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David Brownell9d834062009-08-25 19:24:14 -07001/*
2 * twl4030_keypad.c - driver for 8x8 keypad controller in twl4030 chips
3 *
4 * Copyright (C) 2007 Texas Instruments, Inc.
5 * Copyright (C) 2008 Nokia Corporation
6 *
7 * Code re-written for 2430SDP by:
8 * Syed Mohammed Khasim <x0khasim@ti.com>
9 *
10 * Initial Code:
11 * Manjunatha G K <manjugk@ti.com>
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
17 *
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
22 *
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 */
27
28#include <linux/kernel.h>
29#include <linux/module.h>
30#include <linux/init.h>
31#include <linux/interrupt.h>
32#include <linux/input.h>
33#include <linux/platform_device.h>
Santosh Shilimkarb07682b2009-12-13 20:05:51 +010034#include <linux/i2c/twl.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090035#include <linux/slab.h>
David Brownell9d834062009-08-25 19:24:14 -070036
37
38/*
39 * The TWL4030 family chips include a keypad controller that supports
40 * up to an 8x8 switch matrix. The controller can issue system wakeup
41 * events, since it uses only the always-on 32KiHz oscillator, and has
42 * an internal state machine that decodes pressed keys, including
43 * multi-key combinations.
44 *
45 * This driver lets boards define what keycodes they wish to report for
46 * which scancodes, as part of the "struct twl4030_keypad_data" used in
47 * the probe() routine.
48 *
49 * See the TPS65950 documentation; that's the general availability
50 * version of the TWL5030 second generation part.
51 */
52#define TWL4030_MAX_ROWS 8 /* TWL4030 hard limit */
53#define TWL4030_MAX_COLS 8
Dmitry Torokhov3fea6022010-07-20 20:25:35 -070054/*
55 * Note that we add space for an extra column so that we can handle
56 * row lines connected to the gnd (see twl4030_col_xlate()).
57 */
58#define TWL4030_ROW_SHIFT 4
59#define TWL4030_KEYMAP_SIZE (TWL4030_MAX_ROWS << TWL4030_ROW_SHIFT)
David Brownell9d834062009-08-25 19:24:14 -070060
61struct twl4030_keypad {
62 unsigned short keymap[TWL4030_KEYMAP_SIZE];
63 u16 kp_state[TWL4030_MAX_ROWS];
64 unsigned n_rows;
65 unsigned n_cols;
66 unsigned irq;
67
68 struct device *dbg_dev;
69 struct input_dev *input;
70};
71
72/*----------------------------------------------------------------------*/
73
74/* arbitrary prescaler value 0..7 */
75#define PTV_PRESCALER 4
76
77/* Register Offsets */
78#define KEYP_CTRL 0x00
79#define KEYP_DEB 0x01
80#define KEYP_LONG_KEY 0x02
81#define KEYP_LK_PTV 0x03
82#define KEYP_TIMEOUT_L 0x04
83#define KEYP_TIMEOUT_H 0x05
84#define KEYP_KBC 0x06
85#define KEYP_KBR 0x07
86#define KEYP_SMS 0x08
87#define KEYP_FULL_CODE_7_0 0x09 /* row 0 column status */
88#define KEYP_FULL_CODE_15_8 0x0a /* ... row 1 ... */
89#define KEYP_FULL_CODE_23_16 0x0b
90#define KEYP_FULL_CODE_31_24 0x0c
91#define KEYP_FULL_CODE_39_32 0x0d
92#define KEYP_FULL_CODE_47_40 0x0e
93#define KEYP_FULL_CODE_55_48 0x0f
94#define KEYP_FULL_CODE_63_56 0x10
95#define KEYP_ISR1 0x11
96#define KEYP_IMR1 0x12
97#define KEYP_ISR2 0x13
98#define KEYP_IMR2 0x14
99#define KEYP_SIR 0x15
100#define KEYP_EDR 0x16 /* edge triggers */
101#define KEYP_SIH_CTRL 0x17
102
103/* KEYP_CTRL_REG Fields */
104#define KEYP_CTRL_SOFT_NRST BIT(0)
105#define KEYP_CTRL_SOFTMODEN BIT(1)
106#define KEYP_CTRL_LK_EN BIT(2)
107#define KEYP_CTRL_TOE_EN BIT(3)
108#define KEYP_CTRL_TOLE_EN BIT(4)
109#define KEYP_CTRL_RP_EN BIT(5)
110#define KEYP_CTRL_KBD_ON BIT(6)
111
112/* KEYP_DEB, KEYP_LONG_KEY, KEYP_TIMEOUT_x*/
113#define KEYP_PERIOD_US(t, prescale) ((t) / (31 << (prescale + 1)) - 1)
114
115/* KEYP_LK_PTV_REG Fields */
116#define KEYP_LK_PTV_PTV_SHIFT 5
117
118/* KEYP_{IMR,ISR,SIR} Fields */
119#define KEYP_IMR1_MIS BIT(3)
120#define KEYP_IMR1_TO BIT(2)
121#define KEYP_IMR1_LK BIT(1)
122#define KEYP_IMR1_KP BIT(0)
123
124/* KEYP_EDR Fields */
125#define KEYP_EDR_KP_FALLING 0x01
126#define KEYP_EDR_KP_RISING 0x02
127#define KEYP_EDR_KP_BOTH 0x03
128#define KEYP_EDR_LK_FALLING 0x04
129#define KEYP_EDR_LK_RISING 0x08
130#define KEYP_EDR_TO_FALLING 0x10
131#define KEYP_EDR_TO_RISING 0x20
132#define KEYP_EDR_MIS_FALLING 0x40
133#define KEYP_EDR_MIS_RISING 0x80
134
135
136/*----------------------------------------------------------------------*/
137
138static int twl4030_kpread(struct twl4030_keypad *kp,
139 u8 *data, u32 reg, u8 num_bytes)
140{
Balaji T Kfc7b92f2009-12-13 21:23:33 +0100141 int ret = twl_i2c_read(TWL4030_MODULE_KEYPAD, data, reg, num_bytes);
David Brownell9d834062009-08-25 19:24:14 -0700142
143 if (ret < 0)
144 dev_warn(kp->dbg_dev,
145 "Couldn't read TWL4030: %X - ret %d[%x]\n",
146 reg, ret, ret);
147
148 return ret;
149}
150
151static int twl4030_kpwrite_u8(struct twl4030_keypad *kp, u8 data, u32 reg)
152{
Balaji T Kfc7b92f2009-12-13 21:23:33 +0100153 int ret = twl_i2c_write_u8(TWL4030_MODULE_KEYPAD, data, reg);
David Brownell9d834062009-08-25 19:24:14 -0700154
155 if (ret < 0)
156 dev_warn(kp->dbg_dev,
157 "Could not write TWL4030: %X - ret %d[%x]\n",
158 reg, ret, ret);
159
160 return ret;
161}
162
163static inline u16 twl4030_col_xlate(struct twl4030_keypad *kp, u8 col)
164{
165 /* If all bits in a row are active for all coloumns then
166 * we have that row line connected to gnd. Mark this
167 * key on as if it was on matrix position n_cols (ie
168 * one higher than the size of the matrix).
169 */
170 if (col == 0xFF)
171 return 1 << kp->n_cols;
172 else
173 return col & ((1 << kp->n_cols) - 1);
174}
175
176static int twl4030_read_kp_matrix_state(struct twl4030_keypad *kp, u16 *state)
177{
178 u8 new_state[TWL4030_MAX_ROWS];
179 int row;
180 int ret = twl4030_kpread(kp, new_state,
181 KEYP_FULL_CODE_7_0, kp->n_rows);
182 if (ret >= 0)
183 for (row = 0; row < kp->n_rows; row++)
184 state[row] = twl4030_col_xlate(kp, new_state[row]);
185
186 return ret;
187}
188
Dmitry Torokhov3fea6022010-07-20 20:25:35 -0700189static bool twl4030_is_in_ghost_state(struct twl4030_keypad *kp, u16 *key_state)
David Brownell9d834062009-08-25 19:24:14 -0700190{
191 int i;
192 u16 check = 0;
193
194 for (i = 0; i < kp->n_rows; i++) {
195 u16 col = key_state[i];
196
197 if ((col & check) && hweight16(col) > 1)
Dmitry Torokhov3fea6022010-07-20 20:25:35 -0700198 return true;
David Brownell9d834062009-08-25 19:24:14 -0700199
200 check |= col;
201 }
202
Dmitry Torokhov3fea6022010-07-20 20:25:35 -0700203 return false;
David Brownell9d834062009-08-25 19:24:14 -0700204}
205
206static void twl4030_kp_scan(struct twl4030_keypad *kp, bool release_all)
207{
208 struct input_dev *input = kp->input;
209 u16 new_state[TWL4030_MAX_ROWS];
210 int col, row;
211
212 if (release_all)
213 memset(new_state, 0, sizeof(new_state));
214 else {
215 /* check for any changes */
216 int ret = twl4030_read_kp_matrix_state(kp, new_state);
217
218 if (ret < 0) /* panic ... */
219 return;
220
221 if (twl4030_is_in_ghost_state(kp, new_state))
222 return;
223 }
224
225 /* check for changes and print those */
226 for (row = 0; row < kp->n_rows; row++) {
227 int changed = new_state[row] ^ kp->kp_state[row];
228
229 if (!changed)
230 continue;
231
Dmitry Torokhov3fea6022010-07-20 20:25:35 -0700232 /* Extra column handles "all gnd" rows */
233 for (col = 0; col < kp->n_cols + 1; col++) {
David Brownell9d834062009-08-25 19:24:14 -0700234 int code;
235
236 if (!(changed & (1 << col)))
237 continue;
238
239 dev_dbg(kp->dbg_dev, "key [%d:%d] %s\n", row, col,
240 (new_state[row] & (1 << col)) ?
241 "press" : "release");
242
243 code = MATRIX_SCAN_CODE(row, col, TWL4030_ROW_SHIFT);
244 input_event(input, EV_MSC, MSC_SCAN, code);
245 input_report_key(input, kp->keymap[code],
246 new_state[row] & (1 << col));
247 }
248 kp->kp_state[row] = new_state[row];
249 }
250 input_sync(input);
251}
252
253/*
254 * Keypad interrupt handler
255 */
256static irqreturn_t do_kp_irq(int irq, void *_kp)
257{
258 struct twl4030_keypad *kp = _kp;
259 u8 reg;
260 int ret;
261
David Brownell9d834062009-08-25 19:24:14 -0700262 /* Read & Clear TWL4030 pending interrupt */
263 ret = twl4030_kpread(kp, &reg, KEYP_ISR1, 1);
264
265 /* Release all keys if I2C has gone bad or
266 * the KEYP has gone to idle state */
267 if (ret >= 0 && (reg & KEYP_IMR1_KP))
268 twl4030_kp_scan(kp, false);
269 else
270 twl4030_kp_scan(kp, true);
271
272 return IRQ_HANDLED;
273}
274
275static int __devinit twl4030_kp_program(struct twl4030_keypad *kp)
276{
277 u8 reg;
278 int i;
279
280 /* Enable controller, with hardware decoding but not autorepeat */
281 reg = KEYP_CTRL_SOFT_NRST | KEYP_CTRL_SOFTMODEN
282 | KEYP_CTRL_TOE_EN | KEYP_CTRL_KBD_ON;
283 if (twl4030_kpwrite_u8(kp, reg, KEYP_CTRL) < 0)
284 return -EIO;
285
286 /* NOTE: we could use sih_setup() here to package keypad
287 * event sources as four different IRQs ... but we don't.
288 */
289
290 /* Enable TO rising and KP rising and falling edge detection */
291 reg = KEYP_EDR_KP_BOTH | KEYP_EDR_TO_RISING;
292 if (twl4030_kpwrite_u8(kp, reg, KEYP_EDR) < 0)
293 return -EIO;
294
295 /* Set PTV prescaler Field */
296 reg = (PTV_PRESCALER << KEYP_LK_PTV_PTV_SHIFT);
297 if (twl4030_kpwrite_u8(kp, reg, KEYP_LK_PTV) < 0)
298 return -EIO;
299
300 /* Set key debounce time to 20 ms */
301 i = KEYP_PERIOD_US(20000, PTV_PRESCALER);
302 if (twl4030_kpwrite_u8(kp, i, KEYP_DEB) < 0)
303 return -EIO;
304
305 /* Set timeout period to 100 ms */
306 i = KEYP_PERIOD_US(200000, PTV_PRESCALER);
307 if (twl4030_kpwrite_u8(kp, (i & 0xFF), KEYP_TIMEOUT_L) < 0)
308 return -EIO;
309
310 if (twl4030_kpwrite_u8(kp, (i >> 8), KEYP_TIMEOUT_H) < 0)
311 return -EIO;
312
313 /*
314 * Enable Clear-on-Read; disable remembering events that fire
315 * after the IRQ but before our handler acks (reads) them,
316 */
317 reg = TWL4030_SIH_CTRL_COR_MASK | TWL4030_SIH_CTRL_PENDDIS_MASK;
318 if (twl4030_kpwrite_u8(kp, reg, KEYP_SIH_CTRL) < 0)
319 return -EIO;
320
321 /* initialize key state; irqs update it from here on */
322 if (twl4030_read_kp_matrix_state(kp, kp->kp_state) < 0)
323 return -EIO;
324
325 return 0;
326}
327
328/*
329 * Registers keypad device with input subsystem
330 * and configures TWL4030 keypad registers
331 */
332static int __devinit twl4030_kp_probe(struct platform_device *pdev)
333{
334 struct twl4030_keypad_data *pdata = pdev->dev.platform_data;
335 const struct matrix_keymap_data *keymap_data = pdata->keymap_data;
336 struct twl4030_keypad *kp;
337 struct input_dev *input;
338 u8 reg;
339 int error;
340
341 if (!pdata || !pdata->rows || !pdata->cols ||
342 pdata->rows > TWL4030_MAX_ROWS || pdata->cols > TWL4030_MAX_COLS) {
343 dev_err(&pdev->dev, "Invalid platform_data\n");
344 return -EINVAL;
345 }
346
347 kp = kzalloc(sizeof(*kp), GFP_KERNEL);
348 input = input_allocate_device();
349 if (!kp || !input) {
350 error = -ENOMEM;
351 goto err1;
352 }
353
354 /* Get the debug Device */
355 kp->dbg_dev = &pdev->dev;
356 kp->input = input;
357
358 kp->n_rows = pdata->rows;
359 kp->n_cols = pdata->cols;
360 kp->irq = platform_get_irq(pdev, 0);
361
362 /* setup input device */
363 __set_bit(EV_KEY, input->evbit);
364
365 /* Enable auto repeat feature of Linux input subsystem */
366 if (pdata->rep)
367 __set_bit(EV_REP, input->evbit);
368
369 input_set_capability(input, EV_MSC, MSC_SCAN);
370
371 input->name = "TWL4030 Keypad";
372 input->phys = "twl4030_keypad/input0";
373 input->dev.parent = &pdev->dev;
374
375 input->id.bustype = BUS_HOST;
376 input->id.vendor = 0x0001;
377 input->id.product = 0x0001;
378 input->id.version = 0x0003;
379
380 input->keycode = kp->keymap;
381 input->keycodesize = sizeof(kp->keymap[0]);
382 input->keycodemax = ARRAY_SIZE(kp->keymap);
383
384 matrix_keypad_build_keymap(keymap_data, TWL4030_ROW_SHIFT,
385 input->keycode, input->keybit);
386
387 error = input_register_device(input);
388 if (error) {
389 dev_err(kp->dbg_dev,
390 "Unable to register twl4030 keypad device\n");
391 goto err1;
392 }
393
394 error = twl4030_kp_program(kp);
395 if (error)
396 goto err2;
397
398 /*
399 * This ISR will always execute in kernel thread context because of
400 * the need to access the TWL4030 over the I2C bus.
401 *
402 * NOTE: we assume this host is wired to TWL4040 INT1, not INT2 ...
403 */
Felipe Balbi3f580612009-12-29 23:15:51 -0800404 error = request_threaded_irq(kp->irq, NULL, do_kp_irq,
405 0, pdev->name, kp);
David Brownell9d834062009-08-25 19:24:14 -0700406 if (error) {
407 dev_info(kp->dbg_dev, "request_irq failed for irq no=%d\n",
408 kp->irq);
409 goto err3;
410 }
411
412 /* Enable KP and TO interrupts now. */
413 reg = (u8) ~(KEYP_IMR1_KP | KEYP_IMR1_TO);
414 if (twl4030_kpwrite_u8(kp, reg, KEYP_IMR1)) {
415 error = -EIO;
416 goto err4;
417 }
418
419 platform_set_drvdata(pdev, kp);
420 return 0;
421
422err4:
423 /* mask all events - we don't care about the result */
424 (void) twl4030_kpwrite_u8(kp, 0xff, KEYP_IMR1);
425err3:
426 free_irq(kp->irq, NULL);
427err2:
428 input_unregister_device(input);
429 input = NULL;
430err1:
431 input_free_device(input);
432 kfree(kp);
433 return error;
434}
435
436static int __devexit twl4030_kp_remove(struct platform_device *pdev)
437{
438 struct twl4030_keypad *kp = platform_get_drvdata(pdev);
439
440 free_irq(kp->irq, kp);
441 input_unregister_device(kp->input);
442 platform_set_drvdata(pdev, NULL);
443 kfree(kp);
444
445 return 0;
446}
447
448/*
449 * NOTE: twl4030 are multi-function devices connected via I2C.
450 * So this device is a child of an I2C parent, thus it needs to
451 * support unplug/replug (which most platform devices don't).
452 */
453
454static struct platform_driver twl4030_kp_driver = {
455 .probe = twl4030_kp_probe,
456 .remove = __devexit_p(twl4030_kp_remove),
457 .driver = {
458 .name = "twl4030_keypad",
459 .owner = THIS_MODULE,
460 },
461};
462
463static int __init twl4030_kp_init(void)
464{
465 return platform_driver_register(&twl4030_kp_driver);
466}
467module_init(twl4030_kp_init);
468
469static void __exit twl4030_kp_exit(void)
470{
471 platform_driver_unregister(&twl4030_kp_driver);
472}
473module_exit(twl4030_kp_exit);
474
475MODULE_AUTHOR("Texas Instruments");
476MODULE_DESCRIPTION("TWL4030 Keypad Driver");
477MODULE_LICENSE("GPL");
478MODULE_ALIAS("platform:twl4030_keypad");
479