drivers/iio/adc/bcm_iproc

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This source file includes following definitions.
iproc_adc_reg_dump
iproc_adc_interrupt_thread
iproc_adc_interrupt_handler
iproc_adc_do_read
iproc_adc_enable
iproc_adc_disable
iproc_adc_read_raw
iproc_adc_probe
iproc_adc_remove
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2016 Broadcom
   4  */
   5 
   6 #include <linux/module.h>
   7 #include <linux/of.h>
   8 #include <linux/io.h>
   9 #include <linux/clk.h>
  10 #include <linux/mfd/syscon.h>
  11 #include <linux/regmap.h>
  12 #include <linux/delay.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/platform_device.h>
  15 
  16 #include <linux/iio/iio.h>
  17 
  18 /* Below Register's are common to IPROC ADC and Touchscreen IP */
  19 #define IPROC_REGCTL1                   0x00
  20 #define IPROC_REGCTL2                   0x04
  21 #define IPROC_INTERRUPT_THRES           0x08
  22 #define IPROC_INTERRUPT_MASK            0x0c
  23 #define IPROC_INTERRUPT_STATUS          0x10
  24 #define IPROC_ANALOG_CONTROL            0x1c
  25 #define IPROC_CONTROLLER_STATUS         0x14
  26 #define IPROC_AUX_DATA                  0x20
  27 #define IPROC_SOFT_BYPASS_CONTROL       0x38
  28 #define IPROC_SOFT_BYPASS_DATA          0x3C
  29 
  30 /* IPROC ADC Channel register offsets */
  31 #define IPROC_ADC_CHANNEL_REGCTL1               0x800
  32 #define IPROC_ADC_CHANNEL_REGCTL2               0x804
  33 #define IPROC_ADC_CHANNEL_STATUS                0x808
  34 #define IPROC_ADC_CHANNEL_INTERRUPT_STATUS      0x80c
  35 #define IPROC_ADC_CHANNEL_INTERRUPT_MASK        0x810
  36 #define IPROC_ADC_CHANNEL_DATA                  0x814
  37 #define IPROC_ADC_CHANNEL_OFFSET                0x20
  38 
  39 /* Bit definitions for IPROC_REGCTL2 */
  40 #define IPROC_ADC_AUXIN_SCAN_ENA        BIT(0)
  41 #define IPROC_ADC_PWR_LDO               BIT(5)
  42 #define IPROC_ADC_PWR_ADC               BIT(4)
  43 #define IPROC_ADC_PWR_BG                BIT(3)
  44 #define IPROC_ADC_CONTROLLER_EN         BIT(17)
  45 
  46 /* Bit definitions for IPROC_INTERRUPT_MASK and IPROC_INTERRUPT_STATUS */
  47 #define IPROC_ADC_AUXDATA_RDY_INTR      BIT(3)
  48 #define IPROC_ADC_INTR                  9
  49 #define IPROC_ADC_INTR_MASK             (0xFF << IPROC_ADC_INTR)
  50 
  51 /* Bit definitions for IPROC_ANALOG_CONTROL */
  52 #define IPROC_ADC_CHANNEL_SEL           11
  53 #define IPROC_ADC_CHANNEL_SEL_MASK      (0x7 << IPROC_ADC_CHANNEL_SEL)
  54 
  55 /* Bit definitions for IPROC_ADC_CHANNEL_REGCTL1 */
  56 #define IPROC_ADC_CHANNEL_ROUNDS        0x2
  57 #define IPROC_ADC_CHANNEL_ROUNDS_MASK   (0x3F << IPROC_ADC_CHANNEL_ROUNDS)
  58 #define IPROC_ADC_CHANNEL_MODE          0x1
  59 #define IPROC_ADC_CHANNEL_MODE_MASK     (0x1 << IPROC_ADC_CHANNEL_MODE)
  60 #define IPROC_ADC_CHANNEL_MODE_TDM      0x1
  61 #define IPROC_ADC_CHANNEL_MODE_SNAPSHOT 0x0
  62 #define IPROC_ADC_CHANNEL_ENABLE        0x0
  63 #define IPROC_ADC_CHANNEL_ENABLE_MASK   0x1
  64 
  65 /* Bit definitions for IPROC_ADC_CHANNEL_REGCTL2 */
  66 #define IPROC_ADC_CHANNEL_WATERMARK     0x0
  67 #define IPROC_ADC_CHANNEL_WATERMARK_MASK \
  68                 (0x3F << IPROC_ADC_CHANNEL_WATERMARK)
  69 
  70 #define IPROC_ADC_WATER_MARK_LEVEL      0x1
  71 
  72 /* Bit definitions for IPROC_ADC_CHANNEL_STATUS */
  73 #define IPROC_ADC_CHANNEL_DATA_LOST             0x0
  74 #define IPROC_ADC_CHANNEL_DATA_LOST_MASK        \
  75                 (0x0 << IPROC_ADC_CHANNEL_DATA_LOST)
  76 #define IPROC_ADC_CHANNEL_VALID_ENTERIES        0x1
  77 #define IPROC_ADC_CHANNEL_VALID_ENTERIES_MASK   \
  78                 (0xFF << IPROC_ADC_CHANNEL_VALID_ENTERIES)
  79 #define IPROC_ADC_CHANNEL_TOTAL_ENTERIES        0x9
  80 #define IPROC_ADC_CHANNEL_TOTAL_ENTERIES_MASK   \
  81                 (0xFF << IPROC_ADC_CHANNEL_TOTAL_ENTERIES)
  82 
  83 /* Bit definitions for IPROC_ADC_CHANNEL_INTERRUPT_MASK */
  84 #define IPROC_ADC_CHANNEL_WTRMRK_INTR                   0x0
  85 #define IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK              \
  86                 (0x1 << IPROC_ADC_CHANNEL_WTRMRK_INTR)
  87 #define IPROC_ADC_CHANNEL_FULL_INTR                     0x1
  88 #define IPROC_ADC_CHANNEL_FULL_INTR_MASK                \
  89                 (0x1 << IPROC_ADC_IPROC_ADC_CHANNEL_FULL_INTR)
  90 #define IPROC_ADC_CHANNEL_EMPTY_INTR                    0x2
  91 #define IPROC_ADC_CHANNEL_EMPTY_INTR_MASK               \
  92                 (0x1 << IPROC_ADC_CHANNEL_EMPTY_INTR)
  93 
  94 #define IPROC_ADC_WATER_MARK_INTR_ENABLE                0x1
  95 
  96 /* Number of time to retry a set of the interrupt mask reg */
  97 #define IPROC_ADC_INTMASK_RETRY_ATTEMPTS                10
  98 
  99 #define IPROC_ADC_READ_TIMEOUT        (HZ*2)
 100 
 101 #define iproc_adc_dbg_reg(dev, priv, reg) \
 102 do { \
 103         u32 val; \
 104         regmap_read(priv->regmap, reg, &val); \
 105         dev_dbg(dev, "%20s= 0x%08x\n", #reg, val); \
 106 } while (0)
 107 
 108 struct iproc_adc_priv {
 109         struct regmap *regmap;
 110         struct clk *adc_clk;
 111         struct mutex mutex;
 112         int  irqno;
 113         int chan_val;
 114         int chan_id;
 115         struct completion completion;
 116 };
 117 
 118 static void iproc_adc_reg_dump(struct iio_dev *indio_dev)
 119 {
 120         struct device *dev = &indio_dev->dev;
 121         struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
 122 
 123         iproc_adc_dbg_reg(dev, adc_priv, IPROC_REGCTL1);
 124         iproc_adc_dbg_reg(dev, adc_priv, IPROC_REGCTL2);
 125         iproc_adc_dbg_reg(dev, adc_priv, IPROC_INTERRUPT_THRES);
 126         iproc_adc_dbg_reg(dev, adc_priv, IPROC_INTERRUPT_MASK);
 127         iproc_adc_dbg_reg(dev, adc_priv, IPROC_INTERRUPT_STATUS);
 128         iproc_adc_dbg_reg(dev, adc_priv, IPROC_CONTROLLER_STATUS);
 129         iproc_adc_dbg_reg(dev, adc_priv, IPROC_ANALOG_CONTROL);
 130         iproc_adc_dbg_reg(dev, adc_priv, IPROC_AUX_DATA);
 131         iproc_adc_dbg_reg(dev, adc_priv, IPROC_SOFT_BYPASS_CONTROL);
 132         iproc_adc_dbg_reg(dev, adc_priv, IPROC_SOFT_BYPASS_DATA);
 133 }
 134 
 135 static irqreturn_t iproc_adc_interrupt_thread(int irq, void *data)
 136 {
 137         u32 channel_intr_status;
 138         u32 intr_status;
 139         u32 intr_mask;
 140         struct iio_dev *indio_dev = data;
 141         struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
 142 
 143         /*
 144          * This interrupt is shared with the touchscreen driver.
 145          * Make sure this interrupt is intended for us.
 146          * Handle only ADC channel specific interrupts.
 147          */
 148         regmap_read(adc_priv->regmap, IPROC_INTERRUPT_STATUS, &intr_status);
 149         regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &intr_mask);
 150         intr_status = intr_status & intr_mask;
 151         channel_intr_status = (intr_status & IPROC_ADC_INTR_MASK) >>
 152                                 IPROC_ADC_INTR;
 153         if (channel_intr_status)
 154                 return IRQ_WAKE_THREAD;
 155 
 156         return IRQ_NONE;
 157 }
 158 
 159 static irqreturn_t iproc_adc_interrupt_handler(int irq, void *data)
 160 {
 161         irqreturn_t retval = IRQ_NONE;
 162         struct iproc_adc_priv *adc_priv;
 163         struct iio_dev *indio_dev = data;
 164         unsigned int valid_entries;
 165         u32 intr_status;
 166         u32 intr_channels;
 167         u32 channel_status;
 168         u32 ch_intr_status;
 169 
 170         adc_priv = iio_priv(indio_dev);
 171 
 172         regmap_read(adc_priv->regmap, IPROC_INTERRUPT_STATUS, &intr_status);
 173         dev_dbg(&indio_dev->dev, "iproc_adc_interrupt_handler(),INTRPT_STS:%x\n",
 174                         intr_status);
 175 
 176         intr_channels = (intr_status & IPROC_ADC_INTR_MASK) >> IPROC_ADC_INTR;
 177         if (intr_channels) {
 178                 regmap_read(adc_priv->regmap,
 179                             IPROC_ADC_CHANNEL_INTERRUPT_STATUS +
 180                             IPROC_ADC_CHANNEL_OFFSET * adc_priv->chan_id,
 181                             &ch_intr_status);
 182 
 183                 if (ch_intr_status & IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK) {
 184                         regmap_read(adc_priv->regmap,
 185                                         IPROC_ADC_CHANNEL_STATUS +
 186                                         IPROC_ADC_CHANNEL_OFFSET *
 187                                         adc_priv->chan_id,
 188                                         &channel_status);
 189 
 190                         valid_entries = ((channel_status &
 191                                 IPROC_ADC_CHANNEL_VALID_ENTERIES_MASK) >>
 192                                 IPROC_ADC_CHANNEL_VALID_ENTERIES);
 193                         if (valid_entries >= 1) {
 194                                 regmap_read(adc_priv->regmap,
 195                                         IPROC_ADC_CHANNEL_DATA +
 196                                         IPROC_ADC_CHANNEL_OFFSET *
 197                                         adc_priv->chan_id,
 198                                         &adc_priv->chan_val);
 199                                 complete(&adc_priv->completion);
 200                         } else {
 201                                 dev_err(&indio_dev->dev,
 202                                         "No data rcvd on channel %d\n",
 203                                         adc_priv->chan_id);
 204                         }
 205                         regmap_write(adc_priv->regmap,
 206                                         IPROC_ADC_CHANNEL_INTERRUPT_MASK +
 207                                         IPROC_ADC_CHANNEL_OFFSET *
 208                                         adc_priv->chan_id,
 209                                         (ch_intr_status &
 210                                         ~(IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK)));
 211                 }
 212                 regmap_write(adc_priv->regmap,
 213                                 IPROC_ADC_CHANNEL_INTERRUPT_STATUS +
 214                                 IPROC_ADC_CHANNEL_OFFSET * adc_priv->chan_id,
 215                                 ch_intr_status);
 216                 regmap_write(adc_priv->regmap, IPROC_INTERRUPT_STATUS,
 217                                 intr_channels);
 218                 retval = IRQ_HANDLED;
 219         }
 220 
 221         return retval;
 222 }
 223 
 224 static int iproc_adc_do_read(struct iio_dev *indio_dev,
 225                            int channel,
 226                            u16 *p_adc_data)
 227 {
 228         int read_len = 0;
 229         u32 val;
 230         u32 mask;
 231         u32 val_check;
 232         int failed_cnt = 0;
 233         struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
 234 
 235         mutex_lock(&adc_priv->mutex);
 236 
 237         /*
 238          * After a read is complete the ADC interrupts will be disabled so
 239          * we can assume this section of code is safe from interrupts.
 240          */
 241         adc_priv->chan_val = -1;
 242         adc_priv->chan_id = channel;
 243 
 244         reinit_completion(&adc_priv->completion);
 245         /* Clear any pending interrupt */
 246         regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_STATUS,
 247                         IPROC_ADC_INTR_MASK | IPROC_ADC_AUXDATA_RDY_INTR,
 248                         ((0x0 << channel) << IPROC_ADC_INTR) |
 249                         IPROC_ADC_AUXDATA_RDY_INTR);
 250 
 251         /* Configure channel for snapshot mode and enable  */
 252         val = (BIT(IPROC_ADC_CHANNEL_ROUNDS) |
 253                 (IPROC_ADC_CHANNEL_MODE_SNAPSHOT << IPROC_ADC_CHANNEL_MODE) |
 254                 (0x1 << IPROC_ADC_CHANNEL_ENABLE));
 255 
 256         mask = IPROC_ADC_CHANNEL_ROUNDS_MASK | IPROC_ADC_CHANNEL_MODE_MASK |
 257                 IPROC_ADC_CHANNEL_ENABLE_MASK;
 258         regmap_update_bits(adc_priv->regmap, (IPROC_ADC_CHANNEL_REGCTL1 +
 259                                 IPROC_ADC_CHANNEL_OFFSET * channel),
 260                                 mask, val);
 261 
 262         /* Set the Watermark for a channel */
 263         regmap_update_bits(adc_priv->regmap, (IPROC_ADC_CHANNEL_REGCTL2 +
 264                                         IPROC_ADC_CHANNEL_OFFSET * channel),
 265                                         IPROC_ADC_CHANNEL_WATERMARK_MASK,
 266                                         0x1);
 267 
 268         /* Enable water mark interrupt */
 269         regmap_update_bits(adc_priv->regmap, (IPROC_ADC_CHANNEL_INTERRUPT_MASK +
 270                                         IPROC_ADC_CHANNEL_OFFSET *
 271                                         channel),
 272                                         IPROC_ADC_CHANNEL_WTRMRK_INTR_MASK,
 273                                         IPROC_ADC_WATER_MARK_INTR_ENABLE);
 274         regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val);
 275 
 276         /* Enable ADC interrupt for a channel */
 277         val |= (BIT(channel) << IPROC_ADC_INTR);
 278         regmap_write(adc_priv->regmap, IPROC_INTERRUPT_MASK, val);
 279 
 280         /*
 281          * There seems to be a very rare issue where writing to this register
 282          * does not take effect.  To work around the issue we will try multiple
 283          * writes.  In total we will spend about 10*10 = 100 us attempting this.
 284          * Testing has shown that this may loop a few time, but we have never
 285          * hit the full count.
 286          */
 287         regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val_check);
 288         while (val_check != val) {
 289                 failed_cnt++;
 290 
 291                 if (failed_cnt > IPROC_ADC_INTMASK_RETRY_ATTEMPTS)
 292                         break;
 293 
 294                 udelay(10);
 295                 regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_MASK,
 296                                 IPROC_ADC_INTR_MASK,
 297                                 ((0x1 << channel) <<
 298                                 IPROC_ADC_INTR));
 299 
 300                 regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val_check);
 301         }
 302 
 303         if (failed_cnt) {
 304                 dev_dbg(&indio_dev->dev,
 305                         "IntMask failed (%d times)", failed_cnt);
 306                 if (failed_cnt > IPROC_ADC_INTMASK_RETRY_ATTEMPTS) {
 307                         dev_err(&indio_dev->dev,
 308                                 "IntMask set failed. Read will likely fail.");
 309                         read_len = -EIO;
 310                         goto adc_err;
 311                 };
 312         }
 313         regmap_read(adc_priv->regmap, IPROC_INTERRUPT_MASK, &val_check);
 314 
 315         if (wait_for_completion_timeout(&adc_priv->completion,
 316                 IPROC_ADC_READ_TIMEOUT) > 0) {
 317 
 318                 /* Only the lower 16 bits are relevant */
 319                 *p_adc_data = adc_priv->chan_val & 0xFFFF;
 320                 read_len = sizeof(*p_adc_data);
 321 
 322         } else {
 323                 /*
 324                  * We never got the interrupt, something went wrong.
 325                  * Perhaps the interrupt may still be coming, we do not want
 326                  * that now.  Lets disable the ADC interrupt, and clear the
 327                  * status to put it back in to normal state.
 328                  */
 329                 read_len = -ETIMEDOUT;
 330                 goto adc_err;
 331         }
 332         mutex_unlock(&adc_priv->mutex);
 333 
 334         return read_len;
 335 
 336 adc_err:
 337         regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_MASK,
 338                            IPROC_ADC_INTR_MASK,
 339                            ((0x0 << channel) << IPROC_ADC_INTR));
 340 
 341         regmap_update_bits(adc_priv->regmap, IPROC_INTERRUPT_STATUS,
 342                            IPROC_ADC_INTR_MASK,
 343                            ((0x0 << channel) << IPROC_ADC_INTR));
 344 
 345         dev_err(&indio_dev->dev, "Timed out waiting for ADC data!\n");
 346         iproc_adc_reg_dump(indio_dev);
 347         mutex_unlock(&adc_priv->mutex);
 348 
 349         return read_len;
 350 }
 351 
 352 static int iproc_adc_enable(struct iio_dev *indio_dev)
 353 {
 354         u32 val;
 355         u32 channel_id;
 356         struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
 357         int ret;
 358 
 359         /* Set i_amux = 3b'000, select channel 0 */
 360         ret = regmap_update_bits(adc_priv->regmap, IPROC_ANALOG_CONTROL,
 361                                 IPROC_ADC_CHANNEL_SEL_MASK, 0);
 362         if (ret) {
 363                 dev_err(&indio_dev->dev,
 364                         "failed to write IPROC_ANALOG_CONTROL %d\n", ret);
 365                 return ret;
 366         }
 367         adc_priv->chan_val = -1;
 368 
 369         /*
 370          * PWR up LDO, ADC, and Band Gap (0 to enable)
 371          * Also enable ADC controller (set high)
 372          */
 373         ret = regmap_read(adc_priv->regmap, IPROC_REGCTL2, &val);
 374         if (ret) {
 375                 dev_err(&indio_dev->dev,
 376                         "failed to read IPROC_REGCTL2 %d\n", ret);
 377                 return ret;
 378         }
 379 
 380         val &= ~(IPROC_ADC_PWR_LDO | IPROC_ADC_PWR_ADC | IPROC_ADC_PWR_BG);
 381 
 382         ret = regmap_write(adc_priv->regmap, IPROC_REGCTL2, val);
 383         if (ret) {
 384                 dev_err(&indio_dev->dev,
 385                         "failed to write IPROC_REGCTL2 %d\n", ret);
 386                 return ret;
 387         }
 388 
 389         ret = regmap_read(adc_priv->regmap, IPROC_REGCTL2, &val);
 390         if (ret) {
 391                 dev_err(&indio_dev->dev,
 392                         "failed to read IPROC_REGCTL2 %d\n", ret);
 393                 return ret;
 394         }
 395 
 396         val |= IPROC_ADC_CONTROLLER_EN;
 397         ret = regmap_write(adc_priv->regmap, IPROC_REGCTL2, val);
 398         if (ret) {
 399                 dev_err(&indio_dev->dev,
 400                         "failed to write IPROC_REGCTL2 %d\n", ret);
 401                 return ret;
 402         }
 403 
 404         for (channel_id = 0; channel_id < indio_dev->num_channels;
 405                 channel_id++) {
 406                 ret = regmap_write(adc_priv->regmap,
 407                                 IPROC_ADC_CHANNEL_INTERRUPT_MASK +
 408                                 IPROC_ADC_CHANNEL_OFFSET * channel_id, 0);
 409                 if (ret) {
 410                         dev_err(&indio_dev->dev,
 411                             "failed to write ADC_CHANNEL_INTERRUPT_MASK %d\n",
 412                             ret);
 413                         return ret;
 414                 }
 415 
 416                 ret = regmap_write(adc_priv->regmap,
 417                                 IPROC_ADC_CHANNEL_INTERRUPT_STATUS +
 418                                 IPROC_ADC_CHANNEL_OFFSET * channel_id, 0);
 419                 if (ret) {
 420                         dev_err(&indio_dev->dev,
 421                             "failed to write ADC_CHANNEL_INTERRUPT_STATUS %d\n",
 422                             ret);
 423                         return ret;
 424                 }
 425         }
 426 
 427         return 0;
 428 }
 429 
 430 static void iproc_adc_disable(struct iio_dev *indio_dev)
 431 {
 432         u32 val;
 433         int ret;
 434         struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
 435 
 436         ret = regmap_read(adc_priv->regmap, IPROC_REGCTL2, &val);
 437         if (ret) {
 438                 dev_err(&indio_dev->dev,
 439                         "failed to read IPROC_REGCTL2 %d\n", ret);
 440                 return;
 441         }
 442 
 443         val &= ~IPROC_ADC_CONTROLLER_EN;
 444         ret = regmap_write(adc_priv->regmap, IPROC_REGCTL2, val);
 445         if (ret) {
 446                 dev_err(&indio_dev->dev,
 447                         "failed to write IPROC_REGCTL2 %d\n", ret);
 448                 return;
 449         }
 450 }
 451 
 452 static int iproc_adc_read_raw(struct iio_dev *indio_dev,
 453                           struct iio_chan_spec const *chan,
 454                           int *val,
 455                           int *val2,
 456                           long mask)
 457 {
 458         u16 adc_data;
 459         int err;
 460 
 461         switch (mask) {
 462         case IIO_CHAN_INFO_RAW:
 463                 err =  iproc_adc_do_read(indio_dev, chan->channel, &adc_data);
 464                 if (err < 0)
 465                         return err;
 466                 *val = adc_data;
 467                 return IIO_VAL_INT;
 468         case IIO_CHAN_INFO_SCALE:
 469                 switch (chan->type) {
 470                 case IIO_VOLTAGE:
 471                         *val = 1800;
 472                         *val2 = 10;
 473                         return IIO_VAL_FRACTIONAL_LOG2;
 474                 default:
 475                         return -EINVAL;
 476                 }
 477         default:
 478                 return -EINVAL;
 479         }
 480 }
 481 
 482 static const struct iio_info iproc_adc_iio_info = {
 483         .read_raw = &iproc_adc_read_raw,
 484 };
 485 
 486 #define IPROC_ADC_CHANNEL(_index, _id) {                \
 487         .type = IIO_VOLTAGE,                            \
 488         .indexed = 1,                                   \
 489         .channel = _index,                              \
 490         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),   \
 491         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
 492         .datasheet_name = _id,                          \
 493 }
 494 
 495 static const struct iio_chan_spec iproc_adc_iio_channels[] = {
 496         IPROC_ADC_CHANNEL(0, "adc0"),
 497         IPROC_ADC_CHANNEL(1, "adc1"),
 498         IPROC_ADC_CHANNEL(2, "adc2"),
 499         IPROC_ADC_CHANNEL(3, "adc3"),
 500         IPROC_ADC_CHANNEL(4, "adc4"),
 501         IPROC_ADC_CHANNEL(5, "adc5"),
 502         IPROC_ADC_CHANNEL(6, "adc6"),
 503         IPROC_ADC_CHANNEL(7, "adc7"),
 504 };
 505 
 506 static int iproc_adc_probe(struct platform_device *pdev)
 507 {
 508         struct iproc_adc_priv *adc_priv;
 509         struct iio_dev *indio_dev = NULL;
 510         int ret;
 511 
 512         indio_dev = devm_iio_device_alloc(&pdev->dev,
 513                                         sizeof(*adc_priv));
 514         if (!indio_dev) {
 515                 dev_err(&pdev->dev, "failed to allocate iio device\n");
 516                 return -ENOMEM;
 517         }
 518 
 519         adc_priv = iio_priv(indio_dev);
 520         platform_set_drvdata(pdev, indio_dev);
 521 
 522         mutex_init(&adc_priv->mutex);
 523 
 524         init_completion(&adc_priv->completion);
 525 
 526         adc_priv->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 527                            "adc-syscon");
 528         if (IS_ERR(adc_priv->regmap)) {
 529                 dev_err(&pdev->dev, "failed to get handle for tsc syscon\n");
 530                 ret = PTR_ERR(adc_priv->regmap);
 531                 return ret;
 532         }
 533 
 534         adc_priv->adc_clk = devm_clk_get(&pdev->dev, "tsc_clk");
 535         if (IS_ERR(adc_priv->adc_clk)) {
 536                 dev_err(&pdev->dev,
 537                         "failed getting clock tsc_clk\n");
 538                 ret = PTR_ERR(adc_priv->adc_clk);
 539                 return ret;
 540         }
 541 
 542         adc_priv->irqno = platform_get_irq(pdev, 0);
 543         if (adc_priv->irqno <= 0)
 544                 return -ENODEV;
 545 
 546         ret = regmap_update_bits(adc_priv->regmap, IPROC_REGCTL2,
 547                                 IPROC_ADC_AUXIN_SCAN_ENA, 0);
 548         if (ret) {
 549                 dev_err(&pdev->dev, "failed to write IPROC_REGCTL2 %d\n", ret);
 550                 return ret;
 551         }
 552 
 553         ret = devm_request_threaded_irq(&pdev->dev, adc_priv->irqno,
 554                                 iproc_adc_interrupt_handler,
 555                                 iproc_adc_interrupt_thread,
 556                                 IRQF_SHARED, "iproc-adc", indio_dev);
 557         if (ret) {
 558                 dev_err(&pdev->dev, "request_irq error %d\n", ret);
 559                 return ret;
 560         }
 561 
 562         ret = clk_prepare_enable(adc_priv->adc_clk);
 563         if (ret) {
 564                 dev_err(&pdev->dev,
 565                         "clk_prepare_enable failed %d\n", ret);
 566                 return ret;
 567         }
 568 
 569         ret = iproc_adc_enable(indio_dev);
 570         if (ret) {
 571                 dev_err(&pdev->dev, "failed to enable adc %d\n", ret);
 572                 goto err_adc_enable;
 573         }
 574 
 575         indio_dev->name = "iproc-static-adc";
 576         indio_dev->dev.parent = &pdev->dev;
 577         indio_dev->dev.of_node = pdev->dev.of_node;
 578         indio_dev->info = &iproc_adc_iio_info;
 579         indio_dev->modes = INDIO_DIRECT_MODE;
 580         indio_dev->channels = iproc_adc_iio_channels;
 581         indio_dev->num_channels = ARRAY_SIZE(iproc_adc_iio_channels);
 582 
 583         ret = iio_device_register(indio_dev);
 584         if (ret) {
 585                 dev_err(&pdev->dev, "iio_device_register failed:err %d\n", ret);
 586                 goto err_clk;
 587         }
 588 
 589         return 0;
 590 
 591 err_clk:
 592         iproc_adc_disable(indio_dev);
 593 err_adc_enable:
 594         clk_disable_unprepare(adc_priv->adc_clk);
 595 
 596         return ret;
 597 }
 598 
 599 static int iproc_adc_remove(struct platform_device *pdev)
 600 {
 601         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 602         struct iproc_adc_priv *adc_priv = iio_priv(indio_dev);
 603 
 604         iio_device_unregister(indio_dev);
 605         iproc_adc_disable(indio_dev);
 606         clk_disable_unprepare(adc_priv->adc_clk);
 607 
 608         return 0;
 609 }
 610 
 611 static const struct of_device_id iproc_adc_of_match[] = {
 612         {.compatible = "brcm,iproc-static-adc", },
 613         { },
 614 };
 615 MODULE_DEVICE_TABLE(of, iproc_adc_of_match);
 616 
 617 static struct platform_driver iproc_adc_driver = {
 618         .probe  = iproc_adc_probe,
 619         .remove = iproc_adc_remove,
 620         .driver = {
 621                 .name   = "iproc-static-adc",
 622                 .of_match_table = of_match_ptr(iproc_adc_of_match),
 623         },
 624 };
 625 module_platform_driver(iproc_adc_driver);
 626 
 627 MODULE_DESCRIPTION("Broadcom iProc ADC controller driver");
 628 MODULE_AUTHOR("Raveendra Padasalagi <raveendra.padasalagi@broadcom.com>");
 629 MODULE_LICENSE("GPL v2");
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/iio/adc/bcm_iproc_adc.c

DEFINITIONS
