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48#include <linux/module.h>
49#include "../comedidev.h"
50
51#include <asm/div64.h>
52
53#include "comedi_fc.h"
54#include <linux/timer.h>
55
56#define N_CHANS 8
57
58
59struct waveform_private {
60 struct timer_list timer;
61 struct timeval last;
62 unsigned int uvolt_amplitude;
63 unsigned long usec_period;
64 unsigned long usec_current;
65 unsigned long usec_remainder;
66 unsigned long ai_count;
67 unsigned int scan_period;
68 unsigned int convert_period;
69 unsigned int ao_loopbacks[N_CHANS];
70};
71
72
73static const int nano_per_micro = 1000;
74
75
76static const struct comedi_lrange waveform_ai_ranges = {
77 2,
78 {
79 BIP_RANGE(10),
80 BIP_RANGE(5),
81 }
82};
83
84static unsigned short fake_sawtooth(struct comedi_device *dev,
85 unsigned int range_index,
86 unsigned long current_time)
87{
88 struct waveform_private *devpriv = dev->private;
89 struct comedi_subdevice *s = dev->read_subdev;
90 unsigned int offset = s->maxdata / 2;
91 u64 value;
92 const struct comedi_krange *krange =
93 &s->range_table->range[range_index];
94 u64 binary_amplitude;
95
96 binary_amplitude = s->maxdata;
97 binary_amplitude *= devpriv->uvolt_amplitude;
98 do_div(binary_amplitude, krange->max - krange->min);
99
100 current_time %= devpriv->usec_period;
101 value = current_time;
102 value *= binary_amplitude * 2;
103 do_div(value, devpriv->usec_period);
104 value -= binary_amplitude;
105
106 return offset + value;
107}
108
109static unsigned short fake_squarewave(struct comedi_device *dev,
110 unsigned int range_index,
111 unsigned long current_time)
112{
113 struct waveform_private *devpriv = dev->private;
114 struct comedi_subdevice *s = dev->read_subdev;
115 unsigned int offset = s->maxdata / 2;
116 u64 value;
117 const struct comedi_krange *krange =
118 &s->range_table->range[range_index];
119 current_time %= devpriv->usec_period;
120
121 value = s->maxdata;
122 value *= devpriv->uvolt_amplitude;
123 do_div(value, krange->max - krange->min);
124
125 if (current_time < devpriv->usec_period / 2)
126 value *= -1;
127
128 return offset + value;
129}
130
131static unsigned short fake_flatline(struct comedi_device *dev,
132 unsigned int range_index,
133 unsigned long current_time)
134{
135 return dev->read_subdev->maxdata / 2;
136}
137
138
139static unsigned short fake_waveform(struct comedi_device *dev,
140 unsigned int channel, unsigned int range,
141 unsigned long current_time)
142{
143 enum {
144 SAWTOOTH_CHAN,
145 SQUARE_CHAN,
146 };
147 switch (channel) {
148 case SAWTOOTH_CHAN:
149 return fake_sawtooth(dev, range, current_time);
150 break;
151 case SQUARE_CHAN:
152 return fake_squarewave(dev, range, current_time);
153 break;
154 default:
155 break;
156 }
157
158 return fake_flatline(dev, range, current_time);
159}
160
161
162
163
164
165
166static void waveform_ai_interrupt(unsigned long arg)
167{
168 struct comedi_device *dev = (struct comedi_device *)arg;
169 struct waveform_private *devpriv = dev->private;
170 struct comedi_async *async = dev->read_subdev->async;
171 struct comedi_cmd *cmd = &async->cmd;
172 unsigned int i, j;
173
174 unsigned long elapsed_time;
175 unsigned int num_scans;
176 struct timeval now;
177 bool stopping = false;
178
179 do_gettimeofday(&now);
180
181 elapsed_time =
182 1000000 * (now.tv_sec - devpriv->last.tv_sec) + now.tv_usec -
183 devpriv->last.tv_usec;
184 devpriv->last = now;
185 num_scans =
186 (devpriv->usec_remainder + elapsed_time) / devpriv->scan_period;
187 devpriv->usec_remainder =
188 (devpriv->usec_remainder + elapsed_time) % devpriv->scan_period;
189 async->events = 0;
190
191 if (cmd->stop_src == TRIG_COUNT) {
192 unsigned int remaining = cmd->stop_arg - devpriv->ai_count;
193 if (num_scans >= remaining) {
194
195 num_scans = remaining;
196 stopping = true;
197 }
198 }
199
200 for (i = 0; i < num_scans; i++) {
201 for (j = 0; j < cmd->chanlist_len; j++) {
202 unsigned short sample;
203 sample = fake_waveform(dev, CR_CHAN(cmd->chanlist[j]),
204 CR_RANGE(cmd->chanlist[j]),
205 devpriv->usec_current +
206 i * devpriv->scan_period +
207 j * devpriv->convert_period);
208 cfc_write_to_buffer(dev->read_subdev, sample);
209 }
210 }
211
212 devpriv->ai_count += i;
213 devpriv->usec_current += elapsed_time;
214 devpriv->usec_current %= devpriv->usec_period;
215
216 if (stopping)
217 async->events |= COMEDI_CB_EOA;
218 else
219 mod_timer(&devpriv->timer, jiffies + 1);
220
221 comedi_event(dev, dev->read_subdev);
222}
223
224static int waveform_ai_cmdtest(struct comedi_device *dev,
225 struct comedi_subdevice *s,
226 struct comedi_cmd *cmd)
227{
228 int err = 0;
229 int tmp;
230
231
232
233 err |= cfc_check_trigger_src(&cmd->start_src, TRIG_NOW);
234 err |= cfc_check_trigger_src(&cmd->scan_begin_src, TRIG_TIMER);
235 err |= cfc_check_trigger_src(&cmd->convert_src, TRIG_NOW | TRIG_TIMER);
236 err |= cfc_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
237 err |= cfc_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
238
239 if (err)
240 return 1;
241
242
243
244 err |= cfc_check_trigger_is_unique(cmd->convert_src);
245 err |= cfc_check_trigger_is_unique(cmd->stop_src);
246
247
248
249 if (err)
250 return 2;
251
252
253
254 err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
255
256 if (cmd->convert_src == TRIG_NOW)
257 err |= cfc_check_trigger_arg_is(&cmd->convert_arg, 0);
258
259 if (cmd->scan_begin_src == TRIG_TIMER) {
260 err |= cfc_check_trigger_arg_min(&cmd->scan_begin_arg,
261 nano_per_micro);
262 if (cmd->convert_src == TRIG_TIMER)
263 err |= cfc_check_trigger_arg_min(&cmd->scan_begin_arg,
264 cmd->convert_arg * cmd->chanlist_len);
265 }
266
267 err |= cfc_check_trigger_arg_min(&cmd->chanlist_len, 1);
268 err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len);
269
270 if (cmd->stop_src == TRIG_COUNT)
271 err |= cfc_check_trigger_arg_min(&cmd->stop_arg, 1);
272 else
273 err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
274
275 if (err)
276 return 3;
277
278
279
280 if (cmd->scan_begin_src == TRIG_TIMER) {
281 tmp = cmd->scan_begin_arg;
282
283 cmd->scan_begin_arg =
284 nano_per_micro * ((tmp +
285 (nano_per_micro / 2)) / nano_per_micro);
286 if (tmp != cmd->scan_begin_arg)
287 err++;
288 }
289 if (cmd->convert_src == TRIG_TIMER) {
290 tmp = cmd->convert_arg;
291
292 cmd->convert_arg =
293 nano_per_micro * ((tmp +
294 (nano_per_micro / 2)) / nano_per_micro);
295 if (tmp != cmd->convert_arg)
296 err++;
297 }
298
299 if (err)
300 return 4;
301
302 return 0;
303}
304
305static int waveform_ai_cmd(struct comedi_device *dev,
306 struct comedi_subdevice *s)
307{
308 struct waveform_private *devpriv = dev->private;
309 struct comedi_cmd *cmd = &s->async->cmd;
310
311 if (cmd->flags & TRIG_RT) {
312 comedi_error(dev,
313 "commands at RT priority not supported in this driver");
314 return -1;
315 }
316
317 devpriv->ai_count = 0;
318 devpriv->scan_period = cmd->scan_begin_arg / nano_per_micro;
319
320 if (cmd->convert_src == TRIG_NOW)
321 devpriv->convert_period = 0;
322 else if (cmd->convert_src == TRIG_TIMER)
323 devpriv->convert_period = cmd->convert_arg / nano_per_micro;
324 else {
325 comedi_error(dev, "bug setting conversion period");
326 return -1;
327 }
328
329 do_gettimeofday(&devpriv->last);
330 devpriv->usec_current = devpriv->last.tv_usec % devpriv->usec_period;
331 devpriv->usec_remainder = 0;
332
333 devpriv->timer.expires = jiffies + 1;
334 add_timer(&devpriv->timer);
335 return 0;
336}
337
338static int waveform_ai_cancel(struct comedi_device *dev,
339 struct comedi_subdevice *s)
340{
341 struct waveform_private *devpriv = dev->private;
342
343 del_timer_sync(&devpriv->timer);
344 return 0;
345}
346
347static int waveform_ai_insn_read(struct comedi_device *dev,
348 struct comedi_subdevice *s,
349 struct comedi_insn *insn, unsigned int *data)
350{
351 struct waveform_private *devpriv = dev->private;
352 int i, chan = CR_CHAN(insn->chanspec);
353
354 for (i = 0; i < insn->n; i++)
355 data[i] = devpriv->ao_loopbacks[chan];
356
357 return insn->n;
358}
359
360static int waveform_ao_insn_write(struct comedi_device *dev,
361 struct comedi_subdevice *s,
362 struct comedi_insn *insn, unsigned int *data)
363{
364 struct waveform_private *devpriv = dev->private;
365 int i, chan = CR_CHAN(insn->chanspec);
366
367 for (i = 0; i < insn->n; i++)
368 devpriv->ao_loopbacks[chan] = data[i];
369
370 return insn->n;
371}
372
373static int waveform_attach(struct comedi_device *dev,
374 struct comedi_devconfig *it)
375{
376 struct waveform_private *devpriv;
377 struct comedi_subdevice *s;
378 int amplitude = it->options[0];
379 int period = it->options[1];
380 int i;
381 int ret;
382
383 devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
384 if (!devpriv)
385 return -ENOMEM;
386
387
388 if (amplitude <= 0)
389 amplitude = 1000000;
390 if (period <= 0)
391 period = 100000;
392
393 devpriv->uvolt_amplitude = amplitude;
394 devpriv->usec_period = period;
395
396 ret = comedi_alloc_subdevices(dev, 2);
397 if (ret)
398 return ret;
399
400 s = &dev->subdevices[0];
401 dev->read_subdev = s;
402
403 s->type = COMEDI_SUBD_AI;
404 s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_CMD_READ;
405 s->n_chan = N_CHANS;
406 s->maxdata = 0xffff;
407 s->range_table = &waveform_ai_ranges;
408 s->len_chanlist = s->n_chan * 2;
409 s->insn_read = waveform_ai_insn_read;
410 s->do_cmd = waveform_ai_cmd;
411 s->do_cmdtest = waveform_ai_cmdtest;
412 s->cancel = waveform_ai_cancel;
413
414 s = &dev->subdevices[1];
415 dev->write_subdev = s;
416
417 s->type = COMEDI_SUBD_AO;
418 s->subdev_flags = SDF_WRITEABLE | SDF_GROUND;
419 s->n_chan = N_CHANS;
420 s->maxdata = 0xffff;
421 s->range_table = &waveform_ai_ranges;
422 s->len_chanlist = s->n_chan * 2;
423 s->insn_write = waveform_ao_insn_write;
424 s->do_cmd = NULL;
425 s->do_cmdtest = NULL;
426 s->cancel = NULL;
427
428
429 for (i = 0; i < s->n_chan; i++)
430 devpriv->ao_loopbacks[i] = s->maxdata / 2;
431
432 init_timer(&(devpriv->timer));
433 devpriv->timer.function = waveform_ai_interrupt;
434 devpriv->timer.data = (unsigned long)dev;
435
436 dev_info(dev->class_dev,
437 "%s: %i microvolt, %li microsecond waveform attached\n",
438 dev->board_name,
439 devpriv->uvolt_amplitude, devpriv->usec_period);
440
441 return 0;
442}
443
444static void waveform_detach(struct comedi_device *dev)
445{
446 struct waveform_private *devpriv = dev->private;
447
448 if (devpriv)
449 waveform_ai_cancel(dev, dev->read_subdev);
450}
451
452static struct comedi_driver waveform_driver = {
453 .driver_name = "comedi_test",
454 .module = THIS_MODULE,
455 .attach = waveform_attach,
456 .detach = waveform_detach,
457};
458module_comedi_driver(waveform_driver);
459
460MODULE_AUTHOR("Comedi http://www.comedi.org");
461MODULE_DESCRIPTION("Comedi low-level driver");
462MODULE_LICENSE("GPL");
463