1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Input driver for Microchip CAP11xx based capacitive touch sensors 4 * 5 * (c) 2014 Daniel Mack <linux@zonque.org> 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/module.h> 10 #include <linux/interrupt.h> 11 #include <linux/input.h> 12 #include <linux/leds.h> 13 #include <linux/of_irq.h> 14 #include <linux/regmap.h> 15 #include <linux/i2c.h> 16 #include <linux/gpio/consumer.h> 17 18 #define CAP11XX_REG_MAIN_CONTROL 0x00 19 #define CAP11XX_REG_MAIN_CONTROL_GAIN_SHIFT (6) 20 #define CAP11XX_REG_MAIN_CONTROL_GAIN_MASK (0xc0) 21 #define CAP11XX_REG_MAIN_CONTROL_DLSEEP BIT(4) 22 #define CAP11XX_REG_GENERAL_STATUS 0x02 23 #define CAP11XX_REG_SENSOR_INPUT 0x03 24 #define CAP11XX_REG_NOISE_FLAG_STATUS 0x0a 25 #define CAP11XX_REG_SENOR_DELTA(X) (0x10 + (X)) 26 #define CAP11XX_REG_SENSITIVITY_CONTROL 0x1f 27 #define CAP11XX_REG_CONFIG 0x20 28 #define CAP11XX_REG_SENSOR_ENABLE 0x21 29 #define CAP11XX_REG_SENSOR_CONFIG 0x22 30 #define CAP11XX_REG_SENSOR_CONFIG2 0x23 31 #define CAP11XX_REG_SAMPLING_CONFIG 0x24 32 #define CAP11XX_REG_CALIBRATION 0x26 33 #define CAP11XX_REG_INT_ENABLE 0x27 34 #define CAP11XX_REG_REPEAT_RATE 0x28 35 #define CAP11XX_REG_MT_CONFIG 0x2a 36 #define CAP11XX_REG_MT_PATTERN_CONFIG 0x2b 37 #define CAP11XX_REG_MT_PATTERN 0x2d 38 #define CAP11XX_REG_RECALIB_CONFIG 0x2f 39 #define CAP11XX_REG_SENSOR_THRESH(X) (0x30 + (X)) 40 #define CAP11XX_REG_SENSOR_NOISE_THRESH 0x38 41 #define CAP11XX_REG_STANDBY_CHANNEL 0x40 42 #define CAP11XX_REG_STANDBY_CONFIG 0x41 43 #define CAP11XX_REG_STANDBY_SENSITIVITY 0x42 44 #define CAP11XX_REG_STANDBY_THRESH 0x43 45 #define CAP11XX_REG_CONFIG2 0x44 46 #define CAP11XX_REG_CONFIG2_ALT_POL BIT(6) 47 #define CAP11XX_REG_SENSOR_BASE_CNT(X) (0x50 + (X)) 48 #define CAP11XX_REG_LED_POLARITY 0x73 49 #define CAP11XX_REG_LED_OUTPUT_CONTROL 0x74 50 51 #define CAP11XX_REG_LED_DUTY_CYCLE_1 0x90 52 #define CAP11XX_REG_LED_DUTY_CYCLE_2 0x91 53 #define CAP11XX_REG_LED_DUTY_CYCLE_3 0x92 54 #define CAP11XX_REG_LED_DUTY_CYCLE_4 0x93 55 56 #define CAP11XX_REG_LED_DUTY_MIN_MASK (0x0f) 57 #define CAP11XX_REG_LED_DUTY_MIN_MASK_SHIFT (0) 58 #define CAP11XX_REG_LED_DUTY_MAX_MASK (0xf0) 59 #define CAP11XX_REG_LED_DUTY_MAX_MASK_SHIFT (4) 60 #define CAP11XX_REG_LED_DUTY_MAX_VALUE (15) 61 62 #define CAP11XX_REG_SENSOR_CALIB (0xb1 + (X)) 63 #define CAP11XX_REG_SENSOR_CALIB_LSB1 0xb9 64 #define CAP11XX_REG_SENSOR_CALIB_LSB2 0xba 65 #define CAP11XX_REG_PRODUCT_ID 0xfd 66 #define CAP11XX_REG_MANUFACTURER_ID 0xfe 67 #define CAP11XX_REG_REVISION 0xff 68 69 #define CAP11XX_MANUFACTURER_ID 0x5d 70 71 #ifdef CONFIG_LEDS_CLASS 72 struct cap11xx_led { 73 struct cap11xx_priv *priv; 74 struct led_classdev cdev; 75 u32 reg; 76 }; 77 #endif 78 79 struct cap11xx_priv { 80 struct regmap *regmap; 81 struct input_dev *idev; 82 83 struct cap11xx_led *leds; 84 int num_leds; 85 86 /* config */ 87 u32 keycodes[]; 88 }; 89 90 struct cap11xx_hw_model { 91 u8 product_id; 92 unsigned int num_channels; 93 unsigned int num_leds; 94 bool no_gain; 95 }; 96 97 enum { 98 CAP1106, 99 CAP1126, 100 CAP1188, 101 CAP1203, 102 CAP1206, 103 CAP1293, 104 CAP1298 105 }; 106 107 static const struct cap11xx_hw_model cap11xx_devices[] = { 108 [CAP1106] = { .product_id = 0x55, .num_channels = 6, .num_leds = 0, .no_gain = false }, 109 [CAP1126] = { .product_id = 0x53, .num_channels = 6, .num_leds = 2, .no_gain = false }, 110 [CAP1188] = { .product_id = 0x50, .num_channels = 8, .num_leds = 8, .no_gain = false }, 111 [CAP1203] = { .product_id = 0x6d, .num_channels = 3, .num_leds = 0, .no_gain = true }, 112 [CAP1206] = { .product_id = 0x67, .num_channels = 6, .num_leds = 0, .no_gain = true }, 113 [CAP1293] = { .product_id = 0x6f, .num_channels = 3, .num_leds = 0, .no_gain = false }, 114 [CAP1298] = { .product_id = 0x71, .num_channels = 8, .num_leds = 0, .no_gain = false }, 115 }; 116 117 static const struct reg_default cap11xx_reg_defaults[] = { 118 { CAP11XX_REG_MAIN_CONTROL, 0x00 }, 119 { CAP11XX_REG_GENERAL_STATUS, 0x00 }, 120 { CAP11XX_REG_SENSOR_INPUT, 0x00 }, 121 { CAP11XX_REG_NOISE_FLAG_STATUS, 0x00 }, 122 { CAP11XX_REG_SENSITIVITY_CONTROL, 0x2f }, 123 { CAP11XX_REG_CONFIG, 0x20 }, 124 { CAP11XX_REG_SENSOR_ENABLE, 0x3f }, 125 { CAP11XX_REG_SENSOR_CONFIG, 0xa4 }, 126 { CAP11XX_REG_SENSOR_CONFIG2, 0x07 }, 127 { CAP11XX_REG_SAMPLING_CONFIG, 0x39 }, 128 { CAP11XX_REG_CALIBRATION, 0x00 }, 129 { CAP11XX_REG_INT_ENABLE, 0x3f }, 130 { CAP11XX_REG_REPEAT_RATE, 0x3f }, 131 { CAP11XX_REG_MT_CONFIG, 0x80 }, 132 { CAP11XX_REG_MT_PATTERN_CONFIG, 0x00 }, 133 { CAP11XX_REG_MT_PATTERN, 0x3f }, 134 { CAP11XX_REG_RECALIB_CONFIG, 0x8a }, 135 { CAP11XX_REG_SENSOR_THRESH(0), 0x40 }, 136 { CAP11XX_REG_SENSOR_THRESH(1), 0x40 }, 137 { CAP11XX_REG_SENSOR_THRESH(2), 0x40 }, 138 { CAP11XX_REG_SENSOR_THRESH(3), 0x40 }, 139 { CAP11XX_REG_SENSOR_THRESH(4), 0x40 }, 140 { CAP11XX_REG_SENSOR_THRESH(5), 0x40 }, 141 { CAP11XX_REG_SENSOR_NOISE_THRESH, 0x01 }, 142 { CAP11XX_REG_STANDBY_CHANNEL, 0x00 }, 143 { CAP11XX_REG_STANDBY_CONFIG, 0x39 }, 144 { CAP11XX_REG_STANDBY_SENSITIVITY, 0x02 }, 145 { CAP11XX_REG_STANDBY_THRESH, 0x40 }, 146 { CAP11XX_REG_CONFIG2, 0x40 }, 147 { CAP11XX_REG_LED_POLARITY, 0x00 }, 148 { CAP11XX_REG_SENSOR_CALIB_LSB1, 0x00 }, 149 { CAP11XX_REG_SENSOR_CALIB_LSB2, 0x00 }, 150 }; 151 152 static bool cap11xx_volatile_reg(struct device *dev, unsigned int reg) 153 { 154 switch (reg) { 155 case CAP11XX_REG_MAIN_CONTROL: 156 case CAP11XX_REG_SENSOR_INPUT: 157 case CAP11XX_REG_SENOR_DELTA(0): 158 case CAP11XX_REG_SENOR_DELTA(1): 159 case CAP11XX_REG_SENOR_DELTA(2): 160 case CAP11XX_REG_SENOR_DELTA(3): 161 case CAP11XX_REG_SENOR_DELTA(4): 162 case CAP11XX_REG_SENOR_DELTA(5): 163 case CAP11XX_REG_PRODUCT_ID: 164 case CAP11XX_REG_MANUFACTURER_ID: 165 case CAP11XX_REG_REVISION: 166 return true; 167 } 168 169 return false; 170 } 171 172 static const struct regmap_config cap11xx_regmap_config = { 173 .reg_bits = 8, 174 .val_bits = 8, 175 176 .max_register = CAP11XX_REG_REVISION, 177 .reg_defaults = cap11xx_reg_defaults, 178 179 .num_reg_defaults = ARRAY_SIZE(cap11xx_reg_defaults), 180 .cache_type = REGCACHE_RBTREE, 181 .volatile_reg = cap11xx_volatile_reg, 182 }; 183 184 static irqreturn_t cap11xx_thread_func(int irq_num, void *data) 185 { 186 struct cap11xx_priv *priv = data; 187 unsigned int status; 188 int ret, i; 189 190 /* 191 * Deassert interrupt. This needs to be done before reading the status 192 * registers, which will not carry valid values otherwise. 193 */ 194 ret = regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL, 1, 0); 195 if (ret < 0) 196 goto out; 197 198 ret = regmap_read(priv->regmap, CAP11XX_REG_SENSOR_INPUT, &status); 199 if (ret < 0) 200 goto out; 201 202 for (i = 0; i < priv->idev->keycodemax; i++) 203 input_report_key(priv->idev, priv->keycodes[i], 204 status & (1 << i)); 205 206 input_sync(priv->idev); 207 208 out: 209 return IRQ_HANDLED; 210 } 211 212 static int cap11xx_set_sleep(struct cap11xx_priv *priv, bool sleep) 213 { 214 /* 215 * DLSEEP mode will turn off all LEDS, prevent this 216 */ 217 if (IS_ENABLED(CONFIG_LEDS_CLASS) && priv->num_leds) 218 return 0; 219 220 return regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL, 221 CAP11XX_REG_MAIN_CONTROL_DLSEEP, 222 sleep ? CAP11XX_REG_MAIN_CONTROL_DLSEEP : 0); 223 } 224 225 static int cap11xx_input_open(struct input_dev *idev) 226 { 227 struct cap11xx_priv *priv = input_get_drvdata(idev); 228 229 return cap11xx_set_sleep(priv, false); 230 } 231 232 static void cap11xx_input_close(struct input_dev *idev) 233 { 234 struct cap11xx_priv *priv = input_get_drvdata(idev); 235 236 cap11xx_set_sleep(priv, true); 237 } 238 239 #ifdef CONFIG_LEDS_CLASS 240 static int cap11xx_led_set(struct led_classdev *cdev, 241 enum led_brightness value) 242 { 243 struct cap11xx_led *led = container_of(cdev, struct cap11xx_led, cdev); 244 struct cap11xx_priv *priv = led->priv; 245 246 /* 247 * All LEDs share the same duty cycle as this is a HW 248 * limitation. Brightness levels per LED are either 249 * 0 (OFF) and 1 (ON). 250 */ 251 return regmap_update_bits(priv->regmap, 252 CAP11XX_REG_LED_OUTPUT_CONTROL, 253 BIT(led->reg), 254 value ? BIT(led->reg) : 0); 255 } 256 257 static int cap11xx_init_leds(struct device *dev, 258 struct cap11xx_priv *priv, int num_leds) 259 { 260 struct device_node *node = dev->of_node, *child; 261 struct cap11xx_led *led; 262 int cnt = of_get_child_count(node); 263 int error; 264 265 if (!num_leds || !cnt) 266 return 0; 267 268 if (cnt > num_leds) 269 return -EINVAL; 270 271 led = devm_kcalloc(dev, cnt, sizeof(struct cap11xx_led), GFP_KERNEL); 272 if (!led) 273 return -ENOMEM; 274 275 priv->leds = led; 276 277 error = regmap_update_bits(priv->regmap, 278 CAP11XX_REG_LED_OUTPUT_CONTROL, 0xff, 0); 279 if (error) 280 return error; 281 282 error = regmap_update_bits(priv->regmap, CAP11XX_REG_LED_DUTY_CYCLE_4, 283 CAP11XX_REG_LED_DUTY_MAX_MASK, 284 CAP11XX_REG_LED_DUTY_MAX_VALUE << 285 CAP11XX_REG_LED_DUTY_MAX_MASK_SHIFT); 286 if (error) 287 return error; 288 289 for_each_child_of_node(node, child) { 290 u32 reg; 291 292 led->cdev.name = 293 of_get_property(child, "label", NULL) ? : child->name; 294 led->cdev.default_trigger = 295 of_get_property(child, "linux,default-trigger", NULL); 296 led->cdev.flags = 0; 297 led->cdev.brightness_set_blocking = cap11xx_led_set; 298 led->cdev.max_brightness = 1; 299 led->cdev.brightness = LED_OFF; 300 301 error = of_property_read_u32(child, "reg", ®); 302 if (error != 0 || reg >= num_leds) { 303 of_node_put(child); 304 return -EINVAL; 305 } 306 307 led->reg = reg; 308 led->priv = priv; 309 310 error = devm_led_classdev_register(dev, &led->cdev); 311 if (error) { 312 of_node_put(child); 313 return error; 314 } 315 316 priv->num_leds++; 317 led++; 318 } 319 320 return 0; 321 } 322 #else 323 static int cap11xx_init_leds(struct device *dev, 324 struct cap11xx_priv *priv, int num_leds) 325 { 326 return 0; 327 } 328 #endif 329 330 static int cap11xx_i2c_probe(struct i2c_client *i2c_client) 331 { 332 const struct i2c_device_id *id = i2c_client_get_device_id(i2c_client); 333 struct device *dev = &i2c_client->dev; 334 struct cap11xx_priv *priv; 335 struct device_node *node; 336 const struct cap11xx_hw_model *cap; 337 int i, error, irq, gain = 0; 338 unsigned int val, rev; 339 u32 gain32; 340 341 if (id->driver_data >= ARRAY_SIZE(cap11xx_devices)) { 342 dev_err(dev, "Invalid device ID %lu\n", id->driver_data); 343 return -EINVAL; 344 } 345 346 cap = &cap11xx_devices[id->driver_data]; 347 if (!cap || !cap->num_channels) { 348 dev_err(dev, "Invalid device configuration\n"); 349 return -EINVAL; 350 } 351 352 priv = devm_kzalloc(dev, 353 struct_size(priv, keycodes, cap->num_channels), 354 GFP_KERNEL); 355 if (!priv) 356 return -ENOMEM; 357 358 priv->regmap = devm_regmap_init_i2c(i2c_client, &cap11xx_regmap_config); 359 if (IS_ERR(priv->regmap)) 360 return PTR_ERR(priv->regmap); 361 362 error = regmap_read(priv->regmap, CAP11XX_REG_PRODUCT_ID, &val); 363 if (error) 364 return error; 365 366 if (val != cap->product_id) { 367 dev_err(dev, "Product ID: Got 0x%02x, expected 0x%02x\n", 368 val, cap->product_id); 369 return -ENXIO; 370 } 371 372 error = regmap_read(priv->regmap, CAP11XX_REG_MANUFACTURER_ID, &val); 373 if (error) 374 return error; 375 376 if (val != CAP11XX_MANUFACTURER_ID) { 377 dev_err(dev, "Manufacturer ID: Got 0x%02x, expected 0x%02x\n", 378 val, CAP11XX_MANUFACTURER_ID); 379 return -ENXIO; 380 } 381 382 error = regmap_read(priv->regmap, CAP11XX_REG_REVISION, &rev); 383 if (error < 0) 384 return error; 385 386 dev_info(dev, "CAP11XX detected, model %s, revision 0x%02x\n", 387 id->name, rev); 388 node = dev->of_node; 389 390 if (!of_property_read_u32(node, "microchip,sensor-gain", &gain32)) { 391 if (cap->no_gain) 392 dev_warn(dev, 393 "This version doesn't support sensor gain\n"); 394 else if (is_power_of_2(gain32) && gain32 <= 8) 395 gain = ilog2(gain32); 396 else 397 dev_err(dev, "Invalid sensor-gain value %d\n", gain32); 398 } 399 400 if (id->driver_data == CAP1106 || 401 id->driver_data == CAP1126 || 402 id->driver_data == CAP1188) { 403 if (of_property_read_bool(node, "microchip,irq-active-high")) { 404 error = regmap_update_bits(priv->regmap, 405 CAP11XX_REG_CONFIG2, 406 CAP11XX_REG_CONFIG2_ALT_POL, 407 0); 408 if (error) 409 return error; 410 } 411 } 412 413 /* Provide some useful defaults */ 414 for (i = 0; i < cap->num_channels; i++) 415 priv->keycodes[i] = KEY_A + i; 416 417 of_property_read_u32_array(node, "linux,keycodes", 418 priv->keycodes, cap->num_channels); 419 420 if (!cap->no_gain) { 421 error = regmap_update_bits(priv->regmap, 422 CAP11XX_REG_MAIN_CONTROL, 423 CAP11XX_REG_MAIN_CONTROL_GAIN_MASK, 424 gain << CAP11XX_REG_MAIN_CONTROL_GAIN_SHIFT); 425 if (error) 426 return error; 427 } 428 429 /* Disable autorepeat. The Linux input system has its own handling. */ 430 error = regmap_write(priv->regmap, CAP11XX_REG_REPEAT_RATE, 0); 431 if (error) 432 return error; 433 434 priv->idev = devm_input_allocate_device(dev); 435 if (!priv->idev) 436 return -ENOMEM; 437 438 priv->idev->name = "CAP11XX capacitive touch sensor"; 439 priv->idev->id.bustype = BUS_I2C; 440 priv->idev->evbit[0] = BIT_MASK(EV_KEY); 441 442 if (of_property_read_bool(node, "autorepeat")) 443 __set_bit(EV_REP, priv->idev->evbit); 444 445 for (i = 0; i < cap->num_channels; i++) 446 __set_bit(priv->keycodes[i], priv->idev->keybit); 447 448 __clear_bit(KEY_RESERVED, priv->idev->keybit); 449 450 priv->idev->keycode = priv->keycodes; 451 priv->idev->keycodesize = sizeof(priv->keycodes[0]); 452 priv->idev->keycodemax = cap->num_channels; 453 454 priv->idev->id.vendor = CAP11XX_MANUFACTURER_ID; 455 priv->idev->id.product = cap->product_id; 456 priv->idev->id.version = rev; 457 458 priv->idev->open = cap11xx_input_open; 459 priv->idev->close = cap11xx_input_close; 460 461 error = cap11xx_init_leds(dev, priv, cap->num_leds); 462 if (error) 463 return error; 464 465 input_set_drvdata(priv->idev, priv); 466 467 /* 468 * Put the device in deep sleep mode for now. 469 * ->open() will bring it back once the it is actually needed. 470 */ 471 cap11xx_set_sleep(priv, true); 472 473 error = input_register_device(priv->idev); 474 if (error) 475 return error; 476 477 irq = irq_of_parse_and_map(node, 0); 478 if (!irq) { 479 dev_err(dev, "Unable to parse or map IRQ\n"); 480 return -ENXIO; 481 } 482 483 error = devm_request_threaded_irq(dev, irq, NULL, cap11xx_thread_func, 484 IRQF_ONESHOT, dev_name(dev), priv); 485 if (error) 486 return error; 487 488 return 0; 489 } 490 491 static const struct of_device_id cap11xx_dt_ids[] = { 492 { .compatible = "microchip,cap1106", }, 493 { .compatible = "microchip,cap1126", }, 494 { .compatible = "microchip,cap1188", }, 495 { .compatible = "microchip,cap1203", }, 496 { .compatible = "microchip,cap1206", }, 497 { .compatible = "microchip,cap1293", }, 498 { .compatible = "microchip,cap1298", }, 499 {} 500 }; 501 MODULE_DEVICE_TABLE(of, cap11xx_dt_ids); 502 503 static const struct i2c_device_id cap11xx_i2c_ids[] = { 504 { "cap1106", CAP1106 }, 505 { "cap1126", CAP1126 }, 506 { "cap1188", CAP1188 }, 507 { "cap1203", CAP1203 }, 508 { "cap1206", CAP1206 }, 509 { "cap1293", CAP1293 }, 510 { "cap1298", CAP1298 }, 511 {} 512 }; 513 MODULE_DEVICE_TABLE(i2c, cap11xx_i2c_ids); 514 515 static struct i2c_driver cap11xx_i2c_driver = { 516 .driver = { 517 .name = "cap11xx", 518 .of_match_table = cap11xx_dt_ids, 519 }, 520 .id_table = cap11xx_i2c_ids, 521 .probe_new = cap11xx_i2c_probe, 522 }; 523 524 module_i2c_driver(cap11xx_i2c_driver); 525 526 MODULE_DESCRIPTION("Microchip CAP11XX driver"); 527 MODULE_AUTHOR("Daniel Mack <linux@zonque.org>"); 528 MODULE_LICENSE("GPL v2"); 529