info->max_cols);
222
223 return 0;
224 }
225
adp5585_keys_ev_handle(struct notifier_block * nb,unsigned long key,void * data)226 static int adp5585_keys_ev_handle(struct notifier_block *nb, unsigned long key,
227 void *data)
228 {
229 struct adp5585_kpad *kpad = container_of(nb, struct adp5585_kpad, nb);
230 unsigned long key_press = (unsigned long)data;
231 unsigned int row, col, code;
232
233 /* make sure the event is for us */
234 if (key < kpad->info->key_ev_min || key > kpad->info->key_ev_max)
235 return NOTIFY_DONE;
236
237 /*
238 * Unlikely but lets be on the safe side! We do not return any error
239 * because the event was indeed for us but with some weird value. So,
240 * we still want the caller know that the right handler was called.
241 */
242 if (!key)
243 return NOTIFY_BAD;
244
245 row = (key - 1) / (kpad->info->max_cols);
246 col = (key - 1) % (kpad->info->max_cols);
247 code = MATRIX_SCAN_CODE(row, col, kpad->row_shift);
248
249 dev_dbg_ratelimited(kpad->dev, "report key(%lu) r(%d) c(%d) code(%d)\n",
250 key, row, col, kpad->keycode[code]);
251
252 input_report_key(kpad->input, kpad->keycode[code], key_press);
253 input_sync(kpad->input);
254
255 return NOTIFY_STOP;
256 }
257
adp5585_keys_unreg_notifier(void * data)258 static void adp5585_keys_unreg_notifier(void *data)
259 {
260 struct adp5585_kpad *kpad = data;
261 struct adp5585_dev *adp5585 = dev_get_drvdata(kpad->dev->parent);
262
263 blocking_notifier_chain_unregister(&adp5585->event_notifier,
264 &kpad->nb);
265 }
266
adp5585_keys_probe(struct platform_device * pdev)267 static int adp5585_keys_probe(struct platform_device *pdev)
268 {
269 const struct platform_device_id *id = platform_get_device_id(pdev);
270 struct adp5585_dev *adp5585 = dev_get_drvdata(pdev->dev.parent);
271 struct device *dev = &pdev->dev;
272 struct adp5585_kpad *kpad;
273 unsigned int revid;
274 const char *phys;
275 int error;
276
277 kpad = devm_kzalloc(dev, sizeof(*kpad), GFP_KERNEL);
278 if (!kpad)
279 return -ENOMEM;
280
281 if (!adp5585->irq)
282 return dev_err_probe(dev, -EINVAL,
283 "IRQ is mandatory for the keypad\n");
284
285 kpad->dev = dev;
286
287 kpad->input = devm_input_allocate_device(dev);
288 if (!kpad->input)
289 return -ENOMEM;
290
291 kpad->info = (const struct adp5585_kpad_chip *)id->driver_data;
292 if (!kpad->info)
293 return -ENODEV;
294
295 error = regmap_read(adp5585->regmap, ADP5585_ID, &revid);
296 if (error)
297 return dev_err_probe(dev, error, "Failed to read device ID\n");
298
299 phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input0", pdev->name);
300 if (!phys)
301 return -ENOMEM;
302
303 kpad->input->name = pdev->name;
304 kpad->input->phys = phys;
305
306 kpad->input->id.bustype = BUS_I2C;
307 kpad->input->id.vendor = 0x0001;
308 kpad->input->id.product = 0x0001;
309 kpad->input->id.version = revid & ADP5585_REV_ID_MASK;
310
311 device_set_of_node_from_dev(dev, dev->parent);
312
313 error = adp5585_keys_parse_fw(adp5585, kpad);
314 if (error)
315 return error;
316
317 error = adp5585_keys_setup(adp5585, kpad);
318 if (error)
319 return error;
320
321 kpad->nb.notifier_call = adp5585_keys_ev_handle;
322 error = blocking_notifier_chain_register(&adp5585->event_notifier,
323 &kpad->nb);
324 if (error)
325 return error;
326
327 error = devm_add_action_or_reset(dev, adp5585_keys_unreg_notifier, kpad);
328 if (error)
329 return error;
330
331 error = input_register_device(kpad->input);
332 if (error)
333 return dev_err_probe(dev, error,
334 "Failed to register input device\n");
335
336 return 0;
337 }
338
339 static const struct adp5585_kpad_chip adp5585_kpad_chip_info = {
340 .max_rows = 6,
341 .max_cols = 5,
342 .key_ev_min = ADP5585_ROW5_KEY_EVENT_START,
343 .key_ev_max = ADP5585_ROW5_KEY_EVENT_END,
344 };
345
346 static const struct adp5585_kpad_chip adp5589_kpad_chip_info = {
347 .max_rows = 8,
348 .max_cols = 11,
349 .key_ev_min = ADP5589_KEY_EVENT_START,
350 .key_ev_max = ADP5589_KEY_EVENT_END,
351 };
352
353 static const struct platform_device_id adp5585_keys_id_table[] = {
354 { "adp5585-keys", (kernel_ulong_t)&adp5585_kpad_chip_info },
355 { "adp5589-keys", (kernel_ulong_t)&adp5589_kpad_chip_info },
356 { }
357 };
358 MODULE_DEVICE_TABLE(platform, adp5585_keys_id_table);
359
360 static struct platform_driver adp5585_keys_driver = {
361 .driver = {
362 .name = "adp5585-keys",
363 },
364 .probe = adp5585_keys_probe,
365 .id_table = adp5585_keys_id_table,
366 };
367 module_platform_driver(adp5585_keys_driver);
368
369 MODULE_AUTHOR("Nuno Sá <nuno.sa@analog.com>");
370 MODULE_DESCRIPTION("ADP5585 Keys Driver");
371 MODULE_LICENSE("GPL");
372