1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * Comedi driver for CIO-DAS16/M1 4 * Author: Frank Mori Hess, based on code from the das16 driver. 5 * Copyright (C) 2001 Frank Mori Hess <fmhess@users.sourceforge.net> 6 * 7 * COMEDI - Linux Control and Measurement Device Interface 8 * Copyright (C) 2000 David A. Schleef <ds@schleef.org> 9 */ 10 11/* 12 * Driver: das16m1 13 * Description: CIO-DAS16/M1 14 * Author: Frank Mori Hess <fmhess@users.sourceforge.net> 15 * Devices: [Measurement Computing] CIO-DAS16/M1 (das16m1) 16 * Status: works 17 * 18 * This driver supports a single board - the CIO-DAS16/M1. As far as I know, 19 * there are no other boards that have the same register layout. Even the 20 * CIO-DAS16/M1/16 is significantly different. 21 * 22 * I was _barely_ able to reach the full 1 MHz capability of this board, using 23 * a hard real-time interrupt (set the TRIG_RT flag in your struct comedi_cmd 24 * and use rtlinux or RTAI). The board can't do dma, so the bottleneck is 25 * pulling the data across the ISA bus. I timed the interrupt handler, and it 26 * took my computer ~470 microseconds to pull 512 samples from the board. So 27 * at 1 Mhz sampling rate, expect your CPU to be spending almost all of its 28 * time in the interrupt handler. 29 * 30 * This board has some unusual restrictions for its channel/gain list. If the 31 * list has 2 or more channels in it, then two conditions must be satisfied: 32 * (1) - even/odd channels must appear at even/odd indices in the list 33 * (2) - the list must have an even number of entries. 34 * 35 * Configuration options: 36 * [0] - base io address 37 * [1] - irq (optional, but you probably want it) 38 * 39 * irq can be omitted, although the cmd interface will not work without it. 40 */ 41 42#include <linux/module.h> 43#include <linux/slab.h> 44#include <linux/interrupt.h> 45#include <linux/comedi/comedidev.h> 46#include <linux/comedi/comedi_8255.h> 47#include <linux/comedi/comedi_8254.h> 48 49/* 50 * Register map (dev->iobase) 51 */ 52#define DAS16M1_AI_REG 0x00 /* 16-bit register */ 53#define DAS16M1_AI_TO_CHAN(x) (((x) >> 0) & 0xf) 54#define DAS16M1_AI_TO_SAMPLE(x) (((x) >> 4) & 0xfff) 55#define DAS16M1_CS_REG 0x02 56#define DAS16M1_CS_EXT_TRIG BIT(0) 57#define DAS16M1_CS_OVRUN BIT(5) 58#define DAS16M1_CS_IRQDATA BIT(7) 59#define DAS16M1_DI_REG 0x03 60#define DAS16M1_DO_REG 0x03 61#define DAS16M1_CLR_INTR_REG 0x04 62#define DAS16M1_INTR_CTRL_REG 0x05 63#define DAS16M1_INTR_CTRL_PACER(x) (((x) & 0x3) << 0) 64#define DAS16M1_INTR_CTRL_PACER_EXT DAS16M1_INTR_CTRL_PACER(2) 65#define DAS16M1_INTR_CTRL_PACER_INT DAS16M1_INTR_CTRL_PACER(3) 66#define DAS16M1_INTR_CTRL_PACER_MASK DAS16M1_INTR_CTRL_PACER(3) 67#define DAS16M1_INTR_CTRL_IRQ(x) (((x) & 0x7) << 4) 68#define DAS16M1_INTR_CTRL_INTE BIT(7) 69#define DAS16M1_Q_ADDR_REG 0x06 70#define DAS16M1_Q_REG 0x07 71#define DAS16M1_Q_CHAN(x) (((x) & 0x7) << 0) 72#define DAS16M1_Q_RANGE(x) (((x) & 0xf) << 4) 73#define DAS16M1_8254_IOBASE1 0x08 74#define DAS16M1_8254_IOBASE2 0x0c 75#define DAS16M1_8255_IOBASE 0x400 76#define DAS16M1_8254_IOBASE3 0x404 77 78#define DAS16M1_SIZE2 0x08 79 80#define DAS16M1_AI_FIFO_SZ 1024 /* # samples */ 81 82static const struct comedi_lrange range_das16m1 = { 83 9, { 84 BIP_RANGE(5), 85 BIP_RANGE(2.5), 86 BIP_RANGE(1.25), 87 BIP_RANGE(0.625), 88 UNI_RANGE(10), 89 UNI_RANGE(5), 90 UNI_RANGE(2.5), 91 UNI_RANGE(1.25), 92 BIP_RANGE(10) 93 } 94}; 95 96struct das16m1_private { 97 struct comedi_8254 *counter; 98 unsigned int intr_ctrl; 99 unsigned int adc_count; 100 u16 initial_hw_count; 101 unsigned short ai_buffer[DAS16M1_AI_FIFO_SZ]; 102 unsigned long extra_iobase; 103}; 104 105static void das16m1_ai_set_queue(struct comedi_device *dev, 106 unsigned int *chanspec, unsigned int len) 107{ 108 unsigned int i; 109 110 for (i = 0; i < len; i++) { 111 unsigned int chan = CR_CHAN(chanspec[i]); 112 unsigned int range = CR_RANGE(chanspec[i]); 113 114 outb(i, dev->iobase + DAS16M1_Q_ADDR_REG); 115 outb(DAS16M1_Q_CHAN(chan) | DAS16M1_Q_RANGE(range), 116 dev->iobase + DAS16M1_Q_REG); 117 } 118} 119 120static void das16m1_ai_munge(struct comedi_device *dev, 121 struct comedi_subdevice *s, 122 void *data, unsigned int num_bytes, 123 unsigned int start_chan_index) 124{ 125 unsigned short *array = data; 126 unsigned int nsamples = comedi_bytes_to_samples(s, num_bytes); 127 unsigned int i; 128 129 /* 130 * The fifo values have the channel number in the lower 4-bits and 131 * the sample in the upper 12-bits. This just shifts the values 132 * to remove the channel numbers. 133 */ 134 for (i = 0; i < nsamples; i++) 135 array[i] = DAS16M1_AI_TO_SAMPLE(array[i]); 136} 137 138static int das16m1_ai_check_chanlist(struct comedi_device *dev, 139 struct comedi_subdevice *s, 140 struct comedi_cmd *cmd) 141{ 142 int i; 143 144 if (cmd->chanlist_len == 1) 145 return 0; 146 147 if ((cmd->chanlist_len % 2) != 0) { 148 dev_dbg(dev->class_dev, 149 "chanlist must be of even length or length 1\n"); 150 return -EINVAL; 151 } 152 153 for (i = 0; i < cmd->chanlist_len; i++) { 154 unsigned int chan = CR_CHAN(cmd->chanlist[i]); 155 156 if ((i % 2) != (chan % 2)) { 157 dev_dbg(dev->class_dev, 158 "even/odd channels must go have even/odd chanlist indices\n"); 159 return -EINVAL; 160 } 161 } 162 163 return 0; 164} 165 166static int das16m1_ai_cmdtest(struct comedi_device *dev, 167 struct comedi_subdevice *s, 168 struct comedi_cmd *cmd) 169{ 170 int err = 0; 171 172 /* Step 1 : check if triggers are trivially valid */ 173 174 err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_EXT); 175 err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_FOLLOW); 176 err |= comedi_check_trigger_src(&cmd->convert_src, 177 TRIG_TIMER | TRIG_EXT); 178 err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT); 179 err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE); 180 181 if (err) 182 return 1; 183 184 /* Step 2a : make sure trigger sources are unique */ 185 186 err |= comedi_check_trigger_is_unique(cmd->start_src); 187 err |= comedi_check_trigger_is_unique(cmd->convert_src); 188 err |= comedi_check_trigger_is_unique(cmd->stop_src); 189 190 /* Step 2b : and mutually compatible */ 191 192 if (err) 193 return 2; 194 195 /* Step 3: check if arguments are trivially valid */ 196 197 err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0); 198 199 if (cmd->scan_begin_src == TRIG_FOLLOW) /* internal trigger */ 200 err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, 0); 201 202 if (cmd->convert_src == TRIG_TIMER) 203 err |= comedi_check_trigger_arg_min(&cmd->convert_arg, 1000); 204 205 err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg, 206 cmd->chanlist_len); 207 208 if (cmd->stop_src == TRIG_COUNT) 209 err |= comedi_check_trigger_arg_min(&cmd->stop_arg, 1); 210 else /* TRIG_NONE */ 211 err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0); 212 213 if (err) 214 return 3; 215 216 /* step 4: fix up arguments */ 217 218 if (cmd->convert_src == TRIG_TIMER) { 219 unsigned int arg = cmd->convert_arg; 220 221 comedi_8254_cascade_ns_to_timer(dev->pacer, &arg, cmd->flags); 222 err |= comedi_check_trigger_arg_is(&cmd->convert_arg, arg); 223 } 224 225 if (err) 226 return 4; 227 228 /* Step 5: check channel list if it exists */ 229 if (cmd->chanlist && cmd->chanlist_len > 0) 230 err |= das16m1_ai_check_chanlist(dev, s, cmd); 231 232 if (err) 233 return 5; 234 235 return 0; 236} 237 238static int das16m1_ai_cmd(struct comedi_device *dev, 239 struct comedi_subdevice *s) 240{ 241 struct das16m1_private *devpriv = dev->private; 242 struct comedi_async *async = s->async; 243 struct comedi_cmd *cmd = &async->cmd; 244 unsigned int byte; 245 246 /* set software count */ 247 devpriv->adc_count = 0; 248 249 /* 250 * Initialize lower half of hardware counter, used to determine how 251 * many samples are in fifo. Value doesn't actually load into counter 252 * until counter's next clock (the next a/d conversion). 253 */ 254 comedi_8254_set_mode(devpriv->counter, 1, I8254_MODE2 | I8254_BINARY); 255 comedi_8254_write(devpriv->counter, 1, 0); 256 257 /* 258 * Remember current reading of counter so we know when counter has 259 * actually been loaded. 260 */ 261 devpriv->initial_hw_count = comedi_8254_read(devpriv->counter, 1); 262 263 das16m1_ai_set_queue(dev, cmd->chanlist, cmd->chanlist_len); 264 265 /* enable interrupts and set internal pacer counter mode and counts */ 266 devpriv->intr_ctrl &= ~DAS16M1_INTR_CTRL_PACER_MASK; 267 if (cmd->convert_src == TRIG_TIMER) { 268 comedi_8254_update_divisors(dev->pacer); 269 comedi_8254_pacer_enable(dev->pacer, 1, 2, true); 270 devpriv->intr_ctrl |= DAS16M1_INTR_CTRL_PACER_INT; 271 } else { /* TRIG_EXT */ 272 devpriv->intr_ctrl |= DAS16M1_INTR_CTRL_PACER_EXT; 273 } 274 275 /* set control & status register */ 276 byte = 0; 277 /* 278 * If we are using external start trigger (also board dislikes having 279 * both start and conversion triggers external simultaneously). 280 */ 281 if (cmd->start_src == TRIG_EXT && cmd->convert_src != TRIG_EXT) 282 byte |= DAS16M1_CS_EXT_TRIG; 283 284 outb(byte, dev->iobase + DAS16M1_CS_REG); 285 286 /* clear interrupt */ 287 outb(0, dev->iobase + DAS16M1_CLR_INTR_REG); 288 289 devpriv->intr_ctrl |= DAS16M1_INTR_CTRL_INTE; 290 outb(devpriv->intr_ctrl, dev->iobase + DAS16M1_INTR_CTRL_REG); 291 292 return 0; 293} 294 295static int das16m1_ai_cancel(struct comedi_device *dev, 296 struct comedi_subdevice *s) 297{ 298 struct das16m1_private *devpriv = dev->private; 299 300 /* disable interrupts and pacer */ 301 devpriv->intr_ctrl &= ~(DAS16M1_INTR_CTRL_INTE | 302 DAS16M1_INTR_CTRL_PACER_MASK); 303 outb(devpriv->intr_ctrl, dev->iobase + DAS16M1_INTR_CTRL_REG); 304 305 return 0; 306} 307 308static int das16m1_ai_eoc(struct comedi_device *dev, 309 struct comedi_subdevice *s, 310 struct comedi_insn *insn, 311 unsigned long context) 312{ 313 unsigned int status; 314 315 status = inb(dev->iobase + DAS16M1_CS_REG); 316 if (status & DAS16M1_CS_IRQDATA) 317 return 0; 318 return -EBUSY; 319} 320 321static int das16m1_ai_insn_read(struct comedi_device *dev, 322 struct comedi_subdevice *s, 323 struct comedi_insn *insn, 324 unsigned int *data) 325{ 326 int ret; 327 int i; 328 329 das16m1_ai_set_queue(dev, &insn->chanspec, 1); 330 331 for (i = 0; i < insn->n; i++) { 332 unsigned short val; 333 334 /* clear interrupt */ 335 outb(0, dev->iobase + DAS16M1_CLR_INTR_REG); 336 /* trigger conversion */ 337 outb(0, dev->iobase + DAS16M1_AI_REG); 338 339 ret = comedi_timeout(dev, s, insn, das16m1_ai_eoc, 0); 340 if (ret) 341 return ret; 342 343 val = inw(dev->iobase + DAS16M1_AI_REG); 344 data[i] = DAS16M1_AI_TO_SAMPLE(val); 345 } 346 347 return insn->n; 348} 349 350static int das16m1_di_insn_bits(struct comedi_device *dev, 351 struct comedi_subdevice *s, 352 struct comedi_insn *insn, 353 unsigned int *data) 354{ 355 data[1] = inb(dev->iobase + DAS16M1_DI_REG) & 0xf; 356 357 return insn->n; 358} 359 360static int das16m1_do_insn_bits(struct comedi_device *dev, 361 struct comedi_subdevice *s, 362 struct comedi_insn *insn, 363 unsigned int *data) 364{ 365 if (comedi_dio_update_state(s, data)) 366 outb(s->state, dev->iobase + DAS16M1_DO_REG); 367 368 data[1] = s->state; 369 370 return insn->n; 371} 372 373static void das16m1_handler(struct comedi_device *dev, unsigned int status) 374{ 375 struct das16m1_private *devpriv = dev->private; 376 struct comedi_subdevice *s = dev->read_subdev; 377 struct comedi_async *async = s->async; 378 struct comedi_cmd *cmd = &async->cmd; 379 u16 num_samples; 380 u16 hw_counter; 381 382 /* figure out how many samples are in fifo */ 383 hw_counter = comedi_8254_read(devpriv->counter, 1); 384 /* 385 * Make sure hardware counter reading is not bogus due to initial 386 * value not having been loaded yet. 387 */ 388 if (devpriv->adc_count == 0 && 389 hw_counter == devpriv->initial_hw_count) { 390 num_samples = 0; 391 } else { 392 /* 393 * The calculation of num_samples looks odd, but it uses the 394 * following facts. 16 bit hardware counter is initialized with 395 * value of zero (which really means 0x1000). The counter 396 * decrements by one on each conversion (when the counter 397 * decrements from zero it goes to 0xffff). num_samples is a 398 * 16 bit variable, so it will roll over in a similar fashion 399 * to the hardware counter. Work it out, and this is what you 400 * get. 401 */ 402 num_samples = -hw_counter - devpriv->adc_count; 403 } 404 /* check if we only need some of the points */ 405 if (cmd->stop_src == TRIG_COUNT) { 406 if (num_samples > cmd->stop_arg * cmd->chanlist_len) 407 num_samples = cmd->stop_arg * cmd->chanlist_len; 408 } 409 /* make sure we don't try to get too many points if fifo has overrun */ 410 if (num_samples > DAS16M1_AI_FIFO_SZ) 411 num_samples = DAS16M1_AI_FIFO_SZ; 412 insw(dev->iobase, devpriv->ai_buffer, num_samples); 413 comedi_buf_write_samples(s, devpriv->ai_buffer, num_samples); 414 devpriv->adc_count += num_samples; 415 416 if (cmd->stop_src == TRIG_COUNT) { 417 if (devpriv->adc_count >= cmd->stop_arg * cmd->chanlist_len) { 418 /* end of acquisition */ 419 async->events |= COMEDI_CB_EOA; 420 } 421 } 422 423 /* 424 * This probably won't catch overruns since the card doesn't generate 425 * overrun interrupts, but we might as well try. 426 */ 427 if (status & DAS16M1_CS_OVRUN) { 428 async->events |= COMEDI_CB_ERROR; 429 dev_err(dev->class_dev, "fifo overflow\n"); 430 } 431 432 comedi_handle_events(dev, s); 433} 434 435static int das16m1_ai_poll(struct comedi_device *dev, 436 struct comedi_subdevice *s) 437{ 438 unsigned long flags; 439 unsigned int status; 440 441 /* prevent race with interrupt handler */ 442 spin_lock_irqsave(&dev->spinlock, flags); 443 status = inb(dev->iobase + DAS16M1_CS_REG); 444 das16m1_handler(dev, status); 445 spin_unlock_irqrestore(&dev->spinlock, flags); 446 447 return comedi_buf_n_bytes_ready(s); 448} 449 450static irqreturn_t das16m1_interrupt(int irq, void *d) 451{ 452 int status; 453 struct comedi_device *dev = d; 454 455 if (!dev->attached) { 456 dev_err(dev->class_dev, "premature interrupt\n"); 457 return IRQ_HANDLED; 458 } 459 /* prevent race with comedi_poll() */ 460 spin_lock(&dev->spinlock); 461 462 status = inb(dev->iobase + DAS16M1_CS_REG); 463 464 if ((status & (DAS16M1_CS_IRQDATA | DAS16M1_CS_OVRUN)) == 0) { 465 dev_err(dev->class_dev, "spurious interrupt\n"); 466 spin_unlock(&dev->spinlock); 467 return IRQ_NONE; 468 } 469 470 das16m1_handler(dev, status); 471 472 /* clear interrupt */ 473 outb(0, dev->iobase + DAS16M1_CLR_INTR_REG); 474 475 spin_unlock(&dev->spinlock); 476 return IRQ_HANDLED; 477} 478 479static int das16m1_irq_bits(unsigned int irq) 480{ 481 switch (irq) { 482 case 10: 483 return 0x0; 484 case 11: 485 return 0x1; 486 case 12: 487 return 0x2; 488 case 15: 489 return 0x3; 490 case 2: 491 return 0x4; 492 case 3: 493 return 0x5; 494 case 5: 495 return 0x6; 496 case 7: 497 return 0x7; 498 default: 499 return 0x0; 500 } 501} 502 503static int das16m1_attach(struct comedi_device *dev, 504 struct comedi_devconfig *it) 505{ 506 struct das16m1_private *devpriv; 507 struct comedi_subdevice *s; 508 int ret; 509 510 devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv)); 511 if (!devpriv) 512 return -ENOMEM; 513 514 ret = comedi_request_region(dev, it->options[0], 0x10); 515 if (ret) 516 return ret; 517 /* Request an additional region for the 8255 and 3rd 8254 */ 518 ret = __comedi_request_region(dev, dev->iobase + DAS16M1_8255_IOBASE, 519 DAS16M1_SIZE2); 520 if (ret) 521 return ret; 522 devpriv->extra_iobase = dev->iobase + DAS16M1_8255_IOBASE; 523 524 /* only irqs 2, 3, 4, 5, 6, 7, 10, 11, 12, 14, and 15 are valid */ 525 if ((1 << it->options[1]) & 0xdcfc) { 526 ret = request_irq(it->options[1], das16m1_interrupt, 0, 527 dev->board_name, dev); 528 if (ret == 0) 529 dev->irq = it->options[1]; 530 } 531 532 dev->pacer = comedi_8254_io_alloc(dev->iobase + DAS16M1_8254_IOBASE2, 533 I8254_OSC_BASE_10MHZ, I8254_IO8, 0); 534 if (IS_ERR(dev->pacer)) 535 return PTR_ERR(dev->pacer); 536 537 devpriv->counter = 538 comedi_8254_io_alloc(dev->iobase + DAS16M1_8254_IOBASE1, 539 0, I8254_IO8, 0); 540 if (IS_ERR(devpriv->counter)) 541 return PTR_ERR(devpriv->counter); 542 543 ret = comedi_alloc_subdevices(dev, 4); 544 if (ret) 545 return ret; 546 547 /* Analog Input subdevice */ 548 s = &dev->subdevices[0]; 549 s->type = COMEDI_SUBD_AI; 550 s->subdev_flags = SDF_READABLE | SDF_DIFF; 551 s->n_chan = 8; 552 s->maxdata = 0x0fff; 553 s->range_table = &range_das16m1; 554 s->insn_read = das16m1_ai_insn_read; 555 if (dev->irq) { 556 dev->read_subdev = s; 557 s->subdev_flags |= SDF_CMD_READ; 558 s->len_chanlist = 256; 559 s->do_cmdtest = das16m1_ai_cmdtest; 560 s->do_cmd = das16m1_ai_cmd; 561 s->cancel = das16m1_ai_cancel; 562 s->poll = das16m1_ai_poll; 563 s->munge = das16m1_ai_munge; 564 } 565 566 /* Digital Input subdevice */ 567 s = &dev->subdevices[1]; 568 s->type = COMEDI_SUBD_DI; 569 s->subdev_flags = SDF_READABLE; 570 s->n_chan = 4; 571 s->maxdata = 1; 572 s->range_table = &range_digital; 573 s->insn_bits = das16m1_di_insn_bits; 574 575 /* Digital Output subdevice */ 576 s = &dev->subdevices[2]; 577 s->type = COMEDI_SUBD_DO; 578 s->subdev_flags = SDF_WRITABLE; 579 s->n_chan = 4; 580 s->maxdata = 1; 581 s->range_table = &range_digital; 582 s->insn_bits = das16m1_do_insn_bits; 583 584 /* Digital I/O subdevice (8255) */ 585 s = &dev->subdevices[3]; 586 ret = subdev_8255_io_init(dev, s, DAS16M1_8255_IOBASE); 587 if (ret) 588 return ret; 589 590 /* initialize digital output lines */ 591 outb(0, dev->iobase + DAS16M1_DO_REG); 592 593 /* set the interrupt level */ 594 devpriv->intr_ctrl = DAS16M1_INTR_CTRL_IRQ(das16m1_irq_bits(dev->irq)); 595 outb(devpriv->intr_ctrl, dev->iobase + DAS16M1_INTR_CTRL_REG); 596 597 return 0; 598} 599 600static void das16m1_detach(struct comedi_device *dev) 601{ 602 struct das16m1_private *devpriv = dev->private; 603 604 if (devpriv) { 605 if (devpriv->extra_iobase) 606 release_region(devpriv->extra_iobase, DAS16M1_SIZE2); 607 if (!IS_ERR(devpriv->counter)) 608 kfree(devpriv->counter); 609 } 610 comedi_legacy_detach(dev); 611} 612 613static struct comedi_driver das16m1_driver = { 614 .driver_name = "das16m1", 615 .module = THIS_MODULE, 616 .attach = das16m1_attach, 617 .detach = das16m1_detach, 618}; 619module_comedi_driver(das16m1_driver); 620 621MODULE_AUTHOR("Comedi https://www.comedi.org"); 622MODULE_DESCRIPTION("Comedi driver for CIO-DAS16/M1 ISA cards"); 623MODULE_LICENSE("GPL"); 624