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/twl4030.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 MAX_ROWS 8 /* TWL4030 hard limit */
53 struct twl4030_keypad {
55 unsigned int keymapsize;
56 u16 kp_state[MAX_ROWS];
61 struct device *dbg_dev;
62 struct input_dev *input;
65 #define ROWCOL_MASK KEY(0xf, 0xf, 0)
66 #define KEYNUM_MASK ~PERSISTENT_KEY(0xf, 0xf)
68 /*----------------------------------------------------------------------*/
70 /* arbitrary prescaler value 0..7 */
71 #define PTV_PRESCALER 4
73 /* Register Offsets */
74 #define KEYP_CTRL 0x00
76 #define KEYP_LONG_KEY 0x02
77 #define KEYP_LK_PTV 0x03
78 #define KEYP_TIMEOUT_L 0x04
79 #define KEYP_TIMEOUT_H 0x05
83 #define KEYP_FULL_CODE_7_0 0x09 /* row 0 column status */
84 #define KEYP_FULL_CODE_15_8 0x0a /* ... row 1 ... */
85 #define KEYP_FULL_CODE_23_16 0x0b
86 #define KEYP_FULL_CODE_31_24 0x0c
87 #define KEYP_FULL_CODE_39_32 0x0d
88 #define KEYP_FULL_CODE_47_40 0x0e
89 #define KEYP_FULL_CODE_55_48 0x0f
90 #define KEYP_FULL_CODE_63_56 0x10
91 #define KEYP_ISR1 0x11
92 #define KEYP_IMR1 0x12
93 #define KEYP_ISR2 0x13
94 #define KEYP_IMR2 0x14
96 #define KEYP_EDR 0x16 /* edge triggers */
97 #define KEYP_SIH_CTRL 0x17
99 /* KEYP_CTRL_REG Fields */
100 #define KEYP_CTRL_SOFT_NRST BIT(0)
101 #define KEYP_CTRL_SOFTMODEN BIT(1)
102 #define KEYP_CTRL_LK_EN BIT(2)
103 #define KEYP_CTRL_TOE_EN BIT(3)
104 #define KEYP_CTRL_TOLE_EN BIT(4)
105 #define KEYP_CTRL_RP_EN BIT(5)
106 #define KEYP_CTRL_KBD_ON BIT(6)
108 /* KEYP_DEB, KEYP_LONG_KEY, KEYP_TIMEOUT_x*/
109 #define KEYP_PERIOD_US(t, prescale) ((t) / (31 << (prescale + 1)) - 1)
111 /* KEYP_LK_PTV_REG Fields */
112 #define KEYP_LK_PTV_PTV_SHIFT 5
114 /* KEYP_{IMR,ISR,SIR} Fields */
115 #define KEYP_IMR1_MIS BIT(3)
116 #define KEYP_IMR1_TO BIT(2)
117 #define KEYP_IMR1_LK BIT(1)
118 #define KEYP_IMR1_KP BIT(0)
120 /* KEYP_EDR Fields */
121 #define KEYP_EDR_KP_FALLING 0x01
122 #define KEYP_EDR_KP_RISING 0x02
123 #define KEYP_EDR_KP_BOTH 0x03
124 #define KEYP_EDR_LK_FALLING 0x04
125 #define KEYP_EDR_LK_RISING 0x08
126 #define KEYP_EDR_TO_FALLING 0x10
127 #define KEYP_EDR_TO_RISING 0x20
128 #define KEYP_EDR_MIS_FALLING 0x40
129 #define KEYP_EDR_MIS_RISING 0x80
132 /*----------------------------------------------------------------------*/
134 static int twl4030_kpread(struct twl4030_keypad *kp,
135 u8 *data, u32 reg, u8 num_bytes)
139 ret = twl4030_i2c_read(TWL4030_MODULE_KEYPAD, data, reg, num_bytes);
141 dev_warn(kp->dbg_dev,
142 "Couldn't read TWL4030: %X - ret %d[%x]\n",
149 static int twl4030_kpwrite_u8(struct twl4030_keypad *kp, u8 data, u32 reg)
153 ret = twl4030_i2c_write_u8(TWL4030_MODULE_KEYPAD, data, reg);
155 dev_warn(kp->dbg_dev,
156 "Could not write TWL4030: %X - ret %d[%x]\n",
163 static int twl4030_find_key(struct twl4030_keypad *kp, int col, int row)
167 rc = KEY(col, row, 0);
168 for (i = 0; i < kp->keymapsize; i++)
169 if ((kp->keymap[i] & ROWCOL_MASK) == rc)
170 return kp->keymap[i] & (KEYNUM_MASK | KEY_PERSISTENT);
175 static inline u16 twl4030_col_xlate(struct twl4030_keypad *kp, u8 col)
177 /* If all bits in a row are active for all coloumns then
178 * we have that row line connected to gnd. Mark this
179 * key on as if it was on matrix position n_cols (ie
180 * one higher than the size of the matrix).
183 return 1 << kp->n_cols;
185 return col & ((1 << kp->n_cols) - 1);
188 static int twl4030_read_kp_matrix_state(struct twl4030_keypad *kp, u16 *state)
190 u8 new_state[MAX_ROWS];
192 int ret = twl4030_kpread(kp,
193 new_state, KEYP_FULL_CODE_7_0, kp->n_rows);
195 for (row = 0; row < kp->n_rows; row++)
196 state[row] = twl4030_col_xlate(kp, new_state[row]);
201 static int twl4030_is_in_ghost_state(struct twl4030_keypad *kp, u16 *key_state)
206 for (i = 0; i < kp->n_rows; i++) {
207 u16 col = key_state[i];
209 if ((col & check) && hweight16(col) > 1)
217 static void twl4030_kp_scan(struct twl4030_keypad *kp, int release_all)
219 u16 new_state[MAX_ROWS];
223 memset(new_state, 0, sizeof(new_state));
225 /* check for any changes */
226 int ret = twl4030_read_kp_matrix_state(kp, new_state);
228 if (ret < 0) /* panic ... */
230 if (twl4030_is_in_ghost_state(kp, new_state))
234 /* check for changes and print those */
235 for (row = 0; row < kp->n_rows; row++) {
236 int changed = new_state[row] ^ kp->kp_state[row];
241 for (col = 0; col < kp->n_cols; col++) {
244 if (!(changed & (1 << col)))
247 dev_dbg(kp->dbg_dev, "key [%d:%d] %s\n", row, col,
248 (new_state[row] & (1 << col)) ?
249 "press" : "release");
251 key = twl4030_find_key(kp, col, row);
253 dev_warn(kp->dbg_dev,
254 "Spurious key event %d-%d\n",
256 else if (key & KEY_PERSISTENT)
259 input_report_key(kp->input, key,
260 new_state[row] & (1 << col));
262 kp->kp_state[row] = new_state[row];
264 input_sync(kp->input);
268 * Keypad interrupt handler
270 static irqreturn_t do_kp_irq(int irq, void *_kp)
272 struct twl4030_keypad *kp = _kp;
276 #ifdef CONFIG_LOCKDEP
277 /* WORKAROUND for lockdep forcing IRQF_DISABLED on us, which
278 * we don't want and can't tolerate. Although it might be
279 * friendlier not to borrow this thread context...
284 /* Read & Clear TWL4030 pending interrupt */
285 ret = twl4030_kpread(kp, ®, KEYP_ISR1, 1);
287 /* Release all keys if I2C has gone bad or
288 * the KEYP has gone to idle state */
289 if ((ret >= 0) && (reg & KEYP_IMR1_KP))
290 twl4030_kp_scan(kp, 0);
292 twl4030_kp_scan(kp, 1);
298 * Registers keypad device with input subsystem
299 * and configures TWL4030 keypad registers
301 static int __devinit twl4030_kp_probe(struct platform_device *pdev)
306 struct twl4030_keypad *kp;
307 struct twl4030_keypad_data *pdata = pdev->dev.platform_data;
309 if (!pdata || !pdata->rows || !pdata->cols || !pdata->keymap
310 || pdata->rows > 8 || pdata->cols > 8) {
311 dev_err(&pdev->dev, "Invalid platform_data\n");
315 kp = kzalloc(sizeof(*kp), GFP_KERNEL);
319 platform_set_drvdata(pdev, kp);
321 /* Get the debug Device */
322 kp->dbg_dev = &pdev->dev;
324 kp->input = input_allocate_device();
330 kp->keymap = pdata->keymap;
331 kp->keymapsize = pdata->keymapsize;
332 kp->n_rows = pdata->rows;
333 kp->n_cols = pdata->cols;
334 kp->irq = platform_get_irq(pdev, 0);
336 /* setup input device */
337 __set_bit(EV_KEY, kp->input->evbit);
339 /* Enable auto repeat feature of Linux input subsystem */
341 __set_bit(EV_REP, kp->input->evbit);
343 for (i = 0; i < kp->keymapsize; i++)
344 __set_bit(kp->keymap[i] & KEYNUM_MASK,
347 kp->input->name = "TWL4030 Keypad";
348 kp->input->phys = "twl4030_keypad/input0";
349 kp->input->dev.parent = &pdev->dev;
351 kp->input->id.bustype = BUS_HOST;
352 kp->input->id.vendor = 0x0001;
353 kp->input->id.product = 0x0001;
354 kp->input->id.version = 0x0003;
356 kp->input->keycode = kp->keymap;
357 kp->input->keycodesize = sizeof(unsigned int);
358 kp->input->keycodemax = kp->keymapsize;
360 ret = input_register_device(kp->input);
363 "Unable to register twl4030 keypad device\n");
367 /* Enable controller, with hardware decoding but not autorepeat */
368 reg = KEYP_CTRL_SOFT_NRST | KEYP_CTRL_SOFTMODEN
369 | KEYP_CTRL_TOE_EN | KEYP_CTRL_KBD_ON;
370 ret = twl4030_kpwrite_u8(kp, reg, KEYP_CTRL);
374 /* NOTE: we could use sih_setup() here to package keypad
375 * event sources as four different IRQs ... but we don't.
378 /* Enable TO rising and KP rising and falling edge detection */
379 reg = KEYP_EDR_KP_BOTH | KEYP_EDR_TO_RISING;
380 ret = twl4030_kpwrite_u8(kp, reg, KEYP_EDR);
384 /* Set PTV prescaler Field */
385 reg = (PTV_PRESCALER << KEYP_LK_PTV_PTV_SHIFT);
386 ret = twl4030_kpwrite_u8(kp, reg, KEYP_LK_PTV);
390 /* Set key debounce time to 20 ms */
391 i = KEYP_PERIOD_US(20000, PTV_PRESCALER);
392 ret = twl4030_kpwrite_u8(kp, i, KEYP_DEB);
396 /* Set timeout period to 100 ms */
397 i = KEYP_PERIOD_US(200000, PTV_PRESCALER);
398 ret = twl4030_kpwrite_u8(kp, (i & 0xFF), KEYP_TIMEOUT_L);
401 ret = twl4030_kpwrite_u8(kp, (i >> 8), KEYP_TIMEOUT_H);
405 /* Enable Clear-on-Read; disable remembering events that fire
406 * after the IRQ but before our handler acks (reads) them,
408 reg = TWL4030_SIH_CTRL_COR_MASK | TWL4030_SIH_CTRL_PENDDIS_MASK;
409 ret = twl4030_kpwrite_u8(kp, reg, KEYP_SIH_CTRL);
413 /* initialize key state; irqs update it from here on */
414 ret = twl4030_read_kp_matrix_state(kp, kp->kp_state);
419 * This ISR will always execute in kernel thread context because of
420 * the need to access the TWL4030 over the I2C bus.
422 * NOTE: we assume this host is wired to TWL4040 INT1, not INT2 ...
424 ret = request_irq(kp->irq, do_kp_irq, 0, pdev->name, kp);
426 dev_info(kp->dbg_dev, "request_irq failed for irq no=%d\n",
430 /* Enable KP and TO interrupts now. */
431 reg = (u8) ~(KEYP_IMR1_KP | KEYP_IMR1_TO);
432 ret = twl4030_kpwrite_u8(kp, reg, KEYP_IMR1);
439 /* mask all events - we don't care about the result */
440 (void) twl4030_kpwrite_u8(kp, 0xff, KEYP_IMR1);
441 free_irq(kp->irq, NULL);
443 input_unregister_device(kp->input);
446 input_free_device(kp->input);
451 static int __devexit twl4030_kp_remove(struct platform_device *pdev)
453 struct twl4030_keypad *kp = platform_get_drvdata(pdev);
455 free_irq(kp->irq, kp);
456 input_unregister_device(kp->input);
463 * NOTE: twl4030 are multi-function devices connected via I2C.
464 * So this device is a child of an I2C parent, thus it needs to
465 * support unplug/replug (which most platform devices don't).
468 MODULE_ALIAS("platform:twl4030_keypad");
470 static struct platform_driver twl4030_kp_driver = {
471 .probe = twl4030_kp_probe,
472 .remove = __devexit_p(twl4030_kp_remove),
474 .name = "twl4030_keypad",
475 .owner = THIS_MODULE,
479 static int __init twl4030_kp_init(void)
481 return platform_driver_register(&twl4030_kp_driver);
483 module_init(twl4030_kp_init);
485 static void __exit twl4030_kp_exit(void)
487 platform_driver_unregister(&twl4030_kp_driver);
489 module_exit(twl4030_kp_exit);
491 MODULE_AUTHOR("Texas Instruments");
492 MODULE_DESCRIPTION("TWL4030 Keypad Driver");
493 MODULE_LICENSE("GPL");