2 * twl4030_keypad.c - driver for 8x8 keypad controller in twl4030 chips
4 * Copyright (C) 2007 Texas Instruments, Inc.
5 * Copyright (C) 2008 Nokia Corporation
7 * Code re-written for 2430SDP by:
8 * Syed Mohammed Khasim <x0khasim@ti.com>
11 * Manjunatha G K <manjugk@ti.com>
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.
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.
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
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>
34 #include <linux/i2c/twl.h>
38 * The TWL4030 family chips include a keypad controller that supports
39 * up to an 8x8 switch matrix. The controller can issue system wakeup
40 * events, since it uses only the always-on 32KiHz oscillator, and has
41 * an internal state machine that decodes pressed keys, including
42 * multi-key combinations.
44 * This driver lets boards define what keycodes they wish to report for
45 * which scancodes, as part of the "struct twl4030_keypad_data" used in
46 * the probe() routine.
48 * See the TPS65950 documentation; that's the general availability
49 * version of the TWL5030 second generation part.
51 #define TWL4030_MAX_ROWS 8 /* TWL4030 hard limit */
52 #define TWL4030_MAX_COLS 8
53 #define TWL4030_ROW_SHIFT 3
54 #define TWL4030_KEYMAP_SIZE (TWL4030_MAX_ROWS * TWL4030_MAX_COLS)
56 struct twl4030_keypad {
57 unsigned short keymap[TWL4030_KEYMAP_SIZE];
58 u16 kp_state[TWL4030_MAX_ROWS];
63 struct device *dbg_dev;
64 struct input_dev *input;
67 /*----------------------------------------------------------------------*/
69 /* arbitrary prescaler value 0..7 */
70 #define PTV_PRESCALER 4
72 /* Register Offsets */
73 #define KEYP_CTRL 0x00
75 #define KEYP_LONG_KEY 0x02
76 #define KEYP_LK_PTV 0x03
77 #define KEYP_TIMEOUT_L 0x04
78 #define KEYP_TIMEOUT_H 0x05
82 #define KEYP_FULL_CODE_7_0 0x09 /* row 0 column status */
83 #define KEYP_FULL_CODE_15_8 0x0a /* ... row 1 ... */
84 #define KEYP_FULL_CODE_23_16 0x0b
85 #define KEYP_FULL_CODE_31_24 0x0c
86 #define KEYP_FULL_CODE_39_32 0x0d
87 #define KEYP_FULL_CODE_47_40 0x0e
88 #define KEYP_FULL_CODE_55_48 0x0f
89 #define KEYP_FULL_CODE_63_56 0x10
90 #define KEYP_ISR1 0x11
91 #define KEYP_IMR1 0x12
92 #define KEYP_ISR2 0x13
93 #define KEYP_IMR2 0x14
95 #define KEYP_EDR 0x16 /* edge triggers */
96 #define KEYP_SIH_CTRL 0x17
98 /* KEYP_CTRL_REG Fields */
99 #define KEYP_CTRL_SOFT_NRST BIT(0)
100 #define KEYP_CTRL_SOFTMODEN BIT(1)
101 #define KEYP_CTRL_LK_EN BIT(2)
102 #define KEYP_CTRL_TOE_EN BIT(3)
103 #define KEYP_CTRL_TOLE_EN BIT(4)
104 #define KEYP_CTRL_RP_EN BIT(5)
105 #define KEYP_CTRL_KBD_ON BIT(6)
107 /* KEYP_DEB, KEYP_LONG_KEY, KEYP_TIMEOUT_x*/
108 #define KEYP_PERIOD_US(t, prescale) ((t) / (31 << (prescale + 1)) - 1)
110 /* KEYP_LK_PTV_REG Fields */
111 #define KEYP_LK_PTV_PTV_SHIFT 5
113 /* KEYP_{IMR,ISR,SIR} Fields */
114 #define KEYP_IMR1_MIS BIT(3)
115 #define KEYP_IMR1_TO BIT(2)
116 #define KEYP_IMR1_LK BIT(1)
117 #define KEYP_IMR1_KP BIT(0)
119 /* KEYP_EDR Fields */
120 #define KEYP_EDR_KP_FALLING 0x01
121 #define KEYP_EDR_KP_RISING 0x02
122 #define KEYP_EDR_KP_BOTH 0x03
123 #define KEYP_EDR_LK_FALLING 0x04
124 #define KEYP_EDR_LK_RISING 0x08
125 #define KEYP_EDR_TO_FALLING 0x10
126 #define KEYP_EDR_TO_RISING 0x20
127 #define KEYP_EDR_MIS_FALLING 0x40
128 #define KEYP_EDR_MIS_RISING 0x80
131 /*----------------------------------------------------------------------*/
133 static int twl4030_kpread(struct twl4030_keypad *kp,
134 u8 *data, u32 reg, u8 num_bytes)
136 int ret = twl_i2c_read(TWL4030_MODULE_KEYPAD, data, reg, num_bytes);
139 dev_warn(kp->dbg_dev,
140 "Couldn't read TWL4030: %X - ret %d[%x]\n",
146 static int twl4030_kpwrite_u8(struct twl4030_keypad *kp, u8 data, u32 reg)
148 int ret = twl_i2c_write_u8(TWL4030_MODULE_KEYPAD, data, reg);
151 dev_warn(kp->dbg_dev,
152 "Could not write TWL4030: %X - ret %d[%x]\n",
158 static inline u16 twl4030_col_xlate(struct twl4030_keypad *kp, u8 col)
160 /* If all bits in a row are active for all coloumns then
161 * we have that row line connected to gnd. Mark this
162 * key on as if it was on matrix position n_cols (ie
163 * one higher than the size of the matrix).
166 return 1 << kp->n_cols;
168 return col & ((1 << kp->n_cols) - 1);
171 static int twl4030_read_kp_matrix_state(struct twl4030_keypad *kp, u16 *state)
173 u8 new_state[TWL4030_MAX_ROWS];
175 int ret = twl4030_kpread(kp, new_state,
176 KEYP_FULL_CODE_7_0, kp->n_rows);
178 for (row = 0; row < kp->n_rows; row++)
179 state[row] = twl4030_col_xlate(kp, new_state[row]);
184 static int twl4030_is_in_ghost_state(struct twl4030_keypad *kp, u16 *key_state)
189 for (i = 0; i < kp->n_rows; i++) {
190 u16 col = key_state[i];
192 if ((col & check) && hweight16(col) > 1)
201 static void twl4030_kp_scan(struct twl4030_keypad *kp, bool release_all)
203 struct input_dev *input = kp->input;
204 u16 new_state[TWL4030_MAX_ROWS];
208 memset(new_state, 0, sizeof(new_state));
210 /* check for any changes */
211 int ret = twl4030_read_kp_matrix_state(kp, new_state);
213 if (ret < 0) /* panic ... */
216 if (twl4030_is_in_ghost_state(kp, new_state))
220 /* check for changes and print those */
221 for (row = 0; row < kp->n_rows; row++) {
222 int changed = new_state[row] ^ kp->kp_state[row];
227 for (col = 0; col < kp->n_cols; col++) {
230 if (!(changed & (1 << col)))
233 dev_dbg(kp->dbg_dev, "key [%d:%d] %s\n", row, col,
234 (new_state[row] & (1 << col)) ?
235 "press" : "release");
237 code = MATRIX_SCAN_CODE(row, col, TWL4030_ROW_SHIFT);
238 input_event(input, EV_MSC, MSC_SCAN, code);
239 input_report_key(input, kp->keymap[code],
240 new_state[row] & (1 << col));
242 kp->kp_state[row] = new_state[row];
248 * Keypad interrupt handler
250 static irqreturn_t do_kp_irq(int irq, void *_kp)
252 struct twl4030_keypad *kp = _kp;
256 /* Read & Clear TWL4030 pending interrupt */
257 ret = twl4030_kpread(kp, ®, KEYP_ISR1, 1);
259 /* Release all keys if I2C has gone bad or
260 * the KEYP has gone to idle state */
261 if (ret >= 0 && (reg & KEYP_IMR1_KP))
262 twl4030_kp_scan(kp, false);
264 twl4030_kp_scan(kp, true);
269 static int __devinit twl4030_kp_program(struct twl4030_keypad *kp)
274 /* Enable controller, with hardware decoding but not autorepeat */
275 reg = KEYP_CTRL_SOFT_NRST | KEYP_CTRL_SOFTMODEN
276 | KEYP_CTRL_TOE_EN | KEYP_CTRL_KBD_ON;
277 if (twl4030_kpwrite_u8(kp, reg, KEYP_CTRL) < 0)
280 /* NOTE: we could use sih_setup() here to package keypad
281 * event sources as four different IRQs ... but we don't.
284 /* Enable TO rising and KP rising and falling edge detection */
285 reg = KEYP_EDR_KP_BOTH | KEYP_EDR_TO_RISING;
286 if (twl4030_kpwrite_u8(kp, reg, KEYP_EDR) < 0)
289 /* Set PTV prescaler Field */
290 reg = (PTV_PRESCALER << KEYP_LK_PTV_PTV_SHIFT);
291 if (twl4030_kpwrite_u8(kp, reg, KEYP_LK_PTV) < 0)
294 /* Set key debounce time to 20 ms */
295 i = KEYP_PERIOD_US(20000, PTV_PRESCALER);
296 if (twl4030_kpwrite_u8(kp, i, KEYP_DEB) < 0)
299 /* Set timeout period to 100 ms */
300 i = KEYP_PERIOD_US(200000, PTV_PRESCALER);
301 if (twl4030_kpwrite_u8(kp, (i & 0xFF), KEYP_TIMEOUT_L) < 0)
304 if (twl4030_kpwrite_u8(kp, (i >> 8), KEYP_TIMEOUT_H) < 0)
308 * Enable Clear-on-Read; disable remembering events that fire
309 * after the IRQ but before our handler acks (reads) them,
311 reg = TWL4030_SIH_CTRL_COR_MASK | TWL4030_SIH_CTRL_PENDDIS_MASK;
312 if (twl4030_kpwrite_u8(kp, reg, KEYP_SIH_CTRL) < 0)
315 /* initialize key state; irqs update it from here on */
316 if (twl4030_read_kp_matrix_state(kp, kp->kp_state) < 0)
323 * Registers keypad device with input subsystem
324 * and configures TWL4030 keypad registers
326 static int __devinit twl4030_kp_probe(struct platform_device *pdev)
328 struct twl4030_keypad_data *pdata = pdev->dev.platform_data;
329 const struct matrix_keymap_data *keymap_data = pdata->keymap_data;
330 struct twl4030_keypad *kp;
331 struct input_dev *input;
335 if (!pdata || !pdata->rows || !pdata->cols ||
336 pdata->rows > TWL4030_MAX_ROWS || pdata->cols > TWL4030_MAX_COLS) {
337 dev_err(&pdev->dev, "Invalid platform_data\n");
341 kp = kzalloc(sizeof(*kp), GFP_KERNEL);
342 input = input_allocate_device();
348 /* Get the debug Device */
349 kp->dbg_dev = &pdev->dev;
352 kp->n_rows = pdata->rows;
353 kp->n_cols = pdata->cols;
354 kp->irq = platform_get_irq(pdev, 0);
356 /* setup input device */
357 __set_bit(EV_KEY, input->evbit);
359 /* Enable auto repeat feature of Linux input subsystem */
361 __set_bit(EV_REP, input->evbit);
363 input_set_capability(input, EV_MSC, MSC_SCAN);
365 input->name = "TWL4030 Keypad";
366 input->phys = "twl4030_keypad/input0";
367 input->dev.parent = &pdev->dev;
369 input->id.bustype = BUS_HOST;
370 input->id.vendor = 0x0001;
371 input->id.product = 0x0001;
372 input->id.version = 0x0003;
374 input->keycode = kp->keymap;
375 input->keycodesize = sizeof(kp->keymap[0]);
376 input->keycodemax = ARRAY_SIZE(kp->keymap);
378 matrix_keypad_build_keymap(keymap_data, TWL4030_ROW_SHIFT,
379 input->keycode, input->keybit);
381 error = input_register_device(input);
384 "Unable to register twl4030 keypad device\n");
388 error = twl4030_kp_program(kp);
393 * This ISR will always execute in kernel thread context because of
394 * the need to access the TWL4030 over the I2C bus.
396 * NOTE: we assume this host is wired to TWL4040 INT1, not INT2 ...
398 error = request_threaded_irq(kp->irq, NULL, do_kp_irq,
401 dev_info(kp->dbg_dev, "request_irq failed for irq no=%d\n",
406 /* Enable KP and TO interrupts now. */
407 reg = (u8) ~(KEYP_IMR1_KP | KEYP_IMR1_TO);
408 if (twl4030_kpwrite_u8(kp, reg, KEYP_IMR1)) {
413 platform_set_drvdata(pdev, kp);
417 /* mask all events - we don't care about the result */
418 (void) twl4030_kpwrite_u8(kp, 0xff, KEYP_IMR1);
420 free_irq(kp->irq, NULL);
422 input_unregister_device(input);
425 input_free_device(input);
430 static int __devexit twl4030_kp_remove(struct platform_device *pdev)
432 struct twl4030_keypad *kp = platform_get_drvdata(pdev);
434 free_irq(kp->irq, kp);
435 input_unregister_device(kp->input);
436 platform_set_drvdata(pdev, NULL);
443 * NOTE: twl4030 are multi-function devices connected via I2C.
444 * So this device is a child of an I2C parent, thus it needs to
445 * support unplug/replug (which most platform devices don't).
448 static struct platform_driver twl4030_kp_driver = {
449 .probe = twl4030_kp_probe,
450 .remove = __devexit_p(twl4030_kp_remove),
452 .name = "twl4030_keypad",
453 .owner = THIS_MODULE,
457 static int __init twl4030_kp_init(void)
459 return platform_driver_register(&twl4030_kp_driver);
461 module_init(twl4030_kp_init);
463 static void __exit twl4030_kp_exit(void)
465 platform_driver_unregister(&twl4030_kp_driver);
467 module_exit(twl4030_kp_exit);
469 MODULE_AUTHOR("Texas Instruments");
470 MODULE_DESCRIPTION("TWL4030 Keypad Driver");
471 MODULE_LICENSE("GPL");
472 MODULE_ALIAS("platform:twl4030_keypad");