1 /*
2     comedi/drivers/ni_at_a2150.c
3     Driver for National Instruments AT-A2150 boards
4     Copyright (C) 2001, 2002 Frank Mori Hess <fmhess@users.sourceforge.net>
5 
6     COMEDI - Linux Control and Measurement Device Interface
7     Copyright (C) 2000 David A. Schleef <ds@schleef.org>
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 /*
20 Driver: ni_at_a2150
21 Description: National Instruments AT-A2150
22 Author: Frank Mori Hess
23 Status: works
24 Devices: [National Instruments] AT-A2150C (at_a2150c), AT-2150S (at_a2150s)
25 
26 If you want to ac couple the board's inputs, use AREF_OTHER.
27 
28 Configuration options:
29   [0] - I/O port base address
30   [1] - IRQ (optional, required for timed conversions)
31   [2] - DMA (optional, required for timed conversions)
32 
33 */
34 /*
35 Yet another driver for obsolete hardware brought to you by Frank Hess.
36 Testing and debugging help provided by Dave Andruczyk.
37 
38 This driver supports the boards:
39 
40 AT-A2150C
41 AT-A2150S
42 
43 The only difference is their master clock frequencies.
44 
45 Options:
46 	[0] - base io address
47 	[1] - irq
48 	[2] - dma channel
49 
50 References (from ftp://ftp.natinst.com/support/manuals):
51 
52 	   320360.pdf  AT-A2150 User Manual
53 
54 TODO:
55 
56 analog level triggering
57 TRIG_WAKE_EOS
58 
59 */
60 
61 #include <linux/module.h>
62 #include <linux/delay.h>
63 #include <linux/interrupt.h>
64 #include <linux/slab.h>
65 #include <linux/io.h>
66 
67 #include "../comedidev.h"
68 
69 #include "comedi_isadma.h"
70 #include "comedi_8254.h"
71 
72 #define A2150_DMA_BUFFER_SIZE	0xff00	/*  size in bytes of dma buffer */
73 
74 /* Registers and bits */
75 #define CONFIG_REG		0x0
76 #define   CHANNEL_BITS(x)		((x) & 0x7)
77 #define   CHANNEL_MASK		0x7
78 #define   CLOCK_SELECT_BITS(x)		(((x) & 0x3) << 3)
79 #define   CLOCK_DIVISOR_BITS(x)		(((x) & 0x3) << 5)
80 #define   CLOCK_MASK		(0xf << 3)
81 #define   ENABLE0_BIT		0x80	/*  enable (don't internally ground) channels 0 and 1 */
82 #define   ENABLE1_BIT		0x100	/*  enable (don't internally ground) channels 2 and 3 */
83 #define   AC0_BIT		0x200	/*  ac couple channels 0,1 */
84 #define   AC1_BIT		0x400	/*  ac couple channels 2,3 */
85 #define   APD_BIT		0x800	/*  analog power down */
86 #define   DPD_BIT		0x1000	/*  digital power down */
87 #define TRIGGER_REG		0x2	/*  trigger config register */
88 #define   POST_TRIGGER_BITS		0x2
89 #define   DELAY_TRIGGER_BITS		0x3
90 #define   HW_TRIG_EN		0x10	/*  enable hardware trigger */
91 #define FIFO_START_REG		0x6	/*  software start aquistion trigger */
92 #define FIFO_RESET_REG		0x8	/*  clears fifo + fifo flags */
93 #define FIFO_DATA_REG		0xa	/*  read data */
94 #define DMA_TC_CLEAR_REG		0xe	/*  clear dma terminal count interrupt */
95 #define STATUS_REG		0x12	/*  read only */
96 #define   FNE_BIT		0x1	/*  fifo not empty */
97 #define   OVFL_BIT		0x8	/*  fifo overflow */
98 #define   EDAQ_BIT		0x10	/*  end of acquisition interrupt */
99 #define   DCAL_BIT		0x20	/*  offset calibration in progress */
100 #define   INTR_BIT		0x40	/*  interrupt has occurred */
101 #define   DMA_TC_BIT		0x80	/*  dma terminal count interrupt has occurred */
102 #define   ID_BITS(x)	(((x) >> 8) & 0x3)
103 #define IRQ_DMA_CNTRL_REG		0x12	/*  write only */
104 #define   DMA_CHAN_BITS(x)		((x) & 0x7)	/*  sets dma channel */
105 #define   DMA_EN_BIT		0x8	/*  enables dma */
106 #define   IRQ_LVL_BITS(x)		(((x) & 0xf) << 4)	/*  sets irq level */
107 #define   FIFO_INTR_EN_BIT		0x100	/*  enable fifo interrupts */
108 #define   FIFO_INTR_FHF_BIT		0x200	/*  interrupt fifo half full */
109 #define   DMA_INTR_EN_BIT 		0x800	/*  enable interrupt on dma terminal count */
110 #define   DMA_DEM_EN_BIT	0x1000	/*  enables demand mode dma */
111 #define I8253_BASE_REG		0x14
112 
113 struct a2150_board {
114 	const char *name;
115 	int clock[4];		/*  master clock periods, in nanoseconds */
116 	int num_clocks;		/*  number of available master clock speeds */
117 	int ai_speed;		/*  maximum conversion rate in nanoseconds */
118 };
119 
120 /* analog input range */
121 static const struct comedi_lrange range_a2150 = {
122 	1, {
123 		BIP_RANGE(2.828)
124 	}
125 };
126 
127 /* enum must match board indices */
128 enum { a2150_c, a2150_s };
129 static const struct a2150_board a2150_boards[] = {
130 	{
131 	 .name = "at-a2150c",
132 	 .clock = {31250, 22676, 20833, 19531},
133 	 .num_clocks = 4,
134 	 .ai_speed = 19531,
135 	 },
136 	{
137 	 .name = "at-a2150s",
138 	 .clock = {62500, 50000, 41667, 0},
139 	 .num_clocks = 3,
140 	 .ai_speed = 41667,
141 	 },
142 };
143 
144 struct a2150_private {
145 	struct comedi_isadma *dma;
146 	unsigned int count;	/* number of data points left to be taken */
147 	int irq_dma_bits;	/*  irq/dma register bits */
148 	int config_bits;	/*  config register bits */
149 };
150 
151 /* interrupt service routine */
a2150_interrupt(int irq,void * d)152 static irqreturn_t a2150_interrupt(int irq, void *d)
153 {
154 	struct comedi_device *dev = d;
155 	struct a2150_private *devpriv = dev->private;
156 	struct comedi_isadma *dma = devpriv->dma;
157 	struct comedi_isadma_desc *desc = &dma->desc[0];
158 	struct comedi_subdevice *s = dev->read_subdev;
159 	struct comedi_async *async = s->async;
160 	struct comedi_cmd *cmd = &async->cmd;
161 	unsigned short *buf = desc->virt_addr;
162 	unsigned int max_points, num_points, residue, leftover;
163 	unsigned short dpnt;
164 	int status;
165 	int i;
166 
167 	if (!dev->attached)
168 		return IRQ_HANDLED;
169 
170 	status = inw(dev->iobase + STATUS_REG);
171 	if ((status & INTR_BIT) == 0)
172 		return IRQ_NONE;
173 
174 	if (status & OVFL_BIT) {
175 		async->events |= COMEDI_CB_ERROR;
176 		comedi_handle_events(dev, s);
177 	}
178 
179 	if ((status & DMA_TC_BIT) == 0) {
180 		async->events |= COMEDI_CB_ERROR;
181 		comedi_handle_events(dev, s);
182 		return IRQ_HANDLED;
183 	}
184 
185 	/*
186 	 * residue is the number of bytes left to be done on the dma
187 	 * transfer.  It should always be zero at this point unless
188 	 * the stop_src is set to external triggering.
189 	 */
190 	residue = comedi_isadma_disable(desc->chan);
191 
192 	/*  figure out how many points to read */
193 	max_points = comedi_bytes_to_samples(s, desc->size);
194 	num_points = max_points - comedi_bytes_to_samples(s, residue);
195 	if (devpriv->count < num_points && cmd->stop_src == TRIG_COUNT)
196 		num_points = devpriv->count;
197 
198 	/*  figure out how many points will be stored next time */
199 	leftover = 0;
200 	if (cmd->stop_src == TRIG_NONE) {
201 		leftover = comedi_bytes_to_samples(s, desc->size);
202 	} else if (devpriv->count > max_points) {
203 		leftover = devpriv->count - max_points;
204 		if (leftover > max_points)
205 			leftover = max_points;
206 	}
207 	/* there should only be a residue if collection was stopped by having
208 	 * the stop_src set to an external trigger, in which case there
209 	 * will be no more data
210 	 */
211 	if (residue)
212 		leftover = 0;
213 
214 	for (i = 0; i < num_points; i++) {
215 		/* write data point to comedi buffer */
216 		dpnt = buf[i];
217 		/*  convert from 2's complement to unsigned coding */
218 		dpnt ^= 0x8000;
219 		comedi_buf_write_samples(s, &dpnt, 1);
220 		if (cmd->stop_src == TRIG_COUNT) {
221 			if (--devpriv->count == 0) {	/* end of acquisition */
222 				async->events |= COMEDI_CB_EOA;
223 				break;
224 			}
225 		}
226 	}
227 	/* re-enable dma */
228 	if (leftover) {
229 		desc->size = comedi_samples_to_bytes(s, leftover);
230 		comedi_isadma_program(desc);
231 	}
232 
233 	comedi_handle_events(dev, s);
234 
235 	/* clear interrupt */
236 	outw(0x00, dev->iobase + DMA_TC_CLEAR_REG);
237 
238 	return IRQ_HANDLED;
239 }
240 
a2150_cancel(struct comedi_device * dev,struct comedi_subdevice * s)241 static int a2150_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
242 {
243 	struct a2150_private *devpriv = dev->private;
244 	struct comedi_isadma *dma = devpriv->dma;
245 	struct comedi_isadma_desc *desc = &dma->desc[0];
246 
247 	/*  disable dma on card */
248 	devpriv->irq_dma_bits &= ~DMA_INTR_EN_BIT & ~DMA_EN_BIT;
249 	outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
250 
251 	/*  disable computer's dma */
252 	comedi_isadma_disable(desc->chan);
253 
254 	/*  clear fifo and reset triggering circuitry */
255 	outw(0, dev->iobase + FIFO_RESET_REG);
256 
257 	return 0;
258 }
259 
260 /*
261  * sets bits in devpriv->clock_bits to nearest approximation of requested
262  * period, adjusts requested period to actual timing.
263  */
a2150_get_timing(struct comedi_device * dev,unsigned int * period,unsigned int flags)264 static int a2150_get_timing(struct comedi_device *dev, unsigned int *period,
265 			    unsigned int flags)
266 {
267 	const struct a2150_board *thisboard = dev->board_ptr;
268 	struct a2150_private *devpriv = dev->private;
269 	int lub, glb, temp;
270 	int lub_divisor_shift, lub_index, glb_divisor_shift, glb_index;
271 	int i, j;
272 
273 	/*  initialize greatest lower and least upper bounds */
274 	lub_divisor_shift = 3;
275 	lub_index = 0;
276 	lub = thisboard->clock[lub_index] * (1 << lub_divisor_shift);
277 	glb_divisor_shift = 0;
278 	glb_index = thisboard->num_clocks - 1;
279 	glb = thisboard->clock[glb_index] * (1 << glb_divisor_shift);
280 
281 	/*  make sure period is in available range */
282 	if (*period < glb)
283 		*period = glb;
284 	if (*period > lub)
285 		*period = lub;
286 
287 	/*  we can multiply period by 1, 2, 4, or 8, using (1 << i) */
288 	for (i = 0; i < 4; i++) {
289 		/*  there are a maximum of 4 master clocks */
290 		for (j = 0; j < thisboard->num_clocks; j++) {
291 			/*  temp is the period in nanosec we are evaluating */
292 			temp = thisboard->clock[j] * (1 << i);
293 			/*  if it is the best match yet */
294 			if (temp < lub && temp >= *period) {
295 				lub_divisor_shift = i;
296 				lub_index = j;
297 				lub = temp;
298 			}
299 			if (temp > glb && temp <= *period) {
300 				glb_divisor_shift = i;
301 				glb_index = j;
302 				glb = temp;
303 			}
304 		}
305 	}
306 	switch (flags & CMDF_ROUND_MASK) {
307 	case CMDF_ROUND_NEAREST:
308 	default:
309 		/*  if least upper bound is better approximation */
310 		if (lub - *period < *period - glb)
311 			*period = lub;
312 		else
313 			*period = glb;
314 		break;
315 	case CMDF_ROUND_UP:
316 		*period = lub;
317 		break;
318 	case CMDF_ROUND_DOWN:
319 		*period = glb;
320 		break;
321 	}
322 
323 	/*  set clock bits for config register appropriately */
324 	devpriv->config_bits &= ~CLOCK_MASK;
325 	if (*period == lub) {
326 		devpriv->config_bits |=
327 		    CLOCK_SELECT_BITS(lub_index) |
328 		    CLOCK_DIVISOR_BITS(lub_divisor_shift);
329 	} else {
330 		devpriv->config_bits |=
331 		    CLOCK_SELECT_BITS(glb_index) |
332 		    CLOCK_DIVISOR_BITS(glb_divisor_shift);
333 	}
334 
335 	return 0;
336 }
337 
a2150_set_chanlist(struct comedi_device * dev,unsigned int start_channel,unsigned int num_channels)338 static int a2150_set_chanlist(struct comedi_device *dev,
339 			      unsigned int start_channel,
340 			      unsigned int num_channels)
341 {
342 	struct a2150_private *devpriv = dev->private;
343 
344 	if (start_channel + num_channels > 4)
345 		return -1;
346 
347 	devpriv->config_bits &= ~CHANNEL_MASK;
348 
349 	switch (num_channels) {
350 	case 1:
351 		devpriv->config_bits |= CHANNEL_BITS(0x4 | start_channel);
352 		break;
353 	case 2:
354 		if (start_channel == 0)
355 			devpriv->config_bits |= CHANNEL_BITS(0x2);
356 		else if (start_channel == 2)
357 			devpriv->config_bits |= CHANNEL_BITS(0x3);
358 		else
359 			return -1;
360 		break;
361 	case 4:
362 		devpriv->config_bits |= CHANNEL_BITS(0x1);
363 		break;
364 	default:
365 		return -1;
366 	}
367 
368 	return 0;
369 }
370 
a2150_ai_check_chanlist(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_cmd * cmd)371 static int a2150_ai_check_chanlist(struct comedi_device *dev,
372 				   struct comedi_subdevice *s,
373 				   struct comedi_cmd *cmd)
374 {
375 	unsigned int chan0 = CR_CHAN(cmd->chanlist[0]);
376 	unsigned int aref0 = CR_AREF(cmd->chanlist[0]);
377 	int i;
378 
379 	if (cmd->chanlist_len == 2 && (chan0 == 1 || chan0 == 3)) {
380 		dev_dbg(dev->class_dev,
381 			"length 2 chanlist must be channels 0,1 or channels 2,3\n");
382 		return -EINVAL;
383 	}
384 
385 	if (cmd->chanlist_len == 3) {
386 		dev_dbg(dev->class_dev,
387 			"chanlist must have 1,2 or 4 channels\n");
388 		return -EINVAL;
389 	}
390 
391 	for (i = 1; i < cmd->chanlist_len; i++) {
392 		unsigned int chan = CR_CHAN(cmd->chanlist[i]);
393 		unsigned int aref = CR_AREF(cmd->chanlist[i]);
394 
395 		if (chan != (chan0 + i)) {
396 			dev_dbg(dev->class_dev,
397 				"entries in chanlist must be consecutive channels, counting upwards\n");
398 			return -EINVAL;
399 		}
400 
401 		if (chan == 2)
402 			aref0 = aref;
403 		if (aref != aref0) {
404 			dev_dbg(dev->class_dev,
405 				"channels 0/1 and 2/3 must have the same analog reference\n");
406 			return -EINVAL;
407 		}
408 	}
409 
410 	return 0;
411 }
412 
a2150_ai_cmdtest(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_cmd * cmd)413 static int a2150_ai_cmdtest(struct comedi_device *dev,
414 			    struct comedi_subdevice *s, struct comedi_cmd *cmd)
415 {
416 	const struct a2150_board *thisboard = dev->board_ptr;
417 	int err = 0;
418 	unsigned int arg;
419 
420 	/* Step 1 : check if triggers are trivially valid */
421 
422 	err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW | TRIG_EXT);
423 	err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_TIMER);
424 	err |= comedi_check_trigger_src(&cmd->convert_src, TRIG_NOW);
425 	err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
426 	err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
427 
428 	if (err)
429 		return 1;
430 
431 	/* Step 2a : make sure trigger sources are unique */
432 
433 	err |= comedi_check_trigger_is_unique(cmd->start_src);
434 	err |= comedi_check_trigger_is_unique(cmd->stop_src);
435 
436 	/* Step 2b : and mutually compatible */
437 
438 	if (err)
439 		return 2;
440 
441 	/* Step 3: check if arguments are trivially valid */
442 
443 	err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
444 
445 	if (cmd->convert_src == TRIG_TIMER) {
446 		err |= comedi_check_trigger_arg_min(&cmd->convert_arg,
447 						    thisboard->ai_speed);
448 	}
449 
450 	err |= comedi_check_trigger_arg_min(&cmd->chanlist_len, 1);
451 	err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
452 					   cmd->chanlist_len);
453 
454 	if (cmd->stop_src == TRIG_COUNT)
455 		err |= comedi_check_trigger_arg_min(&cmd->stop_arg, 1);
456 	else	/* TRIG_NONE */
457 		err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
458 
459 	if (err)
460 		return 3;
461 
462 	/* step 4: fix up any arguments */
463 
464 	if (cmd->scan_begin_src == TRIG_TIMER) {
465 		arg = cmd->scan_begin_arg;
466 		a2150_get_timing(dev, &arg, cmd->flags);
467 		err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, arg);
468 	}
469 
470 	if (err)
471 		return 4;
472 
473 	/* Step 5: check channel list if it exists */
474 	if (cmd->chanlist && cmd->chanlist_len > 0)
475 		err |= a2150_ai_check_chanlist(dev, s, cmd);
476 
477 	if (err)
478 		return 5;
479 
480 	return 0;
481 }
482 
a2150_ai_cmd(struct comedi_device * dev,struct comedi_subdevice * s)483 static int a2150_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
484 {
485 	struct a2150_private *devpriv = dev->private;
486 	struct comedi_isadma *dma = devpriv->dma;
487 	struct comedi_isadma_desc *desc = &dma->desc[0];
488 	struct comedi_async *async = s->async;
489 	struct comedi_cmd *cmd = &async->cmd;
490 	unsigned int old_config_bits = devpriv->config_bits;
491 	unsigned int trigger_bits;
492 
493 	if (cmd->flags & CMDF_PRIORITY) {
494 		dev_err(dev->class_dev,
495 			"dma incompatible with hard real-time interrupt (CMDF_PRIORITY), aborting\n");
496 		return -1;
497 	}
498 	/*  clear fifo and reset triggering circuitry */
499 	outw(0, dev->iobase + FIFO_RESET_REG);
500 
501 	/* setup chanlist */
502 	if (a2150_set_chanlist(dev, CR_CHAN(cmd->chanlist[0]),
503 			       cmd->chanlist_len) < 0)
504 		return -1;
505 
506 	/*  setup ac/dc coupling */
507 	if (CR_AREF(cmd->chanlist[0]) == AREF_OTHER)
508 		devpriv->config_bits |= AC0_BIT;
509 	else
510 		devpriv->config_bits &= ~AC0_BIT;
511 	if (CR_AREF(cmd->chanlist[2]) == AREF_OTHER)
512 		devpriv->config_bits |= AC1_BIT;
513 	else
514 		devpriv->config_bits &= ~AC1_BIT;
515 
516 	/*  setup timing */
517 	a2150_get_timing(dev, &cmd->scan_begin_arg, cmd->flags);
518 
519 	/*  send timing, channel, config bits */
520 	outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
521 
522 	/*  initialize number of samples remaining */
523 	devpriv->count = cmd->stop_arg * cmd->chanlist_len;
524 
525 	comedi_isadma_disable(desc->chan);
526 
527 	/*  set size of transfer to fill in 1/3 second */
528 #define ONE_THIRD_SECOND 333333333
529 	desc->size = comedi_bytes_per_sample(s) * cmd->chanlist_len *
530 		    ONE_THIRD_SECOND / cmd->scan_begin_arg;
531 	if (desc->size > desc->maxsize)
532 		desc->size = desc->maxsize;
533 	if (desc->size < comedi_bytes_per_sample(s))
534 		desc->size = comedi_bytes_per_sample(s);
535 	desc->size -= desc->size % comedi_bytes_per_sample(s);
536 
537 	comedi_isadma_program(desc);
538 
539 	/* clear dma interrupt before enabling it, to try and get rid of that
540 	 * one spurious interrupt that has been happening */
541 	outw(0x00, dev->iobase + DMA_TC_CLEAR_REG);
542 
543 	/*  enable dma on card */
544 	devpriv->irq_dma_bits |= DMA_INTR_EN_BIT | DMA_EN_BIT;
545 	outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
546 
547 	/*  may need to wait 72 sampling periods if timing was changed */
548 	comedi_8254_load(dev->pacer, 2, 72, I8254_MODE0 | I8254_BINARY);
549 
550 	/*  setup start triggering */
551 	trigger_bits = 0;
552 	/*  decide if we need to wait 72 periods for valid data */
553 	if (cmd->start_src == TRIG_NOW &&
554 	    (old_config_bits & CLOCK_MASK) !=
555 	    (devpriv->config_bits & CLOCK_MASK)) {
556 		/*  set trigger source to delay trigger */
557 		trigger_bits |= DELAY_TRIGGER_BITS;
558 	} else {
559 		/*  otherwise no delay */
560 		trigger_bits |= POST_TRIGGER_BITS;
561 	}
562 	/*  enable external hardware trigger */
563 	if (cmd->start_src == TRIG_EXT) {
564 		trigger_bits |= HW_TRIG_EN;
565 	} else if (cmd->start_src == TRIG_OTHER) {
566 		/*  XXX add support for level/slope start trigger using TRIG_OTHER */
567 		dev_err(dev->class_dev, "you shouldn't see this?\n");
568 	}
569 	/*  send trigger config bits */
570 	outw(trigger_bits, dev->iobase + TRIGGER_REG);
571 
572 	/*  start acquisition for soft trigger */
573 	if (cmd->start_src == TRIG_NOW)
574 		outw(0, dev->iobase + FIFO_START_REG);
575 
576 	return 0;
577 }
578 
a2150_ai_eoc(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned long context)579 static int a2150_ai_eoc(struct comedi_device *dev,
580 			struct comedi_subdevice *s,
581 			struct comedi_insn *insn,
582 			unsigned long context)
583 {
584 	unsigned int status;
585 
586 	status = inw(dev->iobase + STATUS_REG);
587 	if (status & FNE_BIT)
588 		return 0;
589 	return -EBUSY;
590 }
591 
a2150_ai_rinsn(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)592 static int a2150_ai_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
593 			  struct comedi_insn *insn, unsigned int *data)
594 {
595 	struct a2150_private *devpriv = dev->private;
596 	unsigned int n;
597 	int ret;
598 
599 	/*  clear fifo and reset triggering circuitry */
600 	outw(0, dev->iobase + FIFO_RESET_REG);
601 
602 	/* setup chanlist */
603 	if (a2150_set_chanlist(dev, CR_CHAN(insn->chanspec), 1) < 0)
604 		return -1;
605 
606 	/*  set dc coupling */
607 	devpriv->config_bits &= ~AC0_BIT;
608 	devpriv->config_bits &= ~AC1_BIT;
609 
610 	/*  send timing, channel, config bits */
611 	outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
612 
613 	/*  disable dma on card */
614 	devpriv->irq_dma_bits &= ~DMA_INTR_EN_BIT & ~DMA_EN_BIT;
615 	outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
616 
617 	/*  setup start triggering */
618 	outw(0, dev->iobase + TRIGGER_REG);
619 
620 	/*  start acquisition for soft trigger */
621 	outw(0, dev->iobase + FIFO_START_REG);
622 
623 	/*
624 	 * there is a 35.6 sample delay for data to get through the
625 	 * antialias filter
626 	 */
627 	for (n = 0; n < 36; n++) {
628 		ret = comedi_timeout(dev, s, insn, a2150_ai_eoc, 0);
629 		if (ret)
630 			return ret;
631 
632 		inw(dev->iobase + FIFO_DATA_REG);
633 	}
634 
635 	/*  read data */
636 	for (n = 0; n < insn->n; n++) {
637 		ret = comedi_timeout(dev, s, insn, a2150_ai_eoc, 0);
638 		if (ret)
639 			return ret;
640 
641 		data[n] = inw(dev->iobase + FIFO_DATA_REG);
642 		data[n] ^= 0x8000;
643 	}
644 
645 	/*  clear fifo and reset triggering circuitry */
646 	outw(0, dev->iobase + FIFO_RESET_REG);
647 
648 	return n;
649 }
650 
a2150_alloc_irq_and_dma(struct comedi_device * dev,struct comedi_devconfig * it)651 static void a2150_alloc_irq_and_dma(struct comedi_device *dev,
652 				    struct comedi_devconfig *it)
653 {
654 	struct a2150_private *devpriv = dev->private;
655 	unsigned int irq_num = it->options[1];
656 	unsigned int dma_chan = it->options[2];
657 
658 	/*
659 	 * Only IRQs 15, 14, 12-9, and 7-3 are valid.
660 	 * Only DMA channels 7-5 and 3-0 are valid.
661 	 */
662 	if (irq_num > 15 || dma_chan > 7 ||
663 	    !((1 << irq_num) & 0xdef8) || !((1 << dma_chan) & 0xef))
664 		return;
665 
666 	if (request_irq(irq_num, a2150_interrupt, 0, dev->board_name, dev))
667 		return;
668 
669 	/* DMA uses 1 buffer */
670 	devpriv->dma = comedi_isadma_alloc(dev, 1, dma_chan, dma_chan,
671 					   A2150_DMA_BUFFER_SIZE,
672 					   COMEDI_ISADMA_READ);
673 	if (!devpriv->dma) {
674 		free_irq(irq_num, dev);
675 	} else {
676 		dev->irq = irq_num;
677 		devpriv->irq_dma_bits = IRQ_LVL_BITS(irq_num) |
678 					DMA_CHAN_BITS(dma_chan);
679 	}
680 }
681 
a2150_free_dma(struct comedi_device * dev)682 static void a2150_free_dma(struct comedi_device *dev)
683 {
684 	struct a2150_private *devpriv = dev->private;
685 
686 	if (devpriv)
687 		comedi_isadma_free(devpriv->dma);
688 }
689 
690 /* probes board type, returns offset */
a2150_probe(struct comedi_device * dev)691 static int a2150_probe(struct comedi_device *dev)
692 {
693 	int status = inw(dev->iobase + STATUS_REG);
694 
695 	return ID_BITS(status);
696 }
697 
a2150_attach(struct comedi_device * dev,struct comedi_devconfig * it)698 static int a2150_attach(struct comedi_device *dev, struct comedi_devconfig *it)
699 {
700 	const struct a2150_board *thisboard;
701 	struct a2150_private *devpriv;
702 	struct comedi_subdevice *s;
703 	static const int timeout = 2000;
704 	int i;
705 	int ret;
706 
707 	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
708 	if (!devpriv)
709 		return -ENOMEM;
710 
711 	ret = comedi_request_region(dev, it->options[0], 0x1c);
712 	if (ret)
713 		return ret;
714 
715 	i = a2150_probe(dev);
716 	if (i >= ARRAY_SIZE(a2150_boards))
717 		return -ENODEV;
718 
719 	dev->board_ptr = a2150_boards + i;
720 	thisboard = dev->board_ptr;
721 	dev->board_name = thisboard->name;
722 
723 	/* an IRQ and DMA are required to support async commands */
724 	a2150_alloc_irq_and_dma(dev, it);
725 
726 	dev->pacer = comedi_8254_init(dev->iobase + I8253_BASE_REG,
727 				      0, I8254_IO8, 0);
728 	if (!dev->pacer)
729 		return -ENOMEM;
730 
731 	ret = comedi_alloc_subdevices(dev, 1);
732 	if (ret)
733 		return ret;
734 
735 	/* analog input subdevice */
736 	s = &dev->subdevices[0];
737 	s->type = COMEDI_SUBD_AI;
738 	s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_OTHER;
739 	s->n_chan = 4;
740 	s->maxdata = 0xffff;
741 	s->range_table = &range_a2150;
742 	s->insn_read = a2150_ai_rinsn;
743 	if (dev->irq) {
744 		dev->read_subdev = s;
745 		s->subdev_flags |= SDF_CMD_READ;
746 		s->len_chanlist = s->n_chan;
747 		s->do_cmd = a2150_ai_cmd;
748 		s->do_cmdtest = a2150_ai_cmdtest;
749 		s->cancel = a2150_cancel;
750 	}
751 
752 	/*  set card's irq and dma levels */
753 	outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
754 
755 	/*  reset and sync adc clock circuitry */
756 	outw_p(DPD_BIT | APD_BIT, dev->iobase + CONFIG_REG);
757 	outw_p(DPD_BIT, dev->iobase + CONFIG_REG);
758 	/*  initialize configuration register */
759 	devpriv->config_bits = 0;
760 	outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
761 	/*  wait until offset calibration is done, then enable analog inputs */
762 	for (i = 0; i < timeout; i++) {
763 		if ((DCAL_BIT & inw(dev->iobase + STATUS_REG)) == 0)
764 			break;
765 		udelay(1000);
766 	}
767 	if (i == timeout) {
768 		dev_err(dev->class_dev,
769 			"timed out waiting for offset calibration to complete\n");
770 		return -ETIME;
771 	}
772 	devpriv->config_bits |= ENABLE0_BIT | ENABLE1_BIT;
773 	outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
774 
775 	return 0;
776 };
777 
a2150_detach(struct comedi_device * dev)778 static void a2150_detach(struct comedi_device *dev)
779 {
780 	if (dev->iobase)
781 		outw(APD_BIT | DPD_BIT, dev->iobase + CONFIG_REG);
782 	a2150_free_dma(dev);
783 	comedi_legacy_detach(dev);
784 };
785 
786 static struct comedi_driver ni_at_a2150_driver = {
787 	.driver_name	= "ni_at_a2150",
788 	.module		= THIS_MODULE,
789 	.attach		= a2150_attach,
790 	.detach		= a2150_detach,
791 };
792 module_comedi_driver(ni_at_a2150_driver);
793 
794 MODULE_AUTHOR("Comedi http://www.comedi.org");
795 MODULE_DESCRIPTION("Comedi low-level driver");
796 MODULE_LICENSE("GPL");
797