1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) ST-Ericsson SA 2010
4 *
5 * Author: Rabin Vincent <rabin.vincent@stericsson.com> for ST-Ericsson
6 */
7
8 #include <linux/module.h>
9 #include <linux/slab.h>
10 #include <linux/input.h>
11 #include <linux/interrupt.h>
12 #include <linux/platform_device.h>
13 #include <linux/input/matrix_keypad.h>
14 #include <linux/mfd/stmpe.h>
15
16 /* These are at the same addresses in all STMPE variants */
17 #define STMPE_KPC_COL 0x60
18 #define STMPE_KPC_ROW_MSB 0x61
19 #define STMPE_KPC_ROW_LSB 0x62
20 #define STMPE_KPC_CTRL_MSB 0x63
21 #define STMPE_KPC_CTRL_LSB 0x64
22 #define STMPE_KPC_COMBI_KEY_0 0x65
23 #define STMPE_KPC_COMBI_KEY_1 0x66
24 #define STMPE_KPC_COMBI_KEY_2 0x67
25 #define STMPE_KPC_DATA_BYTE0 0x68
26 #define STMPE_KPC_DATA_BYTE1 0x69
27 #define STMPE_KPC_DATA_BYTE2 0x6a
28 #define STMPE_KPC_DATA_BYTE3 0x6b
29 #define STMPE_KPC_DATA_BYTE4 0x6c
30
31 #define STMPE_KPC_CTRL_LSB_SCAN (0x1 << 0)
32 #define STMPE_KPC_CTRL_LSB_DEBOUNCE (0x7f << 1)
33 #define STMPE_KPC_CTRL_MSB_SCAN_COUNT (0xf << 4)
34
35 #define STMPE_KPC_ROW_MSB_ROWS 0xff
36
37 #define STMPE_KPC_DATA_UP (0x1 << 7)
38 #define STMPE_KPC_DATA_ROW (0xf << 3)
39 #define STMPE_KPC_DATA_COL (0x7 << 0)
40 #define STMPE_KPC_DATA_NOKEY_MASK 0x78
41
42 #define STMPE_KEYPAD_MAX_DEBOUNCE 127
43 #define STMPE_KEYPAD_MAX_SCAN_COUNT 15
44
45 #define STMPE_KEYPAD_MAX_ROWS 8
46 #define STMPE_KEYPAD_MAX_COLS 8
47 #define STMPE_KEYPAD_ROW_SHIFT 3
48 #define STMPE_KEYPAD_KEYMAP_MAX_SIZE \
49 (STMPE_KEYPAD_MAX_ROWS * STMPE_KEYPAD_MAX_COLS)
50
51
52 #define STMPE1601_NUM_DATA 5
53 #define STMPE2401_NUM_DATA 3
54 #define STMPE2403_NUM_DATA 5
55
56 /* Make sure it covers all cases above */
57 #define MAX_NUM_DATA 5
58
59 /**
60 * struct stmpe_keypad_variant - model-specific attributes
61 * @auto_increment: whether the KPC_DATA_BYTE register address
62 * auto-increments on multiple read
63 * @set_pullup: whether the pins need to have their pull-ups set
64 * @num_data: number of data bytes
65 * @num_normal_data: number of normal keys' data bytes
66 * @max_cols: maximum number of columns supported
67 * @max_rows: maximum number of rows supported
68 * @col_gpios: bitmask of gpios which can be used for columns
69 * @row_gpios: bitmask of gpios which can be used for rows
70 */
71 struct stmpe_keypad_variant {
72 bool auto_increment;
73 bool set_pullup;
74 int num_data;
75 int num_normal_data;
76 int max_cols;
77 int max_rows;
78 unsigned int col_gpios;
79 unsigned int row_gpios;
80 };
81
82 static const struct stmpe_keypad_variant stmpe_keypad_variants[] = {
83 [STMPE1601] = {
84 .auto_increment = true,
85 .num_data = STMPE1601_NUM_DATA,
86 .num_normal_data = 3,
87 .max_cols = 8,
88 .max_rows = 8,
89 .col_gpios = 0x000ff, /* GPIO 0 - 7 */
90 .row_gpios = 0x0ff00, /* GPIO 8 - 15 */
91 },
92 [STMPE2401] = {
93 .auto_increment = false,
94 .set_pullup = true,
95 .num_data = STMPE2401_NUM_DATA,
96 .num_normal_data = 2,
97 .max_cols = 8,
98 .max_rows = 12,
99 .col_gpios = 0x0000ff, /* GPIO 0 - 7*/
100 .row_gpios = 0x1f7f00, /* GPIO 8-14, 16-20 */
101 },
102 [STMPE2403] = {
103 .auto_increment = true,
104 .set_pullup = true,
105 .num_data = STMPE2403_NUM_DATA,
106 .num_normal_data = 3,
107 .max_cols = 8,
108 .max_rows = 12,
109 .col_gpios = 0x0000ff, /* GPIO 0 - 7*/
110 .row_gpios = 0x1fef00, /* GPIO 8-14, 16-20 */
111 },
112 };
113
114 /**
115 * struct stmpe_keypad - STMPE keypad state container
116 * @stmpe: pointer to parent STMPE device
117 * @input: spawned input device
118 * @variant: STMPE variant
119 * @debounce_ms: debounce interval, in ms. Maximum is
120 * %STMPE_KEYPAD_MAX_DEBOUNCE.
121 * @scan_count: number of key scanning cycles to confirm key data.
122 * Maximum is %STMPE_KEYPAD_MAX_SCAN_COUNT.
123 * @no_autorepeat: disable key autorepeat
124 * @rows: bitmask for the rows
125 * @cols: bitmask for the columns
126 * @keymap: the keymap
127 */
128 struct stmpe_keypad {
129 struct stmpe *stmpe;
130 struct input_dev *input;
131 const struct stmpe_keypad_variant *variant;
132 unsigned int debounce_ms;
133 unsigned int scan_count;
134 bool no_autorepeat;
135 unsigned int rows;
136 unsigned int cols;
137 unsigned short keymap[STMPE_KEYPAD_KEYMAP_MAX_SIZE];
138 };
139
stmpe_keypad_read_data(struct stmpe_keypad * keypad,u8 * data)140 static int stmpe_keypad_read_data(struct stmpe_keypad *keypad, u8 *data)
141 {
142 const struct stmpe_keypad_variant *variant = keypad->variant;
143 struct stmpe *stmpe = keypad->stmpe;
144 int ret;
145 int i;
146
147 if (variant->auto_increment)
148 return stmpe_block_read(stmpe, STMPE_KPC_DATA_BYTE0,
149 variant->num_data, data);
150
151 for (i = 0; i < variant->num_data; i++) {
152 ret = stmpe_reg_read(stmpe, STMPE_KPC_DATA_BYTE0 + i);
153 if (ret < 0)
154 return ret;
155
156 data[i] = ret;
157 }
158
159 return 0;
160 }
161
stmpe_keypad_irq(int irq,void * dev)162 static irqreturn_t stmpe_keypad_irq(int irq, void *dev)
163 {
164 struct stmpe_keypad *keypad = dev;
165 struct input_dev *input = keypad->input;
166 const struct stmpe_keypad_variant *variant = keypad->variant;
167 u8 fifo[MAX_NUM_DATA];
168 int ret;
169 int i;
170
171 ret = stmpe_keypad_read_data(keypad, fifo);
172 if (ret < 0)
173 return IRQ_NONE;
174
175 for (i = 0; i < variant->num_normal_data; i++) {
176 u8 data = fifo[i];
177 int row = (data & STMPE_KPC_DATA_ROW) >> 3;
178 int col = data & STMPE_KPC_DATA_COL;
179 int code = MATRIX_SCAN_CODE(row, col, STMPE_KEYPAD_ROW_SHIFT);
180 bool up = data & STMPE_KPC_DATA_UP;
181
182 if ((data & STMPE_KPC_DATA_NOKEY_MASK)
183 == STMPE_KPC_DATA_NOKEY_MASK)
184 continue;
185
186 input_event(input, EV_MSC, MSC_SCAN, code);
187 input_report_key(input, keypad->keymap[code], !up);
188 input_sync(input);
189 }
190
191 return IRQ_HANDLED;
192 }
193
stmpe_keypad_altfunc_init(struct stmpe_keypad * keypad)194 static int stmpe_keypad_altfunc_init(struct stmpe_keypad *keypad)
195 {
196 const struct stmpe_keypad_variant *variant = keypad->variant;
197 unsigned int col_gpios = variant->col_gpios;
198 unsigned int row_gpios = variant->row_gpios;
199 struct stmpe *stmpe = keypad->stmpe;
200 u8 pureg = stmpe->regs[STMPE_IDX_GPPUR_LSB];
201 unsigned int pins = 0;
202 unsigned int pu_pins = 0;
203 int ret;
204 int i;
205
206 /*
207 * Figure out which pins need to be set to the keypad alternate
208 * function.
209 *
210 * {cols,rows}_gpios are bitmasks of which pins on the chip can be used
211 * for the keypad.
212 *
213 * keypad->{cols,rows} are a bitmask of which pins (of the ones useable
214 * for the keypad) are used on the board.
215 */
216
217 for (i = 0; i < variant->max_cols; i++) {
218 int num = __ffs(col_gpios);
219
220 if (keypad->cols & (1 << i)) {
221 pins |= 1 << num;
222 pu_pins |= 1 << num;
223 }
224
225 col_gpios &= ~(1 << num);
226 }
227
228 for (i = 0; i < variant->max_rows; i++) {
229 int num = __ffs(row_gpios);
230
231 if (keypad->rows & (1 << i))
232 pins |= 1 << num;
233
234 row_gpios &= ~(1 << num);
235 }
236
237 ret = stmpe_set_altfunc(stmpe, pins, STMPE_BLOCK_KEYPAD);
238 if (ret)
239 return ret;
240
241 /*
242 * On STMPE24xx, set pin bias to pull-up on all keypad input
243 * pins (columns), this incidentally happen to be maximum 8 pins
244 * and placed at GPIO0-7 so only the LSB of the pull up register
245 * ever needs to be written.
246 */
247 if (variant->set_pullup) {
248 u8 val;
249
250 ret = stmpe_reg_read(stmpe, pureg);
251 if (ret)
252 return ret;
253
254 /* Do not touch unused pins, may be used for GPIO */
255 val = ret & ~pu_pins;
256 val |= pu_pins;
257
258 ret = stmpe_reg_write(stmpe, pureg, val);
259 }
260
261 return 0;
262 }
263
stmpe_keypad_chip_init(struct stmpe_keypad * keypad)264 static int stmpe_keypad_chip_init(struct stmpe_keypad *keypad)
265 {
266 const struct stmpe_keypad_variant *variant = keypad->variant;
267 struct stmpe *stmpe = keypad->stmpe;
268 int ret;
269
270 if (keypad->debounce_ms > STMPE_KEYPAD_MAX_DEBOUNCE)
271 return -EINVAL;
272
273 if (keypad->scan_count > STMPE_KEYPAD_MAX_SCAN_COUNT)
274 return -EINVAL;
275
276 ret = stmpe_enable(stmpe, STMPE_BLOCK_KEYPAD);
277 if (ret < 0)
278 return ret;
279
280 ret = stmpe_keypad_altfunc_init(keypad);
281 if (ret < 0)
282 return ret;
283
284 ret = stmpe_reg_write(stmpe, STMPE_KPC_COL, keypad->cols);
285 if (ret < 0)
286 return ret;
287
288 ret = stmpe_reg_write(stmpe, STMPE_KPC_ROW_LSB, keypad->rows);
289 if (ret < 0)
290 return ret;
291
292 if (variant->max_rows > 8) {
293 ret = stmpe_set_bits(stmpe, STMPE_KPC_ROW_MSB,
294 STMPE_KPC_ROW_MSB_ROWS,
295 keypad->rows >> 8);
296 if (ret < 0)
297 return ret;
298 }
299
300 ret = stmpe_set_bits(stmpe, STMPE_KPC_CTRL_MSB,
301 STMPE_KPC_CTRL_MSB_SCAN_COUNT,
302 keypad->scan_count << 4);
303 if (ret < 0)
304 return ret;
305
306 return stmpe_set_bits(stmpe, STMPE_KPC_CTRL_LSB,
307 STMPE_KPC_CTRL_LSB_SCAN |
308 STMPE_KPC_CTRL_LSB_DEBOUNCE,
309 STMPE_KPC_CTRL_LSB_SCAN |
310 (keypad->debounce_ms << 1));
311 }
312
stmpe_keypad_fill_used_pins(struct stmpe_keypad * keypad,u32 used_rows,u32 used_cols)313 static void stmpe_keypad_fill_used_pins(struct stmpe_keypad *keypad,
314 u32 used_rows, u32 used_cols)
315 {
316 int row, col;
317
318 for (row = 0; row < used_rows; row++) {
319 for (col = 0; col < used_cols; col++) {
320 int code = MATRIX_SCAN_CODE(row, col,
321 STMPE_KEYPAD_ROW_SHIFT);
322 if (keypad->keymap[code] != KEY_RESERVED) {
323 keypad->rows |= 1 << row;
324 keypad->cols |= 1 << col;
325 }
326 }
327 }
328 }
329
stmpe_keypad_probe(struct platform_device * pdev)330 static int stmpe_keypad_probe(struct platform_device *pdev)
331 {
332 struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
333 struct device_node *np = pdev->dev.of_node;
334 struct stmpe_keypad *keypad;
335 struct input_dev *input;
336 u32 rows;
337 u32 cols;
338 int error;
339 int irq;
340
341 irq = platform_get_irq(pdev, 0);
342 if (irq < 0)
343 return irq;
344
345 keypad = devm_kzalloc(&pdev->dev, sizeof(struct stmpe_keypad),
346 GFP_KERNEL);
347 if (!keypad)
348 return -ENOMEM;
349
350 keypad->stmpe = stmpe;
351 keypad->variant = &stmpe_keypad_variants[stmpe->partnum];
352
353 of_property_read_u32(np, "debounce-interval", &keypad->debounce_ms);
354 of_property_read_u32(np, "st,scan-count", &keypad->scan_count);
355 keypad->no_autorepeat = of_property_read_bool(np, "st,no-autorepeat");
356
357 input = devm_input_allocate_device(&pdev->dev);
358 if (!input)
359 return -ENOMEM;
360
361 input->name = "STMPE keypad";
362 input->id.bustype = BUS_I2C;
363 input->dev.parent = &pdev->dev;
364
365 error = matrix_keypad_parse_properties(&pdev->dev, &rows, &cols);
366 if (error)
367 return error;
368
369 error = matrix_keypad_build_keymap(NULL, NULL, rows, cols,
370 keypad->keymap, input);
371 if (error)
372 return error;
373
374 input_set_capability(input, EV_MSC, MSC_SCAN);
375 if (!keypad->no_autorepeat)
376 __set_bit(EV_REP, input->evbit);
377
378 stmpe_keypad_fill_used_pins(keypad, rows, cols);
379
380 keypad->input = input;
381
382 error = stmpe_keypad_chip_init(keypad);
383 if (error < 0)
384 return error;
385
386 error = devm_request_threaded_irq(&pdev->dev, irq,
387 NULL, stmpe_keypad_irq,
388 IRQF_ONESHOT, "stmpe-keypad", keypad);
389 if (error) {
390 dev_err(&pdev->dev, "unable to get irq: %d\n", error);
391 return error;
392 }
393
394 error = input_register_device(input);
395 if (error) {
396 dev_err(&pdev->dev,
397 "unable to register input device: %d\n", error);
398 return error;
399 }
400
401 platform_set_drvdata(pdev, keypad);
402
403 return 0;
404 }
405
stmpe_keypad_remove(struct platform_device * pdev)406 static int stmpe_keypad_remove(struct platform_device *pdev)
407 {
408 struct stmpe_keypad *keypad = platform_get_drvdata(pdev);
409
410 stmpe_disable(keypad->stmpe, STMPE_BLOCK_KEYPAD);
411
412 return 0;
413 }
414
415 static struct platform_driver stmpe_keypad_driver = {
416 .driver.name = "stmpe-keypad",
417 .driver.owner = THIS_MODULE,
418 .probe = stmpe_keypad_probe,
419 .remove = stmpe_keypad_remove,
420 };
421 module_platform_driver(stmpe_keypad_driver);
422
423 MODULE_LICENSE("GPL v2");
424 MODULE_DESCRIPTION("STMPExxxx keypad driver");
425 MODULE_AUTHOR("Rabin Vincent <rabin.vincent@stericsson.com>");
426
