Pileus Git - ~andy/linux/blob - drivers/staging/comedi/drivers/dt9812.c

   1 /*
   2  * comedi/drivers/dt9812.c
   3  *   COMEDI driver for DataTranslation DT9812 USB module
   4  *
   5  * Copyright (C) 2005 Anders Blomdell <anders.blomdell@control.lth.se>
   6  *
   7  * COMEDI - Linux Control and Measurement Device Interface
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13
  14  *  This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22  *
  23  */
  24
  25 /*
  26 Driver: dt9812
  27 Description: Data Translation DT9812 USB module
  28 Author: anders.blomdell@control.lth.se (Anders Blomdell)
  29 Status: in development
  30 Devices: [Data Translation] DT9812 (dt9812)
  31 Updated: Sun Nov 20 20:18:34 EST 2005
  32
  33 This driver works, but bulk transfers not implemented. Might be a starting point
  34 for someone else. I found out too late that USB has too high latencies (>1 ms)
  35 for my needs.
  36 */
  37
  38 /*
  39  * Nota Bene:
  40  *   1. All writes to command pipe has to be 32 bytes (ISP1181B SHRTP=0 ?)
  41  *   2. The DDK source (as of sep 2005) is in error regarding the
  42  *      input MUX bits (example code says P4, but firmware schematics
  43  *      says P1).
  44  */
  45
  46 #include <linux/kernel.h>
  47 #include <linux/errno.h>
  48 #include <linux/init.h>
  49 #include <linux/slab.h>
  50 #include <linux/module.h>
  51 #include <linux/kref.h>
  52 #include <linux/uaccess.h>
  53 #include <linux/usb.h>
  54
  55 #include "../comedidev.h"
  56 #include "dt9812.h"
  57
  58 #define DT9812_NUM_SLOTS        16
  59
  60 static DECLARE_MUTEX(dt9812_mutex);
  61
  62 static struct usb_device_id dt9812_table[] = {
  63         {USB_DEVICE(0x0867, 0x9812)},
  64         { }                     /* Terminating entry */
  65 };
  66
  67 MODULE_DEVICE_TABLE(usb, dt9812_table);
  68
  69 typedef struct usb_dt9812 {
  70         struct slot_dt9812 *slot;
  71         struct usb_device *udev;
  72         struct usb_interface *interface;
  73         u16 vendor;
  74         u16 product;
  75         u16 device;
  76         u32 serial;
  77         struct {
  78                 __u8 addr;
  79                 size_t size;
  80         } message_pipe, command_write, command_read, write_stream, read_stream;
  81         struct kref kref;
  82         u16 analog_out_shadow[2];
  83         u8 digital_out_shadow;
  84 } usb_dt9812_t;
  85
  86 typedef struct comedi_dt9812 {
  87         struct slot_dt9812 *slot;
  88         u32 serial;
  89 } comedi_dt9812_t;
  90
  91 typedef struct slot_dt9812 {
  92         struct semaphore mutex;
  93         u32 serial;
  94         usb_dt9812_t *usb;
  95         comedi_dt9812_t *comedi;
  96 } slot_dt9812_t;
  97
  98 static const comedi_lrange dt9812_10_ain_range = { 1, {
  99                         BIP_RANGE(10),
 100         }
 101 };
 102
 103 static const comedi_lrange dt9812_2pt5_ain_range = { 1, {
 104                         UNI_RANGE(2.5),
 105         }
 106 };
 107
 108 static const comedi_lrange dt9812_10_aout_range = { 1, {
 109                         BIP_RANGE(10),
 110         }
 111 };
 112
 113 static const comedi_lrange dt9812_2pt5_aout_range = { 1, {
 114                         UNI_RANGE(2.5),
 115         }
 116 };
 117
 118 static slot_dt9812_t dt9812[DT9812_NUM_SLOTS];
 119
 120 /* Useful shorthand access to private data */
 121 #define devpriv ((comedi_dt9812_t *)dev->private)
 122
 123 static inline usb_dt9812_t *to_dt9812_dev(struct kref *d)
 124 {
 125         return container_of(d, usb_dt9812_t, kref);
 126 }
 127
 128 static void dt9812_delete(struct kref *kref)
 129 {
 130         usb_dt9812_t *dev = to_dt9812_dev(kref);
 131
 132         usb_put_dev(dev->udev);
 133         kfree(dev);
 134 }
 135
 136 static int dt9812_read_info(usb_dt9812_t *dev, int offset, void *buf,
 137                             size_t buf_size)
 138 {
 139         dt9812_usb_cmd_t cmd;
 140         int count, retval;
 141
 142         cmd.cmd = cpu_to_le32(DT9812_R_FLASH_DATA);
 143         cmd.u.flash_data_info.address =
 144                 cpu_to_le16(DT9812_DIAGS_BOARD_INFO_ADDR + offset);
 145         cmd.u.flash_data_info.numbytes = cpu_to_le16(buf_size);
 146
 147         /* DT9812 only responds to 32 byte writes!! */
 148         count = 32;
 149         retval = usb_bulk_msg(dev->udev,
 150                               usb_sndbulkpipe(dev->udev,
 151                                               dev->command_write.addr),
 152                               &cmd, 32, &count, HZ * 1);
 153         if (retval)
 154                 return retval;
 155         retval = usb_bulk_msg(dev->udev,
 156                               usb_rcvbulkpipe(dev->udev,
 157                                               dev->command_read.addr),
 158                               buf, buf_size, &count, HZ * 1);
 159         return retval;
 160 }
 161
 162 static int dt9812_read_multiple_registers(usb_dt9812_t *dev, int reg_count,
 163                                           u8 *address, u8 *value)
 164 {
 165         dt9812_usb_cmd_t cmd;
 166         int i, count, retval;
 167
 168         cmd.cmd = cpu_to_le32(DT9812_R_MULTI_BYTE_REG);
 169         cmd.u.read_multi_info.count = reg_count;
 170         for (i = 0; i < reg_count; i++)
 171                 cmd.u.read_multi_info.address[i] = address[i];
 172
 173         /* DT9812 only responds to 32 byte writes!! */
 174         count = 32;
 175         retval = usb_bulk_msg(dev->udev,
 176                               usb_sndbulkpipe(dev->udev,
 177                                               dev->command_write.addr),
 178                               &cmd, 32, &count, HZ * 1);
 179         if (retval)
 180                 return retval;
 181         retval = usb_bulk_msg(dev->udev,
 182                               usb_rcvbulkpipe(dev->udev,
 183                                               dev->command_read.addr),
 184                               value, reg_count, &count, HZ * 1);
 185         return retval;
 186 }
 187
 188 static int dt9812_write_multiple_registers(usb_dt9812_t *dev, int reg_count,
 189                                            u8 *address, u8 *value)
 190 {
 191         dt9812_usb_cmd_t cmd;
 192         int i, count, retval;
 193
 194         cmd.cmd = cpu_to_le32(DT9812_W_MULTI_BYTE_REG);
 195         cmd.u.read_multi_info.count = reg_count;
 196         for (i = 0; i < reg_count; i++) {
 197                 cmd.u.write_multi_info.write[i].address = address[i];
 198                 cmd.u.write_multi_info.write[i].value = value[i];
 199         }
 200         /* DT9812 only responds to 32 byte writes!! */
 201         retval = usb_bulk_msg(dev->udev,
 202                               usb_sndbulkpipe(dev->udev,
 203                                               dev->command_write.addr),
 204                               &cmd, 32, &count, HZ * 1);
 205         return retval;
 206 }
 207
 208 static int dt9812_rmw_multiple_registers(usb_dt9812_t *dev, int reg_count,
 209                                          dt9812_rmw_byte_t rmw[])
 210 {
 211         dt9812_usb_cmd_t cmd;
 212         int i, count, retval;
 213
 214         cmd.cmd = cpu_to_le32(DT9812_RMW_MULTI_BYTE_REG);
 215         cmd.u.rmw_multi_info.count = reg_count;
 216         for (i = 0; i < reg_count; i++)
 217                 cmd.u.rmw_multi_info.rmw[i] = rmw[i];
 218
 219         /* DT9812 only responds to 32 byte writes!! */
 220         retval = usb_bulk_msg(dev->udev,
 221                               usb_sndbulkpipe(dev->udev,
 222                                               dev->command_write.addr),
 223                               &cmd, 32, &count, HZ * 1);
 224         return retval;
 225 }
 226
 227 static int dt9812_digital_in(slot_dt9812_t *slot, u8 *bits)
 228 {
 229         int result = -ENODEV;
 230
 231         down(&slot->mutex);
 232         if (slot->usb) {
 233                 u8 reg[2] = { F020_SFR_P3, F020_SFR_P1 };
 234                 u8 value[2];
 235
 236                 result = dt9812_read_multiple_registers(slot->usb, 2, reg,
 237                                                         value);
 238                 if (result == 0) {
 239                         /*
 240                          * bits 0-6 in F020_SFR_P3 are bits 0-6 in the digital
 241                          * input port bit 3 in F020_SFR_P1 is bit 7 in the
 242                          * digital input port
 243                          */
 244                         *bits = (value[0] & 0x7f) | ((value[1] & 0x08) << 4);
 245                         /* printk("%2.2x, %2.2x -> %2.2x\n",
 246                                   value[0], value[1], *bits); */
 247                 }
 248         }
 249         up(&slot->mutex);
 250
 251         return result;
 252 }
 253
 254 static int dt9812_digital_out(slot_dt9812_t *slot, u8 bits)
 255 {
 256         int result = -ENODEV;
 257
 258         down(&slot->mutex);
 259         if (slot->usb) {
 260                 u8 reg[1];
 261                 u8 value[1];
 262
 263                 reg[0] = F020_SFR_P2;
 264                 value[0] = bits;
 265                 result = dt9812_write_multiple_registers(slot->usb, 1, reg,
 266                                                          value);
 267                 slot->usb->digital_out_shadow = bits;
 268         }
 269         up(&slot->mutex);
 270         return result;
 271 }
 272
 273 static int dt9812_digital_out_shadow(slot_dt9812_t *slot, u8 *bits)
 274 {
 275         int result = -ENODEV;
 276
 277         down(&slot->mutex);
 278         if (slot->usb) {
 279                 *bits = slot->usb->digital_out_shadow;
 280                 result = 0;
 281         }
 282         up(&slot->mutex);
 283         return result;
 284 }
 285
 286 static void dt9812_configure_mux(usb_dt9812_t *dev, dt9812_rmw_byte_t *rmw,
 287                                  int channel)
 288 {
 289         if (dev->device == DT9812_DEVID_DT9812_10) {
 290                 /* In the DT9812/10V MUX is selected by P1.5-7 */
 291                 rmw->address = F020_SFR_P1;
 292                 rmw->and_mask = 0xe0;
 293                 rmw->or_value = channel << 5;
 294         } else {
 295                 /* In the DT9812/2.5V, internal mux is selected by bits 0:2 */
 296                 rmw->address = F020_SFR_AMX0SL;
 297                 rmw->and_mask = 0xff;
 298                 rmw->or_value = channel & 0x07;
 299         }
 300 }
 301
 302 static void dt9812_configure_gain(usb_dt9812_t *dev, dt9812_rmw_byte_t *rmw,
 303                                   dt9812_gain_t gain)
 304 {
 305         if (dev->device == DT9812_DEVID_DT9812_10) {
 306                 /* In the DT9812/10V, there is an external gain of 0.5 */
 307                 gain <<= 1;
 308         }
 309
 310         rmw->address = F020_SFR_ADC0CF;
 311         rmw->and_mask = F020_MASK_ADC0CF_AMP0GN2 |
 312                         F020_MASK_ADC0CF_AMP0GN1 |
 313                         F020_MASK_ADC0CF_AMP0GN0;
 314         switch (gain) {
 315                 /*
 316                  * 000 -> Gain =  1
 317                  * 001 -> Gain =  2
 318                  * 010 -> Gain =  4
 319                  * 011 -> Gain =  8
 320                  * 10x -> Gain = 16
 321                  * 11x -> Gain =  0.5
 322                  */
 323         case DT9812_GAIN_0PT5:
 324                 rmw->or_value = F020_MASK_ADC0CF_AMP0GN2 ||
 325                                 F020_MASK_ADC0CF_AMP0GN1;
 326                 break;
 327         case DT9812_GAIN_1:
 328                 rmw->or_value = 0x00;
 329                 break;
 330         case DT9812_GAIN_2:
 331                 rmw->or_value = F020_MASK_ADC0CF_AMP0GN0;
 332                 break;
 333         case DT9812_GAIN_4:
 334                 rmw->or_value = F020_MASK_ADC0CF_AMP0GN1;
 335                 break;
 336         case DT9812_GAIN_8:
 337                 rmw->or_value = F020_MASK_ADC0CF_AMP0GN1 ||
 338                                 F020_MASK_ADC0CF_AMP0GN0;
 339                 break;
 340         case DT9812_GAIN_16:
 341                 rmw->or_value = F020_MASK_ADC0CF_AMP0GN2;
 342                 break;
 343         default:
 344                 err("Illegal gain %d\n", gain);
 345
 346         }
 347 }
 348
 349 static int dt9812_analog_in(slot_dt9812_t *slot, int channel, u16 *value,
 350                             dt9812_gain_t gain)
 351 {
 352         dt9812_rmw_byte_t rmw[3];
 353         u8 reg[3] = {
 354                 F020_SFR_ADC0CN,
 355                 F020_SFR_ADC0H,
 356                 F020_SFR_ADC0L
 357         };
 358         u8 val[3];
 359         int result = -ENODEV;
 360
 361         down(&slot->mutex);
 362         if (!slot->usb)
 363                 goto exit;
 364
 365         /* 1 select the gain */
 366         dt9812_configure_gain(slot->usb, &rmw[0], gain);
 367
 368         /* 2 set the MUX to select the channel */
 369         dt9812_configure_mux(slot->usb, &rmw[1], channel);
 370
 371         /* 3 start conversion */
 372         rmw[2].address = F020_SFR_ADC0CN;
 373         rmw[2].and_mask = 0xff;
 374         rmw[2].or_value = F020_MASK_ADC0CN_AD0EN | F020_MASK_ADC0CN_AD0BUSY;
 375
 376         result = dt9812_rmw_multiple_registers(slot->usb, 3, rmw);
 377         if (result)
 378                 goto exit;
 379
 380         /* read the status and ADC */
 381         result = dt9812_read_multiple_registers(slot->usb, 3, reg, val);
 382         if (result)
 383                 goto exit;
 384         /*
 385          * An ADC conversion takes 16 SAR clocks cycles, i.e. about 9us.
 386          * Therefore, between the instant that AD0BUSY was set via
 387          * dt9812_rmw_multiple_registers and the read of AD0BUSY via
 388          * dt9812_read_multiple_registers, the conversion should be complete
 389          * since these two operations require two USB transactions each taking
 390          * at least a millisecond to complete.  However, lets make sure that
 391          * conversion is finished.
 392          */
 393         if ((val[0] & (F020_MASK_ADC0CN_AD0INT | F020_MASK_ADC0CN_AD0BUSY)) ==
 394             F020_MASK_ADC0CN_AD0INT) {
 395                 switch (slot->usb->device) {
 396                 case DT9812_DEVID_DT9812_10:
 397                         /*
 398                          * For DT9812-10V the personality module set the
 399                          * encoding to 2's complement. Hence, convert it before
 400                          * returning it
 401                          */
 402                         *value = ((val[1] << 8) | val[2]) + 0x800;
 403                         break;
 404                 case DT9812_DEVID_DT9812_2PT5:
 405                         *value = (val[1] << 8) | val[2];
 406                         break;
 407                 }
 408         }
 409
 410 exit:
 411         up(&slot->mutex);
 412         return result;
 413 }
 414
 415 static int dt9812_analog_out_shadow(slot_dt9812_t *slot, int channel,
 416                                     u16 *value)
 417 {
 418         int result = -ENODEV;
 419
 420         down(&slot->mutex);
 421         if (slot->usb) {
 422                 *value = slot->usb->analog_out_shadow[channel];
 423                 result = 0;
 424         }
 425         up(&slot->mutex);
 426
 427         return result;
 428 }
 429
 430 static int dt9812_analog_out(slot_dt9812_t *slot, int channel, u16 value)
 431 {
 432         int result = -ENODEV;
 433
 434         down(&slot->mutex);
 435         if (slot->usb) {
 436                 dt9812_rmw_byte_t rmw[3];
 437
 438                 switch (channel) {
 439                 case 0:
 440                         /* 1. Set DAC mode */
 441                         rmw[0].address = F020_SFR_DAC0CN;
 442                         rmw[0].and_mask = 0xff;
 443                         rmw[0].or_value = F020_MASK_DACxCN_DACxEN;
 444
 445                         /* 2 load low byte of DAC value first */
 446                         rmw[1].address = F020_SFR_DAC0L;
 447                         rmw[1].and_mask = 0xff;
 448                         rmw[1].or_value = value & 0xff;
 449
 450                         /* 3 load high byte of DAC value next to latch the
 451                            12-bit value */
 452                         rmw[2].address = F020_SFR_DAC0H;
 453                         rmw[2].and_mask = 0xff;
 454                         rmw[2].or_value = (value >> 8) & 0xf;
 455                         break;
 456
 457                 case 1:
 458                         /* 1. Set DAC mode */
 459                         rmw[0].address = F020_SFR_DAC1CN;
 460                         rmw[0].and_mask = 0xff;
 461                         rmw[0].or_value = F020_MASK_DACxCN_DACxEN;
 462
 463                         /* 2 load low byte of DAC value first */
 464                         rmw[1].address = F020_SFR_DAC1L;
 465                         rmw[1].and_mask = 0xff;
 466                         rmw[1].or_value = value & 0xff;
 467
 468                         /* 3 load high byte of DAC value next to latch the
 469                            12-bit value */
 470                         rmw[2].address = F020_SFR_DAC1H;
 471                         rmw[2].and_mask = 0xff;
 472                         rmw[2].or_value = (value >> 8) & 0xf;
 473                         break;
 474                 }
 475                 result = dt9812_rmw_multiple_registers(slot->usb, 3, rmw);
 476                 slot->usb->analog_out_shadow[channel] = value;
 477         }
 478         up(&slot->mutex);
 479
 480         return result;
 481 }
 482
 483 /*
 484  * USB framework functions
 485  */
 486
 487 static int dt9812_probe(struct usb_interface *interface,
 488                         const struct usb_device_id *id)
 489 {
 490         int retval = -ENOMEM;
 491         usb_dt9812_t *dev = NULL;
 492         struct usb_host_interface *iface_desc;
 493         struct usb_endpoint_descriptor *endpoint;
 494         int i;
 495         u8 fw;
 496
 497         /* allocate memory for our device state and initialize it */
 498         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 499         if (dev == NULL) {
 500                 dev_err(&interface->dev, "Out of memory\n");
 501                 goto error;
 502         }
 503         kref_init(&dev->kref);
 504
 505         dev->udev = usb_get_dev(interface_to_usbdev(interface));
 506         dev->interface = interface;
 507
 508         /* Check endpoints */
 509         iface_desc = interface->cur_altsetting;
 510
 511         if (iface_desc->desc.bNumEndpoints != 5) {
 512                 err("Wrong number of endpints.");
 513                 retval = -ENODEV;
 514                 goto error;
 515         }
 516
 517         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 518                 int direction = -1;
 519                 endpoint = &iface_desc->endpoint[i].desc;
 520                 switch (i) {
 521                 case 0:
 522                         direction = USB_DIR_IN;
 523                         dev->message_pipe.addr = endpoint->bEndpointAddress;
 524                         dev->message_pipe.size =
 525                                         le16_to_cpu(endpoint->wMaxPacketSize);
 526
 527                         break;
 528                 case 1:
 529                         direction = USB_DIR_OUT;
 530                         dev->command_write.addr = endpoint->bEndpointAddress;
 531                         dev->command_write.size =
 532                                         le16_to_cpu(endpoint->wMaxPacketSize);
 533                         break;
 534                 case 2:
 535                         direction = USB_DIR_IN;
 536                         dev->command_read.addr = endpoint->bEndpointAddress;
 537                         dev->command_read.size =
 538                                         le16_to_cpu(endpoint->wMaxPacketSize);
 539                         break;
 540                 case 3:
 541                         direction = USB_DIR_OUT;
 542                         dev->write_stream.addr = endpoint->bEndpointAddress;
 543                         dev->write_stream.size =
 544                                         le16_to_cpu(endpoint->wMaxPacketSize);
 545                         break;
 546                 case 4:
 547                         direction = USB_DIR_IN;
 548                         dev->read_stream.addr = endpoint->bEndpointAddress;
 549                         dev->read_stream.size =
 550                                         le16_to_cpu(endpoint->wMaxPacketSize);
 551                         break;
 552                 }
 553                 if ((endpoint->bEndpointAddress & USB_DIR_IN) != direction) {
 554                         dev_err(&interface->dev,
 555                                 "Endpoint has wrong direction.\n");
 556                         retval = -ENODEV;
 557                         goto error;
 558                 }
 559         }
 560         if (dt9812_read_info(dev, 0, &fw, sizeof(fw)) != 0) {
 561                 /*
 562                  * Seems like a configuration reset is necessary if driver is
 563                  * reloaded while device is attached
 564                  */
 565                 int i;
 566
 567                 usb_reset_configuration(dev->udev);
 568                 for (i = 0; i < 10; i++) {
 569                         retval = dt9812_read_info(dev, 1, &fw, sizeof(fw));
 570                         if (retval == 0) {
 571                                 dev_info(&interface->dev,
 572                                          "usb_reset_configuration succeded "
 573                                          "after %d iterations\n", i);
 574                                 break;
 575                         }
 576                 }
 577         }
 578
 579         if (dt9812_read_info(dev, 1, &dev->vendor, sizeof(dev->vendor)) != 0) {
 580                 err("Failed to read vendor.");
 581                 retval = -ENODEV;
 582                 goto error;
 583         }
 584         if (dt9812_read_info(dev, 3, &dev->product,
 585                              sizeof(dev->product)) != 0) {
 586                 err("Failed to read product.");
 587                 retval = -ENODEV;
 588                 goto error;
 589         }
 590         if (dt9812_read_info(dev, 5, &dev->device, sizeof(dev->device)) != 0) {
 591                 err("Failed to read device.");
 592                 retval = -ENODEV;
 593                 goto error;
 594         }
 595         if (dt9812_read_info(dev, 7, &dev->serial, sizeof(dev->serial)) != 0) {
 596                 err("Failed to read serial.");
 597                 retval = -ENODEV;
 598                 goto error;
 599         }
 600
 601         dev->vendor = le16_to_cpu(dev->vendor);
 602         dev->product = le16_to_cpu(dev->product);
 603         dev->device = le16_to_cpu(dev->device);
 604         dev->serial = le32_to_cpu(dev->serial);
 605         switch (dev->device) {
 606         case DT9812_DEVID_DT9812_10:
 607                 dev->analog_out_shadow[0] = 0x0800;
 608                 dev->analog_out_shadow[1] = 0x800;
 609                 break;
 610         case DT9812_DEVID_DT9812_2PT5:
 611                 dev->analog_out_shadow[0] = 0x0000;
 612                 dev->analog_out_shadow[1] = 0x0000;
 613                 break;
 614         }
 615         dev->digital_out_shadow = 0;
 616
 617         /* save our data pointer in this interface device */
 618         usb_set_intfdata(interface, dev);
 619
 620         /* let the user know what node this device is now attached to */
 621         dev_info(&interface->dev, "USB DT9812 (%4.4x.%4.4x.%4.4x) #0x%8.8x\n",
 622                  dev->vendor, dev->product, dev->device, dev->serial);
 623
 624         down(&dt9812_mutex);
 625         {
 626                 /* Find a slot for the USB device */
 627                 slot_dt9812_t *first = NULL;
 628                 slot_dt9812_t *best = NULL;
 629
 630                 for (i = 0; i < DT9812_NUM_SLOTS; i++) {
 631                         if (!first && !dt9812[i].usb && dt9812[i].serial == 0)
 632                                 first = &dt9812[i];
 633                         if (!best && dt9812[i].serial == dev->serial)
 634                                 best = &dt9812[i];
 635                 }
 636
 637                 if (!best)
 638                         best = first;
 639
 640                 if (best) {
 641                         down(&best->mutex);
 642                         best->usb = dev;
 643                         dev->slot = best;
 644                         up(&best->mutex);
 645                 }
 646         }
 647         up(&dt9812_mutex);
 648
 649         return 0;
 650
 651 error:
 652         if (dev)
 653                 kref_put(&dev->kref, dt9812_delete);
 654         return retval;
 655 }
 656
 657 static void dt9812_disconnect(struct usb_interface *interface)
 658 {
 659         usb_dt9812_t *dev;
 660         int minor = interface->minor;
 661
 662         down(&dt9812_mutex);
 663         dev = usb_get_intfdata(interface);
 664         if (dev->slot) {
 665                 down(&dev->slot->mutex);
 666                 dev->slot->usb = NULL;
 667                 up(&dev->slot->mutex);
 668                 dev->slot = NULL;
 669         }
 670         usb_set_intfdata(interface, NULL);
 671         up(&dt9812_mutex);
 672
 673         /* queue final destruction */
 674         kref_put(&dev->kref, dt9812_delete);
 675
 676         dev_info(&interface->dev, "USB Dt9812 #%d now disconnected\n", minor);
 677 }
 678
 679 static struct usb_driver dt9812_usb_driver = {
 680 #ifdef COMEDI_HAVE_USB_DRIVER_OWNER
 681         .owner = THIS_MODULE,
 682 #endif
 683         .name = "dt9812",
 684         .probe = dt9812_probe,
 685         .disconnect = dt9812_disconnect,
 686         .id_table = dt9812_table,
 687 };
 688
 689 /*
 690  * Comedi functions
 691  */
 692
 693 static void dt9812_comedi_open(comedi_device *dev)
 694 {
 695         down(&devpriv->slot->mutex);
 696         if (devpriv->slot->usb) {
 697                 /* We have an attached device, fill in current range info */
 698                 comedi_subdevice *s;
 699
 700                 s = &dev->subdevices[0];
 701                 s->n_chan = 8;
 702                 s->maxdata = 1;
 703
 704                 s = &dev->subdevices[1];
 705                 s->n_chan = 8;
 706                 s->maxdata = 1;
 707
 708                 s = &dev->subdevices[2];
 709                 s->n_chan = 8;
 710                 switch (devpriv->slot->usb->device) {
 711                 case 0:{
 712                                 s->maxdata = 4095;
 713                                 s->range_table = &dt9812_10_ain_range;
 714                         }
 715                         break;
 716                 case 1:{
 717                                 s->maxdata = 4095;
 718                                 s->range_table = &dt9812_2pt5_ain_range;
 719                         }
 720                         break;
 721                 }
 722
 723                 s = &dev->subdevices[3];
 724                 s->n_chan = 2;
 725                 switch (devpriv->slot->usb->device) {
 726                 case 0:{
 727                                 s->maxdata = 4095;
 728                                 s->range_table = &dt9812_10_aout_range;
 729                         }
 730                         break;
 731                 case 1:{
 732                                 s->maxdata = 4095;
 733                                 s->range_table = &dt9812_2pt5_aout_range;
 734                         }
 735                         break;
 736                 }
 737         }
 738         up(&devpriv->slot->mutex);
 739 }
 740
 741 static int dt9812_di_rinsn(comedi_device *dev, comedi_subdevice *s,
 742                            comedi_insn *insn, lsampl_t *data)
 743 {
 744         int n;
 745         u8 bits = 0;
 746
 747         dt9812_digital_in(devpriv->slot, &bits);
 748         for (n = 0; n < insn->n; n++)
 749                 data[n] = ((1 << insn->chanspec) & bits) != 0;
 750         return n;
 751 }
 752
 753 static int dt9812_do_winsn(comedi_device *dev, comedi_subdevice *s,
 754                            comedi_insn *insn, lsampl_t *data)
 755 {
 756         int n;
 757         u8 bits = 0;
 758
 759         dt9812_digital_out_shadow(devpriv->slot, &bits);
 760         for (n = 0; n < insn->n; n++) {
 761                 u8 mask = 1 << insn->chanspec;
 762
 763                 bits &= ~mask;
 764                 if (data[n])
 765                         bits |= mask;
 766         }
 767         dt9812_digital_out(devpriv->slot, bits);
 768         return n;
 769 }
 770
 771 static int dt9812_ai_rinsn(comedi_device *dev, comedi_subdevice *s,
 772                            comedi_insn *insn, lsampl_t *data)
 773 {
 774         int n;
 775
 776         for (n = 0; n < insn->n; n++) {
 777                 u16 value = 0;
 778
 779                 dt9812_analog_in(devpriv->slot, insn->chanspec, &value,
 780                                  DT9812_GAIN_1);
 781                 data[n] = value;
 782         }
 783         return n;
 784 }
 785
 786 static int dt9812_ao_rinsn(comedi_device *dev, comedi_subdevice *s,
 787                            comedi_insn *insn, lsampl_t *data)
 788 {
 789         int n;
 790         u16 value;
 791
 792         for (n = 0; n < insn->n; n++) {
 793                 value = 0;
 794                 dt9812_analog_out_shadow(devpriv->slot, insn->chanspec, &value);
 795                 data[n] = value;
 796         }
 797         return n;
 798 }
 799
 800 static int dt9812_ao_winsn(comedi_device *dev, comedi_subdevice *s,
 801                            comedi_insn *insn, lsampl_t *data)
 802 {
 803         int n;
 804
 805         for (n = 0; n < insn->n; n++)
 806                 dt9812_analog_out(devpriv->slot, insn->chanspec, data[n]);
 807         return n;
 808 }
 809
 810 static int dt9812_attach(comedi_device *dev, comedi_devconfig *it)
 811 {
 812         int i;
 813         comedi_subdevice *s;
 814
 815         dev->board_name = "dt9812";
 816
 817         if (alloc_private(dev, sizeof(comedi_dt9812_t)) < 0)
 818                 return -ENOMEM;
 819
 820         /*
 821          * Special open routine, since USB unit may be unattached at
 822          * comedi_config time, hence range can not be determined
 823          */
 824         dev->open = dt9812_comedi_open;
 825
 826         devpriv->serial = it->options[0];
 827
 828         /* Allocate subdevices */
 829         if (alloc_subdevices(dev, 4) < 0)
 830                 return -ENOMEM;
 831
 832         /* digital input subdevice */
 833         s = dev->subdevices + 0;
 834         s->type = COMEDI_SUBD_DI;
 835         s->subdev_flags = SDF_READABLE;
 836         s->n_chan = 0;
 837         s->maxdata = 1;
 838         s->range_table = &range_digital;
 839         s->insn_read = &dt9812_di_rinsn;
 840
 841         /* digital output subdevice */
 842         s = dev->subdevices + 1;
 843         s->type = COMEDI_SUBD_DO;
 844         s->subdev_flags = SDF_WRITEABLE;
 845         s->n_chan = 0;
 846         s->maxdata = 1;
 847         s->range_table = &range_digital;
 848         s->insn_write = &dt9812_do_winsn;
 849
 850         /* analog input subdevice */
 851         s = dev->subdevices + 2;
 852         s->type = COMEDI_SUBD_AI;
 853         s->subdev_flags = SDF_READABLE | SDF_GROUND;
 854         s->n_chan = 0;
 855         s->maxdata = 1;
 856         s->range_table = 0;
 857         s->insn_read = &dt9812_ai_rinsn;
 858
 859         /* analog output subdevice */
 860         s = dev->subdevices + 3;
 861         s->type = COMEDI_SUBD_AO;
 862         s->subdev_flags = SDF_WRITEABLE;
 863         s->n_chan = 0;
 864         s->maxdata = 1;
 865         s->range_table = 0;
 866         s->insn_write = &dt9812_ao_winsn;
 867         s->insn_read = &dt9812_ao_rinsn;
 868
 869         printk(KERN_INFO "comedi%d: successfully attached to dt9812.\n",
 870                dev->minor);
 871
 872         down(&dt9812_mutex);
 873         /* Find a slot for the comedi device */
 874         {
 875                 slot_dt9812_t *first = NULL;
 876                 slot_dt9812_t *best = NULL;
 877                 for (i = 0; i < DT9812_NUM_SLOTS; i++) {
 878                         if (!first && !dt9812[i].comedi) {
 879                                 /* First free slot from comedi side */
 880                                 first = &dt9812[i];
 881                         }
 882                         if (!best &&
 883                             dt9812[i].usb &&
 884                             dt9812[i].usb->serial == devpriv->serial) {
 885                                 /* We have an attaced device with matching ID */
 886                                 best = &dt9812[i];
 887                         }
 888                 }
 889                 if (!best)
 890                         best = first;
 891                 if (best) {
 892                         down(&best->mutex);
 893                         best->comedi = devpriv;
 894                         best->serial = devpriv->serial;
 895                         devpriv->slot = best;
 896                         up(&best->mutex);
 897                 }
 898         }
 899         up(&dt9812_mutex);
 900
 901         return 0;
 902 }
 903
 904 static int dt9812_detach(comedi_device *dev)
 905 {
 906         return 0;
 907 }
 908
 909 static comedi_driver dt9812_comedi_driver = {
 910         .module = THIS_MODULE,
 911         .driver_name = "dt9812",
 912         .attach = dt9812_attach,
 913         .detach = dt9812_detach,
 914 };
 915
 916 static int __init usb_dt9812_init(void)
 917 {
 918         int result, i;
 919
 920         /* Initialize all driver slots */
 921         for (i = 0; i < DT9812_NUM_SLOTS; i++) {
 922                 init_MUTEX(&dt9812[i].mutex);
 923                 dt9812[i].serial = 0;
 924                 dt9812[i].usb = NULL;
 925                 dt9812[i].comedi = NULL;
 926         }
 927         dt9812[12].serial = 0x0;
 928
 929         /* register with the USB subsystem */
 930         result = usb_register(&dt9812_usb_driver);
 931         if (result) {
 932                 printk(KERN_ERR KBUILD_MODNAME
 933                        ": usb_register failed. Error number %d\n", result);
 934                 return result;
 935         }
 936         /* register with comedi */
 937         result = comedi_driver_register(&dt9812_comedi_driver);
 938         if (result) {
 939                 usb_deregister(&dt9812_usb_driver);
 940                 err("comedi_driver_register failed. Error number %d", result);
 941         }
 942
 943         return result;
 944 }
 945
 946 static void __exit usb_dt9812_exit(void)
 947 {
 948         /* unregister with comedi */
 949         comedi_driver_unregister(&dt9812_comedi_driver);
 950
 951         /* deregister this driver with the USB subsystem */
 952         usb_deregister(&dt9812_usb_driver);
 953 }
 954
 955 module_init(usb_dt9812_init);
 956 module_exit(usb_dt9812_exit);
 957
 958 MODULE_AUTHOR("Anders Blomdell <anders.blomdell@control.lth.se>");
 959 MODULE_DESCRIPTION("Comedi DT9812 driver");
 960 MODULE_LICENSE("GPL");