- 根目录:
- drivers
- iio
- dac
- ad5791.c
#include <linux/interrupt.h>
#include <linux/fs.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/regulator/consumer.h>
#include <linux/module.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/dac/ad5791.h>
#define AD5791_RES_MASK(x) ((1 << (x)) - 1)
#define AD5791_DAC_MASK AD5791_RES_MASK(20)
#define AD5791_DAC_MSB (1 << 19)
#define AD5791_CMD_READ (1 << 23)
#define AD5791_CMD_WRITE (0 << 23)
#define AD5791_ADDR(addr) ((addr) << 20)
#define AD5791_ADDR_NOOP 0
#define AD5791_ADDR_DAC0 1
#define AD5791_ADDR_CTRL 2
#define AD5791_ADDR_CLRCODE 3
#define AD5791_ADDR_SW_CTRL 4
#define AD5791_CTRL_RBUF (1 << 1)
#define AD5791_CTRL_OPGND (1 << 2)
#define AD5791_CTRL_DACTRI (1 << 3)
#define AD5791_CTRL_BIN2SC (1 << 4)
#define AD5791_CTRL_SDODIS (1 << 5)
#define AD5761_CTRL_LINCOMP(x) ((x) << 6)
#define AD5791_LINCOMP_0_10 0
#define AD5791_LINCOMP_10_12 1
#define AD5791_LINCOMP_12_16 2
#define AD5791_LINCOMP_16_19 3
#define AD5791_LINCOMP_19_20 12
#define AD5780_LINCOMP_0_10 0
#define AD5780_LINCOMP_10_20 12
#define AD5791_SWCTRL_LDAC (1 << 0)
#define AD5791_SWCTRL_CLR (1 << 1)
#define AD5791_SWCTRL_RESET (1 << 2)
#define AD5791_DAC_PWRDN_6K 0
#define AD5791_DAC_PWRDN_3STATE 1
struct ad5791_chip_info {
int (*get_lin_comp) (unsigned int span);
};
struct ad5791_state {
struct spi_device *spi;
struct regulator *reg_vdd;
struct regulator *reg_vss;
const struct ad5791_chip_info *chip_info;
unsigned short vref_mv;
unsigned int vref_neg_mv;
unsigned ctrl;
unsigned pwr_down_mode;
bool pwr_down;
union {
__be32 d32;
u8 d8[4];
} data[3] ____cacheline_aligned;
};
enum ad5791_supported_device_ids {
ID_AD5760,
ID_AD5780,
ID_AD5781,
ID_AD5791,
};
static int ad5791_spi_write(struct ad5791_state *st, u8 addr, u32 val)
{
st->data[0].d32 = cpu_to_be32(AD5791_CMD_WRITE |
AD5791_ADDR(addr) |
(val & AD5791_DAC_MASK));
return spi_write(st->spi, &st->data[0].d8[1], 3);
}
static int ad5791_spi_read(struct ad5791_state *st, u8 addr, u32 *val)
{
int ret;
struct spi_transfer xfers[] = {
{
.tx_buf = &st->data[0].d8[1],
.bits_per_word = 8,
.len = 3,
.cs_change = 1,
}, {
.tx_buf = &st->data[1].d8[1],
.rx_buf = &st->data[2].d8[1],
.bits_per_word = 8,
.len = 3,
},
};
st->data[0].d32 = cpu_to_be32(AD5791_CMD_READ |
AD5791_ADDR(addr));
st->data[1].d32 = cpu_to_be32(AD5791_ADDR(AD5791_ADDR_NOOP));
ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));
*val = be32_to_cpu(st->data[2].d32);
return ret;
}
static const char * const ad5791_powerdown_modes[] = {
"6kohm_to_gnd",
"three_state",
};
static int ad5791_get_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct ad5791_state *st = iio_priv(indio_dev);
return st->pwr_down_mode;
}
static int ad5791_set_powerdown_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan, unsigned int mode)
{
struct ad5791_state *st = iio_priv(indio_dev);
st->pwr_down_mode = mode;
return 0;
}
static const struct iio_enum ad5791_powerdown_mode_enum = {
.items = ad5791_powerdown_modes,
.num_items = ARRAY_SIZE(ad5791_powerdown_modes),
.get = ad5791_get_powerdown_mode,
.set = ad5791_set_powerdown_mode,
};
static ssize_t ad5791_read_dac_powerdown(struct iio_dev *indio_dev,
uintptr_t private, const struct iio_chan_spec *chan, char *buf)
{
struct ad5791_state *st = iio_priv(indio_dev);
return sprintf(buf, "%d\n", st->pwr_down);
}
static ssize_t ad5791_write_dac_powerdown(struct iio_dev *indio_dev,
uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
size_t len)
{
bool pwr_down;
int ret;
struct ad5791_state *st = iio_priv(indio_dev);
ret = strtobool(buf, &pwr_down);
if (ret)
return ret;
if (!pwr_down) {
st->ctrl &= ~(AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI);
} else {
if (st->pwr_down_mode == AD5791_DAC_PWRDN_6K)
st->ctrl |= AD5791_CTRL_OPGND;
else if (st->pwr_down_mode == AD5791_DAC_PWRDN_3STATE)
st->ctrl |= AD5791_CTRL_DACTRI;
}
st->pwr_down = pwr_down;
ret = ad5791_spi_write(st, AD5791_ADDR_CTRL, st->ctrl);
return ret ? ret : len;
}
static int ad5791_get_lin_comp(unsigned int span)
{
if (span <= 10000)
return AD5791_LINCOMP_0_10;
else if (span <= 12000)
return AD5791_LINCOMP_10_12;
else if (span <= 16000)
return AD5791_LINCOMP_12_16;
else if (span <= 19000)
return AD5791_LINCOMP_16_19;
else
return AD5791_LINCOMP_19_20;
}
static int ad5780_get_lin_comp(unsigned int span)
{
if (span <= 10000)
return AD5780_LINCOMP_0_10;
else
return AD5780_LINCOMP_10_20;
}
static const struct ad5791_chip_info ad5791_chip_info_tbl[] = {
[ID_AD5760] = {
.get_lin_comp = ad5780_get_lin_comp,
},
[ID_AD5780] = {
.get_lin_comp = ad5780_get_lin_comp,
},
[ID_AD5781] = {
.get_lin_comp = ad5791_get_lin_comp,
},
[ID_AD5791] = {
.get_lin_comp = ad5791_get_lin_comp,
},
};
static int ad5791_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long m)
{
struct ad5791_state *st = iio_priv(indio_dev);
u64 val64;
int ret;
switch (m) {
case IIO_CHAN_INFO_RAW:
ret = ad5791_spi_read(st, chan->address, val);
if (ret)
return ret;
*val &= AD5791_DAC_MASK;
*val >>= chan->scan_type.shift;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
*val = st->vref_mv;
*val2 = (1 << chan->scan_type.realbits) - 1;
return IIO_VAL_FRACTIONAL;
case IIO_CHAN_INFO_OFFSET:
val64 = (((u64)st->vref_neg_mv) << chan->scan_type.realbits);
do_div(val64, st->vref_mv);
*val = -val64;
return IIO_VAL_INT;
default:
return -EINVAL;
}
};
static const struct iio_chan_spec_ext_info ad5791_ext_info[] = {
{
.name = "powerdown",
.shared = IIO_SHARED_BY_TYPE,
.read = ad5791_read_dac_powerdown,
.write = ad5791_write_dac_powerdown,
},
IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
&ad5791_powerdown_mode_enum),
IIO_ENUM_AVAILABLE("powerdown_mode", &ad5791_powerdown_mode_enum),
{ },
};
#define AD5791_CHAN(bits, _shift) { \
.type = IIO_VOLTAGE, \
.output = 1, \
.indexed = 1, \
.address = AD5791_ADDR_DAC0, \
.channel = 0, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_OFFSET), \
.scan_type = { \
.sign = 'u', \
.realbits = (bits), \
.storagebits = 24, \
.shift = (_shift), \
}, \
.ext_info = ad5791_ext_info, \
}
static const struct iio_chan_spec ad5791_channels[] = {
[ID_AD5760] = AD5791_CHAN(16, 4),
[ID_AD5780] = AD5791_CHAN(18, 2),
[ID_AD5781] = AD5791_CHAN(18, 2),
[ID_AD5791] = AD5791_CHAN(20, 0)
};
static int ad5791_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val,
int val2,
long mask)
{
struct ad5791_state *st = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_RAW:
val &= AD5791_RES_MASK(chan->scan_type.realbits);
val <<= chan->scan_type.shift;
return ad5791_spi_write(st, chan->address, val);
default:
return -EINVAL;
}
}
static const struct iio_info ad5791_info = {
.read_raw = &ad5791_read_raw,
.write_raw = &ad5791_write_raw,
.driver_module = THIS_MODULE,
};
static int ad5791_probe(struct spi_device *spi)
{
struct ad5791_platform_data *pdata = spi->dev.platform_data;
struct iio_dev *indio_dev;
struct ad5791_state *st;
int ret, pos_voltage_uv = 0, neg_voltage_uv = 0;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
st = iio_priv(indio_dev);
st->reg_vdd = devm_regulator_get(&spi->dev, "vdd");
if (!IS_ERR(st->reg_vdd)) {
ret = regulator_enable(st->reg_vdd);
if (ret)
return ret;
ret = regulator_get_voltage(st->reg_vdd);
if (ret < 0)
goto error_disable_reg_pos;
pos_voltage_uv = ret;
}
st->reg_vss = devm_regulator_get(&spi->dev, "vss");
if (!IS_ERR(st->reg_vss)) {
ret = regulator_enable(st->reg_vss);
if (ret)
goto error_disable_reg_pos;
ret = regulator_get_voltage(st->reg_vss);
if (ret < 0)
goto error_disable_reg_neg;
neg_voltage_uv = ret;
}
st->pwr_down = true;
st->spi = spi;
if (!IS_ERR(st->reg_vss) && !IS_ERR(st->reg_vdd)) {
st->vref_mv = (pos_voltage_uv + neg_voltage_uv) / 1000;
st->vref_neg_mv = neg_voltage_uv / 1000;
} else if (pdata) {
st->vref_mv = pdata->vref_pos_mv + pdata->vref_neg_mv;
st->vref_neg_mv = pdata->vref_neg_mv;
} else {
dev_warn(&spi->dev, "reference voltage unspecified\n");
}
ret = ad5791_spi_write(st, AD5791_ADDR_SW_CTRL, AD5791_SWCTRL_RESET);
if (ret)
goto error_disable_reg_neg;
st->chip_info = &ad5791_chip_info_tbl[spi_get_device_id(spi)
->driver_data];
st->ctrl = AD5761_CTRL_LINCOMP(st->chip_info->get_lin_comp(st->vref_mv))
| ((pdata && pdata->use_rbuf_gain2) ? 0 : AD5791_CTRL_RBUF) |
AD5791_CTRL_BIN2SC;
ret = ad5791_spi_write(st, AD5791_ADDR_CTRL, st->ctrl |
AD5791_CTRL_OPGND | AD5791_CTRL_DACTRI);
if (ret)
goto error_disable_reg_neg;
spi_set_drvdata(spi, indio_dev);
indio_dev->dev.parent = &spi->dev;
indio_dev->info = &ad5791_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels
= &ad5791_channels[spi_get_device_id(spi)->driver_data];
indio_dev->num_channels = 1;
indio_dev->name = spi_get_device_id(st->spi)->name;
ret = iio_device_register(indio_dev);
if (ret)
goto error_disable_reg_neg;
return 0;
error_disable_reg_neg:
if (!IS_ERR(st->reg_vss))
regulator_disable(st->reg_vss);
error_disable_reg_pos:
if (!IS_ERR(st->reg_vdd))
regulator_disable(st->reg_vdd);
return ret;
}
static int ad5791_remove(struct spi_device *spi)
{
struct iio_dev *indio_dev = spi_get_drvdata(spi);
struct ad5791_state *st = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
if (!IS_ERR(st->reg_vdd))
regulator_disable(st->reg_vdd);
if (!IS_ERR(st->reg_vss))
regulator_disable(st->reg_vss);
return 0;
}
static const struct spi_device_id ad5791_id[] = {
{"ad5760", ID_AD5760},
{"ad5780", ID_AD5780},
{"ad5781", ID_AD5781},
{"ad5790", ID_AD5791},
{"ad5791", ID_AD5791},
{}
};
MODULE_DEVICE_TABLE(spi, ad5791_id);
static struct spi_driver ad5791_driver = {
.driver = {
.name = "ad5791",
.owner = THIS_MODULE,
},
.probe = ad5791_probe,
.remove = ad5791_remove,
.id_table = ad5791_id,
};
module_spi_driver(ad5791_driver);
MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("Analog Devices AD5760/AD5780/AD5781/AD5790/AD5791 DAC");
MODULE_LICENSE("GPL v2");
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
- 17
- 18
- 19
- 20
- 21
- 22
- 23
- 24
- 25
- 26
- 27
- 28
- 29
- 30
- 31
- 32
- 33
- 34
- 35
- 36
- 37
- 38
- 39
- 40
- 41
- 42
- 43
- 44
- 45
- 46
- 47
- 48
- 49
- 50
- 51
- 52
- 53
- 54
- 55
- 56
- 57
- 58
- 59
- 60
- 61
- 62
- 63
- 64
- 65
- 66
- 67
- 68
- 69
- 70
- 71
- 72
- 73
- 74
- 75
- 76
- 77
- 78
- 79
- 80
- 81
- 82
- 83
- 84
- 85
- 86
- 87
- 88
- 89
- 90
- 91
- 92
- 93
- 94
- 95
- 96
- 97
- 98
- 99
- 100
- 101
- 102
- 103
- 104
- 105
- 106
- 107
- 108
- 109
- 110
- 111
- 112
- 113
- 114
- 115
- 116
- 117
- 118
- 119
- 120
- 121
- 122
- 123
- 124
- 125
- 126
- 127
- 128
- 129
- 130
- 131
- 132
- 133
- 134
- 135
- 136
- 137
- 138
- 139
- 140
- 141
- 142
- 143
- 144
- 145
- 146
- 147
- 148
- 149
- 150
- 151
- 152
- 153
- 154
- 155
- 156
- 157
- 158
- 159
- 160
- 161
- 162
- 163
- 164
- 165
- 166
- 167
- 168
- 169
- 170
- 171
- 172
- 173
- 174
- 175
- 176
- 177
- 178
- 179
- 180
- 181
- 182
- 183
- 184
- 185
- 186
- 187
- 188
- 189
- 190
- 191
- 192
- 193
- 194
- 195
- 196
- 197
- 198
- 199
- 200
- 201
- 202
- 203
- 204
- 205
- 206
- 207
- 208
- 209
- 210
- 211
- 212
- 213
- 214
- 215
- 216
- 217
- 218
- 219
- 220
- 221
- 222
- 223
- 224
- 225
- 226
- 227
- 228
- 229
- 230
- 231
- 232
- 233
- 234
- 235
- 236
- 237
- 238
- 239
- 240
- 241
- 242
- 243
- 244
- 245
- 246
- 247
- 248
- 249
- 250
- 251
- 252
- 253
- 254
- 255
- 256
- 257
- 258
- 259
- 260
- 261
- 262
- 263
- 264
- 265
- 266
- 267
- 268
- 269
- 270
- 271
- 272
- 273
- 274
- 275
- 276
- 277
- 278
- 279
- 280
- 281
- 282
- 283
- 284
- 285
- 286
- 287
- 288
- 289
- 290
- 291
- 292
- 293
- 294
- 295
- 296
- 297
- 298
- 299
- 300
- 301
- 302
- 303
- 304
- 305
- 306
- 307
- 308
- 309
- 310
- 311
- 312
- 313
- 314
- 315
- 316
- 317
- 318
- 319
- 320
- 321
- 322
- 323
- 324
- 325
- 326
- 327
- 328
- 329
- 330
- 331
- 332
- 333
- 334
- 335
- 336
- 337
- 338
- 339
- 340
- 341
- 342
- 343
- 344
- 345
- 346
- 347
- 348
- 349
- 350
- 351
- 352
- 353
- 354
- 355
- 356
- 357
- 358
- 359
- 360
- 361
- 362
- 363
- 364
- 365
- 366
- 367
- 368
- 369
- 370
- 371
- 372
- 373
- 374
- 375
- 376
- 377
- 378
- 379
- 380
- 381
- 382
- 383
- 384
- 385
- 386
- 387
- 388
- 389
- 390
- 391
- 392
- 393
- 394
- 395
- 396
- 397
- 398
- 399
- 400
- 401
- 402
- 403
- 404
- 405
- 406
- 407
- 408
- 409
- 410
- 411
- 412
- 413
- 414
- 415
- 416
- 417
- 418
- 419
- 420
- 421
- 422
- 423
- 424
- 425
- 426
- 427
- 428
- 429
- 430
- 431
- 432
- 433
- 434
- 435
- 436
- 437
- 438
- 439
- 440
- 441
- 442
- 443
- 444
- 445
- 446
- 447
- 448
- 449
- 450
- 451
- 452
- 453
- 454
- 455
- 456
- 457
- 458
- 459
- 460
- 461
- 462
- 463
- 464
- 465
- 466
- 467
- 468
- 469
- 470
- 471
- 472
- 473
- 474
- 475