1 // SPDX-License-Identifier: GPL-2.0+
3 * Comedi driver for National Instruments AT-A2150 boards
4 * Copyright (C) 2001, 2002 Frank Mori Hess <fmhess@users.sourceforge.net>
6 * COMEDI - Linux Control and Measurement Device Interface
7 * Copyright (C) 2000 David A. Schleef <ds@schleef.org>
12 * Description: National Instruments AT-A2150
13 * Author: Frank Mori Hess
15 * Devices: [National Instruments] AT-A2150C (at_a2150c), AT-2150S (at_a2150s)
17 * Configuration options:
18 * [0] - I/O port base address
19 * [1] - IRQ (optional, required for timed conversions)
20 * [2] - DMA (optional, required for timed conversions)
22 * Yet another driver for obsolete hardware brought to you by Frank Hess.
23 * Testing and debugging help provided by Dave Andruczyk.
25 * If you want to ac couple the board's inputs, use AREF_OTHER.
27 * The only difference in the boards is their master clock frequencies.
29 * References (from ftp://ftp.natinst.com/support/manuals):
30 * 320360.pdf AT-A2150 User Manual
33 * - analog level triggering
37 #include <linux/module.h>
38 #include <linux/delay.h>
39 #include <linux/interrupt.h>
40 #include <linux/slab.h>
42 #include <linux/comedi/comedidev.h>
43 #include <linux/comedi/comedi_8254.h>
44 #include <linux/comedi/comedi_isadma.h>
46 #define A2150_DMA_BUFFER_SIZE 0xff00 /* size in bytes of dma buffer */
48 /* Registers and bits */
49 #define CONFIG_REG 0x0
50 #define CHANNEL_BITS(x) ((x) & 0x7)
51 #define CHANNEL_MASK 0x7
52 #define CLOCK_SELECT_BITS(x) (((x) & 0x3) << 3)
53 #define CLOCK_DIVISOR_BITS(x) (((x) & 0x3) << 5)
54 #define CLOCK_MASK (0xf << 3)
55 /* enable (don't internally ground) channels 0 and 1 */
56 #define ENABLE0_BIT 0x80
57 /* enable (don't internally ground) channels 2 and 3 */
58 #define ENABLE1_BIT 0x100
59 #define AC0_BIT 0x200 /* ac couple channels 0,1 */
60 #define AC1_BIT 0x400 /* ac couple channels 2,3 */
61 #define APD_BIT 0x800 /* analog power down */
62 #define DPD_BIT 0x1000 /* digital power down */
63 #define TRIGGER_REG 0x2 /* trigger config register */
64 #define POST_TRIGGER_BITS 0x2
65 #define DELAY_TRIGGER_BITS 0x3
66 #define HW_TRIG_EN 0x10 /* enable hardware trigger */
67 #define FIFO_START_REG 0x6 /* software start aquistion trigger */
68 #define FIFO_RESET_REG 0x8 /* clears fifo + fifo flags */
69 #define FIFO_DATA_REG 0xa /* read data */
70 #define DMA_TC_CLEAR_REG 0xe /* clear dma terminal count interrupt */
71 #define STATUS_REG 0x12 /* read only */
72 #define FNE_BIT 0x1 /* fifo not empty */
73 #define OVFL_BIT 0x8 /* fifo overflow */
74 #define EDAQ_BIT 0x10 /* end of acquisition interrupt */
75 #define DCAL_BIT 0x20 /* offset calibration in progress */
76 #define INTR_BIT 0x40 /* interrupt has occurred */
77 /* dma terminal count interrupt has occurred */
78 #define DMA_TC_BIT 0x80
79 #define ID_BITS(x) (((x) >> 8) & 0x3)
80 #define IRQ_DMA_CNTRL_REG 0x12 /* write only */
81 #define DMA_CHAN_BITS(x) ((x) & 0x7) /* sets dma channel */
82 #define DMA_EN_BIT 0x8 /* enables dma */
83 #define IRQ_LVL_BITS(x) (((x) & 0xf) << 4) /* sets irq level */
84 #define FIFO_INTR_EN_BIT 0x100 /* enable fifo interrupts */
85 #define FIFO_INTR_FHF_BIT 0x200 /* interrupt fifo half full */
86 /* enable interrupt on dma terminal count */
87 #define DMA_INTR_EN_BIT 0x800
88 #define DMA_DEM_EN_BIT 0x1000 /* enables demand mode dma */
89 #define I8253_BASE_REG 0x14
93 int clock[4]; /* master clock periods, in nanoseconds */
94 int num_clocks; /* number of available master clock speeds */
95 int ai_speed; /* maximum conversion rate in nanoseconds */
98 /* analog input range */
99 static const struct comedi_lrange range_a2150 = {
105 /* enum must match board indices */
106 enum { a2150_c, a2150_s };
107 static const struct a2150_board a2150_boards[] = {
110 .clock = {31250, 22676, 20833, 19531},
116 .clock = {62500, 50000, 41667, 0},
122 struct a2150_private {
123 struct comedi_isadma *dma;
124 unsigned int count; /* number of data points left to be taken */
125 int irq_dma_bits; /* irq/dma register bits */
126 int config_bits; /* config register bits */
129 /* interrupt service routine */
130 static irqreturn_t a2150_interrupt(int irq, void *d)
132 struct comedi_device *dev = d;
133 struct a2150_private *devpriv = dev->private;
134 struct comedi_isadma *dma = devpriv->dma;
135 struct comedi_isadma_desc *desc = &dma->desc[0];
136 struct comedi_subdevice *s = dev->read_subdev;
137 struct comedi_async *async = s->async;
138 struct comedi_cmd *cmd = &async->cmd;
139 unsigned short *buf = desc->virt_addr;
140 unsigned int max_points, num_points, residue, leftover;
148 status = inw(dev->iobase + STATUS_REG);
149 if ((status & INTR_BIT) == 0)
152 if (status & OVFL_BIT) {
153 async->events |= COMEDI_CB_ERROR;
154 comedi_handle_events(dev, s);
157 if ((status & DMA_TC_BIT) == 0) {
158 async->events |= COMEDI_CB_ERROR;
159 comedi_handle_events(dev, s);
164 * residue is the number of bytes left to be done on the dma
165 * transfer. It should always be zero at this point unless
166 * the stop_src is set to external triggering.
168 residue = comedi_isadma_disable(desc->chan);
170 /* figure out how many points to read */
171 max_points = comedi_bytes_to_samples(s, desc->size);
172 num_points = max_points - comedi_bytes_to_samples(s, residue);
173 if (devpriv->count < num_points && cmd->stop_src == TRIG_COUNT)
174 num_points = devpriv->count;
176 /* figure out how many points will be stored next time */
178 if (cmd->stop_src == TRIG_NONE) {
179 leftover = comedi_bytes_to_samples(s, desc->size);
180 } else if (devpriv->count > max_points) {
181 leftover = devpriv->count - max_points;
182 if (leftover > max_points)
183 leftover = max_points;
186 * There should only be a residue if collection was stopped by having
187 * the stop_src set to an external trigger, in which case there
188 * will be no more data
193 for (i = 0; i < num_points; i++) {
194 /* write data point to comedi buffer */
196 /* convert from 2's complement to unsigned coding */
198 comedi_buf_write_samples(s, &dpnt, 1);
199 if (cmd->stop_src == TRIG_COUNT) {
200 if (--devpriv->count == 0) { /* end of acquisition */
201 async->events |= COMEDI_CB_EOA;
208 desc->size = comedi_samples_to_bytes(s, leftover);
209 comedi_isadma_program(desc);
212 comedi_handle_events(dev, s);
214 /* clear interrupt */
215 outw(0x00, dev->iobase + DMA_TC_CLEAR_REG);
220 static int a2150_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
222 struct a2150_private *devpriv = dev->private;
223 struct comedi_isadma *dma = devpriv->dma;
224 struct comedi_isadma_desc *desc = &dma->desc[0];
226 /* disable dma on card */
227 devpriv->irq_dma_bits &= ~DMA_INTR_EN_BIT & ~DMA_EN_BIT;
228 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
230 /* disable computer's dma */
231 comedi_isadma_disable(desc->chan);
233 /* clear fifo and reset triggering circuitry */
234 outw(0, dev->iobase + FIFO_RESET_REG);
240 * sets bits in devpriv->clock_bits to nearest approximation of requested
241 * period, adjusts requested period to actual timing.
243 static int a2150_get_timing(struct comedi_device *dev, unsigned int *period,
246 const struct a2150_board *board = dev->board_ptr;
247 struct a2150_private *devpriv = dev->private;
249 int lub_divisor_shift, lub_index, glb_divisor_shift, glb_index;
252 /* initialize greatest lower and least upper bounds */
253 lub_divisor_shift = 3;
255 lub = board->clock[lub_index] * (1 << lub_divisor_shift);
256 glb_divisor_shift = 0;
257 glb_index = board->num_clocks - 1;
258 glb = board->clock[glb_index] * (1 << glb_divisor_shift);
260 /* make sure period is in available range */
266 /* we can multiply period by 1, 2, 4, or 8, using (1 << i) */
267 for (i = 0; i < 4; i++) {
268 /* there are a maximum of 4 master clocks */
269 for (j = 0; j < board->num_clocks; j++) {
270 /* temp is the period in nanosec we are evaluating */
271 temp = board->clock[j] * (1 << i);
272 /* if it is the best match yet */
273 if (temp < lub && temp >= *period) {
274 lub_divisor_shift = i;
278 if (temp > glb && temp <= *period) {
279 glb_divisor_shift = i;
285 switch (flags & CMDF_ROUND_MASK) {
286 case CMDF_ROUND_NEAREST:
288 /* if least upper bound is better approximation */
289 if (lub - *period < *period - glb)
297 case CMDF_ROUND_DOWN:
302 /* set clock bits for config register appropriately */
303 devpriv->config_bits &= ~CLOCK_MASK;
304 if (*period == lub) {
305 devpriv->config_bits |=
306 CLOCK_SELECT_BITS(lub_index) |
307 CLOCK_DIVISOR_BITS(lub_divisor_shift);
309 devpriv->config_bits |=
310 CLOCK_SELECT_BITS(glb_index) |
311 CLOCK_DIVISOR_BITS(glb_divisor_shift);
317 static int a2150_set_chanlist(struct comedi_device *dev,
318 unsigned int start_channel,
319 unsigned int num_channels)
321 struct a2150_private *devpriv = dev->private;
323 if (start_channel + num_channels > 4)
326 devpriv->config_bits &= ~CHANNEL_MASK;
328 switch (num_channels) {
330 devpriv->config_bits |= CHANNEL_BITS(0x4 | start_channel);
333 if (start_channel == 0)
334 devpriv->config_bits |= CHANNEL_BITS(0x2);
335 else if (start_channel == 2)
336 devpriv->config_bits |= CHANNEL_BITS(0x3);
341 devpriv->config_bits |= CHANNEL_BITS(0x1);
350 static int a2150_ai_check_chanlist(struct comedi_device *dev,
351 struct comedi_subdevice *s,
352 struct comedi_cmd *cmd)
354 unsigned int chan0 = CR_CHAN(cmd->chanlist[0]);
355 unsigned int aref0 = CR_AREF(cmd->chanlist[0]);
358 if (cmd->chanlist_len == 2 && (chan0 == 1 || chan0 == 3)) {
359 dev_dbg(dev->class_dev,
360 "length 2 chanlist must be channels 0,1 or channels 2,3\n");
364 if (cmd->chanlist_len == 3) {
365 dev_dbg(dev->class_dev,
366 "chanlist must have 1,2 or 4 channels\n");
370 for (i = 1; i < cmd->chanlist_len; i++) {
371 unsigned int chan = CR_CHAN(cmd->chanlist[i]);
372 unsigned int aref = CR_AREF(cmd->chanlist[i]);
374 if (chan != (chan0 + i)) {
375 dev_dbg(dev->class_dev,
376 "entries in chanlist must be consecutive channels, counting upwards\n");
383 dev_dbg(dev->class_dev,
384 "channels 0/1 and 2/3 must have the same analog reference\n");
392 static int a2150_ai_cmdtest(struct comedi_device *dev,
393 struct comedi_subdevice *s, struct comedi_cmd *cmd)
395 const struct a2150_board *board = dev->board_ptr;
399 /* Step 1 : check if triggers are trivially valid */
401 err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_EXT);
402 err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_TIMER);
403 err |= comedi_check_trigger_src(&cmd->convert_src, TRIG_NOW);
404 err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
405 err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
410 /* Step 2a : make sure trigger sources are unique */
412 err |= comedi_check_trigger_is_unique(cmd->start_src);
413 err |= comedi_check_trigger_is_unique(cmd->stop_src);
415 /* Step 2b : and mutually compatible */
420 /* Step 3: check if arguments are trivially valid */
422 err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
424 if (cmd->convert_src == TRIG_TIMER) {
425 err |= comedi_check_trigger_arg_min(&cmd->convert_arg,
429 err |= comedi_check_trigger_arg_min(&cmd->chanlist_len, 1);
430 err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
433 if (cmd->stop_src == TRIG_COUNT)
434 err |= comedi_check_trigger_arg_min(&cmd->stop_arg, 1);
436 err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
441 /* step 4: fix up any arguments */
443 if (cmd->scan_begin_src == TRIG_TIMER) {
444 arg = cmd->scan_begin_arg;
445 a2150_get_timing(dev, &arg, cmd->flags);
446 err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, arg);
452 /* Step 5: check channel list if it exists */
453 if (cmd->chanlist && cmd->chanlist_len > 0)
454 err |= a2150_ai_check_chanlist(dev, s, cmd);
462 static int a2150_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
464 struct a2150_private *devpriv = dev->private;
465 struct comedi_isadma *dma = devpriv->dma;
466 struct comedi_isadma_desc *desc = &dma->desc[0];
467 struct comedi_async *async = s->async;
468 struct comedi_cmd *cmd = &async->cmd;
469 unsigned int old_config_bits = devpriv->config_bits;
470 unsigned int trigger_bits;
472 if (cmd->flags & CMDF_PRIORITY) {
473 dev_err(dev->class_dev,
474 "dma incompatible with hard real-time interrupt (CMDF_PRIORITY), aborting\n");
477 /* clear fifo and reset triggering circuitry */
478 outw(0, dev->iobase + FIFO_RESET_REG);
481 if (a2150_set_chanlist(dev, CR_CHAN(cmd->chanlist[0]),
482 cmd->chanlist_len) < 0)
485 /* setup ac/dc coupling */
486 if (CR_AREF(cmd->chanlist[0]) == AREF_OTHER)
487 devpriv->config_bits |= AC0_BIT;
489 devpriv->config_bits &= ~AC0_BIT;
490 if (CR_AREF(cmd->chanlist[2]) == AREF_OTHER)
491 devpriv->config_bits |= AC1_BIT;
493 devpriv->config_bits &= ~AC1_BIT;
496 a2150_get_timing(dev, &cmd->scan_begin_arg, cmd->flags);
498 /* send timing, channel, config bits */
499 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
501 /* initialize number of samples remaining */
502 devpriv->count = cmd->stop_arg * cmd->chanlist_len;
504 comedi_isadma_disable(desc->chan);
506 /* set size of transfer to fill in 1/3 second */
507 #define ONE_THIRD_SECOND 333333333
508 desc->size = comedi_bytes_per_sample(s) * cmd->chanlist_len *
509 ONE_THIRD_SECOND / cmd->scan_begin_arg;
510 if (desc->size > desc->maxsize)
511 desc->size = desc->maxsize;
512 if (desc->size < comedi_bytes_per_sample(s))
513 desc->size = comedi_bytes_per_sample(s);
514 desc->size -= desc->size % comedi_bytes_per_sample(s);
516 comedi_isadma_program(desc);
519 * Clear dma interrupt before enabling it, to try and get rid of
520 * that one spurious interrupt that has been happening.
522 outw(0x00, dev->iobase + DMA_TC_CLEAR_REG);
524 /* enable dma on card */
525 devpriv->irq_dma_bits |= DMA_INTR_EN_BIT | DMA_EN_BIT;
526 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
528 /* may need to wait 72 sampling periods if timing was changed */
529 comedi_8254_load(dev->pacer, 2, 72, I8254_MODE0 | I8254_BINARY);
531 /* setup start triggering */
533 /* decide if we need to wait 72 periods for valid data */
534 if (cmd->start_src == TRIG_NOW &&
535 (old_config_bits & CLOCK_MASK) !=
536 (devpriv->config_bits & CLOCK_MASK)) {
537 /* set trigger source to delay trigger */
538 trigger_bits |= DELAY_TRIGGER_BITS;
540 /* otherwise no delay */
541 trigger_bits |= POST_TRIGGER_BITS;
543 /* enable external hardware trigger */
544 if (cmd->start_src == TRIG_EXT) {
545 trigger_bits |= HW_TRIG_EN;
546 } else if (cmd->start_src == TRIG_OTHER) {
548 * XXX add support for level/slope start trigger
551 dev_err(dev->class_dev, "you shouldn't see this?\n");
553 /* send trigger config bits */
554 outw(trigger_bits, dev->iobase + TRIGGER_REG);
556 /* start acquisition for soft trigger */
557 if (cmd->start_src == TRIG_NOW)
558 outw(0, dev->iobase + FIFO_START_REG);
563 static int a2150_ai_eoc(struct comedi_device *dev,
564 struct comedi_subdevice *s,
565 struct comedi_insn *insn,
566 unsigned long context)
570 status = inw(dev->iobase + STATUS_REG);
571 if (status & FNE_BIT)
576 static int a2150_ai_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
577 struct comedi_insn *insn, unsigned int *data)
579 struct a2150_private *devpriv = dev->private;
583 /* clear fifo and reset triggering circuitry */
584 outw(0, dev->iobase + FIFO_RESET_REG);
587 if (a2150_set_chanlist(dev, CR_CHAN(insn->chanspec), 1) < 0)
590 /* set dc coupling */
591 devpriv->config_bits &= ~AC0_BIT;
592 devpriv->config_bits &= ~AC1_BIT;
594 /* send timing, channel, config bits */
595 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
597 /* disable dma on card */
598 devpriv->irq_dma_bits &= ~DMA_INTR_EN_BIT & ~DMA_EN_BIT;
599 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
601 /* setup start triggering */
602 outw(0, dev->iobase + TRIGGER_REG);
604 /* start acquisition for soft trigger */
605 outw(0, dev->iobase + FIFO_START_REG);
608 * there is a 35.6 sample delay for data to get through the
611 for (n = 0; n < 36; n++) {
612 ret = comedi_timeout(dev, s, insn, a2150_ai_eoc, 0);
616 inw(dev->iobase + FIFO_DATA_REG);
620 for (n = 0; n < insn->n; n++) {
621 ret = comedi_timeout(dev, s, insn, a2150_ai_eoc, 0);
625 data[n] = inw(dev->iobase + FIFO_DATA_REG);
629 /* clear fifo and reset triggering circuitry */
630 outw(0, dev->iobase + FIFO_RESET_REG);
635 static void a2150_alloc_irq_and_dma(struct comedi_device *dev,
636 struct comedi_devconfig *it)
638 struct a2150_private *devpriv = dev->private;
639 unsigned int irq_num = it->options[1];
640 unsigned int dma_chan = it->options[2];
643 * Only IRQs 15, 14, 12-9, and 7-3 are valid.
644 * Only DMA channels 7-5 and 3-0 are valid.
646 if (irq_num > 15 || dma_chan > 7 ||
647 !((1 << irq_num) & 0xdef8) || !((1 << dma_chan) & 0xef))
650 if (request_irq(irq_num, a2150_interrupt, 0, dev->board_name, dev))
653 /* DMA uses 1 buffer */
654 devpriv->dma = comedi_isadma_alloc(dev, 1, dma_chan, dma_chan,
655 A2150_DMA_BUFFER_SIZE,
658 free_irq(irq_num, dev);
661 devpriv->irq_dma_bits = IRQ_LVL_BITS(irq_num) |
662 DMA_CHAN_BITS(dma_chan);
666 static void a2150_free_dma(struct comedi_device *dev)
668 struct a2150_private *devpriv = dev->private;
671 comedi_isadma_free(devpriv->dma);
674 static const struct a2150_board *a2150_probe(struct comedi_device *dev)
676 int id = ID_BITS(inw(dev->iobase + STATUS_REG));
678 if (id >= ARRAY_SIZE(a2150_boards))
681 return &a2150_boards[id];
684 static int a2150_attach(struct comedi_device *dev, struct comedi_devconfig *it)
686 const struct a2150_board *board;
687 struct a2150_private *devpriv;
688 struct comedi_subdevice *s;
689 static const int timeout = 2000;
693 devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
697 ret = comedi_request_region(dev, it->options[0], 0x1c);
701 board = a2150_probe(dev);
704 dev->board_ptr = board;
705 dev->board_name = board->name;
707 /* an IRQ and DMA are required to support async commands */
708 a2150_alloc_irq_and_dma(dev, it);
710 dev->pacer = comedi_8254_io_alloc(dev->iobase + I8253_BASE_REG,
712 if (IS_ERR(dev->pacer))
713 return PTR_ERR(dev->pacer);
715 ret = comedi_alloc_subdevices(dev, 1);
719 /* analog input subdevice */
720 s = &dev->subdevices[0];
721 s->type = COMEDI_SUBD_AI;
722 s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_OTHER;
725 s->range_table = &range_a2150;
726 s->insn_read = a2150_ai_rinsn;
728 dev->read_subdev = s;
729 s->subdev_flags |= SDF_CMD_READ;
730 s->len_chanlist = s->n_chan;
731 s->do_cmd = a2150_ai_cmd;
732 s->do_cmdtest = a2150_ai_cmdtest;
733 s->cancel = a2150_cancel;
736 /* set card's irq and dma levels */
737 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
739 /* reset and sync adc clock circuitry */
740 outw_p(DPD_BIT | APD_BIT, dev->iobase + CONFIG_REG);
741 outw_p(DPD_BIT, dev->iobase + CONFIG_REG);
742 /* initialize configuration register */
743 devpriv->config_bits = 0;
744 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
745 /* wait until offset calibration is done, then enable analog inputs */
746 for (i = 0; i < timeout; i++) {
747 if ((DCAL_BIT & inw(dev->iobase + STATUS_REG)) == 0)
749 usleep_range(1000, 3000);
752 dev_err(dev->class_dev,
753 "timed out waiting for offset calibration to complete\n");
756 devpriv->config_bits |= ENABLE0_BIT | ENABLE1_BIT;
757 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
762 static void a2150_detach(struct comedi_device *dev)
765 outw(APD_BIT | DPD_BIT, dev->iobase + CONFIG_REG);
767 comedi_legacy_detach(dev);
770 static struct comedi_driver ni_at_a2150_driver = {
771 .driver_name = "ni_at_a2150",
772 .module = THIS_MODULE,
773 .attach = a2150_attach,
774 .detach = a2150_detach,
776 module_comedi_driver(ni_at_a2150_driver);
778 MODULE_AUTHOR("Comedi https://www.comedi.org");
779 MODULE_DESCRIPTION("Comedi low-level driver");
780 MODULE_LICENSE("GPL");