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
  20 #include "../iio.h"
  21 #include "../sysfs.h"
  22 #include "dac.h"
  23
  24 #include "ad5446.h"
  25
  26 static void ad5446_store_sample(struct ad5446_state *st, unsigned val)
  27 {
  28         st->data.d16 = cpu_to_be16(AD5446_LOAD |
  29                                         (val << st->chip_info->left_shift));
  30 }
  31
  32 static void ad5542_store_sample(struct ad5446_state *st, unsigned val)
  33 {
  34         st->data.d16 = cpu_to_be16(val << st->chip_info->left_shift);
  35 }
  36
  37 static void ad5620_store_sample(struct ad5446_state *st, unsigned val)
  38 {
  39         st->data.d16 = cpu_to_be16(AD5620_LOAD |
  40                                         (val << st->chip_info->left_shift));
  41 }
  42
  43 static void ad5660_store_sample(struct ad5446_state *st, unsigned val)
  44 {
  45         val |= AD5660_LOAD;
  46         st->data.d24[0] = (val >> 16) & 0xFF;
  47         st->data.d24[1] = (val >> 8) & 0xFF;
  48         st->data.d24[2] = val & 0xFF;
  49 }
  50
  51 static void ad5620_store_pwr_down(struct ad5446_state *st, unsigned mode)
  52 {
  53         st->data.d16 = cpu_to_be16(mode << 14);
  54 }
  55
  56 static void ad5660_store_pwr_down(struct ad5446_state *st, unsigned mode)
  57 {
  58         unsigned val = mode << 16;
  59
  60         st->data.d24[0] = (val >> 16) & 0xFF;
  61         st->data.d24[1] = (val >> 8) & 0xFF;
  62         st->data.d24[2] = val & 0xFF;
  63 }
  64
  65 static ssize_t ad5446_write(struct device *dev,
  66                 struct device_attribute *attr,
  67                 const char *buf,
  68                 size_t len)
  69 {
  70         struct iio_dev *dev_info = dev_get_drvdata(dev);
  71         struct ad5446_state *st = dev_info->dev_data;
  72         int ret;
  73         long val;
  74
  75         ret = strict_strtol(buf, 10, &val);
  76         if (ret)
  77                 goto error_ret;
  78
  79         if (val > RES_MASK(st->chip_info->bits)) {
  80                 ret = -EINVAL;
  81                 goto error_ret;
  82         }
  83
  84         mutex_lock(&dev_info->mlock);
  85         st->cached_val = val;
  86         st->chip_info->store_sample(st, val);
  87         ret = spi_sync(st->spi, &st->msg);
  88         mutex_unlock(&dev_info->mlock);
  89
  90 error_ret:
  91         return ret ? ret : len;
  92 }
  93
  94 static IIO_DEV_ATTR_OUT_RAW(0, ad5446_write, 0);
  95
  96 static ssize_t ad5446_show_scale(struct device *dev,
  97                                 struct device_attribute *attr,
  98                                 char *buf)
  99 {
 100         struct iio_dev *dev_info = dev_get_drvdata(dev);
 101         struct ad5446_state *st = iio_dev_get_devdata(dev_info);
 102         /* Corresponds to Vref / 2^(bits) */
 103         unsigned int scale_uv = (st->vref_mv * 1000) >> st->chip_info->bits;
 104
 105         return sprintf(buf, "%d.%03d\n", scale_uv / 1000, scale_uv % 1000);
 106 }
 107 static IIO_DEVICE_ATTR(out_scale, S_IRUGO, ad5446_show_scale, NULL, 0);
 108
 109 static ssize_t ad5446_write_powerdown_mode(struct device *dev,
 110                                        struct device_attribute *attr,
 111                                        const char *buf, size_t len)
 112 {
 113         struct iio_dev *dev_info = dev_get_drvdata(dev);
 114         struct ad5446_state *st = dev_info->dev_data;
 115
 116         if (sysfs_streq(buf, "1kohm_to_gnd"))
 117                 st->pwr_down_mode = MODE_PWRDWN_1k;
 118         else if (sysfs_streq(buf, "100kohm_to_gnd"))
 119                 st->pwr_down_mode = MODE_PWRDWN_100k;
 120         else if (sysfs_streq(buf, "three_state"))
 121                 st->pwr_down_mode = MODE_PWRDWN_TRISTATE;
 122         else
 123                 return -EINVAL;
 124
 125         return len;
 126 }
 127
 128 static ssize_t ad5446_read_powerdown_mode(struct device *dev,
 129                                       struct device_attribute *attr, char *buf)
 130 {
 131         struct iio_dev *dev_info = dev_get_drvdata(dev);
 132         struct ad5446_state *st = dev_info->dev_data;
 133
 134         char mode[][15] = {"", "1kohm_to_gnd", "100kohm_to_gnd", "three_state"};
 135
 136         return sprintf(buf, "%s\n", mode[st->pwr_down_mode]);
 137 }
 138
 139 static ssize_t ad5446_read_dac_powerdown(struct device *dev,
 140                                            struct device_attribute *attr,
 141                                            char *buf)
 142 {
 143         struct iio_dev *dev_info = dev_get_drvdata(dev);
 144         struct ad5446_state *st = dev_info->dev_data;
 145
 146         return sprintf(buf, "%d\n", st->pwr_down);
 147 }
 148
 149 static ssize_t ad5446_write_dac_powerdown(struct device *dev,
 150                                             struct device_attribute *attr,
 151                                             const char *buf, size_t len)
 152 {
 153         struct iio_dev *dev_info = dev_get_drvdata(dev);
 154         struct ad5446_state *st = dev_info->dev_data;
 155         unsigned long readin;
 156         int ret;
 157
 158         ret = strict_strtol(buf, 10, &readin);
 159         if (ret)
 160                 return ret;
 161
 162         if (readin > 1)
 163                 ret = -EINVAL;
 164
 165         mutex_lock(&dev_info->mlock);
 166         st->pwr_down = readin;
 167
 168         if (st->pwr_down)
 169                 st->chip_info->store_pwr_down(st, st->pwr_down_mode);
 170         else
 171                 st->chip_info->store_sample(st, st->cached_val);
 172
 173         ret = spi_sync(st->spi, &st->msg);
 174         mutex_unlock(&dev_info->mlock);
 175
 176         return ret ? ret : len;
 177 }
 178
 179 static IIO_DEVICE_ATTR(out_powerdown_mode, S_IRUGO | S_IWUSR,
 180                         ad5446_read_powerdown_mode,
 181                         ad5446_write_powerdown_mode, 0);
 182
 183 static IIO_CONST_ATTR(out_powerdown_mode_available,
 184                         "1kohm_to_gnd 100kohm_to_gnd three_state");
 185
 186 static IIO_DEVICE_ATTR(out0_powerdown, S_IRUGO | S_IWUSR,
 187                         ad5446_read_dac_powerdown,
 188                         ad5446_write_dac_powerdown, 0);
 189
 190 static struct attribute *ad5446_attributes[] = {
 191         &iio_dev_attr_out0_raw.dev_attr.attr,
 192         &iio_dev_attr_out_scale.dev_attr.attr,
 193         &iio_dev_attr_out0_powerdown.dev_attr.attr,
 194         &iio_dev_attr_out_powerdown_mode.dev_attr.attr,
 195         &iio_const_attr_out_powerdown_mode_available.dev_attr.attr,
 196         NULL,
 197 };
 198
 199 static mode_t ad5446_attr_is_visible(struct kobject *kobj,
 200                                      struct attribute *attr, int n)
 201 {
 202         struct device *dev = container_of(kobj, struct device, kobj);
 203         struct iio_dev *dev_info = dev_get_drvdata(dev);
 204         struct ad5446_state *st = iio_dev_get_devdata(dev_info);
 205
 206         mode_t mode = attr->mode;
 207
 208         if (!st->chip_info->store_pwr_down &&
 209                 (attr == &iio_dev_attr_out0_powerdown.dev_attr.attr ||
 210                 attr == &iio_dev_attr_out_powerdown_mode.dev_attr.attr ||
 211                 attr ==
 212                 &iio_const_attr_out_powerdown_mode_available.dev_attr.attr))
 213                 mode = 0;
 214
 215         return mode;
 216 }
 217
 218 static const struct attribute_group ad5446_attribute_group = {
 219         .attrs = ad5446_attributes,
 220         .is_visible = ad5446_attr_is_visible,
 221 };
 222
 223 static const struct ad5446_chip_info ad5446_chip_info_tbl[] = {
 224         [ID_AD5444] = {
 225                 .bits = 12,
 226                 .storagebits = 16,
 227                 .left_shift = 2,
 228                 .store_sample = ad5446_store_sample,
 229         },
 230         [ID_AD5446] = {
 231                 .bits = 14,
 232                 .storagebits = 16,
 233                 .left_shift = 0,
 234                 .store_sample = ad5446_store_sample,
 235         },
 236         [ID_AD5541A] = {
 237                 .bits = 16,
 238                 .storagebits = 16,
 239                 .left_shift = 0,
 240                 .store_sample = ad5542_store_sample,
 241         },
 242         [ID_AD5542A] = {
 243                 .bits = 16,
 244                 .storagebits = 16,
 245                 .left_shift = 0,
 246                 .store_sample = ad5542_store_sample,
 247         },
 248         [ID_AD5543] = {
 249                 .bits = 16,
 250                 .storagebits = 16,
 251                 .left_shift = 0,
 252                 .store_sample = ad5542_store_sample,
 253         },
 254         [ID_AD5512A] = {
 255                 .bits = 12,
 256                 .storagebits = 16,
 257                 .left_shift = 4,
 258                 .store_sample = ad5542_store_sample,
 259         },
 260         [ID_AD5553] = {
 261                 .bits = 14,
 262                 .storagebits = 16,
 263                 .left_shift = 0,
 264                 .store_sample = ad5542_store_sample,
 265         },
 266         [ID_AD5601] = {
 267                 .bits = 8,
 268                 .storagebits = 16,
 269                 .left_shift = 6,
 270                 .store_sample = ad5542_store_sample,
 271                 .store_pwr_down = ad5620_store_pwr_down,
 272         },
 273         [ID_AD5611] = {
 274                 .bits = 10,
 275                 .storagebits = 16,
 276                 .left_shift = 4,
 277                 .store_sample = ad5542_store_sample,
 278                 .store_pwr_down = ad5620_store_pwr_down,
 279         },
 280         [ID_AD5621] = {
 281                 .bits = 12,
 282                 .storagebits = 16,
 283                 .left_shift = 2,
 284                 .store_sample = ad5542_store_sample,
 285                 .store_pwr_down = ad5620_store_pwr_down,
 286         },
 287         [ID_AD5620_2500] = {
 288                 .bits = 12,
 289                 .storagebits = 16,
 290                 .left_shift = 2,
 291                 .int_vref_mv = 2500,
 292                 .store_sample = ad5620_store_sample,
 293                 .store_pwr_down = ad5620_store_pwr_down,
 294         },
 295         [ID_AD5620_1250] = {
 296                 .bits = 12,
 297                 .storagebits = 16,
 298                 .left_shift = 2,
 299                 .int_vref_mv = 1250,
 300                 .store_sample = ad5620_store_sample,
 301                 .store_pwr_down = ad5620_store_pwr_down,
 302         },
 303         [ID_AD5640_2500] = {
 304                 .bits = 14,
 305                 .storagebits = 16,
 306                 .left_shift = 0,
 307                 .int_vref_mv = 2500,
 308                 .store_sample = ad5620_store_sample,
 309                 .store_pwr_down = ad5620_store_pwr_down,
 310         },
 311         [ID_AD5640_1250] = {
 312                 .bits = 14,
 313                 .storagebits = 16,
 314                 .left_shift = 0,
 315                 .int_vref_mv = 1250,
 316                 .store_sample = ad5620_store_sample,
 317                 .store_pwr_down = ad5620_store_pwr_down,
 318         },
 319         [ID_AD5660_2500] = {
 320                 .bits = 16,
 321                 .storagebits = 24,
 322                 .left_shift = 0,
 323                 .int_vref_mv = 2500,
 324                 .store_sample = ad5660_store_sample,
 325                 .store_pwr_down = ad5660_store_pwr_down,
 326         },
 327         [ID_AD5660_1250] = {
 328                 .bits = 16,
 329                 .storagebits = 24,
 330                 .left_shift = 0,
 331                 .int_vref_mv = 1250,
 332                 .store_sample = ad5660_store_sample,
 333                 .store_pwr_down = ad5660_store_pwr_down,
 334         },
 335 };
 336
 337 static int __devinit ad5446_probe(struct spi_device *spi)
 338 {
 339         struct ad5446_state *st;
 340         int ret, voltage_uv = 0;
 341
 342         st = kzalloc(sizeof(*st), GFP_KERNEL);
 343         if (st == NULL) {
 344                 ret = -ENOMEM;
 345                 goto error_ret;
 346         }
 347
 348         st->reg = regulator_get(&spi->dev, "vcc");
 349         if (!IS_ERR(st->reg)) {
 350                 ret = regulator_enable(st->reg);
 351                 if (ret)
 352                         goto error_put_reg;
 353
 354                 voltage_uv = regulator_get_voltage(st->reg);
 355         }
 356
 357         st->chip_info =
 358                 &ad5446_chip_info_tbl[spi_get_device_id(spi)->driver_data];
 359
 360         spi_set_drvdata(spi, st);
 361
 362         st->spi = spi;
 363
 364         st->indio_dev = iio_allocate_device(0);
 365         if (st->indio_dev == NULL) {
 366                 ret = -ENOMEM;
 367                 goto error_disable_reg;
 368         }
 369
 370         /* Estabilish that the iio_dev is a child of the spi device */
 371         st->indio_dev->dev.parent = &spi->dev;
 372         st->indio_dev->name = spi_get_device_id(spi)->name;
 373         st->indio_dev->attrs = &ad5446_attribute_group;
 374         st->indio_dev->dev_data = (void *)(st);
 375         st->indio_dev->driver_module = THIS_MODULE;
 376         st->indio_dev->modes = INDIO_DIRECT_MODE;
 377
 378         /* Setup default message */
 379
 380         st->xfer.tx_buf = &st->data;
 381         st->xfer.len = st->chip_info->storagebits / 8;
 382
 383         spi_message_init(&st->msg);
 384         spi_message_add_tail(&st->xfer, &st->msg);
 385
 386         switch (spi_get_device_id(spi)->driver_data) {
 387         case ID_AD5620_2500:
 388         case ID_AD5620_1250:
 389         case ID_AD5640_2500:
 390         case ID_AD5640_1250:
 391         case ID_AD5660_2500:
 392         case ID_AD5660_1250:
 393                 st->vref_mv = st->chip_info->int_vref_mv;
 394                 break;
 395         default:
 396                 if (voltage_uv)
 397                         st->vref_mv = voltage_uv / 1000;
 398                 else
 399                         dev_warn(&spi->dev,
 400                                  "reference voltage unspecified\n");
 401         }
 402
 403         ret = iio_device_register(st->indio_dev);
 404         if (ret)
 405                 goto error_free_device;
 406
 407         return 0;
 408
 409 error_free_device:
 410         iio_free_device(st->indio_dev);
 411 error_disable_reg:
 412         if (!IS_ERR(st->reg))
 413                 regulator_disable(st->reg);
 414 error_put_reg:
 415         if (!IS_ERR(st->reg))
 416                 regulator_put(st->reg);
 417         kfree(st);
 418 error_ret:
 419         return ret;
 420 }
 421
 422 static int ad5446_remove(struct spi_device *spi)
 423 {
 424         struct ad5446_state *st = spi_get_drvdata(spi);
 425         struct iio_dev *indio_dev = st->indio_dev;
 426
 427         iio_device_unregister(indio_dev);
 428         if (!IS_ERR(st->reg)) {
 429                 regulator_disable(st->reg);
 430                 regulator_put(st->reg);
 431         }
 432         kfree(st);
 433         return 0;
 434 }
 435
 436 static const struct spi_device_id ad5446_id[] = {
 437         {"ad5444", ID_AD5444},
 438         {"ad5446", ID_AD5446},
 439         {"ad5512a", ID_AD5512A},
 440         {"ad5541a", ID_AD5541A},
 441         {"ad5542a", ID_AD5542A},
 442         {"ad5543", ID_AD5543},
 443         {"ad5553", ID_AD5553},
 444         {"ad5601", ID_AD5601},
 445         {"ad5611", ID_AD5611},
 446         {"ad5621", ID_AD5621},
 447         {"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
 448         {"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
 449         {"ad5640-2500", ID_AD5640_2500},
 450         {"ad5640-1250", ID_AD5640_1250},
 451         {"ad5660-2500", ID_AD5660_2500},
 452         {"ad5660-1250", ID_AD5660_1250},
 453         {}
 454 };
 455
 456 static struct spi_driver ad5446_driver = {
 457         .driver = {
 458                 .name   = "ad5446",
 459                 .bus    = &spi_bus_type,
 460                 .owner  = THIS_MODULE,
 461         },
 462         .probe          = ad5446_probe,
 463         .remove         = __devexit_p(ad5446_remove),
 464         .id_table       = ad5446_id,
 465 };
 466
 467 static int __init ad5446_init(void)
 468 {
 469         return spi_register_driver(&ad5446_driver);
 470 }
 471 module_init(ad5446_init);
 472
 473 static void __exit ad5446_exit(void)
 474 {
 475         spi_unregister_driver(&ad5446_driver);
 476 }
 477 module_exit(ad5446_exit);
 478
 479 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 480 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
 481 MODULE_LICENSE("GPL v2");
 482 MODULE_ALIAS("spi:ad5446");