drivers/staging/comedi/drivers/mpc624.c

   1 /*
   2     comedi/drivers/mpc624.c
   3     Hardware driver for a Micro/sys inc. MPC-624 PC/104 board
   4
   5     COMEDI - Linux Control and Measurement Device Interface
   6     Copyright (C) 2000 David A. Schleef <ds@schleef.org>
   7
   8     This program is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License as published by
  10     the Free Software Foundation; either version 2 of the License, or
  11     (at your option) any later version.
  12
  13     This program is distributed in the hope that it will be useful,
  14     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16     GNU General Public License for more details.
  17
  18     You should have received a copy of the GNU General Public License
  19     along with this program; if not, write to the Free Software
  20     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22 */
  23 /*
  24 Driver: mpc624
  25 Description: Micro/sys MPC-624 PC/104 board
  26 Devices: [Micro/sys] MPC-624 (mpc624)
  27 Author: Stanislaw Raczynski <sraczynski@op.pl>
  28 Updated: Thu, 15 Sep 2005 12:01:18 +0200
  29 Status: working
  30
  31     The Micro/sys MPC-624 board is based on the LTC2440 24-bit sigma-delta
  32     ADC chip.
  33
  34     Subdevices supported by the driver:
  35     - Analog In:   supported
  36     - Digital I/O: not supported
  37     - LEDs:        not supported
  38     - EEPROM:      not supported
  39
  40 Configuration Options:
  41   [0] - I/O base address
  42   [1] - conversion rate
  43         Conversion rate  RMS noise  Effective Number Of Bits
  44         0      3.52kHz        23uV                17
  45         1      1.76kHz       3.5uV                20
  46         2       880Hz         2uV                21.3
  47         3       440Hz        1.4uV               21.8
  48         4       220Hz         1uV                22.4
  49         5       110Hz        750uV               22.9
  50         6       55Hz         510nV               23.4
  51         7      27.5Hz        375nV                24
  52         8      13.75Hz       250nV               24.4
  53         9      6.875Hz       200nV               24.6
  54   [2] - voltage range
  55         0      -1.01V .. +1.01V
  56         1      -10.1V .. +10.1V
  57 */
  58
  59 #include "../comedidev.h"
  60
  61 #include <linux/ioport.h>
  62 #include <linux/delay.h>
  63
  64 /* Consecutive I/O port addresses */
  65 #define MPC624_SIZE             16
  66
  67 /* Offsets of different ports */
  68 #define MPC624_MASTER_CONTROL   0 /* not used */
  69 #define MPC624_GNMUXCH          1 /* Gain, Mux, Channel of ADC */
  70 #define MPC624_ADC              2 /* read/write to/from ADC */
  71 #define MPC624_EE               3 /* read/write to/from serial EEPROM via I2C */
  72 #define MPC624_LEDS             4 /* write to LEDs */
  73 #define MPC624_DIO              5 /* read/write to/from digital I/O ports */
  74 #define MPC624_IRQ_MASK         6 /* IRQ masking enable/disable */
  75
  76 /* Register bits' names */
  77 #define MPC624_ADBUSY           (1<<5)
  78 #define MPC624_ADSDO            (1<<4)
  79 #define MPC624_ADFO             (1<<3)
  80 #define MPC624_ADCS             (1<<2)
  81 #define MPC624_ADSCK            (1<<1)
  82 #define MPC624_ADSDI            (1<<0)
  83
  84 /* SDI Speed/Resolution Programming bits */
  85 #define MPC624_OSR4             (1<<31)
  86 #define MPC624_OSR3             (1<<30)
  87 #define MPC624_OSR2             (1<<29)
  88 #define MPC624_OSR1             (1<<28)
  89 #define MPC624_OSR0             (1<<27)
  90
  91 /* 32-bit output value bits' names */
  92 #define MPC624_EOC_BIT          (1<<31)
  93 #define MPC624_DMY_BIT          (1<<30)
  94 #define MPC624_SGN_BIT          (1<<29)
  95
  96 /* Conversion speeds */
  97 /* OSR4 OSR3 OSR2 OSR1 OSR0  Conversion rate  RMS noise  ENOB^
  98  *  X    0    0    0    1        3.52kHz        23uV      17
  99  *  X    0    0    1    0        1.76kHz       3.5uV      20
 100  *  X    0    0    1    1         880Hz         2uV      21.3
 101  *  X    0    1    0    0         440Hz        1.4uV     21.8
 102  *  X    0    1    0    1         220Hz         1uV      22.4
 103  *  X    0    1    1    0         110Hz        750uV     22.9
 104  *  X    0    1    1    1          55Hz        510nV     23.4
 105  *  X    1    0    0    0         27.5Hz       375nV      24
 106  *  X    1    0    0    1        13.75Hz       250nV     24.4
 107  *  X    1    1    1    1        6.875Hz       200nV     24.6
 108  *
 109  * ^ - Effective Number Of Bits
 110  */
 111
 112 #define MPC624_SPEED_3_52_kHz (MPC624_OSR4 | MPC624_OSR0)
 113 #define MPC624_SPEED_1_76_kHz (MPC624_OSR4 | MPC624_OSR1)
 114 #define MPC624_SPEED_880_Hz   (MPC624_OSR4 | MPC624_OSR1 | MPC624_OSR0)
 115 #define MPC624_SPEED_440_Hz   (MPC624_OSR4 | MPC624_OSR2)
 116 #define MPC624_SPEED_220_Hz   (MPC624_OSR4 | MPC624_OSR2 | MPC624_OSR0)
 117 #define MPC624_SPEED_110_Hz   (MPC624_OSR4 | MPC624_OSR2 | MPC624_OSR1)
 118 #define MPC624_SPEED_55_Hz \
 119         (MPC624_OSR4 | MPC624_OSR2 | MPC624_OSR1 | MPC624_OSR0)
 120 #define MPC624_SPEED_27_5_Hz  (MPC624_OSR4 | MPC624_OSR3)
 121 #define MPC624_SPEED_13_75_Hz (MPC624_OSR4 | MPC624_OSR3 | MPC624_OSR0)
 122 #define MPC624_SPEED_6_875_Hz \
 123         (MPC624_OSR4 | MPC624_OSR3 | MPC624_OSR2 | MPC624_OSR1 | MPC624_OSR0)
 124 /* -------------------------------------------------------------------------- */
 125 struct skel_private {
 126
 127         /*  set by mpc624_attach() from driver's parameters */
 128         unsigned long int ulConvertionRate;
 129 };
 130
 131 #define devpriv ((struct skel_private *)dev->private)
 132 /* -------------------------------------------------------------------------- */
 133 static const struct comedi_lrange range_mpc624_bipolar1 = {
 134         1,
 135         {
 136 /* BIP_RANGE(1.01)  this is correct, */
 137          /*  but my MPC-624 actually seems to have a range of 2.02 */
 138          BIP_RANGE(2.02)
 139          }
 140 };
 141
 142 static const struct comedi_lrange range_mpc624_bipolar10 = {
 143         1,
 144         {
 145 /* BIP_RANGE(10.1)   this is correct, */
 146          /*  but my MPC-624 actually seems to have a range of 20.2 */
 147          BIP_RANGE(20.2)
 148          }
 149 };
 150
 151 /* -------------------------------------------------------------------------- */
 152 static int mpc624_attach(struct comedi_device *dev,
 153                          struct comedi_devconfig *it);
 154 static int mpc624_detach(struct comedi_device *dev);
 155 /* -------------------------------------------------------------------------- */
 156 static struct comedi_driver driver_mpc624 = {
 157         .driver_name = "mpc624",
 158         .module = THIS_MODULE,
 159         .attach = mpc624_attach,
 160         .detach = mpc624_detach
 161 };
 162
 163 /* -------------------------------------------------------------------------- */
 164 static int mpc624_ai_rinsn(struct comedi_device *dev,
 165                            struct comedi_subdevice *s, struct comedi_insn *insn,
 166                            unsigned int *data);
 167 /* -------------------------------------------------------------------------- */
 168 static int mpc624_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 169 {
 170         struct comedi_subdevice *s;
 171         unsigned long iobase;
 172
 173         iobase = it->options[0];
 174         printk(KERN_INFO "comedi%d: mpc624 [0x%04lx, ", dev->minor, iobase);
 175         if (request_region(iobase, MPC624_SIZE, "mpc624") == NULL) {
 176                 printk(KERN_ERR "I/O port(s) in use\n");
 177                 return -EIO;
 178         }
 179
 180         dev->iobase = iobase;
 181         dev->board_name = "mpc624";
 182
 183         /*  Private structure initialization */
 184         if (alloc_private(dev, sizeof(struct skel_private)) < 0)
 185                 return -ENOMEM;
 186
 187         switch (it->options[1]) {
 188         case 0:
 189                 devpriv->ulConvertionRate = MPC624_SPEED_3_52_kHz;
 190                 printk(KERN_INFO "3.52 kHz, ");
 191                 break;
 192         case 1:
 193                 devpriv->ulConvertionRate = MPC624_SPEED_1_76_kHz;
 194                 printk(KERN_INFO "1.76 kHz, ");
 195                 break;
 196         case 2:
 197                 devpriv->ulConvertionRate = MPC624_SPEED_880_Hz;
 198                 printk(KERN_INFO "880 Hz, ");
 199                 break;
 200         case 3:
 201                 devpriv->ulConvertionRate = MPC624_SPEED_440_Hz;
 202                 printk(KERN_INFO "440 Hz, ");
 203                 break;
 204         case 4:
 205                 devpriv->ulConvertionRate = MPC624_SPEED_220_Hz;
 206                 printk(KERN_INFO "220 Hz, ");
 207                 break;
 208         case 5:
 209                 devpriv->ulConvertionRate = MPC624_SPEED_110_Hz;
 210                 printk(KERN_INFO "110 Hz, ");
 211                 break;
 212         case 6:
 213                 devpriv->ulConvertionRate = MPC624_SPEED_55_Hz;
 214                 printk(KERN_INFO "55 Hz, ");
 215                 break;
 216         case 7:
 217                 devpriv->ulConvertionRate = MPC624_SPEED_27_5_Hz;
 218                 printk(KERN_INFO "27.5 Hz, ");
 219                 break;
 220         case 8:
 221                 devpriv->ulConvertionRate = MPC624_SPEED_13_75_Hz;
 222                 printk(KERN_INFO "13.75 Hz, ");
 223                 break;
 224         case 9:
 225                 devpriv->ulConvertionRate = MPC624_SPEED_6_875_Hz;
 226                 printk(KERN_INFO "6.875 Hz, ");
 227                 break;
 228         default:
 229                 printk
 230                     (KERN_ERR "illegal conversion rate setting!"
 231                         " Valid numbers are 0..9. Using 9 => 6.875 Hz, ");
 232                 devpriv->ulConvertionRate = MPC624_SPEED_3_52_kHz;
 233         }
 234
 235         /*  Subdevices structures */
 236         if (alloc_subdevices(dev, 1) < 0)
 237                 return -ENOMEM;
 238
 239         s = dev->subdevices + 0;
 240         s->type = COMEDI_SUBD_AI;
 241         s->subdev_flags = SDF_READABLE | SDF_DIFF;
 242         s->n_chan = 8;
 243         switch (it->options[1]) {
 244         default:
 245                 s->maxdata = 0x3FFFFFFF;
 246                 printk(KERN_INFO "30 bit, ");
 247         }
 248
 249         switch (it->options[1]) {
 250         case 0:
 251                 s->range_table = &range_mpc624_bipolar1;
 252                 printk(KERN_INFO "1.01V]: ");
 253                 break;
 254         default:
 255                 s->range_table = &range_mpc624_bipolar10;
 256                 printk(KERN_INFO "10.1V]: ");
 257         }
 258         s->len_chanlist = 1;
 259         s->insn_read = mpc624_ai_rinsn;
 260
 261         printk(KERN_INFO "attached\n");
 262
 263         return 1;
 264 }
 265
 266 static int mpc624_detach(struct comedi_device *dev)
 267 {
 268         printk(KERN_INFO "comedi%d: mpc624: remove\n", dev->minor);
 269
 270         if (dev->iobase)
 271                 release_region(dev->iobase, MPC624_SIZE);
 272
 273         return 0;
 274 }
 275
 276 /* Timeout 200ms */
 277 #define TIMEOUT 200
 278
 279 static int mpc624_ai_rinsn(struct comedi_device *dev,
 280                            struct comedi_subdevice *s, struct comedi_insn *insn,
 281                            unsigned int *data)
 282 {
 283         int n, i;
 284         unsigned long int data_in, data_out;
 285         unsigned char ucPort;
 286
 287         /*
 288          *  WARNING:
 289          *  We always write 0 to GNSWA bit, so the channel range is +-/10.1Vdc
 290          */
 291         outb(insn->chanspec, dev->iobase + MPC624_GNMUXCH);
 292 /* printk("Channel %d:\n", insn->chanspec); */
 293         if (!insn->n) {
 294                 printk(KERN_INFO "MPC624: Warning, no data to acquire\n");
 295                 return 0;
 296         }
 297
 298         for (n = 0; n < insn->n; n++) {
 299                 /*  Trigger the conversion */
 300                 outb(MPC624_ADSCK, dev->iobase + MPC624_ADC);
 301                 udelay(1);
 302                 outb(MPC624_ADCS | MPC624_ADSCK, dev->iobase + MPC624_ADC);
 303                 udelay(1);
 304                 outb(0, dev->iobase + MPC624_ADC);
 305                 udelay(1);
 306
 307                 /*  Wait for the conversion to end */
 308                 for (i = 0; i < TIMEOUT; i++) {
 309                         ucPort = inb(dev->iobase + MPC624_ADC);
 310                         if (ucPort & MPC624_ADBUSY)
 311                                 udelay(1000);
 312                         else
 313                                 break;
 314                 }
 315                 if (i == TIMEOUT) {
 316                         printk(KERN_ERR "MPC624: timeout (%dms)\n", TIMEOUT);
 317                         data[n] = 0;
 318                         return -ETIMEDOUT;
 319                 }
 320                 /*  Start reading data */
 321                 data_in = 0;
 322                 data_out = devpriv->ulConvertionRate;
 323                 udelay(1);
 324                 for (i = 0; i < 32; i++) {
 325                         /*  Set the clock low */
 326                         outb(0, dev->iobase + MPC624_ADC);
 327                         udelay(1);
 328
 329                         if (data_out & (1 << 31)) { /*  the next bit is a 1 */
 330                                 /*  Set the ADSDI line (send to MPC624) */
 331                                 outb(MPC624_ADSDI, dev->iobase + MPC624_ADC);
 332                                 udelay(1);
 333                                 /*  Set the clock high */
 334                                 outb(MPC624_ADSCK | MPC624_ADSDI,
 335                                      dev->iobase + MPC624_ADC);
 336                         } else {        /*  the next bit is a 0 */
 337
 338                                 /*  Set the ADSDI line (send to MPC624) */
 339                                 outb(0, dev->iobase + MPC624_ADC);
 340                                 udelay(1);
 341                                 /*  Set the clock high */
 342                                 outb(MPC624_ADSCK, dev->iobase + MPC624_ADC);
 343                         }
 344                         /*  Read ADSDO on high clock (receive from MPC624) */
 345                         udelay(1);
 346                         data_in <<= 1;
 347                         data_in |=
 348                             (inb(dev->iobase + MPC624_ADC) & MPC624_ADSDO) >> 4;
 349                         udelay(1);
 350
 351                         data_out <<= 1;
 352                 }
 353
 354                 /*
 355                  *  Received 32-bit long value consist of:
 356                  *    31: EOC -
 357                  *          (End Of Transmission) bit - should be 0
 358                  *    30: DMY
 359                  *          (Dummy) bit - should be 0
 360                  *    29: SIG
 361                  *          (Sign) bit- 1 if the voltage is positive,
 362                  *                      0 if negative
 363                  *    28: MSB
 364                  *          (Most Significant Bit) - the first bit of
 365                  *                                   the conversion result
 366                  *    ....
 367                  *    05: LSB
 368                  *          (Least Significant Bit)- the last bit of the
 369                  *                                   conversion result
 370                  *    04-00: sub-LSB
 371                  *          - sub-LSBs are basically noise, but when
 372                  *            averaged properly, they can increase conversion
 373                  *            precision up to 29 bits; they can be discarded
 374                  *            without loss of resolution.
 375                  */
 376
 377                 if (data_in & MPC624_EOC_BIT)
 378                         printk(KERN_INFO "MPC624:EOC bit is set (data_in=%lu)!",
 379                                data_in);
 380                 if (data_in & MPC624_DMY_BIT)
 381                         printk(KERN_INFO "MPC624:DMY bit is set (data_in=%lu)!",
 382                                data_in);
 383                 if (data_in & MPC624_SGN_BIT) { /* Volatge is positive */
 384                         /*
 385                          * comedi operates on unsigned numbers, so mask off EOC
 386                          * and DMY and don't clear the SGN bit
 387                          */
 388                         data_in &= 0x3FFFFFFF;
 389                         data[n] = data_in;
 390                 } else { /*  The voltage is negative */
 391                         /*
 392                          * data_in contains a number in 30-bit two's complement
 393                          * code and we must deal with it
 394                          */
 395                         data_in |= MPC624_SGN_BIT;
 396                         data_in = ~data_in;
 397                         data_in += 1;
 398                         data_in &= ~(MPC624_EOC_BIT | MPC624_DMY_BIT);
 399                         /*  clear EOC and DMY bits */
 400                         data_in = 0x20000000 - data_in;
 401                         data[n] = data_in;
 402                 }
 403         }
 404
 405         /*  Return the number of samples read/written */
 406         return n;
 407 }
 408
 409 static int __init driver_mpc624_init_module(void)
 410 {
 411         return comedi_driver_register(&driver_mpc624);
 412 }
 413
 414 static void __exit driver_mpc624_cleanup_module(void)
 415 {
 416         comedi_driver_unregister(&driver_mpc624);
 417 }
 418
 419 module_init(driver_mpc624_init_module);
 420 module_exit(driver_mpc624_cleanup_module);
 421
 422 MODULE_AUTHOR("Comedi http://www.comedi.org");
 423 MODULE_DESCRIPTION("Comedi low-level driver");
 424 MODULE_LICENSE("GPL");