Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux...
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / staging / comedi / drivers / ni_at_a2150.c
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 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: ni_at_a2150
27 Description: National Instruments AT-A2150
28 Author: Frank Mori Hess
29 Status: works
30 Devices: [National Instruments] AT-A2150C (at_a2150c), AT-2150S (at_a2150s)
31
32 If you want to ac couple the board's inputs, use AREF_OTHER.
33
34 Configuration options:
35 [0] - I/O port base address
36 [1] - IRQ (optional, required for timed conversions)
37 [2] - DMA (optional, required for timed conversions)
38
39 */
40 /*
41 Yet another driver for obsolete hardware brought to you by Frank Hess.
42 Testing and debugging help provided by Dave Andruczyk.
43
44 This driver supports the boards:
45
46 AT-A2150C
47 AT-A2150S
48
49 The only difference is their master clock frequencies.
50
51 Options:
52 [0] - base io address
53 [1] - irq
54 [2] - dma channel
55
56 References (from ftp://ftp.natinst.com/support/manuals):
57
58 320360.pdf AT-A2150 User Manual
59
60 TODO:
61
62 analog level triggering
63 TRIG_WAKE_EOS
64
65 */
66
67 #include <linux/interrupt.h>
68 #include <linux/slab.h>
69 #include "../comedidev.h"
70
71 #include <linux/ioport.h>
72 #include <asm/dma.h>
73
74 #include "8253.h"
75 #include "comedi_fc.h"
76
77 #define A2150_SIZE 28
78 #define A2150_DMA_BUFFER_SIZE 0xff00 /* size in bytes of dma buffer */
79
80 /* #define A2150_DEBUG enable debugging code */
81 #undef A2150_DEBUG /* disable debugging code */
82
83 /* Registers and bits */
84 #define CONFIG_REG 0x0
85 #define CHANNEL_BITS(x) ((x) & 0x7)
86 #define CHANNEL_MASK 0x7
87 #define CLOCK_SELECT_BITS(x) (((x) & 0x3) << 3)
88 #define CLOCK_DIVISOR_BITS(x) (((x) & 0x3) << 5)
89 #define CLOCK_MASK (0xf << 3)
90 #define ENABLE0_BIT 0x80 /* enable (don't internally ground) channels 0 and 1 */
91 #define ENABLE1_BIT 0x100 /* enable (don't internally ground) channels 2 and 3 */
92 #define AC0_BIT 0x200 /* ac couple channels 0,1 */
93 #define AC1_BIT 0x400 /* ac couple channels 2,3 */
94 #define APD_BIT 0x800 /* analog power down */
95 #define DPD_BIT 0x1000 /* digital power down */
96 #define TRIGGER_REG 0x2 /* trigger config register */
97 #define POST_TRIGGER_BITS 0x2
98 #define DELAY_TRIGGER_BITS 0x3
99 #define HW_TRIG_EN 0x10 /* enable hardware trigger */
100 #define FIFO_START_REG 0x6 /* software start aquistion trigger */
101 #define FIFO_RESET_REG 0x8 /* clears fifo + fifo flags */
102 #define FIFO_DATA_REG 0xa /* read data */
103 #define DMA_TC_CLEAR_REG 0xe /* clear dma terminal count interrupt */
104 #define STATUS_REG 0x12 /* read only */
105 #define FNE_BIT 0x1 /* fifo not empty */
106 #define OVFL_BIT 0x8 /* fifo overflow */
107 #define EDAQ_BIT 0x10 /* end of aquisition interrupt */
108 #define DCAL_BIT 0x20 /* offset calibration in progress */
109 #define INTR_BIT 0x40 /* interrupt has occured */
110 #define DMA_TC_BIT 0x80 /* dma terminal count interrupt has occured */
111 #define ID_BITS(x) (((x) >> 8) & 0x3)
112 #define IRQ_DMA_CNTRL_REG 0x12 /* write only */
113 #define DMA_CHAN_BITS(x) ((x) & 0x7) /* sets dma channel */
114 #define DMA_EN_BIT 0x8 /* enables dma */
115 #define IRQ_LVL_BITS(x) (((x) & 0xf) << 4) /* sets irq level */
116 #define FIFO_INTR_EN_BIT 0x100 /* enable fifo interrupts */
117 #define FIFO_INTR_FHF_BIT 0x200 /* interrupt fifo half full */
118 #define DMA_INTR_EN_BIT 0x800 /* enable interrupt on dma terminal count */
119 #define DMA_DEM_EN_BIT 0x1000 /* enables demand mode dma */
120 #define I8253_BASE_REG 0x14
121 #define I8253_MODE_REG 0x17
122 #define HW_COUNT_DISABLE 0x30 /* disable hardware counting of conversions */
123
124 struct a2150_board {
125 const char *name;
126 int clock[4]; /* master clock periods, in nanoseconds */
127 int num_clocks; /* number of available master clock speeds */
128 int ai_speed; /* maximum conversion rate in nanoseconds */
129 };
130
131 /* analog input range */
132 static const struct comedi_lrange range_a2150 = {
133 1,
134 {
135 RANGE(-2.828, 2.828),
136 }
137 };
138
139 /* enum must match board indices */
140 enum { a2150_c, a2150_s };
141 static const struct a2150_board a2150_boards[] = {
142 {
143 .name = "at-a2150c",
144 .clock = {31250, 22676, 20833, 19531},
145 .num_clocks = 4,
146 .ai_speed = 19531,
147 },
148 {
149 .name = "at-a2150s",
150 .clock = {62500, 50000, 41667, 0},
151 .num_clocks = 3,
152 .ai_speed = 41667,
153 },
154 };
155
156 /*
157 * Useful for shorthand access to the particular board structure
158 */
159 #define thisboard ((const struct a2150_board *)dev->board_ptr)
160
161 struct a2150_private {
162
163 volatile unsigned int count; /* number of data points left to be taken */
164 unsigned int dma; /* dma channel */
165 s16 *dma_buffer; /* dma buffer */
166 unsigned int dma_transfer_size; /* size in bytes of dma transfers */
167 int irq_dma_bits; /* irq/dma register bits */
168 int config_bits; /* config register bits */
169 };
170
171 #define devpriv ((struct a2150_private *)dev->private)
172
173 static int a2150_attach(struct comedi_device *dev, struct comedi_devconfig *it);
174 static int a2150_detach(struct comedi_device *dev);
175 static int a2150_cancel(struct comedi_device *dev, struct comedi_subdevice *s);
176
177 static struct comedi_driver driver_a2150 = {
178 .driver_name = "ni_at_a2150",
179 .module = THIS_MODULE,
180 .attach = a2150_attach,
181 .detach = a2150_detach,
182 };
183
184 static irqreturn_t a2150_interrupt(int irq, void *d);
185 static int a2150_ai_cmdtest(struct comedi_device *dev,
186 struct comedi_subdevice *s, struct comedi_cmd *cmd);
187 static int a2150_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s);
188 static int a2150_ai_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
189 struct comedi_insn *insn, unsigned int *data);
190 static int a2150_get_timing(struct comedi_device *dev, unsigned int *period,
191 int flags);
192 static int a2150_probe(struct comedi_device *dev);
193 static int a2150_set_chanlist(struct comedi_device *dev,
194 unsigned int start_channel,
195 unsigned int num_channels);
196 /*
197 * A convenient macro that defines init_module() and cleanup_module(),
198 * as necessary.
199 */
200 static int __init driver_a2150_init_module(void)
201 {
202 return comedi_driver_register(&driver_a2150);
203 }
204
205 static void __exit driver_a2150_cleanup_module(void)
206 {
207 comedi_driver_unregister(&driver_a2150);
208 }
209
210 module_init(driver_a2150_init_module);
211 module_exit(driver_a2150_cleanup_module);
212
213 #ifdef A2150_DEBUG
214
215 static void ni_dump_regs(struct comedi_device *dev)
216 {
217 printk("config bits 0x%x\n", devpriv->config_bits);
218 printk("irq dma bits 0x%x\n", devpriv->irq_dma_bits);
219 printk("status bits 0x%x\n", inw(dev->iobase + STATUS_REG));
220 }
221
222 #endif
223
224 /* interrupt service routine */
225 static irqreturn_t a2150_interrupt(int irq, void *d)
226 {
227 int i;
228 int status;
229 unsigned long flags;
230 struct comedi_device *dev = d;
231 struct comedi_subdevice *s = dev->read_subdev;
232 struct comedi_async *async;
233 struct comedi_cmd *cmd;
234 unsigned int max_points, num_points, residue, leftover;
235 short dpnt;
236 static const int sample_size = sizeof(devpriv->dma_buffer[0]);
237
238 if (dev->attached == 0) {
239 comedi_error(dev, "premature interrupt");
240 return IRQ_HANDLED;
241 }
242 /* initialize async here to make sure s is not NULL */
243 async = s->async;
244 async->events = 0;
245 cmd = &async->cmd;
246
247 status = inw(dev->iobase + STATUS_REG);
248
249 if ((status & INTR_BIT) == 0) {
250 comedi_error(dev, "spurious interrupt");
251 return IRQ_NONE;
252 }
253
254 if (status & OVFL_BIT) {
255 comedi_error(dev, "fifo overflow");
256 a2150_cancel(dev, s);
257 async->events |= COMEDI_CB_ERROR | COMEDI_CB_EOA;
258 }
259
260 if ((status & DMA_TC_BIT) == 0) {
261 comedi_error(dev, "caught non-dma interrupt? Aborting.");
262 a2150_cancel(dev, s);
263 async->events |= COMEDI_CB_ERROR | COMEDI_CB_EOA;
264 comedi_event(dev, s);
265 return IRQ_HANDLED;
266 }
267
268 flags = claim_dma_lock();
269 disable_dma(devpriv->dma);
270 /* clear flip-flop to make sure 2-byte registers for
271 * count and address get set correctly */
272 clear_dma_ff(devpriv->dma);
273
274 /* figure out how many points to read */
275 max_points = devpriv->dma_transfer_size / sample_size;
276 /* residue is the number of points left to be done on the dma
277 * transfer. It should always be zero at this point unless
278 * the stop_src is set to external triggering.
279 */
280 residue = get_dma_residue(devpriv->dma) / sample_size;
281 num_points = max_points - residue;
282 if (devpriv->count < num_points && cmd->stop_src == TRIG_COUNT)
283 num_points = devpriv->count;
284
285 /* figure out how many points will be stored next time */
286 leftover = 0;
287 if (cmd->stop_src == TRIG_NONE) {
288 leftover = devpriv->dma_transfer_size / sample_size;
289 } else if (devpriv->count > max_points) {
290 leftover = devpriv->count - max_points;
291 if (leftover > max_points)
292 leftover = max_points;
293 }
294 /* there should only be a residue if collection was stopped by having
295 * the stop_src set to an external trigger, in which case there
296 * will be no more data
297 */
298 if (residue)
299 leftover = 0;
300
301 for (i = 0; i < num_points; i++) {
302 /* write data point to comedi buffer */
303 dpnt = devpriv->dma_buffer[i];
304 /* convert from 2's complement to unsigned coding */
305 dpnt ^= 0x8000;
306 cfc_write_to_buffer(s, dpnt);
307 if (cmd->stop_src == TRIG_COUNT) {
308 if (--devpriv->count == 0) { /* end of acquisition */
309 a2150_cancel(dev, s);
310 async->events |= COMEDI_CB_EOA;
311 break;
312 }
313 }
314 }
315 /* re-enable dma */
316 if (leftover) {
317 set_dma_addr(devpriv->dma, virt_to_bus(devpriv->dma_buffer));
318 set_dma_count(devpriv->dma, leftover * sample_size);
319 enable_dma(devpriv->dma);
320 }
321 release_dma_lock(flags);
322
323 async->events |= COMEDI_CB_BLOCK;
324
325 comedi_event(dev, s);
326
327 /* clear interrupt */
328 outw(0x00, dev->iobase + DMA_TC_CLEAR_REG);
329
330 return IRQ_HANDLED;
331 }
332
333 /* probes board type, returns offset */
334 static int a2150_probe(struct comedi_device *dev)
335 {
336 int status = inw(dev->iobase + STATUS_REG);
337 return ID_BITS(status);
338 }
339
340 static int a2150_attach(struct comedi_device *dev, struct comedi_devconfig *it)
341 {
342 struct comedi_subdevice *s;
343 unsigned long iobase = it->options[0];
344 unsigned int irq = it->options[1];
345 unsigned int dma = it->options[2];
346 static const int timeout = 2000;
347 int i;
348
349 printk("comedi%d: %s: io 0x%lx", dev->minor, driver_a2150.driver_name,
350 iobase);
351 if (irq) {
352 printk(", irq %u", irq);
353 } else {
354 printk(", no irq");
355 }
356 if (dma) {
357 printk(", dma %u", dma);
358 } else {
359 printk(", no dma");
360 }
361 printk("\n");
362
363 /* allocate and initialize dev->private */
364 if (alloc_private(dev, sizeof(struct a2150_private)) < 0)
365 return -ENOMEM;
366
367 if (iobase == 0) {
368 printk(" io base address required\n");
369 return -EINVAL;
370 }
371
372 /* check if io addresses are available */
373 if (!request_region(iobase, A2150_SIZE, driver_a2150.driver_name)) {
374 printk(" I/O port conflict\n");
375 return -EIO;
376 }
377 dev->iobase = iobase;
378
379 /* grab our IRQ */
380 if (irq) {
381 /* check that irq is supported */
382 if (irq < 3 || irq == 8 || irq == 13 || irq > 15) {
383 printk(" invalid irq line %u\n", irq);
384 return -EINVAL;
385 }
386 if (request_irq(irq, a2150_interrupt, 0,
387 driver_a2150.driver_name, dev)) {
388 printk("unable to allocate irq %u\n", irq);
389 return -EINVAL;
390 }
391 devpriv->irq_dma_bits |= IRQ_LVL_BITS(irq);
392 dev->irq = irq;
393 }
394 /* initialize dma */
395 if (dma) {
396 if (dma == 4 || dma > 7) {
397 printk(" invalid dma channel %u\n", dma);
398 return -EINVAL;
399 }
400 if (request_dma(dma, driver_a2150.driver_name)) {
401 printk(" failed to allocate dma channel %u\n", dma);
402 return -EINVAL;
403 }
404 devpriv->dma = dma;
405 devpriv->dma_buffer =
406 kmalloc(A2150_DMA_BUFFER_SIZE, GFP_KERNEL | GFP_DMA);
407 if (devpriv->dma_buffer == NULL)
408 return -ENOMEM;
409
410 disable_dma(dma);
411 set_dma_mode(dma, DMA_MODE_READ);
412
413 devpriv->irq_dma_bits |= DMA_CHAN_BITS(dma);
414 }
415
416 dev->board_ptr = a2150_boards + a2150_probe(dev);
417 dev->board_name = thisboard->name;
418
419 if (alloc_subdevices(dev, 1) < 0)
420 return -ENOMEM;
421
422 /* analog input subdevice */
423 s = dev->subdevices + 0;
424 dev->read_subdev = s;
425 s->type = COMEDI_SUBD_AI;
426 s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_OTHER | SDF_CMD_READ;
427 s->n_chan = 4;
428 s->len_chanlist = 4;
429 s->maxdata = 0xffff;
430 s->range_table = &range_a2150;
431 s->do_cmd = a2150_ai_cmd;
432 s->do_cmdtest = a2150_ai_cmdtest;
433 s->insn_read = a2150_ai_rinsn;
434 s->cancel = a2150_cancel;
435
436 /* need to do this for software counting of completed conversions, to
437 * prevent hardware count from stopping aquisition */
438 outw(HW_COUNT_DISABLE, dev->iobase + I8253_MODE_REG);
439
440 /* set card's irq and dma levels */
441 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
442
443 /* reset and sync adc clock circuitry */
444 outw_p(DPD_BIT | APD_BIT, dev->iobase + CONFIG_REG);
445 outw_p(DPD_BIT, dev->iobase + CONFIG_REG);
446 /* initialize configuration register */
447 devpriv->config_bits = 0;
448 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
449 /* wait until offset calibration is done, then enable analog inputs */
450 for (i = 0; i < timeout; i++) {
451 if ((DCAL_BIT & inw(dev->iobase + STATUS_REG)) == 0)
452 break;
453 udelay(1000);
454 }
455 if (i == timeout) {
456 printk
457 (" timed out waiting for offset calibration to complete\n");
458 return -ETIME;
459 }
460 devpriv->config_bits |= ENABLE0_BIT | ENABLE1_BIT;
461 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
462
463 return 0;
464 };
465
466 static int a2150_detach(struct comedi_device *dev)
467 {
468 printk("comedi%d: %s: remove\n", dev->minor, driver_a2150.driver_name);
469
470 /* only free stuff if it has been allocated by _attach */
471 if (dev->iobase) {
472 /* put board in power-down mode */
473 outw(APD_BIT | DPD_BIT, dev->iobase + CONFIG_REG);
474 release_region(dev->iobase, A2150_SIZE);
475 }
476
477 if (dev->irq)
478 free_irq(dev->irq, dev);
479 if (devpriv) {
480 if (devpriv->dma)
481 free_dma(devpriv->dma);
482 if (devpriv->dma_buffer)
483 kfree(devpriv->dma_buffer);
484 }
485
486 return 0;
487 };
488
489 static int a2150_cancel(struct comedi_device *dev, struct comedi_subdevice *s)
490 {
491 /* disable dma on card */
492 devpriv->irq_dma_bits &= ~DMA_INTR_EN_BIT & ~DMA_EN_BIT;
493 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
494
495 /* disable computer's dma */
496 disable_dma(devpriv->dma);
497
498 /* clear fifo and reset triggering circuitry */
499 outw(0, dev->iobase + FIFO_RESET_REG);
500
501 return 0;
502 }
503
504 static int a2150_ai_cmdtest(struct comedi_device *dev,
505 struct comedi_subdevice *s, struct comedi_cmd *cmd)
506 {
507 int err = 0;
508 int tmp;
509 int startChan;
510 int i;
511
512 /* step 1: make sure trigger sources are trivially valid */
513
514 tmp = cmd->start_src;
515 cmd->start_src &= TRIG_NOW | TRIG_EXT;
516 if (!cmd->start_src || tmp != cmd->start_src)
517 err++;
518
519 tmp = cmd->scan_begin_src;
520 cmd->scan_begin_src &= TRIG_TIMER;
521 if (!cmd->scan_begin_src || tmp != cmd->scan_begin_src)
522 err++;
523
524 tmp = cmd->convert_src;
525 cmd->convert_src &= TRIG_NOW;
526 if (!cmd->convert_src || tmp != cmd->convert_src)
527 err++;
528
529 tmp = cmd->scan_end_src;
530 cmd->scan_end_src &= TRIG_COUNT;
531 if (!cmd->scan_end_src || tmp != cmd->scan_end_src)
532 err++;
533
534 tmp = cmd->stop_src;
535 cmd->stop_src &= TRIG_COUNT | TRIG_NONE;
536 if (!cmd->stop_src || tmp != cmd->stop_src)
537 err++;
538
539 if (err)
540 return 1;
541
542 /* step 2: make sure trigger sources are unique and mutually compatible */
543
544 if (cmd->start_src != TRIG_NOW && cmd->start_src != TRIG_EXT)
545 err++;
546 if (cmd->stop_src != TRIG_COUNT && cmd->stop_src != TRIG_NONE)
547 err++;
548
549 if (err)
550 return 2;
551
552 /* step 3: make sure arguments are trivially compatible */
553
554 if (cmd->start_arg != 0) {
555 cmd->start_arg = 0;
556 err++;
557 }
558 if (cmd->convert_src == TRIG_TIMER) {
559 if (cmd->convert_arg < thisboard->ai_speed) {
560 cmd->convert_arg = thisboard->ai_speed;
561 err++;
562 }
563 }
564 if (!cmd->chanlist_len) {
565 cmd->chanlist_len = 1;
566 err++;
567 }
568 if (cmd->scan_end_arg != cmd->chanlist_len) {
569 cmd->scan_end_arg = cmd->chanlist_len;
570 err++;
571 }
572 if (cmd->stop_src == TRIG_COUNT) {
573 if (!cmd->stop_arg) {
574 cmd->stop_arg = 1;
575 err++;
576 }
577 } else { /* TRIG_NONE */
578 if (cmd->stop_arg != 0) {
579 cmd->stop_arg = 0;
580 err++;
581 }
582 }
583
584 if (err)
585 return 3;
586
587 /* step 4: fix up any arguments */
588
589 if (cmd->scan_begin_src == TRIG_TIMER) {
590 tmp = cmd->scan_begin_arg;
591 a2150_get_timing(dev, &cmd->scan_begin_arg, cmd->flags);
592 if (tmp != cmd->scan_begin_arg)
593 err++;
594 }
595
596 if (err)
597 return 4;
598
599 /* check channel/gain list against card's limitations */
600 if (cmd->chanlist) {
601 startChan = CR_CHAN(cmd->chanlist[0]);
602 for (i = 1; i < cmd->chanlist_len; i++) {
603 if (CR_CHAN(cmd->chanlist[i]) != (startChan + i)) {
604 comedi_error(dev,
605 "entries in chanlist must be consecutive channels, counting upwards\n");
606 err++;
607 }
608 }
609 if (cmd->chanlist_len == 2 && CR_CHAN(cmd->chanlist[0]) == 1) {
610 comedi_error(dev,
611 "length 2 chanlist must be channels 0,1 or channels 2,3");
612 err++;
613 }
614 if (cmd->chanlist_len == 3) {
615 comedi_error(dev,
616 "chanlist must have 1,2 or 4 channels");
617 err++;
618 }
619 if (CR_AREF(cmd->chanlist[0]) != CR_AREF(cmd->chanlist[1]) ||
620 CR_AREF(cmd->chanlist[2]) != CR_AREF(cmd->chanlist[3])) {
621 comedi_error(dev,
622 "channels 0/1 and 2/3 must have the same analog reference");
623 err++;
624 }
625 }
626
627 if (err)
628 return 5;
629
630 return 0;
631 }
632
633 static int a2150_ai_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
634 {
635 struct comedi_async *async = s->async;
636 struct comedi_cmd *cmd = &async->cmd;
637 unsigned long lock_flags;
638 unsigned int old_config_bits = devpriv->config_bits;
639 unsigned int trigger_bits;
640
641 if (!dev->irq || !devpriv->dma) {
642 comedi_error(dev,
643 " irq and dma required, cannot do hardware conversions");
644 return -1;
645 }
646 if (cmd->flags & TRIG_RT) {
647 comedi_error(dev,
648 " dma incompatible with hard real-time interrupt (TRIG_RT), aborting");
649 return -1;
650 }
651 /* clear fifo and reset triggering circuitry */
652 outw(0, dev->iobase + FIFO_RESET_REG);
653
654 /* setup chanlist */
655 if (a2150_set_chanlist(dev, CR_CHAN(cmd->chanlist[0]),
656 cmd->chanlist_len) < 0)
657 return -1;
658
659 /* setup ac/dc coupling */
660 if (CR_AREF(cmd->chanlist[0]) == AREF_OTHER)
661 devpriv->config_bits |= AC0_BIT;
662 else
663 devpriv->config_bits &= ~AC0_BIT;
664 if (CR_AREF(cmd->chanlist[2]) == AREF_OTHER)
665 devpriv->config_bits |= AC1_BIT;
666 else
667 devpriv->config_bits &= ~AC1_BIT;
668
669 /* setup timing */
670 a2150_get_timing(dev, &cmd->scan_begin_arg, cmd->flags);
671
672 /* send timing, channel, config bits */
673 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
674
675 /* initialize number of samples remaining */
676 devpriv->count = cmd->stop_arg * cmd->chanlist_len;
677
678 /* enable computer's dma */
679 lock_flags = claim_dma_lock();
680 disable_dma(devpriv->dma);
681 /* clear flip-flop to make sure 2-byte registers for
682 * count and address get set correctly */
683 clear_dma_ff(devpriv->dma);
684 set_dma_addr(devpriv->dma, virt_to_bus(devpriv->dma_buffer));
685 /* set size of transfer to fill in 1/3 second */
686 #define ONE_THIRD_SECOND 333333333
687 devpriv->dma_transfer_size =
688 sizeof(devpriv->dma_buffer[0]) * cmd->chanlist_len *
689 ONE_THIRD_SECOND / cmd->scan_begin_arg;
690 if (devpriv->dma_transfer_size > A2150_DMA_BUFFER_SIZE)
691 devpriv->dma_transfer_size = A2150_DMA_BUFFER_SIZE;
692 if (devpriv->dma_transfer_size < sizeof(devpriv->dma_buffer[0]))
693 devpriv->dma_transfer_size = sizeof(devpriv->dma_buffer[0]);
694 devpriv->dma_transfer_size -=
695 devpriv->dma_transfer_size % sizeof(devpriv->dma_buffer[0]);
696 set_dma_count(devpriv->dma, devpriv->dma_transfer_size);
697 enable_dma(devpriv->dma);
698 release_dma_lock(lock_flags);
699
700 /* clear dma interrupt before enabling it, to try and get rid of that
701 * one spurious interrupt that has been happening */
702 outw(0x00, dev->iobase + DMA_TC_CLEAR_REG);
703
704 /* enable dma on card */
705 devpriv->irq_dma_bits |= DMA_INTR_EN_BIT | DMA_EN_BIT;
706 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
707
708 /* may need to wait 72 sampling periods if timing was changed */
709 i8254_load(dev->iobase + I8253_BASE_REG, 0, 2, 72, 0);
710
711 /* setup start triggering */
712 trigger_bits = 0;
713 /* decide if we need to wait 72 periods for valid data */
714 if (cmd->start_src == TRIG_NOW &&
715 (old_config_bits & CLOCK_MASK) !=
716 (devpriv->config_bits & CLOCK_MASK)) {
717 /* set trigger source to delay trigger */
718 trigger_bits |= DELAY_TRIGGER_BITS;
719 } else {
720 /* otherwise no delay */
721 trigger_bits |= POST_TRIGGER_BITS;
722 }
723 /* enable external hardware trigger */
724 if (cmd->start_src == TRIG_EXT) {
725 trigger_bits |= HW_TRIG_EN;
726 } else if (cmd->start_src == TRIG_OTHER) {
727 /* XXX add support for level/slope start trigger using TRIG_OTHER */
728 comedi_error(dev, "you shouldn't see this?");
729 }
730 /* send trigger config bits */
731 outw(trigger_bits, dev->iobase + TRIGGER_REG);
732
733 /* start aquisition for soft trigger */
734 if (cmd->start_src == TRIG_NOW) {
735 outw(0, dev->iobase + FIFO_START_REG);
736 }
737 #ifdef A2150_DEBUG
738 ni_dump_regs(dev);
739 #endif
740
741 return 0;
742 }
743
744 static int a2150_ai_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
745 struct comedi_insn *insn, unsigned int *data)
746 {
747 unsigned int i, n;
748 static const int timeout = 100000;
749 static const int filter_delay = 36;
750
751 /* clear fifo and reset triggering circuitry */
752 outw(0, dev->iobase + FIFO_RESET_REG);
753
754 /* setup chanlist */
755 if (a2150_set_chanlist(dev, CR_CHAN(insn->chanspec), 1) < 0)
756 return -1;
757
758 /* set dc coupling */
759 devpriv->config_bits &= ~AC0_BIT;
760 devpriv->config_bits &= ~AC1_BIT;
761
762 /* send timing, channel, config bits */
763 outw(devpriv->config_bits, dev->iobase + CONFIG_REG);
764
765 /* disable dma on card */
766 devpriv->irq_dma_bits &= ~DMA_INTR_EN_BIT & ~DMA_EN_BIT;
767 outw(devpriv->irq_dma_bits, dev->iobase + IRQ_DMA_CNTRL_REG);
768
769 /* setup start triggering */
770 outw(0, dev->iobase + TRIGGER_REG);
771
772 /* start aquisition for soft trigger */
773 outw(0, dev->iobase + FIFO_START_REG);
774
775 /* there is a 35.6 sample delay for data to get through the antialias filter */
776 for (n = 0; n < filter_delay; n++) {
777 for (i = 0; i < timeout; i++) {
778 if (inw(dev->iobase + STATUS_REG) & FNE_BIT)
779 break;
780 udelay(1);
781 }
782 if (i == timeout) {
783 comedi_error(dev, "timeout");
784 return -ETIME;
785 }
786 inw(dev->iobase + FIFO_DATA_REG);
787 }
788
789 /* read data */
790 for (n = 0; n < insn->n; n++) {
791 for (i = 0; i < timeout; i++) {
792 if (inw(dev->iobase + STATUS_REG) & FNE_BIT)
793 break;
794 udelay(1);
795 }
796 if (i == timeout) {
797 comedi_error(dev, "timeout");
798 return -ETIME;
799 }
800 #ifdef A2150_DEBUG
801 ni_dump_regs(dev);
802 #endif
803 data[n] = inw(dev->iobase + FIFO_DATA_REG);
804 #ifdef A2150_DEBUG
805 printk(" data is %i\n", data[n]);
806 #endif
807 data[n] ^= 0x8000;
808 }
809
810 /* clear fifo and reset triggering circuitry */
811 outw(0, dev->iobase + FIFO_RESET_REG);
812
813 return n;
814 }
815
816 /* sets bits in devpriv->clock_bits to nearest approximation of requested period,
817 * adjusts requested period to actual timing. */
818 static int a2150_get_timing(struct comedi_device *dev, unsigned int *period,
819 int flags)
820 {
821 int lub, glb, temp;
822 int lub_divisor_shift, lub_index, glb_divisor_shift, glb_index;
823 int i, j;
824
825 /* initialize greatest lower and least upper bounds */
826 lub_divisor_shift = 3;
827 lub_index = 0;
828 lub = thisboard->clock[lub_index] * (1 << lub_divisor_shift);
829 glb_divisor_shift = 0;
830 glb_index = thisboard->num_clocks - 1;
831 glb = thisboard->clock[glb_index] * (1 << glb_divisor_shift);
832
833 /* make sure period is in available range */
834 if (*period < glb)
835 *period = glb;
836 if (*period > lub)
837 *period = lub;
838
839 /* we can multiply period by 1, 2, 4, or 8, using (1 << i) */
840 for (i = 0; i < 4; i++) {
841 /* there are a maximum of 4 master clocks */
842 for (j = 0; j < thisboard->num_clocks; j++) {
843 /* temp is the period in nanosec we are evaluating */
844 temp = thisboard->clock[j] * (1 << i);
845 /* if it is the best match yet */
846 if (temp < lub && temp >= *period) {
847 lub_divisor_shift = i;
848 lub_index = j;
849 lub = temp;
850 }
851 if (temp > glb && temp <= *period) {
852 glb_divisor_shift = i;
853 glb_index = j;
854 glb = temp;
855 }
856 }
857 }
858 flags &= TRIG_ROUND_MASK;
859 switch (flags) {
860 case TRIG_ROUND_NEAREST:
861 default:
862 /* if least upper bound is better approximation */
863 if (lub - *period < *period - glb) {
864 *period = lub;
865 } else {
866 *period = glb;
867 }
868 break;
869 case TRIG_ROUND_UP:
870 *period = lub;
871 break;
872 case TRIG_ROUND_DOWN:
873 *period = glb;
874 break;
875 }
876
877 /* set clock bits for config register appropriately */
878 devpriv->config_bits &= ~CLOCK_MASK;
879 if (*period == lub) {
880 devpriv->config_bits |=
881 CLOCK_SELECT_BITS(lub_index) |
882 CLOCK_DIVISOR_BITS(lub_divisor_shift);
883 } else {
884 devpriv->config_bits |=
885 CLOCK_SELECT_BITS(glb_index) |
886 CLOCK_DIVISOR_BITS(glb_divisor_shift);
887 }
888
889 return 0;
890 }
891
892 static int a2150_set_chanlist(struct comedi_device *dev,
893 unsigned int start_channel,
894 unsigned int num_channels)
895 {
896 if (start_channel + num_channels > 4)
897 return -1;
898
899 devpriv->config_bits &= ~CHANNEL_MASK;
900
901 switch (num_channels) {
902 case 1:
903 devpriv->config_bits |= CHANNEL_BITS(0x4 | start_channel);
904 break;
905 case 2:
906 if (start_channel == 0) {
907 devpriv->config_bits |= CHANNEL_BITS(0x2);
908 } else if (start_channel == 2) {
909 devpriv->config_bits |= CHANNEL_BITS(0x3);
910 } else {
911 return -1;
912 }
913 break;
914 case 4:
915 devpriv->config_bits |= CHANNEL_BITS(0x1);
916 break;
917 default:
918 return -1;
919 break;
920 }
921
922 return 0;
923 }
924
925 MODULE_AUTHOR("Comedi http://www.comedi.org");
926 MODULE_DESCRIPTION("Comedi low-level driver");
927 MODULE_LICENSE("GPL");