1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Freescale Vybrid vf610 ADC driver 4 * 5 * Copyright 2013 Freescale Semiconductor, Inc. 6 */ 7 8 #include <linux/module.h> 9 #include <linux/platform_device.h> 10 #include <linux/interrupt.h> 11 #include <linux/delay.h> 12 #include <linux/kernel.h> 13 #include <linux/slab.h> 14 #include <linux/io.h> 15 #include <linux/clk.h> 16 #include <linux/completion.h> 17 #include <linux/of.h> 18 #include <linux/of_irq.h> 19 #include <linux/regulator/consumer.h> 20 #include <linux/of_platform.h> 21 #include <linux/err.h> 22 23 #include <linux/iio/iio.h> 24 #include <linux/iio/buffer.h> 25 #include <linux/iio/sysfs.h> 26 #include <linux/iio/trigger.h> 27 #include <linux/iio/trigger_consumer.h> 28 #include <linux/iio/triggered_buffer.h> 29 30 /* This will be the driver name the kernel reports */ 31 #define DRIVER_NAME "vf610-adc" 32 33 /* Vybrid/IMX ADC registers */ 34 #define VF610_REG_ADC_HC0 0x00 35 #define VF610_REG_ADC_HC1 0x04 36 #define VF610_REG_ADC_HS 0x08 37 #define VF610_REG_ADC_R0 0x0c 38 #define VF610_REG_ADC_R1 0x10 39 #define VF610_REG_ADC_CFG 0x14 40 #define VF610_REG_ADC_GC 0x18 41 #define VF610_REG_ADC_GS 0x1c 42 #define VF610_REG_ADC_CV 0x20 43 #define VF610_REG_ADC_OFS 0x24 44 #define VF610_REG_ADC_CAL 0x28 45 #define VF610_REG_ADC_PCTL 0x30 46 47 /* Configuration register field define */ 48 #define VF610_ADC_MODE_BIT8 0x00 49 #define VF610_ADC_MODE_BIT10 0x04 50 #define VF610_ADC_MODE_BIT12 0x08 51 #define VF610_ADC_MODE_MASK 0x0c 52 #define VF610_ADC_BUSCLK2_SEL 0x01 53 #define VF610_ADC_ALTCLK_SEL 0x02 54 #define VF610_ADC_ADACK_SEL 0x03 55 #define VF610_ADC_ADCCLK_MASK 0x03 56 #define VF610_ADC_CLK_DIV2 0x20 57 #define VF610_ADC_CLK_DIV4 0x40 58 #define VF610_ADC_CLK_DIV8 0x60 59 #define VF610_ADC_CLK_MASK 0x60 60 #define VF610_ADC_ADLSMP_LONG 0x10 61 #define VF610_ADC_ADSTS_SHORT 0x100 62 #define VF610_ADC_ADSTS_NORMAL 0x200 63 #define VF610_ADC_ADSTS_LONG 0x300 64 #define VF610_ADC_ADSTS_MASK 0x300 65 #define VF610_ADC_ADLPC_EN 0x80 66 #define VF610_ADC_ADHSC_EN 0x400 67 #define VF610_ADC_REFSEL_VALT 0x800 68 #define VF610_ADC_REFSEL_VBG 0x1000 69 #define VF610_ADC_ADTRG_HARD 0x2000 70 #define VF610_ADC_AVGS_8 0x4000 71 #define VF610_ADC_AVGS_16 0x8000 72 #define VF610_ADC_AVGS_32 0xC000 73 #define VF610_ADC_AVGS_MASK 0xC000 74 #define VF610_ADC_OVWREN 0x10000 75 76 /* General control register field define */ 77 #define VF610_ADC_ADACKEN 0x1 78 #define VF610_ADC_DMAEN 0x2 79 #define VF610_ADC_ACREN 0x4 80 #define VF610_ADC_ACFGT 0x8 81 #define VF610_ADC_ACFE 0x10 82 #define VF610_ADC_AVGEN 0x20 83 #define VF610_ADC_ADCON 0x40 84 #define VF610_ADC_CAL 0x80 85 86 /* Other field define */ 87 #define VF610_ADC_ADCHC(x) ((x) & 0x1F) 88 #define VF610_ADC_AIEN (0x1 << 7) 89 #define VF610_ADC_CONV_DISABLE 0x1F 90 #define VF610_ADC_HS_COCO0 0x1 91 #define VF610_ADC_CALF 0x2 92 #define VF610_ADC_TIMEOUT msecs_to_jiffies(100) 93 94 #define DEFAULT_SAMPLE_TIME 1000 95 96 /* V at 25°C of 696 mV */ 97 #define VF610_VTEMP25_3V0 950 98 /* V at 25°C of 699 mV */ 99 #define VF610_VTEMP25_3V3 867 100 /* Typical sensor slope coefficient at all temperatures */ 101 #define VF610_TEMP_SLOPE_COEFF 1840 102 103 enum clk_sel { 104 VF610_ADCIOC_BUSCLK_SET, 105 VF610_ADCIOC_ALTCLK_SET, 106 VF610_ADCIOC_ADACK_SET, 107 }; 108 109 enum vol_ref { 110 VF610_ADCIOC_VR_VREF_SET, 111 VF610_ADCIOC_VR_VALT_SET, 112 VF610_ADCIOC_VR_VBG_SET, 113 }; 114 115 enum average_sel { 116 VF610_ADC_SAMPLE_1, 117 VF610_ADC_SAMPLE_4, 118 VF610_ADC_SAMPLE_8, 119 VF610_ADC_SAMPLE_16, 120 VF610_ADC_SAMPLE_32, 121 }; 122 123 enum conversion_mode_sel { 124 VF610_ADC_CONV_NORMAL, 125 VF610_ADC_CONV_HIGH_SPEED, 126 VF610_ADC_CONV_LOW_POWER, 127 }; 128 129 enum lst_adder_sel { 130 VF610_ADCK_CYCLES_3, 131 VF610_ADCK_CYCLES_5, 132 VF610_ADCK_CYCLES_7, 133 VF610_ADCK_CYCLES_9, 134 VF610_ADCK_CYCLES_13, 135 VF610_ADCK_CYCLES_17, 136 VF610_ADCK_CYCLES_21, 137 VF610_ADCK_CYCLES_25, 138 }; 139 140 struct vf610_adc_feature { 141 enum clk_sel clk_sel; 142 enum vol_ref vol_ref; 143 enum conversion_mode_sel conv_mode; 144 145 int clk_div; 146 int sample_rate; 147 int res_mode; 148 u32 lst_adder_index; 149 u32 default_sample_time; 150 151 bool calibration; 152 bool ovwren; 153 }; 154 155 struct vf610_adc { 156 struct device *dev; 157 void __iomem *regs; 158 struct clk *clk; 159 160 u32 vref_uv; 161 u32 value; 162 struct regulator *vref; 163 164 u32 max_adck_rate[3]; 165 struct vf610_adc_feature adc_feature; 166 167 u32 sample_freq_avail[5]; 168 169 struct completion completion; 170 u16 buffer[8]; 171 }; 172 173 static const u32 vf610_hw_avgs[] = { 1, 4, 8, 16, 32 }; 174 static const u32 vf610_lst_adder[] = { 3, 5, 7, 9, 13, 17, 21, 25 }; 175 176 static inline void vf610_adc_calculate_rates(struct vf610_adc *info) 177 { 178 struct vf610_adc_feature *adc_feature = &info->adc_feature; 179 unsigned long adck_rate, ipg_rate = clk_get_rate(info->clk); 180 u32 adck_period, lst_addr_min; 181 int divisor, i; 182 183 adck_rate = info->max_adck_rate[adc_feature->conv_mode]; 184 185 if (adck_rate) { 186 /* calculate clk divider which is within specification */ 187 divisor = ipg_rate / adck_rate; 188 adc_feature->clk_div = 1 << fls(divisor + 1); 189 } else { 190 /* fall-back value using a safe divisor */ 191 adc_feature->clk_div = 8; 192 } 193 194 adck_rate = ipg_rate / adc_feature->clk_div; 195 196 /* 197 * Determine the long sample time adder value to be used based 198 * on the default minimum sample time provided. 199 */ 200 adck_period = NSEC_PER_SEC / adck_rate; 201 lst_addr_min = adc_feature->default_sample_time / adck_period; 202 for (i = 0; i < ARRAY_SIZE(vf610_lst_adder); i++) { 203 if (vf610_lst_adder[i] > lst_addr_min) { 204 adc_feature->lst_adder_index = i; 205 break; 206 } 207 } 208 209 /* 210 * Calculate ADC sample frequencies 211 * Sample time unit is ADCK cycles. ADCK clk source is ipg clock, 212 * which is the same as bus clock. 213 * 214 * ADC conversion time = SFCAdder + AverageNum x (BCT + LSTAdder) 215 * SFCAdder: fixed to 6 ADCK cycles 216 * AverageNum: 1, 4, 8, 16, 32 samples for hardware average. 217 * BCT (Base Conversion Time): fixed to 25 ADCK cycles for 12 bit mode 218 * LSTAdder(Long Sample Time): 3, 5, 7, 9, 13, 17, 21, 25 ADCK cycles 219 */ 220 for (i = 0; i < ARRAY_SIZE(vf610_hw_avgs); i++) 221 info->sample_freq_avail[i] = 222 adck_rate / (6 + vf610_hw_avgs[i] * 223 (25 + vf610_lst_adder[adc_feature->lst_adder_index])); 224 } 225 226 static inline void vf610_adc_cfg_init(struct vf610_adc *info) 227 { 228 struct vf610_adc_feature *adc_feature = &info->adc_feature; 229 230 /* set default Configuration for ADC controller */ 231 adc_feature->clk_sel = VF610_ADCIOC_BUSCLK_SET; 232 adc_feature->vol_ref = VF610_ADCIOC_VR_VREF_SET; 233 234 adc_feature->calibration = true; 235 adc_feature->ovwren = true; 236 237 adc_feature->res_mode = 12; 238 adc_feature->sample_rate = 1; 239 240 adc_feature->conv_mode = VF610_ADC_CONV_LOW_POWER; 241 242 vf610_adc_calculate_rates(info); 243 } 244 245 static void vf610_adc_cfg_post_set(struct vf610_adc *info) 246 { 247 struct vf610_adc_feature *adc_feature = &info->adc_feature; 248 int cfg_data = 0; 249 int gc_data = 0; 250 251 switch (adc_feature->clk_sel) { 252 case VF610_ADCIOC_ALTCLK_SET: 253 cfg_data |= VF610_ADC_ALTCLK_SEL; 254 break; 255 case VF610_ADCIOC_ADACK_SET: 256 cfg_data |= VF610_ADC_ADACK_SEL; 257 break; 258 default: 259 break; 260 } 261 262 /* low power set for calibration */ 263 cfg_data |= VF610_ADC_ADLPC_EN; 264 265 /* enable high speed for calibration */ 266 cfg_data |= VF610_ADC_ADHSC_EN; 267 268 /* voltage reference */ 269 switch (adc_feature->vol_ref) { 270 case VF610_ADCIOC_VR_VREF_SET: 271 break; 272 case VF610_ADCIOC_VR_VALT_SET: 273 cfg_data |= VF610_ADC_REFSEL_VALT; 274 break; 275 case VF610_ADCIOC_VR_VBG_SET: 276 cfg_data |= VF610_ADC_REFSEL_VBG; 277 break; 278 default: 279 dev_err(info->dev, "error voltage reference\n"); 280 } 281 282 /* data overwrite enable */ 283 if (adc_feature->ovwren) 284 cfg_data |= VF610_ADC_OVWREN; 285 286 writel(cfg_data, info->regs + VF610_REG_ADC_CFG); 287 writel(gc_data, info->regs + VF610_REG_ADC_GC); 288 } 289 290 static void vf610_adc_calibration(struct vf610_adc *info) 291 { 292 int adc_gc, hc_cfg; 293 294 if (!info->adc_feature.calibration) 295 return; 296 297 /* enable calibration interrupt */ 298 hc_cfg = VF610_ADC_AIEN | VF610_ADC_CONV_DISABLE; 299 writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); 300 301 adc_gc = readl(info->regs + VF610_REG_ADC_GC); 302 writel(adc_gc | VF610_ADC_CAL, info->regs + VF610_REG_ADC_GC); 303 304 if (!wait_for_completion_timeout(&info->completion, VF610_ADC_TIMEOUT)) 305 dev_err(info->dev, "Timeout for adc calibration\n"); 306 307 adc_gc = readl(info->regs + VF610_REG_ADC_GS); 308 if (adc_gc & VF610_ADC_CALF) 309 dev_err(info->dev, "ADC calibration failed\n"); 310 311 info->adc_feature.calibration = false; 312 } 313 314 static void vf610_adc_cfg_set(struct vf610_adc *info) 315 { 316 struct vf610_adc_feature *adc_feature = &(info->adc_feature); 317 int cfg_data; 318 319 cfg_data = readl(info->regs + VF610_REG_ADC_CFG); 320 321 cfg_data &= ~VF610_ADC_ADLPC_EN; 322 if (adc_feature->conv_mode == VF610_ADC_CONV_LOW_POWER) 323 cfg_data |= VF610_ADC_ADLPC_EN; 324 325 cfg_data &= ~VF610_ADC_ADHSC_EN; 326 if (adc_feature->conv_mode == VF610_ADC_CONV_HIGH_SPEED) 327 cfg_data |= VF610_ADC_ADHSC_EN; 328 329 writel(cfg_data, info->regs + VF610_REG_ADC_CFG); 330 } 331 332 static void vf610_adc_sample_set(struct vf610_adc *info) 333 { 334 struct vf610_adc_feature *adc_feature = &(info->adc_feature); 335 int cfg_data, gc_data; 336 337 cfg_data = readl(info->regs + VF610_REG_ADC_CFG); 338 gc_data = readl(info->regs + VF610_REG_ADC_GC); 339 340 /* resolution mode */ 341 cfg_data &= ~VF610_ADC_MODE_MASK; 342 switch (adc_feature->res_mode) { 343 case 8: 344 cfg_data |= VF610_ADC_MODE_BIT8; 345 break; 346 case 10: 347 cfg_data |= VF610_ADC_MODE_BIT10; 348 break; 349 case 12: 350 cfg_data |= VF610_ADC_MODE_BIT12; 351 break; 352 default: 353 dev_err(info->dev, "error resolution mode\n"); 354 break; 355 } 356 357 /* clock select and clock divider */ 358 cfg_data &= ~(VF610_ADC_CLK_MASK | VF610_ADC_ADCCLK_MASK); 359 switch (adc_feature->clk_div) { 360 case 1: 361 break; 362 case 2: 363 cfg_data |= VF610_ADC_CLK_DIV2; 364 break; 365 case 4: 366 cfg_data |= VF610_ADC_CLK_DIV4; 367 break; 368 case 8: 369 cfg_data |= VF610_ADC_CLK_DIV8; 370 break; 371 case 16: 372 switch (adc_feature->clk_sel) { 373 case VF610_ADCIOC_BUSCLK_SET: 374 cfg_data |= VF610_ADC_BUSCLK2_SEL | VF610_ADC_CLK_DIV8; 375 break; 376 default: 377 dev_err(info->dev, "error clk divider\n"); 378 break; 379 } 380 break; 381 } 382 383 /* 384 * Set ADLSMP and ADSTS based on the Long Sample Time Adder value 385 * determined. 386 */ 387 switch (adc_feature->lst_adder_index) { 388 case VF610_ADCK_CYCLES_3: 389 break; 390 case VF610_ADCK_CYCLES_5: 391 cfg_data |= VF610_ADC_ADSTS_SHORT; 392 break; 393 case VF610_ADCK_CYCLES_7: 394 cfg_data |= VF610_ADC_ADSTS_NORMAL; 395 break; 396 case VF610_ADCK_CYCLES_9: 397 cfg_data |= VF610_ADC_ADSTS_LONG; 398 break; 399 case VF610_ADCK_CYCLES_13: 400 cfg_data |= VF610_ADC_ADLSMP_LONG; 401 break; 402 case VF610_ADCK_CYCLES_17: 403 cfg_data |= VF610_ADC_ADLSMP_LONG; 404 cfg_data |= VF610_ADC_ADSTS_SHORT; 405 break; 406 case VF610_ADCK_CYCLES_21: 407 cfg_data |= VF610_ADC_ADLSMP_LONG; 408 cfg_data |= VF610_ADC_ADSTS_NORMAL; 409 break; 410 case VF610_ADCK_CYCLES_25: 411 cfg_data |= VF610_ADC_ADLSMP_LONG; 412 cfg_data |= VF610_ADC_ADSTS_NORMAL; 413 break; 414 default: 415 dev_err(info->dev, "error in sample time select\n"); 416 } 417 418 /* update hardware average selection */ 419 cfg_data &= ~VF610_ADC_AVGS_MASK; 420 gc_data &= ~VF610_ADC_AVGEN; 421 switch (adc_feature->sample_rate) { 422 case VF610_ADC_SAMPLE_1: 423 break; 424 case VF610_ADC_SAMPLE_4: 425 gc_data |= VF610_ADC_AVGEN; 426 break; 427 case VF610_ADC_SAMPLE_8: 428 gc_data |= VF610_ADC_AVGEN; 429 cfg_data |= VF610_ADC_AVGS_8; 430 break; 431 case VF610_ADC_SAMPLE_16: 432 gc_data |= VF610_ADC_AVGEN; 433 cfg_data |= VF610_ADC_AVGS_16; 434 break; 435 case VF610_ADC_SAMPLE_32: 436 gc_data |= VF610_ADC_AVGEN; 437 cfg_data |= VF610_ADC_AVGS_32; 438 break; 439 default: 440 dev_err(info->dev, 441 "error hardware sample average select\n"); 442 } 443 444 writel(cfg_data, info->regs + VF610_REG_ADC_CFG); 445 writel(gc_data, info->regs + VF610_REG_ADC_GC); 446 } 447 448 static void vf610_adc_hw_init(struct vf610_adc *info) 449 { 450 /* CFG: Feature set */ 451 vf610_adc_cfg_post_set(info); 452 vf610_adc_sample_set(info); 453 454 /* adc calibration */ 455 vf610_adc_calibration(info); 456 457 /* CFG: power and speed set */ 458 vf610_adc_cfg_set(info); 459 } 460 461 static int vf610_set_conversion_mode(struct iio_dev *indio_dev, 462 const struct iio_chan_spec *chan, 463 unsigned int mode) 464 { 465 struct vf610_adc *info = iio_priv(indio_dev); 466 467 mutex_lock(&indio_dev->mlock); 468 info->adc_feature.conv_mode = mode; 469 vf610_adc_calculate_rates(info); 470 vf610_adc_hw_init(info); 471 mutex_unlock(&indio_dev->mlock); 472 473 return 0; 474 } 475 476 static int vf610_get_conversion_mode(struct iio_dev *indio_dev, 477 const struct iio_chan_spec *chan) 478 { 479 struct vf610_adc *info = iio_priv(indio_dev); 480 481 return info->adc_feature.conv_mode; 482 } 483 484 static const char * const vf610_conv_modes[] = { "normal", "high-speed", 485 "low-power" }; 486 487 static const struct iio_enum vf610_conversion_mode = { 488 .items = vf610_conv_modes, 489 .num_items = ARRAY_SIZE(vf610_conv_modes), 490 .get = vf610_get_conversion_mode, 491 .set = vf610_set_conversion_mode, 492 }; 493 494 static const struct iio_chan_spec_ext_info vf610_ext_info[] = { 495 IIO_ENUM("conversion_mode", IIO_SHARED_BY_DIR, &vf610_conversion_mode), 496 {}, 497 }; 498 499 #define VF610_ADC_CHAN(_idx, _chan_type) { \ 500 .type = (_chan_type), \ 501 .indexed = 1, \ 502 .channel = (_idx), \ 503 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 504 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ 505 BIT(IIO_CHAN_INFO_SAMP_FREQ), \ 506 .ext_info = vf610_ext_info, \ 507 .scan_index = (_idx), \ 508 .scan_type = { \ 509 .sign = 'u', \ 510 .realbits = 12, \ 511 .storagebits = 16, \ 512 }, \ 513 } 514 515 #define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) { \ 516 .type = (_chan_type), \ 517 .channel = (_idx), \ 518 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \ 519 .scan_index = (_idx), \ 520 .scan_type = { \ 521 .sign = 'u', \ 522 .realbits = 12, \ 523 .storagebits = 16, \ 524 }, \ 525 } 526 527 static const struct iio_chan_spec vf610_adc_iio_channels[] = { 528 VF610_ADC_CHAN(0, IIO_VOLTAGE), 529 VF610_ADC_CHAN(1, IIO_VOLTAGE), 530 VF610_ADC_CHAN(2, IIO_VOLTAGE), 531 VF610_ADC_CHAN(3, IIO_VOLTAGE), 532 VF610_ADC_CHAN(4, IIO_VOLTAGE), 533 VF610_ADC_CHAN(5, IIO_VOLTAGE), 534 VF610_ADC_CHAN(6, IIO_VOLTAGE), 535 VF610_ADC_CHAN(7, IIO_VOLTAGE), 536 VF610_ADC_CHAN(8, IIO_VOLTAGE), 537 VF610_ADC_CHAN(9, IIO_VOLTAGE), 538 VF610_ADC_CHAN(10, IIO_VOLTAGE), 539 VF610_ADC_CHAN(11, IIO_VOLTAGE), 540 VF610_ADC_CHAN(12, IIO_VOLTAGE), 541 VF610_ADC_CHAN(13, IIO_VOLTAGE), 542 VF610_ADC_CHAN(14, IIO_VOLTAGE), 543 VF610_ADC_CHAN(15, IIO_VOLTAGE), 544 VF610_ADC_TEMPERATURE_CHAN(26, IIO_TEMP), 545 IIO_CHAN_SOFT_TIMESTAMP(32), 546 /* sentinel */ 547 }; 548 549 static int vf610_adc_read_data(struct vf610_adc *info) 550 { 551 int result; 552 553 result = readl(info->regs + VF610_REG_ADC_R0); 554 555 switch (info->adc_feature.res_mode) { 556 case 8: 557 result &= 0xFF; 558 break; 559 case 10: 560 result &= 0x3FF; 561 break; 562 case 12: 563 result &= 0xFFF; 564 break; 565 default: 566 break; 567 } 568 569 return result; 570 } 571 572 static irqreturn_t vf610_adc_isr(int irq, void *dev_id) 573 { 574 struct iio_dev *indio_dev = dev_id; 575 struct vf610_adc *info = iio_priv(indio_dev); 576 int coco; 577 578 coco = readl(info->regs + VF610_REG_ADC_HS); 579 if (coco & VF610_ADC_HS_COCO0) { 580 info->value = vf610_adc_read_data(info); 581 if (iio_buffer_enabled(indio_dev)) { 582 info->buffer[0] = info->value; 583 iio_push_to_buffers_with_timestamp(indio_dev, 584 info->buffer, 585 iio_get_time_ns(indio_dev)); 586 iio_trigger_notify_done(indio_dev->trig); 587 } else 588 complete(&info->completion); 589 } 590 591 return IRQ_HANDLED; 592 } 593 594 static ssize_t vf610_show_samp_freq_avail(struct device *dev, 595 struct device_attribute *attr, char *buf) 596 { 597 struct vf610_adc *info = iio_priv(dev_to_iio_dev(dev)); 598 size_t len = 0; 599 int i; 600 601 for (i = 0; i < ARRAY_SIZE(info->sample_freq_avail); i++) 602 len += scnprintf(buf + len, PAGE_SIZE - len, 603 "%u ", info->sample_freq_avail[i]); 604 605 /* replace trailing space by newline */ 606 buf[len - 1] = '\n'; 607 608 return len; 609 } 610 611 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(vf610_show_samp_freq_avail); 612 613 static struct attribute *vf610_attributes[] = { 614 &iio_dev_attr_sampling_frequency_available.dev_attr.attr, 615 NULL 616 }; 617 618 static const struct attribute_group vf610_attribute_group = { 619 .attrs = vf610_attributes, 620 }; 621 622 static int vf610_read_raw(struct iio_dev *indio_dev, 623 struct iio_chan_spec const *chan, 624 int *val, 625 int *val2, 626 long mask) 627 { 628 struct vf610_adc *info = iio_priv(indio_dev); 629 unsigned int hc_cfg; 630 long ret; 631 632 switch (mask) { 633 case IIO_CHAN_INFO_RAW: 634 case IIO_CHAN_INFO_PROCESSED: 635 mutex_lock(&indio_dev->mlock); 636 if (iio_buffer_enabled(indio_dev)) { 637 mutex_unlock(&indio_dev->mlock); 638 return -EBUSY; 639 } 640 641 reinit_completion(&info->completion); 642 hc_cfg = VF610_ADC_ADCHC(chan->channel); 643 hc_cfg |= VF610_ADC_AIEN; 644 writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); 645 ret = wait_for_completion_interruptible_timeout 646 (&info->completion, VF610_ADC_TIMEOUT); 647 if (ret == 0) { 648 mutex_unlock(&indio_dev->mlock); 649 return -ETIMEDOUT; 650 } 651 if (ret < 0) { 652 mutex_unlock(&indio_dev->mlock); 653 return ret; 654 } 655 656 switch (chan->type) { 657 case IIO_VOLTAGE: 658 *val = info->value; 659 break; 660 case IIO_TEMP: 661 /* 662 * Calculate in degree Celsius times 1000 663 * Using the typical sensor slope of 1.84 mV/°C 664 * and VREFH_ADC at 3.3V, V at 25°C of 699 mV 665 */ 666 *val = 25000 - ((int)info->value - VF610_VTEMP25_3V3) * 667 1000000 / VF610_TEMP_SLOPE_COEFF; 668 669 break; 670 default: 671 mutex_unlock(&indio_dev->mlock); 672 return -EINVAL; 673 } 674 675 mutex_unlock(&indio_dev->mlock); 676 return IIO_VAL_INT; 677 678 case IIO_CHAN_INFO_SCALE: 679 *val = info->vref_uv / 1000; 680 *val2 = info->adc_feature.res_mode; 681 return IIO_VAL_FRACTIONAL_LOG2; 682 683 case IIO_CHAN_INFO_SAMP_FREQ: 684 *val = info->sample_freq_avail[info->adc_feature.sample_rate]; 685 *val2 = 0; 686 return IIO_VAL_INT; 687 688 default: 689 break; 690 } 691 692 return -EINVAL; 693 } 694 695 static int vf610_write_raw(struct iio_dev *indio_dev, 696 struct iio_chan_spec const *chan, 697 int val, 698 int val2, 699 long mask) 700 { 701 struct vf610_adc *info = iio_priv(indio_dev); 702 int i; 703 704 switch (mask) { 705 case IIO_CHAN_INFO_SAMP_FREQ: 706 for (i = 0; 707 i < ARRAY_SIZE(info->sample_freq_avail); 708 i++) 709 if (val == info->sample_freq_avail[i]) { 710 info->adc_feature.sample_rate = i; 711 vf610_adc_sample_set(info); 712 return 0; 713 } 714 break; 715 716 default: 717 break; 718 } 719 720 return -EINVAL; 721 } 722 723 static int vf610_adc_buffer_postenable(struct iio_dev *indio_dev) 724 { 725 struct vf610_adc *info = iio_priv(indio_dev); 726 unsigned int channel; 727 int val; 728 729 val = readl(info->regs + VF610_REG_ADC_GC); 730 val |= VF610_ADC_ADCON; 731 writel(val, info->regs + VF610_REG_ADC_GC); 732 733 channel = find_first_bit(indio_dev->active_scan_mask, 734 indio_dev->masklength); 735 736 val = VF610_ADC_ADCHC(channel); 737 val |= VF610_ADC_AIEN; 738 739 writel(val, info->regs + VF610_REG_ADC_HC0); 740 741 return 0; 742 } 743 744 static int vf610_adc_buffer_predisable(struct iio_dev *indio_dev) 745 { 746 struct vf610_adc *info = iio_priv(indio_dev); 747 unsigned int hc_cfg = 0; 748 int val; 749 750 val = readl(info->regs + VF610_REG_ADC_GC); 751 val &= ~VF610_ADC_ADCON; 752 writel(val, info->regs + VF610_REG_ADC_GC); 753 754 hc_cfg |= VF610_ADC_CONV_DISABLE; 755 hc_cfg &= ~VF610_ADC_AIEN; 756 757 writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); 758 759 return 0; 760 } 761 762 static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = { 763 .postenable = &vf610_adc_buffer_postenable, 764 .predisable = &vf610_adc_buffer_predisable, 765 .validate_scan_mask = &iio_validate_scan_mask_onehot, 766 }; 767 768 static int vf610_adc_reg_access(struct iio_dev *indio_dev, 769 unsigned reg, unsigned writeval, 770 unsigned *readval) 771 { 772 struct vf610_adc *info = iio_priv(indio_dev); 773 774 if ((readval == NULL) || 775 ((reg % 4) || (reg > VF610_REG_ADC_PCTL))) 776 return -EINVAL; 777 778 *readval = readl(info->regs + reg); 779 780 return 0; 781 } 782 783 static const struct iio_info vf610_adc_iio_info = { 784 .read_raw = &vf610_read_raw, 785 .write_raw = &vf610_write_raw, 786 .debugfs_reg_access = &vf610_adc_reg_access, 787 .attrs = &vf610_attribute_group, 788 }; 789 790 static const struct of_device_id vf610_adc_match[] = { 791 { .compatible = "fsl,vf610-adc", }, 792 { /* sentinel */ } 793 }; 794 MODULE_DEVICE_TABLE(of, vf610_adc_match); 795 796 static int vf610_adc_probe(struct platform_device *pdev) 797 { 798 struct vf610_adc *info; 799 struct iio_dev *indio_dev; 800 int irq; 801 int ret; 802 803 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct vf610_adc)); 804 if (!indio_dev) { 805 dev_err(&pdev->dev, "Failed allocating iio device\n"); 806 return -ENOMEM; 807 } 808 809 info = iio_priv(indio_dev); 810 info->dev = &pdev->dev; 811 812 info->regs = devm_platform_ioremap_resource(pdev, 0); 813 if (IS_ERR(info->regs)) 814 return PTR_ERR(info->regs); 815 816 irq = platform_get_irq(pdev, 0); 817 if (irq < 0) 818 return irq; 819 820 ret = devm_request_irq(info->dev, irq, 821 vf610_adc_isr, 0, 822 dev_name(&pdev->dev), indio_dev); 823 if (ret < 0) { 824 dev_err(&pdev->dev, "failed requesting irq, irq = %d\n", irq); 825 return ret; 826 } 827 828 info->clk = devm_clk_get(&pdev->dev, "adc"); 829 if (IS_ERR(info->clk)) { 830 dev_err(&pdev->dev, "failed getting clock, err = %ld\n", 831 PTR_ERR(info->clk)); 832 return PTR_ERR(info->clk); 833 } 834 835 info->vref = devm_regulator_get(&pdev->dev, "vref"); 836 if (IS_ERR(info->vref)) 837 return PTR_ERR(info->vref); 838 839 ret = regulator_enable(info->vref); 840 if (ret) 841 return ret; 842 843 info->vref_uv = regulator_get_voltage(info->vref); 844 845 of_property_read_u32_array(pdev->dev.of_node, "fsl,adck-max-frequency", 846 info->max_adck_rate, 3); 847 848 ret = of_property_read_u32(pdev->dev.of_node, "min-sample-time", 849 &info->adc_feature.default_sample_time); 850 if (ret) 851 info->adc_feature.default_sample_time = DEFAULT_SAMPLE_TIME; 852 853 platform_set_drvdata(pdev, indio_dev); 854 855 init_completion(&info->completion); 856 857 indio_dev->name = dev_name(&pdev->dev); 858 indio_dev->info = &vf610_adc_iio_info; 859 indio_dev->modes = INDIO_DIRECT_MODE; 860 indio_dev->channels = vf610_adc_iio_channels; 861 indio_dev->num_channels = ARRAY_SIZE(vf610_adc_iio_channels); 862 863 ret = clk_prepare_enable(info->clk); 864 if (ret) { 865 dev_err(&pdev->dev, 866 "Could not prepare or enable the clock.\n"); 867 goto error_adc_clk_enable; 868 } 869 870 vf610_adc_cfg_init(info); 871 vf610_adc_hw_init(info); 872 873 ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, 874 NULL, &iio_triggered_buffer_setup_ops); 875 if (ret < 0) { 876 dev_err(&pdev->dev, "Couldn't initialise the buffer\n"); 877 goto error_iio_device_register; 878 } 879 880 ret = iio_device_register(indio_dev); 881 if (ret) { 882 dev_err(&pdev->dev, "Couldn't register the device.\n"); 883 goto error_adc_buffer_init; 884 } 885 886 return 0; 887 888 error_adc_buffer_init: 889 iio_triggered_buffer_cleanup(indio_dev); 890 error_iio_device_register: 891 clk_disable_unprepare(info->clk); 892 error_adc_clk_enable: 893 regulator_disable(info->vref); 894 895 return ret; 896 } 897 898 static int vf610_adc_remove(struct platform_device *pdev) 899 { 900 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 901 struct vf610_adc *info = iio_priv(indio_dev); 902 903 iio_device_unregister(indio_dev); 904 iio_triggered_buffer_cleanup(indio_dev); 905 regulator_disable(info->vref); 906 clk_disable_unprepare(info->clk); 907 908 return 0; 909 } 910 911 #ifdef CONFIG_PM_SLEEP 912 static int vf610_adc_suspend(struct device *dev) 913 { 914 struct iio_dev *indio_dev = dev_get_drvdata(dev); 915 struct vf610_adc *info = iio_priv(indio_dev); 916 int hc_cfg; 917 918 /* ADC controller enters to stop mode */ 919 hc_cfg = readl(info->regs + VF610_REG_ADC_HC0); 920 hc_cfg |= VF610_ADC_CONV_DISABLE; 921 writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); 922 923 clk_disable_unprepare(info->clk); 924 regulator_disable(info->vref); 925 926 return 0; 927 } 928 929 static int vf610_adc_resume(struct device *dev) 930 { 931 struct iio_dev *indio_dev = dev_get_drvdata(dev); 932 struct vf610_adc *info = iio_priv(indio_dev); 933 int ret; 934 935 ret = regulator_enable(info->vref); 936 if (ret) 937 return ret; 938 939 ret = clk_prepare_enable(info->clk); 940 if (ret) 941 goto disable_reg; 942 943 vf610_adc_hw_init(info); 944 945 return 0; 946 947 disable_reg: 948 regulator_disable(info->vref); 949 return ret; 950 } 951 #endif 952 953 static SIMPLE_DEV_PM_OPS(vf610_adc_pm_ops, vf610_adc_suspend, vf610_adc_resume); 954 955 static struct platform_driver vf610_adc_driver = { 956 .probe = vf610_adc_probe, 957 .remove = vf610_adc_remove, 958 .driver = { 959 .name = DRIVER_NAME, 960 .of_match_table = vf610_adc_match, 961 .pm = &vf610_adc_pm_ops, 962 }, 963 }; 964 965 module_platform_driver(vf610_adc_driver); 966 967 MODULE_AUTHOR("Fugang Duan <B38611@freescale.com>"); 968 MODULE_DESCRIPTION("Freescale VF610 ADC driver"); 969 MODULE_LICENSE("GPL v2"); 970