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/of.h>
13#include <linux/platform_device.h>
14#include <linux/input/matrix_keypad.h>
15#include <linux/mfd/stmpe.h>
16
17/* These are at the same addresses in all STMPE variants */
18#define STMPE_KPC_COL 0x60
19#define STMPE_KPC_ROW_MSB 0x61
20#define STMPE_KPC_ROW_LSB 0x62
21#define STMPE_KPC_CTRL_MSB 0x63
22#define STMPE_KPC_CTRL_LSB 0x64
23#define STMPE_KPC_COMBI_KEY_0 0x65
24#define STMPE_KPC_COMBI_KEY_1 0x66
25#define STMPE_KPC_COMBI_KEY_2 0x67
26#define STMPE_KPC_DATA_BYTE0 0x68
27#define STMPE_KPC_DATA_BYTE1 0x69
28#define STMPE_KPC_DATA_BYTE2 0x6a
29#define STMPE_KPC_DATA_BYTE3 0x6b
30#define STMPE_KPC_DATA_BYTE4 0x6c
31
32#define STMPE_KPC_CTRL_LSB_SCAN (0x1 << 0)
33#define STMPE_KPC_CTRL_LSB_DEBOUNCE (0x7f << 1)
34#define STMPE_KPC_CTRL_MSB_SCAN_COUNT (0xf << 4)
35
36#define STMPE_KPC_ROW_MSB_ROWS 0xff
37
38#define STMPE_KPC_DATA_UP (0x1 << 7)
39#define STMPE_KPC_DATA_ROW (0xf << 3)
40#define STMPE_KPC_DATA_COL (0x7 << 0)
41#define STMPE_KPC_DATA_NOKEY_MASK 0x78
42
43#define STMPE_KEYPAD_MAX_DEBOUNCE 127
44#define STMPE_KEYPAD_MAX_SCAN_COUNT 15
45
46#define STMPE_KEYPAD_MAX_ROWS 8
47#define STMPE_KEYPAD_MAX_COLS 8
48#define STMPE_KEYPAD_ROW_SHIFT 3
49#define STMPE_KEYPAD_KEYMAP_MAX_SIZE \
50 (STMPE_KEYPAD_MAX_ROWS * STMPE_KEYPAD_MAX_COLS)
51
52
53#define STMPE1601_NUM_DATA 5
54#define STMPE2401_NUM_DATA 3
55#define STMPE2403_NUM_DATA 5
56
57/* Make sure it covers all cases above */
58#define MAX_NUM_DATA 5
59
60/**
61 * struct stmpe_keypad_variant - model-specific attributes
62 * @auto_increment: whether the KPC_DATA_BYTE register address
63 * auto-increments on multiple read
64 * @set_pullup: whether the pins need to have their pull-ups set
65 * @num_data: number of data bytes
66 * @num_normal_data: number of normal keys' data bytes
67 * @max_cols: maximum number of columns supported
68 * @max_rows: maximum number of rows supported
69 * @col_gpios: bitmask of gpios which can be used for columns
70 * @row_gpios: bitmask of gpios which can be used for rows
71 */
72struct stmpe_keypad_variant {
73 bool auto_increment;
74 bool set_pullup;
75 int num_data;
76 int num_normal_data;
77 int max_cols;
78 int max_rows;
79 unsigned int col_gpios;
80 unsigned int row_gpios;
81};
82
83static const struct stmpe_keypad_variant stmpe_keypad_variants[] = {
84 [STMPE1601] = {
85 .auto_increment = true,
86 .num_data = STMPE1601_NUM_DATA,
87 .num_normal_data = 3,
88 .max_cols = 8,
89 .max_rows = 8,
90 .col_gpios = 0x000ff, /* GPIO 0 - 7 */
91 .row_gpios = 0x0ff00, /* GPIO 8 - 15 */
92 },
93 [STMPE2401] = {
94 .auto_increment = false,
95 .set_pullup = true,
96 .num_data = STMPE2401_NUM_DATA,
97 .num_normal_data = 2,
98 .max_cols = 8,
99 .max_rows = 12,
100 .col_gpios = 0x0000ff, /* GPIO 0 - 7*/
101 .row_gpios = 0x1f7f00, /* GPIO 8-14, 16-20 */
102 },
103 [STMPE2403] = {
104 .auto_increment = true,
105 .set_pullup = true,
106 .num_data = STMPE2403_NUM_DATA,
107 .num_normal_data = 3,
108 .max_cols = 8,
109 .max_rows = 12,
110 .col_gpios = 0x0000ff, /* GPIO 0 - 7*/
111 .row_gpios = 0x1fef00, /* GPIO 8-14, 16-20 */
112 },
113};
114
115/**
116 * struct stmpe_keypad - STMPE keypad state container
117 * @stmpe: pointer to parent STMPE device
118 * @input: spawned input device
119 * @variant: STMPE variant
120 * @debounce_ms: debounce interval, in ms. Maximum is
121 * %STMPE_KEYPAD_MAX_DEBOUNCE.
122 * @scan_count: number of key scanning cycles to confirm key data.
123 * Maximum is %STMPE_KEYPAD_MAX_SCAN_COUNT.
124 * @no_autorepeat: disable key autorepeat
125 * @rows: bitmask for the rows
126 * @cols: bitmask for the columns
127 * @keymap: the keymap
128 */
129struct stmpe_keypad {
130 struct stmpe *stmpe;
131 struct input_dev *input;
132 const struct stmpe_keypad_variant *variant;
133 unsigned int debounce_ms;
134 unsigned int scan_count;
135 bool no_autorepeat;
136 unsigned int rows;
137 unsigned int cols;
138 unsigned short keymap[STMPE_KEYPAD_KEYMAP_MAX_SIZE];
139};
140
141static int stmpe_keypad_read_data(struct stmpe_keypad *keypad, u8 *data)
142{
143 const struct stmpe_keypad_variant *variant = keypad->variant;
144 struct stmpe *stmpe = keypad->stmpe;
145 int ret;
146 int i;
147
148 if (variant->auto_increment)
149 return stmpe_block_read(stmpe, STMPE_KPC_DATA_BYTE0,
150 length: variant->num_data, values: data);
151
152 for (i = 0; i < variant->num_data; i++) {
153 ret = stmpe_reg_read(stmpe, STMPE_KPC_DATA_BYTE0 + i);
154 if (ret < 0)
155 return ret;
156
157 data[i] = ret;
158 }
159
160 return 0;
161}
162
163static irqreturn_t stmpe_keypad_irq(int irq, void *dev)
164{
165 struct stmpe_keypad *keypad = dev;
166 struct input_dev *input = keypad->input;
167 const struct stmpe_keypad_variant *variant = keypad->variant;
168 u8 fifo[MAX_NUM_DATA];
169 int ret;
170 int i;
171
172 ret = stmpe_keypad_read_data(keypad, data: fifo);
173 if (ret < 0)
174 return IRQ_NONE;
175
176 for (i = 0; i < variant->num_normal_data; i++) {
177 u8 data = fifo[i];
178 int row = (data & STMPE_KPC_DATA_ROW) >> 3;
179 int col = data & STMPE_KPC_DATA_COL;
180 int code = MATRIX_SCAN_CODE(row, col, STMPE_KEYPAD_ROW_SHIFT);
181 bool up = data & STMPE_KPC_DATA_UP;
182
183 if ((data & STMPE_KPC_DATA_NOKEY_MASK)
184 == STMPE_KPC_DATA_NOKEY_MASK)
185 continue;
186
187 input_event(dev: input, EV_MSC, MSC_SCAN, value: code);
188 input_report_key(dev: input, code: keypad->keymap[code], value: !up);
189 input_sync(dev: input);
190 }
191
192 return IRQ_HANDLED;
193}
194
195static int stmpe_keypad_altfunc_init(struct stmpe_keypad *keypad)
196{
197 const struct stmpe_keypad_variant *variant = keypad->variant;
198 unsigned int col_gpios = variant->col_gpios;
199 unsigned int row_gpios = variant->row_gpios;
200 struct stmpe *stmpe = keypad->stmpe;
201 u8 pureg = stmpe->regs[STMPE_IDX_GPPUR_LSB];
202 unsigned int pins = 0;
203 unsigned int pu_pins = 0;
204 int ret;
205 int i;
206
207 /*
208 * Figure out which pins need to be set to the keypad alternate
209 * function.
210 *
211 * {cols,rows}_gpios are bitmasks of which pins on the chip can be used
212 * for the keypad.
213 *
214 * keypad->{cols,rows} are a bitmask of which pins (of the ones useable
215 * for the keypad) are used on the board.
216 */
217
218 for (i = 0; i < variant->max_cols; i++) {
219 int num = __ffs(col_gpios);
220
221 if (keypad->cols & (1 << i)) {
222 pins |= 1 << num;
223 pu_pins |= 1 << num;
224 }
225
226 col_gpios &= ~(1 << num);
227 }
228
229 for (i = 0; i < variant->max_rows; i++) {
230 int num = __ffs(row_gpios);
231
232 if (keypad->rows & (1 << i))
233 pins |= 1 << num;
234
235 row_gpios &= ~(1 << num);
236 }
237
238 ret = stmpe_set_altfunc(stmpe, pins, block: STMPE_BLOCK_KEYPAD);
239 if (ret)
240 return ret;
241
242 /*
243 * On STMPE24xx, set pin bias to pull-up on all keypad input
244 * pins (columns), this incidentally happen to be maximum 8 pins
245 * and placed at GPIO0-7 so only the LSB of the pull up register
246 * ever needs to be written.
247 */
248 if (variant->set_pullup) {
249 u8 val;
250
251 ret = stmpe_reg_read(stmpe, reg: pureg);
252 if (ret)
253 return ret;
254
255 /* Do not touch unused pins, may be used for GPIO */
256 val = ret & ~pu_pins;
257 val |= pu_pins;
258
259 ret = stmpe_reg_write(stmpe, reg: pureg, data: val);
260 }
261
262 return 0;
263}
264
265static int stmpe_keypad_chip_init(struct stmpe_keypad *keypad)
266{
267 const struct stmpe_keypad_variant *variant = keypad->variant;
268 struct stmpe *stmpe = keypad->stmpe;
269 int ret;
270
271 if (keypad->debounce_ms > STMPE_KEYPAD_MAX_DEBOUNCE)
272 return -EINVAL;
273
274 if (keypad->scan_count > STMPE_KEYPAD_MAX_SCAN_COUNT)
275 return -EINVAL;
276
277 ret = stmpe_enable(stmpe, blocks: STMPE_BLOCK_KEYPAD);
278 if (ret < 0)
279 return ret;
280
281 ret = stmpe_keypad_altfunc_init(keypad);
282 if (ret < 0)
283 return ret;
284
285 ret = stmpe_reg_write(stmpe, STMPE_KPC_COL, data: keypad->cols);
286 if (ret < 0)
287 return ret;
288
289 ret = stmpe_reg_write(stmpe, STMPE_KPC_ROW_LSB, data: keypad->rows);
290 if (ret < 0)
291 return ret;
292
293 if (variant->max_rows > 8) {
294 ret = stmpe_set_bits(stmpe, STMPE_KPC_ROW_MSB,
295 STMPE_KPC_ROW_MSB_ROWS,
296 val: keypad->rows >> 8);
297 if (ret < 0)
298 return ret;
299 }
300
301 ret = stmpe_set_bits(stmpe, STMPE_KPC_CTRL_MSB,
302 STMPE_KPC_CTRL_MSB_SCAN_COUNT,
303 val: keypad->scan_count << 4);
304 if (ret < 0)
305 return ret;
306
307 return stmpe_set_bits(stmpe, STMPE_KPC_CTRL_LSB,
308 STMPE_KPC_CTRL_LSB_SCAN |
309 STMPE_KPC_CTRL_LSB_DEBOUNCE,
310 STMPE_KPC_CTRL_LSB_SCAN |
311 (keypad->debounce_ms << 1));
312}
313
314static void stmpe_keypad_fill_used_pins(struct stmpe_keypad *keypad,
315 u32 used_rows, u32 used_cols)
316{
317 int row, col;
318
319 for (row = 0; row < used_rows; row++) {
320 for (col = 0; col < used_cols; col++) {
321 int code = MATRIX_SCAN_CODE(row, col,
322 STMPE_KEYPAD_ROW_SHIFT);
323 if (keypad->keymap[code] != KEY_RESERVED) {
324 keypad->rows |= 1 << row;
325 keypad->cols |= 1 << col;
326 }
327 }
328 }
329}
330
331static int stmpe_keypad_probe(struct platform_device *pdev)
332{
333 struct stmpe *stmpe = dev_get_drvdata(dev: pdev->dev.parent);
334 struct device_node *np = pdev->dev.of_node;
335 struct stmpe_keypad *keypad;
336 struct input_dev *input;
337 u32 rows;
338 u32 cols;
339 int error;
340 int irq;
341
342 irq = platform_get_irq(pdev, 0);
343 if (irq < 0)
344 return irq;
345
346 keypad = devm_kzalloc(dev: &pdev->dev, size: sizeof(struct stmpe_keypad),
347 GFP_KERNEL);
348 if (!keypad)
349 return -ENOMEM;
350
351 keypad->stmpe = stmpe;
352 keypad->variant = &stmpe_keypad_variants[stmpe->partnum];
353
354 of_property_read_u32(np, propname: "debounce-interval", out_value: &keypad->debounce_ms);
355 of_property_read_u32(np, propname: "st,scan-count", out_value: &keypad->scan_count);
356 keypad->no_autorepeat = of_property_read_bool(np, propname: "st,no-autorepeat");
357
358 input = devm_input_allocate_device(&pdev->dev);
359 if (!input)
360 return -ENOMEM;
361
362 input->name = "STMPE keypad";
363 input->id.bustype = BUS_I2C;
364 input->dev.parent = &pdev->dev;
365
366 error = matrix_keypad_parse_properties(dev: &pdev->dev, rows: &rows, cols: &cols);
367 if (error)
368 return error;
369
370 error = matrix_keypad_build_keymap(NULL, NULL, rows, cols,
371 keymap: keypad->keymap, input_dev: input);
372 if (error)
373 return error;
374
375 input_set_capability(dev: input, EV_MSC, MSC_SCAN);
376 if (!keypad->no_autorepeat)
377 __set_bit(EV_REP, input->evbit);
378
379 stmpe_keypad_fill_used_pins(keypad, used_rows: rows, used_cols: cols);
380
381 keypad->input = input;
382
383 error = stmpe_keypad_chip_init(keypad);
384 if (error < 0)
385 return error;
386
387 error = devm_request_threaded_irq(dev: &pdev->dev, irq,
388 NULL, thread_fn: stmpe_keypad_irq,
389 IRQF_ONESHOT, devname: "stmpe-keypad", dev_id: keypad);
390 if (error) {
391 dev_err(&pdev->dev, "unable to get irq: %d\n", error);
392 return error;
393 }
394
395 error = input_register_device(input);
396 if (error) {
397 dev_err(&pdev->dev,
398 "unable to register input device: %d\n", error);
399 return error;
400 }
401
402 platform_set_drvdata(pdev, data: keypad);
403
404 return 0;
405}
406
407static int stmpe_keypad_remove(struct platform_device *pdev)
408{
409 struct stmpe_keypad *keypad = platform_get_drvdata(pdev);
410
411 stmpe_disable(stmpe: keypad->stmpe, blocks: STMPE_BLOCK_KEYPAD);
412
413 return 0;
414}
415
416static struct platform_driver stmpe_keypad_driver = {
417 .driver.name = "stmpe-keypad",
418 .driver.owner = THIS_MODULE,
419 .probe = stmpe_keypad_probe,
420 .remove = stmpe_keypad_remove,
421};
422module_platform_driver(stmpe_keypad_driver);
423
424MODULE_LICENSE("GPL v2");
425MODULE_DESCRIPTION("STMPExxxx keypad driver");
426MODULE_AUTHOR("Rabin Vincent <rabin.vincent@stericsson.com>");
427

source code of linux/drivers/input/keyboard/stmpe-keypad.c