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 /* Ensure the timestamp is naturally aligned */ 171 struct { 172 u16 chan; 173 s64 timestamp __aligned(8); 174 } scan; 175 }; 176 177 static const u32 vf610_hw_avgs[] = { 1, 4, 8, 16, 32 }; 178 static const u32 vf610_lst_adder[] = { 3, 5, 7, 9, 13, 17, 21, 25 }; 179 180 static inline void vf610_adc_calculate_rates(struct vf610_adc *info) 181 { 182 struct vf610_adc_feature *adc_feature = &info->adc_feature; 183 unsigned long adck_rate, ipg_rate = clk_get_rate(info->clk); 184 u32 adck_period, lst_addr_min; 185 int divisor, i; 186 187 adck_rate = info->max_adck_rate[adc_feature->conv_mode]; 188 189 if (adck_rate) { 190 /* calculate clk divider which is within specification */ 191 divisor = ipg_rate / adck_rate; 192 adc_feature->clk_div = 1 << fls(divisor + 1); 193 } else { 194 /* fall-back value using a safe divisor */ 195 adc_feature->clk_div = 8; 196 } 197 198 adck_rate = ipg_rate / adc_feature->clk_div; 199 200 /* 201 * Determine the long sample time adder value to be used based 202 * on the default minimum sample time provided. 203 */ 204 adck_period = NSEC_PER_SEC / adck_rate; 205 lst_addr_min = adc_feature->default_sample_time / adck_period; 206 for (i = 0; i < ARRAY_SIZE(vf610_lst_adder); i++) { 207 if (vf610_lst_adder[i] > lst_addr_min) { 208 adc_feature->lst_adder_index = i; 209 break; 210 } 211 } 212 213 /* 214 * Calculate ADC sample frequencies 215 * Sample time unit is ADCK cycles. ADCK clk source is ipg clock, 216 * which is the same as bus clock. 217 * 218 * ADC conversion time = SFCAdder + AverageNum x (BCT + LSTAdder) 219 * SFCAdder: fixed to 6 ADCK cycles 220 * AverageNum: 1, 4, 8, 16, 32 samples for hardware average. 221 * BCT (Base Conversion Time): fixed to 25 ADCK cycles for 12 bit mode 222 * LSTAdder(Long Sample Time): 3, 5, 7, 9, 13, 17, 21, 25 ADCK cycles 223 */ 224 for (i = 0; i < ARRAY_SIZE(vf610_hw_avgs); i++) 225 info->sample_freq_avail[i] = 226 adck_rate / (6 + vf610_hw_avgs[i] * 227 (25 + vf610_lst_adder[adc_feature->lst_adder_index])); 228 } 229 230 static inline void vf610_adc_cfg_init(struct vf610_adc *info) 231 { 232 struct vf610_adc_feature *adc_feature = &info->adc_feature; 233 234 /* set default Configuration for ADC controller */ 235 adc_feature->clk_sel = VF610_ADCIOC_BUSCLK_SET; 236 adc_feature->vol_ref = VF610_ADCIOC_VR_VREF_SET; 237 238 adc_feature->calibration = true; 239 adc_feature->ovwren = true; 240 241 adc_feature->res_mode = 12; 242 adc_feature->sample_rate = 1; 243 244 adc_feature->conv_mode = VF610_ADC_CONV_LOW_POWER; 245 246 vf610_adc_calculate_rates(info); 247 } 248 249 static void vf610_adc_cfg_post_set(struct vf610_adc *info) 250 { 251 struct vf610_adc_feature *adc_feature = &info->adc_feature; 252 int cfg_data = 0; 253 int gc_data = 0; 254 255 switch (adc_feature->clk_sel) { 256 case VF610_ADCIOC_ALTCLK_SET: 257 cfg_data |= VF610_ADC_ALTCLK_SEL; 258 break; 259 case VF610_ADCIOC_ADACK_SET: 260 cfg_data |= VF610_ADC_ADACK_SEL; 261 break; 262 default: 263 break; 264 } 265 266 /* low power set for calibration */ 267 cfg_data |= VF610_ADC_ADLPC_EN; 268 269 /* enable high speed for calibration */ 270 cfg_data |= VF610_ADC_ADHSC_EN; 271 272 /* voltage reference */ 273 switch (adc_feature->vol_ref) { 274 case VF610_ADCIOC_VR_VREF_SET: 275 break; 276 case VF610_ADCIOC_VR_VALT_SET: 277 cfg_data |= VF610_ADC_REFSEL_VALT; 278 break; 279 case VF610_ADCIOC_VR_VBG_SET: 280 cfg_data |= VF610_ADC_REFSEL_VBG; 281 break; 282 default: 283 dev_err(info->dev, "error voltage reference\n"); 284 } 285 286 /* data overwrite enable */ 287 if (adc_feature->ovwren) 288 cfg_data |= VF610_ADC_OVWREN; 289 290 writel(cfg_data, info->regs + VF610_REG_ADC_CFG); 291 writel(gc_data, info->regs + VF610_REG_ADC_GC); 292 } 293 294 static void vf610_adc_calibration(struct vf610_adc *info) 295 { 296 int adc_gc, hc_cfg; 297 298 if (!info->adc_feature.calibration) 299 return; 300 301 /* enable calibration interrupt */ 302 hc_cfg = VF610_ADC_AIEN | VF610_ADC_CONV_DISABLE; 303 writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); 304 305 adc_gc = readl(info->regs + VF610_REG_ADC_GC); 306 writel(adc_gc | VF610_ADC_CAL, info->regs + VF610_REG_ADC_GC); 307 308 if (!wait_for_completion_timeout(&info->completion, VF610_ADC_TIMEOUT)) 309 dev_err(info->dev, "Timeout for adc calibration\n"); 310 311 adc_gc = readl(info->regs + VF610_REG_ADC_GS); 312 if (adc_gc & VF610_ADC_CALF) 313 dev_err(info->dev, "ADC calibration failed\n"); 314 315 info->adc_feature.calibration = false; 316 } 317 318 static void vf610_adc_cfg_set(struct vf610_adc *info) 319 { 320 struct vf610_adc_feature *adc_feature = &(info->adc_feature); 321 int cfg_data; 322 323 cfg_data = readl(info->regs + VF610_REG_ADC_CFG); 324 325 cfg_data &= ~VF610_ADC_ADLPC_EN; 326 if (adc_feature->conv_mode == VF610_ADC_CONV_LOW_POWER) 327 cfg_data |= VF610_ADC_ADLPC_EN; 328 329 cfg_data &= ~VF610_ADC_ADHSC_EN; 330 if (adc_feature->conv_mode == VF610_ADC_CONV_HIGH_SPEED) 331 cfg_data |= VF610_ADC_ADHSC_EN; 332 333 writel(cfg_data, info->regs + VF610_REG_ADC_CFG); 334 } 335 336 static void vf610_adc_sample_set(struct vf610_adc *info) 337 { 338 struct vf610_adc_feature *adc_feature = &(info->adc_feature); 339 int cfg_data, gc_data; 340 341 cfg_data = readl(info->regs + VF610_REG_ADC_CFG); 342 gc_data = readl(info->regs + VF610_REG_ADC_GC); 343 344 /* resolution mode */ 345 cfg_data &= ~VF610_ADC_MODE_MASK; 346 switch (adc_feature->res_mode) { 347 case 8: 348 cfg_data |= VF610_ADC_MODE_BIT8; 349 break; 350 case 10: 351 cfg_data |= VF610_ADC_MODE_BIT10; 352 break; 353 case 12: 354 cfg_data |= VF610_ADC_MODE_BIT12; 355 break; 356 default: 357 dev_err(info->dev, "error resolution mode\n"); 358 break; 359 } 360 361 /* clock select and clock divider */ 362 cfg_data &= ~(VF610_ADC_CLK_MASK | VF610_ADC_ADCCLK_MASK); 363 switch (adc_feature->clk_div) { 364 case 1: 365 break; 366 case 2: 367 cfg_data |= VF610_ADC_CLK_DIV2; 368 break; 369 case 4: 370 cfg_data |= VF610_ADC_CLK_DIV4; 371 break; 372 case 8: 373 cfg_data |= VF610_ADC_CLK_DIV8; 374 break; 375 case 16: 376 switch (adc_feature->clk_sel) { 377 case VF610_ADCIOC_BUSCLK_SET: 378 cfg_data |= VF610_ADC_BUSCLK2_SEL | VF610_ADC_CLK_DIV8; 379 break; 380 default: 381 dev_err(info->dev, "error clk divider\n"); 382 break; 383 } 384 break; 385 } 386 387 /* 388 * Set ADLSMP and ADSTS based on the Long Sample Time Adder value 389 * determined. 390 */ 391 switch (adc_feature->lst_adder_index) { 392 case VF610_ADCK_CYCLES_3: 393 break; 394 case VF610_ADCK_CYCLES_5: 395 cfg_data |= VF610_ADC_ADSTS_SHORT; 396 break; 397 case VF610_ADCK_CYCLES_7: 398 cfg_data |= VF610_ADC_ADSTS_NORMAL; 399 break; 400 case VF610_ADCK_CYCLES_9: 401 cfg_data |= VF610_ADC_ADSTS_LONG; 402 break; 403 case VF610_ADCK_CYCLES_13: 404 cfg_data |= VF610_ADC_ADLSMP_LONG; 405 break; 406 case VF610_ADCK_CYCLES_17: 407 cfg_data |= VF610_ADC_ADLSMP_LONG; 408 cfg_data |= VF610_ADC_ADSTS_SHORT; 409 break; 410 case VF610_ADCK_CYCLES_21: 411 cfg_data |= VF610_ADC_ADLSMP_LONG; 412 cfg_data |= VF610_ADC_ADSTS_NORMAL; 413 break; 414 case VF610_ADCK_CYCLES_25: 415 cfg_data |= VF610_ADC_ADLSMP_LONG; 416 cfg_data |= VF610_ADC_ADSTS_NORMAL; 417 break; 418 default: 419 dev_err(info->dev, "error in sample time select\n"); 420 } 421 422 /* update hardware average selection */ 423 cfg_data &= ~VF610_ADC_AVGS_MASK; 424 gc_data &= ~VF610_ADC_AVGEN; 425 switch (adc_feature->sample_rate) { 426 case VF610_ADC_SAMPLE_1: 427 break; 428 case VF610_ADC_SAMPLE_4: 429 gc_data |= VF610_ADC_AVGEN; 430 break; 431 case VF610_ADC_SAMPLE_8: 432 gc_data |= VF610_ADC_AVGEN; 433 cfg_data |= VF610_ADC_AVGS_8; 434 break; 435 case VF610_ADC_SAMPLE_16: 436 gc_data |= VF610_ADC_AVGEN; 437 cfg_data |= VF610_ADC_AVGS_16; 438 break; 439 case VF610_ADC_SAMPLE_32: 440 gc_data |= VF610_ADC_AVGEN; 441 cfg_data |= VF610_ADC_AVGS_32; 442 break; 443 default: 444 dev_err(info->dev, 445 "error hardware sample average select\n"); 446 } 447 448 writel(cfg_data, info->regs + VF610_REG_ADC_CFG); 449 writel(gc_data, info->regs + VF610_REG_ADC_GC); 450 } 451 452 static void vf610_adc_hw_init(struct vf610_adc *info) 453 { 454 /* CFG: Feature set */ 455 vf610_adc_cfg_post_set(info); 456 vf610_adc_sample_set(info); 457 458 /* adc calibration */ 459 vf610_adc_calibration(info); 460 461 /* CFG: power and speed set */ 462 vf610_adc_cfg_set(info); 463 } 464 465 static int vf610_set_conversion_mode(struct iio_dev *indio_dev, 466 const struct iio_chan_spec *chan, 467 unsigned int mode) 468 { 469 struct vf610_adc *info = iio_priv(indio_dev); 470 471 mutex_lock(&indio_dev->mlock); 472 info->adc_feature.conv_mode = mode; 473 vf610_adc_calculate_rates(info); 474 vf610_adc_hw_init(info); 475 mutex_unlock(&indio_dev->mlock); 476 477 return 0; 478 } 479 480 static int vf610_get_conversion_mode(struct iio_dev *indio_dev, 481 const struct iio_chan_spec *chan) 482 { 483 struct vf610_adc *info = iio_priv(indio_dev); 484 485 return info->adc_feature.conv_mode; 486 } 487 488 static const char * const vf610_conv_modes[] = { "normal", "high-speed", 489 "low-power" }; 490 491 static const struct iio_enum vf610_conversion_mode = { 492 .items = vf610_conv_modes, 493 .num_items = ARRAY_SIZE(vf610_conv_modes), 494 .get = vf610_get_conversion_mode, 495 .set = vf610_set_conversion_mode, 496 }; 497 498 static const struct iio_chan_spec_ext_info vf610_ext_info[] = { 499 IIO_ENUM("conversion_mode", IIO_SHARED_BY_DIR, &vf610_conversion_mode), 500 {}, 501 }; 502 503 #define VF610_ADC_CHAN(_idx, _chan_type) { \ 504 .type = (_chan_type), \ 505 .indexed = 1, \ 506 .channel = (_idx), \ 507 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 508 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ 509 BIT(IIO_CHAN_INFO_SAMP_FREQ), \ 510 .ext_info = vf610_ext_info, \ 511 .scan_index = (_idx), \ 512 .scan_type = { \ 513 .sign = 'u', \ 514 .realbits = 12, \ 515 .storagebits = 16, \ 516 }, \ 517 } 518 519 #define VF610_ADC_TEMPERATURE_CHAN(_idx, _chan_type) { \ 520 .type = (_chan_type), \ 521 .channel = (_idx), \ 522 .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \ 523 .scan_index = (_idx), \ 524 .scan_type = { \ 525 .sign = 'u', \ 526 .realbits = 12, \ 527 .storagebits = 16, \ 528 }, \ 529 } 530 531 static const struct iio_chan_spec vf610_adc_iio_channels[] = { 532 VF610_ADC_CHAN(0, IIO_VOLTAGE), 533 VF610_ADC_CHAN(1, IIO_VOLTAGE), 534 VF610_ADC_CHAN(2, IIO_VOLTAGE), 535 VF610_ADC_CHAN(3, IIO_VOLTAGE), 536 VF610_ADC_CHAN(4, IIO_VOLTAGE), 537 VF610_ADC_CHAN(5, IIO_VOLTAGE), 538 VF610_ADC_CHAN(6, IIO_VOLTAGE), 539 VF610_ADC_CHAN(7, IIO_VOLTAGE), 540 VF610_ADC_CHAN(8, IIO_VOLTAGE), 541 VF610_ADC_CHAN(9, IIO_VOLTAGE), 542 VF610_ADC_CHAN(10, IIO_VOLTAGE), 543 VF610_ADC_CHAN(11, IIO_VOLTAGE), 544 VF610_ADC_CHAN(12, IIO_VOLTAGE), 545 VF610_ADC_CHAN(13, IIO_VOLTAGE), 546 VF610_ADC_CHAN(14, IIO_VOLTAGE), 547 VF610_ADC_CHAN(15, IIO_VOLTAGE), 548 VF610_ADC_TEMPERATURE_CHAN(26, IIO_TEMP), 549 IIO_CHAN_SOFT_TIMESTAMP(32), 550 /* sentinel */ 551 }; 552 553 static int vf610_adc_read_data(struct vf610_adc *info) 554 { 555 int result; 556 557 result = readl(info->regs + VF610_REG_ADC_R0); 558 559 switch (info->adc_feature.res_mode) { 560 case 8: 561 result &= 0xFF; 562 break; 563 case 10: 564 result &= 0x3FF; 565 break; 566 case 12: 567 result &= 0xFFF; 568 break; 569 default: 570 break; 571 } 572 573 return result; 574 } 575 576 static irqreturn_t vf610_adc_isr(int irq, void *dev_id) 577 { 578 struct iio_dev *indio_dev = dev_id; 579 struct vf610_adc *info = iio_priv(indio_dev); 580 int coco; 581 582 coco = readl(info->regs + VF610_REG_ADC_HS); 583 if (coco & VF610_ADC_HS_COCO0) { 584 info->value = vf610_adc_read_data(info); 585 if (iio_buffer_enabled(indio_dev)) { 586 info->scan.chan = info->value; 587 iio_push_to_buffers_with_timestamp(indio_dev, 588 &info->scan, 589 iio_get_time_ns(indio_dev)); 590 iio_trigger_notify_done(indio_dev->trig); 591 } else 592 complete(&info->completion); 593 } 594 595 return IRQ_HANDLED; 596 } 597 598 static ssize_t vf610_show_samp_freq_avail(struct device *dev, 599 struct device_attribute *attr, char *buf) 600 { 601 struct vf610_adc *info = iio_priv(dev_to_iio_dev(dev)); 602 size_t len = 0; 603 int i; 604 605 for (i = 0; i < ARRAY_SIZE(info->sample_freq_avail); i++) 606 len += scnprintf(buf + len, PAGE_SIZE - len, 607 "%u ", info->sample_freq_avail[i]); 608 609 /* replace trailing space by newline */ 610 buf[len - 1] = '\n'; 611 612 return len; 613 } 614 615 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(vf610_show_samp_freq_avail); 616 617 static struct attribute *vf610_attributes[] = { 618 &iio_dev_attr_sampling_frequency_available.dev_attr.attr, 619 NULL 620 }; 621 622 static const struct attribute_group vf610_attribute_group = { 623 .attrs = vf610_attributes, 624 }; 625 626 static int vf610_read_raw(struct iio_dev *indio_dev, 627 struct iio_chan_spec const *chan, 628 int *val, 629 int *val2, 630 long mask) 631 { 632 struct vf610_adc *info = iio_priv(indio_dev); 633 unsigned int hc_cfg; 634 long ret; 635 636 switch (mask) { 637 case IIO_CHAN_INFO_RAW: 638 case IIO_CHAN_INFO_PROCESSED: 639 mutex_lock(&indio_dev->mlock); 640 if (iio_buffer_enabled(indio_dev)) { 641 mutex_unlock(&indio_dev->mlock); 642 return -EBUSY; 643 } 644 645 reinit_completion(&info->completion); 646 hc_cfg = VF610_ADC_ADCHC(chan->channel); 647 hc_cfg |= VF610_ADC_AIEN; 648 writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); 649 ret = wait_for_completion_interruptible_timeout 650 (&info->completion, VF610_ADC_TIMEOUT); 651 if (ret == 0) { 652 mutex_unlock(&indio_dev->mlock); 653 return -ETIMEDOUT; 654 } 655 if (ret < 0) { 656 mutex_unlock(&indio_dev->mlock); 657 return ret; 658 } 659 660 switch (chan->type) { 661 case IIO_VOLTAGE: 662 *val = info->value; 663 break; 664 case IIO_TEMP: 665 /* 666 * Calculate in degree Celsius times 1000 667 * Using the typical sensor slope of 1.84 mV/°C 668 * and VREFH_ADC at 3.3V, V at 25°C of 699 mV 669 */ 670 *val = 25000 - ((int)info->value - VF610_VTEMP25_3V3) * 671 1000000 / VF610_TEMP_SLOPE_COEFF; 672 673 break; 674 default: 675 mutex_unlock(&indio_dev->mlock); 676 return -EINVAL; 677 } 678 679 mutex_unlock(&indio_dev->mlock); 680 return IIO_VAL_INT; 681 682 case IIO_CHAN_INFO_SCALE: 683 *val = info->vref_uv / 1000; 684 *val2 = info->adc_feature.res_mode; 685 return IIO_VAL_FRACTIONAL_LOG2; 686 687 case IIO_CHAN_INFO_SAMP_FREQ: 688 *val = info->sample_freq_avail[info->adc_feature.sample_rate]; 689 *val2 = 0; 690 return IIO_VAL_INT; 691 692 default: 693 break; 694 } 695 696 return -EINVAL; 697 } 698 699 static int vf610_write_raw(struct iio_dev *indio_dev, 700 struct iio_chan_spec const *chan, 701 int val, 702 int val2, 703 long mask) 704 { 705 struct vf610_adc *info = iio_priv(indio_dev); 706 int i; 707 708 switch (mask) { 709 case IIO_CHAN_INFO_SAMP_FREQ: 710 for (i = 0; 711 i < ARRAY_SIZE(info->sample_freq_avail); 712 i++) 713 if (val == info->sample_freq_avail[i]) { 714 info->adc_feature.sample_rate = i; 715 vf610_adc_sample_set(info); 716 return 0; 717 } 718 break; 719 720 default: 721 break; 722 } 723 724 return -EINVAL; 725 } 726 727 static int vf610_adc_buffer_postenable(struct iio_dev *indio_dev) 728 { 729 struct vf610_adc *info = iio_priv(indio_dev); 730 unsigned int channel; 731 int val; 732 733 val = readl(info->regs + VF610_REG_ADC_GC); 734 val |= VF610_ADC_ADCON; 735 writel(val, info->regs + VF610_REG_ADC_GC); 736 737 channel = find_first_bit(indio_dev->active_scan_mask, 738 indio_dev->masklength); 739 740 val = VF610_ADC_ADCHC(channel); 741 val |= VF610_ADC_AIEN; 742 743 writel(val, info->regs + VF610_REG_ADC_HC0); 744 745 return 0; 746 } 747 748 static int vf610_adc_buffer_predisable(struct iio_dev *indio_dev) 749 { 750 struct vf610_adc *info = iio_priv(indio_dev); 751 unsigned int hc_cfg = 0; 752 int val; 753 754 val = readl(info->regs + VF610_REG_ADC_GC); 755 val &= ~VF610_ADC_ADCON; 756 writel(val, info->regs + VF610_REG_ADC_GC); 757 758 hc_cfg |= VF610_ADC_CONV_DISABLE; 759 hc_cfg &= ~VF610_ADC_AIEN; 760 761 writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); 762 763 return 0; 764 } 765 766 static const struct iio_buffer_setup_ops iio_triggered_buffer_setup_ops = { 767 .postenable = &vf610_adc_buffer_postenable, 768 .predisable = &vf610_adc_buffer_predisable, 769 .validate_scan_mask = &iio_validate_scan_mask_onehot, 770 }; 771 772 static int vf610_adc_reg_access(struct iio_dev *indio_dev, 773 unsigned reg, unsigned writeval, 774 unsigned *readval) 775 { 776 struct vf610_adc *info = iio_priv(indio_dev); 777 778 if ((readval == NULL) || 779 ((reg % 4) || (reg > VF610_REG_ADC_PCTL))) 780 return -EINVAL; 781 782 *readval = readl(info->regs + reg); 783 784 return 0; 785 } 786 787 static const struct iio_info vf610_adc_iio_info = { 788 .read_raw = &vf610_read_raw, 789 .write_raw = &vf610_write_raw, 790 .debugfs_reg_access = &vf610_adc_reg_access, 791 .attrs = &vf610_attribute_group, 792 }; 793 794 static const struct of_device_id vf610_adc_match[] = { 795 { .compatible = "fsl,vf610-adc", }, 796 { /* sentinel */ } 797 }; 798 MODULE_DEVICE_TABLE(of, vf610_adc_match); 799 800 static int vf610_adc_probe(struct platform_device *pdev) 801 { 802 struct vf610_adc *info; 803 struct iio_dev *indio_dev; 804 int irq; 805 int ret; 806 807 indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(struct vf610_adc)); 808 if (!indio_dev) { 809 dev_err(&pdev->dev, "Failed allocating iio device\n"); 810 return -ENOMEM; 811 } 812 813 info = iio_priv(indio_dev); 814 info->dev = &pdev->dev; 815 816 info->regs = devm_platform_ioremap_resource(pdev, 0); 817 if (IS_ERR(info->regs)) 818 return PTR_ERR(info->regs); 819 820 irq = platform_get_irq(pdev, 0); 821 if (irq < 0) 822 return irq; 823 824 ret = devm_request_irq(info->dev, irq, 825 vf610_adc_isr, 0, 826 dev_name(&pdev->dev), indio_dev); 827 if (ret < 0) { 828 dev_err(&pdev->dev, "failed requesting irq, irq = %d\n", irq); 829 return ret; 830 } 831 832 info->clk = devm_clk_get(&pdev->dev, "adc"); 833 if (IS_ERR(info->clk)) { 834 dev_err(&pdev->dev, "failed getting clock, err = %ld\n", 835 PTR_ERR(info->clk)); 836 return PTR_ERR(info->clk); 837 } 838 839 info->vref = devm_regulator_get(&pdev->dev, "vref"); 840 if (IS_ERR(info->vref)) 841 return PTR_ERR(info->vref); 842 843 ret = regulator_enable(info->vref); 844 if (ret) 845 return ret; 846 847 info->vref_uv = regulator_get_voltage(info->vref); 848 849 of_property_read_u32_array(pdev->dev.of_node, "fsl,adck-max-frequency", 850 info->max_adck_rate, 3); 851 852 ret = of_property_read_u32(pdev->dev.of_node, "min-sample-time", 853 &info->adc_feature.default_sample_time); 854 if (ret) 855 info->adc_feature.default_sample_time = DEFAULT_SAMPLE_TIME; 856 857 platform_set_drvdata(pdev, indio_dev); 858 859 init_completion(&info->completion); 860 861 indio_dev->name = dev_name(&pdev->dev); 862 indio_dev->info = &vf610_adc_iio_info; 863 indio_dev->modes = INDIO_DIRECT_MODE; 864 indio_dev->channels = vf610_adc_iio_channels; 865 indio_dev->num_channels = ARRAY_SIZE(vf610_adc_iio_channels); 866 867 ret = clk_prepare_enable(info->clk); 868 if (ret) { 869 dev_err(&pdev->dev, 870 "Could not prepare or enable the clock.\n"); 871 goto error_adc_clk_enable; 872 } 873 874 vf610_adc_cfg_init(info); 875 vf610_adc_hw_init(info); 876 877 ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, 878 NULL, &iio_triggered_buffer_setup_ops); 879 if (ret < 0) { 880 dev_err(&pdev->dev, "Couldn't initialise the buffer\n"); 881 goto error_iio_device_register; 882 } 883 884 ret = iio_device_register(indio_dev); 885 if (ret) { 886 dev_err(&pdev->dev, "Couldn't register the device.\n"); 887 goto error_adc_buffer_init; 888 } 889 890 return 0; 891 892 error_adc_buffer_init: 893 iio_triggered_buffer_cleanup(indio_dev); 894 error_iio_device_register: 895 clk_disable_unprepare(info->clk); 896 error_adc_clk_enable: 897 regulator_disable(info->vref); 898 899 return ret; 900 } 901 902 static int vf610_adc_remove(struct platform_device *pdev) 903 { 904 struct iio_dev *indio_dev = platform_get_drvdata(pdev); 905 struct vf610_adc *info = iio_priv(indio_dev); 906 907 iio_device_unregister(indio_dev); 908 iio_triggered_buffer_cleanup(indio_dev); 909 regulator_disable(info->vref); 910 clk_disable_unprepare(info->clk); 911 912 return 0; 913 } 914 915 static int vf610_adc_suspend(struct device *dev) 916 { 917 struct iio_dev *indio_dev = dev_get_drvdata(dev); 918 struct vf610_adc *info = iio_priv(indio_dev); 919 int hc_cfg; 920 921 /* ADC controller enters to stop mode */ 922 hc_cfg = readl(info->regs + VF610_REG_ADC_HC0); 923 hc_cfg |= VF610_ADC_CONV_DISABLE; 924 writel(hc_cfg, info->regs + VF610_REG_ADC_HC0); 925 926 clk_disable_unprepare(info->clk); 927 regulator_disable(info->vref); 928 929 return 0; 930 } 931 932 static int vf610_adc_resume(struct device *dev) 933 { 934 struct iio_dev *indio_dev = dev_get_drvdata(dev); 935 struct vf610_adc *info = iio_priv(indio_dev); 936 int ret; 937 938 ret = regulator_enable(info->vref); 939 if (ret) 940 return ret; 941 942 ret = clk_prepare_enable(info->clk); 943 if (ret) 944 goto disable_reg; 945 946 vf610_adc_hw_init(info); 947 948 return 0; 949 950 disable_reg: 951 regulator_disable(info->vref); 952 return ret; 953 } 954 955 static DEFINE_SIMPLE_DEV_PM_OPS(vf610_adc_pm_ops, vf610_adc_suspend, 956 vf610_adc_resume); 957 958 static struct platform_driver vf610_adc_driver = { 959 .probe = vf610_adc_probe, 960 .remove = vf610_adc_remove, 961 .driver = { 962 .name = DRIVER_NAME, 963 .of_match_table = vf610_adc_match, 964 .pm = pm_sleep_ptr(&vf610_adc_pm_ops), 965 }, 966 }; 967 968 module_platform_driver(vf610_adc_driver); 969 970 MODULE_AUTHOR("Fugang Duan <B38611@freescale.com>"); 971 MODULE_DESCRIPTION("Freescale VF610 ADC driver"); 972 MODULE_LICENSE("GPL v2"); 973