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>
43 #include "../comedidev.h"
45 #include "comedi_isadma.h"
46 #include "comedi_8254.h"
48 #define A2150_DMA_BUFFER_SIZE 0xff00 /* size in bytes of dma buffer */
50 /* Registers and bits */
51 #define CONFIG_REG 0x0
52 #define CHANNEL_BITS(x) ((x) & 0x7)
53 #define CHANNEL_MASK 0x7
54 #define CLOCK_SELECT_BITS(x) (((x) & 0x3) << 3)
55 #define CLOCK_DIVISOR_BITS(x) (((x) & 0x3) << 5)
56 #define CLOCK_MASK (0xf << 3)
57 /* enable (don't internally ground) channels 0 and 1 */
58 #define ENABLE0_BIT 0x80
59 /* enable (don't internally ground) channels 2 and 3 */
60 #define ENABLE1_BIT 0x100
61 #define AC0_BIT 0x200 /* ac couple channels 0,1 */
62 #define AC1_BIT 0x400 /* ac couple channels 2,3 */
63 #define APD_BIT 0x800 /* analog power down */
64 #define DPD_BIT 0x1000 /* digital power down */
65 #define TRIGGER_REG 0x2 /* trigger config register */
66 #define POST_TRIGGER_BITS 0x2
67 #define DELAY_TRIGGER_BITS 0x3
68 #define HW_TRIG_EN 0x10 /* enable hardware trigger */
69 #define FIFO_START_REG 0x6 /* software start aquistion trigger */
70 #define FIFO_RESET_REG 0x8 /* clears fifo + fifo flags */
71 #define FIFO_DATA_REG 0xa /* read data */
72 #define DMA_TC_CLEAR_REG 0xe /* clear dma terminal count interrupt */
73 #define STATUS_REG 0x12 /* read only */
74 #define FNE_BIT 0x1 /* fifo not empty */
75 #define OVFL_BIT 0x8 /* fifo overflow */
76 #define EDAQ_BIT 0x10 /* end of acquisition interrupt */
77 #define DCAL_BIT 0x20 /* offset calibration in progress */
78 #define INTR_BIT 0x40 /* interrupt has occurred */
79 /* dma terminal count interrupt has occurred */
80 #define DMA_TC_BIT 0x80
81 #define ID_BITS(x) (((x) >> 8) & 0x3)
82 #define IRQ_DMA_CNTRL_REG 0x12 /* write only */
83 #define DMA_CHAN_BITS(x) ((x) & 0x7) /* sets dma channel */
84 #define DMA_EN_BIT 0x8 /* enables dma */
85 #define IRQ_LVL_BITS(x) (((x) & 0xf) << 4) /* sets irq level */
86 #define FIFO_INTR_EN_BIT 0x100 /* enable fifo interrupts */
87 #define FIFO_INTR_FHF_BIT 0x200 /* interrupt fifo half full */
88 /* enable interrupt on dma terminal count */
89 #define DMA_INTR_EN_BIT 0x800
90 #define DMA_DEM_EN_BIT 0x1000 /* enables demand mode dma */
91 #define I8253_BASE_REG 0x14
95 int clock[4]; /* master clock periods, in nanoseconds */
96 int num_clocks; /* number of available master clock speeds */
97 int ai_speed; /* maximum conversion rate in nanoseconds */
100 /* analog input range */
101 static const struct comedi_lrange range_a2150 = {
107 /* enum must match board indices */
108 enum { a2150_c, a2150_s };
109 static const struct a2150_board a2150_boards[] = {
112 .clock = {31250, 22676, 20833, 19531},
118 .clock = {62500, 50000, 41667, 0},
124 struct a2150_private {
125 struct comedi_isadma *dma;
126 unsigned int count; /* number of data points left to be taken */
127 int irq_dma_bits; /* irq/dma register bits */
128 int config_bits; /* config register bits */
131 /* interrupt service routine */
132 static irqreturn_t a2150_interrupt(int irq, void *d)
134 struct comedi_device *dev = d;
135 struct a2150_private *devpriv = dev->private;
136 struct comedi_isadma *dma = devpriv->dma;
137 struct comedi_isadma_desc *desc = &dma->desc[0];
138 struct comedi_subdevice *s = dev->read_subdev;
139 struct comedi_async *async = s->async;
140 struct comedi_cmd *cmd = &async->cmd;
141 unsigned short *buf = desc->virt_addr;
142 unsigned int max_points, num_points, residue, leftover;
150 status = inw(dev->iobase + STATUS_REG);
151 if ((status & INTR_BIT) == 0)
154 if (status & OVFL_BIT) {
155 async->events |= COMEDI_CB_ERROR;
156 comedi_handle_events(dev, s);
159 if ((status & DMA_TC_BIT) == 0) {
160 async->events |= COMEDI_CB_ERROR;
161 comedi_handle_events(dev, s);
166 * residue is the number of bytes left to be done on the dma
167 * transfer. It should always be zero at this point unless
168 * the stop_src is set to external triggering.
170 residue = comedi_isadma_disable(desc->chan);
172 /* figure out how many points to read */
173 max_points = comedi_bytes_to_samples(s, desc->size);
174 num_points = max_points - comedi_bytes_to_samples(s, residue);
175 if (devpriv->count < num_points && cmd->stop_src == TRIG_COUNT)
176 num_points = devpriv->count;
178 /* figure out how many points will be stored next time */
180 if (cmd->stop_src == TRIG_NONE) {
181 leftover = comedi_bytes_to_samples(s, desc->size);
182 } else if (devpriv->count > max_points) {
183 leftover = devpriv->count - max_points;
184 if (leftover > max_points)
185 leftover = max_points;
188 * There should only be a residue if collection was stopped by having
189 * the stop_src set to an external trigger, in which case there
190 * will be no more data
195 for (i = 0; i < num_points; i++) {
196 /* write data point to comedi buffer */
198 /* convert from 2's complement to unsigned coding */
200 comedi_buf_write_samples(s, &dpnt, 1);
201 if (cmd->stop_src == TRIG_COUNT) {
202 if (--devpriv->count == 0) { /* end of acquisition */
203 async->events |= COMEDI_CB_EOA;
210 desc->size = comedi_samples_to_bytes(s, leftover);
211 comedi_isadma_program(desc);
214 comedi_handle_events(dev, s);
216 /* clear interrupt */
217 outw(0x00, dev->iobase + DMA_TC_CLEAR_REG);
222 static int a2150_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
224 struct a2150_private *devpriv = dev->private;
225 struct comedi_isadma *dma = devpriv->dma;
226 struct comedi_isadma_desc *desc = &dma->desc[0];
228 /* disable dma on card */
229 devpriv->irq_dma_bits &= ~DMA_INTR_EN_BIT & ~DMA_EN_BIT;
230 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
232 /* disable computer's dma */
233 comedi_isadma_disable(desc->chan);
235 /* clear fifo and reset triggering circuitry */
236 outw(0, dev->iobase + FIFO_RESET_REG);
242 * sets bits in devpriv->clock_bits to nearest approximation of requested
243 * period, adjusts requested period to actual timing.
245 static int a2150_get_timing(struct comedi_device *dev, unsigned int *period,
248 const struct a2150_board *board = dev->board_ptr;
249 struct a2150_private *devpriv = dev->private;
251 int lub_divisor_shift, lub_index, glb_divisor_shift, glb_index;
254 /* initialize greatest lower and least upper bounds */
255 lub_divisor_shift = 3;
257 lub = board->clock[lub_index] * (1 << lub_divisor_shift);
258 glb_divisor_shift = 0;
259 glb_index = board->num_clocks - 1;
260 glb = board->clock[glb_index] * (1 << glb_divisor_shift);
262 /* make sure period is in available range */
268 /* we can multiply period by 1, 2, 4, or 8, using (1 << i) */
269 for (i = 0; i < 4; i++) {
270 /* there are a maximum of 4 master clocks */
271 for (j = 0; j < board->num_clocks; j++) {
272 /* temp is the period in nanosec we are evaluating */
273 temp = board->clock[j] * (1 << i);
274 /* if it is the best match yet */
275 if (temp < lub && temp >= *period) {
276 lub_divisor_shift = i;
280 if (temp > glb && temp <= *period) {
281 glb_divisor_shift = i;
287 switch (flags & CMDF_ROUND_MASK) {
288 case CMDF_ROUND_NEAREST:
290 /* if least upper bound is better approximation */
291 if (lub - *period < *period - glb)
299 case CMDF_ROUND_DOWN:
304 /* set clock bits for config register appropriately */
305 devpriv->config_bits &= ~CLOCK_MASK;
306 if (*period == lub) {
307 devpriv->config_bits |=
308 CLOCK_SELECT_BITS(lub_index) |
309 CLOCK_DIVISOR_BITS(lub_divisor_shift);
311 devpriv->config_bits |=
312 CLOCK_SELECT_BITS(glb_index) |
313 CLOCK_DIVISOR_BITS(glb_divisor_shift);
319 static int a2150_set_chanlist(struct comedi_device *dev,
320 unsigned int start_channel,
321 unsigned int num_channels)
323 struct a2150_private *devpriv = dev->private;
325 if (start_channel + num_channels > 4)
328 devpriv->config_bits &= ~CHANNEL_MASK;
330 switch (num_channels) {
332 devpriv->config_bits |= CHANNEL_BITS(0x4 | start_channel);
335 if (start_channel == 0)
336 devpriv->config_bits |= CHANNEL_BITS(0x2);
337 else if (start_channel == 2)
338 devpriv->config_bits |= CHANNEL_BITS(0x3);
343 devpriv->config_bits |= CHANNEL_BITS(0x1);
352 static int a2150_ai_check_chanlist(struct comedi_device *dev,
353 struct comedi_subdevice *s,
354 struct comedi_cmd *cmd)
356 unsigned int chan0 = CR_CHAN(cmd->chanlist[0]);
357 unsigned int aref0 = CR_AREF(cmd->chanlist[0]);
360 if (cmd->chanlist_len == 2 && (chan0 == 1 || chan0 == 3)) {
361 dev_dbg(dev->class_dev,
362 "length 2 chanlist must be channels 0,1 or channels 2,3\n");
366 if (cmd->chanlist_len == 3) {
367 dev_dbg(dev->class_dev,
368 "chanlist must have 1,2 or 4 channels\n");
372 for (i = 1; i < cmd->chanlist_len; i++) {
373 unsigned int chan = CR_CHAN(cmd->chanlist[i]);
374 unsigned int aref = CR_AREF(cmd->chanlist[i]);
376 if (chan != (chan0 + i)) {
377 dev_dbg(dev->class_dev,
378 "entries in chanlist must be consecutive channels, counting upwards\n");
385 dev_dbg(dev->class_dev,
386 "channels 0/1 and 2/3 must have the same analog reference\n");
394 static int a2150_ai_cmdtest(struct comedi_device *dev,
395 struct comedi_subdevice *s, struct comedi_cmd *cmd)
397 const struct a2150_board *board = dev->board_ptr;
401 /* Step 1 : check if triggers are trivially valid */
403 err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_EXT);
404 err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_TIMER);
405 err |= comedi_check_trigger_src(&cmd->convert_src, TRIG_NOW);
406 err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
407 err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
412 /* Step 2a : make sure trigger sources are unique */
414 err |= comedi_check_trigger_is_unique(cmd->start_src);
415 err |= comedi_check_trigger_is_unique(cmd->stop_src);
417 /* Step 2b : and mutually compatible */
422 /* Step 3: check if arguments are trivially valid */
424 err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
426 if (cmd->convert_src == TRIG_TIMER) {
427 err |= comedi_check_trigger_arg_min(&cmd->convert_arg,
431 err |= comedi_check_trigger_arg_min(&cmd->chanlist_len, 1);
432 err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
435 if (cmd->stop_src == TRIG_COUNT)
436 err |= comedi_check_trigger_arg_min(&cmd->stop_arg, 1);
438 err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
443 /* step 4: fix up any arguments */
445 if (cmd->scan_begin_src == TRIG_TIMER) {
446 arg = cmd->scan_begin_arg;
447 a2150_get_timing(dev, &arg, cmd->flags);
448 err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, arg);
454 /* Step 5: check channel list if it exists */
455 if (cmd->chanlist && cmd->chanlist_len > 0)
456 err |= a2150_ai_check_chanlist(dev, s, cmd);
464 static int a2150_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
466 struct a2150_private *devpriv = dev->private;
467 struct comedi_isadma *dma = devpriv->dma;
468 struct comedi_isadma_desc *desc = &dma->desc[0];
469 struct comedi_async *async = s->async;
470 struct comedi_cmd *cmd = &async->cmd;
471 unsigned int old_config_bits = devpriv->config_bits;
472 unsigned int trigger_bits;
474 if (cmd->flags & CMDF_PRIORITY) {
475 dev_err(dev->class_dev,
476 "dma incompatible with hard real-time interrupt (CMDF_PRIORITY), aborting\n");
479 /* clear fifo and reset triggering circuitry */
480 outw(0, dev->iobase + FIFO_RESET_REG);
483 if (a2150_set_chanlist(dev, CR_CHAN(cmd->chanlist[0]),
484 cmd->chanlist_len) < 0)
487 /* setup ac/dc coupling */
488 if (CR_AREF(cmd->chanlist[0]) == AREF_OTHER)
489 devpriv->config_bits |= AC0_BIT;
491 devpriv->config_bits &= ~AC0_BIT;
492 if (CR_AREF(cmd->chanlist[2]) == AREF_OTHER)
493 devpriv->config_bits |= AC1_BIT;
495 devpriv->config_bits &= ~AC1_BIT;
498 a2150_get_timing(dev, &cmd->scan_begin_arg, cmd->flags);
500 /* send timing, channel, config bits */
501 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
503 /* initialize number of samples remaining */
504 devpriv->count = cmd->stop_arg * cmd->chanlist_len;
506 comedi_isadma_disable(desc->chan);
508 /* set size of transfer to fill in 1/3 second */
509 #define ONE_THIRD_SECOND 333333333
510 desc->size = comedi_bytes_per_sample(s) * cmd->chanlist_len *
511 ONE_THIRD_SECOND / cmd->scan_begin_arg;
512 if (desc->size > desc->maxsize)
513 desc->size = desc->maxsize;
514 if (desc->size < comedi_bytes_per_sample(s))
515 desc->size = comedi_bytes_per_sample(s);
516 desc->size -= desc->size % comedi_bytes_per_sample(s);
518 comedi_isadma_program(desc);
521 * Clear dma interrupt before enabling it, to try and get rid of
522 * that one spurious interrupt that has been happening.
524 outw(0x00, dev->iobase + DMA_TC_CLEAR_REG);
526 /* enable dma on card */
527 devpriv->irq_dma_bits |= DMA_INTR_EN_BIT | DMA_EN_BIT;
528 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
530 /* may need to wait 72 sampling periods if timing was changed */
531 comedi_8254_load(dev->pacer, 2, 72, I8254_MODE0 | I8254_BINARY);
533 /* setup start triggering */
535 /* decide if we need to wait 72 periods for valid data */
536 if (cmd->start_src == TRIG_NOW &&
537 (old_config_bits & CLOCK_MASK) !=
538 (devpriv->config_bits & CLOCK_MASK)) {
539 /* set trigger source to delay trigger */
540 trigger_bits |= DELAY_TRIGGER_BITS;
542 /* otherwise no delay */
543 trigger_bits |= POST_TRIGGER_BITS;
545 /* enable external hardware trigger */
546 if (cmd->start_src == TRIG_EXT) {
547 trigger_bits |= HW_TRIG_EN;
548 } else if (cmd->start_src == TRIG_OTHER) {
550 * XXX add support for level/slope start trigger
553 dev_err(dev->class_dev, "you shouldn't see this?\n");
555 /* send trigger config bits */
556 outw(trigger_bits, dev->iobase + TRIGGER_REG);
558 /* start acquisition for soft trigger */
559 if (cmd->start_src == TRIG_NOW)
560 outw(0, dev->iobase + FIFO_START_REG);
565 static int a2150_ai_eoc(struct comedi_device *dev,
566 struct comedi_subdevice *s,
567 struct comedi_insn *insn,
568 unsigned long context)
572 status = inw(dev->iobase + STATUS_REG);
573 if (status & FNE_BIT)
578 static int a2150_ai_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
579 struct comedi_insn *insn, unsigned int *data)
581 struct a2150_private *devpriv = dev->private;
585 /* clear fifo and reset triggering circuitry */
586 outw(0, dev->iobase + FIFO_RESET_REG);
589 if (a2150_set_chanlist(dev, CR_CHAN(insn->chanspec), 1) < 0)
592 /* set dc coupling */
593 devpriv->config_bits &= ~AC0_BIT;
594 devpriv->config_bits &= ~AC1_BIT;
596 /* send timing, channel, config bits */
597 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
599 /* disable dma on card */
600 devpriv->irq_dma_bits &= ~DMA_INTR_EN_BIT & ~DMA_EN_BIT;
601 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
603 /* setup start triggering */
604 outw(0, dev->iobase + TRIGGER_REG);
606 /* start acquisition for soft trigger */
607 outw(0, dev->iobase + FIFO_START_REG);
610 * there is a 35.6 sample delay for data to get through the
613 for (n = 0; n < 36; n++) {
614 ret = comedi_timeout(dev, s, insn, a2150_ai_eoc, 0);
618 inw(dev->iobase + FIFO_DATA_REG);
622 for (n = 0; n < insn->n; n++) {
623 ret = comedi_timeout(dev, s, insn, a2150_ai_eoc, 0);
627 data[n] = inw(dev->iobase + FIFO_DATA_REG);
631 /* clear fifo and reset triggering circuitry */
632 outw(0, dev->iobase + FIFO_RESET_REG);
637 static void a2150_alloc_irq_and_dma(struct comedi_device *dev,
638 struct comedi_devconfig *it)
640 struct a2150_private *devpriv = dev->private;
641 unsigned int irq_num = it->options[1];
642 unsigned int dma_chan = it->options[2];
645 * Only IRQs 15, 14, 12-9, and 7-3 are valid.
646 * Only DMA channels 7-5 and 3-0 are valid.
648 if (irq_num > 15 || dma_chan > 7 ||
649 !((1 << irq_num) & 0xdef8) || !((1 << dma_chan) & 0xef))
652 if (request_irq(irq_num, a2150_interrupt, 0, dev->board_name, dev))
655 /* DMA uses 1 buffer */
656 devpriv->dma = comedi_isadma_alloc(dev, 1, dma_chan, dma_chan,
657 A2150_DMA_BUFFER_SIZE,
660 free_irq(irq_num, dev);
663 devpriv->irq_dma_bits = IRQ_LVL_BITS(irq_num) |
664 DMA_CHAN_BITS(dma_chan);
668 static void a2150_free_dma(struct comedi_device *dev)
670 struct a2150_private *devpriv = dev->private;
673 comedi_isadma_free(devpriv->dma);
676 static const struct a2150_board *a2150_probe(struct comedi_device *dev)
678 int id = ID_BITS(inw(dev->iobase + STATUS_REG));
680 if (id >= ARRAY_SIZE(a2150_boards))
683 return &a2150_boards[id];
686 static int a2150_attach(struct comedi_device *dev, struct comedi_devconfig *it)
688 const struct a2150_board *board;
689 struct a2150_private *devpriv;
690 struct comedi_subdevice *s;
691 static const int timeout = 2000;
695 devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
699 ret = comedi_request_region(dev, it->options[0], 0x1c);
703 board = a2150_probe(dev);
706 dev->board_ptr = board;
707 dev->board_name = board->name;
709 /* an IRQ and DMA are required to support async commands */
710 a2150_alloc_irq_and_dma(dev, it);
712 dev->pacer = comedi_8254_init(dev->iobase + I8253_BASE_REG,
717 ret = comedi_alloc_subdevices(dev, 1);
721 /* analog input subdevice */
722 s = &dev->subdevices[0];
723 s->type = COMEDI_SUBD_AI;
724 s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_OTHER;
727 s->range_table = &range_a2150;
728 s->insn_read = a2150_ai_rinsn;
730 dev->read_subdev = s;
731 s->subdev_flags |= SDF_CMD_READ;
732 s->len_chanlist = s->n_chan;
733 s->do_cmd = a2150_ai_cmd;
734 s->do_cmdtest = a2150_ai_cmdtest;
735 s->cancel = a2150_cancel;
738 /* set card's irq and dma levels */
739 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
741 /* reset and sync adc clock circuitry */
742 outw_p(DPD_BIT | APD_BIT, dev->iobase + CONFIG_REG);
743 outw_p(DPD_BIT, dev->iobase + CONFIG_REG);
744 /* initialize configuration register */
745 devpriv->config_bits = 0;
746 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
747 /* wait until offset calibration is done, then enable analog inputs */
748 for (i = 0; i < timeout; i++) {
749 if ((DCAL_BIT & inw(dev->iobase + STATUS_REG)) == 0)
751 usleep_range(1000, 3000);
754 dev_err(dev->class_dev,
755 "timed out waiting for offset calibration to complete\n");
758 devpriv->config_bits |= ENABLE0_BIT | ENABLE1_BIT;
759 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
764 static void a2150_detach(struct comedi_device *dev)
767 outw(APD_BIT | DPD_BIT, dev->iobase + CONFIG_REG);
769 comedi_legacy_detach(dev);
772 static struct comedi_driver ni_at_a2150_driver = {
773 .driver_name = "ni_at_a2150",
774 .module = THIS_MODULE,
775 .attach = a2150_attach,
776 .detach = a2150_detach,
778 module_comedi_driver(ni_at_a2150_driver);
780 MODULE_AUTHOR("Comedi https://www.comedi.org");
781 MODULE_DESCRIPTION("Comedi low-level driver");
782 MODULE_LICENSE("GPL");