linux/drivers/misc/ad525x_dpot.c
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   1/*
   2 * ad525x_dpot: Driver for the Analog Devices digital potentiometers
   3 * Copyright (c) 2009-2010 Analog Devices, Inc.
   4 * Author: Michael Hennerich <hennerich@blackfin.uclinux.org>
   5 *
   6 * DEVID                #Wipers         #Positions      Resistor Options (kOhm)
   7 * AD5258               1               64              1, 10, 50, 100
   8 * AD5259               1               256             5, 10, 50, 100
   9 * AD5251               2               64              1, 10, 50, 100
  10 * AD5252               2               256             1, 10, 50, 100
  11 * AD5255               3               512             25, 250
  12 * AD5253               4               64              1, 10, 50, 100
  13 * AD5254               4               256             1, 10, 50, 100
  14 * AD5160               1               256             5, 10, 50, 100
  15 * AD5161               1               256             5, 10, 50, 100
  16 * AD5162               2               256             2.5, 10, 50, 100
  17 * AD5165               1               256             100
  18 * AD5200               1               256             10, 50
  19 * AD5201               1               33              10, 50
  20 * AD5203               4               64              10, 100
  21 * AD5204               4               256             10, 50, 100
  22 * AD5206               6               256             10, 50, 100
  23 * AD5207               2               256             10, 50, 100
  24 * AD5231               1               1024            10, 50, 100
  25 * AD5232               2               256             10, 50, 100
  26 * AD5233               4               64              10, 50, 100
  27 * AD5235               2               1024            25, 250
  28 * AD5260               1               256             20, 50, 200
  29 * AD5262               2               256             20, 50, 200
  30 * AD5263               4               256             20, 50, 200
  31 * AD5290               1               256             10, 50, 100
  32 * AD5291               1               256             20, 50, 100  (20-TP)
  33 * AD5292               1               1024            20, 50, 100  (20-TP)
  34 * AD5293               1               1024            20, 50, 100
  35 * AD7376               1               128             10, 50, 100, 1M
  36 * AD8400               1               256             1, 10, 50, 100
  37 * AD8402               2               256             1, 10, 50, 100
  38 * AD8403               4               256             1, 10, 50, 100
  39 * ADN2850              3               512             25, 250
  40 * AD5241               1               256             10, 100, 1M
  41 * AD5246               1               128             5, 10, 50, 100
  42 * AD5247               1               128             5, 10, 50, 100
  43 * AD5245               1               256             5, 10, 50, 100
  44 * AD5243               2               256             2.5, 10, 50, 100
  45 * AD5248               2               256             2.5, 10, 50, 100
  46 * AD5242               2               256             20, 50, 200
  47 * AD5280               1               256             20, 50, 200
  48 * AD5282               2               256             20, 50, 200
  49 * ADN2860              3               512             25, 250
  50 * AD5273               1               64              1, 10, 50, 100 (OTP)
  51 * AD5171               1               64              5, 10, 50, 100 (OTP)
  52 * AD5170               1               256             2.5, 10, 50, 100 (OTP)
  53 * AD5172               2               256             2.5, 10, 50, 100 (OTP)
  54 * AD5173               2               256             2.5, 10, 50, 100 (OTP)
  55 * AD5270               1               1024            20, 50, 100 (50-TP)
  56 * AD5271               1               256             20, 50, 100 (50-TP)
  57 * AD5272               1               1024            20, 50, 100 (50-TP)
  58 * AD5274               1               256             20, 50, 100 (50-TP)
  59 *
  60 * See Documentation/misc-devices/ad525x_dpot.txt for more info.
  61 *
  62 * derived from ad5258.c
  63 * Copyright (c) 2009 Cyber Switching, Inc.
  64 * Author: Chris Verges <chrisv@cyberswitching.com>
  65 *
  66 * derived from ad5252.c
  67 * Copyright (c) 2006-2011 Michael Hennerich <hennerich@blackfin.uclinux.org>
  68 *
  69 * Licensed under the GPL-2 or later.
  70 */
  71
  72#include <linux/module.h>
  73#include <linux/device.h>
  74#include <linux/kernel.h>
  75#include <linux/init.h>
  76#include <linux/delay.h>
  77#include <linux/slab.h>
  78
  79#include "ad525x_dpot.h"
  80
  81/*
  82 * Client data (each client gets its own)
  83 */
  84
  85struct dpot_data {
  86        struct ad_dpot_bus_data bdata;
  87        struct mutex update_lock;
  88        unsigned rdac_mask;
  89        unsigned max_pos;
  90        unsigned long devid;
  91        unsigned uid;
  92        unsigned feat;
  93        unsigned wipers;
  94        u16 rdac_cache[MAX_RDACS];
  95        DECLARE_BITMAP(otp_en_mask, MAX_RDACS);
  96};
  97
  98static inline int dpot_read_d8(struct dpot_data *dpot)
  99{
 100        return dpot->bdata.bops->read_d8(dpot->bdata.client);
 101}
 102
 103static inline int dpot_read_r8d8(struct dpot_data *dpot, u8 reg)
 104{
 105        return dpot->bdata.bops->read_r8d8(dpot->bdata.client, reg);
 106}
 107
 108static inline int dpot_read_r8d16(struct dpot_data *dpot, u8 reg)
 109{
 110        return dpot->bdata.bops->read_r8d16(dpot->bdata.client, reg);
 111}
 112
 113static inline int dpot_write_d8(struct dpot_data *dpot, u8 val)
 114{
 115        return dpot->bdata.bops->write_d8(dpot->bdata.client, val);
 116}
 117
 118static inline int dpot_write_r8d8(struct dpot_data *dpot, u8 reg, u16 val)
 119{
 120        return dpot->bdata.bops->write_r8d8(dpot->bdata.client, reg, val);
 121}
 122
 123static inline int dpot_write_r8d16(struct dpot_data *dpot, u8 reg, u16 val)
 124{
 125        return dpot->bdata.bops->write_r8d16(dpot->bdata.client, reg, val);
 126}
 127
 128static s32 dpot_read_spi(struct dpot_data *dpot, u8 reg)
 129{
 130        unsigned ctrl = 0;
 131        int value;
 132
 133        if (!(reg & (DPOT_ADDR_EEPROM | DPOT_ADDR_CMD))) {
 134
 135                if (dpot->feat & F_RDACS_WONLY)
 136                        return dpot->rdac_cache[reg & DPOT_RDAC_MASK];
 137                if (dpot->uid == DPOT_UID(AD5291_ID) ||
 138                        dpot->uid == DPOT_UID(AD5292_ID) ||
 139                        dpot->uid == DPOT_UID(AD5293_ID)) {
 140
 141                        value = dpot_read_r8d8(dpot,
 142                                DPOT_AD5291_READ_RDAC << 2);
 143
 144                        if (dpot->uid == DPOT_UID(AD5291_ID))
 145                                value = value >> 2;
 146
 147                        return value;
 148                } else if (dpot->uid == DPOT_UID(AD5270_ID) ||
 149                        dpot->uid == DPOT_UID(AD5271_ID)) {
 150
 151                        value = dpot_read_r8d8(dpot,
 152                                DPOT_AD5270_1_2_4_READ_RDAC << 2);
 153
 154                        if (value < 0)
 155                                return value;
 156
 157                        if (dpot->uid == DPOT_UID(AD5271_ID))
 158                                value = value >> 2;
 159
 160                        return value;
 161                }
 162
 163                ctrl = DPOT_SPI_READ_RDAC;
 164        } else if (reg & DPOT_ADDR_EEPROM) {
 165                ctrl = DPOT_SPI_READ_EEPROM;
 166        }
 167
 168        if (dpot->feat & F_SPI_16BIT)
 169                return dpot_read_r8d8(dpot, ctrl);
 170        else if (dpot->feat & F_SPI_24BIT)
 171                return dpot_read_r8d16(dpot, ctrl);
 172
 173        return -EFAULT;
 174}
 175
 176static s32 dpot_read_i2c(struct dpot_data *dpot, u8 reg)
 177{
 178        int value;
 179        unsigned ctrl = 0;
 180        switch (dpot->uid) {
 181        case DPOT_UID(AD5246_ID):
 182        case DPOT_UID(AD5247_ID):
 183                return dpot_read_d8(dpot);
 184        case DPOT_UID(AD5245_ID):
 185        case DPOT_UID(AD5241_ID):
 186        case DPOT_UID(AD5242_ID):
 187        case DPOT_UID(AD5243_ID):
 188        case DPOT_UID(AD5248_ID):
 189        case DPOT_UID(AD5280_ID):
 190        case DPOT_UID(AD5282_ID):
 191                ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
 192                        0 : DPOT_AD5282_RDAC_AB;
 193                return dpot_read_r8d8(dpot, ctrl);
 194        case DPOT_UID(AD5170_ID):
 195        case DPOT_UID(AD5171_ID):
 196        case DPOT_UID(AD5273_ID):
 197                        return dpot_read_d8(dpot);
 198        case DPOT_UID(AD5172_ID):
 199        case DPOT_UID(AD5173_ID):
 200                ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
 201                        0 : DPOT_AD5172_3_A0;
 202                return dpot_read_r8d8(dpot, ctrl);
 203        case DPOT_UID(AD5272_ID):
 204        case DPOT_UID(AD5274_ID):
 205                        dpot_write_r8d8(dpot,
 206                                (DPOT_AD5270_1_2_4_READ_RDAC << 2), 0);
 207
 208                        value = dpot_read_r8d16(dpot,
 209                                DPOT_AD5270_1_2_4_RDAC << 2);
 210
 211                        if (value < 0)
 212                                return value;
 213                        /*
 214                         * AD5272/AD5274 returns high byte first, however
 215                         * underling smbus expects low byte first.
 216                         */
 217                        value = swab16(value);
 218
 219                        if (dpot->uid == DPOT_UID(AD5271_ID))
 220                                value = value >> 2;
 221                return value;
 222        default:
 223                if ((reg & DPOT_REG_TOL) || (dpot->max_pos > 256))
 224                        return dpot_read_r8d16(dpot, (reg & 0xF8) |
 225                                        ((reg & 0x7) << 1));
 226                else
 227                        return dpot_read_r8d8(dpot, reg);
 228        }
 229}
 230
 231static s32 dpot_read(struct dpot_data *dpot, u8 reg)
 232{
 233        if (dpot->feat & F_SPI)
 234                return dpot_read_spi(dpot, reg);
 235        else
 236                return dpot_read_i2c(dpot, reg);
 237}
 238
 239static s32 dpot_write_spi(struct dpot_data *dpot, u8 reg, u16 value)
 240{
 241        unsigned val = 0;
 242
 243        if (!(reg & (DPOT_ADDR_EEPROM | DPOT_ADDR_CMD | DPOT_ADDR_OTP))) {
 244                if (dpot->feat & F_RDACS_WONLY)
 245                        dpot->rdac_cache[reg & DPOT_RDAC_MASK] = value;
 246
 247                if (dpot->feat & F_AD_APPDATA) {
 248                        if (dpot->feat & F_SPI_8BIT) {
 249                                val = ((reg & DPOT_RDAC_MASK) <<
 250                                        DPOT_MAX_POS(dpot->devid)) |
 251                                        value;
 252                                return dpot_write_d8(dpot, val);
 253                        } else if (dpot->feat & F_SPI_16BIT) {
 254                                val = ((reg & DPOT_RDAC_MASK) <<
 255                                        DPOT_MAX_POS(dpot->devid)) |
 256                                        value;
 257                                return dpot_write_r8d8(dpot, val >> 8,
 258                                        val & 0xFF);
 259                        } else
 260                                BUG();
 261                } else {
 262                        if (dpot->uid == DPOT_UID(AD5291_ID) ||
 263                                dpot->uid == DPOT_UID(AD5292_ID) ||
 264                                dpot->uid == DPOT_UID(AD5293_ID)) {
 265
 266                                dpot_write_r8d8(dpot, DPOT_AD5291_CTRLREG << 2,
 267                                                DPOT_AD5291_UNLOCK_CMD);
 268
 269                                if (dpot->uid == DPOT_UID(AD5291_ID))
 270                                        value = value << 2;
 271
 272                                return dpot_write_r8d8(dpot,
 273                                        (DPOT_AD5291_RDAC << 2) |
 274                                        (value >> 8), value & 0xFF);
 275                        } else if (dpot->uid == DPOT_UID(AD5270_ID) ||
 276                                dpot->uid == DPOT_UID(AD5271_ID)) {
 277                                dpot_write_r8d8(dpot,
 278                                                DPOT_AD5270_1_2_4_CTRLREG << 2,
 279                                                DPOT_AD5270_1_2_4_UNLOCK_CMD);
 280
 281                                if (dpot->uid == DPOT_UID(AD5271_ID))
 282                                        value = value << 2;
 283
 284                                return dpot_write_r8d8(dpot,
 285                                        (DPOT_AD5270_1_2_4_RDAC << 2) |
 286                                        (value >> 8), value & 0xFF);
 287                        }
 288                        val = DPOT_SPI_RDAC | (reg & DPOT_RDAC_MASK);
 289                }
 290        } else if (reg & DPOT_ADDR_EEPROM) {
 291                val = DPOT_SPI_EEPROM | (reg & DPOT_RDAC_MASK);
 292        } else if (reg & DPOT_ADDR_CMD) {
 293                switch (reg) {
 294                case DPOT_DEC_ALL_6DB:
 295                        val = DPOT_SPI_DEC_ALL_6DB;
 296                        break;
 297                case DPOT_INC_ALL_6DB:
 298                        val = DPOT_SPI_INC_ALL_6DB;
 299                        break;
 300                case DPOT_DEC_ALL:
 301                        val = DPOT_SPI_DEC_ALL;
 302                        break;
 303                case DPOT_INC_ALL:
 304                        val = DPOT_SPI_INC_ALL;
 305                        break;
 306                }
 307        } else if (reg & DPOT_ADDR_OTP) {
 308                if (dpot->uid == DPOT_UID(AD5291_ID) ||
 309                        dpot->uid == DPOT_UID(AD5292_ID)) {
 310                        return dpot_write_r8d8(dpot,
 311                                DPOT_AD5291_STORE_XTPM << 2, 0);
 312                } else if (dpot->uid == DPOT_UID(AD5270_ID) ||
 313                        dpot->uid == DPOT_UID(AD5271_ID)) {
 314                        return dpot_write_r8d8(dpot,
 315                                DPOT_AD5270_1_2_4_STORE_XTPM << 2, 0);
 316                }
 317        } else
 318                BUG();
 319
 320        if (dpot->feat & F_SPI_16BIT)
 321                return dpot_write_r8d8(dpot, val, value);
 322        else if (dpot->feat & F_SPI_24BIT)
 323                return dpot_write_r8d16(dpot, val, value);
 324
 325        return -EFAULT;
 326}
 327
 328static s32 dpot_write_i2c(struct dpot_data *dpot, u8 reg, u16 value)
 329{
 330        /* Only write the instruction byte for certain commands */
 331        unsigned tmp = 0, ctrl = 0;
 332
 333        switch (dpot->uid) {
 334        case DPOT_UID(AD5246_ID):
 335        case DPOT_UID(AD5247_ID):
 336                return dpot_write_d8(dpot, value);
 337                break;
 338
 339        case DPOT_UID(AD5245_ID):
 340        case DPOT_UID(AD5241_ID):
 341        case DPOT_UID(AD5242_ID):
 342        case DPOT_UID(AD5243_ID):
 343        case DPOT_UID(AD5248_ID):
 344        case DPOT_UID(AD5280_ID):
 345        case DPOT_UID(AD5282_ID):
 346                ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
 347                        0 : DPOT_AD5282_RDAC_AB;
 348                return dpot_write_r8d8(dpot, ctrl, value);
 349                break;
 350        case DPOT_UID(AD5171_ID):
 351        case DPOT_UID(AD5273_ID):
 352                if (reg & DPOT_ADDR_OTP) {
 353                        tmp = dpot_read_d8(dpot);
 354                        if (tmp >> 6) /* Ready to Program? */
 355                                return -EFAULT;
 356                        ctrl = DPOT_AD5273_FUSE;
 357                }
 358                return dpot_write_r8d8(dpot, ctrl, value);
 359                break;
 360        case DPOT_UID(AD5172_ID):
 361        case DPOT_UID(AD5173_ID):
 362                ctrl = ((reg & DPOT_RDAC_MASK) == DPOT_RDAC0) ?
 363                        0 : DPOT_AD5172_3_A0;
 364                if (reg & DPOT_ADDR_OTP) {
 365                        tmp = dpot_read_r8d16(dpot, ctrl);
 366                        if (tmp >> 14) /* Ready to Program? */
 367                                return -EFAULT;
 368                        ctrl |= DPOT_AD5170_2_3_FUSE;
 369                }
 370                return dpot_write_r8d8(dpot, ctrl, value);
 371                break;
 372        case DPOT_UID(AD5170_ID):
 373                if (reg & DPOT_ADDR_OTP) {
 374                        tmp = dpot_read_r8d16(dpot, tmp);
 375                        if (tmp >> 14) /* Ready to Program? */
 376                                return -EFAULT;
 377                        ctrl = DPOT_AD5170_2_3_FUSE;
 378                }
 379                return dpot_write_r8d8(dpot, ctrl, value);
 380                break;
 381        case DPOT_UID(AD5272_ID):
 382        case DPOT_UID(AD5274_ID):
 383                dpot_write_r8d8(dpot, DPOT_AD5270_1_2_4_CTRLREG << 2,
 384                                DPOT_AD5270_1_2_4_UNLOCK_CMD);
 385
 386                if (reg & DPOT_ADDR_OTP)
 387                        return dpot_write_r8d8(dpot,
 388                                        DPOT_AD5270_1_2_4_STORE_XTPM << 2, 0);
 389
 390                if (dpot->uid == DPOT_UID(AD5274_ID))
 391                        value = value << 2;
 392
 393                return dpot_write_r8d8(dpot, (DPOT_AD5270_1_2_4_RDAC << 2) |
 394                                       (value >> 8), value & 0xFF);
 395                break;
 396        default:
 397                if (reg & DPOT_ADDR_CMD)
 398                        return dpot_write_d8(dpot, reg);
 399
 400                if (dpot->max_pos > 256)
 401                        return dpot_write_r8d16(dpot, (reg & 0xF8) |
 402                                                ((reg & 0x7) << 1), value);
 403                else
 404                        /* All other registers require instruction + data bytes */
 405                        return dpot_write_r8d8(dpot, reg, value);
 406        }
 407}
 408
 409static s32 dpot_write(struct dpot_data *dpot, u8 reg, u16 value)
 410{
 411        if (dpot->feat & F_SPI)
 412                return dpot_write_spi(dpot, reg, value);
 413        else
 414                return dpot_write_i2c(dpot, reg, value);
 415}
 416
 417/* sysfs functions */
 418
 419static ssize_t sysfs_show_reg(struct device *dev,
 420                              struct device_attribute *attr,
 421                              char *buf, u32 reg)
 422{
 423        struct dpot_data *data = dev_get_drvdata(dev);
 424        s32 value;
 425
 426        if (reg & DPOT_ADDR_OTP_EN)
 427                return sprintf(buf, "%s\n",
 428                        test_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask) ?
 429                        "enabled" : "disabled");
 430
 431
 432        mutex_lock(&data->update_lock);
 433        value = dpot_read(data, reg);
 434        mutex_unlock(&data->update_lock);
 435
 436        if (value < 0)
 437                return -EINVAL;
 438        /*
 439         * Let someone else deal with converting this ...
 440         * the tolerance is a two-byte value where the MSB
 441         * is a sign + integer value, and the LSB is a
 442         * decimal value.  See page 18 of the AD5258
 443         * datasheet (Rev. A) for more details.
 444         */
 445
 446        if (reg & DPOT_REG_TOL)
 447                return sprintf(buf, "0x%04x\n", value & 0xFFFF);
 448        else
 449                return sprintf(buf, "%u\n", value & data->rdac_mask);
 450}
 451
 452static ssize_t sysfs_set_reg(struct device *dev,
 453                             struct device_attribute *attr,
 454                             const char *buf, size_t count, u32 reg)
 455{
 456        struct dpot_data *data = dev_get_drvdata(dev);
 457        unsigned long value;
 458        int err;
 459
 460        if (reg & DPOT_ADDR_OTP_EN) {
 461                if (!strncmp(buf, "enabled", sizeof("enabled")))
 462                        set_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask);
 463                else
 464                        clear_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask);
 465
 466                return count;
 467        }
 468
 469        if ((reg & DPOT_ADDR_OTP) &&
 470                !test_bit(DPOT_RDAC_MASK & reg, data->otp_en_mask))
 471                return -EPERM;
 472
 473        err = strict_strtoul(buf, 10, &value);
 474        if (err)
 475                return err;
 476
 477        if (value > data->rdac_mask)
 478                value = data->rdac_mask;
 479
 480        mutex_lock(&data->update_lock);
 481        dpot_write(data, reg, value);
 482        if (reg & DPOT_ADDR_EEPROM)
 483                msleep(26);     /* Sleep while the EEPROM updates */
 484        else if (reg & DPOT_ADDR_OTP)
 485                msleep(400);    /* Sleep while the OTP updates */
 486        mutex_unlock(&data->update_lock);
 487
 488        return count;
 489}
 490
 491static ssize_t sysfs_do_cmd(struct device *dev,
 492                            struct device_attribute *attr,
 493                            const char *buf, size_t count, u32 reg)
 494{
 495        struct dpot_data *data = dev_get_drvdata(dev);
 496
 497        mutex_lock(&data->update_lock);
 498        dpot_write(data, reg, 0);
 499        mutex_unlock(&data->update_lock);
 500
 501        return count;
 502}
 503
 504/* ------------------------------------------------------------------------- */
 505
 506#define DPOT_DEVICE_SHOW(_name, _reg) static ssize_t \
 507show_##_name(struct device *dev, \
 508                          struct device_attribute *attr, char *buf) \
 509{ \
 510        return sysfs_show_reg(dev, attr, buf, _reg); \
 511}
 512
 513#define DPOT_DEVICE_SET(_name, _reg) static ssize_t \
 514set_##_name(struct device *dev, \
 515                         struct device_attribute *attr, \
 516                         const char *buf, size_t count) \
 517{ \
 518        return sysfs_set_reg(dev, attr, buf, count, _reg); \
 519}
 520
 521#define DPOT_DEVICE_SHOW_SET(name, reg) \
 522DPOT_DEVICE_SHOW(name, reg) \
 523DPOT_DEVICE_SET(name, reg) \
 524static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, show_##name, set_##name);
 525
 526#define DPOT_DEVICE_SHOW_ONLY(name, reg) \
 527DPOT_DEVICE_SHOW(name, reg) \
 528static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, show_##name, NULL);
 529
 530DPOT_DEVICE_SHOW_SET(rdac0, DPOT_ADDR_RDAC | DPOT_RDAC0);
 531DPOT_DEVICE_SHOW_SET(eeprom0, DPOT_ADDR_EEPROM | DPOT_RDAC0);
 532DPOT_DEVICE_SHOW_ONLY(tolerance0, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC0);
 533DPOT_DEVICE_SHOW_SET(otp0, DPOT_ADDR_OTP | DPOT_RDAC0);
 534DPOT_DEVICE_SHOW_SET(otp0en, DPOT_ADDR_OTP_EN | DPOT_RDAC0);
 535
 536DPOT_DEVICE_SHOW_SET(rdac1, DPOT_ADDR_RDAC | DPOT_RDAC1);
 537DPOT_DEVICE_SHOW_SET(eeprom1, DPOT_ADDR_EEPROM | DPOT_RDAC1);
 538DPOT_DEVICE_SHOW_ONLY(tolerance1, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC1);
 539DPOT_DEVICE_SHOW_SET(otp1, DPOT_ADDR_OTP | DPOT_RDAC1);
 540DPOT_DEVICE_SHOW_SET(otp1en, DPOT_ADDR_OTP_EN | DPOT_RDAC1);
 541
 542DPOT_DEVICE_SHOW_SET(rdac2, DPOT_ADDR_RDAC | DPOT_RDAC2);
 543DPOT_DEVICE_SHOW_SET(eeprom2, DPOT_ADDR_EEPROM | DPOT_RDAC2);
 544DPOT_DEVICE_SHOW_ONLY(tolerance2, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC2);
 545DPOT_DEVICE_SHOW_SET(otp2, DPOT_ADDR_OTP | DPOT_RDAC2);
 546DPOT_DEVICE_SHOW_SET(otp2en, DPOT_ADDR_OTP_EN | DPOT_RDAC2);
 547
 548DPOT_DEVICE_SHOW_SET(rdac3, DPOT_ADDR_RDAC | DPOT_RDAC3);
 549DPOT_DEVICE_SHOW_SET(eeprom3, DPOT_ADDR_EEPROM | DPOT_RDAC3);
 550DPOT_DEVICE_SHOW_ONLY(tolerance3, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC3);
 551DPOT_DEVICE_SHOW_SET(otp3, DPOT_ADDR_OTP | DPOT_RDAC3);
 552DPOT_DEVICE_SHOW_SET(otp3en, DPOT_ADDR_OTP_EN | DPOT_RDAC3);
 553
 554DPOT_DEVICE_SHOW_SET(rdac4, DPOT_ADDR_RDAC | DPOT_RDAC4);
 555DPOT_DEVICE_SHOW_SET(eeprom4, DPOT_ADDR_EEPROM | DPOT_RDAC4);
 556DPOT_DEVICE_SHOW_ONLY(tolerance4, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC4);
 557DPOT_DEVICE_SHOW_SET(otp4, DPOT_ADDR_OTP | DPOT_RDAC4);
 558DPOT_DEVICE_SHOW_SET(otp4en, DPOT_ADDR_OTP_EN | DPOT_RDAC4);
 559
 560DPOT_DEVICE_SHOW_SET(rdac5, DPOT_ADDR_RDAC | DPOT_RDAC5);
 561DPOT_DEVICE_SHOW_SET(eeprom5, DPOT_ADDR_EEPROM | DPOT_RDAC5);
 562DPOT_DEVICE_SHOW_ONLY(tolerance5, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC5);
 563DPOT_DEVICE_SHOW_SET(otp5, DPOT_ADDR_OTP | DPOT_RDAC5);
 564DPOT_DEVICE_SHOW_SET(otp5en, DPOT_ADDR_OTP_EN | DPOT_RDAC5);
 565
 566static const struct attribute *dpot_attrib_wipers[] = {
 567        &dev_attr_rdac0.attr,
 568        &dev_attr_rdac1.attr,
 569        &dev_attr_rdac2.attr,
 570        &dev_attr_rdac3.attr,
 571        &dev_attr_rdac4.attr,
 572        &dev_attr_rdac5.attr,
 573        NULL
 574};
 575
 576static const struct attribute *dpot_attrib_eeprom[] = {
 577        &dev_attr_eeprom0.attr,
 578        &dev_attr_eeprom1.attr,
 579        &dev_attr_eeprom2.attr,
 580        &dev_attr_eeprom3.attr,
 581        &dev_attr_eeprom4.attr,
 582        &dev_attr_eeprom5.attr,
 583        NULL
 584};
 585
 586static const struct attribute *dpot_attrib_otp[] = {
 587        &dev_attr_otp0.attr,
 588        &dev_attr_otp1.attr,
 589        &dev_attr_otp2.attr,
 590        &dev_attr_otp3.attr,
 591        &dev_attr_otp4.attr,
 592        &dev_attr_otp5.attr,
 593        NULL
 594};
 595
 596static const struct attribute *dpot_attrib_otp_en[] = {
 597        &dev_attr_otp0en.attr,
 598        &dev_attr_otp1en.attr,
 599        &dev_attr_otp2en.attr,
 600        &dev_attr_otp3en.attr,
 601        &dev_attr_otp4en.attr,
 602        &dev_attr_otp5en.attr,
 603        NULL
 604};
 605
 606static const struct attribute *dpot_attrib_tolerance[] = {
 607        &dev_attr_tolerance0.attr,
 608        &dev_attr_tolerance1.attr,
 609        &dev_attr_tolerance2.attr,
 610        &dev_attr_tolerance3.attr,
 611        &dev_attr_tolerance4.attr,
 612        &dev_attr_tolerance5.attr,
 613        NULL
 614};
 615
 616/* ------------------------------------------------------------------------- */
 617
 618#define DPOT_DEVICE_DO_CMD(_name, _cmd) static ssize_t \
 619set_##_name(struct device *dev, \
 620                         struct device_attribute *attr, \
 621                         const char *buf, size_t count) \
 622{ \
 623        return sysfs_do_cmd(dev, attr, buf, count, _cmd); \
 624} \
 625static DEVICE_ATTR(_name, S_IWUSR | S_IRUGO, NULL, set_##_name);
 626
 627DPOT_DEVICE_DO_CMD(inc_all, DPOT_INC_ALL);
 628DPOT_DEVICE_DO_CMD(dec_all, DPOT_DEC_ALL);
 629DPOT_DEVICE_DO_CMD(inc_all_6db, DPOT_INC_ALL_6DB);
 630DPOT_DEVICE_DO_CMD(dec_all_6db, DPOT_DEC_ALL_6DB);
 631
 632static struct attribute *ad525x_attributes_commands[] = {
 633        &dev_attr_inc_all.attr,
 634        &dev_attr_dec_all.attr,
 635        &dev_attr_inc_all_6db.attr,
 636        &dev_attr_dec_all_6db.attr,
 637        NULL
 638};
 639
 640static const struct attribute_group ad525x_group_commands = {
 641        .attrs = ad525x_attributes_commands,
 642};
 643
 644__devinit int ad_dpot_add_files(struct device *dev,
 645                unsigned features, unsigned rdac)
 646{
 647        int err = sysfs_create_file(&dev->kobj,
 648                dpot_attrib_wipers[rdac]);
 649        if (features & F_CMD_EEP)
 650                err |= sysfs_create_file(&dev->kobj,
 651                        dpot_attrib_eeprom[rdac]);
 652        if (features & F_CMD_TOL)
 653                err |= sysfs_create_file(&dev->kobj,
 654                        dpot_attrib_tolerance[rdac]);
 655        if (features & F_CMD_OTP) {
 656                err |= sysfs_create_file(&dev->kobj,
 657                        dpot_attrib_otp_en[rdac]);
 658                err |= sysfs_create_file(&dev->kobj,
 659                        dpot_attrib_otp[rdac]);
 660        }
 661
 662        if (err)
 663                dev_err(dev, "failed to register sysfs hooks for RDAC%d\n",
 664                        rdac);
 665
 666        return err;
 667}
 668
 669inline void ad_dpot_remove_files(struct device *dev,
 670                unsigned features, unsigned rdac)
 671{
 672        sysfs_remove_file(&dev->kobj,
 673                dpot_attrib_wipers[rdac]);
 674        if (features & F_CMD_EEP)
 675                sysfs_remove_file(&dev->kobj,
 676                        dpot_attrib_eeprom[rdac]);
 677        if (features & F_CMD_TOL)
 678                sysfs_remove_file(&dev->kobj,
 679                        dpot_attrib_tolerance[rdac]);
 680        if (features & F_CMD_OTP) {
 681                sysfs_remove_file(&dev->kobj,
 682                        dpot_attrib_otp_en[rdac]);
 683                sysfs_remove_file(&dev->kobj,
 684                        dpot_attrib_otp[rdac]);
 685        }
 686}
 687
 688int __devinit ad_dpot_probe(struct device *dev,
 689                struct ad_dpot_bus_data *bdata, unsigned long devid,
 690                            const char *name)
 691{
 692
 693        struct dpot_data *data;
 694        int i, err = 0;
 695
 696        data = kzalloc(sizeof(struct dpot_data), GFP_KERNEL);
 697        if (!data) {
 698                err = -ENOMEM;
 699                goto exit;
 700        }
 701
 702        dev_set_drvdata(dev, data);
 703        mutex_init(&data->update_lock);
 704
 705        data->bdata = *bdata;
 706        data->devid = devid;
 707
 708        data->max_pos = 1 << DPOT_MAX_POS(devid);
 709        data->rdac_mask = data->max_pos - 1;
 710        data->feat = DPOT_FEAT(devid);
 711        data->uid = DPOT_UID(devid);
 712        data->wipers = DPOT_WIPERS(devid);
 713
 714        for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
 715                if (data->wipers & (1 << i)) {
 716                        err = ad_dpot_add_files(dev, data->feat, i);
 717                        if (err)
 718                                goto exit_remove_files;
 719                        /* power-up midscale */
 720                        if (data->feat & F_RDACS_WONLY)
 721                                data->rdac_cache[i] = data->max_pos / 2;
 722                }
 723
 724        if (data->feat & F_CMD_INC)
 725                err = sysfs_create_group(&dev->kobj, &ad525x_group_commands);
 726
 727        if (err) {
 728                dev_err(dev, "failed to register sysfs hooks\n");
 729                goto exit_free;
 730        }
 731
 732        dev_info(dev, "%s %d-Position Digital Potentiometer registered\n",
 733                 name, data->max_pos);
 734
 735        return 0;
 736
 737exit_remove_files:
 738        for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
 739                if (data->wipers & (1 << i))
 740                        ad_dpot_remove_files(dev, data->feat, i);
 741
 742exit_free:
 743        kfree(data);
 744        dev_set_drvdata(dev, NULL);
 745exit:
 746        dev_err(dev, "failed to create client for %s ID 0x%lX\n",
 747                name, devid);
 748        return err;
 749}
 750EXPORT_SYMBOL(ad_dpot_probe);
 751
 752__devexit int ad_dpot_remove(struct device *dev)
 753{
 754        struct dpot_data *data = dev_get_drvdata(dev);
 755        int i;
 756
 757        for (i = DPOT_RDAC0; i < MAX_RDACS; i++)
 758                if (data->wipers & (1 << i))
 759                        ad_dpot_remove_files(dev, data->feat, i);
 760
 761        kfree(data);
 762
 763        return 0;
 764}
 765EXPORT_SYMBOL(ad_dpot_remove);
 766
 767
 768MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>, "
 769              "Michael Hennerich <hennerich@blackfin.uclinux.org>");
 770MODULE_DESCRIPTION("Digital potentiometer driver");
 771MODULE_LICENSE("GPL");
 772