drivers/iio/adc/ad4130.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2022 Analog Devices, Inc.
   4  * Author: Cosmin Tanislav <[email protected]>
   5  */
   6
   7 #include <linux/bitfield.h>
   8 #include <linux/bitops.h>
   9 #include <linux/clk.h>
  10 #include <linux/clk-provider.h>
  11 #include <linux/delay.h>
  12 #include <linux/device.h>
  13 #include <linux/err.h>
  14 #include <linux/gpio/driver.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/irq.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/property.h>
  20 #include <linux/regmap.h>
  21 #include <linux/regulator/consumer.h>
  22 #include <linux/spi/spi.h>
  23 #include <linux/units.h>
  24
  25 #include <asm/div64.h>
  26 #include <asm/unaligned.h>
  27
  28 #include <linux/iio/buffer.h>
  29 #include <linux/iio/iio.h>
  30 #include <linux/iio/kfifo_buf.h>
  31 #include <linux/iio/sysfs.h>
  32
  33 #define AD4130_NAME                             "ad4130"
  34
  35 #define AD4130_COMMS_READ_MASK                  BIT(6)
  36
  37 #define AD4130_STATUS_REG                       0x00
  38
  39 #define AD4130_ADC_CONTROL_REG                  0x01
  40 #define AD4130_ADC_CONTROL_BIPOLAR_MASK         BIT(14)
  41 #define AD4130_ADC_CONTROL_INT_REF_VAL_MASK     BIT(13)
  42 #define AD4130_INT_REF_2_5V                     2500000
  43 #define AD4130_INT_REF_1_25V                    1250000
  44 #define AD4130_ADC_CONTROL_CSB_EN_MASK          BIT(9)
  45 #define AD4130_ADC_CONTROL_INT_REF_EN_MASK      BIT(8)
  46 #define AD4130_ADC_CONTROL_MODE_MASK            GENMASK(5, 2)
  47 #define AD4130_ADC_CONTROL_MCLK_SEL_MASK        GENMASK(1, 0)
  48 #define AD4130_MCLK_FREQ_76_8KHZ                76800
  49 #define AD4130_MCLK_FREQ_153_6KHZ               153600
  50
  51 #define AD4130_DATA_REG                         0x02
  52
  53 #define AD4130_IO_CONTROL_REG                   0x03
  54 #define AD4130_IO_CONTROL_INT_PIN_SEL_MASK      GENMASK(9, 8)
  55 #define AD4130_IO_CONTROL_GPIO_DATA_MASK        GENMASK(7, 4)
  56 #define AD4130_IO_CONTROL_GPIO_CTRL_MASK        GENMASK(3, 0)
  57
  58 #define AD4130_VBIAS_REG                        0x04
  59
  60 #define AD4130_ID_REG                           0x05
  61
  62 #define AD4130_ERROR_REG                        0x06
  63
  64 #define AD4130_ERROR_EN_REG                     0x07
  65
  66 #define AD4130_MCLK_COUNT_REG                   0x08
  67
  68 #define AD4130_CHANNEL_X_REG(x)                 (0x09 + (x))
  69 #define AD4130_CHANNEL_EN_MASK                  BIT(23)
  70 #define AD4130_CHANNEL_SETUP_MASK               GENMASK(22, 20)
  71 #define AD4130_CHANNEL_AINP_MASK                GENMASK(17, 13)
  72 #define AD4130_CHANNEL_AINM_MASK                GENMASK(12, 8)
  73 #define AD4130_CHANNEL_IOUT1_MASK               GENMASK(7, 4)
  74 #define AD4130_CHANNEL_IOUT2_MASK               GENMASK(3, 0)
  75
  76 #define AD4130_CONFIG_X_REG(x)                  (0x19 + (x))
  77 #define AD4130_CONFIG_IOUT1_VAL_MASK            GENMASK(15, 13)
  78 #define AD4130_CONFIG_IOUT2_VAL_MASK            GENMASK(12, 10)
  79 #define AD4130_CONFIG_BURNOUT_MASK              GENMASK(9, 8)
  80 #define AD4130_CONFIG_REF_BUFP_MASK             BIT(7)
  81 #define AD4130_CONFIG_REF_BUFM_MASK             BIT(6)
  82 #define AD4130_CONFIG_REF_SEL_MASK              GENMASK(5, 4)
  83 #define AD4130_CONFIG_PGA_MASK                  GENMASK(3, 1)
  84
  85 #define AD4130_FILTER_X_REG(x)                  (0x21 + (x))
  86 #define AD4130_FILTER_MODE_MASK                 GENMASK(15, 12)
  87 #define AD4130_FILTER_SELECT_MASK               GENMASK(10, 0)
  88 #define AD4130_FILTER_SELECT_MIN                1
  89
  90 #define AD4130_OFFSET_X_REG(x)                  (0x29 + (x))
  91
  92 #define AD4130_GAIN_X_REG(x)                    (0x31 + (x))
  93
  94 #define AD4130_MISC_REG                         0x39
  95
  96 #define AD4130_FIFO_CONTROL_REG                 0x3a
  97 #define AD4130_FIFO_CONTROL_HEADER_MASK         BIT(18)
  98 #define AD4130_FIFO_CONTROL_MODE_MASK           GENMASK(17, 16)
  99 #define AD4130_FIFO_CONTROL_WM_INT_EN_MASK      BIT(9)
 100 #define AD4130_FIFO_CONTROL_WM_MASK             GENMASK(7, 0)
 101 #define AD4130_WATERMARK_256                    0
 102
 103 #define AD4130_FIFO_STATUS_REG                  0x3b
 104
 105 #define AD4130_FIFO_THRESHOLD_REG               0x3c
 106
 107 #define AD4130_FIFO_DATA_REG                    0x3d
 108 #define AD4130_FIFO_SIZE                        256
 109 #define AD4130_FIFO_MAX_SAMPLE_SIZE             3
 110
 111 #define AD4130_MAX_ANALOG_PINS                  16
 112 #define AD4130_MAX_CHANNELS                     16
 113 #define AD4130_MAX_DIFF_INPUTS                  30
 114 #define AD4130_MAX_GPIOS                        4
 115 #define AD4130_MAX_ODR                          2400
 116 #define AD4130_MAX_PGA                          8
 117 #define AD4130_MAX_SETUPS                       8
 118
 119 #define AD4130_AIN2_P1                          0x2
 120 #define AD4130_AIN3_P2                          0x3
 121
 122 #define AD4130_RESET_BUF_SIZE                   8
 123 #define AD4130_RESET_SLEEP_US                   (160 * MICRO / AD4130_MCLK_FREQ_76_8KHZ)
 124
 125 #define AD4130_INVALID_SLOT                     -1
 126
 127 static const unsigned int ad4130_reg_size[] = {
 128         [AD4130_STATUS_REG] = 1,
 129         [AD4130_ADC_CONTROL_REG] = 2,
 130         [AD4130_DATA_REG] = 3,
 131         [AD4130_IO_CONTROL_REG] = 2,
 132         [AD4130_VBIAS_REG] = 2,
 133         [AD4130_ID_REG] = 1,
 134         [AD4130_ERROR_REG] = 2,
 135         [AD4130_ERROR_EN_REG] = 2,
 136         [AD4130_MCLK_COUNT_REG] = 1,
 137         [AD4130_CHANNEL_X_REG(0) ... AD4130_CHANNEL_X_REG(AD4130_MAX_CHANNELS - 1)] = 3,
 138         [AD4130_CONFIG_X_REG(0) ... AD4130_CONFIG_X_REG(AD4130_MAX_SETUPS - 1)] = 2,
 139         [AD4130_FILTER_X_REG(0) ... AD4130_FILTER_X_REG(AD4130_MAX_SETUPS - 1)] = 3,
 140         [AD4130_OFFSET_X_REG(0) ... AD4130_OFFSET_X_REG(AD4130_MAX_SETUPS - 1)] = 3,
 141         [AD4130_GAIN_X_REG(0) ... AD4130_GAIN_X_REG(AD4130_MAX_SETUPS - 1)] = 3,
 142         [AD4130_MISC_REG] = 2,
 143         [AD4130_FIFO_CONTROL_REG] = 3,
 144         [AD4130_FIFO_STATUS_REG] = 1,
 145         [AD4130_FIFO_THRESHOLD_REG] = 3,
 146         [AD4130_FIFO_DATA_REG] = 3,
 147 };
 148
 149 enum ad4130_int_ref_val {
 150         AD4130_INT_REF_VAL_2_5V,
 151         AD4130_INT_REF_VAL_1_25V,
 152 };
 153
 154 enum ad4130_mclk_sel {
 155         AD4130_MCLK_76_8KHZ,
 156         AD4130_MCLK_76_8KHZ_OUT,
 157         AD4130_MCLK_76_8KHZ_EXT,
 158         AD4130_MCLK_153_6KHZ_EXT,
 159 };
 160
 161 enum ad4130_int_pin_sel {
 162         AD4130_INT_PIN_INT,
 163         AD4130_INT_PIN_CLK,
 164         AD4130_INT_PIN_P2,
 165         AD4130_INT_PIN_DOUT,
 166 };
 167
 168 enum ad4130_iout {
 169         AD4130_IOUT_OFF,
 170         AD4130_IOUT_10000NA,
 171         AD4130_IOUT_20000NA,
 172         AD4130_IOUT_50000NA,
 173         AD4130_IOUT_100000NA,
 174         AD4130_IOUT_150000NA,
 175         AD4130_IOUT_200000NA,
 176         AD4130_IOUT_100NA,
 177         AD4130_IOUT_MAX
 178 };
 179
 180 enum ad4130_burnout {
 181         AD4130_BURNOUT_OFF,
 182         AD4130_BURNOUT_500NA,
 183         AD4130_BURNOUT_2000NA,
 184         AD4130_BURNOUT_4000NA,
 185         AD4130_BURNOUT_MAX
 186 };
 187
 188 enum ad4130_ref_sel {
 189         AD4130_REF_REFIN1,
 190         AD4130_REF_REFIN2,
 191         AD4130_REF_REFOUT_AVSS,
 192         AD4130_REF_AVDD_AVSS,
 193         AD4130_REF_SEL_MAX
 194 };
 195
 196 enum ad4130_fifo_mode {
 197         AD4130_FIFO_MODE_DISABLED = 0b00,
 198         AD4130_FIFO_MODE_WM = 0b01,
 199 };
 200
 201 enum ad4130_mode {
 202         AD4130_MODE_CONTINUOUS = 0b0000,
 203         AD4130_MODE_IDLE = 0b0100,
 204 };
 205
 206 enum ad4130_filter_mode {
 207         AD4130_FILTER_SINC4,
 208         AD4130_FILTER_SINC4_SINC1,
 209         AD4130_FILTER_SINC3,
 210         AD4130_FILTER_SINC3_REJ60,
 211         AD4130_FILTER_SINC3_SINC1,
 212         AD4130_FILTER_SINC3_PF1,
 213         AD4130_FILTER_SINC3_PF2,
 214         AD4130_FILTER_SINC3_PF3,
 215         AD4130_FILTER_SINC3_PF4,
 216 };
 217
 218 enum ad4130_pin_function {
 219         AD4130_PIN_FN_NONE,
 220         AD4130_PIN_FN_SPECIAL = BIT(0),
 221         AD4130_PIN_FN_DIFF = BIT(1),
 222         AD4130_PIN_FN_EXCITATION = BIT(2),
 223         AD4130_PIN_FN_VBIAS = BIT(3),
 224 };
 225
 226 struct ad4130_setup_info {
 227         unsigned int                    iout0_val;
 228         unsigned int                    iout1_val;
 229         unsigned int                    burnout;
 230         unsigned int                    pga;
 231         unsigned int                    fs;
 232         u32                             ref_sel;
 233         enum ad4130_filter_mode         filter_mode;
 234         bool                            ref_bufp;
 235         bool                            ref_bufm;
 236 };
 237
 238 struct ad4130_slot_info {
 239         struct ad4130_setup_info        setup;
 240         unsigned int                    enabled_channels;
 241         unsigned int                    channels;
 242 };
 243
 244 struct ad4130_chan_info {
 245         struct ad4130_setup_info        setup;
 246         u32                             iout0;
 247         u32                             iout1;
 248         int                             slot;
 249         bool                            enabled;
 250         bool                            initialized;
 251 };
 252
 253 struct ad4130_filter_config {
 254         enum ad4130_filter_mode         filter_mode;
 255         unsigned int                    odr_div;
 256         unsigned int                    fs_max;
 257         enum iio_available_type         samp_freq_avail_type;
 258         int                             samp_freq_avail_len;
 259         int                             samp_freq_avail[3][2];
 260 };
 261
 262 struct ad4130_state {
 263         struct regmap                   *regmap;
 264         struct spi_device               *spi;
 265         struct clk                      *mclk;
 266         struct regulator_bulk_data      regulators[4];
 267         u32                             irq_trigger;
 268         u32                             inv_irq_trigger;
 269
 270         /*
 271          * Synchronize access to members the of driver state, and ensure
 272          * atomicity of consecutive regmap operations.
 273          */
 274         struct mutex                    lock;
 275         struct completion               completion;
 276
 277         struct iio_chan_spec            chans[AD4130_MAX_CHANNELS];
 278         struct ad4130_chan_info         chans_info[AD4130_MAX_CHANNELS];
 279         struct ad4130_slot_info         slots_info[AD4130_MAX_SETUPS];
 280         enum ad4130_pin_function        pins_fn[AD4130_MAX_ANALOG_PINS];
 281         u32                             vbias_pins[AD4130_MAX_ANALOG_PINS];
 282         u32                             num_vbias_pins;
 283         int                             scale_tbls[AD4130_REF_SEL_MAX][AD4130_MAX_PGA][2];
 284         struct gpio_chip                gc;
 285         struct clk_hw                   int_clk_hw;
 286
 287         u32                     int_pin_sel;
 288         u32                     int_ref_uv;
 289         u32                     mclk_sel;
 290         bool                    int_ref_en;
 291         bool                    bipolar;
 292
 293         unsigned int            num_enabled_channels;
 294         unsigned int            effective_watermark;
 295         unsigned int            watermark;
 296
 297         struct spi_message      fifo_msg;
 298         struct spi_transfer     fifo_xfer[2];
 299
 300         /*
 301          * DMA (thus cache coherency maintenance) requires any transfer
 302          * buffers to live in their own cache lines. As the use of these
 303          * buffers is synchronous, all of the buffers used for DMA in this
 304          * driver may share a cache line.
 305          */
 306         u8                      reset_buf[AD4130_RESET_BUF_SIZE] __aligned(IIO_DMA_MINALIGN);
 307         u8                      reg_write_tx_buf[4];
 308         u8                      reg_read_tx_buf[1];
 309         u8                      reg_read_rx_buf[3];
 310         u8                      fifo_tx_buf[2];
 311         u8                      fifo_rx_buf[AD4130_FIFO_SIZE *
 312                                             AD4130_FIFO_MAX_SAMPLE_SIZE];
 313 };
 314
 315 static const char * const ad4130_int_pin_names[] = {
 316         [AD4130_INT_PIN_INT] = "int",
 317         [AD4130_INT_PIN_CLK] = "clk",
 318         [AD4130_INT_PIN_P2] = "p2",
 319         [AD4130_INT_PIN_DOUT] = "dout",
 320 };
 321
 322 static const unsigned int ad4130_iout_current_na_tbl[AD4130_IOUT_MAX] = {
 323         [AD4130_IOUT_OFF] = 0,
 324         [AD4130_IOUT_100NA] = 100,
 325         [AD4130_IOUT_10000NA] = 10000,
 326         [AD4130_IOUT_20000NA] = 20000,
 327         [AD4130_IOUT_50000NA] = 50000,
 328         [AD4130_IOUT_100000NA] = 100000,
 329         [AD4130_IOUT_150000NA] = 150000,
 330         [AD4130_IOUT_200000NA] = 200000,
 331 };
 332
 333 static const unsigned int ad4130_burnout_current_na_tbl[AD4130_BURNOUT_MAX] = {
 334         [AD4130_BURNOUT_OFF] = 0,
 335         [AD4130_BURNOUT_500NA] = 500,
 336         [AD4130_BURNOUT_2000NA] = 2000,
 337         [AD4130_BURNOUT_4000NA] = 4000,
 338 };
 339
 340 #define AD4130_VARIABLE_ODR_CONFIG(_filter_mode, _odr_div, _fs_max)     \
 341 {                                                                       \
 342                 .filter_mode = (_filter_mode),                          \
 343                 .odr_div = (_odr_div),                                  \
 344                 .fs_max = (_fs_max),                                    \
 345                 .samp_freq_avail_type = IIO_AVAIL_RANGE,                \
 346                 .samp_freq_avail = {                                    \
 347                         { AD4130_MAX_ODR, (_odr_div) * (_fs_max) },     \
 348                         { AD4130_MAX_ODR, (_odr_div) * (_fs_max) },     \
 349                         { AD4130_MAX_ODR, (_odr_div) },                 \
 350                 },                                                      \
 351 }
 352
 353 #define AD4130_FIXED_ODR_CONFIG(_filter_mode, _odr_div)                 \
 354 {                                                                       \
 355                 .filter_mode = (_filter_mode),                          \
 356                 .odr_div = (_odr_div),                                  \
 357                 .fs_max = AD4130_FILTER_SELECT_MIN,                     \
 358                 .samp_freq_avail_type = IIO_AVAIL_LIST,                 \
 359                 .samp_freq_avail_len = 1,                               \
 360                 .samp_freq_avail = {                                    \
 361                         { AD4130_MAX_ODR, (_odr_div) },                 \
 362                 },                                                      \
 363 }
 364
 365 static const struct ad4130_filter_config ad4130_filter_configs[] = {
 366         AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4,       1,  10),
 367         AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC4_SINC1, 11, 10),
 368         AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3,       1,  2047),
 369         AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_REJ60, 1,  2047),
 370         AD4130_VARIABLE_ODR_CONFIG(AD4130_FILTER_SINC3_SINC1, 10, 2047),
 371         AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF1,      92),
 372         AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF2,      100),
 373         AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF3,      124),
 374         AD4130_FIXED_ODR_CONFIG(AD4130_FILTER_SINC3_PF4,      148),
 375 };
 376
 377 static const char * const ad4130_filter_modes_str[] = {
 378         [AD4130_FILTER_SINC4] = "sinc4",
 379         [AD4130_FILTER_SINC4_SINC1] = "sinc4+sinc1",
 380         [AD4130_FILTER_SINC3] = "sinc3",
 381         [AD4130_FILTER_SINC3_REJ60] = "sinc3+rej60",
 382         [AD4130_FILTER_SINC3_SINC1] = "sinc3+sinc1",
 383         [AD4130_FILTER_SINC3_PF1] = "sinc3+pf1",
 384         [AD4130_FILTER_SINC3_PF2] = "sinc3+pf2",
 385         [AD4130_FILTER_SINC3_PF3] = "sinc3+pf3",
 386         [AD4130_FILTER_SINC3_PF4] = "sinc3+pf4",
 387 };
 388
 389 static int ad4130_get_reg_size(struct ad4130_state *st, unsigned int reg,
 390                                unsigned int *size)
 391 {
 392         if (reg >= ARRAY_SIZE(ad4130_reg_size))
 393                 return -EINVAL;
 394
 395         *size = ad4130_reg_size[reg];
 396
 397         return 0;
 398 }
 399
 400 static unsigned int ad4130_data_reg_size(struct ad4130_state *st)
 401 {
 402         unsigned int data_reg_size;
 403         int ret;
 404
 405         ret = ad4130_get_reg_size(st, AD4130_DATA_REG, &data_reg_size);
 406         if (ret)
 407                 return 0;
 408
 409         return data_reg_size;
 410 }
 411
 412 static unsigned int ad4130_resolution(struct ad4130_state *st)
 413 {
 414         return ad4130_data_reg_size(st) * BITS_PER_BYTE;
 415 }
 416
 417 static int ad4130_reg_write(void *context, unsigned int reg, unsigned int val)
 418 {
 419         struct ad4130_state *st = context;
 420         unsigned int size;
 421         int ret;
 422
 423         ret = ad4130_get_reg_size(st, reg, &size);
 424         if (ret)
 425                 return ret;
 426
 427         st->reg_write_tx_buf[0] = reg;
 428
 429         switch (size) {
 430         case 3:
 431                 put_unaligned_be24(val, &st->reg_write_tx_buf[1]);
 432                 break;
 433         case 2:
 434                 put_unaligned_be16(val, &st->reg_write_tx_buf[1]);
 435                 break;
 436         case 1:
 437                 st->reg_write_tx_buf[1] = val;
 438                 break;
 439         default:
 440                 return -EINVAL;
 441         }
 442
 443         return spi_write(st->spi, st->reg_write_tx_buf, size + 1);
 444 }
 445
 446 static int ad4130_reg_read(void *context, unsigned int reg, unsigned int *val)
 447 {
 448         struct ad4130_state *st = context;
 449         struct spi_transfer t[] = {
 450                 {
 451                         .tx_buf = st->reg_read_tx_buf,
 452                         .len = sizeof(st->reg_read_tx_buf),
 453                 },
 454                 {
 455                         .rx_buf = st->reg_read_rx_buf,
 456                 },
 457         };
 458         unsigned int size;
 459         int ret;
 460
 461         ret = ad4130_get_reg_size(st, reg, &size);
 462         if (ret)
 463                 return ret;
 464
 465         st->reg_read_tx_buf[0] = AD4130_COMMS_READ_MASK | reg;
 466         t[1].len = size;
 467
 468         ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t));
 469         if (ret)
 470                 return ret;
 471
 472         switch (size) {
 473         case 3:
 474                 *val = get_unaligned_be24(st->reg_read_rx_buf);
 475                 break;
 476         case 2:
 477                 *val = get_unaligned_be16(st->reg_read_rx_buf);
 478                 break;
 479         case 1:
 480                 *val = st->reg_read_rx_buf[0];
 481                 break;
 482         default:
 483                 return -EINVAL;
 484         }
 485
 486         return 0;
 487 }
 488
 489 static const struct regmap_config ad4130_regmap_config = {
 490         .reg_read = ad4130_reg_read,
 491         .reg_write = ad4130_reg_write,
 492 };
 493
 494 static int ad4130_gpio_init_valid_mask(struct gpio_chip *gc,
 495                                        unsigned long *valid_mask,
 496                                        unsigned int ngpios)
 497 {
 498         struct ad4130_state *st = gpiochip_get_data(gc);
 499         unsigned int i;
 500
 501         /*
 502          * Output-only GPIO functionality is available on pins AIN2 through
 503          * AIN5. If these pins are used for anything else, do not expose them.
 504          */
 505         for (i = 0; i < ngpios; i++) {
 506                 unsigned int pin = i + AD4130_AIN2_P1;
 507                 bool valid = st->pins_fn[pin] == AD4130_PIN_FN_NONE;
 508
 509                 __assign_bit(i, valid_mask, valid);
 510         }
 511
 512         return 0;
 513 }
 514
 515 static int ad4130_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
 516 {
 517         return GPIO_LINE_DIRECTION_OUT;
 518 }
 519
 520 static void ad4130_gpio_set(struct gpio_chip *gc, unsigned int offset,
 521                             int value)
 522 {
 523         struct ad4130_state *st = gpiochip_get_data(gc);
 524         unsigned int mask = FIELD_PREP(AD4130_IO_CONTROL_GPIO_DATA_MASK,
 525                                        BIT(offset));
 526
 527         regmap_update_bits(st->regmap, AD4130_IO_CONTROL_REG, mask,
 528                            value ? mask : 0);
 529 }
 530
 531 static int ad4130_set_mode(struct ad4130_state *st, enum ad4130_mode mode)
 532 {
 533         return regmap_update_bits(st->regmap, AD4130_ADC_CONTROL_REG,
 534                                   AD4130_ADC_CONTROL_MODE_MASK,
 535                                   FIELD_PREP(AD4130_ADC_CONTROL_MODE_MASK, mode));
 536 }
 537
 538 static int ad4130_set_watermark_interrupt_en(struct ad4130_state *st, bool en)
 539 {
 540         return regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
 541                                   AD4130_FIFO_CONTROL_WM_INT_EN_MASK,
 542                                   FIELD_PREP(AD4130_FIFO_CONTROL_WM_INT_EN_MASK, en));
 543 }
 544
 545 static unsigned int ad4130_watermark_reg_val(unsigned int val)
 546 {
 547         if (val == AD4130_FIFO_SIZE)
 548                 val = AD4130_WATERMARK_256;
 549
 550         return val;
 551 }
 552
 553 static int ad4130_set_fifo_mode(struct ad4130_state *st,
 554                                 enum ad4130_fifo_mode mode)
 555 {
 556         return regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
 557                                   AD4130_FIFO_CONTROL_MODE_MASK,
 558                                   FIELD_PREP(AD4130_FIFO_CONTROL_MODE_MASK, mode));
 559 }
 560
 561 static void ad4130_push_fifo_data(struct iio_dev *indio_dev)
 562 {
 563         struct ad4130_state *st = iio_priv(indio_dev);
 564         unsigned int data_reg_size = ad4130_data_reg_size(st);
 565         unsigned int transfer_len = st->effective_watermark * data_reg_size;
 566         unsigned int set_size = st->num_enabled_channels * data_reg_size;
 567         unsigned int i;
 568         int ret;
 569
 570         st->fifo_tx_buf[1] = ad4130_watermark_reg_val(st->effective_watermark);
 571         st->fifo_xfer[1].len = transfer_len;
 572
 573         ret = spi_sync(st->spi, &st->fifo_msg);
 574         if (ret)
 575                 return;
 576
 577         for (i = 0; i < transfer_len; i += set_size)
 578                 iio_push_to_buffers(indio_dev, &st->fifo_rx_buf[i]);
 579 }
 580
 581 static irqreturn_t ad4130_irq_handler(int irq, void *private)
 582 {
 583         struct iio_dev *indio_dev = private;
 584         struct ad4130_state *st = iio_priv(indio_dev);
 585
 586         if (iio_buffer_enabled(indio_dev))
 587                 ad4130_push_fifo_data(indio_dev);
 588         else
 589                 complete(&st->completion);
 590
 591         return IRQ_HANDLED;
 592 }
 593
 594 static int ad4130_find_slot(struct ad4130_state *st,
 595                             struct ad4130_setup_info *target_setup_info,
 596                             unsigned int *slot, bool *overwrite)
 597 {
 598         unsigned int i;
 599
 600         *slot = AD4130_INVALID_SLOT;
 601         *overwrite = false;
 602
 603         for (i = 0; i < AD4130_MAX_SETUPS; i++) {
 604                 struct ad4130_slot_info *slot_info = &st->slots_info[i];
 605
 606                 /* Immediately accept a matching setup info. */
 607                 if (!memcmp(target_setup_info, &slot_info->setup,
 608                             sizeof(*target_setup_info))) {
 609                         *slot = i;
 610                         return 0;
 611                 }
 612
 613                 /* Ignore all setups which are used by enabled channels. */
 614                 if (slot_info->enabled_channels)
 615                         continue;
 616
 617                 /* Find the least used slot. */
 618                 if (*slot == AD4130_INVALID_SLOT ||
 619                     slot_info->channels < st->slots_info[*slot].channels)
 620                         *slot = i;
 621         }
 622
 623         if (*slot == AD4130_INVALID_SLOT)
 624                 return -EINVAL;
 625
 626         *overwrite = true;
 627
 628         return 0;
 629 }
 630
 631 static void ad4130_unlink_channel(struct ad4130_state *st, unsigned int channel)
 632 {
 633         struct ad4130_chan_info *chan_info = &st->chans_info[channel];
 634         struct ad4130_slot_info *slot_info = &st->slots_info[chan_info->slot];
 635
 636         chan_info->slot = AD4130_INVALID_SLOT;
 637         slot_info->channels--;
 638 }
 639
 640 static int ad4130_unlink_slot(struct ad4130_state *st, unsigned int slot)
 641 {
 642         unsigned int i;
 643
 644         for (i = 0; i < AD4130_MAX_CHANNELS; i++) {
 645                 struct ad4130_chan_info *chan_info = &st->chans_info[i];
 646
 647                 if (!chan_info->initialized || chan_info->slot != slot)
 648                         continue;
 649
 650                 ad4130_unlink_channel(st, i);
 651         }
 652
 653         return 0;
 654 }
 655
 656 static int ad4130_link_channel_slot(struct ad4130_state *st,
 657                                     unsigned int channel, unsigned int slot)
 658 {
 659         struct ad4130_slot_info *slot_info = &st->slots_info[slot];
 660         struct ad4130_chan_info *chan_info = &st->chans_info[channel];
 661         int ret;
 662
 663         ret = regmap_update_bits(st->regmap, AD4130_CHANNEL_X_REG(channel),
 664                                  AD4130_CHANNEL_SETUP_MASK,
 665                                  FIELD_PREP(AD4130_CHANNEL_SETUP_MASK, slot));
 666         if (ret)
 667                 return ret;
 668
 669         chan_info->slot = slot;
 670         slot_info->channels++;
 671
 672         return 0;
 673 }
 674
 675 static int ad4130_write_slot_setup(struct ad4130_state *st,
 676                                    unsigned int slot,
 677                                    struct ad4130_setup_info *setup_info)
 678 {
 679         unsigned int val;
 680         int ret;
 681
 682         val = FIELD_PREP(AD4130_CONFIG_IOUT1_VAL_MASK, setup_info->iout0_val) |
 683               FIELD_PREP(AD4130_CONFIG_IOUT1_VAL_MASK, setup_info->iout1_val) |
 684               FIELD_PREP(AD4130_CONFIG_BURNOUT_MASK, setup_info->burnout) |
 685               FIELD_PREP(AD4130_CONFIG_REF_BUFP_MASK, setup_info->ref_bufp) |
 686               FIELD_PREP(AD4130_CONFIG_REF_BUFM_MASK, setup_info->ref_bufm) |
 687               FIELD_PREP(AD4130_CONFIG_REF_SEL_MASK, setup_info->ref_sel) |
 688               FIELD_PREP(AD4130_CONFIG_PGA_MASK, setup_info->pga);
 689
 690         ret = regmap_write(st->regmap, AD4130_CONFIG_X_REG(slot), val);
 691         if (ret)
 692                 return ret;
 693
 694         val = FIELD_PREP(AD4130_FILTER_MODE_MASK, setup_info->filter_mode) |
 695               FIELD_PREP(AD4130_FILTER_SELECT_MASK, setup_info->fs);
 696
 697         ret = regmap_write(st->regmap, AD4130_FILTER_X_REG(slot), val);
 698         if (ret)
 699                 return ret;
 700
 701         memcpy(&st->slots_info[slot].setup, setup_info, sizeof(*setup_info));
 702
 703         return 0;
 704 }
 705
 706 static int ad4130_write_channel_setup(struct ad4130_state *st,
 707                                       unsigned int channel, bool on_enable)
 708 {
 709         struct ad4130_chan_info *chan_info = &st->chans_info[channel];
 710         struct ad4130_setup_info *setup_info = &chan_info->setup;
 711         bool overwrite;
 712         int slot;
 713         int ret;
 714
 715         /*
 716          * The following cases need to be handled.
 717          *
 718          * 1. Enabled and linked channel with setup changes:
 719          *    - Find a slot. If not possible, return error.
 720          *    - Unlink channel from current slot.
 721          *    - If the slot has channels linked to it, unlink all channels, and
 722          *      write the new setup to it.
 723          *    - Link channel to new slot.
 724          *
 725          * 2. Soon to be enabled and unlinked channel:
 726          *    - Find a slot. If not possible, return error.
 727          *    - If the slot has channels linked to it, unlink all channels, and
 728          *      write the new setup to it.
 729          *    - Link channel to the slot.
 730          *
 731          * 3. Disabled and linked channel with setup changes:
 732          *    - Unlink channel from current slot.
 733          *
 734          * 4. Soon to be enabled and linked channel:
 735          * 5. Disabled and unlinked channel with setup changes:
 736          *    - Do nothing.
 737          */
 738
 739         /* Case 4 */
 740         if (on_enable && chan_info->slot != AD4130_INVALID_SLOT)
 741                 return 0;
 742
 743         if (!on_enable && !chan_info->enabled) {
 744                 if (chan_info->slot != AD4130_INVALID_SLOT)
 745                         /* Case 3 */
 746                         ad4130_unlink_channel(st, channel);
 747
 748                 /* Cases 3 & 5 */
 749                 return 0;
 750         }
 751
 752         /* Cases 1 & 2 */
 753         ret = ad4130_find_slot(st, setup_info, &slot, &overwrite);
 754         if (ret)
 755                 return ret;
 756
 757         if (chan_info->slot != AD4130_INVALID_SLOT)
 758                 /* Case 1 */
 759                 ad4130_unlink_channel(st, channel);
 760
 761         if (overwrite) {
 762                 ret = ad4130_unlink_slot(st, slot);
 763                 if (ret)
 764                         return ret;
 765
 766                 ret = ad4130_write_slot_setup(st, slot, setup_info);
 767                 if (ret)
 768                         return ret;
 769         }
 770
 771         return ad4130_link_channel_slot(st, channel, slot);
 772 }
 773
 774 static int ad4130_set_channel_enable(struct ad4130_state *st,
 775                                      unsigned int channel, bool status)
 776 {
 777         struct ad4130_chan_info *chan_info = &st->chans_info[channel];
 778         struct ad4130_slot_info *slot_info;
 779         int ret;
 780
 781         if (chan_info->enabled == status)
 782                 return 0;
 783
 784         if (status) {
 785                 ret = ad4130_write_channel_setup(st, channel, true);
 786                 if (ret)
 787                         return ret;
 788         }
 789
 790         slot_info = &st->slots_info[chan_info->slot];
 791
 792         ret = regmap_update_bits(st->regmap, AD4130_CHANNEL_X_REG(channel),
 793                                  AD4130_CHANNEL_EN_MASK,
 794                                  FIELD_PREP(AD4130_CHANNEL_EN_MASK, status));
 795         if (ret)
 796                 return ret;
 797
 798         slot_info->enabled_channels += status ? 1 : -1;
 799         chan_info->enabled = status;
 800
 801         return 0;
 802 }
 803
 804 /*
 805  * Table 58. FILTER_MODE_n bits and Filter Types of the datasheet describes
 806  * the relation between filter mode, ODR and FS.
 807  *
 808  * Notice that the max ODR of each filter mode is not necessarily the
 809  * absolute max ODR supported by the chip.
 810  *
 811  * The ODR divider is not explicitly specified, but it can be deduced based
 812  * on the ODR range of each filter mode.
 813  *
 814  * For example, for Sinc4+Sinc1, max ODR is 218.18. That means that the
 815  * absolute max ODR is divided by 11 to achieve the max ODR of this filter
 816  * mode.
 817  *
 818  * The formulas for converting between ODR and FS for a specific filter
 819  * mode can be deduced from the same table.
 820  *
 821  * Notice that FS = 1 actually means max ODR, and that ODR decreases by
 822  * (maximum ODR / maximum FS) for each increment of FS.
 823  *
 824  * odr = MAX_ODR / odr_div * (1 - (fs - 1) / fs_max) <=>
 825  * odr = MAX_ODR * (1 - (fs - 1) / fs_max) / odr_div <=>
 826  * odr = MAX_ODR * (1 - (fs - 1) / fs_max) / odr_div <=>
 827  * odr = MAX_ODR * (fs_max - fs + 1) / (fs_max * odr_div)
 828  * (used in ad4130_fs_to_freq)
 829  *
 830  * For the opposite formula, FS can be extracted from the last one.
 831  *
 832  * MAX_ODR * (fs_max - fs + 1) = fs_max * odr_div * odr <=>
 833  * fs_max - fs + 1 = fs_max * odr_div * odr / MAX_ODR <=>
 834  * fs = 1 + fs_max - fs_max * odr_div * odr / MAX_ODR
 835  * (used in ad4130_fs_to_freq)
 836  */
 837
 838 static void ad4130_freq_to_fs(enum ad4130_filter_mode filter_mode,
 839                               int val, int val2, unsigned int *fs)
 840 {
 841         const struct ad4130_filter_config *filter_config =
 842                 &ad4130_filter_configs[filter_mode];
 843         u64 dividend, divisor;
 844         int temp;
 845
 846         dividend = filter_config->fs_max * filter_config->odr_div *
 847                    ((u64)val * NANO + val2);
 848         divisor = (u64)AD4130_MAX_ODR * NANO;
 849
 850         temp = AD4130_FILTER_SELECT_MIN + filter_config->fs_max -
 851                DIV64_U64_ROUND_CLOSEST(dividend, divisor);
 852
 853         if (temp < AD4130_FILTER_SELECT_MIN)
 854                 temp = AD4130_FILTER_SELECT_MIN;
 855         else if (temp > filter_config->fs_max)
 856                 temp = filter_config->fs_max;
 857
 858         *fs = temp;
 859 }
 860
 861 static void ad4130_fs_to_freq(enum ad4130_filter_mode filter_mode,
 862                               unsigned int fs, int *val, int *val2)
 863 {
 864         const struct ad4130_filter_config *filter_config =
 865                 &ad4130_filter_configs[filter_mode];
 866         unsigned int dividend, divisor;
 867         u64 temp;
 868
 869         dividend = (filter_config->fs_max - fs + AD4130_FILTER_SELECT_MIN) *
 870                    AD4130_MAX_ODR;
 871         divisor = filter_config->fs_max * filter_config->odr_div;
 872
 873         temp = div_u64((u64)dividend * NANO, divisor);
 874         *val = div_u64_rem(temp, NANO, val2);
 875 }
 876
 877 static int ad4130_set_filter_mode(struct iio_dev *indio_dev,
 878                                   const struct iio_chan_spec *chan,
 879                                   unsigned int val)
 880 {
 881         struct ad4130_state *st = iio_priv(indio_dev);
 882         unsigned int channel = chan->scan_index;
 883         struct ad4130_chan_info *chan_info = &st->chans_info[channel];
 884         struct ad4130_setup_info *setup_info = &chan_info->setup;
 885         enum ad4130_filter_mode old_filter_mode;
 886         int freq_val, freq_val2;
 887         unsigned int old_fs;
 888         int ret = 0;
 889
 890         mutex_lock(&st->lock);
 891         if (setup_info->filter_mode == val)
 892                 goto out;
 893
 894         old_fs = setup_info->fs;
 895         old_filter_mode = setup_info->filter_mode;
 896
 897         /*
 898          * When switching between filter modes, try to match the ODR as
 899          * close as possible. To do this, convert the current FS into ODR
 900          * using the old filter mode, then convert it back into FS using
 901          * the new filter mode.
 902          */
 903         ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs,
 904                           &freq_val, &freq_val2);
 905
 906         ad4130_freq_to_fs(val, freq_val, freq_val2, &setup_info->fs);
 907
 908         setup_info->filter_mode = val;
 909
 910         ret = ad4130_write_channel_setup(st, channel, false);
 911         if (ret) {
 912                 setup_info->fs = old_fs;
 913                 setup_info->filter_mode = old_filter_mode;
 914         }
 915
 916  out:
 917         mutex_unlock(&st->lock);
 918
 919         return ret;
 920 }
 921
 922 static int ad4130_get_filter_mode(struct iio_dev *indio_dev,
 923                                   const struct iio_chan_spec *chan)
 924 {
 925         struct ad4130_state *st = iio_priv(indio_dev);
 926         unsigned int channel = chan->scan_index;
 927         struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
 928         enum ad4130_filter_mode filter_mode;
 929
 930         mutex_lock(&st->lock);
 931         filter_mode = setup_info->filter_mode;
 932         mutex_unlock(&st->lock);
 933
 934         return filter_mode;
 935 }
 936
 937 static const struct iio_enum ad4130_filter_mode_enum = {
 938         .items = ad4130_filter_modes_str,
 939         .num_items = ARRAY_SIZE(ad4130_filter_modes_str),
 940         .set = ad4130_set_filter_mode,
 941         .get = ad4130_get_filter_mode,
 942 };
 943
 944 static const struct iio_chan_spec_ext_info ad4130_filter_mode_ext_info[] = {
 945         IIO_ENUM("filter_mode", IIO_SEPARATE, &ad4130_filter_mode_enum),
 946         IIO_ENUM_AVAILABLE("filter_mode", IIO_SHARED_BY_TYPE,
 947                            &ad4130_filter_mode_enum),
 948         { }
 949 };
 950
 951 static const struct iio_chan_spec ad4130_channel_template = {
 952         .type = IIO_VOLTAGE,
 953         .indexed = 1,
 954         .differential = 1,
 955         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 956                               BIT(IIO_CHAN_INFO_SCALE) |
 957                               BIT(IIO_CHAN_INFO_OFFSET) |
 958                               BIT(IIO_CHAN_INFO_SAMP_FREQ),
 959         .info_mask_separate_available = BIT(IIO_CHAN_INFO_SCALE) |
 960                                         BIT(IIO_CHAN_INFO_SAMP_FREQ),
 961         .ext_info = ad4130_filter_mode_ext_info,
 962         .scan_type = {
 963                 .sign = 'u',
 964                 .endianness = IIO_BE,
 965         },
 966 };
 967
 968 static int ad4130_set_channel_pga(struct ad4130_state *st, unsigned int channel,
 969                                   int val, int val2)
 970 {
 971         struct ad4130_chan_info *chan_info = &st->chans_info[channel];
 972         struct ad4130_setup_info *setup_info = &chan_info->setup;
 973         unsigned int pga, old_pga;
 974         int ret = 0;
 975
 976         for (pga = 0; pga < AD4130_MAX_PGA; pga++)
 977                 if (val == st->scale_tbls[setup_info->ref_sel][pga][0] &&
 978                     val2 == st->scale_tbls[setup_info->ref_sel][pga][1])
 979                         break;
 980
 981         if (pga == AD4130_MAX_PGA)
 982                 return -EINVAL;
 983
 984         mutex_lock(&st->lock);
 985         if (pga == setup_info->pga)
 986                 goto out;
 987
 988         old_pga = setup_info->pga;
 989         setup_info->pga = pga;
 990
 991         ret = ad4130_write_channel_setup(st, channel, false);
 992         if (ret)
 993                 setup_info->pga = old_pga;
 994
 995 out:
 996         mutex_unlock(&st->lock);
 997
 998         return ret;
 999 }
1000
1001 static int ad4130_set_channel_freq(struct ad4130_state *st,
1002                                    unsigned int channel, int val, int val2)
1003 {
1004         struct ad4130_chan_info *chan_info = &st->chans_info[channel];
1005         struct ad4130_setup_info *setup_info = &chan_info->setup;
1006         unsigned int fs, old_fs;
1007         int ret = 0;
1008
1009         mutex_lock(&st->lock);
1010         old_fs = setup_info->fs;
1011
1012         ad4130_freq_to_fs(setup_info->filter_mode, val, val2, &fs);
1013
1014         if (fs == setup_info->fs)
1015                 goto out;
1016
1017         setup_info->fs = fs;
1018
1019         ret = ad4130_write_channel_setup(st, channel, false);
1020         if (ret)
1021                 setup_info->fs = old_fs;
1022
1023 out:
1024         mutex_unlock(&st->lock);
1025
1026         return ret;
1027 }
1028
1029 static int _ad4130_read_sample(struct iio_dev *indio_dev, unsigned int channel,
1030                                int *val)
1031 {
1032         struct ad4130_state *st = iio_priv(indio_dev);
1033         int ret;
1034
1035         ret = ad4130_set_channel_enable(st, channel, true);
1036         if (ret)
1037                 return ret;
1038
1039         reinit_completion(&st->completion);
1040
1041         ret = ad4130_set_mode(st, AD4130_MODE_CONTINUOUS);
1042         if (ret)
1043                 return ret;
1044
1045         ret = wait_for_completion_timeout(&st->completion,
1046                                           msecs_to_jiffies(1000));
1047         if (!ret)
1048                 return -ETIMEDOUT;
1049
1050         ret = ad4130_set_mode(st, AD4130_MODE_IDLE);
1051         if (ret)
1052                 return ret;
1053
1054         ret = regmap_read(st->regmap, AD4130_DATA_REG, val);
1055         if (ret)
1056                 return ret;
1057
1058         ret = ad4130_set_channel_enable(st, channel, false);
1059         if (ret)
1060                 return ret;
1061
1062         return IIO_VAL_INT;
1063 }
1064
1065 static int ad4130_read_sample(struct iio_dev *indio_dev, unsigned int channel,
1066                               int *val)
1067 {
1068         struct ad4130_state *st = iio_priv(indio_dev);
1069         int ret;
1070
1071         ret = iio_device_claim_direct_mode(indio_dev);
1072         if (ret)
1073                 return ret;
1074
1075         mutex_lock(&st->lock);
1076         ret = _ad4130_read_sample(indio_dev, channel, val);
1077         mutex_unlock(&st->lock);
1078
1079         iio_device_release_direct_mode(indio_dev);
1080
1081         return ret;
1082 }
1083
1084 static int ad4130_read_raw(struct iio_dev *indio_dev,
1085                            struct iio_chan_spec const *chan,
1086                            int *val, int *val2, long info)
1087 {
1088         struct ad4130_state *st = iio_priv(indio_dev);
1089         unsigned int channel = chan->scan_index;
1090         struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
1091
1092         switch (info) {
1093         case IIO_CHAN_INFO_RAW:
1094                 return ad4130_read_sample(indio_dev, channel, val);
1095         case IIO_CHAN_INFO_SCALE:
1096                 mutex_lock(&st->lock);
1097                 *val = st->scale_tbls[setup_info->ref_sel][setup_info->pga][0];
1098                 *val2 = st->scale_tbls[setup_info->ref_sel][setup_info->pga][1];
1099                 mutex_unlock(&st->lock);
1100
1101                 return IIO_VAL_INT_PLUS_NANO;
1102         case IIO_CHAN_INFO_OFFSET:
1103                 *val = st->bipolar ? -BIT(chan->scan_type.realbits - 1) : 0;
1104
1105                 return IIO_VAL_INT;
1106         case IIO_CHAN_INFO_SAMP_FREQ:
1107                 mutex_lock(&st->lock);
1108                 ad4130_fs_to_freq(setup_info->filter_mode, setup_info->fs,
1109                                   val, val2);
1110                 mutex_unlock(&st->lock);
1111
1112                 return IIO_VAL_INT_PLUS_NANO;
1113         default:
1114                 return -EINVAL;
1115         }
1116 }
1117
1118 static int ad4130_read_avail(struct iio_dev *indio_dev,
1119                              struct iio_chan_spec const *chan,
1120                              const int **vals, int *type, int *length,
1121                              long info)
1122 {
1123         struct ad4130_state *st = iio_priv(indio_dev);
1124         unsigned int channel = chan->scan_index;
1125         struct ad4130_setup_info *setup_info = &st->chans_info[channel].setup;
1126         const struct ad4130_filter_config *filter_config;
1127
1128         switch (info) {
1129         case IIO_CHAN_INFO_SCALE:
1130                 *vals = (int *)st->scale_tbls[setup_info->ref_sel];
1131                 *length = ARRAY_SIZE(st->scale_tbls[setup_info->ref_sel]) * 2;
1132
1133                 *type = IIO_VAL_INT_PLUS_NANO;
1134
1135                 return IIO_AVAIL_LIST;
1136         case IIO_CHAN_INFO_SAMP_FREQ:
1137                 mutex_lock(&st->lock);
1138                 filter_config = &ad4130_filter_configs[setup_info->filter_mode];
1139                 mutex_unlock(&st->lock);
1140
1141                 *vals = (int *)filter_config->samp_freq_avail;
1142                 *length = filter_config->samp_freq_avail_len * 2;
1143                 *type = IIO_VAL_FRACTIONAL;
1144
1145                 return filter_config->samp_freq_avail_type;
1146         default:
1147                 return -EINVAL;
1148         }
1149 }
1150
1151 static int ad4130_write_raw_get_fmt(struct iio_dev *indio_dev,
1152                                     struct iio_chan_spec const *chan,
1153                                     long info)
1154 {
1155         switch (info) {
1156         case IIO_CHAN_INFO_SCALE:
1157         case IIO_CHAN_INFO_SAMP_FREQ:
1158                 return IIO_VAL_INT_PLUS_NANO;
1159         default:
1160                 return -EINVAL;
1161         }
1162 }
1163
1164 static int ad4130_write_raw(struct iio_dev *indio_dev,
1165                             struct iio_chan_spec const *chan,
1166                             int val, int val2, long info)
1167 {
1168         struct ad4130_state *st = iio_priv(indio_dev);
1169         unsigned int channel = chan->scan_index;
1170
1171         switch (info) {
1172         case IIO_CHAN_INFO_SCALE:
1173                 return ad4130_set_channel_pga(st, channel, val, val2);
1174         case IIO_CHAN_INFO_SAMP_FREQ:
1175                 return ad4130_set_channel_freq(st, channel, val, val2);
1176         default:
1177                 return -EINVAL;
1178         }
1179 }
1180
1181 static int ad4130_reg_access(struct iio_dev *indio_dev, unsigned int reg,
1182                              unsigned int writeval, unsigned int *readval)
1183 {
1184         struct ad4130_state *st = iio_priv(indio_dev);
1185
1186         if (readval)
1187                 return regmap_read(st->regmap, reg, readval);
1188
1189         return regmap_write(st->regmap, reg, writeval);
1190 }
1191
1192 static int ad4130_update_scan_mode(struct iio_dev *indio_dev,
1193                                    const unsigned long *scan_mask)
1194 {
1195         struct ad4130_state *st = iio_priv(indio_dev);
1196         unsigned int channel;
1197         unsigned int val = 0;
1198         int ret;
1199
1200         mutex_lock(&st->lock);
1201
1202         for_each_set_bit(channel, scan_mask, indio_dev->num_channels) {
1203                 ret = ad4130_set_channel_enable(st, channel, true);
1204                 if (ret)
1205                         goto out;
1206
1207                 val++;
1208         }
1209
1210         st->num_enabled_channels = val;
1211
1212 out:
1213         mutex_unlock(&st->lock);
1214
1215         return 0;
1216 }
1217
1218 static int ad4130_set_fifo_watermark(struct iio_dev *indio_dev, unsigned int val)
1219 {
1220         struct ad4130_state *st = iio_priv(indio_dev);
1221         unsigned int eff;
1222         int ret;
1223
1224         if (val > AD4130_FIFO_SIZE)
1225                 return -EINVAL;
1226
1227         eff = val * st->num_enabled_channels;
1228         if (eff > AD4130_FIFO_SIZE)
1229                 /*
1230                  * Always set watermark to a multiple of the number of
1231                  * enabled channels to avoid making the FIFO unaligned.
1232                  */
1233                 eff = rounddown(AD4130_FIFO_SIZE, st->num_enabled_channels);
1234
1235         mutex_lock(&st->lock);
1236
1237         ret = regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
1238                                  AD4130_FIFO_CONTROL_WM_MASK,
1239                                  FIELD_PREP(AD4130_FIFO_CONTROL_WM_MASK,
1240                                             ad4130_watermark_reg_val(eff)));
1241         if (ret)
1242                 goto out;
1243
1244         st->effective_watermark = eff;
1245         st->watermark = val;
1246
1247 out:
1248         mutex_unlock(&st->lock);
1249
1250         return ret;
1251 }
1252
1253 static const struct iio_info ad4130_info = {
1254         .read_raw = ad4130_read_raw,
1255         .read_avail = ad4130_read_avail,
1256         .write_raw_get_fmt = ad4130_write_raw_get_fmt,
1257         .write_raw = ad4130_write_raw,
1258         .update_scan_mode = ad4130_update_scan_mode,
1259         .hwfifo_set_watermark = ad4130_set_fifo_watermark,
1260         .debugfs_reg_access = ad4130_reg_access,
1261 };
1262
1263 static int ad4130_buffer_postenable(struct iio_dev *indio_dev)
1264 {
1265         struct ad4130_state *st = iio_priv(indio_dev);
1266         int ret;
1267
1268         mutex_lock(&st->lock);
1269
1270         ret = ad4130_set_watermark_interrupt_en(st, true);
1271         if (ret)
1272                 goto out;
1273
1274         ret = irq_set_irq_type(st->spi->irq, st->inv_irq_trigger);
1275         if (ret)
1276                 goto out;
1277
1278         ret = ad4130_set_fifo_mode(st, AD4130_FIFO_MODE_WM);
1279         if (ret)
1280                 goto out;
1281
1282         ret = ad4130_set_mode(st, AD4130_MODE_CONTINUOUS);
1283
1284 out:
1285         mutex_unlock(&st->lock);
1286
1287         return ret;
1288 }
1289
1290 static int ad4130_buffer_predisable(struct iio_dev *indio_dev)
1291 {
1292         struct ad4130_state *st = iio_priv(indio_dev);
1293         unsigned int i;
1294         int ret;
1295
1296         mutex_lock(&st->lock);
1297
1298         ret = ad4130_set_mode(st, AD4130_MODE_IDLE);
1299         if (ret)
1300                 goto out;
1301
1302         ret = irq_set_irq_type(st->spi->irq, st->irq_trigger);
1303         if (ret)
1304                 goto out;
1305
1306         ret = ad4130_set_fifo_mode(st, AD4130_FIFO_MODE_DISABLED);
1307         if (ret)
1308                 goto out;
1309
1310         ret = ad4130_set_watermark_interrupt_en(st, false);
1311         if (ret)
1312                 goto out;
1313
1314         /*
1315          * update_scan_mode() is not called in the disable path, disable all
1316          * channels here.
1317          */
1318         for (i = 0; i < indio_dev->num_channels; i++) {
1319                 ret = ad4130_set_channel_enable(st, i, false);
1320                 if (ret)
1321                         goto out;
1322         }
1323
1324 out:
1325         mutex_unlock(&st->lock);
1326
1327         return ret;
1328 }
1329
1330 static const struct iio_buffer_setup_ops ad4130_buffer_ops = {
1331         .postenable = ad4130_buffer_postenable,
1332         .predisable = ad4130_buffer_predisable,
1333 };
1334
1335 static ssize_t hwfifo_watermark_show(struct device *dev,
1336                                      struct device_attribute *attr, char *buf)
1337 {
1338         struct ad4130_state *st = iio_priv(dev_to_iio_dev(dev));
1339         unsigned int val;
1340
1341         mutex_lock(&st->lock);
1342         val = st->watermark;
1343         mutex_unlock(&st->lock);
1344
1345         return sysfs_emit(buf, "%d\n", val);
1346 }
1347
1348 static ssize_t hwfifo_enabled_show(struct device *dev,
1349                                    struct device_attribute *attr, char *buf)
1350 {
1351         struct ad4130_state *st = iio_priv(dev_to_iio_dev(dev));
1352         unsigned int val;
1353         int ret;
1354
1355         ret = regmap_read(st->regmap, AD4130_FIFO_CONTROL_REG, &val);
1356         if (ret)
1357                 return ret;
1358
1359         val = FIELD_GET(AD4130_FIFO_CONTROL_MODE_MASK, val);
1360
1361         return sysfs_emit(buf, "%d\n", val != AD4130_FIFO_MODE_DISABLED);
1362 }
1363
1364 static ssize_t hwfifo_watermark_min_show(struct device *dev,
1365                                          struct device_attribute *attr,
1366                                          char *buf)
1367 {
1368         return sysfs_emit(buf, "%s\n", "1");
1369 }
1370
1371 static ssize_t hwfifo_watermark_max_show(struct device *dev,
1372                                          struct device_attribute *attr,
1373                                          char *buf)
1374 {
1375         return sysfs_emit(buf, "%s\n", __stringify(AD4130_FIFO_SIZE));
1376 }
1377
1378 static IIO_DEVICE_ATTR_RO(hwfifo_watermark_min, 0);
1379 static IIO_DEVICE_ATTR_RO(hwfifo_watermark_max, 0);
1380 static IIO_DEVICE_ATTR_RO(hwfifo_watermark, 0);
1381 static IIO_DEVICE_ATTR_RO(hwfifo_enabled, 0);
1382
1383 static const struct iio_dev_attr *ad4130_fifo_attributes[] = {
1384         &iio_dev_attr_hwfifo_watermark_min,
1385         &iio_dev_attr_hwfifo_watermark_max,
1386         &iio_dev_attr_hwfifo_watermark,
1387         &iio_dev_attr_hwfifo_enabled,
1388         NULL
1389 };
1390
1391 static int _ad4130_find_table_index(const unsigned int *tbl, size_t len,
1392                                     unsigned int val)
1393 {
1394         unsigned int i;
1395
1396         for (i = 0; i < len; i++)
1397                 if (tbl[i] == val)
1398                         return i;
1399
1400         return -EINVAL;
1401 }
1402
1403 #define ad4130_find_table_index(table, val) \
1404         _ad4130_find_table_index(table, ARRAY_SIZE(table), val)
1405
1406 static int ad4130_get_ref_voltage(struct ad4130_state *st,
1407                                   enum ad4130_ref_sel ref_sel)
1408 {
1409         switch (ref_sel) {
1410         case AD4130_REF_REFIN1:
1411                 return regulator_get_voltage(st->regulators[2].consumer);
1412         case AD4130_REF_REFIN2:
1413                 return regulator_get_voltage(st->regulators[3].consumer);
1414         case AD4130_REF_AVDD_AVSS:
1415                 return regulator_get_voltage(st->regulators[0].consumer);
1416         case AD4130_REF_REFOUT_AVSS:
1417                 return st->int_ref_uv;
1418         default:
1419                 return -EINVAL;
1420         }
1421 }
1422
1423 static int ad4130_parse_fw_setup(struct ad4130_state *st,
1424                                  struct fwnode_handle *child,
1425                                  struct ad4130_setup_info *setup_info)
1426 {
1427         struct device *dev = &st->spi->dev;
1428         u32 tmp;
1429         int ret;
1430
1431         tmp = 0;
1432         fwnode_property_read_u32(child, "adi,excitation-current-0-nanoamp", &tmp);
1433         ret = ad4130_find_table_index(ad4130_iout_current_na_tbl, tmp);
1434         if (ret < 0)
1435                 return dev_err_probe(dev, ret,
1436                                      "Invalid excitation current %unA\n", tmp);
1437         setup_info->iout0_val = ret;
1438
1439         tmp = 0;
1440         fwnode_property_read_u32(child, "adi,excitation-current-1-nanoamp", &tmp);
1441         ret = ad4130_find_table_index(ad4130_iout_current_na_tbl, tmp);
1442         if (ret < 0)
1443                 return dev_err_probe(dev, ret,
1444                                      "Invalid excitation current %unA\n", tmp);
1445         setup_info->iout1_val = ret;
1446
1447         tmp = 0;
1448         fwnode_property_read_u32(child, "adi,burnout-current-nanoamp", &tmp);
1449         ret = ad4130_find_table_index(ad4130_burnout_current_na_tbl, tmp);
1450         if (ret < 0)
1451                 return dev_err_probe(dev, ret,
1452                                      "Invalid burnout current %unA\n", tmp);
1453         setup_info->burnout = ret;
1454
1455         setup_info->ref_bufp = fwnode_property_read_bool(child, "adi,buffered-positive");
1456         setup_info->ref_bufm = fwnode_property_read_bool(child, "adi,buffered-negative");
1457
1458         setup_info->ref_sel = AD4130_REF_REFIN1;
1459         fwnode_property_read_u32(child, "adi,reference-select",
1460                                  &setup_info->ref_sel);
1461         if (setup_info->ref_sel >= AD4130_REF_SEL_MAX)
1462                 return dev_err_probe(dev, -EINVAL,
1463                                      "Invalid reference selected %u\n",
1464                                      setup_info->ref_sel);
1465
1466         if (setup_info->ref_sel == AD4130_REF_REFOUT_AVSS)
1467                 st->int_ref_en = true;
1468
1469         ret = ad4130_get_ref_voltage(st, setup_info->ref_sel);
1470         if (ret < 0)
1471                 return dev_err_probe(dev, ret, "Cannot use reference %u\n",
1472                                      setup_info->ref_sel);
1473
1474         return 0;
1475 }
1476
1477 static int ad4130_validate_diff_channel(struct ad4130_state *st, u32 pin)
1478 {
1479         struct device *dev = &st->spi->dev;
1480
1481         if (pin >= AD4130_MAX_DIFF_INPUTS)
1482                 return dev_err_probe(dev, -EINVAL,
1483                                      "Invalid differential channel %u\n", pin);
1484
1485         if (pin >= AD4130_MAX_ANALOG_PINS)
1486                 return 0;
1487
1488         if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
1489                 return dev_err_probe(dev, -EINVAL,
1490                                      "Pin %u already used with fn %u\n", pin,
1491                                      st->pins_fn[pin]);
1492
1493         st->pins_fn[pin] |= AD4130_PIN_FN_DIFF;
1494
1495         return 0;
1496 }
1497
1498 static int ad4130_validate_diff_channels(struct ad4130_state *st,
1499                                          u32 *pins, unsigned int len)
1500 {
1501         unsigned int i;
1502         int ret;
1503
1504         for (i = 0; i < len; i++) {
1505                 ret = ad4130_validate_diff_channel(st, pins[i]);
1506                 if (ret)
1507                         return ret;
1508         }
1509
1510         return 0;
1511 }
1512
1513 static int ad4130_validate_excitation_pin(struct ad4130_state *st, u32 pin)
1514 {
1515         struct device *dev = &st->spi->dev;
1516
1517         if (pin >= AD4130_MAX_ANALOG_PINS)
1518                 return dev_err_probe(dev, -EINVAL,
1519                                      "Invalid excitation pin %u\n", pin);
1520
1521         if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
1522                 return dev_err_probe(dev, -EINVAL,
1523                                      "Pin %u already used with fn %u\n", pin,
1524                                      st->pins_fn[pin]);
1525
1526         st->pins_fn[pin] |= AD4130_PIN_FN_EXCITATION;
1527
1528         return 0;
1529 }
1530
1531 static int ad4130_validate_vbias_pin(struct ad4130_state *st, u32 pin)
1532 {
1533         struct device *dev = &st->spi->dev;
1534
1535         if (pin >= AD4130_MAX_ANALOG_PINS)
1536                 return dev_err_probe(dev, -EINVAL, "Invalid vbias pin %u\n",
1537                                      pin);
1538
1539         if (st->pins_fn[pin] == AD4130_PIN_FN_SPECIAL)
1540                 return dev_err_probe(dev, -EINVAL,
1541                                      "Pin %u already used with fn %u\n", pin,
1542                                      st->pins_fn[pin]);
1543
1544         st->pins_fn[pin] |= AD4130_PIN_FN_VBIAS;
1545
1546         return 0;
1547 }
1548
1549 static int ad4130_validate_vbias_pins(struct ad4130_state *st,
1550                                       u32 *pins, unsigned int len)
1551 {
1552         unsigned int i;
1553         int ret;
1554
1555         for (i = 0; i < st->num_vbias_pins; i++) {
1556                 ret = ad4130_validate_vbias_pin(st, pins[i]);
1557                 if (ret)
1558                         return ret;
1559         }
1560
1561         return 0;
1562 }
1563
1564 static int ad4130_parse_fw_channel(struct iio_dev *indio_dev,
1565                                    struct fwnode_handle *child)
1566 {
1567         struct ad4130_state *st = iio_priv(indio_dev);
1568         unsigned int resolution = ad4130_resolution(st);
1569         unsigned int index = indio_dev->num_channels++;
1570         struct device *dev = &st->spi->dev;
1571         struct ad4130_chan_info *chan_info;
1572         struct iio_chan_spec *chan;
1573         u32 pins[2];
1574         int ret;
1575
1576         if (index >= AD4130_MAX_CHANNELS)
1577                 return dev_err_probe(dev, -EINVAL, "Too many channels\n");
1578
1579         chan = &st->chans[index];
1580         chan_info = &st->chans_info[index];
1581
1582         *chan = ad4130_channel_template;
1583         chan->scan_type.realbits = resolution;
1584         chan->scan_type.storagebits = resolution;
1585         chan->scan_index = index;
1586
1587         chan_info->slot = AD4130_INVALID_SLOT;
1588         chan_info->setup.fs = AD4130_FILTER_SELECT_MIN;
1589         chan_info->initialized = true;
1590
1591         ret = fwnode_property_read_u32_array(child, "diff-channels", pins,
1592                                              ARRAY_SIZE(pins));
1593         if (ret)
1594                 return ret;
1595
1596         ret = ad4130_validate_diff_channels(st, pins, ARRAY_SIZE(pins));
1597         if (ret)
1598                 return ret;
1599
1600         chan->channel = pins[0];
1601         chan->channel2 = pins[1];
1602
1603         ret = ad4130_parse_fw_setup(st, child, &chan_info->setup);
1604         if (ret)
1605                 return ret;
1606
1607         fwnode_property_read_u32(child, "adi,excitation-pin-0",
1608                                  &chan_info->iout0);
1609         if (chan_info->setup.iout0_val != AD4130_IOUT_OFF) {
1610                 ret = ad4130_validate_excitation_pin(st, chan_info->iout0);
1611                 if (ret)
1612                         return ret;
1613         }
1614
1615         fwnode_property_read_u32(child, "adi,excitation-pin-1",
1616                                  &chan_info->iout1);
1617         if (chan_info->setup.iout1_val != AD4130_IOUT_OFF) {
1618                 ret = ad4130_validate_excitation_pin(st, chan_info->iout1);
1619                 if (ret)
1620                         return ret;
1621         }
1622
1623         return 0;
1624 }
1625
1626 static int ad4130_parse_fw_children(struct iio_dev *indio_dev)
1627 {
1628         struct ad4130_state *st = iio_priv(indio_dev);
1629         struct device *dev = &st->spi->dev;
1630         struct fwnode_handle *child;
1631         int ret;
1632
1633         indio_dev->channels = st->chans;
1634
1635         device_for_each_child_node(dev, child) {
1636                 ret = ad4130_parse_fw_channel(indio_dev, child);
1637                 if (ret) {
1638                         fwnode_handle_put(child);
1639                         return ret;
1640                 }
1641         }
1642
1643         return 0;
1644 }
1645
1646 static int ad4310_parse_fw(struct iio_dev *indio_dev)
1647 {
1648         struct ad4130_state *st = iio_priv(indio_dev);
1649         struct device *dev = &st->spi->dev;
1650         u32 ext_clk_freq = AD4130_MCLK_FREQ_76_8KHZ;
1651         unsigned int i;
1652         int avdd_uv;
1653         int irq;
1654         int ret;
1655
1656         st->mclk = devm_clk_get_optional(dev, "mclk");
1657         if (IS_ERR(st->mclk))
1658                 return dev_err_probe(dev, PTR_ERR(st->mclk),
1659                                      "Failed to get mclk\n");
1660
1661         st->int_pin_sel = AD4130_INT_PIN_INT;
1662
1663         for (i = 0; i < ARRAY_SIZE(ad4130_int_pin_names); i++) {
1664                 irq = fwnode_irq_get_byname(dev_fwnode(dev),
1665                                             ad4130_int_pin_names[i]);
1666                 if (irq > 0) {
1667                         st->int_pin_sel = i;
1668                         break;
1669                 }
1670         }
1671
1672         if (st->int_pin_sel == AD4130_INT_PIN_DOUT)
1673                 return dev_err_probe(dev, -EINVAL,
1674                                      "Cannot use DOUT as interrupt pin\n");
1675
1676         if (st->int_pin_sel == AD4130_INT_PIN_P2)
1677                 st->pins_fn[AD4130_AIN3_P2] = AD4130_PIN_FN_SPECIAL;
1678
1679         device_property_read_u32(dev, "adi,ext-clk-freq-hz", &ext_clk_freq);
1680         if (ext_clk_freq != AD4130_MCLK_FREQ_153_6KHZ &&
1681             ext_clk_freq != AD4130_MCLK_FREQ_76_8KHZ)
1682                 return dev_err_probe(dev, -EINVAL,
1683                                      "Invalid external clock frequency %u\n",
1684                                      ext_clk_freq);
1685
1686         if (st->mclk && ext_clk_freq == AD4130_MCLK_FREQ_153_6KHZ)
1687                 st->mclk_sel = AD4130_MCLK_153_6KHZ_EXT;
1688         else if (st->mclk)
1689                 st->mclk_sel = AD4130_MCLK_76_8KHZ_EXT;
1690         else
1691                 st->mclk_sel = AD4130_MCLK_76_8KHZ;
1692
1693         if (st->int_pin_sel == AD4130_INT_PIN_CLK &&
1694             st->mclk_sel != AD4130_MCLK_76_8KHZ)
1695                 return dev_err_probe(dev, -EINVAL,
1696                                      "Invalid clock %u for interrupt pin %u\n",
1697                                      st->mclk_sel, st->int_pin_sel);
1698
1699         st->int_ref_uv = AD4130_INT_REF_2_5V;
1700
1701         /*
1702          * When the AVDD supply is set to below 2.5V the internal reference of
1703          * 1.25V should be selected.
1704          * See datasheet page 37, section ADC REFERENCE.
1705          */
1706         avdd_uv = regulator_get_voltage(st->regulators[0].consumer);
1707         if (avdd_uv > 0 && avdd_uv < AD4130_INT_REF_2_5V)
1708                 st->int_ref_uv = AD4130_INT_REF_1_25V;
1709
1710         st->bipolar = device_property_read_bool(dev, "adi,bipolar");
1711
1712         ret = device_property_count_u32(dev, "adi,vbias-pins");
1713         if (ret > 0) {
1714                 if (ret > AD4130_MAX_ANALOG_PINS)
1715                         return dev_err_probe(dev, -EINVAL,
1716                                              "Too many vbias pins %u\n", ret);
1717
1718                 st->num_vbias_pins = ret;
1719
1720                 ret = device_property_read_u32_array(dev, "adi,vbias-pins",
1721                                                      st->vbias_pins,
1722                                                      st->num_vbias_pins);
1723                 if (ret)
1724                         return dev_err_probe(dev, ret,
1725                                              "Failed to read vbias pins\n");
1726
1727                 ret = ad4130_validate_vbias_pins(st, st->vbias_pins,
1728                                                  st->num_vbias_pins);
1729                 if (ret)
1730                         return ret;
1731         }
1732
1733         ret = ad4130_parse_fw_children(indio_dev);
1734         if (ret)
1735                 return ret;
1736
1737         return 0;
1738 }
1739
1740 static void ad4130_fill_scale_tbls(struct ad4130_state *st)
1741 {
1742         unsigned int pow = ad4130_resolution(st) - st->bipolar;
1743         unsigned int i, j;
1744
1745         for (i = 0; i < AD4130_REF_SEL_MAX; i++) {
1746                 int ret;
1747                 u64 nv;
1748
1749                 ret = ad4130_get_ref_voltage(st, i);
1750                 if (ret < 0)
1751                         continue;
1752
1753                 nv = (u64)ret * NANO;
1754
1755                 for (j = 0; j < AD4130_MAX_PGA; j++)
1756                         st->scale_tbls[i][j][1] = div_u64(nv >> (pow + j), MILLI);
1757         }
1758 }
1759
1760 static void ad4130_clk_disable_unprepare(void *clk)
1761 {
1762         clk_disable_unprepare(clk);
1763 }
1764
1765 static int ad4130_set_mclk_sel(struct ad4130_state *st,
1766                                enum ad4130_mclk_sel mclk_sel)
1767 {
1768         return regmap_update_bits(st->regmap, AD4130_ADC_CONTROL_REG,
1769                                  AD4130_ADC_CONTROL_MCLK_SEL_MASK,
1770                                  FIELD_PREP(AD4130_ADC_CONTROL_MCLK_SEL_MASK,
1771                                             mclk_sel));
1772 }
1773
1774 static unsigned long ad4130_int_clk_recalc_rate(struct clk_hw *hw,
1775                                                 unsigned long parent_rate)
1776 {
1777         return AD4130_MCLK_FREQ_76_8KHZ;
1778 }
1779
1780 static int ad4130_int_clk_is_enabled(struct clk_hw *hw)
1781 {
1782         struct ad4130_state *st = container_of(hw, struct ad4130_state, int_clk_hw);
1783
1784         return st->mclk_sel == AD4130_MCLK_76_8KHZ_OUT;
1785 }
1786
1787 static int ad4130_int_clk_prepare(struct clk_hw *hw)
1788 {
1789         struct ad4130_state *st = container_of(hw, struct ad4130_state, int_clk_hw);
1790         int ret;
1791
1792         ret = ad4130_set_mclk_sel(st, AD4130_MCLK_76_8KHZ_OUT);
1793         if (ret)
1794                 return ret;
1795
1796         st->mclk_sel = AD4130_MCLK_76_8KHZ_OUT;
1797
1798         return 0;
1799 }
1800
1801 static void ad4130_int_clk_unprepare(struct clk_hw *hw)
1802 {
1803         struct ad4130_state *st = container_of(hw, struct ad4130_state, int_clk_hw);
1804         int ret;
1805
1806         ret = ad4130_set_mclk_sel(st, AD4130_MCLK_76_8KHZ);
1807         if (ret)
1808                 return;
1809
1810         st->mclk_sel = AD4130_MCLK_76_8KHZ;
1811 }
1812
1813 static const struct clk_ops ad4130_int_clk_ops = {
1814         .recalc_rate = ad4130_int_clk_recalc_rate,
1815         .is_enabled = ad4130_int_clk_is_enabled,
1816         .prepare = ad4130_int_clk_prepare,
1817         .unprepare = ad4130_int_clk_unprepare,
1818 };
1819
1820 static int ad4130_setup_int_clk(struct ad4130_state *st)
1821 {
1822         struct device *dev = &st->spi->dev;
1823         struct device_node *of_node = dev_of_node(dev);
1824         struct clk_init_data init;
1825         const char *clk_name;
1826         struct clk *clk;
1827
1828         if (st->int_pin_sel == AD4130_INT_PIN_CLK ||
1829             st->mclk_sel != AD4130_MCLK_76_8KHZ)
1830                 return 0;
1831
1832         if (!of_node)
1833                 return 0;
1834
1835         clk_name = of_node->name;
1836         of_property_read_string(of_node, "clock-output-names", &clk_name);
1837
1838         init.name = clk_name;
1839         init.ops = &ad4130_int_clk_ops;
1840
1841         st->int_clk_hw.init = &init;
1842         clk = devm_clk_register(dev, &st->int_clk_hw);
1843         if (IS_ERR(clk))
1844                 return PTR_ERR(clk);
1845
1846         return of_clk_add_provider(of_node, of_clk_src_simple_get, clk);
1847 }
1848
1849 static int ad4130_setup(struct iio_dev *indio_dev)
1850 {
1851         struct ad4130_state *st = iio_priv(indio_dev);
1852         struct device *dev = &st->spi->dev;
1853         unsigned int int_ref_val;
1854         unsigned long rate = AD4130_MCLK_FREQ_76_8KHZ;
1855         unsigned int val;
1856         unsigned int i;
1857         int ret;
1858
1859         if (st->mclk_sel == AD4130_MCLK_153_6KHZ_EXT)
1860                 rate = AD4130_MCLK_FREQ_153_6KHZ;
1861
1862         ret = clk_set_rate(st->mclk, rate);
1863         if (ret)
1864                 return ret;
1865
1866         ret = clk_prepare_enable(st->mclk);
1867         if (ret)
1868                 return ret;
1869
1870         ret = devm_add_action_or_reset(dev, ad4130_clk_disable_unprepare,
1871                                        st->mclk);
1872         if (ret)
1873                 return ret;
1874
1875         if (st->int_ref_uv == AD4130_INT_REF_2_5V)
1876                 int_ref_val = AD4130_INT_REF_VAL_2_5V;
1877         else
1878                 int_ref_val = AD4130_INT_REF_VAL_1_25V;
1879
1880         /* Switch to SPI 4-wire mode. */
1881         val =  FIELD_PREP(AD4130_ADC_CONTROL_CSB_EN_MASK, 1);
1882         val |= FIELD_PREP(AD4130_ADC_CONTROL_BIPOLAR_MASK, st->bipolar);
1883         val |= FIELD_PREP(AD4130_ADC_CONTROL_INT_REF_EN_MASK, st->int_ref_en);
1884         val |= FIELD_PREP(AD4130_ADC_CONTROL_MODE_MASK, AD4130_MODE_IDLE);
1885         val |= FIELD_PREP(AD4130_ADC_CONTROL_MCLK_SEL_MASK, st->mclk_sel);
1886         val |= FIELD_PREP(AD4130_ADC_CONTROL_INT_REF_VAL_MASK, int_ref_val);
1887
1888         ret = regmap_write(st->regmap, AD4130_ADC_CONTROL_REG, val);
1889         if (ret)
1890                 return ret;
1891
1892         /*
1893          * Configure all GPIOs for output. If configured, the interrupt function
1894          * of P2 takes priority over the GPIO out function.
1895          */
1896         val =  AD4130_IO_CONTROL_GPIO_CTRL_MASK;
1897         val |= FIELD_PREP(AD4130_IO_CONTROL_INT_PIN_SEL_MASK, st->int_pin_sel);
1898
1899         ret = regmap_write(st->regmap, AD4130_IO_CONTROL_REG, val);
1900         if (ret)
1901                 return ret;
1902
1903         val = 0;
1904         for (i = 0; i < st->num_vbias_pins; i++)
1905                 val |= BIT(st->vbias_pins[i]);
1906
1907         ret = regmap_write(st->regmap, AD4130_VBIAS_REG, val);
1908         if (ret)
1909                 return ret;
1910
1911         ret = regmap_update_bits(st->regmap, AD4130_FIFO_CONTROL_REG,
1912                                  AD4130_FIFO_CONTROL_HEADER_MASK, 0);
1913         if (ret)
1914                 return ret;
1915
1916         /* FIFO watermark interrupt starts out as enabled, disable it. */
1917         ret = ad4130_set_watermark_interrupt_en(st, false);
1918         if (ret)
1919                 return ret;
1920
1921         /* Setup channels. */
1922         for (i = 0; i < indio_dev->num_channels; i++) {
1923                 struct ad4130_chan_info *chan_info = &st->chans_info[i];
1924                 struct iio_chan_spec *chan = &st->chans[i];
1925                 unsigned int val;
1926
1927                 val = FIELD_PREP(AD4130_CHANNEL_AINP_MASK, chan->channel) |
1928                       FIELD_PREP(AD4130_CHANNEL_AINM_MASK, chan->channel2) |
1929                       FIELD_PREP(AD4130_CHANNEL_IOUT1_MASK, chan_info->iout0) |
1930                       FIELD_PREP(AD4130_CHANNEL_IOUT2_MASK, chan_info->iout1);
1931
1932                 ret = regmap_write(st->regmap, AD4130_CHANNEL_X_REG(i), val);
1933                 if (ret)
1934                         return ret;
1935         }
1936
1937         return 0;
1938 }
1939
1940 static int ad4130_soft_reset(struct ad4130_state *st)
1941 {
1942         int ret;
1943
1944         ret = spi_write(st->spi, st->reset_buf, sizeof(st->reset_buf));
1945         if (ret)
1946                 return ret;
1947
1948         fsleep(AD4130_RESET_SLEEP_US);
1949
1950         return 0;
1951 }
1952
1953 static void ad4130_disable_regulators(void *data)
1954 {
1955         struct ad4130_state *st = data;
1956
1957         regulator_bulk_disable(ARRAY_SIZE(st->regulators), st->regulators);
1958 }
1959
1960 static int ad4130_probe(struct spi_device *spi)
1961 {
1962         struct device *dev = &spi->dev;
1963         struct iio_dev *indio_dev;
1964         struct ad4130_state *st;
1965         int ret;
1966
1967         indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
1968         if (!indio_dev)
1969                 return -ENOMEM;
1970
1971         st = iio_priv(indio_dev);
1972
1973         memset(st->reset_buf, 0xff, sizeof(st->reset_buf));
1974         init_completion(&st->completion);
1975         mutex_init(&st->lock);
1976         st->spi = spi;
1977
1978         /*
1979          * Xfer:   [ XFR1 ] [         XFR2         ]
1980          * Master:  0x7D N   ......................
1981          * Slave:   ......   DATA1 DATA2 ... DATAN
1982          */
1983         st->fifo_tx_buf[0] = AD4130_COMMS_READ_MASK | AD4130_FIFO_DATA_REG;
1984         st->fifo_xfer[0].tx_buf = st->fifo_tx_buf;
1985         st->fifo_xfer[0].len = sizeof(st->fifo_tx_buf);
1986         st->fifo_xfer[1].rx_buf = st->fifo_rx_buf;
1987         spi_message_init_with_transfers(&st->fifo_msg, st->fifo_xfer,
1988                                         ARRAY_SIZE(st->fifo_xfer));
1989
1990         indio_dev->name = AD4130_NAME;
1991         indio_dev->modes = INDIO_DIRECT_MODE;
1992         indio_dev->info = &ad4130_info;
1993
1994         st->regmap = devm_regmap_init(dev, NULL, st, &ad4130_regmap_config);
1995         if (IS_ERR(st->regmap))
1996                 return PTR_ERR(st->regmap);
1997
1998         st->regulators[0].supply = "avdd";
1999         st->regulators[1].supply = "iovdd";
2000         st->regulators[2].supply = "refin1";
2001         st->regulators[3].supply = "refin2";
2002
2003         ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(st->regulators),
2004                                       st->regulators);
2005         if (ret)
2006                 return dev_err_probe(dev, ret, "Failed to get regulators\n");
2007
2008         ret = regulator_bulk_enable(ARRAY_SIZE(st->regulators), st->regulators);
2009         if (ret)
2010                 return dev_err_probe(dev, ret, "Failed to enable regulators\n");
2011
2012         ret = devm_add_action_or_reset(dev, ad4130_disable_regulators, st);
2013         if (ret)
2014                 return dev_err_probe(dev, ret,
2015                                      "Failed to add regulators disable action\n");
2016
2017         ret = ad4130_soft_reset(st);
2018         if (ret)
2019                 return ret;
2020
2021         ret = ad4310_parse_fw(indio_dev);
2022         if (ret)
2023                 return ret;
2024
2025         ret = ad4130_setup(indio_dev);
2026         if (ret)
2027                 return ret;
2028
2029         ret = ad4130_setup_int_clk(st);
2030         if (ret)
2031                 return ret;
2032
2033         ad4130_fill_scale_tbls(st);
2034
2035         st->gc.owner = THIS_MODULE;
2036         st->gc.label = AD4130_NAME;
2037         st->gc.base = -1;
2038         st->gc.ngpio = AD4130_MAX_GPIOS;
2039         st->gc.parent = dev;
2040         st->gc.can_sleep = true;
2041         st->gc.init_valid_mask = ad4130_gpio_init_valid_mask;
2042         st->gc.get_direction = ad4130_gpio_get_direction;
2043         st->gc.set = ad4130_gpio_set;
2044
2045         ret = devm_gpiochip_add_data(dev, &st->gc, st);
2046         if (ret)
2047                 return ret;
2048
2049         ret = devm_iio_kfifo_buffer_setup_ext(dev, indio_dev,
2050                                               &ad4130_buffer_ops,
2051                                               ad4130_fifo_attributes);
2052         if (ret)
2053                 return ret;
2054
2055         ret = devm_request_threaded_irq(dev, spi->irq, NULL,
2056                                         ad4130_irq_handler, IRQF_ONESHOT,
2057                                         indio_dev->name, indio_dev);
2058         if (ret)
2059                 return dev_err_probe(dev, ret, "Failed to request irq\n");
2060
2061         /*
2062          * When the chip enters FIFO mode, IRQ polarity is inverted.
2063          * When the chip exits FIFO mode, IRQ polarity returns to normal.
2064          * See datasheet pages: 65, FIFO Watermark Interrupt section,
2065          * and 71, Bit Descriptions for STATUS Register, RDYB.
2066          * Cache the normal and inverted IRQ triggers to set them when
2067          * entering and exiting FIFO mode.
2068          */
2069         st->irq_trigger = irq_get_trigger_type(spi->irq);
2070         if (st->irq_trigger & IRQF_TRIGGER_RISING)
2071                 st->inv_irq_trigger = IRQF_TRIGGER_FALLING;
2072         else if (st->irq_trigger & IRQF_TRIGGER_FALLING)
2073                 st->inv_irq_trigger = IRQF_TRIGGER_RISING;
2074         else
2075                 return dev_err_probe(dev, -EINVAL, "Invalid irq flags: %u\n",
2076                                      st->irq_trigger);
2077
2078         return devm_iio_device_register(dev, indio_dev);
2079 }
2080
2081 static const struct of_device_id ad4130_of_match[] = {
2082         {
2083                 .compatible = "adi,ad4130",
2084         },
2085         { }
2086 };
2087 MODULE_DEVICE_TABLE(of, ad4130_of_match);
2088
2089 static struct spi_driver ad4130_driver = {
2090         .driver = {
2091                 .name = AD4130_NAME,
2092                 .of_match_table = ad4130_of_match,
2093         },
2094         .probe = ad4130_probe,
2095 };
2096 module_spi_driver(ad4130_driver);
2097
2098 MODULE_AUTHOR("Cosmin Tanislav <[email protected]>");
2099 MODULE_DESCRIPTION("Analog Devices AD4130 SPI driver");
2100 MODULE_LICENSE("GPL");