1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * 4 * TWL4030 MADC module driver-This driver monitors the real time 5 * conversion of analog signals like battery temperature, 6 * battery type, battery level etc. 7 * 8 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/ 9 * J Keerthy <j-keerthy@ti.com> 10 * 11 * Based on twl4030-madc.c 12 * Copyright (C) 2008 Nokia Corporation 13 * Mikko Ylinen <mikko.k.ylinen@nokia.com> 14 * 15 * Amit Kucheria <amit.kucheria@canonical.com> 16 */ 17 18 #include <linux/device.h> 19 #include <linux/interrupt.h> 20 #include <linux/kernel.h> 21 #include <linux/delay.h> 22 #include <linux/platform_device.h> 23 #include <linux/slab.h> 24 #include <linux/mfd/twl.h> 25 #include <linux/module.h> 26 #include <linux/stddef.h> 27 #include <linux/mutex.h> 28 #include <linux/bitops.h> 29 #include <linux/jiffies.h> 30 #include <linux/types.h> 31 #include <linux/gfp.h> 32 #include <linux/err.h> 33 #include <linux/regulator/consumer.h> 34 35 #include <linux/iio/iio.h> 36 37 #define TWL4030_MADC_MAX_CHANNELS 16 38 39 #define TWL4030_MADC_CTRL1 0x00 40 #define TWL4030_MADC_CTRL2 0x01 41 42 #define TWL4030_MADC_RTSELECT_LSB 0x02 43 #define TWL4030_MADC_SW1SELECT_LSB 0x06 44 #define TWL4030_MADC_SW2SELECT_LSB 0x0A 45 46 #define TWL4030_MADC_RTAVERAGE_LSB 0x04 47 #define TWL4030_MADC_SW1AVERAGE_LSB 0x08 48 #define TWL4030_MADC_SW2AVERAGE_LSB 0x0C 49 50 #define TWL4030_MADC_CTRL_SW1 0x12 51 #define TWL4030_MADC_CTRL_SW2 0x13 52 53 #define TWL4030_MADC_RTCH0_LSB 0x17 54 #define TWL4030_MADC_GPCH0_LSB 0x37 55 56 #define TWL4030_MADC_MADCON (1 << 0) /* MADC power on */ 57 #define TWL4030_MADC_BUSY (1 << 0) /* MADC busy */ 58 /* MADC conversion completion */ 59 #define TWL4030_MADC_EOC_SW (1 << 1) 60 /* MADC SWx start conversion */ 61 #define TWL4030_MADC_SW_START (1 << 5) 62 #define TWL4030_MADC_ADCIN0 (1 << 0) 63 #define TWL4030_MADC_ADCIN1 (1 << 1) 64 #define TWL4030_MADC_ADCIN2 (1 << 2) 65 #define TWL4030_MADC_ADCIN3 (1 << 3) 66 #define TWL4030_MADC_ADCIN4 (1 << 4) 67 #define TWL4030_MADC_ADCIN5 (1 << 5) 68 #define TWL4030_MADC_ADCIN6 (1 << 6) 69 #define TWL4030_MADC_ADCIN7 (1 << 7) 70 #define TWL4030_MADC_ADCIN8 (1 << 8) 71 #define TWL4030_MADC_ADCIN9 (1 << 9) 72 #define TWL4030_MADC_ADCIN10 (1 << 10) 73 #define TWL4030_MADC_ADCIN11 (1 << 11) 74 #define TWL4030_MADC_ADCIN12 (1 << 12) 75 #define TWL4030_MADC_ADCIN13 (1 << 13) 76 #define TWL4030_MADC_ADCIN14 (1 << 14) 77 #define TWL4030_MADC_ADCIN15 (1 << 15) 78 79 /* Fixed channels */ 80 #define TWL4030_MADC_BTEMP TWL4030_MADC_ADCIN1 81 #define TWL4030_MADC_VBUS TWL4030_MADC_ADCIN8 82 #define TWL4030_MADC_VBKB TWL4030_MADC_ADCIN9 83 #define TWL4030_MADC_ICHG TWL4030_MADC_ADCIN10 84 #define TWL4030_MADC_VCHG TWL4030_MADC_ADCIN11 85 #define TWL4030_MADC_VBAT TWL4030_MADC_ADCIN12 86 87 /* Step size and prescaler ratio */ 88 #define TEMP_STEP_SIZE 147 89 #define TEMP_PSR_R 100 90 #define CURR_STEP_SIZE 147 91 #define CURR_PSR_R1 44 92 #define CURR_PSR_R2 88 93 94 #define TWL4030_BCI_BCICTL1 0x23 95 #define TWL4030_BCI_CGAIN 0x020 96 #define TWL4030_BCI_MESBAT (1 << 1) 97 #define TWL4030_BCI_TYPEN (1 << 4) 98 #define TWL4030_BCI_ITHEN (1 << 3) 99 100 #define REG_BCICTL2 0x024 101 #define TWL4030_BCI_ITHSENS 0x007 102 103 /* Register and bits for GPBR1 register */ 104 #define TWL4030_REG_GPBR1 0x0c 105 #define TWL4030_GPBR1_MADC_HFCLK_EN (1 << 7) 106 107 #define TWL4030_USB_SEL_MADC_MCPC (1<<3) 108 #define TWL4030_USB_CARKIT_ANA_CTRL 0xBB 109 110 struct twl4030_madc_conversion_method { 111 u8 sel; 112 u8 avg; 113 u8 rbase; 114 u8 ctrl; 115 }; 116 117 /** 118 * struct twl4030_madc_request - madc request packet for channel conversion 119 * @channels: 16 bit bitmap for individual channels 120 * @do_avg: sample the input channel for 4 consecutive cycles 121 * @method: RT, SW1, SW2 122 * @type: Polling or interrupt based method 123 * @active: Flag if request is active 124 * @result_pending: Flag from irq handler, that result is ready 125 * @raw: Return raw value, do not convert it 126 * @rbuf: Result buffer 127 */ 128 struct twl4030_madc_request { 129 unsigned long channels; 130 bool do_avg; 131 u16 method; 132 u16 type; 133 bool active; 134 bool result_pending; 135 bool raw; 136 int rbuf[TWL4030_MADC_MAX_CHANNELS]; 137 }; 138 139 enum conversion_methods { 140 TWL4030_MADC_RT, 141 TWL4030_MADC_SW1, 142 TWL4030_MADC_SW2, 143 TWL4030_MADC_NUM_METHODS 144 }; 145 146 enum sample_type { 147 TWL4030_MADC_WAIT, 148 TWL4030_MADC_IRQ_ONESHOT, 149 TWL4030_MADC_IRQ_REARM 150 }; 151 152 /** 153 * struct twl4030_madc_data - a container for madc info 154 * @dev: Pointer to device structure for madc 155 * @lock: Mutex protecting this data structure 156 * @regulator: Pointer to bias regulator for madc 157 * @requests: Array of request struct corresponding to SW1, SW2 and RT 158 * @use_second_irq: IRQ selection (main or co-processor) 159 * @imr: Interrupt mask register of MADC 160 * @isr: Interrupt status register of MADC 161 */ 162 struct twl4030_madc_data { 163 struct device *dev; 164 struct mutex lock; /* mutex protecting this data structure */ 165 struct regulator *usb3v1; 166 struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS]; 167 bool use_second_irq; 168 u8 imr; 169 u8 isr; 170 }; 171 172 static int twl4030_madc_conversion(struct twl4030_madc_request *req); 173 174 static int twl4030_madc_read(struct iio_dev *iio_dev, 175 const struct iio_chan_spec *chan, 176 int *val, int *val2, long mask) 177 { 178 struct twl4030_madc_data *madc = iio_priv(iio_dev); 179 struct twl4030_madc_request req; 180 int ret; 181 182 req.method = madc->use_second_irq ? TWL4030_MADC_SW2 : TWL4030_MADC_SW1; 183 184 req.channels = BIT(chan->channel); 185 req.active = false; 186 req.type = TWL4030_MADC_WAIT; 187 req.raw = !(mask == IIO_CHAN_INFO_PROCESSED); 188 req.do_avg = (mask == IIO_CHAN_INFO_AVERAGE_RAW); 189 190 ret = twl4030_madc_conversion(&req); 191 if (ret < 0) 192 return ret; 193 194 *val = req.rbuf[chan->channel]; 195 196 return IIO_VAL_INT; 197 } 198 199 static const struct iio_info twl4030_madc_iio_info = { 200 .read_raw = &twl4030_madc_read, 201 }; 202 203 #define TWL4030_ADC_CHANNEL(_channel, _type, _name) { \ 204 .type = _type, \ 205 .channel = _channel, \ 206 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 207 BIT(IIO_CHAN_INFO_AVERAGE_RAW) | \ 208 BIT(IIO_CHAN_INFO_PROCESSED), \ 209 .datasheet_name = _name, \ 210 .indexed = 1, \ 211 } 212 213 static const struct iio_chan_spec twl4030_madc_iio_channels[] = { 214 TWL4030_ADC_CHANNEL(0, IIO_VOLTAGE, "ADCIN0"), 215 TWL4030_ADC_CHANNEL(1, IIO_TEMP, "ADCIN1"), 216 TWL4030_ADC_CHANNEL(2, IIO_VOLTAGE, "ADCIN2"), 217 TWL4030_ADC_CHANNEL(3, IIO_VOLTAGE, "ADCIN3"), 218 TWL4030_ADC_CHANNEL(4, IIO_VOLTAGE, "ADCIN4"), 219 TWL4030_ADC_CHANNEL(5, IIO_VOLTAGE, "ADCIN5"), 220 TWL4030_ADC_CHANNEL(6, IIO_VOLTAGE, "ADCIN6"), 221 TWL4030_ADC_CHANNEL(7, IIO_VOLTAGE, "ADCIN7"), 222 TWL4030_ADC_CHANNEL(8, IIO_VOLTAGE, "ADCIN8"), 223 TWL4030_ADC_CHANNEL(9, IIO_VOLTAGE, "ADCIN9"), 224 TWL4030_ADC_CHANNEL(10, IIO_CURRENT, "ADCIN10"), 225 TWL4030_ADC_CHANNEL(11, IIO_VOLTAGE, "ADCIN11"), 226 TWL4030_ADC_CHANNEL(12, IIO_VOLTAGE, "ADCIN12"), 227 TWL4030_ADC_CHANNEL(13, IIO_VOLTAGE, "ADCIN13"), 228 TWL4030_ADC_CHANNEL(14, IIO_VOLTAGE, "ADCIN14"), 229 TWL4030_ADC_CHANNEL(15, IIO_VOLTAGE, "ADCIN15"), 230 }; 231 232 static struct twl4030_madc_data *twl4030_madc; 233 234 struct twl4030_prescale_divider_ratios { 235 s16 numerator; 236 s16 denominator; 237 }; 238 239 static const struct twl4030_prescale_divider_ratios 240 twl4030_divider_ratios[16] = { 241 {1, 1}, /* CHANNEL 0 No Prescaler */ 242 {1, 1}, /* CHANNEL 1 No Prescaler */ 243 {6, 10}, /* CHANNEL 2 */ 244 {6, 10}, /* CHANNEL 3 */ 245 {6, 10}, /* CHANNEL 4 */ 246 {6, 10}, /* CHANNEL 5 */ 247 {6, 10}, /* CHANNEL 6 */ 248 {6, 10}, /* CHANNEL 7 */ 249 {3, 14}, /* CHANNEL 8 */ 250 {1, 3}, /* CHANNEL 9 */ 251 {1, 1}, /* CHANNEL 10 No Prescaler */ 252 {15, 100}, /* CHANNEL 11 */ 253 {1, 4}, /* CHANNEL 12 */ 254 {1, 1}, /* CHANNEL 13 Reserved channels */ 255 {1, 1}, /* CHANNEL 14 Reseved channels */ 256 {5, 11}, /* CHANNEL 15 */ 257 }; 258 259 260 /* Conversion table from -3 to 55 degrees Celcius */ 261 static int twl4030_therm_tbl[] = { 262 30800, 29500, 28300, 27100, 263 26000, 24900, 23900, 22900, 22000, 21100, 20300, 19400, 18700, 264 17900, 17200, 16500, 15900, 15300, 14700, 14100, 13600, 13100, 265 12600, 12100, 11600, 11200, 10800, 10400, 10000, 9630, 9280, 266 8950, 8620, 8310, 8020, 7730, 7460, 7200, 6950, 6710, 267 6470, 6250, 6040, 5830, 5640, 5450, 5260, 5090, 4920, 268 4760, 4600, 4450, 4310, 4170, 4040, 3910, 3790, 3670, 269 3550 270 }; 271 272 /* 273 * Structure containing the registers 274 * of different conversion methods supported by MADC. 275 * Hardware or RT real time conversion request initiated by external host 276 * processor for RT Signal conversions. 277 * External host processors can also request for non RT conversions 278 * SW1 and SW2 software conversions also called asynchronous or GPC request. 279 */ 280 static 281 const struct twl4030_madc_conversion_method twl4030_conversion_methods[] = { 282 [TWL4030_MADC_RT] = { 283 .sel = TWL4030_MADC_RTSELECT_LSB, 284 .avg = TWL4030_MADC_RTAVERAGE_LSB, 285 .rbase = TWL4030_MADC_RTCH0_LSB, 286 }, 287 [TWL4030_MADC_SW1] = { 288 .sel = TWL4030_MADC_SW1SELECT_LSB, 289 .avg = TWL4030_MADC_SW1AVERAGE_LSB, 290 .rbase = TWL4030_MADC_GPCH0_LSB, 291 .ctrl = TWL4030_MADC_CTRL_SW1, 292 }, 293 [TWL4030_MADC_SW2] = { 294 .sel = TWL4030_MADC_SW2SELECT_LSB, 295 .avg = TWL4030_MADC_SW2AVERAGE_LSB, 296 .rbase = TWL4030_MADC_GPCH0_LSB, 297 .ctrl = TWL4030_MADC_CTRL_SW2, 298 }, 299 }; 300 301 /** 302 * twl4030_madc_channel_raw_read() - Function to read a particular channel value 303 * @madc: pointer to struct twl4030_madc_data 304 * @reg: lsb of ADC Channel 305 * 306 * Return: 0 on success, an error code otherwise. 307 */ 308 static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg) 309 { 310 u16 val; 311 int ret; 312 /* 313 * For each ADC channel, we have MSB and LSB register pair. MSB address 314 * is always LSB address+1. reg parameter is the address of LSB register 315 */ 316 ret = twl_i2c_read_u16(TWL4030_MODULE_MADC, &val, reg); 317 if (ret) { 318 dev_err(madc->dev, "unable to read register 0x%X\n", reg); 319 return ret; 320 } 321 322 return (int)(val >> 6); 323 } 324 325 /* 326 * Return battery temperature in degrees Celsius 327 * Or < 0 on failure. 328 */ 329 static int twl4030battery_temperature(int raw_volt) 330 { 331 u8 val; 332 int temp, curr, volt, res, ret; 333 334 volt = (raw_volt * TEMP_STEP_SIZE) / TEMP_PSR_R; 335 /* Getting and calculating the supply current in micro amperes */ 336 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, &val, 337 REG_BCICTL2); 338 if (ret < 0) 339 return ret; 340 341 curr = ((val & TWL4030_BCI_ITHSENS) + 1) * 10; 342 /* Getting and calculating the thermistor resistance in ohms */ 343 res = volt * 1000 / curr; 344 /* calculating temperature */ 345 for (temp = 58; temp >= 0; temp--) { 346 int actual = twl4030_therm_tbl[temp]; 347 if ((actual - res) >= 0) 348 break; 349 } 350 351 return temp + 1; 352 } 353 354 static int twl4030battery_current(int raw_volt) 355 { 356 int ret; 357 u8 val; 358 359 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, &val, 360 TWL4030_BCI_BCICTL1); 361 if (ret) 362 return ret; 363 if (val & TWL4030_BCI_CGAIN) /* slope of 0.44 mV/mA */ 364 return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R1; 365 else /* slope of 0.88 mV/mA */ 366 return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R2; 367 } 368 369 /* 370 * Function to read channel values 371 * @madc - pointer to twl4030_madc_data struct 372 * @reg_base - Base address of the first channel 373 * @Channels - 16 bit bitmap. If the bit is set, channel's value is read 374 * @buf - The channel values are stored here. if read fails error 375 * @raw - Return raw values without conversion 376 * value is stored 377 * Returns the number of successfully read channels. 378 */ 379 static int twl4030_madc_read_channels(struct twl4030_madc_data *madc, 380 u8 reg_base, unsigned 381 long channels, int *buf, 382 bool raw) 383 { 384 int count = 0; 385 int i; 386 u8 reg; 387 388 for_each_set_bit(i, &channels, TWL4030_MADC_MAX_CHANNELS) { 389 reg = reg_base + (2 * i); 390 buf[i] = twl4030_madc_channel_raw_read(madc, reg); 391 if (buf[i] < 0) { 392 dev_err(madc->dev, "Unable to read register 0x%X\n", 393 reg); 394 return buf[i]; 395 } 396 if (raw) { 397 count++; 398 continue; 399 } 400 switch (i) { 401 case 10: 402 buf[i] = twl4030battery_current(buf[i]); 403 if (buf[i] < 0) { 404 dev_err(madc->dev, "err reading current\n"); 405 return buf[i]; 406 } else { 407 count++; 408 buf[i] = buf[i] - 750; 409 } 410 break; 411 case 1: 412 buf[i] = twl4030battery_temperature(buf[i]); 413 if (buf[i] < 0) { 414 dev_err(madc->dev, "err reading temperature\n"); 415 return buf[i]; 416 } else { 417 buf[i] -= 3; 418 count++; 419 } 420 break; 421 default: 422 count++; 423 /* Analog Input (V) = conv_result * step_size / R 424 * conv_result = decimal value of 10-bit conversion 425 * result 426 * step size = 1.5 / (2 ^ 10 -1) 427 * R = Prescaler ratio for input channels. 428 * Result given in mV hence multiplied by 1000. 429 */ 430 buf[i] = (buf[i] * 3 * 1000 * 431 twl4030_divider_ratios[i].denominator) 432 / (2 * 1023 * 433 twl4030_divider_ratios[i].numerator); 434 } 435 } 436 437 return count; 438 } 439 440 /* 441 * Disables irq. 442 * @madc - pointer to twl4030_madc_data struct 443 * @id - irq number to be disabled 444 * can take one of TWL4030_MADC_RT, TWL4030_MADC_SW1, TWL4030_MADC_SW2 445 * corresponding to RT, SW1, SW2 conversion requests. 446 * Returns error if i2c read/write fails. 447 */ 448 static int twl4030_madc_disable_irq(struct twl4030_madc_data *madc, u8 id) 449 { 450 u8 val; 451 int ret; 452 453 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &val, madc->imr); 454 if (ret) { 455 dev_err(madc->dev, "unable to read imr register 0x%X\n", 456 madc->imr); 457 return ret; 458 } 459 val |= (1 << id); 460 ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, val, madc->imr); 461 if (ret) { 462 dev_err(madc->dev, 463 "unable to write imr register 0x%X\n", madc->imr); 464 return ret; 465 } 466 467 return 0; 468 } 469 470 static irqreturn_t twl4030_madc_threaded_irq_handler(int irq, void *_madc) 471 { 472 struct twl4030_madc_data *madc = _madc; 473 const struct twl4030_madc_conversion_method *method; 474 u8 isr_val, imr_val; 475 int i, len, ret; 476 struct twl4030_madc_request *r; 477 478 mutex_lock(&madc->lock); 479 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &isr_val, madc->isr); 480 if (ret) { 481 dev_err(madc->dev, "unable to read isr register 0x%X\n", 482 madc->isr); 483 goto err_i2c; 484 } 485 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &imr_val, madc->imr); 486 if (ret) { 487 dev_err(madc->dev, "unable to read imr register 0x%X\n", 488 madc->imr); 489 goto err_i2c; 490 } 491 isr_val &= ~imr_val; 492 for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) { 493 if (!(isr_val & (1 << i))) 494 continue; 495 ret = twl4030_madc_disable_irq(madc, i); 496 if (ret < 0) 497 dev_dbg(madc->dev, "Disable interrupt failed %d\n", i); 498 madc->requests[i].result_pending = true; 499 } 500 for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) { 501 r = &madc->requests[i]; 502 /* No pending results for this method, move to next one */ 503 if (!r->result_pending) 504 continue; 505 method = &twl4030_conversion_methods[r->method]; 506 /* Read results */ 507 len = twl4030_madc_read_channels(madc, method->rbase, 508 r->channels, r->rbuf, r->raw); 509 /* Free request */ 510 r->result_pending = false; 511 r->active = false; 512 } 513 mutex_unlock(&madc->lock); 514 515 return IRQ_HANDLED; 516 517 err_i2c: 518 /* 519 * In case of error check whichever request is active 520 * and service the same. 521 */ 522 for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) { 523 r = &madc->requests[i]; 524 if (!r->active) 525 continue; 526 method = &twl4030_conversion_methods[r->method]; 527 /* Read results */ 528 len = twl4030_madc_read_channels(madc, method->rbase, 529 r->channels, r->rbuf, r->raw); 530 /* Free request */ 531 r->result_pending = false; 532 r->active = false; 533 } 534 mutex_unlock(&madc->lock); 535 536 return IRQ_HANDLED; 537 } 538 539 /* 540 * Function which enables the madc conversion 541 * by writing to the control register. 542 * @madc - pointer to twl4030_madc_data struct 543 * @conv_method - can be TWL4030_MADC_RT, TWL4030_MADC_SW2, TWL4030_MADC_SW1 544 * corresponding to RT SW1 or SW2 conversion methods. 545 * Returns 0 if succeeds else a negative error value 546 */ 547 static int twl4030_madc_start_conversion(struct twl4030_madc_data *madc, 548 int conv_method) 549 { 550 const struct twl4030_madc_conversion_method *method; 551 int ret = 0; 552 553 if (conv_method != TWL4030_MADC_SW1 && conv_method != TWL4030_MADC_SW2) 554 return -ENOTSUPP; 555 556 method = &twl4030_conversion_methods[conv_method]; 557 ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, TWL4030_MADC_SW_START, 558 method->ctrl); 559 if (ret) { 560 dev_err(madc->dev, "unable to write ctrl register 0x%X\n", 561 method->ctrl); 562 return ret; 563 } 564 565 return 0; 566 } 567 568 /* 569 * Function that waits for conversion to be ready 570 * @madc - pointer to twl4030_madc_data struct 571 * @timeout_ms - timeout value in milliseconds 572 * @status_reg - ctrl register 573 * returns 0 if succeeds else a negative error value 574 */ 575 static int twl4030_madc_wait_conversion_ready(struct twl4030_madc_data *madc, 576 unsigned int timeout_ms, 577 u8 status_reg) 578 { 579 unsigned long timeout; 580 int ret; 581 582 timeout = jiffies + msecs_to_jiffies(timeout_ms); 583 do { 584 u8 reg; 585 586 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, ®, status_reg); 587 if (ret) { 588 dev_err(madc->dev, 589 "unable to read status register 0x%X\n", 590 status_reg); 591 return ret; 592 } 593 if (!(reg & TWL4030_MADC_BUSY) && (reg & TWL4030_MADC_EOC_SW)) 594 return 0; 595 usleep_range(500, 2000); 596 } while (!time_after(jiffies, timeout)); 597 dev_err(madc->dev, "conversion timeout!\n"); 598 599 return -EAGAIN; 600 } 601 602 /* 603 * An exported function which can be called from other kernel drivers. 604 * @req twl4030_madc_request structure 605 * req->rbuf will be filled with read values of channels based on the 606 * channel index. If a particular channel reading fails there will 607 * be a negative error value in the corresponding array element. 608 * returns 0 if succeeds else error value 609 */ 610 static int twl4030_madc_conversion(struct twl4030_madc_request *req) 611 { 612 const struct twl4030_madc_conversion_method *method; 613 int ret; 614 615 if (!req || !twl4030_madc) 616 return -EINVAL; 617 618 mutex_lock(&twl4030_madc->lock); 619 if (req->method < TWL4030_MADC_RT || req->method > TWL4030_MADC_SW2) { 620 ret = -EINVAL; 621 goto out; 622 } 623 /* Do we have a conversion request ongoing */ 624 if (twl4030_madc->requests[req->method].active) { 625 ret = -EBUSY; 626 goto out; 627 } 628 method = &twl4030_conversion_methods[req->method]; 629 /* Select channels to be converted */ 630 ret = twl_i2c_write_u16(TWL4030_MODULE_MADC, req->channels, method->sel); 631 if (ret) { 632 dev_err(twl4030_madc->dev, 633 "unable to write sel register 0x%X\n", method->sel); 634 goto out; 635 } 636 /* Select averaging for all channels if do_avg is set */ 637 if (req->do_avg) { 638 ret = twl_i2c_write_u16(TWL4030_MODULE_MADC, req->channels, 639 method->avg); 640 if (ret) { 641 dev_err(twl4030_madc->dev, 642 "unable to write avg register 0x%X\n", 643 method->avg); 644 goto out; 645 } 646 } 647 /* With RT method we should not be here anymore */ 648 if (req->method == TWL4030_MADC_RT) { 649 ret = -EINVAL; 650 goto out; 651 } 652 ret = twl4030_madc_start_conversion(twl4030_madc, req->method); 653 if (ret < 0) 654 goto out; 655 twl4030_madc->requests[req->method].active = true; 656 /* Wait until conversion is ready (ctrl register returns EOC) */ 657 ret = twl4030_madc_wait_conversion_ready(twl4030_madc, 5, method->ctrl); 658 if (ret) { 659 twl4030_madc->requests[req->method].active = false; 660 goto out; 661 } 662 ret = twl4030_madc_read_channels(twl4030_madc, method->rbase, 663 req->channels, req->rbuf, req->raw); 664 twl4030_madc->requests[req->method].active = false; 665 666 out: 667 mutex_unlock(&twl4030_madc->lock); 668 669 return ret; 670 } 671 672 /** 673 * twl4030_madc_set_current_generator() - setup bias current 674 * 675 * @madc: pointer to twl4030_madc_data struct 676 * @chan: can be one of the two values: 677 * 0 - Enables bias current for main battery type reading 678 * 1 - Enables bias current for main battery temperature sensing 679 * @on: enable or disable chan. 680 * 681 * Function to enable or disable bias current for 682 * main battery type reading or temperature sensing 683 */ 684 static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc, 685 int chan, int on) 686 { 687 int ret; 688 int regmask; 689 u8 regval; 690 691 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, 692 ®val, TWL4030_BCI_BCICTL1); 693 if (ret) { 694 dev_err(madc->dev, "unable to read BCICTL1 reg 0x%X", 695 TWL4030_BCI_BCICTL1); 696 return ret; 697 } 698 699 regmask = chan ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN; 700 if (on) 701 regval |= regmask; 702 else 703 regval &= ~regmask; 704 705 ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 706 regval, TWL4030_BCI_BCICTL1); 707 if (ret) { 708 dev_err(madc->dev, "unable to write BCICTL1 reg 0x%X\n", 709 TWL4030_BCI_BCICTL1); 710 return ret; 711 } 712 713 return 0; 714 } 715 716 /* 717 * Function that sets MADC software power on bit to enable MADC 718 * @madc - pointer to twl4030_madc_data struct 719 * @on - Enable or disable MADC software power on bit. 720 * returns error if i2c read/write fails else 0 721 */ 722 static int twl4030_madc_set_power(struct twl4030_madc_data *madc, int on) 723 { 724 u8 regval; 725 int ret; 726 727 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, 728 ®val, TWL4030_MADC_CTRL1); 729 if (ret) { 730 dev_err(madc->dev, "unable to read madc ctrl1 reg 0x%X\n", 731 TWL4030_MADC_CTRL1); 732 return ret; 733 } 734 if (on) 735 regval |= TWL4030_MADC_MADCON; 736 else 737 regval &= ~TWL4030_MADC_MADCON; 738 ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, regval, TWL4030_MADC_CTRL1); 739 if (ret) { 740 dev_err(madc->dev, "unable to write madc ctrl1 reg 0x%X\n", 741 TWL4030_MADC_CTRL1); 742 return ret; 743 } 744 745 return 0; 746 } 747 748 /* 749 * Initialize MADC and request for threaded irq 750 */ 751 static int twl4030_madc_probe(struct platform_device *pdev) 752 { 753 struct twl4030_madc_data *madc; 754 struct twl4030_madc_platform_data *pdata = dev_get_platdata(&pdev->dev); 755 struct device_node *np = pdev->dev.of_node; 756 int irq, ret; 757 u8 regval; 758 struct iio_dev *iio_dev = NULL; 759 760 if (!pdata && !np) { 761 dev_err(&pdev->dev, "neither platform data nor Device Tree node available\n"); 762 return -EINVAL; 763 } 764 765 iio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*madc)); 766 if (!iio_dev) { 767 dev_err(&pdev->dev, "failed allocating iio device\n"); 768 return -ENOMEM; 769 } 770 771 madc = iio_priv(iio_dev); 772 madc->dev = &pdev->dev; 773 774 iio_dev->name = dev_name(&pdev->dev); 775 iio_dev->dev.parent = &pdev->dev; 776 iio_dev->dev.of_node = pdev->dev.of_node; 777 iio_dev->info = &twl4030_madc_iio_info; 778 iio_dev->modes = INDIO_DIRECT_MODE; 779 iio_dev->channels = twl4030_madc_iio_channels; 780 iio_dev->num_channels = ARRAY_SIZE(twl4030_madc_iio_channels); 781 782 /* 783 * Phoenix provides 2 interrupt lines. The first one is connected to 784 * the OMAP. The other one can be connected to the other processor such 785 * as modem. Hence two separate ISR and IMR registers. 786 */ 787 if (pdata) 788 madc->use_second_irq = (pdata->irq_line != 1); 789 else 790 madc->use_second_irq = of_property_read_bool(np, 791 "ti,system-uses-second-madc-irq"); 792 793 madc->imr = madc->use_second_irq ? TWL4030_MADC_IMR2 : 794 TWL4030_MADC_IMR1; 795 madc->isr = madc->use_second_irq ? TWL4030_MADC_ISR2 : 796 TWL4030_MADC_ISR1; 797 798 ret = twl4030_madc_set_power(madc, 1); 799 if (ret < 0) 800 return ret; 801 ret = twl4030_madc_set_current_generator(madc, 0, 1); 802 if (ret < 0) 803 goto err_current_generator; 804 805 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, 806 ®val, TWL4030_BCI_BCICTL1); 807 if (ret) { 808 dev_err(&pdev->dev, "unable to read reg BCI CTL1 0x%X\n", 809 TWL4030_BCI_BCICTL1); 810 goto err_i2c; 811 } 812 regval |= TWL4030_BCI_MESBAT; 813 ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 814 regval, TWL4030_BCI_BCICTL1); 815 if (ret) { 816 dev_err(&pdev->dev, "unable to write reg BCI Ctl1 0x%X\n", 817 TWL4030_BCI_BCICTL1); 818 goto err_i2c; 819 } 820 821 /* Check that MADC clock is on */ 822 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, ®val, TWL4030_REG_GPBR1); 823 if (ret) { 824 dev_err(&pdev->dev, "unable to read reg GPBR1 0x%X\n", 825 TWL4030_REG_GPBR1); 826 goto err_i2c; 827 } 828 829 /* If MADC clk is not on, turn it on */ 830 if (!(regval & TWL4030_GPBR1_MADC_HFCLK_EN)) { 831 dev_info(&pdev->dev, "clk disabled, enabling\n"); 832 regval |= TWL4030_GPBR1_MADC_HFCLK_EN; 833 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, regval, 834 TWL4030_REG_GPBR1); 835 if (ret) { 836 dev_err(&pdev->dev, "unable to write reg GPBR1 0x%X\n", 837 TWL4030_REG_GPBR1); 838 goto err_i2c; 839 } 840 } 841 842 platform_set_drvdata(pdev, iio_dev); 843 mutex_init(&madc->lock); 844 845 irq = platform_get_irq(pdev, 0); 846 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, 847 twl4030_madc_threaded_irq_handler, 848 IRQF_TRIGGER_RISING | IRQF_ONESHOT, 849 "twl4030_madc", madc); 850 if (ret) { 851 dev_err(&pdev->dev, "could not request irq\n"); 852 goto err_i2c; 853 } 854 twl4030_madc = madc; 855 856 /* Configure MADC[3:6] */ 857 ret = twl_i2c_read_u8(TWL_MODULE_USB, ®val, 858 TWL4030_USB_CARKIT_ANA_CTRL); 859 if (ret) { 860 dev_err(&pdev->dev, "unable to read reg CARKIT_ANA_CTRL 0x%X\n", 861 TWL4030_USB_CARKIT_ANA_CTRL); 862 goto err_i2c; 863 } 864 regval |= TWL4030_USB_SEL_MADC_MCPC; 865 ret = twl_i2c_write_u8(TWL_MODULE_USB, regval, 866 TWL4030_USB_CARKIT_ANA_CTRL); 867 if (ret) { 868 dev_err(&pdev->dev, "unable to write reg CARKIT_ANA_CTRL 0x%X\n", 869 TWL4030_USB_CARKIT_ANA_CTRL); 870 goto err_i2c; 871 } 872 873 /* Enable 3v1 bias regulator for MADC[3:6] */ 874 madc->usb3v1 = devm_regulator_get(madc->dev, "vusb3v1"); 875 if (IS_ERR(madc->usb3v1)) { 876 ret = -ENODEV; 877 goto err_i2c; 878 } 879 880 ret = regulator_enable(madc->usb3v1); 881 if (ret) { 882 dev_err(madc->dev, "could not enable 3v1 bias regulator\n"); 883 goto err_i2c; 884 } 885 886 ret = iio_device_register(iio_dev); 887 if (ret) { 888 dev_err(&pdev->dev, "could not register iio device\n"); 889 goto err_usb3v1; 890 } 891 892 return 0; 893 894 err_usb3v1: 895 regulator_disable(madc->usb3v1); 896 err_i2c: 897 twl4030_madc_set_current_generator(madc, 0, 0); 898 err_current_generator: 899 twl4030_madc_set_power(madc, 0); 900 return ret; 901 } 902 903 static int twl4030_madc_remove(struct platform_device *pdev) 904 { 905 struct iio_dev *iio_dev = platform_get_drvdata(pdev); 906 struct twl4030_madc_data *madc = iio_priv(iio_dev); 907 908 iio_device_unregister(iio_dev); 909 910 twl4030_madc_set_current_generator(madc, 0, 0); 911 twl4030_madc_set_power(madc, 0); 912 913 regulator_disable(madc->usb3v1); 914 915 return 0; 916 } 917 918 #ifdef CONFIG_OF 919 static const struct of_device_id twl_madc_of_match[] = { 920 { .compatible = "ti,twl4030-madc", }, 921 { }, 922 }; 923 MODULE_DEVICE_TABLE(of, twl_madc_of_match); 924 #endif 925 926 static struct platform_driver twl4030_madc_driver = { 927 .probe = twl4030_madc_probe, 928 .remove = twl4030_madc_remove, 929 .driver = { 930 .name = "twl4030_madc", 931 .of_match_table = of_match_ptr(twl_madc_of_match), 932 }, 933 }; 934 935 module_platform_driver(twl4030_madc_driver); 936 937 MODULE_DESCRIPTION("TWL4030 ADC driver"); 938 MODULE_LICENSE("GPL"); 939 MODULE_AUTHOR("J Keerthy"); 940 MODULE_ALIAS("platform:twl4030_madc"); 941