drivers/iio/adc/ingenic-adc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ADC driver for the Ingenic JZ47xx SoCs
   4  * Copyright (c) 2019 Artur Rojek <contact@artur-rojek.eu>
   5  *
   6  * based on drivers/mfd/jz4740-adc.c
   7  */
   8
   9 #include <dt-bindings/iio/adc/ingenic,adc.h>
  10 #include <linux/clk.h>
  11 #include <linux/iio/buffer.h>
  12 #include <linux/iio/iio.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/io.h>
  15 #include <linux/iopoll.h>
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/mod_devicetable.h>
  19 #include <linux/mutex.h>
  20 #include <linux/of.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/property.h>
  23
  24 #define JZ_ADC_REG_ENABLE               0x00
  25 #define JZ_ADC_REG_CFG                  0x04
  26 #define JZ_ADC_REG_CTRL                 0x08
  27 #define JZ_ADC_REG_STATUS               0x0c
  28 #define JZ_ADC_REG_ADSAME               0x10
  29 #define JZ_ADC_REG_ADWAIT               0x14
  30 #define JZ_ADC_REG_ADTCH                0x18
  31 #define JZ_ADC_REG_ADBDAT               0x1c
  32 #define JZ_ADC_REG_ADSDAT               0x20
  33 #define JZ_ADC_REG_ADCMD                0x24
  34 #define JZ_ADC_REG_ADCLK                0x28
  35
  36 #define JZ_ADC_REG_ENABLE_PD            BIT(7)
  37 #define JZ_ADC_REG_CFG_AUX_MD           (BIT(0) | BIT(1))
  38 #define JZ_ADC_REG_CFG_BAT_MD           BIT(4)
  39 #define JZ_ADC_REG_CFG_SAMPLE_NUM(n)    ((n) << 10)
  40 #define JZ_ADC_REG_CFG_PULL_UP(n)       ((n) << 16)
  41 #define JZ_ADC_REG_CFG_CMD_SEL          BIT(22)
  42 #define JZ_ADC_REG_CFG_VBAT_SEL         BIT(30)
  43 #define JZ_ADC_REG_CFG_TOUCH_OPS_MASK   (BIT(31) | GENMASK(23, 10))
  44 #define JZ_ADC_REG_ADCLK_CLKDIV_LSB     0
  45 #define JZ4725B_ADC_REG_ADCLK_CLKDIV10US_LSB    16
  46 #define JZ4770_ADC_REG_ADCLK_CLKDIV10US_LSB     8
  47 #define JZ4770_ADC_REG_ADCLK_CLKDIVMS_LSB       16
  48
  49 #define JZ_ADC_REG_ADCMD_YNADC          BIT(7)
  50 #define JZ_ADC_REG_ADCMD_YPADC          BIT(8)
  51 #define JZ_ADC_REG_ADCMD_XNADC          BIT(9)
  52 #define JZ_ADC_REG_ADCMD_XPADC          BIT(10)
  53 #define JZ_ADC_REG_ADCMD_VREFPYP        BIT(11)
  54 #define JZ_ADC_REG_ADCMD_VREFPXP        BIT(12)
  55 #define JZ_ADC_REG_ADCMD_VREFPXN        BIT(13)
  56 #define JZ_ADC_REG_ADCMD_VREFPAUX       BIT(14)
  57 #define JZ_ADC_REG_ADCMD_VREFPVDD33     BIT(15)
  58 #define JZ_ADC_REG_ADCMD_VREFNYN        BIT(16)
  59 #define JZ_ADC_REG_ADCMD_VREFNXP        BIT(17)
  60 #define JZ_ADC_REG_ADCMD_VREFNXN        BIT(18)
  61 #define JZ_ADC_REG_ADCMD_VREFAUX        BIT(19)
  62 #define JZ_ADC_REG_ADCMD_YNGRU          BIT(20)
  63 #define JZ_ADC_REG_ADCMD_XNGRU          BIT(21)
  64 #define JZ_ADC_REG_ADCMD_XPGRU          BIT(22)
  65 #define JZ_ADC_REG_ADCMD_YPSUP          BIT(23)
  66 #define JZ_ADC_REG_ADCMD_XNSUP          BIT(24)
  67 #define JZ_ADC_REG_ADCMD_XPSUP          BIT(25)
  68
  69 #define JZ_ADC_AUX_VREF                         3300
  70 #define JZ_ADC_AUX_VREF_BITS                    12
  71 #define JZ_ADC_BATTERY_LOW_VREF                 2500
  72 #define JZ_ADC_BATTERY_LOW_VREF_BITS            12
  73 #define JZ4725B_ADC_BATTERY_HIGH_VREF           7500
  74 #define JZ4725B_ADC_BATTERY_HIGH_VREF_BITS      10
  75 #define JZ4740_ADC_BATTERY_HIGH_VREF            (7500 * 0.986)
  76 #define JZ4740_ADC_BATTERY_HIGH_VREF_BITS       12
  77 #define JZ4760_ADC_BATTERY_VREF                 2500
  78 #define JZ4770_ADC_BATTERY_VREF                 1200
  79 #define JZ4770_ADC_BATTERY_VREF_BITS            12
  80
  81 #define JZ_ADC_IRQ_AUX                  BIT(0)
  82 #define JZ_ADC_IRQ_BATTERY              BIT(1)
  83 #define JZ_ADC_IRQ_TOUCH                BIT(2)
  84 #define JZ_ADC_IRQ_PEN_DOWN             BIT(3)
  85 #define JZ_ADC_IRQ_PEN_UP               BIT(4)
  86 #define JZ_ADC_IRQ_PEN_DOWN_SLEEP       BIT(5)
  87 #define JZ_ADC_IRQ_SLEEP                BIT(7)
  88
  89 struct ingenic_adc;
  90
  91 struct ingenic_adc_soc_data {
  92         unsigned int battery_high_vref;
  93         unsigned int battery_high_vref_bits;
  94         const int *battery_raw_avail;
  95         size_t battery_raw_avail_size;
  96         const int *battery_scale_avail;
  97         size_t battery_scale_avail_size;
  98         unsigned int battery_vref_mode: 1;
  99         unsigned int has_aux_md: 1;
 100         const struct iio_chan_spec *channels;
 101         unsigned int num_channels;
 102         int (*init_clk_div)(struct device *dev, struct ingenic_adc *adc);
 103 };
 104
 105 struct ingenic_adc {
 106         void __iomem *base;
 107         struct clk *clk;
 108         struct mutex lock;
 109         struct mutex aux_lock;
 110         const struct ingenic_adc_soc_data *soc_data;
 111         bool low_vref_mode;
 112 };
 113
 114 static void ingenic_adc_set_adcmd(struct iio_dev *iio_dev, unsigned long mask)
 115 {
 116         struct ingenic_adc *adc = iio_priv(iio_dev);
 117
 118         mutex_lock(&adc->lock);
 119
 120         /* Init ADCMD */
 121         readl(adc->base + JZ_ADC_REG_ADCMD);
 122
 123         if (mask & 0x3) {
 124                 /* Second channel (INGENIC_ADC_TOUCH_YP): sample YP vs. GND */
 125                 writel(JZ_ADC_REG_ADCMD_XNGRU
 126                        | JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
 127                        | JZ_ADC_REG_ADCMD_YPADC,
 128                        adc->base + JZ_ADC_REG_ADCMD);
 129
 130                 /* First channel (INGENIC_ADC_TOUCH_XP): sample XP vs. GND */
 131                 writel(JZ_ADC_REG_ADCMD_YNGRU
 132                        | JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
 133                        | JZ_ADC_REG_ADCMD_XPADC,
 134                        adc->base + JZ_ADC_REG_ADCMD);
 135         }
 136
 137         if (mask & 0xc) {
 138                 /* Fourth channel (INGENIC_ADC_TOUCH_YN): sample YN vs. GND */
 139                 writel(JZ_ADC_REG_ADCMD_XNGRU
 140                        | JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
 141                        | JZ_ADC_REG_ADCMD_YNADC,
 142                        adc->base + JZ_ADC_REG_ADCMD);
 143
 144                 /* Third channel (INGENIC_ADC_TOUCH_XN): sample XN vs. GND */
 145                 writel(JZ_ADC_REG_ADCMD_YNGRU
 146                        | JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
 147                        | JZ_ADC_REG_ADCMD_XNADC,
 148                        adc->base + JZ_ADC_REG_ADCMD);
 149         }
 150
 151         if (mask & 0x30) {
 152                 /* Sixth channel (INGENIC_ADC_TOUCH_YD): sample YP vs. YN */
 153                 writel(JZ_ADC_REG_ADCMD_VREFNYN | JZ_ADC_REG_ADCMD_VREFPVDD33
 154                        | JZ_ADC_REG_ADCMD_YPADC,
 155                        adc->base + JZ_ADC_REG_ADCMD);
 156
 157                 /* Fifth channel (INGENIC_ADC_TOUCH_XD): sample XP vs. XN */
 158                 writel(JZ_ADC_REG_ADCMD_VREFNXN | JZ_ADC_REG_ADCMD_VREFPVDD33
 159                        | JZ_ADC_REG_ADCMD_XPADC,
 160                        adc->base + JZ_ADC_REG_ADCMD);
 161         }
 162
 163         /* We're done */
 164         writel(0, adc->base + JZ_ADC_REG_ADCMD);
 165
 166         mutex_unlock(&adc->lock);
 167 }
 168
 169 static void ingenic_adc_set_config(struct ingenic_adc *adc,
 170                                    uint32_t mask,
 171                                    uint32_t val)
 172 {
 173         uint32_t cfg;
 174
 175         mutex_lock(&adc->lock);
 176
 177         cfg = readl(adc->base + JZ_ADC_REG_CFG) & ~mask;
 178         cfg |= val;
 179         writel(cfg, adc->base + JZ_ADC_REG_CFG);
 180
 181         mutex_unlock(&adc->lock);
 182 }
 183
 184 static void ingenic_adc_enable_unlocked(struct ingenic_adc *adc,
 185                                         int engine,
 186                                         bool enabled)
 187 {
 188         u8 val;
 189
 190         val = readb(adc->base + JZ_ADC_REG_ENABLE);
 191
 192         if (enabled)
 193                 val |= BIT(engine);
 194         else
 195                 val &= ~BIT(engine);
 196
 197         writeb(val, adc->base + JZ_ADC_REG_ENABLE);
 198 }
 199
 200 static void ingenic_adc_enable(struct ingenic_adc *adc,
 201                                int engine,
 202                                bool enabled)
 203 {
 204         mutex_lock(&adc->lock);
 205         ingenic_adc_enable_unlocked(adc, engine, enabled);
 206         mutex_unlock(&adc->lock);
 207 }
 208
 209 static int ingenic_adc_capture(struct ingenic_adc *adc,
 210                                int engine)
 211 {
 212         u32 cfg;
 213         u8 val;
 214         int ret;
 215
 216         /*
 217          * Disable CMD_SEL temporarily, because it causes wrong VBAT readings,
 218          * probably due to the switch of VREF. We must keep the lock here to
 219          * avoid races with the buffer enable/disable functions.
 220          */
 221         mutex_lock(&adc->lock);
 222         cfg = readl(adc->base + JZ_ADC_REG_CFG);
 223         writel(cfg & ~JZ_ADC_REG_CFG_CMD_SEL, adc->base + JZ_ADC_REG_CFG);
 224
 225         ingenic_adc_enable_unlocked(adc, engine, true);
 226         ret = readb_poll_timeout(adc->base + JZ_ADC_REG_ENABLE, val,
 227                                  !(val & BIT(engine)), 250, 1000);
 228         if (ret)
 229                 ingenic_adc_enable_unlocked(adc, engine, false);
 230
 231         writel(cfg, adc->base + JZ_ADC_REG_CFG);
 232         mutex_unlock(&adc->lock);
 233
 234         return ret;
 235 }
 236
 237 static int ingenic_adc_write_raw(struct iio_dev *iio_dev,
 238                                  struct iio_chan_spec const *chan,
 239                                  int val,
 240                                  int val2,
 241                                  long m)
 242 {
 243         struct ingenic_adc *adc = iio_priv(iio_dev);
 244         struct device *dev = iio_dev->dev.parent;
 245         int ret;
 246
 247         switch (m) {
 248         case IIO_CHAN_INFO_SCALE:
 249                 switch (chan->channel) {
 250                 case INGENIC_ADC_BATTERY:
 251                         if (!adc->soc_data->battery_vref_mode)
 252                                 return -EINVAL;
 253
 254                         ret = clk_enable(adc->clk);
 255                         if (ret) {
 256                                 dev_err(dev, "Failed to enable clock: %d\n",
 257                                         ret);
 258                                 return ret;
 259                         }
 260
 261                         if (val > JZ_ADC_BATTERY_LOW_VREF) {
 262                                 ingenic_adc_set_config(adc,
 263                                                        JZ_ADC_REG_CFG_BAT_MD,
 264                                                        0);
 265                                 adc->low_vref_mode = false;
 266                         } else {
 267                                 ingenic_adc_set_config(adc,
 268                                                        JZ_ADC_REG_CFG_BAT_MD,
 269                                                        JZ_ADC_REG_CFG_BAT_MD);
 270                                 adc->low_vref_mode = true;
 271                         }
 272
 273                         clk_disable(adc->clk);
 274
 275                         return 0;
 276                 default:
 277                         return -EINVAL;
 278                 }
 279         default:
 280                 return -EINVAL;
 281         }
 282 }
 283
 284 static const int jz4725b_adc_battery_raw_avail[] = {
 285         0, 1, (1 << JZ_ADC_BATTERY_LOW_VREF_BITS) - 1,
 286 };
 287
 288 static const int jz4725b_adc_battery_scale_avail[] = {
 289         JZ4725B_ADC_BATTERY_HIGH_VREF, JZ4725B_ADC_BATTERY_HIGH_VREF_BITS,
 290         JZ_ADC_BATTERY_LOW_VREF, JZ_ADC_BATTERY_LOW_VREF_BITS,
 291 };
 292
 293 static const int jz4740_adc_battery_raw_avail[] = {
 294         0, 1, (1 << JZ_ADC_BATTERY_LOW_VREF_BITS) - 1,
 295 };
 296
 297 static const int jz4740_adc_battery_scale_avail[] = {
 298         JZ4740_ADC_BATTERY_HIGH_VREF, JZ4740_ADC_BATTERY_HIGH_VREF_BITS,
 299         JZ_ADC_BATTERY_LOW_VREF, JZ_ADC_BATTERY_LOW_VREF_BITS,
 300 };
 301
 302 static const int jz4760_adc_battery_scale_avail[] = {
 303         JZ4760_ADC_BATTERY_VREF, JZ4770_ADC_BATTERY_VREF_BITS,
 304 };
 305
 306 static const int jz4770_adc_battery_raw_avail[] = {
 307         0, 1, (1 << JZ4770_ADC_BATTERY_VREF_BITS) - 1,
 308 };
 309
 310 static const int jz4770_adc_battery_scale_avail[] = {
 311         JZ4770_ADC_BATTERY_VREF, JZ4770_ADC_BATTERY_VREF_BITS,
 312 };
 313
 314 static int jz4725b_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc)
 315 {
 316         struct clk *parent_clk;
 317         unsigned long parent_rate, rate;
 318         unsigned int div_main, div_10us;
 319
 320         parent_clk = clk_get_parent(adc->clk);
 321         if (!parent_clk) {
 322                 dev_err(dev, "ADC clock has no parent\n");
 323                 return -ENODEV;
 324         }
 325         parent_rate = clk_get_rate(parent_clk);
 326
 327         /*
 328          * The JZ4725B ADC works at 500 kHz to 8 MHz.
 329          * We pick the highest rate possible.
 330          * In practice we typically get 6 MHz, half of the 12 MHz EXT clock.
 331          */
 332         div_main = DIV_ROUND_UP(parent_rate, 8000000);
 333         div_main = clamp(div_main, 1u, 64u);
 334         rate = parent_rate / div_main;
 335         if (rate < 500000 || rate > 8000000) {
 336                 dev_err(dev, "No valid divider for ADC main clock\n");
 337                 return -EINVAL;
 338         }
 339
 340         /* We also need a divider that produces a 10us clock. */
 341         div_10us = DIV_ROUND_UP(rate, 100000);
 342
 343         writel(((div_10us - 1) << JZ4725B_ADC_REG_ADCLK_CLKDIV10US_LSB) |
 344                (div_main - 1) << JZ_ADC_REG_ADCLK_CLKDIV_LSB,
 345                adc->base + JZ_ADC_REG_ADCLK);
 346
 347         return 0;
 348 }
 349
 350 static int jz4770_adc_init_clk_div(struct device *dev, struct ingenic_adc *adc)
 351 {
 352         struct clk *parent_clk;
 353         unsigned long parent_rate, rate;
 354         unsigned int div_main, div_ms, div_10us;
 355
 356         parent_clk = clk_get_parent(adc->clk);
 357         if (!parent_clk) {
 358                 dev_err(dev, "ADC clock has no parent\n");
 359                 return -ENODEV;
 360         }
 361         parent_rate = clk_get_rate(parent_clk);
 362
 363         /*
 364          * The JZ4770 ADC works at 20 kHz to 200 kHz.
 365          * We pick the highest rate possible.
 366          */
 367         div_main = DIV_ROUND_UP(parent_rate, 200000);
 368         div_main = clamp(div_main, 1u, 256u);
 369         rate = parent_rate / div_main;
 370         if (rate < 20000 || rate > 200000) {
 371                 dev_err(dev, "No valid divider for ADC main clock\n");
 372                 return -EINVAL;
 373         }
 374
 375         /* We also need a divider that produces a 10us clock. */
 376         div_10us = DIV_ROUND_UP(rate, 10000);
 377         /* And another, which produces a 1ms clock. */
 378         div_ms = DIV_ROUND_UP(rate, 1000);
 379
 380         writel(((div_ms - 1) << JZ4770_ADC_REG_ADCLK_CLKDIVMS_LSB) |
 381                ((div_10us - 1) << JZ4770_ADC_REG_ADCLK_CLKDIV10US_LSB) |
 382                (div_main - 1) << JZ_ADC_REG_ADCLK_CLKDIV_LSB,
 383                adc->base + JZ_ADC_REG_ADCLK);
 384
 385         return 0;
 386 }
 387
 388 static const struct iio_chan_spec jz4740_channels[] = {
 389         {
 390                 .extend_name = "aux",
 391                 .type = IIO_VOLTAGE,
 392                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 393                                       BIT(IIO_CHAN_INFO_SCALE),
 394                 .indexed = 1,
 395                 .channel = INGENIC_ADC_AUX,
 396                 .scan_index = -1,
 397         },
 398         {
 399                 .extend_name = "battery",
 400                 .type = IIO_VOLTAGE,
 401                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 402                                       BIT(IIO_CHAN_INFO_SCALE),
 403                 .info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
 404                                                 BIT(IIO_CHAN_INFO_SCALE),
 405                 .indexed = 1,
 406                 .channel = INGENIC_ADC_BATTERY,
 407                 .scan_index = -1,
 408         },
 409 };
 410
 411 static const struct iio_chan_spec jz4760_channels[] = {
 412         {
 413                 .extend_name = "aux",
 414                 .type = IIO_VOLTAGE,
 415                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 416                                       BIT(IIO_CHAN_INFO_SCALE),
 417                 .indexed = 1,
 418                 .channel = INGENIC_ADC_AUX0,
 419                 .scan_index = -1,
 420         },
 421         {
 422                 .extend_name = "aux1",
 423                 .type = IIO_VOLTAGE,
 424                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 425                                       BIT(IIO_CHAN_INFO_SCALE),
 426                 .indexed = 1,
 427                 .channel = INGENIC_ADC_AUX,
 428                 .scan_index = -1,
 429         },
 430         {
 431                 .extend_name = "aux2",
 432                 .type = IIO_VOLTAGE,
 433                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 434                                       BIT(IIO_CHAN_INFO_SCALE),
 435                 .indexed = 1,
 436                 .channel = INGENIC_ADC_AUX2,
 437                 .scan_index = -1,
 438         },
 439         {
 440                 .extend_name = "battery",
 441                 .type = IIO_VOLTAGE,
 442                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 443                                       BIT(IIO_CHAN_INFO_SCALE),
 444                 .info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
 445                                                 BIT(IIO_CHAN_INFO_SCALE),
 446                 .indexed = 1,
 447                 .channel = INGENIC_ADC_BATTERY,
 448                 .scan_index = -1,
 449         },
 450 };
 451
 452 static const struct iio_chan_spec jz4770_channels[] = {
 453         {
 454                 .type = IIO_VOLTAGE,
 455                 .indexed = 1,
 456                 .channel = INGENIC_ADC_TOUCH_XP,
 457                 .scan_index = 0,
 458                 .scan_type = {
 459                         .sign = 'u',
 460                         .realbits = 12,
 461                         .storagebits = 16,
 462                 },
 463         },
 464         {
 465                 .type = IIO_VOLTAGE,
 466                 .indexed = 1,
 467                 .channel = INGENIC_ADC_TOUCH_YP,
 468                 .scan_index = 1,
 469                 .scan_type = {
 470                         .sign = 'u',
 471                         .realbits = 12,
 472                         .storagebits = 16,
 473                 },
 474         },
 475         {
 476                 .type = IIO_VOLTAGE,
 477                 .indexed = 1,
 478                 .channel = INGENIC_ADC_TOUCH_XN,
 479                 .scan_index = 2,
 480                 .scan_type = {
 481                         .sign = 'u',
 482                         .realbits = 12,
 483                         .storagebits = 16,
 484                 },
 485         },
 486         {
 487                 .type = IIO_VOLTAGE,
 488                 .indexed = 1,
 489                 .channel = INGENIC_ADC_TOUCH_YN,
 490                 .scan_index = 3,
 491                 .scan_type = {
 492                         .sign = 'u',
 493                         .realbits = 12,
 494                         .storagebits = 16,
 495                 },
 496         },
 497         {
 498                 .type = IIO_VOLTAGE,
 499                 .indexed = 1,
 500                 .channel = INGENIC_ADC_TOUCH_XD,
 501                 .scan_index = 4,
 502                 .scan_type = {
 503                         .sign = 'u',
 504                         .realbits = 12,
 505                         .storagebits = 16,
 506                 },
 507         },
 508         {
 509                 .type = IIO_VOLTAGE,
 510                 .indexed = 1,
 511                 .channel = INGENIC_ADC_TOUCH_YD,
 512                 .scan_index = 5,
 513                 .scan_type = {
 514                         .sign = 'u',
 515                         .realbits = 12,
 516                         .storagebits = 16,
 517                 },
 518         },
 519         {
 520                 .extend_name = "aux",
 521                 .type = IIO_VOLTAGE,
 522                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 523                                       BIT(IIO_CHAN_INFO_SCALE),
 524                 .indexed = 1,
 525                 .channel = INGENIC_ADC_AUX,
 526                 .scan_index = -1,
 527         },
 528         {
 529                 .extend_name = "battery",
 530                 .type = IIO_VOLTAGE,
 531                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 532                                       BIT(IIO_CHAN_INFO_SCALE),
 533                 .info_mask_separate_available = BIT(IIO_CHAN_INFO_RAW) |
 534                                                 BIT(IIO_CHAN_INFO_SCALE),
 535                 .indexed = 1,
 536                 .channel = INGENIC_ADC_BATTERY,
 537                 .scan_index = -1,
 538         },
 539         {
 540                 .extend_name = "aux2",
 541                 .type = IIO_VOLTAGE,
 542                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 543                                       BIT(IIO_CHAN_INFO_SCALE),
 544                 .indexed = 1,
 545                 .channel = INGENIC_ADC_AUX2,
 546                 .scan_index = -1,
 547         },
 548 };
 549
 550 static const struct ingenic_adc_soc_data jz4725b_adc_soc_data = {
 551         .battery_high_vref = JZ4725B_ADC_BATTERY_HIGH_VREF,
 552         .battery_high_vref_bits = JZ4725B_ADC_BATTERY_HIGH_VREF_BITS,
 553         .battery_raw_avail = jz4725b_adc_battery_raw_avail,
 554         .battery_raw_avail_size = ARRAY_SIZE(jz4725b_adc_battery_raw_avail),
 555         .battery_scale_avail = jz4725b_adc_battery_scale_avail,
 556         .battery_scale_avail_size = ARRAY_SIZE(jz4725b_adc_battery_scale_avail),
 557         .battery_vref_mode = true,
 558         .has_aux_md = false,
 559         .channels = jz4740_channels,
 560         .num_channels = ARRAY_SIZE(jz4740_channels),
 561         .init_clk_div = jz4725b_adc_init_clk_div,
 562 };
 563
 564 static const struct ingenic_adc_soc_data jz4740_adc_soc_data = {
 565         .battery_high_vref = JZ4740_ADC_BATTERY_HIGH_VREF,
 566         .battery_high_vref_bits = JZ4740_ADC_BATTERY_HIGH_VREF_BITS,
 567         .battery_raw_avail = jz4740_adc_battery_raw_avail,
 568         .battery_raw_avail_size = ARRAY_SIZE(jz4740_adc_battery_raw_avail),
 569         .battery_scale_avail = jz4740_adc_battery_scale_avail,
 570         .battery_scale_avail_size = ARRAY_SIZE(jz4740_adc_battery_scale_avail),
 571         .battery_vref_mode = true,
 572         .has_aux_md = false,
 573         .channels = jz4740_channels,
 574         .num_channels = ARRAY_SIZE(jz4740_channels),
 575         .init_clk_div = NULL, /* no ADCLK register on JZ4740 */
 576 };
 577
 578 static const struct ingenic_adc_soc_data jz4760_adc_soc_data = {
 579         .battery_high_vref = JZ4760_ADC_BATTERY_VREF,
 580         .battery_high_vref_bits = JZ4770_ADC_BATTERY_VREF_BITS,
 581         .battery_raw_avail = jz4770_adc_battery_raw_avail,
 582         .battery_raw_avail_size = ARRAY_SIZE(jz4770_adc_battery_raw_avail),
 583         .battery_scale_avail = jz4760_adc_battery_scale_avail,
 584         .battery_scale_avail_size = ARRAY_SIZE(jz4760_adc_battery_scale_avail),
 585         .battery_vref_mode = false,
 586         .has_aux_md = true,
 587         .channels = jz4760_channels,
 588         .num_channels = ARRAY_SIZE(jz4760_channels),
 589         .init_clk_div = jz4770_adc_init_clk_div,
 590 };
 591
 592 static const struct ingenic_adc_soc_data jz4770_adc_soc_data = {
 593         .battery_high_vref = JZ4770_ADC_BATTERY_VREF,
 594         .battery_high_vref_bits = JZ4770_ADC_BATTERY_VREF_BITS,
 595         .battery_raw_avail = jz4770_adc_battery_raw_avail,
 596         .battery_raw_avail_size = ARRAY_SIZE(jz4770_adc_battery_raw_avail),
 597         .battery_scale_avail = jz4770_adc_battery_scale_avail,
 598         .battery_scale_avail_size = ARRAY_SIZE(jz4770_adc_battery_scale_avail),
 599         .battery_vref_mode = false,
 600         .has_aux_md = true,
 601         .channels = jz4770_channels,
 602         .num_channels = ARRAY_SIZE(jz4770_channels),
 603         .init_clk_div = jz4770_adc_init_clk_div,
 604 };
 605
 606 static int ingenic_adc_read_avail(struct iio_dev *iio_dev,
 607                                   struct iio_chan_spec const *chan,
 608                                   const int **vals,
 609                                   int *type,
 610                                   int *length,
 611                                   long m)
 612 {
 613         struct ingenic_adc *adc = iio_priv(iio_dev);
 614
 615         switch (m) {
 616         case IIO_CHAN_INFO_RAW:
 617                 *type = IIO_VAL_INT;
 618                 *length = adc->soc_data->battery_raw_avail_size;
 619                 *vals = adc->soc_data->battery_raw_avail;
 620                 return IIO_AVAIL_RANGE;
 621         case IIO_CHAN_INFO_SCALE:
 622                 *type = IIO_VAL_FRACTIONAL_LOG2;
 623                 *length = adc->soc_data->battery_scale_avail_size;
 624                 *vals = adc->soc_data->battery_scale_avail;
 625                 return IIO_AVAIL_LIST;
 626         default:
 627                 return -EINVAL;
 628         }
 629 }
 630
 631 static int ingenic_adc_read_chan_info_raw(struct iio_dev *iio_dev,
 632                                           struct iio_chan_spec const *chan,
 633                                           int *val)
 634 {
 635         int cmd, ret, engine = (chan->channel == INGENIC_ADC_BATTERY);
 636         struct ingenic_adc *adc = iio_priv(iio_dev);
 637
 638         ret = clk_enable(adc->clk);
 639         if (ret) {
 640                 dev_err(iio_dev->dev.parent, "Failed to enable clock: %d\n",
 641                         ret);
 642                 return ret;
 643         }
 644
 645         /* We cannot sample the aux channels in parallel. */
 646         mutex_lock(&adc->aux_lock);
 647         if (adc->soc_data->has_aux_md && engine == 0) {
 648                 switch (chan->channel) {
 649                 case INGENIC_ADC_AUX0:
 650                         cmd = 0;
 651                         break;
 652                 case INGENIC_ADC_AUX:
 653                         cmd = 1;
 654                         break;
 655                 case INGENIC_ADC_AUX2:
 656                         cmd = 2;
 657                         break;
 658                 }
 659
 660                 ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_AUX_MD, cmd);
 661         }
 662
 663         ret = ingenic_adc_capture(adc, engine);
 664         if (ret)
 665                 goto out;
 666
 667         switch (chan->channel) {
 668         case INGENIC_ADC_AUX0:
 669         case INGENIC_ADC_AUX:
 670         case INGENIC_ADC_AUX2:
 671                 *val = readw(adc->base + JZ_ADC_REG_ADSDAT);
 672                 break;
 673         case INGENIC_ADC_BATTERY:
 674                 *val = readw(adc->base + JZ_ADC_REG_ADBDAT);
 675                 break;
 676         }
 677
 678         ret = IIO_VAL_INT;
 679 out:
 680         mutex_unlock(&adc->aux_lock);
 681         clk_disable(adc->clk);
 682
 683         return ret;
 684 }
 685
 686 static int ingenic_adc_read_raw(struct iio_dev *iio_dev,
 687                                 struct iio_chan_spec const *chan,
 688                                 int *val,
 689                                 int *val2,
 690                                 long m)
 691 {
 692         struct ingenic_adc *adc = iio_priv(iio_dev);
 693
 694         switch (m) {
 695         case IIO_CHAN_INFO_RAW:
 696                 return ingenic_adc_read_chan_info_raw(iio_dev, chan, val);
 697         case IIO_CHAN_INFO_SCALE:
 698                 switch (chan->channel) {
 699                 case INGENIC_ADC_AUX0:
 700                 case INGENIC_ADC_AUX:
 701                 case INGENIC_ADC_AUX2:
 702                         *val = JZ_ADC_AUX_VREF;
 703                         *val2 = JZ_ADC_AUX_VREF_BITS;
 704                         break;
 705                 case INGENIC_ADC_BATTERY:
 706                         if (adc->low_vref_mode) {
 707                                 *val = JZ_ADC_BATTERY_LOW_VREF;
 708                                 *val2 = JZ_ADC_BATTERY_LOW_VREF_BITS;
 709                         } else {
 710                                 *val = adc->soc_data->battery_high_vref;
 711                                 *val2 = adc->soc_data->battery_high_vref_bits;
 712                         }
 713                         break;
 714                 }
 715
 716                 return IIO_VAL_FRACTIONAL_LOG2;
 717         default:
 718                 return -EINVAL;
 719         }
 720 }
 721
 722 static int ingenic_adc_fwnode_xlate(struct iio_dev *iio_dev,
 723                                     const struct fwnode_reference_args *iiospec)
 724 {
 725         int i;
 726
 727         if (!iiospec->nargs)
 728                 return -EINVAL;
 729
 730         for (i = 0; i < iio_dev->num_channels; ++i)
 731                 if (iio_dev->channels[i].channel == iiospec->args[0])
 732                         return i;
 733
 734         return -EINVAL;
 735 }
 736
 737 static const struct iio_info ingenic_adc_info = {
 738         .write_raw = ingenic_adc_write_raw,
 739         .read_raw = ingenic_adc_read_raw,
 740         .read_avail = ingenic_adc_read_avail,
 741         .fwnode_xlate = ingenic_adc_fwnode_xlate,
 742 };
 743
 744 static int ingenic_adc_buffer_enable(struct iio_dev *iio_dev)
 745 {
 746         struct ingenic_adc *adc = iio_priv(iio_dev);
 747         int ret;
 748
 749         ret = clk_enable(adc->clk);
 750         if (ret) {
 751                 dev_err(iio_dev->dev.parent, "Failed to enable clock: %d\n",
 752                         ret);
 753                 return ret;
 754         }
 755
 756         /* It takes significant time for the touchscreen hw to stabilize. */
 757         msleep(50);
 758         ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK,
 759                                JZ_ADC_REG_CFG_SAMPLE_NUM(4) |
 760                                JZ_ADC_REG_CFG_PULL_UP(4));
 761
 762         writew(80, adc->base + JZ_ADC_REG_ADWAIT);
 763         writew(2, adc->base + JZ_ADC_REG_ADSAME);
 764         writeb((u8)~JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_CTRL);
 765         writel(0, adc->base + JZ_ADC_REG_ADTCH);
 766
 767         ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_CMD_SEL,
 768                                JZ_ADC_REG_CFG_CMD_SEL);
 769         ingenic_adc_set_adcmd(iio_dev, iio_dev->active_scan_mask[0]);
 770
 771         ingenic_adc_enable(adc, 2, true);
 772
 773         return 0;
 774 }
 775
 776 static int ingenic_adc_buffer_disable(struct iio_dev *iio_dev)
 777 {
 778         struct ingenic_adc *adc = iio_priv(iio_dev);
 779
 780         ingenic_adc_enable(adc, 2, false);
 781
 782         ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_CMD_SEL, 0);
 783
 784         writeb(0xff, adc->base + JZ_ADC_REG_CTRL);
 785         writeb(0xff, adc->base + JZ_ADC_REG_STATUS);
 786         ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_TOUCH_OPS_MASK, 0);
 787         writew(0, adc->base + JZ_ADC_REG_ADSAME);
 788         writew(0, adc->base + JZ_ADC_REG_ADWAIT);
 789         clk_disable(adc->clk);
 790
 791         return 0;
 792 }
 793
 794 static const struct iio_buffer_setup_ops ingenic_buffer_setup_ops = {
 795         .postenable = &ingenic_adc_buffer_enable,
 796         .predisable = &ingenic_adc_buffer_disable
 797 };
 798
 799 static irqreturn_t ingenic_adc_irq(int irq, void *data)
 800 {
 801         struct iio_dev *iio_dev = data;
 802         struct ingenic_adc *adc = iio_priv(iio_dev);
 803         unsigned long mask = iio_dev->active_scan_mask[0];
 804         unsigned int i;
 805         u32 tdat[3];
 806
 807         for (i = 0; i < ARRAY_SIZE(tdat); mask >>= 2, i++) {
 808                 if (mask & 0x3)
 809                         tdat[i] = readl(adc->base + JZ_ADC_REG_ADTCH);
 810                 else
 811                         tdat[i] = 0;
 812         }
 813
 814         iio_push_to_buffers(iio_dev, tdat);
 815         writeb(JZ_ADC_IRQ_TOUCH, adc->base + JZ_ADC_REG_STATUS);
 816
 817         return IRQ_HANDLED;
 818 }
 819
 820 static int ingenic_adc_probe(struct platform_device *pdev)
 821 {
 822         struct device *dev = &pdev->dev;
 823         struct iio_dev *iio_dev;
 824         struct ingenic_adc *adc;
 825         const struct ingenic_adc_soc_data *soc_data;
 826         int irq, ret;
 827
 828         soc_data = device_get_match_data(dev);
 829         if (!soc_data)
 830                 return -EINVAL;
 831
 832         iio_dev = devm_iio_device_alloc(dev, sizeof(*adc));
 833         if (!iio_dev)
 834                 return -ENOMEM;
 835
 836         adc = iio_priv(iio_dev);
 837         mutex_init(&adc->lock);
 838         mutex_init(&adc->aux_lock);
 839         adc->soc_data = soc_data;
 840
 841         irq = platform_get_irq(pdev, 0);
 842         if (irq < 0)
 843                 return irq;
 844
 845         ret = devm_request_irq(dev, irq, ingenic_adc_irq, 0,
 846                                dev_name(dev), iio_dev);
 847         if (ret < 0) {
 848                 dev_err(dev, "Failed to request irq: %d\n", ret);
 849                 return ret;
 850         }
 851
 852         adc->base = devm_platform_ioremap_resource(pdev, 0);
 853         if (IS_ERR(adc->base))
 854                 return PTR_ERR(adc->base);
 855
 856         adc->clk = devm_clk_get_prepared(dev, "adc");
 857         if (IS_ERR(adc->clk)) {
 858                 dev_err(dev, "Unable to get clock\n");
 859                 return PTR_ERR(adc->clk);
 860         }
 861
 862         ret = clk_enable(adc->clk);
 863         if (ret) {
 864                 dev_err(dev, "Failed to enable clock\n");
 865                 return ret;
 866         }
 867
 868         /* Set clock dividers. */
 869         if (soc_data->init_clk_div) {
 870                 ret = soc_data->init_clk_div(dev, adc);
 871                 if (ret) {
 872                         clk_disable_unprepare(adc->clk);
 873                         return ret;
 874                 }
 875         }
 876
 877         /* Put hardware in a known passive state. */
 878         writeb(0x00, adc->base + JZ_ADC_REG_ENABLE);
 879         writeb(0xff, adc->base + JZ_ADC_REG_CTRL);
 880
 881         /* JZ4760B specific */
 882         if (device_property_present(dev, "ingenic,use-internal-divider"))
 883                 ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_VBAT_SEL,
 884                                             JZ_ADC_REG_CFG_VBAT_SEL);
 885         else
 886                 ingenic_adc_set_config(adc, JZ_ADC_REG_CFG_VBAT_SEL, 0);
 887
 888         usleep_range(2000, 3000); /* Must wait at least 2ms. */
 889         clk_disable(adc->clk);
 890
 891         iio_dev->name = "jz-adc";
 892         iio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
 893         iio_dev->setup_ops = &ingenic_buffer_setup_ops;
 894         iio_dev->channels = soc_data->channels;
 895         iio_dev->num_channels = soc_data->num_channels;
 896         iio_dev->info = &ingenic_adc_info;
 897
 898         ret = devm_iio_device_register(dev, iio_dev);
 899         if (ret)
 900                 dev_err(dev, "Unable to register IIO device\n");
 901
 902         return ret;
 903 }
 904
 905 static const struct of_device_id ingenic_adc_of_match[] = {
 906         { .compatible = "ingenic,jz4725b-adc", .data = &jz4725b_adc_soc_data, },
 907         { .compatible = "ingenic,jz4740-adc", .data = &jz4740_adc_soc_data, },
 908         { .compatible = "ingenic,jz4760-adc", .data = &jz4760_adc_soc_data, },
 909         { .compatible = "ingenic,jz4760b-adc", .data = &jz4760_adc_soc_data, },
 910         { .compatible = "ingenic,jz4770-adc", .data = &jz4770_adc_soc_data, },
 911         { },
 912 };
 913 MODULE_DEVICE_TABLE(of, ingenic_adc_of_match);
 914
 915 static struct platform_driver ingenic_adc_driver = {
 916         .driver = {
 917                 .name = "ingenic-adc",
 918                 .of_match_table = ingenic_adc_of_match,
 919         },
 920         .probe = ingenic_adc_probe,
 921 };
 922 module_platform_driver(ingenic_adc_driver);
 923 MODULE_LICENSE("GPL v2");