1 /* 2 * Copyright (C) 2012 Samsung Electronics Co.Ltd 3 * Author: Joonyoung Shim <jy0922.shim@samsung.com> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 */ 9 10 #include <linux/module.h> 11 #include <linux/init.h> 12 #include <linux/delay.h> 13 #include <linux/of.h> 14 #include <linux/i2c.h> 15 #include <linux/i2c/mms114.h> 16 #include <linux/input/mt.h> 17 #include <linux/interrupt.h> 18 #include <linux/regulator/consumer.h> 19 #include <linux/slab.h> 20 21 /* Write only registers */ 22 #define MMS114_MODE_CONTROL 0x01 23 #define MMS114_OPERATION_MODE_MASK 0xE 24 #define MMS114_ACTIVE (1 << 1) 25 26 #define MMS114_XY_RESOLUTION_H 0x02 27 #define MMS114_X_RESOLUTION 0x03 28 #define MMS114_Y_RESOLUTION 0x04 29 #define MMS114_CONTACT_THRESHOLD 0x05 30 #define MMS114_MOVING_THRESHOLD 0x06 31 32 /* Read only registers */ 33 #define MMS114_PACKET_SIZE 0x0F 34 #define MMS114_INFOMATION 0x10 35 #define MMS114_TSP_REV 0xF0 36 37 /* Minimum delay time is 50us between stop and start signal of i2c */ 38 #define MMS114_I2C_DELAY 50 39 40 /* 200ms needs after power on */ 41 #define MMS114_POWERON_DELAY 200 42 43 /* Touchscreen absolute values */ 44 #define MMS114_MAX_AREA 0xff 45 46 #define MMS114_MAX_TOUCH 10 47 #define MMS114_PACKET_NUM 8 48 49 /* Touch type */ 50 #define MMS114_TYPE_NONE 0 51 #define MMS114_TYPE_TOUCHSCREEN 1 52 #define MMS114_TYPE_TOUCHKEY 2 53 54 struct mms114_data { 55 struct i2c_client *client; 56 struct input_dev *input_dev; 57 struct regulator *core_reg; 58 struct regulator *io_reg; 59 const struct mms114_platform_data *pdata; 60 61 /* Use cache data for mode control register(write only) */ 62 u8 cache_mode_control; 63 }; 64 65 struct mms114_touch { 66 u8 id:4, reserved_bit4:1, type:2, pressed:1; 67 u8 x_hi:4, y_hi:4; 68 u8 x_lo; 69 u8 y_lo; 70 u8 width; 71 u8 strength; 72 u8 reserved[2]; 73 } __packed; 74 75 static int __mms114_read_reg(struct mms114_data *data, unsigned int reg, 76 unsigned int len, u8 *val) 77 { 78 struct i2c_client *client = data->client; 79 struct i2c_msg xfer[2]; 80 u8 buf = reg & 0xff; 81 int error; 82 83 if (reg <= MMS114_MODE_CONTROL && reg + len > MMS114_MODE_CONTROL) 84 BUG(); 85 86 /* Write register: use repeated start */ 87 xfer[0].addr = client->addr; 88 xfer[0].flags = I2C_M_TEN | I2C_M_NOSTART; 89 xfer[0].len = 1; 90 xfer[0].buf = &buf; 91 92 /* Read data */ 93 xfer[1].addr = client->addr; 94 xfer[1].flags = I2C_M_RD; 95 xfer[1].len = len; 96 xfer[1].buf = val; 97 98 error = i2c_transfer(client->adapter, xfer, 2); 99 if (error != 2) { 100 dev_err(&client->dev, 101 "%s: i2c transfer failed (%d)\n", __func__, error); 102 return error < 0 ? error : -EIO; 103 } 104 udelay(MMS114_I2C_DELAY); 105 106 return 0; 107 } 108 109 static int mms114_read_reg(struct mms114_data *data, unsigned int reg) 110 { 111 u8 val; 112 int error; 113 114 if (reg == MMS114_MODE_CONTROL) 115 return data->cache_mode_control; 116 117 error = __mms114_read_reg(data, reg, 1, &val); 118 return error < 0 ? error : val; 119 } 120 121 static int mms114_write_reg(struct mms114_data *data, unsigned int reg, 122 unsigned int val) 123 { 124 struct i2c_client *client = data->client; 125 u8 buf[2]; 126 int error; 127 128 buf[0] = reg & 0xff; 129 buf[1] = val & 0xff; 130 131 error = i2c_master_send(client, buf, 2); 132 if (error != 2) { 133 dev_err(&client->dev, 134 "%s: i2c send failed (%d)\n", __func__, error); 135 return error < 0 ? error : -EIO; 136 } 137 udelay(MMS114_I2C_DELAY); 138 139 if (reg == MMS114_MODE_CONTROL) 140 data->cache_mode_control = val; 141 142 return 0; 143 } 144 145 static void mms114_process_mt(struct mms114_data *data, struct mms114_touch *touch) 146 { 147 const struct mms114_platform_data *pdata = data->pdata; 148 struct i2c_client *client = data->client; 149 struct input_dev *input_dev = data->input_dev; 150 unsigned int id; 151 unsigned int x; 152 unsigned int y; 153 154 if (touch->id > MMS114_MAX_TOUCH) { 155 dev_err(&client->dev, "Wrong touch id (%d)\n", touch->id); 156 return; 157 } 158 159 if (touch->type != MMS114_TYPE_TOUCHSCREEN) { 160 dev_err(&client->dev, "Wrong touch type (%d)\n", touch->type); 161 return; 162 } 163 164 id = touch->id - 1; 165 x = touch->x_lo | touch->x_hi << 8; 166 y = touch->y_lo | touch->y_hi << 8; 167 if (x > pdata->x_size || y > pdata->y_size) { 168 dev_dbg(&client->dev, 169 "Wrong touch coordinates (%d, %d)\n", x, y); 170 return; 171 } 172 173 if (pdata->x_invert) 174 x = pdata->x_size - x; 175 if (pdata->y_invert) 176 y = pdata->y_size - y; 177 178 dev_dbg(&client->dev, 179 "id: %d, type: %d, pressed: %d, x: %d, y: %d, width: %d, strength: %d\n", 180 id, touch->type, touch->pressed, 181 x, y, touch->width, touch->strength); 182 183 input_mt_slot(input_dev, id); 184 input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, touch->pressed); 185 186 if (touch->pressed) { 187 input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, touch->width); 188 input_report_abs(input_dev, ABS_MT_POSITION_X, x); 189 input_report_abs(input_dev, ABS_MT_POSITION_Y, y); 190 input_report_abs(input_dev, ABS_MT_PRESSURE, touch->strength); 191 } 192 } 193 194 static irqreturn_t mms114_interrupt(int irq, void *dev_id) 195 { 196 struct mms114_data *data = dev_id; 197 struct input_dev *input_dev = data->input_dev; 198 struct mms114_touch touch[MMS114_MAX_TOUCH]; 199 int packet_size; 200 int touch_size; 201 int index; 202 int error; 203 204 mutex_lock(&input_dev->mutex); 205 if (!input_dev->users) { 206 mutex_unlock(&input_dev->mutex); 207 goto out; 208 } 209 mutex_unlock(&input_dev->mutex); 210 211 packet_size = mms114_read_reg(data, MMS114_PACKET_SIZE); 212 if (packet_size <= 0) 213 goto out; 214 215 touch_size = packet_size / MMS114_PACKET_NUM; 216 217 error = __mms114_read_reg(data, MMS114_INFOMATION, packet_size, 218 (u8 *)touch); 219 if (error < 0) 220 goto out; 221 222 for (index = 0; index < touch_size; index++) 223 mms114_process_mt(data, touch + index); 224 225 input_mt_report_pointer_emulation(data->input_dev, true); 226 input_sync(data->input_dev); 227 228 out: 229 return IRQ_HANDLED; 230 } 231 232 static int mms114_set_active(struct mms114_data *data, bool active) 233 { 234 int val; 235 236 val = mms114_read_reg(data, MMS114_MODE_CONTROL); 237 if (val < 0) 238 return val; 239 240 val &= ~MMS114_OPERATION_MODE_MASK; 241 242 /* If active is false, sleep mode */ 243 if (active) 244 val |= MMS114_ACTIVE; 245 246 return mms114_write_reg(data, MMS114_MODE_CONTROL, val); 247 } 248 249 static int mms114_get_version(struct mms114_data *data) 250 { 251 struct device *dev = &data->client->dev; 252 u8 buf[6]; 253 int error; 254 255 error = __mms114_read_reg(data, MMS114_TSP_REV, 6, buf); 256 if (error < 0) 257 return error; 258 259 dev_info(dev, "TSP Rev: 0x%x, HW Rev: 0x%x, Firmware Ver: 0x%x\n", 260 buf[0], buf[1], buf[3]); 261 262 return 0; 263 } 264 265 static int mms114_setup_regs(struct mms114_data *data) 266 { 267 const struct mms114_platform_data *pdata = data->pdata; 268 int val; 269 int error; 270 271 error = mms114_get_version(data); 272 if (error < 0) 273 return error; 274 275 error = mms114_set_active(data, true); 276 if (error < 0) 277 return error; 278 279 val = (pdata->x_size >> 8) & 0xf; 280 val |= ((pdata->y_size >> 8) & 0xf) << 4; 281 error = mms114_write_reg(data, MMS114_XY_RESOLUTION_H, val); 282 if (error < 0) 283 return error; 284 285 val = pdata->x_size & 0xff; 286 error = mms114_write_reg(data, MMS114_X_RESOLUTION, val); 287 if (error < 0) 288 return error; 289 290 val = pdata->y_size & 0xff; 291 error = mms114_write_reg(data, MMS114_Y_RESOLUTION, val); 292 if (error < 0) 293 return error; 294 295 if (pdata->contact_threshold) { 296 error = mms114_write_reg(data, MMS114_CONTACT_THRESHOLD, 297 pdata->contact_threshold); 298 if (error < 0) 299 return error; 300 } 301 302 if (pdata->moving_threshold) { 303 error = mms114_write_reg(data, MMS114_MOVING_THRESHOLD, 304 pdata->moving_threshold); 305 if (error < 0) 306 return error; 307 } 308 309 return 0; 310 } 311 312 static int mms114_start(struct mms114_data *data) 313 { 314 struct i2c_client *client = data->client; 315 int error; 316 317 if (data->core_reg) 318 regulator_enable(data->core_reg); 319 if (data->io_reg) 320 regulator_enable(data->io_reg); 321 mdelay(MMS114_POWERON_DELAY); 322 323 error = mms114_setup_regs(data); 324 if (error < 0) 325 return error; 326 327 if (data->pdata->cfg_pin) 328 data->pdata->cfg_pin(true); 329 330 enable_irq(client->irq); 331 332 return 0; 333 } 334 335 static void mms114_stop(struct mms114_data *data) 336 { 337 struct i2c_client *client = data->client; 338 339 disable_irq(client->irq); 340 341 if (data->pdata->cfg_pin) 342 data->pdata->cfg_pin(false); 343 344 if (data->io_reg) 345 regulator_disable(data->io_reg); 346 if (data->core_reg) 347 regulator_disable(data->core_reg); 348 } 349 350 static int mms114_input_open(struct input_dev *dev) 351 { 352 struct mms114_data *data = input_get_drvdata(dev); 353 354 return mms114_start(data); 355 } 356 357 static void mms114_input_close(struct input_dev *dev) 358 { 359 struct mms114_data *data = input_get_drvdata(dev); 360 361 mms114_stop(data); 362 } 363 364 #ifdef CONFIG_OF 365 static struct mms114_platform_data *mms114_parse_dt(struct device *dev) 366 { 367 struct mms114_platform_data *pdata; 368 struct device_node *np = dev->of_node; 369 370 if (!np) 371 return NULL; 372 373 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); 374 if (!pdata) { 375 dev_err(dev, "failed to allocate platform data\n"); 376 return NULL; 377 } 378 379 if (of_property_read_u32(np, "x-size", &pdata->x_size)) { 380 dev_err(dev, "failed to get x-size property\n"); 381 return NULL; 382 }; 383 384 if (of_property_read_u32(np, "y-size", &pdata->y_size)) { 385 dev_err(dev, "failed to get y-size property\n"); 386 return NULL; 387 }; 388 389 of_property_read_u32(np, "contact-threshold", 390 &pdata->contact_threshold); 391 of_property_read_u32(np, "moving-threshold", 392 &pdata->moving_threshold); 393 394 if (of_find_property(np, "x-invert", NULL)) 395 pdata->x_invert = true; 396 if (of_find_property(np, "y-invert", NULL)) 397 pdata->y_invert = true; 398 399 return pdata; 400 } 401 #else 402 static inline struct mms114_platform_data *mms114_parse_dt(struct device *dev) 403 { 404 return NULL; 405 } 406 #endif 407 408 static int mms114_probe(struct i2c_client *client, 409 const struct i2c_device_id *id) 410 { 411 const struct mms114_platform_data *pdata; 412 struct mms114_data *data; 413 struct input_dev *input_dev; 414 int error; 415 416 pdata = dev_get_platdata(&client->dev); 417 if (!pdata) 418 pdata = mms114_parse_dt(&client->dev); 419 420 if (!pdata) { 421 dev_err(&client->dev, "Need platform data\n"); 422 return -EINVAL; 423 } 424 425 if (!i2c_check_functionality(client->adapter, 426 I2C_FUNC_PROTOCOL_MANGLING)) { 427 dev_err(&client->dev, 428 "Need i2c bus that supports protocol mangling\n"); 429 return -ENODEV; 430 } 431 432 data = devm_kzalloc(&client->dev, sizeof(struct mms114_data), 433 GFP_KERNEL); 434 input_dev = devm_input_allocate_device(&client->dev); 435 if (!data || !input_dev) { 436 dev_err(&client->dev, "Failed to allocate memory\n"); 437 return -ENOMEM; 438 } 439 440 data->client = client; 441 data->input_dev = input_dev; 442 data->pdata = pdata; 443 444 input_dev->name = "MELPAS MMS114 Touchscreen"; 445 input_dev->id.bustype = BUS_I2C; 446 input_dev->dev.parent = &client->dev; 447 input_dev->open = mms114_input_open; 448 input_dev->close = mms114_input_close; 449 450 __set_bit(EV_ABS, input_dev->evbit); 451 __set_bit(EV_KEY, input_dev->evbit); 452 __set_bit(BTN_TOUCH, input_dev->keybit); 453 input_set_abs_params(input_dev, ABS_X, 0, data->pdata->x_size, 0, 0); 454 input_set_abs_params(input_dev, ABS_Y, 0, data->pdata->y_size, 0, 0); 455 456 /* For multi touch */ 457 input_mt_init_slots(input_dev, MMS114_MAX_TOUCH, 0); 458 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 459 0, MMS114_MAX_AREA, 0, 0); 460 input_set_abs_params(input_dev, ABS_MT_POSITION_X, 461 0, data->pdata->x_size, 0, 0); 462 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 463 0, data->pdata->y_size, 0, 0); 464 input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 255, 0, 0); 465 466 input_set_drvdata(input_dev, data); 467 i2c_set_clientdata(client, data); 468 469 data->core_reg = devm_regulator_get(&client->dev, "avdd"); 470 if (IS_ERR(data->core_reg)) { 471 error = PTR_ERR(data->core_reg); 472 dev_err(&client->dev, 473 "Unable to get the Core regulator (%d)\n", error); 474 return error; 475 } 476 477 data->io_reg = devm_regulator_get(&client->dev, "vdd"); 478 if (IS_ERR(data->io_reg)) { 479 error = PTR_ERR(data->io_reg); 480 dev_err(&client->dev, 481 "Unable to get the IO regulator (%d)\n", error); 482 return error; 483 } 484 485 error = devm_request_threaded_irq(&client->dev, client->irq, NULL, 486 mms114_interrupt, IRQF_TRIGGER_FALLING | IRQF_ONESHOT, 487 dev_name(&client->dev), data); 488 if (error) { 489 dev_err(&client->dev, "Failed to register interrupt\n"); 490 return error; 491 } 492 disable_irq(client->irq); 493 494 error = input_register_device(data->input_dev); 495 if (error) { 496 dev_err(&client->dev, "Failed to register input device\n"); 497 return error; 498 } 499 500 return 0; 501 } 502 503 #ifdef CONFIG_PM_SLEEP 504 static int mms114_suspend(struct device *dev) 505 { 506 struct i2c_client *client = to_i2c_client(dev); 507 struct mms114_data *data = i2c_get_clientdata(client); 508 struct input_dev *input_dev = data->input_dev; 509 int id; 510 511 /* Release all touch */ 512 for (id = 0; id < MMS114_MAX_TOUCH; id++) { 513 input_mt_slot(input_dev, id); 514 input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, false); 515 } 516 517 input_mt_report_pointer_emulation(input_dev, true); 518 input_sync(input_dev); 519 520 mutex_lock(&input_dev->mutex); 521 if (input_dev->users) 522 mms114_stop(data); 523 mutex_unlock(&input_dev->mutex); 524 525 return 0; 526 } 527 528 static int mms114_resume(struct device *dev) 529 { 530 struct i2c_client *client = to_i2c_client(dev); 531 struct mms114_data *data = i2c_get_clientdata(client); 532 struct input_dev *input_dev = data->input_dev; 533 int error; 534 535 mutex_lock(&input_dev->mutex); 536 if (input_dev->users) { 537 error = mms114_start(data); 538 if (error < 0) { 539 mutex_unlock(&input_dev->mutex); 540 return error; 541 } 542 } 543 mutex_unlock(&input_dev->mutex); 544 545 return 0; 546 } 547 #endif 548 549 static SIMPLE_DEV_PM_OPS(mms114_pm_ops, mms114_suspend, mms114_resume); 550 551 static const struct i2c_device_id mms114_id[] = { 552 { "mms114", 0 }, 553 { } 554 }; 555 MODULE_DEVICE_TABLE(i2c, mms114_id); 556 557 #ifdef CONFIG_OF 558 static struct of_device_id mms114_dt_match[] = { 559 { .compatible = "melfas,mms114" }, 560 { } 561 }; 562 #endif 563 564 static struct i2c_driver mms114_driver = { 565 .driver = { 566 .name = "mms114", 567 .owner = THIS_MODULE, 568 .pm = &mms114_pm_ops, 569 .of_match_table = of_match_ptr(mms114_dt_match), 570 }, 571 .probe = mms114_probe, 572 .id_table = mms114_id, 573 }; 574 575 module_i2c_driver(mms114_driver); 576 577 /* Module information */ 578 MODULE_AUTHOR("Joonyoung Shim <jy0922.shim@samsung.com>"); 579 MODULE_DESCRIPTION("MELFAS mms114 Touchscreen driver"); 580 MODULE_LICENSE("GPL"); 581