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53#include "../comedidev.h"
54
55#include <asm/div64.h>
56
57#include "comedi_fc.h"
58#include <linux/timer.h>
59
60#define N_CHANS 8
61
62
63struct waveform_private {
64 struct timer_list timer;
65 struct timeval last;
66 unsigned int uvolt_amplitude;
67 unsigned long usec_period;
68 unsigned long usec_current;
69 unsigned long usec_remainder;
70 unsigned long ai_count;
71 unsigned int scan_period;
72 unsigned int convert_period;
73 unsigned int ao_loopbacks[N_CHANS];
74};
75
76
77static const int nano_per_micro = 1000;
78
79
80static const struct comedi_lrange waveform_ai_ranges = {
81 2,
82 {
83 BIP_RANGE(10),
84 BIP_RANGE(5),
85 }
86};
87
88static unsigned short fake_sawtooth(struct comedi_device *dev,
89 unsigned int range_index,
90 unsigned long current_time)
91{
92 struct waveform_private *devpriv = dev->private;
93 struct comedi_subdevice *s = dev->read_subdev;
94 unsigned int offset = s->maxdata / 2;
95 u64 value;
96 const struct comedi_krange *krange =
97 &s->range_table->range[range_index];
98 u64 binary_amplitude;
99
100 binary_amplitude = s->maxdata;
101 binary_amplitude *= devpriv->uvolt_amplitude;
102 do_div(binary_amplitude, krange->max - krange->min);
103
104 current_time %= devpriv->usec_period;
105 value = current_time;
106 value *= binary_amplitude * 2;
107 do_div(value, devpriv->usec_period);
108 value -= binary_amplitude;
109
110 return offset + value;
111}
112
113static unsigned short fake_squarewave(struct comedi_device *dev,
114 unsigned int range_index,
115 unsigned long current_time)
116{
117 struct waveform_private *devpriv = dev->private;
118 struct comedi_subdevice *s = dev->read_subdev;
119 unsigned int offset = s->maxdata / 2;
120 u64 value;
121 const struct comedi_krange *krange =
122 &s->range_table->range[range_index];
123 current_time %= devpriv->usec_period;
124
125 value = s->maxdata;
126 value *= devpriv->uvolt_amplitude;
127 do_div(value, krange->max - krange->min);
128
129 if (current_time < devpriv->usec_period / 2)
130 value *= -1;
131
132 return offset + value;
133}
134
135static unsigned short fake_flatline(struct comedi_device *dev,
136 unsigned int range_index,
137 unsigned long current_time)
138{
139 return dev->read_subdev->maxdata / 2;
140}
141
142
143static unsigned short fake_waveform(struct comedi_device *dev,
144 unsigned int channel, unsigned int range,
145 unsigned long current_time)
146{
147 enum {
148 SAWTOOTH_CHAN,
149 SQUARE_CHAN,
150 };
151 switch (channel) {
152 case SAWTOOTH_CHAN:
153 return fake_sawtooth(dev, range, current_time);
154 break;
155 case SQUARE_CHAN:
156 return fake_squarewave(dev, range, current_time);
157 break;
158 default:
159 break;
160 }
161
162 return fake_flatline(dev, range, current_time);
163}
164
165
166
167
168
169
170static void waveform_ai_interrupt(unsigned long arg)
171{
172 struct comedi_device *dev = (struct comedi_device *)arg;
173 struct waveform_private *devpriv = dev->private;
174 struct comedi_async *async = dev->read_subdev->async;
175 struct comedi_cmd *cmd = &async->cmd;
176 unsigned int i, j;
177
178 unsigned long elapsed_time;
179 unsigned int num_scans;
180 struct timeval now;
181 bool stopping = false;
182
183 do_gettimeofday(&now);
184
185 elapsed_time =
186 1000000 * (now.tv_sec - devpriv->last.tv_sec) + now.tv_usec -
187 devpriv->last.tv_usec;
188 devpriv->last = now;
189 num_scans =
190 (devpriv->usec_remainder + elapsed_time) / devpriv->scan_period;
191 devpriv->usec_remainder =
192 (devpriv->usec_remainder + elapsed_time) % devpriv->scan_period;
193 async->events = 0;
194
195 if (cmd->stop_src == TRIG_COUNT) {
196 unsigned int remaining = cmd->stop_arg - devpriv->ai_count;
197 if (num_scans >= remaining) {
198
199 num_scans = remaining;
200 stopping = true;
201 }
202 }
203
204 for (i = 0; i < num_scans; i++) {
205 for (j = 0; j < cmd->chanlist_len; j++) {
206 unsigned short sample;
207 sample = fake_waveform(dev, CR_CHAN(cmd->chanlist[j]),
208 CR_RANGE(cmd->chanlist[j]),
209 devpriv->usec_current +
210 i * devpriv->scan_period +
211 j * devpriv->convert_period);
212 cfc_write_to_buffer(dev->read_subdev, sample);
213 }
214 }
215
216 devpriv->ai_count += i;
217 devpriv->usec_current += elapsed_time;
218 devpriv->usec_current %= devpriv->usec_period;
219
220 if (stopping)
221 async->events |= COMEDI_CB_EOA;
222 else
223 mod_timer(&devpriv->timer, jiffies + 1);
224
225 comedi_event(dev, dev->read_subdev);
226}
227
228static int waveform_ai_cmdtest(struct comedi_device *dev,
229 struct comedi_subdevice *s,
230 struct comedi_cmd *cmd)
231{
232 int err = 0;
233 int tmp;
234
235
236
237 err |= cfc_check_trigger_src(&cmd->start_src, TRIG_NOW);
238 err |= cfc_check_trigger_src(&cmd->scan_begin_src, TRIG_TIMER);
239 err |= cfc_check_trigger_src(&cmd->convert_src, TRIG_NOW | TRIG_TIMER);
240 err |= cfc_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
241 err |= cfc_check_trigger_src(&cmd->stop_src, TRIG_COUNT | TRIG_NONE);
242
243 if (err)
244 return 1;
245
246
247
248 err |= cfc_check_trigger_is_unique(cmd->convert_src);
249 err |= cfc_check_trigger_is_unique(cmd->stop_src);
250
251
252
253 if (err)
254 return 2;
255
256
257
258 err |= cfc_check_trigger_arg_is(&cmd->start_arg, 0);
259
260 if (cmd->convert_src == TRIG_NOW)
261 err |= cfc_check_trigger_arg_is(&cmd->convert_arg, 0);
262
263 if (cmd->scan_begin_src == TRIG_TIMER) {
264 err |= cfc_check_trigger_arg_min(&cmd->scan_begin_arg,
265 nano_per_micro);
266 if (cmd->convert_src == TRIG_TIMER)
267 err |= cfc_check_trigger_arg_min(&cmd->scan_begin_arg,
268 cmd->convert_arg * cmd->chanlist_len);
269 }
270
271 err |= cfc_check_trigger_arg_min(&cmd->chanlist_len, 1);
272 err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len);
273
274 if (cmd->stop_src == TRIG_COUNT)
275 err |= cfc_check_trigger_arg_min(&cmd->stop_arg, 1);
276 else
277 err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0);
278
279 if (err)
280 return 3;
281
282
283
284 if (cmd->scan_begin_src == TRIG_TIMER) {
285 tmp = cmd->scan_begin_arg;
286
287 cmd->scan_begin_arg =
288 nano_per_micro * ((tmp +
289 (nano_per_micro / 2)) / nano_per_micro);
290 if (tmp != cmd->scan_begin_arg)
291 err++;
292 }
293 if (cmd->convert_src == TRIG_TIMER) {
294 tmp = cmd->convert_arg;
295
296 cmd->convert_arg =
297 nano_per_micro * ((tmp +
298 (nano_per_micro / 2)) / nano_per_micro);
299 if (tmp != cmd->convert_arg)
300 err++;
301 }
302
303 if (err)
304 return 4;
305
306 return 0;
307}
308
309static int waveform_ai_cmd(struct comedi_device *dev,
310 struct comedi_subdevice *s)
311{
312 struct waveform_private *devpriv = dev->private;
313 struct comedi_cmd *cmd = &s->async->cmd;
314
315 if (cmd->flags & TRIG_RT) {
316 comedi_error(dev,
317 "commands at RT priority not supported in this driver");
318 return -1;
319 }
320
321 devpriv->ai_count = 0;
322 devpriv->scan_period = cmd->scan_begin_arg / nano_per_micro;
323
324 if (cmd->convert_src == TRIG_NOW)
325 devpriv->convert_period = 0;
326 else if (cmd->convert_src == TRIG_TIMER)
327 devpriv->convert_period = cmd->convert_arg / nano_per_micro;
328 else {
329 comedi_error(dev, "bug setting conversion period");
330 return -1;
331 }
332
333 do_gettimeofday(&devpriv->last);
334 devpriv->usec_current = devpriv->last.tv_usec % devpriv->usec_period;
335 devpriv->usec_remainder = 0;
336
337 devpriv->timer.expires = jiffies + 1;
338 add_timer(&devpriv->timer);
339 return 0;
340}
341
342static int waveform_ai_cancel(struct comedi_device *dev,
343 struct comedi_subdevice *s)
344{
345 struct waveform_private *devpriv = dev->private;
346
347 del_timer_sync(&devpriv->timer);
348 return 0;
349}
350
351static int waveform_ai_insn_read(struct comedi_device *dev,
352 struct comedi_subdevice *s,
353 struct comedi_insn *insn, unsigned int *data)
354{
355 struct waveform_private *devpriv = dev->private;
356 int i, chan = CR_CHAN(insn->chanspec);
357
358 for (i = 0; i < insn->n; i++)
359 data[i] = devpriv->ao_loopbacks[chan];
360
361 return insn->n;
362}
363
364static int waveform_ao_insn_write(struct comedi_device *dev,
365 struct comedi_subdevice *s,
366 struct comedi_insn *insn, unsigned int *data)
367{
368 struct waveform_private *devpriv = dev->private;
369 int i, chan = CR_CHAN(insn->chanspec);
370
371 for (i = 0; i < insn->n; i++)
372 devpriv->ao_loopbacks[chan] = data[i];
373
374 return insn->n;
375}
376
377static int waveform_attach(struct comedi_device *dev,
378 struct comedi_devconfig *it)
379{
380 struct waveform_private *devpriv;
381 struct comedi_subdevice *s;
382 int amplitude = it->options[0];
383 int period = it->options[1];
384 int i;
385 int ret;
386
387 devpriv = kzalloc(sizeof(*devpriv), GFP_KERNEL);
388 if (!devpriv)
389 return -ENOMEM;
390 dev->private = devpriv;
391
392
393 if (amplitude <= 0)
394 amplitude = 1000000;
395 if (period <= 0)
396 period = 100000;
397
398 devpriv->uvolt_amplitude = amplitude;
399 devpriv->usec_period = period;
400
401 ret = comedi_alloc_subdevices(dev, 2);
402 if (ret)
403 return ret;
404
405 s = &dev->subdevices[0];
406 dev->read_subdev = s;
407
408 s->type = COMEDI_SUBD_AI;
409 s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_CMD_READ;
410 s->n_chan = N_CHANS;
411 s->maxdata = 0xffff;
412 s->range_table = &waveform_ai_ranges;
413 s->len_chanlist = s->n_chan * 2;
414 s->insn_read = waveform_ai_insn_read;
415 s->do_cmd = waveform_ai_cmd;
416 s->do_cmdtest = waveform_ai_cmdtest;
417 s->cancel = waveform_ai_cancel;
418
419 s = &dev->subdevices[1];
420 dev->write_subdev = s;
421
422 s->type = COMEDI_SUBD_AO;
423 s->subdev_flags = SDF_WRITEABLE | SDF_GROUND;
424 s->n_chan = N_CHANS;
425 s->maxdata = 0xffff;
426 s->range_table = &waveform_ai_ranges;
427 s->len_chanlist = s->n_chan * 2;
428 s->insn_write = waveform_ao_insn_write;
429 s->do_cmd = NULL;
430 s->do_cmdtest = NULL;
431 s->cancel = NULL;
432
433
434 for (i = 0; i < s->n_chan; i++)
435 devpriv->ao_loopbacks[i] = s->maxdata / 2;
436
437 init_timer(&(devpriv->timer));
438 devpriv->timer.function = waveform_ai_interrupt;
439 devpriv->timer.data = (unsigned long)dev;
440
441 dev_info(dev->class_dev,
442 "%s: %i microvolt, %li microsecond waveform attached\n",
443 dev->board_name,
444 devpriv->uvolt_amplitude, devpriv->usec_period);
445
446 return 0;
447}
448
449static void waveform_detach(struct comedi_device *dev)
450{
451 struct waveform_private *devpriv = dev->private;
452
453 if (devpriv)
454 waveform_ai_cancel(dev, dev->read_subdev);
455}
456
457static struct comedi_driver waveform_driver = {
458 .driver_name = "comedi_test",
459 .module = THIS_MODULE,
460 .attach = waveform_attach,
461 .detach = waveform_detach,
462};
463module_comedi_driver(waveform_driver);
464
465MODULE_AUTHOR("Comedi http://www.comedi.org");
466MODULE_DESCRIPTION("Comedi low-level driver");
467MODULE_LICENSE("GPL");
468