1 /* 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/interrupt.h> 31 #include <linux/input.h> 32 #include <linux/platform_device.h> 33 #include <linux/i2c/twl.h> 34 #include <linux/slab.h> 35 #include <linux/of.h> 36 37 /* 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. 43 * 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. 47 * 48 * See the TPS65950 documentation; that's the general availability 49 * version of the TWL5030 second generation part. 50 */ 51 #define TWL4030_MAX_ROWS 8 /* TWL4030 hard limit */ 52 #define TWL4030_MAX_COLS 8 53 /* 54 * Note that we add space for an extra column so that we can handle 55 * row lines connected to the gnd (see twl4030_col_xlate()). 56 */ 57 #define TWL4030_ROW_SHIFT 4 58 #define TWL4030_KEYMAP_SIZE (TWL4030_MAX_ROWS << TWL4030_ROW_SHIFT) 59 60 struct twl4030_keypad { 61 unsigned short keymap[TWL4030_KEYMAP_SIZE]; 62 u16 kp_state[TWL4030_MAX_ROWS]; 63 bool autorepeat; 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 /*----------------------------------------------------------------------*/ 137 138 static int twl4030_kpread(struct twl4030_keypad *kp, 139 u8 *data, u32 reg, u8 num_bytes) 140 { 141 int ret = twl_i2c_read(TWL4030_MODULE_KEYPAD, data, reg, num_bytes); 142 143 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 } 150 151 static int twl4030_kpwrite_u8(struct twl4030_keypad *kp, u8 data, u32 reg) 152 { 153 int ret = twl_i2c_write_u8(TWL4030_MODULE_KEYPAD, data, reg); 154 155 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 } 162 163 static 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 } 175 176 static 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 } 188 189 static bool twl4030_is_in_ghost_state(struct twl4030_keypad *kp, u16 *key_state) 190 { 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) 198 return true; 199 200 check |= col; 201 } 202 203 return false; 204 } 205 206 static 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; 231 232 /* Extra column handles "all gnd" rows */ 233 for (col = 0; col < kp->n_cols + 1; col++) { 234 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 */ 256 static irqreturn_t do_kp_irq(int irq, void *_kp) 257 { 258 struct twl4030_keypad *kp = _kp; 259 u8 reg; 260 int ret; 261 262 /* Read & Clear TWL4030 pending interrupt */ 263 ret = twl4030_kpread(kp, ®, 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 } 274 275 static int 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 200 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 */ 332 static int twl4030_kp_probe(struct platform_device *pdev) 333 { 334 struct twl4030_keypad_data *pdata = dev_get_platdata(&pdev->dev); 335 const struct matrix_keymap_data *keymap_data = NULL; 336 struct twl4030_keypad *kp; 337 struct input_dev *input; 338 u8 reg; 339 int error; 340 341 kp = devm_kzalloc(&pdev->dev, sizeof(*kp), GFP_KERNEL); 342 if (!kp) 343 return -ENOMEM; 344 345 input = devm_input_allocate_device(&pdev->dev); 346 if (!input) 347 return -ENOMEM; 348 349 /* get the debug device */ 350 kp->dbg_dev = &pdev->dev; 351 kp->input = input; 352 353 /* setup input device */ 354 input->name = "TWL4030 Keypad"; 355 input->phys = "twl4030_keypad/input0"; 356 357 input->id.bustype = BUS_HOST; 358 input->id.vendor = 0x0001; 359 input->id.product = 0x0001; 360 input->id.version = 0x0003; 361 362 if (pdata) { 363 if (!pdata->rows || !pdata->cols || !pdata->keymap_data) { 364 dev_err(&pdev->dev, "Missing platform_data\n"); 365 return -EINVAL; 366 } 367 368 kp->n_rows = pdata->rows; 369 kp->n_cols = pdata->cols; 370 kp->autorepeat = pdata->rep; 371 keymap_data = pdata->keymap_data; 372 } else { 373 error = matrix_keypad_parse_of_params(&pdev->dev, &kp->n_rows, 374 &kp->n_cols); 375 if (error) 376 return error; 377 378 kp->autorepeat = true; 379 } 380 381 if (kp->n_rows > TWL4030_MAX_ROWS || kp->n_cols > TWL4030_MAX_COLS) { 382 dev_err(&pdev->dev, 383 "Invalid rows/cols amount specified in platform/devicetree data\n"); 384 return -EINVAL; 385 } 386 387 kp->irq = platform_get_irq(pdev, 0); 388 if (!kp->irq) { 389 dev_err(&pdev->dev, "no keyboard irq assigned\n"); 390 return -EINVAL; 391 } 392 393 error = matrix_keypad_build_keymap(keymap_data, NULL, 394 TWL4030_MAX_ROWS, 395 1 << TWL4030_ROW_SHIFT, 396 kp->keymap, input); 397 if (error) { 398 dev_err(kp->dbg_dev, "Failed to build keymap\n"); 399 return error; 400 } 401 402 input_set_capability(input, EV_MSC, MSC_SCAN); 403 /* Enable auto repeat feature of Linux input subsystem */ 404 if (kp->autorepeat) 405 __set_bit(EV_REP, input->evbit); 406 407 error = input_register_device(input); 408 if (error) { 409 dev_err(kp->dbg_dev, 410 "Unable to register twl4030 keypad device\n"); 411 return error; 412 } 413 414 error = twl4030_kp_program(kp); 415 if (error) 416 return error; 417 418 /* 419 * This ISR will always execute in kernel thread context because of 420 * the need to access the TWL4030 over the I2C bus. 421 * 422 * NOTE: we assume this host is wired to TWL4040 INT1, not INT2 ... 423 */ 424 error = devm_request_threaded_irq(&pdev->dev, kp->irq, NULL, do_kp_irq, 425 0, pdev->name, kp); 426 if (error) { 427 dev_info(kp->dbg_dev, "request_irq failed for irq no=%d: %d\n", 428 kp->irq, error); 429 return error; 430 } 431 432 /* Enable KP and TO interrupts now. */ 433 reg = (u8) ~(KEYP_IMR1_KP | KEYP_IMR1_TO); 434 if (twl4030_kpwrite_u8(kp, reg, KEYP_IMR1)) { 435 /* mask all events - we don't care about the result */ 436 (void) twl4030_kpwrite_u8(kp, 0xff, KEYP_IMR1); 437 return -EIO; 438 } 439 440 platform_set_drvdata(pdev, kp); 441 return 0; 442 } 443 444 #ifdef CONFIG_OF 445 static const struct of_device_id twl4030_keypad_dt_match_table[] = { 446 { .compatible = "ti,twl4030-keypad" }, 447 {}, 448 }; 449 MODULE_DEVICE_TABLE(of, twl4030_keypad_dt_match_table); 450 #endif 451 452 /* 453 * NOTE: twl4030 are multi-function devices connected via I2C. 454 * So this device is a child of an I2C parent, thus it needs to 455 * support unplug/replug (which most platform devices don't). 456 */ 457 458 static struct platform_driver twl4030_kp_driver = { 459 .probe = twl4030_kp_probe, 460 .driver = { 461 .name = "twl4030_keypad", 462 .of_match_table = of_match_ptr(twl4030_keypad_dt_match_table), 463 }, 464 }; 465 module_platform_driver(twl4030_kp_driver); 466 467 MODULE_AUTHOR("Texas Instruments"); 468 MODULE_DESCRIPTION("TWL4030 Keypad Driver"); 469 MODULE_LICENSE("GPL"); 470 MODULE_ALIAS("platform:twl4030_keypad"); 471