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 |
  30                                         (val << st->chip_info->left_shift));
  31 }
  32
  33 static void ad5542_store_sample(struct ad5446_state *st, unsigned val)
  34 {
  35         st->data.d16 = cpu_to_be16(val << st->chip_info->left_shift);
  36 }
  37
  38 static void ad5620_store_sample(struct ad5446_state *st, unsigned val)
  39 {
  40         st->data.d16 = cpu_to_be16(AD5620_LOAD |
  41                                         (val << st->chip_info->left_shift));
  42 }
  43
  44 static void ad5660_store_sample(struct ad5446_state *st, unsigned val)
  45 {
  46         val |= AD5660_LOAD;
  47         st->data.d24[0] = (val >> 16) & 0xFF;
  48         st->data.d24[1] = (val >> 8) & 0xFF;
  49         st->data.d24[2] = val & 0xFF;
  50 }
  51
  52 static void ad5620_store_pwr_down(struct ad5446_state *st, unsigned mode)
  53 {
  54         st->data.d16 = cpu_to_be16(mode << 14);
  55 }
  56
  57 static void ad5660_store_pwr_down(struct ad5446_state *st, unsigned mode)
  58 {
  59         unsigned val = mode << 16;
  60
  61         st->data.d24[0] = (val >> 16) & 0xFF;
  62         st->data.d24[1] = (val >> 8) & 0xFF;
  63         st->data.d24[2] = val & 0xFF;
  64 }
  65
  66 static ssize_t ad5446_write(struct device *dev,
  67                 struct device_attribute *attr,
  68                 const char *buf,
  69                 size_t len)
  70 {
  71         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  72         struct ad5446_state *st = iio_priv(indio_dev);
  73         int ret;
  74         long val;
  75
  76         ret = strict_strtol(buf, 10, &val);
  77         if (ret)
  78                 goto error_ret;
  79
  80         if (val > RES_MASK(st->chip_info->bits)) {
  81                 ret = -EINVAL;
  82                 goto error_ret;
  83         }
  84
  85         mutex_lock(&indio_dev->mlock);
  86         st->cached_val = val;
  87         st->chip_info->store_sample(st, val);
  88         ret = spi_sync(st->spi, &st->msg);
  89         mutex_unlock(&indio_dev->mlock);
  90
  91 error_ret:
  92         return ret ? ret : len;
  93 }
  94
  95 static IIO_DEV_ATTR_OUT_RAW(0, ad5446_write, 0);
  96
  97 static ssize_t ad5446_show_scale(struct device *dev,
  98                                 struct device_attribute *attr,
  99                                 char *buf)
 100 {
 101         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 102         struct ad5446_state *st = iio_priv(indio_dev);
 103         /* Corresponds to Vref / 2^(bits) */
 104         unsigned int scale_uv = (st->vref_mv * 1000) >> st->chip_info->bits;
 105
 106         return sprintf(buf, "%d.%03d\n", scale_uv / 1000, scale_uv % 1000);
 107 }
 108 static IIO_DEVICE_ATTR(out_voltage_scale, S_IRUGO, ad5446_show_scale, NULL, 0);
 109
 110 static ssize_t ad5446_write_powerdown_mode(struct device *dev,
 111                                        struct device_attribute *attr,
 112                                        const char *buf, size_t len)
 113 {
 114         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 115         struct ad5446_state *st = iio_priv(indio_dev);
 116
 117         if (sysfs_streq(buf, "1kohm_to_gnd"))
 118                 st->pwr_down_mode = MODE_PWRDWN_1k;
 119         else if (sysfs_streq(buf, "100kohm_to_gnd"))
 120                 st->pwr_down_mode = MODE_PWRDWN_100k;
 121         else if (sysfs_streq(buf, "three_state"))
 122                 st->pwr_down_mode = MODE_PWRDWN_TRISTATE;
 123         else
 124                 return -EINVAL;
 125
 126         return len;
 127 }
 128
 129 static ssize_t ad5446_read_powerdown_mode(struct device *dev,
 130                                       struct device_attribute *attr, char *buf)
 131 {
 132         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 133         struct ad5446_state *st = iio_priv(indio_dev);
 134
 135         char mode[][15] = {"", "1kohm_to_gnd", "100kohm_to_gnd", "three_state"};
 136
 137         return sprintf(buf, "%s\n", mode[st->pwr_down_mode]);
 138 }
 139
 140 static ssize_t ad5446_read_dac_powerdown(struct device *dev,
 141                                            struct device_attribute *attr,
 142                                            char *buf)
 143 {
 144         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 145         struct ad5446_state *st = iio_priv(indio_dev);
 146
 147         return sprintf(buf, "%d\n", st->pwr_down);
 148 }
 149
 150 static ssize_t ad5446_write_dac_powerdown(struct device *dev,
 151                                             struct device_attribute *attr,
 152                                             const char *buf, size_t len)
 153 {
 154         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 155         struct ad5446_state *st = iio_priv(indio_dev);
 156         unsigned long readin;
 157         int ret;
 158
 159         ret = strict_strtol(buf, 10, &readin);
 160         if (ret)
 161                 return ret;
 162
 163         if (readin > 1)
 164                 ret = -EINVAL;
 165
 166         mutex_lock(&indio_dev->mlock);
 167         st->pwr_down = readin;
 168
 169         if (st->pwr_down)
 170                 st->chip_info->store_pwr_down(st, st->pwr_down_mode);
 171         else
 172                 st->chip_info->store_sample(st, st->cached_val);
 173
 174         ret = spi_sync(st->spi, &st->msg);
 175         mutex_unlock(&indio_dev->mlock);
 176
 177         return ret ? ret : len;
 178 }
 179
 180 static IIO_DEVICE_ATTR(out_voltage_powerdown_mode, S_IRUGO | S_IWUSR,
 181                         ad5446_read_powerdown_mode,
 182                         ad5446_write_powerdown_mode, 0);
 183
 184 static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
 185                         "1kohm_to_gnd 100kohm_to_gnd three_state");
 186
 187 static IIO_DEVICE_ATTR(out_voltage0_powerdown, S_IRUGO | S_IWUSR,
 188                         ad5446_read_dac_powerdown,
 189                         ad5446_write_dac_powerdown, 0);
 190
 191 static struct attribute *ad5446_attributes[] = {
 192         &iio_dev_attr_out_voltage0_raw.dev_attr.attr,
 193         &iio_dev_attr_out_voltage_scale.dev_attr.attr,
 194         &iio_dev_attr_out_voltage0_powerdown.dev_attr.attr,
 195         &iio_dev_attr_out_voltage_powerdown_mode.dev_attr.attr,
 196         &iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr,
 197         NULL,
 198 };
 199
 200 static mode_t ad5446_attr_is_visible(struct kobject *kobj,
 201                                      struct attribute *attr, int n)
 202 {
 203         struct device *dev = container_of(kobj, struct device, kobj);
 204         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 205         struct ad5446_state *st = iio_priv(indio_dev);
 206
 207         mode_t mode = attr->mode;
 208
 209         if (!st->chip_info->store_pwr_down &&
 210                 (attr == &iio_dev_attr_out_voltage0_powerdown.dev_attr.attr ||
 211                 attr == &iio_dev_attr_out_voltage_powerdown_mode.
 212                  dev_attr.attr ||
 213                 attr ==
 214                 &iio_const_attr_out_voltage_powerdown_mode_available.
 215                  dev_attr.attr))
 216                 mode = 0;
 217
 218         return mode;
 219 }
 220
 221 static const struct attribute_group ad5446_attribute_group = {
 222         .attrs = ad5446_attributes,
 223         .is_visible = ad5446_attr_is_visible,
 224 };
 225
 226 static const struct ad5446_chip_info ad5446_chip_info_tbl[] = {
 227         [ID_AD5444] = {
 228                 .bits = 12,
 229                 .storagebits = 16,
 230                 .left_shift = 2,
 231                 .store_sample = ad5446_store_sample,
 232         },
 233         [ID_AD5446] = {
 234                 .bits = 14,
 235                 .storagebits = 16,
 236                 .left_shift = 0,
 237                 .store_sample = ad5446_store_sample,
 238         },
 239         [ID_AD5541A] = {
 240                 .bits = 16,
 241                 .storagebits = 16,
 242                 .left_shift = 0,
 243                 .store_sample = ad5542_store_sample,
 244         },
 245         [ID_AD5542A] = {
 246                 .bits = 16,
 247                 .storagebits = 16,
 248                 .left_shift = 0,
 249                 .store_sample = ad5542_store_sample,
 250         },
 251         [ID_AD5543] = {
 252                 .bits = 16,
 253                 .storagebits = 16,
 254                 .left_shift = 0,
 255                 .store_sample = ad5542_store_sample,
 256         },
 257         [ID_AD5512A] = {
 258                 .bits = 12,
 259                 .storagebits = 16,
 260                 .left_shift = 4,
 261                 .store_sample = ad5542_store_sample,
 262         },
 263         [ID_AD5553] = {
 264                 .bits = 14,
 265                 .storagebits = 16,
 266                 .left_shift = 0,
 267                 .store_sample = ad5542_store_sample,
 268         },
 269         [ID_AD5601] = {
 270                 .bits = 8,
 271                 .storagebits = 16,
 272                 .left_shift = 6,
 273                 .store_sample = ad5542_store_sample,
 274                 .store_pwr_down = ad5620_store_pwr_down,
 275         },
 276         [ID_AD5611] = {
 277                 .bits = 10,
 278                 .storagebits = 16,
 279                 .left_shift = 4,
 280                 .store_sample = ad5542_store_sample,
 281                 .store_pwr_down = ad5620_store_pwr_down,
 282         },
 283         [ID_AD5621] = {
 284                 .bits = 12,
 285                 .storagebits = 16,
 286                 .left_shift = 2,
 287                 .store_sample = ad5542_store_sample,
 288                 .store_pwr_down = ad5620_store_pwr_down,
 289         },
 290         [ID_AD5620_2500] = {
 291                 .bits = 12,
 292                 .storagebits = 16,
 293                 .left_shift = 2,
 294                 .int_vref_mv = 2500,
 295                 .store_sample = ad5620_store_sample,
 296                 .store_pwr_down = ad5620_store_pwr_down,
 297         },
 298         [ID_AD5620_1250] = {
 299                 .bits = 12,
 300                 .storagebits = 16,
 301                 .left_shift = 2,
 302                 .int_vref_mv = 1250,
 303                 .store_sample = ad5620_store_sample,
 304                 .store_pwr_down = ad5620_store_pwr_down,
 305         },
 306         [ID_AD5640_2500] = {
 307                 .bits = 14,
 308                 .storagebits = 16,
 309                 .left_shift = 0,
 310                 .int_vref_mv = 2500,
 311                 .store_sample = ad5620_store_sample,
 312                 .store_pwr_down = ad5620_store_pwr_down,
 313         },
 314         [ID_AD5640_1250] = {
 315                 .bits = 14,
 316                 .storagebits = 16,
 317                 .left_shift = 0,
 318                 .int_vref_mv = 1250,
 319                 .store_sample = ad5620_store_sample,
 320                 .store_pwr_down = ad5620_store_pwr_down,
 321         },
 322         [ID_AD5660_2500] = {
 323                 .bits = 16,
 324                 .storagebits = 24,
 325                 .left_shift = 0,
 326                 .int_vref_mv = 2500,
 327                 .store_sample = ad5660_store_sample,
 328                 .store_pwr_down = ad5660_store_pwr_down,
 329         },
 330         [ID_AD5660_1250] = {
 331                 .bits = 16,
 332                 .storagebits = 24,
 333                 .left_shift = 0,
 334                 .int_vref_mv = 1250,
 335                 .store_sample = ad5660_store_sample,
 336                 .store_pwr_down = ad5660_store_pwr_down,
 337         },
 338 };
 339
 340 static const struct iio_info ad5446_info = {
 341         .attrs = &ad5446_attribute_group,
 342         .driver_module = THIS_MODULE,
 343 };
 344
 345 static int __devinit ad5446_probe(struct spi_device *spi)
 346 {
 347         struct ad5446_state *st;
 348         struct iio_dev *indio_dev;
 349         struct regulator *reg;
 350         int ret, voltage_uv = 0;
 351
 352         reg = regulator_get(&spi->dev, "vcc");
 353         if (!IS_ERR(reg)) {
 354                 ret = regulator_enable(reg);
 355                 if (ret)
 356                         goto error_put_reg;
 357
 358                 voltage_uv = regulator_get_voltage(reg);
 359         }
 360
 361         indio_dev = iio_allocate_device(sizeof(*st));
 362         if (indio_dev == NULL) {
 363                 ret = -ENOMEM;
 364                 goto error_disable_reg;
 365         }
 366         st = iio_priv(indio_dev);
 367         st->chip_info =
 368                 &ad5446_chip_info_tbl[spi_get_device_id(spi)->driver_data];
 369
 370         spi_set_drvdata(spi, indio_dev);
 371         st->reg = reg;
 372         st->spi = spi;
 373
 374         /* Estabilish that the iio_dev is a child of the spi device */
 375         indio_dev->dev.parent = &spi->dev;
 376         indio_dev->name = spi_get_device_id(spi)->name;
 377         indio_dev->info = &ad5446_info;
 378         indio_dev->modes = INDIO_DIRECT_MODE;
 379
 380         /* Setup default message */
 381
 382         st->xfer.tx_buf = &st->data;
 383         st->xfer.len = st->chip_info->storagebits / 8;
 384
 385         spi_message_init(&st->msg);
 386         spi_message_add_tail(&st->xfer, &st->msg);
 387
 388         switch (spi_get_device_id(spi)->driver_data) {
 389         case ID_AD5620_2500:
 390         case ID_AD5620_1250:
 391         case ID_AD5640_2500:
 392         case ID_AD5640_1250:
 393         case ID_AD5660_2500:
 394         case ID_AD5660_1250:
 395                 st->vref_mv = st->chip_info->int_vref_mv;
 396                 break;
 397         default:
 398                 if (voltage_uv)
 399                         st->vref_mv = voltage_uv / 1000;
 400                 else
 401                         dev_warn(&spi->dev,
 402                                  "reference voltage unspecified\n");
 403         }
 404
 405         ret = iio_device_register(indio_dev);
 406         if (ret)
 407                 goto error_free_device;
 408
 409         return 0;
 410
 411 error_free_device:
 412         iio_free_device(indio_dev);
 413 error_disable_reg:
 414         if (!IS_ERR(reg))
 415                 regulator_disable(reg);
 416 error_put_reg:
 417         if (!IS_ERR(reg))
 418                 regulator_put(reg);
 419
 420         return ret;
 421 }
 422
 423 static int ad5446_remove(struct spi_device *spi)
 424 {
 425         struct iio_dev *indio_dev = spi_get_drvdata(spi);
 426         struct ad5446_state *st = iio_priv(indio_dev);
 427
 428         iio_device_unregister(indio_dev);
 429         if (!IS_ERR(st->reg)) {
 430                 regulator_disable(st->reg);
 431                 regulator_put(st->reg);
 432         }
 433         iio_free_device(indio_dev);
 434
 435         return 0;
 436 }
 437
 438 static const struct spi_device_id ad5446_id[] = {
 439         {"ad5444", ID_AD5444},
 440         {"ad5446", ID_AD5446},
 441         {"ad5512a", ID_AD5512A},
 442         {"ad5541a", ID_AD5541A},
 443         {"ad5542a", ID_AD5542A},
 444         {"ad5543", ID_AD5543},
 445         {"ad5553", ID_AD5553},
 446         {"ad5601", ID_AD5601},
 447         {"ad5611", ID_AD5611},
 448         {"ad5621", ID_AD5621},
 449         {"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
 450         {"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
 451         {"ad5640-2500", ID_AD5640_2500},
 452         {"ad5640-1250", ID_AD5640_1250},
 453         {"ad5660-2500", ID_AD5660_2500},
 454         {"ad5660-1250", ID_AD5660_1250},
 455         {}
 456 };
 457
 458 static struct spi_driver ad5446_driver = {
 459         .driver = {
 460                 .name   = "ad5446",
 461                 .bus    = &spi_bus_type,
 462                 .owner  = THIS_MODULE,
 463         },
 464         .probe          = ad5446_probe,
 465         .remove         = __devexit_p(ad5446_remove),
 466         .id_table       = ad5446_id,
 467 };
 468
 469 static int __init ad5446_init(void)
 470 {
 471         return spi_register_driver(&ad5446_driver);
 472 }
 473 module_init(ad5446_init);
 474
 475 static void __exit ad5446_exit(void)
 476 {
 477         spi_unregister_driver(&ad5446_driver);
 478 }
 479 module_exit(ad5446_exit);
 480
 481 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 482 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
 483 MODULE_LICENSE("GPL v2");
 484 MODULE_ALIAS("spi:ad5446");