drivers/staging/iio/dac/ad5446.c

   1 /*
   2  * AD5446 SPI DAC driver
   3  *
   4  * Copyright 2010 Analog Devices Inc.
   5  *
   6  * Licensed under the GPL-2 or later.
   7  */
   8
   9 #include <linux/interrupt.h>
  10 #include <linux/workqueue.h>
  11 #include <linux/device.h>
  12 #include <linux/kernel.h>
  13 #include <linux/slab.h>
  14 #include <linux/sysfs.h>
  15 #include <linux/list.h>
  16 #include <linux/spi/spi.h>
  17 #include <linux/regulator/consumer.h>
  18 #include <linux/err.h>
  19 #include <linux/module.h>
  20
  21 #include "../iio.h"
  22 #include "../sysfs.h"
  23 #include "dac.h"
  24
  25 #include "ad5446.h"
  26
  27 static void ad5446_store_sample(struct ad5446_state *st, unsigned val)
  28 {
  29         st->data.d16 = cpu_to_be16(AD5446_LOAD | val);
  30 }
  31
  32 static void ad5542_store_sample(struct ad5446_state *st, unsigned val)
  33 {
  34         st->data.d16 = cpu_to_be16(val);
  35 }
  36
  37 static void ad5620_store_sample(struct ad5446_state *st, unsigned val)
  38 {
  39         st->data.d16 = cpu_to_be16(AD5620_LOAD | val);
  40 }
  41
  42 static void ad5660_store_sample(struct ad5446_state *st, unsigned val)
  43 {
  44         val |= AD5660_LOAD;
  45         st->data.d24[0] = (val >> 16) & 0xFF;
  46         st->data.d24[1] = (val >> 8) & 0xFF;
  47         st->data.d24[2] = val & 0xFF;
  48 }
  49
  50 static void ad5620_store_pwr_down(struct ad5446_state *st, unsigned mode)
  51 {
  52         st->data.d16 = cpu_to_be16(mode << 14);
  53 }
  54
  55 static void ad5660_store_pwr_down(struct ad5446_state *st, unsigned mode)
  56 {
  57         unsigned val = mode << 16;
  58
  59         st->data.d24[0] = (val >> 16) & 0xFF;
  60         st->data.d24[1] = (val >> 8) & 0xFF;
  61         st->data.d24[2] = val & 0xFF;
  62 }
  63
  64 static ssize_t ad5446_write_powerdown_mode(struct device *dev,
  65                                        struct device_attribute *attr,
  66                                        const char *buf, size_t len)
  67 {
  68         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  69         struct ad5446_state *st = iio_priv(indio_dev);
  70
  71         if (sysfs_streq(buf, "1kohm_to_gnd"))
  72                 st->pwr_down_mode = MODE_PWRDWN_1k;
  73         else if (sysfs_streq(buf, "100kohm_to_gnd"))
  74                 st->pwr_down_mode = MODE_PWRDWN_100k;
  75         else if (sysfs_streq(buf, "three_state"))
  76                 st->pwr_down_mode = MODE_PWRDWN_TRISTATE;
  77         else
  78                 return -EINVAL;
  79
  80         return len;
  81 }
  82
  83 static ssize_t ad5446_read_powerdown_mode(struct device *dev,
  84                                       struct device_attribute *attr, char *buf)
  85 {
  86         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  87         struct ad5446_state *st = iio_priv(indio_dev);
  88
  89         char mode[][15] = {"", "1kohm_to_gnd", "100kohm_to_gnd", "three_state"};
  90
  91         return sprintf(buf, "%s\n", mode[st->pwr_down_mode]);
  92 }
  93
  94 static ssize_t ad5446_read_dac_powerdown(struct device *dev,
  95                                            struct device_attribute *attr,
  96                                            char *buf)
  97 {
  98         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  99         struct ad5446_state *st = iio_priv(indio_dev);
 100
 101         return sprintf(buf, "%d\n", st->pwr_down);
 102 }
 103
 104 static ssize_t ad5446_write_dac_powerdown(struct device *dev,
 105                                             struct device_attribute *attr,
 106                                             const char *buf, size_t len)
 107 {
 108         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 109         struct ad5446_state *st = iio_priv(indio_dev);
 110         unsigned long readin;
 111         int ret;
 112
 113         ret = strict_strtol(buf, 10, &readin);
 114         if (ret)
 115                 return ret;
 116
 117         if (readin > 1)
 118                 ret = -EINVAL;
 119
 120         mutex_lock(&indio_dev->mlock);
 121         st->pwr_down = readin;
 122
 123         if (st->pwr_down)
 124                 st->chip_info->store_pwr_down(st, st->pwr_down_mode);
 125         else
 126                 st->chip_info->store_sample(st, st->cached_val);
 127
 128         ret = spi_sync(st->spi, &st->msg);
 129         mutex_unlock(&indio_dev->mlock);
 130
 131         return ret ? ret : len;
 132 }
 133
 134 static IIO_DEVICE_ATTR(out_voltage_powerdown_mode, S_IRUGO | S_IWUSR,
 135                         ad5446_read_powerdown_mode,
 136                         ad5446_write_powerdown_mode, 0);
 137
 138 static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
 139                         "1kohm_to_gnd 100kohm_to_gnd three_state");
 140
 141 static IIO_DEVICE_ATTR(out_voltage0_powerdown, S_IRUGO | S_IWUSR,
 142                         ad5446_read_dac_powerdown,
 143                         ad5446_write_dac_powerdown, 0);
 144
 145 static struct attribute *ad5446_attributes[] = {
 146         &iio_dev_attr_out_voltage0_powerdown.dev_attr.attr,
 147         &iio_dev_attr_out_voltage_powerdown_mode.dev_attr.attr,
 148         &iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr,
 149         NULL,
 150 };
 151
 152 static umode_t ad5446_attr_is_visible(struct kobject *kobj,
 153                                      struct attribute *attr, int n)
 154 {
 155         struct device *dev = container_of(kobj, struct device, kobj);
 156         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 157         struct ad5446_state *st = iio_priv(indio_dev);
 158
 159         umode_t mode = attr->mode;
 160
 161         if (!st->chip_info->store_pwr_down &&
 162                 (attr == &iio_dev_attr_out_voltage0_powerdown.dev_attr.attr ||
 163                 attr == &iio_dev_attr_out_voltage_powerdown_mode.
 164                  dev_attr.attr ||
 165                 attr ==
 166                 &iio_const_attr_out_voltage_powerdown_mode_available.
 167                  dev_attr.attr))
 168                 mode = 0;
 169
 170         return mode;
 171 }
 172
 173 static const struct attribute_group ad5446_attribute_group = {
 174         .attrs = ad5446_attributes,
 175         .is_visible = ad5446_attr_is_visible,
 176 };
 177
 178 #define AD5446_CHANNEL(bits, storage, shift) { \
 179         .type = IIO_VOLTAGE, \
 180         .indexed = 1, \
 181         .output = 1, \
 182         .channel = 0, \
 183         .info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT, \
 184         .scan_type = IIO_ST('u', (bits), (storage), (shift)) \
 185 }
 186
 187 static const struct ad5446_chip_info ad5446_chip_info_tbl[] = {
 188         [ID_AD5444] = {
 189                 .channel = AD5446_CHANNEL(12, 16, 2),
 190                 .store_sample = ad5446_store_sample,
 191         },
 192         [ID_AD5446] = {
 193                 .channel = AD5446_CHANNEL(14, 16, 0),
 194                 .store_sample = ad5446_store_sample,
 195         },
 196         [ID_AD5541A] = {
 197                 .channel = AD5446_CHANNEL(16, 16, 0),
 198                 .store_sample = ad5542_store_sample,
 199         },
 200         [ID_AD5542A] = {
 201                 .channel = AD5446_CHANNEL(16, 16, 0),
 202                 .store_sample = ad5542_store_sample,
 203         },
 204         [ID_AD5543] = {
 205                 .channel = AD5446_CHANNEL(16, 16, 0),
 206                 .store_sample = ad5542_store_sample,
 207         },
 208         [ID_AD5512A] = {
 209                 .channel = AD5446_CHANNEL(12, 16, 4),
 210                 .store_sample = ad5542_store_sample,
 211         },
 212         [ID_AD5553] = {
 213                 .channel = AD5446_CHANNEL(14, 16, 0),
 214                 .store_sample = ad5542_store_sample,
 215         },
 216         [ID_AD5601] = {
 217                 .channel = AD5446_CHANNEL(8, 16, 6),
 218                 .store_sample = ad5542_store_sample,
 219                 .store_pwr_down = ad5620_store_pwr_down,
 220         },
 221         [ID_AD5611] = {
 222                 .channel = AD5446_CHANNEL(10, 16, 4),
 223                 .store_sample = ad5542_store_sample,
 224                 .store_pwr_down = ad5620_store_pwr_down,
 225         },
 226         [ID_AD5621] = {
 227                 .channel = AD5446_CHANNEL(12, 16, 2),
 228                 .store_sample = ad5542_store_sample,
 229                 .store_pwr_down = ad5620_store_pwr_down,
 230         },
 231         [ID_AD5620_2500] = {
 232                 .channel = AD5446_CHANNEL(12, 16, 2),
 233                 .int_vref_mv = 2500,
 234                 .store_sample = ad5620_store_sample,
 235                 .store_pwr_down = ad5620_store_pwr_down,
 236         },
 237         [ID_AD5620_1250] = {
 238                 .channel = AD5446_CHANNEL(12, 16, 2),
 239                 .int_vref_mv = 1250,
 240                 .store_sample = ad5620_store_sample,
 241                 .store_pwr_down = ad5620_store_pwr_down,
 242         },
 243         [ID_AD5640_2500] = {
 244                 .channel = AD5446_CHANNEL(14, 16, 0),
 245                 .int_vref_mv = 2500,
 246                 .store_sample = ad5620_store_sample,
 247                 .store_pwr_down = ad5620_store_pwr_down,
 248         },
 249         [ID_AD5640_1250] = {
 250                 .channel = AD5446_CHANNEL(14, 16, 0),
 251                 .int_vref_mv = 1250,
 252                 .store_sample = ad5620_store_sample,
 253                 .store_pwr_down = ad5620_store_pwr_down,
 254         },
 255         [ID_AD5660_2500] = {
 256                 .channel = AD5446_CHANNEL(16, 16, 0),
 257                 .int_vref_mv = 2500,
 258                 .store_sample = ad5660_store_sample,
 259                 .store_pwr_down = ad5660_store_pwr_down,
 260         },
 261         [ID_AD5660_1250] = {
 262                 .channel = AD5446_CHANNEL(16, 16, 0),
 263                 .int_vref_mv = 1250,
 264                 .store_sample = ad5660_store_sample,
 265                 .store_pwr_down = ad5660_store_pwr_down,
 266         },
 267 };
 268
 269 static int ad5446_read_raw(struct iio_dev *indio_dev,
 270                            struct iio_chan_spec const *chan,
 271                            int *val,
 272                            int *val2,
 273                            long m)
 274 {
 275         struct ad5446_state *st = iio_priv(indio_dev);
 276         unsigned long scale_uv;
 277
 278         switch (m) {
 279         case IIO_CHAN_INFO_SCALE:
 280                 scale_uv = (st->vref_mv * 1000) >> chan->scan_type.realbits;
 281                 *val =  scale_uv / 1000;
 282                 *val2 = (scale_uv % 1000) * 1000;
 283                 return IIO_VAL_INT_PLUS_MICRO;
 284
 285         }
 286         return -EINVAL;
 287 }
 288
 289 static int ad5446_write_raw(struct iio_dev *indio_dev,
 290                                struct iio_chan_spec const *chan,
 291                                int val,
 292                                int val2,
 293                                long mask)
 294 {
 295         struct ad5446_state *st = iio_priv(indio_dev);
 296         int ret;
 297
 298         switch (mask) {
 299         case 0:
 300                 if (val >= (1 << chan->scan_type.realbits) || val < 0)
 301                         return -EINVAL;
 302
 303                 val <<= chan->scan_type.shift;
 304                 mutex_lock(&indio_dev->mlock);
 305                 st->cached_val = val;
 306                 st->chip_info->store_sample(st, val);
 307                 ret = spi_sync(st->spi, &st->msg);
 308                 mutex_unlock(&indio_dev->mlock);
 309                 break;
 310         default:
 311                 ret = -EINVAL;
 312         }
 313
 314         return ret;
 315 }
 316
 317 static const struct iio_info ad5446_info = {
 318         .read_raw = ad5446_read_raw,
 319         .write_raw = ad5446_write_raw,
 320         .attrs = &ad5446_attribute_group,
 321         .driver_module = THIS_MODULE,
 322 };
 323
 324 static int __devinit ad5446_probe(struct spi_device *spi)
 325 {
 326         struct ad5446_state *st;
 327         struct iio_dev *indio_dev;
 328         struct regulator *reg;
 329         int ret, voltage_uv = 0;
 330
 331         reg = regulator_get(&spi->dev, "vcc");
 332         if (!IS_ERR(reg)) {
 333                 ret = regulator_enable(reg);
 334                 if (ret)
 335                         goto error_put_reg;
 336
 337                 voltage_uv = regulator_get_voltage(reg);
 338         }
 339
 340         indio_dev = iio_allocate_device(sizeof(*st));
 341         if (indio_dev == NULL) {
 342                 ret = -ENOMEM;
 343                 goto error_disable_reg;
 344         }
 345         st = iio_priv(indio_dev);
 346         st->chip_info =
 347                 &ad5446_chip_info_tbl[spi_get_device_id(spi)->driver_data];
 348
 349         spi_set_drvdata(spi, indio_dev);
 350         st->reg = reg;
 351         st->spi = spi;
 352
 353         /* Estabilish that the iio_dev is a child of the spi device */
 354         indio_dev->dev.parent = &spi->dev;
 355         indio_dev->name = spi_get_device_id(spi)->name;
 356         indio_dev->info = &ad5446_info;
 357         indio_dev->modes = INDIO_DIRECT_MODE;
 358         indio_dev->channels = &st->chip_info->channel;
 359         indio_dev->num_channels = 1;
 360
 361         /* Setup default message */
 362
 363         st->xfer.tx_buf = &st->data;
 364         st->xfer.len = st->chip_info->channel.scan_type.storagebits / 8;
 365
 366         spi_message_init(&st->msg);
 367         spi_message_add_tail(&st->xfer, &st->msg);
 368
 369         switch (spi_get_device_id(spi)->driver_data) {
 370         case ID_AD5620_2500:
 371         case ID_AD5620_1250:
 372         case ID_AD5640_2500:
 373         case ID_AD5640_1250:
 374         case ID_AD5660_2500:
 375         case ID_AD5660_1250:
 376                 st->vref_mv = st->chip_info->int_vref_mv;
 377                 break;
 378         default:
 379                 if (voltage_uv)
 380                         st->vref_mv = voltage_uv / 1000;
 381                 else
 382                         dev_warn(&spi->dev,
 383                                  "reference voltage unspecified\n");
 384         }
 385
 386         ret = iio_device_register(indio_dev);
 387         if (ret)
 388                 goto error_free_device;
 389
 390         return 0;
 391
 392 error_free_device:
 393         iio_free_device(indio_dev);
 394 error_disable_reg:
 395         if (!IS_ERR(reg))
 396                 regulator_disable(reg);
 397 error_put_reg:
 398         if (!IS_ERR(reg))
 399                 regulator_put(reg);
 400
 401         return ret;
 402 }
 403
 404 static int ad5446_remove(struct spi_device *spi)
 405 {
 406         struct iio_dev *indio_dev = spi_get_drvdata(spi);
 407         struct ad5446_state *st = iio_priv(indio_dev);
 408
 409         iio_device_unregister(indio_dev);
 410         if (!IS_ERR(st->reg)) {
 411                 regulator_disable(st->reg);
 412                 regulator_put(st->reg);
 413         }
 414         iio_free_device(indio_dev);
 415
 416         return 0;
 417 }
 418
 419 static const struct spi_device_id ad5446_id[] = {
 420         {"ad5444", ID_AD5444},
 421         {"ad5446", ID_AD5446},
 422         {"ad5512a", ID_AD5512A},
 423         {"ad5541a", ID_AD5541A},
 424         {"ad5542a", ID_AD5542A},
 425         {"ad5543", ID_AD5543},
 426         {"ad5553", ID_AD5553},
 427         {"ad5601", ID_AD5601},
 428         {"ad5611", ID_AD5611},
 429         {"ad5621", ID_AD5621},
 430         {"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
 431         {"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
 432         {"ad5640-2500", ID_AD5640_2500},
 433         {"ad5640-1250", ID_AD5640_1250},
 434         {"ad5660-2500", ID_AD5660_2500},
 435         {"ad5660-1250", ID_AD5660_1250},
 436         {}
 437 };
 438 MODULE_DEVICE_TABLE(spi, ad5446_id);
 439
 440 static struct spi_driver ad5446_driver = {
 441         .driver = {
 442                 .name   = "ad5446",
 443                 .owner  = THIS_MODULE,
 444         },
 445         .probe          = ad5446_probe,
 446         .remove         = __devexit_p(ad5446_remove),
 447         .id_table       = ad5446_id,
 448 };
 449 module_spi_driver(ad5446_driver);
 450
 451 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 452 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
 453 MODULE_LICENSE("GPL v2");