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 - https://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/of.h> 34 #include <linux/regulator/consumer.h> 35 36 #include <linux/iio/iio.h> 37 38 #define TWL4030_MADC_MAX_CHANNELS 16 39 40 #define TWL4030_MADC_CTRL1 0x00 41 #define TWL4030_MADC_CTRL2 0x01 42 43 #define TWL4030_MADC_RTSELECT_LSB 0x02 44 #define TWL4030_MADC_SW1SELECT_LSB 0x06 45 #define TWL4030_MADC_SW2SELECT_LSB 0x0A 46 47 #define TWL4030_MADC_RTAVERAGE_LSB 0x04 48 #define TWL4030_MADC_SW1AVERAGE_LSB 0x08 49 #define TWL4030_MADC_SW2AVERAGE_LSB 0x0C 50 51 #define TWL4030_MADC_CTRL_SW1 0x12 52 #define TWL4030_MADC_CTRL_SW2 0x13 53 54 #define TWL4030_MADC_RTCH0_LSB 0x17 55 #define TWL4030_MADC_GPCH0_LSB 0x37 56 57 #define TWL4030_MADC_MADCON (1 << 0) /* MADC power on */ 58 #define TWL4030_MADC_BUSY (1 << 0) /* MADC busy */ 59 /* MADC conversion completion */ 60 #define TWL4030_MADC_EOC_SW (1 << 1) 61 /* MADC SWx start conversion */ 62 #define TWL4030_MADC_SW_START (1 << 5) 63 #define TWL4030_MADC_ADCIN0 (1 << 0) 64 #define TWL4030_MADC_ADCIN1 (1 << 1) 65 #define TWL4030_MADC_ADCIN2 (1 << 2) 66 #define TWL4030_MADC_ADCIN3 (1 << 3) 67 #define TWL4030_MADC_ADCIN4 (1 << 4) 68 #define TWL4030_MADC_ADCIN5 (1 << 5) 69 #define TWL4030_MADC_ADCIN6 (1 << 6) 70 #define TWL4030_MADC_ADCIN7 (1 << 7) 71 #define TWL4030_MADC_ADCIN8 (1 << 8) 72 #define TWL4030_MADC_ADCIN9 (1 << 9) 73 #define TWL4030_MADC_ADCIN10 (1 << 10) 74 #define TWL4030_MADC_ADCIN11 (1 << 11) 75 #define TWL4030_MADC_ADCIN12 (1 << 12) 76 #define TWL4030_MADC_ADCIN13 (1 << 13) 77 #define TWL4030_MADC_ADCIN14 (1 << 14) 78 #define TWL4030_MADC_ADCIN15 (1 << 15) 79 80 /* Fixed channels */ 81 #define TWL4030_MADC_BTEMP TWL4030_MADC_ADCIN1 82 #define TWL4030_MADC_VBUS TWL4030_MADC_ADCIN8 83 #define TWL4030_MADC_VBKB TWL4030_MADC_ADCIN9 84 #define TWL4030_MADC_ICHG TWL4030_MADC_ADCIN10 85 #define TWL4030_MADC_VCHG TWL4030_MADC_ADCIN11 86 #define TWL4030_MADC_VBAT TWL4030_MADC_ADCIN12 87 88 /* Step size and prescaler ratio */ 89 #define TEMP_STEP_SIZE 147 90 #define TEMP_PSR_R 100 91 #define CURR_STEP_SIZE 147 92 #define CURR_PSR_R1 44 93 #define CURR_PSR_R2 88 94 95 #define TWL4030_BCI_BCICTL1 0x23 96 #define TWL4030_BCI_CGAIN 0x020 97 #define TWL4030_BCI_MESBAT (1 << 1) 98 #define TWL4030_BCI_TYPEN (1 << 4) 99 #define TWL4030_BCI_ITHEN (1 << 3) 100 101 #define REG_BCICTL2 0x024 102 #define TWL4030_BCI_ITHSENS 0x007 103 104 /* Register and bits for GPBR1 register */ 105 #define TWL4030_REG_GPBR1 0x0c 106 #define TWL4030_GPBR1_MADC_HFCLK_EN (1 << 7) 107 108 #define TWL4030_USB_SEL_MADC_MCPC (1<<3) 109 #define TWL4030_USB_CARKIT_ANA_CTRL 0xBB 110 111 struct twl4030_madc_conversion_method { 112 u8 sel; 113 u8 avg; 114 u8 rbase; 115 u8 ctrl; 116 }; 117 118 /** 119 * struct twl4030_madc_request - madc request packet for channel conversion 120 * @channels: 16 bit bitmap for individual channels 121 * @do_avg: sample the input channel for 4 consecutive cycles 122 * @method: RT, SW1, SW2 123 * @type: Polling or interrupt based method 124 * @active: Flag if request is active 125 * @result_pending: Flag from irq handler, that result is ready 126 * @raw: Return raw value, do not convert it 127 * @rbuf: Result buffer 128 */ 129 struct twl4030_madc_request { 130 unsigned long channels; 131 bool do_avg; 132 u16 method; 133 u16 type; 134 bool active; 135 bool result_pending; 136 bool raw; 137 int rbuf[TWL4030_MADC_MAX_CHANNELS]; 138 }; 139 140 enum conversion_methods { 141 TWL4030_MADC_RT, 142 TWL4030_MADC_SW1, 143 TWL4030_MADC_SW2, 144 TWL4030_MADC_NUM_METHODS 145 }; 146 147 enum sample_type { 148 TWL4030_MADC_WAIT, 149 TWL4030_MADC_IRQ_ONESHOT, 150 TWL4030_MADC_IRQ_REARM 151 }; 152 153 /** 154 * struct twl4030_madc_data - a container for madc info 155 * @dev: Pointer to device structure for madc 156 * @lock: Mutex protecting this data structure 157 * @usb3v1: Pointer to bias regulator for madc 158 * @requests: Array of request struct corresponding to SW1, SW2 and RT 159 * @use_second_irq: IRQ selection (main or co-processor) 160 * @imr: Interrupt mask register of MADC 161 * @isr: Interrupt status register of MADC 162 */ 163 struct twl4030_madc_data { 164 struct device *dev; 165 struct mutex lock; 166 struct regulator *usb3v1; 167 struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS]; 168 bool use_second_irq; 169 u8 imr; 170 u8 isr; 171 }; 172 173 static int twl4030_madc_conversion(struct twl4030_madc_request *req); 174 twl4030_madc_read(struct iio_dev * iio_dev,const struct iio_chan_spec * chan,int * val,int * val2,long mask)175 static int twl4030_madc_read(struct iio_dev *iio_dev, 176 const struct iio_chan_spec *chan, 177 int *val, int *val2, long mask) 178 { 179 struct twl4030_madc_data *madc = iio_priv(iio_dev); 180 struct twl4030_madc_request req; 181 int ret; 182 183 req.method = madc->use_second_irq ? TWL4030_MADC_SW2 : TWL4030_MADC_SW1; 184 185 req.channels = BIT(chan->channel); 186 req.active = false; 187 req.type = TWL4030_MADC_WAIT; 188 req.raw = !(mask == IIO_CHAN_INFO_PROCESSED); 189 req.do_avg = (mask == IIO_CHAN_INFO_AVERAGE_RAW); 190 191 ret = twl4030_madc_conversion(&req); 192 if (ret < 0) 193 return ret; 194 195 *val = req.rbuf[chan->channel]; 196 197 return IIO_VAL_INT; 198 } 199 200 static const struct iio_info twl4030_madc_iio_info = { 201 .read_raw = &twl4030_madc_read, 202 }; 203 204 #define TWL4030_ADC_CHANNEL(_channel, _type, _name) { \ 205 .type = _type, \ 206 .channel = _channel, \ 207 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 208 BIT(IIO_CHAN_INFO_AVERAGE_RAW) | \ 209 BIT(IIO_CHAN_INFO_PROCESSED), \ 210 .datasheet_name = _name, \ 211 .indexed = 1, \ 212 } 213 214 static const struct iio_chan_spec twl4030_madc_iio_channels[] = { 215 TWL4030_ADC_CHANNEL(0, IIO_VOLTAGE, "ADCIN0"), 216 TWL4030_ADC_CHANNEL(1, IIO_TEMP, "ADCIN1"), 217 TWL4030_ADC_CHANNEL(2, IIO_VOLTAGE, "ADCIN2"), 218 TWL4030_ADC_CHANNEL(3, IIO_VOLTAGE, "ADCIN3"), 219 TWL4030_ADC_CHANNEL(4, IIO_VOLTAGE, "ADCIN4"), 220 TWL4030_ADC_CHANNEL(5, IIO_VOLTAGE, "ADCIN5"), 221 TWL4030_ADC_CHANNEL(6, IIO_VOLTAGE, "ADCIN6"), 222 TWL4030_ADC_CHANNEL(7, IIO_VOLTAGE, "ADCIN7"), 223 TWL4030_ADC_CHANNEL(8, IIO_VOLTAGE, "ADCIN8"), 224 TWL4030_ADC_CHANNEL(9, IIO_VOLTAGE, "ADCIN9"), 225 TWL4030_ADC_CHANNEL(10, IIO_CURRENT, "ADCIN10"), 226 TWL4030_ADC_CHANNEL(11, IIO_VOLTAGE, "ADCIN11"), 227 TWL4030_ADC_CHANNEL(12, IIO_VOLTAGE, "ADCIN12"), 228 TWL4030_ADC_CHANNEL(13, IIO_VOLTAGE, "ADCIN13"), 229 TWL4030_ADC_CHANNEL(14, IIO_VOLTAGE, "ADCIN14"), 230 TWL4030_ADC_CHANNEL(15, IIO_VOLTAGE, "ADCIN15"), 231 }; 232 233 static struct twl4030_madc_data *twl4030_madc; 234 235 static const struct s16_fract twl4030_divider_ratios[16] = { 236 {1, 1}, /* CHANNEL 0 No Prescaler */ 237 {1, 1}, /* CHANNEL 1 No Prescaler */ 238 {6, 10}, /* CHANNEL 2 */ 239 {6, 10}, /* CHANNEL 3 */ 240 {6, 10}, /* CHANNEL 4 */ 241 {6, 10}, /* CHANNEL 5 */ 242 {6, 10}, /* CHANNEL 6 */ 243 {6, 10}, /* CHANNEL 7 */ 244 {3, 14}, /* CHANNEL 8 */ 245 {1, 3}, /* CHANNEL 9 */ 246 {1, 1}, /* CHANNEL 10 No Prescaler */ 247 {15, 100}, /* CHANNEL 11 */ 248 {1, 4}, /* CHANNEL 12 */ 249 {1, 1}, /* CHANNEL 13 Reserved channels */ 250 {1, 1}, /* CHANNEL 14 Reseved channels */ 251 {5, 11}, /* CHANNEL 15 */ 252 }; 253 254 /* Conversion table from -3 to 55 degrees Celcius */ 255 static int twl4030_therm_tbl[] = { 256 30800, 29500, 28300, 27100, 257 26000, 24900, 23900, 22900, 22000, 21100, 20300, 19400, 18700, 258 17900, 17200, 16500, 15900, 15300, 14700, 14100, 13600, 13100, 259 12600, 12100, 11600, 11200, 10800, 10400, 10000, 9630, 9280, 260 8950, 8620, 8310, 8020, 7730, 7460, 7200, 6950, 6710, 261 6470, 6250, 6040, 5830, 5640, 5450, 5260, 5090, 4920, 262 4760, 4600, 4450, 4310, 4170, 4040, 3910, 3790, 3670, 263 3550 264 }; 265 266 /* 267 * Structure containing the registers 268 * of different conversion methods supported by MADC. 269 * Hardware or RT real time conversion request initiated by external host 270 * processor for RT Signal conversions. 271 * External host processors can also request for non RT conversions 272 * SW1 and SW2 software conversions also called asynchronous or GPC request. 273 */ 274 static 275 const struct twl4030_madc_conversion_method twl4030_conversion_methods[] = { 276 [TWL4030_MADC_RT] = { 277 .sel = TWL4030_MADC_RTSELECT_LSB, 278 .avg = TWL4030_MADC_RTAVERAGE_LSB, 279 .rbase = TWL4030_MADC_RTCH0_LSB, 280 }, 281 [TWL4030_MADC_SW1] = { 282 .sel = TWL4030_MADC_SW1SELECT_LSB, 283 .avg = TWL4030_MADC_SW1AVERAGE_LSB, 284 .rbase = TWL4030_MADC_GPCH0_LSB, 285 .ctrl = TWL4030_MADC_CTRL_SW1, 286 }, 287 [TWL4030_MADC_SW2] = { 288 .sel = TWL4030_MADC_SW2SELECT_LSB, 289 .avg = TWL4030_MADC_SW2AVERAGE_LSB, 290 .rbase = TWL4030_MADC_GPCH0_LSB, 291 .ctrl = TWL4030_MADC_CTRL_SW2, 292 }, 293 }; 294 295 /** 296 * twl4030_madc_channel_raw_read() - Function to read a particular channel value 297 * @madc: pointer to struct twl4030_madc_data 298 * @reg: lsb of ADC Channel 299 * 300 * Return: 0 on success, an error code otherwise. 301 */ twl4030_madc_channel_raw_read(struct twl4030_madc_data * madc,u8 reg)302 static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg) 303 { 304 u16 val; 305 int ret; 306 /* 307 * For each ADC channel, we have MSB and LSB register pair. MSB address 308 * is always LSB address+1. reg parameter is the address of LSB register 309 */ 310 ret = twl_i2c_read_u16(TWL4030_MODULE_MADC, &val, reg); 311 if (ret) { 312 dev_err(madc->dev, "unable to read register 0x%X\n", reg); 313 return ret; 314 } 315 316 return (int)(val >> 6); 317 } 318 319 /* 320 * Return battery temperature in degrees Celsius 321 * Or < 0 on failure. 322 */ twl4030battery_temperature(int raw_volt)323 static int twl4030battery_temperature(int raw_volt) 324 { 325 u8 val; 326 int temp, curr, volt, res, ret; 327 328 volt = (raw_volt * TEMP_STEP_SIZE) / TEMP_PSR_R; 329 /* Getting and calculating the supply current in micro amperes */ 330 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, &val, 331 REG_BCICTL2); 332 if (ret < 0) 333 return ret; 334 335 curr = ((val & TWL4030_BCI_ITHSENS) + 1) * 10; 336 /* Getting and calculating the thermistor resistance in ohms */ 337 res = volt * 1000 / curr; 338 /* calculating temperature */ 339 for (temp = 58; temp >= 0; temp--) { 340 int actual = twl4030_therm_tbl[temp]; 341 if ((actual - res) >= 0) 342 break; 343 } 344 345 return temp + 1; 346 } 347 twl4030battery_current(int raw_volt)348 static int twl4030battery_current(int raw_volt) 349 { 350 int ret; 351 u8 val; 352 353 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, &val, 354 TWL4030_BCI_BCICTL1); 355 if (ret) 356 return ret; 357 if (val & TWL4030_BCI_CGAIN) /* slope of 0.44 mV/mA */ 358 return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R1; 359 else /* slope of 0.88 mV/mA */ 360 return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R2; 361 } 362 363 /* 364 * Function to read channel values 365 * @madc - pointer to twl4030_madc_data struct 366 * @reg_base - Base address of the first channel 367 * @Channels - 16 bit bitmap. If the bit is set, channel's value is read 368 * @buf - The channel values are stored here. if read fails error 369 * @raw - Return raw values without conversion 370 * value is stored 371 * Returns the number of successfully read channels. 372 */ twl4030_madc_read_channels(struct twl4030_madc_data * madc,u8 reg_base,unsigned long channels,int * buf,bool raw)373 static int twl4030_madc_read_channels(struct twl4030_madc_data *madc, 374 u8 reg_base, unsigned 375 long channels, int *buf, 376 bool raw) 377 { 378 int count = 0; 379 int i; 380 u8 reg; 381 382 for_each_set_bit(i, &channels, TWL4030_MADC_MAX_CHANNELS) { 383 reg = reg_base + (2 * i); 384 buf[i] = twl4030_madc_channel_raw_read(madc, reg); 385 if (buf[i] < 0) { 386 dev_err(madc->dev, "Unable to read register 0x%X\n", 387 reg); 388 return buf[i]; 389 } 390 if (raw) { 391 count++; 392 continue; 393 } 394 switch (i) { 395 case 10: 396 buf[i] = twl4030battery_current(buf[i]); 397 if (buf[i] < 0) { 398 dev_err(madc->dev, "err reading current\n"); 399 return buf[i]; 400 } else { 401 count++; 402 buf[i] = buf[i] - 750; 403 } 404 break; 405 case 1: 406 buf[i] = twl4030battery_temperature(buf[i]); 407 if (buf[i] < 0) { 408 dev_err(madc->dev, "err reading temperature\n"); 409 return buf[i]; 410 } else { 411 buf[i] -= 3; 412 count++; 413 } 414 break; 415 default: 416 count++; 417 /* Analog Input (V) = conv_result * step_size / R 418 * conv_result = decimal value of 10-bit conversion 419 * result 420 * step size = 1.5 / (2 ^ 10 -1) 421 * R = Prescaler ratio for input channels. 422 * Result given in mV hence multiplied by 1000. 423 */ 424 buf[i] = (buf[i] * 3 * 1000 * 425 twl4030_divider_ratios[i].denominator) 426 / (2 * 1023 * 427 twl4030_divider_ratios[i].numerator); 428 } 429 } 430 431 return count; 432 } 433 434 /* 435 * Disables irq. 436 * @madc - pointer to twl4030_madc_data struct 437 * @id - irq number to be disabled 438 * can take one of TWL4030_MADC_RT, TWL4030_MADC_SW1, TWL4030_MADC_SW2 439 * corresponding to RT, SW1, SW2 conversion requests. 440 * Returns error if i2c read/write fails. 441 */ twl4030_madc_disable_irq(struct twl4030_madc_data * madc,u8 id)442 static int twl4030_madc_disable_irq(struct twl4030_madc_data *madc, u8 id) 443 { 444 u8 val; 445 int ret; 446 447 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &val, madc->imr); 448 if (ret) { 449 dev_err(madc->dev, "unable to read imr register 0x%X\n", 450 madc->imr); 451 return ret; 452 } 453 val |= (1 << id); 454 ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, val, madc->imr); 455 if (ret) { 456 dev_err(madc->dev, 457 "unable to write imr register 0x%X\n", madc->imr); 458 return ret; 459 } 460 461 return 0; 462 } 463 twl4030_madc_threaded_irq_handler(int irq,void * _madc)464 static irqreturn_t twl4030_madc_threaded_irq_handler(int irq, void *_madc) 465 { 466 struct twl4030_madc_data *madc = _madc; 467 const struct twl4030_madc_conversion_method *method; 468 u8 isr_val, imr_val; 469 int i, ret; 470 struct twl4030_madc_request *r; 471 472 mutex_lock(&madc->lock); 473 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &isr_val, madc->isr); 474 if (ret) { 475 dev_err(madc->dev, "unable to read isr register 0x%X\n", 476 madc->isr); 477 goto err_i2c; 478 } 479 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &imr_val, madc->imr); 480 if (ret) { 481 dev_err(madc->dev, "unable to read imr register 0x%X\n", 482 madc->imr); 483 goto err_i2c; 484 } 485 isr_val &= ~imr_val; 486 for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) { 487 if (!(isr_val & (1 << i))) 488 continue; 489 ret = twl4030_madc_disable_irq(madc, i); 490 if (ret < 0) 491 dev_dbg(madc->dev, "Disable interrupt failed %d\n", i); 492 madc->requests[i].result_pending = true; 493 } 494 for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) { 495 r = &madc->requests[i]; 496 /* No pending results for this method, move to next one */ 497 if (!r->result_pending) 498 continue; 499 method = &twl4030_conversion_methods[r->method]; 500 /* Read results */ 501 twl4030_madc_read_channels(madc, method->rbase, 502 r->channels, r->rbuf, r->raw); 503 /* Free request */ 504 r->result_pending = false; 505 r->active = false; 506 } 507 mutex_unlock(&madc->lock); 508 509 return IRQ_HANDLED; 510 511 err_i2c: 512 /* 513 * In case of error check whichever request is active 514 * and service the same. 515 */ 516 for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) { 517 r = &madc->requests[i]; 518 if (!r->active) 519 continue; 520 method = &twl4030_conversion_methods[r->method]; 521 /* Read results */ 522 twl4030_madc_read_channels(madc, method->rbase, 523 r->channels, r->rbuf, r->raw); 524 /* Free request */ 525 r->result_pending = false; 526 r->active = false; 527 } 528 mutex_unlock(&madc->lock); 529 530 return IRQ_HANDLED; 531 } 532 533 /* 534 * Function which enables the madc conversion 535 * by writing to the control register. 536 * @madc - pointer to twl4030_madc_data struct 537 * @conv_method - can be TWL4030_MADC_RT, TWL4030_MADC_SW2, TWL4030_MADC_SW1 538 * corresponding to RT SW1 or SW2 conversion methods. 539 * Returns 0 if succeeds else a negative error value 540 */ twl4030_madc_start_conversion(struct twl4030_madc_data * madc,int conv_method)541 static int twl4030_madc_start_conversion(struct twl4030_madc_data *madc, 542 int conv_method) 543 { 544 const struct twl4030_madc_conversion_method *method; 545 int ret = 0; 546 547 if (conv_method != TWL4030_MADC_SW1 && conv_method != TWL4030_MADC_SW2) 548 return -ENOTSUPP; 549 550 method = &twl4030_conversion_methods[conv_method]; 551 ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, TWL4030_MADC_SW_START, 552 method->ctrl); 553 if (ret) { 554 dev_err(madc->dev, "unable to write ctrl register 0x%X\n", 555 method->ctrl); 556 return ret; 557 } 558 559 return 0; 560 } 561 562 /* 563 * Function that waits for conversion to be ready 564 * @madc - pointer to twl4030_madc_data struct 565 * @timeout_ms - timeout value in milliseconds 566 * @status_reg - ctrl register 567 * returns 0 if succeeds else a negative error value 568 */ twl4030_madc_wait_conversion_ready(struct twl4030_madc_data * madc,unsigned int timeout_ms,u8 status_reg)569 static int twl4030_madc_wait_conversion_ready(struct twl4030_madc_data *madc, 570 unsigned int timeout_ms, 571 u8 status_reg) 572 { 573 unsigned long timeout; 574 int ret; 575 576 timeout = jiffies + msecs_to_jiffies(timeout_ms); 577 do { 578 u8 reg; 579 580 ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, ®, status_reg); 581 if (ret) { 582 dev_err(madc->dev, 583 "unable to read status register 0x%X\n", 584 status_reg); 585 return ret; 586 } 587 if (!(reg & TWL4030_MADC_BUSY) && (reg & TWL4030_MADC_EOC_SW)) 588 return 0; 589 usleep_range(500, 2000); 590 } while (!time_after(jiffies, timeout)); 591 dev_err(madc->dev, "conversion timeout!\n"); 592 593 return -EAGAIN; 594 } 595 596 /* 597 * An exported function which can be called from other kernel drivers. 598 * @req twl4030_madc_request structure 599 * req->rbuf will be filled with read values of channels based on the 600 * channel index. If a particular channel reading fails there will 601 * be a negative error value in the corresponding array element. 602 * returns 0 if succeeds else error value 603 */ twl4030_madc_conversion(struct twl4030_madc_request * req)604 static int twl4030_madc_conversion(struct twl4030_madc_request *req) 605 { 606 const struct twl4030_madc_conversion_method *method; 607 int ret; 608 609 if (!req || !twl4030_madc) 610 return -EINVAL; 611 612 mutex_lock(&twl4030_madc->lock); 613 if (req->method < TWL4030_MADC_RT || req->method > TWL4030_MADC_SW2) { 614 ret = -EINVAL; 615 goto out; 616 } 617 /* Do we have a conversion request ongoing */ 618 if (twl4030_madc->requests[req->method].active) { 619 ret = -EBUSY; 620 goto out; 621 } 622 method = &twl4030_conversion_methods[req->method]; 623 /* Select channels to be converted */ 624 ret = twl_i2c_write_u16(TWL4030_MODULE_MADC, req->channels, method->sel); 625 if (ret) { 626 dev_err(twl4030_madc->dev, 627 "unable to write sel register 0x%X\n", method->sel); 628 goto out; 629 } 630 /* Select averaging for all channels if do_avg is set */ 631 if (req->do_avg) { 632 ret = twl_i2c_write_u16(TWL4030_MODULE_MADC, req->channels, 633 method->avg); 634 if (ret) { 635 dev_err(twl4030_madc->dev, 636 "unable to write avg register 0x%X\n", 637 method->avg); 638 goto out; 639 } 640 } 641 /* With RT method we should not be here anymore */ 642 if (req->method == TWL4030_MADC_RT) { 643 ret = -EINVAL; 644 goto out; 645 } 646 ret = twl4030_madc_start_conversion(twl4030_madc, req->method); 647 if (ret < 0) 648 goto out; 649 twl4030_madc->requests[req->method].active = true; 650 /* Wait until conversion is ready (ctrl register returns EOC) */ 651 ret = twl4030_madc_wait_conversion_ready(twl4030_madc, 5, method->ctrl); 652 if (ret) { 653 twl4030_madc->requests[req->method].active = false; 654 goto out; 655 } 656 ret = twl4030_madc_read_channels(twl4030_madc, method->rbase, 657 req->channels, req->rbuf, req->raw); 658 twl4030_madc->requests[req->method].active = false; 659 660 out: 661 mutex_unlock(&twl4030_madc->lock); 662 663 return ret; 664 } 665 666 /** 667 * twl4030_madc_set_current_generator() - setup bias current 668 * 669 * @madc: pointer to twl4030_madc_data struct 670 * @chan: can be one of the two values: 671 * 0 - Enables bias current for main battery type reading 672 * 1 - Enables bias current for main battery temperature sensing 673 * @on: enable or disable chan. 674 * 675 * Function to enable or disable bias current for 676 * main battery type reading or temperature sensing 677 */ twl4030_madc_set_current_generator(struct twl4030_madc_data * madc,int chan,int on)678 static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc, 679 int chan, int on) 680 { 681 int ret; 682 int regmask; 683 u8 regval; 684 685 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, 686 ®val, TWL4030_BCI_BCICTL1); 687 if (ret) { 688 dev_err(madc->dev, "unable to read BCICTL1 reg 0x%X", 689 TWL4030_BCI_BCICTL1); 690 return ret; 691 } 692 693 regmask = chan ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN; 694 if (on) 695 regval |= regmask; 696 else 697 regval &= ~regmask; 698 699 ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 700 regval, TWL4030_BCI_BCICTL1); 701 if (ret) { 702 dev_err(madc->dev, "unable to write BCICTL1 reg 0x%X\n", 703 TWL4030_BCI_BCICTL1); 704 return ret; 705 } 706 707 return 0; 708 } 709 710 /* 711 * Function that sets MADC software power on bit to enable MADC 712 * @madc - pointer to twl4030_madc_data struct 713 * @on - Enable or disable MADC software power on bit. 714 * returns error if i2c read/write fails else 0 715 */ twl4030_madc_set_power(struct twl4030_madc_data * madc,int on)716 static int twl4030_madc_set_power(struct twl4030_madc_data *madc, int on) 717 { 718 u8 regval; 719 int ret; 720 721 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, 722 ®val, TWL4030_MADC_CTRL1); 723 if (ret) { 724 dev_err(madc->dev, "unable to read madc ctrl1 reg 0x%X\n", 725 TWL4030_MADC_CTRL1); 726 return ret; 727 } 728 if (on) 729 regval |= TWL4030_MADC_MADCON; 730 else 731 regval &= ~TWL4030_MADC_MADCON; 732 ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, regval, TWL4030_MADC_CTRL1); 733 if (ret) { 734 dev_err(madc->dev, "unable to write madc ctrl1 reg 0x%X\n", 735 TWL4030_MADC_CTRL1); 736 return ret; 737 } 738 739 return 0; 740 } 741 742 /* 743 * Initialize MADC and request for threaded irq 744 */ twl4030_madc_probe(struct platform_device * pdev)745 static int twl4030_madc_probe(struct platform_device *pdev) 746 { 747 struct twl4030_madc_data *madc; 748 struct twl4030_madc_platform_data *pdata = dev_get_platdata(&pdev->dev); 749 struct device_node *np = pdev->dev.of_node; 750 int irq, ret; 751 u8 regval; 752 struct iio_dev *iio_dev = NULL; 753 754 if (!pdata && !np) { 755 dev_err(&pdev->dev, "neither platform data nor Device Tree node available\n"); 756 return -EINVAL; 757 } 758 759 iio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*madc)); 760 if (!iio_dev) { 761 dev_err(&pdev->dev, "failed allocating iio device\n"); 762 return -ENOMEM; 763 } 764 765 madc = iio_priv(iio_dev); 766 madc->dev = &pdev->dev; 767 768 iio_dev->name = dev_name(&pdev->dev); 769 iio_dev->info = &twl4030_madc_iio_info; 770 iio_dev->modes = INDIO_DIRECT_MODE; 771 iio_dev->channels = twl4030_madc_iio_channels; 772 iio_dev->num_channels = ARRAY_SIZE(twl4030_madc_iio_channels); 773 774 /* 775 * Phoenix provides 2 interrupt lines. The first one is connected to 776 * the OMAP. The other one can be connected to the other processor such 777 * as modem. Hence two separate ISR and IMR registers. 778 */ 779 if (pdata) 780 madc->use_second_irq = (pdata->irq_line != 1); 781 else 782 madc->use_second_irq = of_property_read_bool(np, 783 "ti,system-uses-second-madc-irq"); 784 785 madc->imr = madc->use_second_irq ? TWL4030_MADC_IMR2 : 786 TWL4030_MADC_IMR1; 787 madc->isr = madc->use_second_irq ? TWL4030_MADC_ISR2 : 788 TWL4030_MADC_ISR1; 789 790 ret = twl4030_madc_set_power(madc, 1); 791 if (ret < 0) 792 return ret; 793 ret = twl4030_madc_set_current_generator(madc, 0, 1); 794 if (ret < 0) 795 goto err_current_generator; 796 797 ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, 798 ®val, TWL4030_BCI_BCICTL1); 799 if (ret) { 800 dev_err(&pdev->dev, "unable to read reg BCI CTL1 0x%X\n", 801 TWL4030_BCI_BCICTL1); 802 goto err_i2c; 803 } 804 regval |= TWL4030_BCI_MESBAT; 805 ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE, 806 regval, TWL4030_BCI_BCICTL1); 807 if (ret) { 808 dev_err(&pdev->dev, "unable to write reg BCI Ctl1 0x%X\n", 809 TWL4030_BCI_BCICTL1); 810 goto err_i2c; 811 } 812 813 /* Check that MADC clock is on */ 814 ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, ®val, TWL4030_REG_GPBR1); 815 if (ret) { 816 dev_err(&pdev->dev, "unable to read reg GPBR1 0x%X\n", 817 TWL4030_REG_GPBR1); 818 goto err_i2c; 819 } 820 821 /* If MADC clk is not on, turn it on */ 822 if (!(regval & TWL4030_GPBR1_MADC_HFCLK_EN)) { 823 dev_info(&pdev->dev, "clk disabled, enabling\n"); 824 regval |= TWL4030_GPBR1_MADC_HFCLK_EN; 825 ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, regval, 826 TWL4030_REG_GPBR1); 827 if (ret) { 828 dev_err(&pdev->dev, "unable to write reg GPBR1 0x%X\n", 829 TWL4030_REG_GPBR1); 830 goto err_i2c; 831 } 832 } 833 834 platform_set_drvdata(pdev, iio_dev); 835 mutex_init(&madc->lock); 836 837 irq = platform_get_irq(pdev, 0); 838 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, 839 twl4030_madc_threaded_irq_handler, 840 IRQF_TRIGGER_RISING | IRQF_ONESHOT, 841 "twl4030_madc", madc); 842 if (ret) { 843 dev_err(&pdev->dev, "could not request irq\n"); 844 goto err_i2c; 845 } 846 twl4030_madc = madc; 847 848 /* Configure MADC[3:6] */ 849 ret = twl_i2c_read_u8(TWL_MODULE_USB, ®val, 850 TWL4030_USB_CARKIT_ANA_CTRL); 851 if (ret) { 852 dev_err(&pdev->dev, "unable to read reg CARKIT_ANA_CTRL 0x%X\n", 853 TWL4030_USB_CARKIT_ANA_CTRL); 854 goto err_i2c; 855 } 856 regval |= TWL4030_USB_SEL_MADC_MCPC; 857 ret = twl_i2c_write_u8(TWL_MODULE_USB, regval, 858 TWL4030_USB_CARKIT_ANA_CTRL); 859 if (ret) { 860 dev_err(&pdev->dev, "unable to write reg CARKIT_ANA_CTRL 0x%X\n", 861 TWL4030_USB_CARKIT_ANA_CTRL); 862 goto err_i2c; 863 } 864 865 /* Enable 3v1 bias regulator for MADC[3:6] */ 866 madc->usb3v1 = devm_regulator_get(madc->dev, "vusb3v1"); 867 if (IS_ERR(madc->usb3v1)) { 868 ret = -ENODEV; 869 goto err_i2c; 870 } 871 872 ret = regulator_enable(madc->usb3v1); 873 if (ret) { 874 dev_err(madc->dev, "could not enable 3v1 bias regulator\n"); 875 goto err_i2c; 876 } 877 878 ret = iio_device_register(iio_dev); 879 if (ret) { 880 dev_err(&pdev->dev, "could not register iio device\n"); 881 goto err_usb3v1; 882 } 883 884 return 0; 885 886 err_usb3v1: 887 regulator_disable(madc->usb3v1); 888 err_i2c: 889 twl4030_madc_set_current_generator(madc, 0, 0); 890 err_current_generator: 891 twl4030_madc_set_power(madc, 0); 892 return ret; 893 } 894 twl4030_madc_remove(struct platform_device * pdev)895 static int twl4030_madc_remove(struct platform_device *pdev) 896 { 897 struct iio_dev *iio_dev = platform_get_drvdata(pdev); 898 struct twl4030_madc_data *madc = iio_priv(iio_dev); 899 900 iio_device_unregister(iio_dev); 901 902 twl4030_madc_set_current_generator(madc, 0, 0); 903 twl4030_madc_set_power(madc, 0); 904 905 regulator_disable(madc->usb3v1); 906 907 return 0; 908 } 909 910 #ifdef CONFIG_OF 911 static const struct of_device_id twl_madc_of_match[] = { 912 { .compatible = "ti,twl4030-madc", }, 913 { }, 914 }; 915 MODULE_DEVICE_TABLE(of, twl_madc_of_match); 916 #endif 917 918 static struct platform_driver twl4030_madc_driver = { 919 .probe = twl4030_madc_probe, 920 .remove = twl4030_madc_remove, 921 .driver = { 922 .name = "twl4030_madc", 923 .of_match_table = of_match_ptr(twl_madc_of_match), 924 }, 925 }; 926 927 module_platform_driver(twl4030_madc_driver); 928 929 MODULE_DESCRIPTION("TWL4030 ADC driver"); 930 MODULE_LICENSE("GPL"); 931 MODULE_AUTHOR("J Keerthy"); 932 MODULE_ALIAS("platform:twl4030_madc"); 933