1 /* 2 * 3 * TWL4030 MADC module driver-This driver monitors the real time 4 * conversion of analog signals like battery temperature, 5 * battery type, battery level etc. 6 * 7 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/ 8 * J Keerthy <j-keerthy@ti.com> 9 * 10 * Based on twl4030-madc.c 11 * Copyright (C) 2008 Nokia Corporation 12 * Mikko Ylinen <mikko.k.ylinen@nokia.com> 13 * 14 * Amit Kucheria <amit.kucheria@canonical.com> 15 * 16 * This program is free software; you can redistribute it and/or 17 * modify it under the terms of the GNU General Public License 18 * version 2 as published by the Free Software Foundation. 19 * 20 * This program is distributed in the hope that it will be useful, but 21 * WITHOUT ANY WARRANTY; without even the implied warranty of 22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 23 * General Public License for more details. 24 * 25 * You should have received a copy of the GNU General Public License 26 * along with this program; if not, write to the Free Software 27 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 28 * 02110-1301 USA 29 * 30 */ 31 32 #include <linux/device.h> 33 #include <linux/interrupt.h> 34 #include <linux/kernel.h> 35 #include <linux/delay.h> 36 #include <linux/platform_device.h> 37 #include <linux/slab.h> 38 #include <linux/mfd/twl.h> 39 #include <linux/module.h> 40 #include <linux/stddef.h> 41 #include <linux/mutex.h> 42 #include <linux/bitops.h> 43 #include <linux/jiffies.h> 44 #include <linux/types.h> 45 #include <linux/gfp.h> 46 #include <linux/err.h> 47 #include <linux/regulator/consumer.h> 48 49 #include <linux/iio/iio.h> 50 51 #define TWL4030_MADC_MAX_CHANNELS 16 52 53 #define TWL4030_MADC_CTRL1 0x00 54 #define TWL4030_MADC_CTRL2 0x01 55 56 #define TWL4030_MADC_RTSELECT_LSB 0x02 57 #define TWL4030_MADC_SW1SELECT_LSB 0x06 58 #define TWL4030_MADC_SW2SELECT_LSB 0x0A 59 60 #define TWL4030_MADC_RTAVERAGE_LSB 0x04 61 #define TWL4030_MADC_SW1AVERAGE_LSB 0x08 62 #define TWL4030_MADC_SW2AVERAGE_LSB 0x0C 63 64 #define TWL4030_MADC_CTRL_SW1 0x12 65 #define TWL4030_MADC_CTRL_SW2 0x13 66 67 #define TWL4030_MADC_RTCH0_LSB 0x17 68 #define TWL4030_MADC_GPCH0_LSB 0x37 69 70 #define TWL4030_MADC_MADCON (1 << 0) /* MADC power on */ 71 #define TWL4030_MADC_BUSY (1 << 0) /* MADC busy */ 72 /* MADC conversion completion */ 73 #define TWL4030_MADC_EOC_SW (1 << 1) 74 /* MADC SWx start conversion */ 75 #define TWL4030_MADC_SW_START (1 << 5) 76 #define TWL4030_MADC_ADCIN0 (1 << 0) 77 #define TWL4030_MADC_ADCIN1 (1 << 1) 78 #define TWL4030_MADC_ADCIN2 (1 << 2) 79 #define TWL4030_MADC_ADCIN3 (1 << 3) 80 #define TWL4030_MADC_ADCIN4 (1 << 4) 81 #define TWL4030_MADC_ADCIN5 (1 << 5) 82 #define TWL4030_MADC_ADCIN6 (1 << 6) 83 #define TWL4030_MADC_ADCIN7 (1 << 7) 84 #define TWL4030_MADC_ADCIN8 (1 << 8) 85 #define TWL4030_MADC_ADCIN9 (1 << 9) 86 #define TWL4030_MADC_ADCIN10 (1 << 10) 87 #define TWL4030_MADC_ADCIN11 (1 << 11) 88 #define TWL4030_MADC_ADCIN12 (1 << 12) 89 #define TWL4030_MADC_ADCIN13 (1 << 13) 90 #define TWL4030_MADC_ADCIN14 (1 << 14) 91 #define TWL4030_MADC_ADCIN15 (1 << 15) 92 93 /* Fixed channels */ 94 #define TWL4030_MADC_BTEMP TWL4030_MADC_ADCIN1 95 #define TWL4030_MADC_VBUS TWL4030_MADC_ADCIN8 96 #define TWL4030_MADC_VBKB TWL4030_MADC_ADCIN9 97 #define TWL4030_MADC_ICHG TWL4030_MADC_ADCIN10 98 #define TWL4030_MADC_VCHG TWL4030_MADC_ADCIN11 99 #define TWL4030_MADC_VBAT TWL4030_MADC_ADCIN12 100 101 /* Step size and prescaler ratio */ 102 #define TEMP_STEP_SIZE 147 103 #define TEMP_PSR_R 100 104 #define CURR_STEP_SIZE 147 105 #define CURR_PSR_R1 44 106 #define CURR_PSR_R2 88 107 108 #define TWL4030_BCI_BCICTL1 0x23 109 #define TWL4030_BCI_CGAIN 0x020 110 #define TWL4030_BCI_MESBAT (1 << 1) 111 #define TWL4030_BCI_TYPEN (1 << 4) 112 #define TWL4030_BCI_ITHEN (1 << 3) 113 114 #define REG_BCICTL2 0x024 115 #define TWL4030_BCI_ITHSENS 0x007 116 117 /* Register and bits for GPBR1 register */ 118 #define TWL4030_REG_GPBR1 0x0c 119 #define TWL4030_GPBR1_MADC_HFCLK_EN (1 << 7) 120 121 #define TWL4030_USB_SEL_MADC_MCPC (1<<3) 122 #define TWL4030_USB_CARKIT_ANA_CTRL 0xBB 123 124 struct twl4030_madc_conversion_method { 125 u8 sel; 126 u8 avg; 127 u8 rbase; 128 u8 ctrl; 129 }; 130 131 /** 132 * struct twl4030_madc_request - madc request packet for channel conversion 133 * @channels: 16 bit bitmap for individual channels 134 * @do_avg: sample the input channel for 4 consecutive cycles 135 * @method: RT, SW1, SW2 136 * @type: Polling or interrupt based method 137 * @active: Flag if request is active 138 * @result_pending: Flag from irq handler, that result is ready 139 * @raw: Return raw value, do not convert it 140 * @rbuf: Result buffer 141 */ 142 struct twl4030_madc_request { 143 unsigned long channels; 144 bool do_avg; 145 u16 method; 146 u16 type; 147 bool active; 148 bool result_pending; 149 bool raw; 150 int rbuf[TWL4030_MADC_MAX_CHANNELS]; 151 }; 152 153 enum conversion_methods { 154 TWL4030_MADC_RT, 155 TWL4030_MADC_SW1, 156 TWL4030_MADC_SW2, 157 TWL4030_MADC_NUM_METHODS 158 }; 159 160 enum sample_type { 161 TWL4030_MADC_WAIT, 162 TWL4030_MADC_IRQ_ONESHOT, 163 TWL4030_MADC_IRQ_REARM 164 }; 165 166 /** 167 * struct twl4030_madc_data - a container for madc info 168 * @dev: Pointer to device structure for madc 169 * @lock: Mutex protecting this data structure 170 * @regulator: Pointer to bias regulator for madc 171 * @requests: Array of request struct corresponding to SW1, SW2 and RT 172 * @use_second_irq: IRQ selection (main or co-processor) 173 * @imr: Interrupt mask register of MADC 174 * @isr: Interrupt status register of MADC 175 */ 176 struct twl4030_madc_data { 177 struct device *dev; 178 struct mutex lock; /* mutex protecting this data structure */ 179 struct regulator *usb3v1; 180 struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS]; 181 bool use_second_irq; 182 u8 imr; 183 u8 isr; 184 }; 185 186 static int twl4030_madc_conversion(struct twl4030_madc_request *req); 187 188 static int twl4030_madc_read(struct iio_dev *iio_dev, 189 const struct iio_chan_spec *chan, 190 int *val, int *val2, long mask) 191 { 192 struct twl4030_madc_data *madc = iio_priv(iio_dev); 193 struct twl4030_madc_request req; 194 int ret; 195 196 req.method = madc->use_second_irq ? TWL4030_MADC_SW2 : TWL4030_MADC_SW1; 197 198 req.channels = BIT(chan->channel); 199 req.active = false; 200 req.type = TWL4030_MADC_WAIT; 201 req.raw = !(mask == IIO_CHAN_INFO_PROCESSED); 202 req.do_avg = (mask == IIO_CHAN_INFO_AVERAGE_RAW); 203 204 ret = twl4030_madc_conversion(&req); 205 if (ret < 0) 206 return ret; 207 208 *val = req.rbuf[chan->channel]; 209 210 return IIO_VAL_INT; 211 } 212 213 static const struct iio_info twl4030_madc_iio_info = { 214 .read_raw = &twl4030_madc_read, 215 .driver_module = THIS_MODULE, 216 }; 217 218 #define TWL4030_ADC_CHANNEL(_channel, _type, _name) { \ 219 .type = _type, \ 220 .channel = _channel, \ 221 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 222 BIT(IIO_CHAN_INFO_AVERAGE_RAW) | \ 223 BIT(IIO_CHAN_INFO_PROCESSED), \ 224 .datasheet_name = _name, \ 225 .indexed = 1, \ 226 } 227 228 static const struct iio_chan_spec twl4030_madc_iio_channels[] = { 229 TWL4030_ADC_CHANNEL(0, IIO_VOLTAGE, "ADCIN0"), 230 TWL4030_ADC_CHANNEL(1, IIO_TEMP, "ADCIN1"), 231 TWL4030_ADC_CHANNEL(2, IIO_VOLTAGE, "ADCIN2"), 232 TWL4030_ADC_CHANNEL(3, IIO_VOLTAGE, "ADCIN3"), 233 TWL4030_ADC_CHANNEL(4, IIO_VOLTAGE, "ADCIN4"), 234 TWL4030_ADC_CHANNEL(5, IIO_VOLTAGE, "ADCIN5"), 235 TWL4030_ADC_CHANNEL(6, IIO_VOLTAGE, "ADCIN6"), 236 TWL4030_ADC_CHANNEL(7, IIO_VOLTAGE, "ADCIN7"), 237 TWL4030_ADC_CHANNEL(8, IIO_VOLTAGE, "ADCIN8"), 238 TWL4030_ADC_CHANNEL(9, IIO_VOLTAGE, "ADCIN9"), 239 TWL4030_ADC_CHANNEL(10, IIO_CURRENT, "ADCIN10"), 240 TWL4030_ADC_CHANNEL(11, IIO_VOLTAGE, "ADCIN11"), 241 TWL4030_ADC_CHANNEL(12, IIO_VOLTAGE, "ADCIN12"), 242 TWL4030_ADC_CHANNEL(13, IIO_VOLTAGE, "ADCIN13"), 243 TWL4030_ADC_CHANNEL(14, IIO_VOLTAGE, "ADCIN14"), 244 TWL4030_ADC_CHANNEL(15, IIO_VOLTAGE, "ADCIN15"), 245 }; 246 247 static struct twl4030_madc_data *twl4030_madc; 248 249 struct twl4030_prescale_divider_ratios { 250 s16 numerator; 251 s16 denominator; 252 }; 253 254 static const struct twl4030_prescale_divider_ratios 255 twl4030_divider_ratios[16] = { 256 {1, 1}, /* CHANNEL 0 No Prescaler */ 257 {1, 1}, /* CHANNEL 1 No Prescaler */ 258 {6, 10}, /* CHANNEL 2 */ 259 {6, 10}, /* CHANNEL 3 */ 260 {6, 10}, /* CHANNEL 4 */ 261 {6, 10}, /* CHANNEL 5 */ 262 {6, 10}, /* CHANNEL 6 */ 263 {6, 10}, /* CHANNEL 7 */ 264 {3, 14}, /* CHANNEL 8 */ 265 {1, 3}, /* CHANNEL 9 */ 266 {1, 1}, /* CHANNEL 10 No Prescaler */ 267 {15, 100}, /* CHANNEL 11 */ 268 {1, 4}, /* CHANNEL 12 */ 269 {1, 1}, /* CHANNEL 13 Reserved channels */ 270 {1, 1}, /* CHANNEL 14 Reseved channels */ 271 {5, 11}, /* CHANNEL 15 */ 272 }; 273 274 275 /* Conversion table from -3 to 55 degrees Celcius */ 276 static int twl4030_therm_tbl[] = { 277 30800, 29500, 28300, 27100, 278 26000, 24900, 23900, 22900, 22000, 21100, 20300, 19400, 18700, 279 17900, 17200, 16500, 15900, 15300, 14700, 14100, 13600, 13100, 280 12600, 12100, 11600, 11200, 10800, 10400, 10000, 9630, 9280, 281 8950, 8620, 8310, 8020, 7730, 7460, 7200, 6950, 6710, 282 6470, 6250, 6040, 5830, 5640, 5450, 5260, 5090, 4920, 283 4760, 4600, 4450, 4310, 4170, 4040, 3910, 3790, 3670, 284 3550 285 }; 286 287 /* 288 * Structure containing the registers 289 * of different conversion methods supported by MADC. 290 * Hardware or RT real time conversion request initiated by external host 291 * processor for RT Signal conversions. 292 * External host processors can also request for non RT conversions 293 * SW1 and SW2 software conversions also called asynchronous or GPC request. 294 */ 295 static 296 const struct twl4030_madc_conversion_method twl4030_conversion_methods[] = { 297 [TWL4030_MADC_RT] = { 298 .sel = TWL4030_MADC_RTSELECT_LSB, 299 .avg = TWL4030_MADC_RTAVERAGE_LSB, 300 .rbase = TWL4030_MADC_RTCH0_LSB, 301 }, 302 [TWL4030_MADC_SW1] = { 303 .sel = TWL4030_MADC_SW1SELECT_LSB, 304 .avg = TWL4030_MADC_SW1AVERAGE_LSB, 305 .rbase = TWL4030_MADC_GPCH0_LSB, 306 .ctrl = TWL4030_MADC_CTRL_SW1, 307 }, 308 [TWL4030_MADC_SW2] = { 309 .sel = TWL4030_MADC_SW2SELECT_LSB, 310 .avg = TWL4030_MADC_SW2AVERAGE_LSB, 311 .rbase = TWL4030_MADC_GPCH0_LSB, 312 .ctrl = TWL4030_MADC_CTRL_SW2, 313 }, 314 }; 315 316 /** 317 * twl4030_madc_channel_raw_read() - Function to read a particular channel value 318 * @madc: pointer to struct twl4030_madc_data 319 * @reg: lsb of ADC Channel 320 * 321 * Return: 0 on success, an error code otherwise. 322 */ 323 static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg) 324 { 325 u16 val; 326 int ret; 327 /* 328 * For each ADC channel, we have MSB and LSB register pair. MSB address 329 * is always LSB address+1. reg parameter is the address of LSB register 330 */ 331 ret = twl_i2c_read_u16(TWL4030_MODULE_MADC, &val, reg); 332 if (ret) { 333 dev_err(madc->dev, "unable to read register 0x%X\n", reg); 334 return ret; 335 } 336 337 return (int)(val >> 6); 338 } 339 340 /* 341 * Return battery temperature in degrees Celsius 342 * Or < 0 on failure. 343 */ 344 static int twl4030battery_temperature(int raw_volt) 345 { 346 u8 val; 347 int temp, curr, volt, res, ret; 348 349 volt = (raw_volt * TEMP_STEP_SIZE) / TEMP_PSR_R; 350 /* Getting and calculating the supply current in micro amperes */ 351 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, &val, 352 REG_BCICTL2); 353 if (ret < 0) 354 return ret; 355 356 curr = ((val & TWL4030_BCI_ITHSENS) + 1) * 10; 357 /* Getting and calculating the thermistor resistance in ohms */ 358 res = volt * 1000 / curr; 359 /* calculating temperature */ 360 for (temp = 58; temp >= 0; temp--) { 361 int actual = twl4030_therm_tbl[temp]; 362 if ((actual - res) >= 0) 363 break; 364 } 365 366 return temp + 1; 367 } 368 369 static int twl4030battery_current(int raw_volt) 370 { 371 int ret; 372 u8 val; 373 374 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, &val, 375 TWL4030_BCI_BCICTL1); 376 if (ret) 377 return ret; 378 if (val & TWL4030_BCI_CGAIN) /* slope of 0.44 mV/mA */ 379 return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R1; 380 else /* slope of 0.88 mV/mA */ 381 return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R2; 382 } 383 384 /* 385 * Function to read channel values 386 * @madc - pointer to twl4030_madc_data struct 387 * @reg_base - Base address of the first channel 388 * @Channels - 16 bit bitmap. If the bit is set, channel's value is read 389 * @buf - The channel values are stored here. if read fails error 390 * @raw - Return raw values without conversion 391 * value is stored 392 * Returns the number of successfully read channels. 393 */ 394 static int twl4030_madc_read_channels(struct twl4030_madc_data *madc, 395 u8 reg_base, unsigned 396 long channels, int *buf, 397 bool raw) 398 { 399 int count = 0; 400 int i; 401 u8 reg; 402 403 for_each_set_bit(i, &channels, TWL4030_MADC_MAX_CHANNELS) { 404 reg = reg_base + (2 * i); 405 buf[i] = twl4030_madc_channel_raw_read(madc, reg); 406 if (buf[i] < 0) { 407 dev_err(madc->dev, "Unable to read register 0x%X\n", 408 reg); 409 return buf[i]; 410 } 411 if (raw) { 412 count++; 413 continue; 414 } 415 switch (i) { 416 case 10: 417 buf[i] = twl4030battery_current(buf[i]); 418 if (buf[i] < 0) { 419 dev_err(madc->dev, "err reading current\n"); 420 return buf[i]; 421 } else { 422 count++; 423 buf[i] = buf[i] - 750; 424 } 425 break; 426 case 1: 427 buf[i] = twl4030battery_temperature(buf[i]); 428 if (buf[i] < 0) { 429 dev_err(madc->dev, "err reading temperature\n"); 430 return buf[i]; 431 } else { 432 buf[i] -= 3; 433 count++; 434 } 435 break; 436 default: 437 count++; 438 /* Analog Input (V) = conv_result * step_size / R 439 * conv_result = decimal value of 10-bit conversion 440 * result 441 * step size = 1.5 / (2 ^ 10 -1) 442 * R = Prescaler ratio for input channels. 443 * Result given in mV hence multiplied by 1000. 444 */ 445 buf[i] = (buf[i] * 3 * 1000 * 446 twl4030_divider_ratios[i].denominator) 447 / (2 * 1023 * 448 twl4030_divider_ratios[i].numerator); 449 } 450 } 451 452 return count; 453 } 454 455 /* 456 * Disables irq. 457 * @madc - pointer to twl4030_madc_data struct 458 * @id - irq number to be disabled 459 * can take one of TWL4030_MADC_RT, TWL4030_MADC_SW1, TWL4030_MADC_SW2 460 * corresponding to RT, SW1, SW2 conversion requests. 461 * Returns error if i2c read/write fails. 462 */ 463 static int twl4030_madc_disable_irq(struct twl4030_madc_data *madc, u8 id) 464 { 465 u8 val; 466 int ret; 467 468 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &val, madc->imr); 469 if (ret) { 470 dev_err(madc->dev, "unable to read imr register 0x%X\n", 471 madc->imr); 472 return ret; 473 } 474 val |= (1 << id); 475 ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, val, madc->imr); 476 if (ret) { 477 dev_err(madc->dev, 478 "unable to write imr register 0x%X\n", madc->imr); 479 return ret; 480 } 481 482 return 0; 483 } 484 485 static irqreturn_t twl4030_madc_threaded_irq_handler(int irq, void *_madc) 486 { 487 struct twl4030_madc_data *madc = _madc; 488 const struct twl4030_madc_conversion_method *method; 489 u8 isr_val, imr_val; 490 int i, len, ret; 491 struct twl4030_madc_request *r; 492 493 mutex_lock(&madc->lock); 494 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &isr_val, madc->isr); 495 if (ret) { 496 dev_err(madc->dev, "unable to read isr register 0x%X\n", 497 madc->isr); 498 goto err_i2c; 499 } 500 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &imr_val, madc->imr); 501 if (ret) { 502 dev_err(madc->dev, "unable to read imr register 0x%X\n", 503 madc->imr); 504 goto err_i2c; 505 } 506 isr_val &= ~imr_val; 507 for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) { 508 if (!(isr_val & (1 << i))) 509 continue; 510 ret = twl4030_madc_disable_irq(madc, i); 511 if (ret < 0) 512 dev_dbg(madc->dev, "Disable interrupt failed %d\n", i); 513 madc->requests[i].result_pending = 1; 514 } 515 for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) { 516 r = &madc->requests[i]; 517 /* No pending results for this method, move to next one */ 518 if (!r->result_pending) 519 continue; 520 method = &twl4030_conversion_methods[r->method]; 521 /* Read results */ 522 len = twl4030_madc_read_channels(madc, method->rbase, 523 r->channels, r->rbuf, r->raw); 524 /* Free request */ 525 r->result_pending = 0; 526 r->active = 0; 527 } 528 mutex_unlock(&madc->lock); 529 530 return IRQ_HANDLED; 531 532 err_i2c: 533 /* 534 * In case of error check whichever request is active 535 * and service the same. 536 */ 537 for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) { 538 r = &madc->requests[i]; 539 if (r->active == 0) 540 continue; 541 method = &twl4030_conversion_methods[r->method]; 542 /* Read results */ 543 len = twl4030_madc_read_channels(madc, method->rbase, 544 r->channels, r->rbuf, r->raw); 545 /* Free request */ 546 r->result_pending = 0; 547 r->active = 0; 548 } 549 mutex_unlock(&madc->lock); 550 551 return IRQ_HANDLED; 552 } 553 554 /* 555 * Function which enables the madc conversion 556 * by writing to the control register. 557 * @madc - pointer to twl4030_madc_data struct 558 * @conv_method - can be TWL4030_MADC_RT, TWL4030_MADC_SW2, TWL4030_MADC_SW1 559 * corresponding to RT SW1 or SW2 conversion methods. 560 * Returns 0 if succeeds else a negative error value 561 */ 562 static int twl4030_madc_start_conversion(struct twl4030_madc_data *madc, 563 int conv_method) 564 { 565 const struct twl4030_madc_conversion_method *method; 566 int ret = 0; 567 568 if (conv_method != TWL4030_MADC_SW1 && conv_method != TWL4030_MADC_SW2) 569 return -ENOTSUPP; 570 571 method = &twl4030_conversion_methods[conv_method]; 572 ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, TWL4030_MADC_SW_START, 573 method->ctrl); 574 if (ret) { 575 dev_err(madc->dev, "unable to write ctrl register 0x%X\n", 576 method->ctrl); 577 return ret; 578 } 579 580 return 0; 581 } 582 583 /* 584 * Function that waits for conversion to be ready 585 * @madc - pointer to twl4030_madc_data struct 586 * @timeout_ms - timeout value in milliseconds 587 * @status_reg - ctrl register 588 * returns 0 if succeeds else a negative error value 589 */ 590 static int twl4030_madc_wait_conversion_ready(struct twl4030_madc_data *madc, 591 unsigned int timeout_ms, 592 u8 status_reg) 593 { 594 unsigned long timeout; 595 int ret; 596 597 timeout = jiffies + msecs_to_jiffies(timeout_ms); 598 do { 599 u8 reg; 600 601 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, ®, status_reg); 602 if (ret) { 603 dev_err(madc->dev, 604 "unable to read status register 0x%X\n", 605 status_reg); 606 return ret; 607 } 608 if (!(reg & TWL4030_MADC_BUSY) && (reg & TWL4030_MADC_EOC_SW)) 609 return 0; 610 usleep_range(500, 2000); 611 } while (!time_after(jiffies, timeout)); 612 dev_err(madc->dev, "conversion timeout!\n"); 613 614 return -EAGAIN; 615 } 616 617 /* 618 * An exported function which can be called from other kernel drivers. 619 * @req twl4030_madc_request structure 620 * req->rbuf will be filled with read values of channels based on the 621 * channel index. If a particular channel reading fails there will 622 * be a negative error value in the corresponding array element. 623 * returns 0 if succeeds else error value 624 */ 625 static int twl4030_madc_conversion(struct twl4030_madc_request *req) 626 { 627 const struct twl4030_madc_conversion_method *method; 628 int ret; 629 630 if (!req || !twl4030_madc) 631 return -EINVAL; 632 633 mutex_lock(&twl4030_madc->lock); 634 if (req->method < TWL4030_MADC_RT || req->method > TWL4030_MADC_SW2) { 635 ret = -EINVAL; 636 goto out; 637 } 638 /* Do we have a conversion request ongoing */ 639 if (twl4030_madc->requests[req->method].active) { 640 ret = -EBUSY; 641 goto out; 642 } 643 method = &twl4030_conversion_methods[req->method]; 644 /* Select channels to be converted */ 645 ret = twl_i2c_write_u16(TWL4030_MODULE_MADC, req->channels, method->sel); 646 if (ret) { 647 dev_err(twl4030_madc->dev, 648 "unable to write sel register 0x%X\n", method->sel); 649 goto out; 650 } 651 /* Select averaging for all channels if do_avg is set */ 652 if (req->do_avg) { 653 ret = twl_i2c_write_u16(TWL4030_MODULE_MADC, req->channels, 654 method->avg); 655 if (ret) { 656 dev_err(twl4030_madc->dev, 657 "unable to write avg register 0x%X\n", 658 method->avg); 659 goto out; 660 } 661 } 662 /* With RT method we should not be here anymore */ 663 if (req->method == TWL4030_MADC_RT) { 664 ret = -EINVAL; 665 goto out; 666 } 667 ret = twl4030_madc_start_conversion(twl4030_madc, req->method); 668 if (ret < 0) 669 goto out; 670 twl4030_madc->requests[req->method].active = 1; 671 /* Wait until conversion is ready (ctrl register returns EOC) */ 672 ret = twl4030_madc_wait_conversion_ready(twl4030_madc, 5, method->ctrl); 673 if (ret) { 674 twl4030_madc->requests[req->method].active = 0; 675 goto out; 676 } 677 ret = twl4030_madc_read_channels(twl4030_madc, method->rbase, 678 req->channels, req->rbuf, req->raw); 679 twl4030_madc->requests[req->method].active = 0; 680 681 out: 682 mutex_unlock(&twl4030_madc->lock); 683 684 return ret; 685 } 686 687 /** 688 * twl4030_madc_set_current_generator() - setup bias current 689 * 690 * @madc: pointer to twl4030_madc_data struct 691 * @chan: can be one of the two values: 692 * 0 - Enables bias current for main battery type reading 693 * 1 - Enables bias current for main battery temperature sensing 694 * @on: enable or disable chan. 695 * 696 * Function to enable or disable bias current for 697 * main battery type reading or temperature sensing 698 */ 699 static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc, 700 int chan, int on) 701 { 702 int ret; 703 int regmask; 704 u8 regval; 705 706 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, 707 ®val, TWL4030_BCI_BCICTL1); 708 if (ret) { 709 dev_err(madc->dev, "unable to read BCICTL1 reg 0x%X", 710 TWL4030_BCI_BCICTL1); 711 return ret; 712 } 713 714 regmask = chan ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN; 715 if (on) 716 regval |= regmask; 717 else 718 regval &= ~regmask; 719 720 ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 721 regval, TWL4030_BCI_BCICTL1); 722 if (ret) { 723 dev_err(madc->dev, "unable to write BCICTL1 reg 0x%X\n", 724 TWL4030_BCI_BCICTL1); 725 return ret; 726 } 727 728 return 0; 729 } 730 731 /* 732 * Function that sets MADC software power on bit to enable MADC 733 * @madc - pointer to twl4030_madc_data struct 734 * @on - Enable or disable MADC software power on bit. 735 * returns error if i2c read/write fails else 0 736 */ 737 static int twl4030_madc_set_power(struct twl4030_madc_data *madc, int on) 738 { 739 u8 regval; 740 int ret; 741 742 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, 743 ®val, TWL4030_MADC_CTRL1); 744 if (ret) { 745 dev_err(madc->dev, "unable to read madc ctrl1 reg 0x%X\n", 746 TWL4030_MADC_CTRL1); 747 return ret; 748 } 749 if (on) 750 regval |= TWL4030_MADC_MADCON; 751 else 752 regval &= ~TWL4030_MADC_MADCON; 753 ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, regval, TWL4030_MADC_CTRL1); 754 if (ret) { 755 dev_err(madc->dev, "unable to write madc ctrl1 reg 0x%X\n", 756 TWL4030_MADC_CTRL1); 757 return ret; 758 } 759 760 return 0; 761 } 762 763 /* 764 * Initialize MADC and request for threaded irq 765 */ 766 static int twl4030_madc_probe(struct platform_device *pdev) 767 { 768 struct twl4030_madc_data *madc; 769 struct twl4030_madc_platform_data *pdata = dev_get_platdata(&pdev->dev); 770 struct device_node *np = pdev->dev.of_node; 771 int irq, ret; 772 u8 regval; 773 struct iio_dev *iio_dev = NULL; 774 775 if (!pdata && !np) { 776 dev_err(&pdev->dev, "neither platform data nor Device Tree node available\n"); 777 return -EINVAL; 778 } 779 780 iio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*madc)); 781 if (!iio_dev) { 782 dev_err(&pdev->dev, "failed allocating iio device\n"); 783 return -ENOMEM; 784 } 785 786 madc = iio_priv(iio_dev); 787 madc->dev = &pdev->dev; 788 789 iio_dev->name = dev_name(&pdev->dev); 790 iio_dev->dev.parent = &pdev->dev; 791 iio_dev->dev.of_node = pdev->dev.of_node; 792 iio_dev->info = &twl4030_madc_iio_info; 793 iio_dev->modes = INDIO_DIRECT_MODE; 794 iio_dev->channels = twl4030_madc_iio_channels; 795 iio_dev->num_channels = ARRAY_SIZE(twl4030_madc_iio_channels); 796 797 /* 798 * Phoenix provides 2 interrupt lines. The first one is connected to 799 * the OMAP. The other one can be connected to the other processor such 800 * as modem. Hence two separate ISR and IMR registers. 801 */ 802 if (pdata) 803 madc->use_second_irq = (pdata->irq_line != 1); 804 else 805 madc->use_second_irq = of_property_read_bool(np, 806 "ti,system-uses-second-madc-irq"); 807 808 madc->imr = madc->use_second_irq ? TWL4030_MADC_IMR2 : 809 TWL4030_MADC_IMR1; 810 madc->isr = madc->use_second_irq ? TWL4030_MADC_ISR2 : 811 TWL4030_MADC_ISR1; 812 813 ret = twl4030_madc_set_power(madc, 1); 814 if (ret < 0) 815 return ret; 816 ret = twl4030_madc_set_current_generator(madc, 0, 1); 817 if (ret < 0) 818 goto err_current_generator; 819 820 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, 821 ®val, TWL4030_BCI_BCICTL1); 822 if (ret) { 823 dev_err(&pdev->dev, "unable to read reg BCI CTL1 0x%X\n", 824 TWL4030_BCI_BCICTL1); 825 goto err_i2c; 826 } 827 regval |= TWL4030_BCI_MESBAT; 828 ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 829 regval, TWL4030_BCI_BCICTL1); 830 if (ret) { 831 dev_err(&pdev->dev, "unable to write reg BCI Ctl1 0x%X\n", 832 TWL4030_BCI_BCICTL1); 833 goto err_i2c; 834 } 835 836 /* Check that MADC clock is on */ 837 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, ®val, TWL4030_REG_GPBR1); 838 if (ret) { 839 dev_err(&pdev->dev, "unable to read reg GPBR1 0x%X\n", 840 TWL4030_REG_GPBR1); 841 goto err_i2c; 842 } 843 844 /* If MADC clk is not on, turn it on */ 845 if (!(regval & TWL4030_GPBR1_MADC_HFCLK_EN)) { 846 dev_info(&pdev->dev, "clk disabled, enabling\n"); 847 regval |= TWL4030_GPBR1_MADC_HFCLK_EN; 848 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, regval, 849 TWL4030_REG_GPBR1); 850 if (ret) { 851 dev_err(&pdev->dev, "unable to write reg GPBR1 0x%X\n", 852 TWL4030_REG_GPBR1); 853 goto err_i2c; 854 } 855 } 856 857 platform_set_drvdata(pdev, iio_dev); 858 mutex_init(&madc->lock); 859 860 irq = platform_get_irq(pdev, 0); 861 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, 862 twl4030_madc_threaded_irq_handler, 863 IRQF_TRIGGER_RISING | IRQF_ONESHOT, 864 "twl4030_madc", madc); 865 if (ret) { 866 dev_err(&pdev->dev, "could not request irq\n"); 867 goto err_i2c; 868 } 869 twl4030_madc = madc; 870 871 /* Configure MADC[3:6] */ 872 ret = twl_i2c_read_u8(TWL_MODULE_USB, ®val, 873 TWL4030_USB_CARKIT_ANA_CTRL); 874 if (ret) { 875 dev_err(&pdev->dev, "unable to read reg CARKIT_ANA_CTRL 0x%X\n", 876 TWL4030_USB_CARKIT_ANA_CTRL); 877 goto err_i2c; 878 } 879 regval |= TWL4030_USB_SEL_MADC_MCPC; 880 ret = twl_i2c_write_u8(TWL_MODULE_USB, regval, 881 TWL4030_USB_CARKIT_ANA_CTRL); 882 if (ret) { 883 dev_err(&pdev->dev, "unable to write reg CARKIT_ANA_CTRL 0x%X\n", 884 TWL4030_USB_CARKIT_ANA_CTRL); 885 goto err_i2c; 886 } 887 888 /* Enable 3v1 bias regulator for MADC[3:6] */ 889 madc->usb3v1 = devm_regulator_get(madc->dev, "vusb3v1"); 890 if (IS_ERR(madc->usb3v1)) { 891 ret = -ENODEV; 892 goto err_i2c; 893 } 894 895 ret = regulator_enable(madc->usb3v1); 896 if (ret) { 897 dev_err(madc->dev, "could not enable 3v1 bias regulator\n"); 898 goto err_i2c; 899 } 900 901 ret = iio_device_register(iio_dev); 902 if (ret) { 903 dev_err(&pdev->dev, "could not register iio device\n"); 904 goto err_usb3v1; 905 } 906 907 return 0; 908 909 err_usb3v1: 910 regulator_disable(madc->usb3v1); 911 err_i2c: 912 twl4030_madc_set_current_generator(madc, 0, 0); 913 err_current_generator: 914 twl4030_madc_set_power(madc, 0); 915 return ret; 916 } 917 918 static int twl4030_madc_remove(struct platform_device *pdev) 919 { 920 struct iio_dev *iio_dev = platform_get_drvdata(pdev); 921 struct twl4030_madc_data *madc = iio_priv(iio_dev); 922 923 iio_device_unregister(iio_dev); 924 925 twl4030_madc_set_current_generator(madc, 0, 0); 926 twl4030_madc_set_power(madc, 0); 927 928 regulator_disable(madc->usb3v1); 929 930 return 0; 931 } 932 933 #ifdef CONFIG_OF 934 static const struct of_device_id twl_madc_of_match[] = { 935 { .compatible = "ti,twl4030-madc", }, 936 { }, 937 }; 938 MODULE_DEVICE_TABLE(of, twl_madc_of_match); 939 #endif 940 941 static struct platform_driver twl4030_madc_driver = { 942 .probe = twl4030_madc_probe, 943 .remove = twl4030_madc_remove, 944 .driver = { 945 .name = "twl4030_madc", 946 .of_match_table = of_match_ptr(twl_madc_of_match), 947 }, 948 }; 949 950 module_platform_driver(twl4030_madc_driver); 951 952 MODULE_DESCRIPTION("TWL4030 ADC driver"); 953 MODULE_LICENSE("GPL"); 954 MODULE_AUTHOR("J Keerthy"); 955 MODULE_ALIAS("platform:twl4030_madc"); 956